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Surgical Management of Varicose Veins of the Lower Limbs: Retrospective Study of 280 Patients
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作者 Papa Amath Diagne Abdoul Aziz Thiaw +14 位作者 Momar Sokhna Diop Ndeye Fatou Sow Abdoul Ahad Mbengue Papa Ousmane Ba Mory Camara Soda Mareme Mbaye Moussa Seck Diop Jean Claude Dione Abdoul Khoudoss Diallo Moussa Mareme Samba Ibrahima Wade Anta Mbaye Sall Magaye Gaye Papa Adama Dieng Amadou Gabriel Ciss 《Surgical Science》 2025年第2期110-114,共5页
Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical managemen... Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical management of varicose pathology of the IM in Dakar. We enrolled 280 patients, with a mean age of 36 and a sex ratio of 2. Factors favouring venous disease were dominated by prolonged orthostatism and multiparity. The average consultation time was 6 years. The reasons for consultation were functional manifestations, progressive complications and aesthetics. The venous trunks concerned were the great saphenous vein (GSV) in 58.9% of cases, the small saphenous vein (SSV) in 29% of cases, perforating veins and varicose veins were unsystematized in 28.5% of cases. Surgery was performed under spinal anaesthesia. Surgical procedures were dominated by stripping of the GSV, crossectomy of the SSV and staged ligations. One patient developed meningismus immediately after the operation. Average follow-up was 2 years. Mortality was null. 展开更多
关键词 Varicose veins Lower Limbs STRIPPING
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Study on the Efficacy of Radiofrequency and Laser Ablation in the Treatment of Superficial Varicose Veins in the Lower Extremities
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作者 Qingshan Wang 《Journal of Clinical and Nursing Research》 2025年第1期181-187,共7页
Objective: To evaluate the efficacy of endovenous radiofrequency ablation (RFA) and laser ablation (EVLA) in the treatment of superficial varicose veins of the lower extremities. Methods: Seventy-eight patients with s... Objective: To evaluate the efficacy of endovenous radiofrequency ablation (RFA) and laser ablation (EVLA) in the treatment of superficial varicose veins of the lower extremities. Methods: Seventy-eight patients with superficial varicose veins treated at a hospital between April 2022 and May 2023 were selected and divided into a radiofrequency ablation group (RFA group;39 cases) and a laser ablation group (EVLA group;39 cases) based on the treatment method. Operation time, postoperative recovery duration, venous clinical severity score (VCSS) changes, complication rates, closure rates, and recurrence rates were compared between the groups at 1 month, 3 months, and 12 months postoperatively. The postoperative therapeutic outcomes were comprehensively evaluated. Results: No significant differences in age, gender, disease grade, or disease course were observed between the groups (P > 0.05). The superficial varicose vein closure rate was 100% in both groups at 1 and 3 months postoperatively. At 12 months, the closure rate was 94.87% in the RFA group and 97.43% in the EVLA group, with no statistically significant difference (P > 0.05). No significant differences were observed in VCSS changes or complication incidence between the groups (P > 0.05). Conclusion: Radiofrequency ablation and laser ablation demonstrate comparable efficacy and safety in the treatment of superficial varicose veins of the lower extremities. 展开更多
关键词 Radiofrequency ablation Laser ablation Superficial varicose veins Closure rate COMPLICATIONS
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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization
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作者 ZHANG Huichao CHAI Peng +2 位作者 ZHANG Hongrui ZHOU Limin HOU Zengqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期104-116,共13页
Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mi... Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in Zhenyuan.Therefore,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold deposits.Phlogopite in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in lamprophyres.The in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from lamprophyres.High large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched mantle.Kfeldspar veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit. 展开更多
关键词 LAMPROPHYRE K-feldspar vein apatite Sr isotope gold Zhenyuan deposit YUNNAN
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Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China
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作者 Guan-Min Wang Yun-Jiao Zhang +3 位作者 Zi-Yuan Yin Rui Zhu Zhi-Yao Hou Yu Bai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1508-1523,共16页
Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving f... Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history. 展开更多
关键词 Calcite veins Shale diagenesis Material source Formation period Formation mechanism
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Modeling Blood Flow in Veins of Uniform Properties (Giraffe Jugular Vein)
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作者 Rogers Omboga Amenya Johanna Kibet Sigey +1 位作者 Geoffrey Moriaso Ole Maloiy David Mwangi Theuri 《Open Journal of Biophysics》 2024年第2期132-153,共22页
This paper models the giraffe’s jugular veins as a uniform collapsible tube from a rigid skull. The equations governing one-dimensional steady flow through such a tube for various conditions have been developed. The ... This paper models the giraffe’s jugular veins as a uniform collapsible tube from a rigid skull. The equations governing one-dimensional steady flow through such a tube for various conditions have been developed. The effects of inertial and inclination angles that have not been discussed previously have been included. It has been shown that different flows for a uniform tube (vein) are possible. However, this flow matches that of a jugular vein which is supercritical, and the steady solution has been given by the balance between the driving forces of gravity and the viscous resistance to the flow at the right atrium of the heart must be sub-critical for a fixed right-atrium pressure which means that an elastic jump is required to return the flow to sub-critical from the supercritical flow upstream this type of relationship gives rise to flow limitation at the same time given any right atrium fixed pressure there exists a maximum flow rate which when exceeded the boundary conditions of the flow do not hold boundary conditions at the right atrium are not satisfied hence making the steady flow impossible this mechanism of flow limitation is slightly different from the other one in that causes airways through forced expiration from the observation made it is clearly shown that there is an intravascular pressure difference with a change in height. 展开更多
关键词 Blood Flow Jugular vein Cross-Sectional Area SUPERCRITICAL SUBCRITICAL JUMP
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Sclerotherapy as the Only Treatment for Varicose Veins
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作者 Moaath Al-Smady Qutaiba AbuQuba +4 位作者 Ahmad Al-Saraheen Basil Al-Azaideh Malik Allahham Zeenah Alsmady Amjad Bani Hani 《World Journal of Cardiovascular Surgery》 2024年第10期166-180,共15页
Background: Chronic venous insufficiency (CVI) is a widespread and underdiagnosed condition that affects more than 20% of the general population. The most prevalent manifestation of CVI is varicose veins (VVs), which ... Background: Chronic venous insufficiency (CVI) is a widespread and underdiagnosed condition that affects more than 20% of the general population. The most prevalent manifestation of CVI is varicose veins (VVs), which affect up to 25% of women and 15% of males. Sclerotherapy is a minimally invasive procedure used primarily in treating telangiectasias, reticular veins, and small varicose veins. Objectives: This study aims to evaluate the efficacy and safety of various sclerotherapy techniques in treating varicose veins-related complications. Methods: We conducted a cross-sectional observational interventional study at Jordan University Hospital (JUH) from September 2022 to January 2023. The study involved patients with lower limb varicose veins, assessing their clinical response and monitoring potential treatment complications. Statistical analyses were performed using SPSS software version 21.0. Results: Of 567 patients with diagnosed VVs, 544 were female (95.94%), and 23 were male (4.06%). The primary complaints were pain and cosmetic concerns. Treatments included Foam Aethoxysklerol® 3% (polidocanol) and Micro-foam Aethoxysklerol® 1%. Improvement in symptoms was reported by 538 patients (94.89%). The most common adverse event was hyperpigmentation, reported in 120 patients (21.16%), followed by post-procedural pain in 104 patients (18.34%). Notably, one patient (0.18%) experienced deep vein thrombosis (DVT), one (0.18%) reported telangiectatic matting, and there were two cases (0.36%) of visual disturbances and one allergic reaction. Conclusion: Sclerotherapy is effective and safe for treating VVs with minimal adverse events. It is a viable standalone treatment, reducing complications linked to other methods like radiofrequency ablation and surgery. 展开更多
关键词 Chronic Venous Insufficiency Foam Sclerotherapy Varicose veins Adverse Events
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Benefit in physical function and quality of life to nonsurgical treatment of varicose veins: Pilot study
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作者 Gwon-Min Kim BoKun Kim +5 位作者 Minwoo Jang Jong-Hwan Park Miju Bae Chung Won Lee Jong Won Kim Up Huh 《World Journal of Clinical Cases》 SCIE 2024年第3期517-524,共8页
BACKGROUND Studies on varicose veins have focused its effects on physical function;however,whether nonsurgical treatments alter muscle oxygenation or physical function remains unclear.Moreover,the differences in such ... BACKGROUND Studies on varicose veins have focused its effects on physical function;however,whether nonsurgical treatments alter muscle oxygenation or physical function remains unclear.Moreover,the differences in such functions between individuals with varicose veins and healthy individuals remain unclear.AIM To investigate changes in physical function and the quality of life(QOL)following nonsurgical treatment of patients with varicose veins and determine the changes in their muscle oxygenation during activity.METHODS We enrolled 37 participants(those with varicose veins,n=17;healthy individuals,n=20).We performed the following measurements pre-and post-nonsurgical treatment in the varicose vein patients and healthy individuals:Calf muscle oxygenation during the two-minute step test,open eyes one-leg stance,30 s sit-to-stand test,visual analog scale(VAS)for pain,Pittsburgh sleep quality index,physical activity assessment,and QOL assessment.RESULTS Varicose veins patients and healthy individuals differ in most variables(physical function,sleep quality,and QOL).Varicose veins patients showed significant differences between pre-and post-nonsurgical treatment—results in the 30 sit-to-stand test[14.41(2.45)to 16.35(4.11),P=0.018],two-minute step test[162.29(25.98)to 170.65(23.80),P=0.037],VAS for pain[5.35(1.90)to 3.88(1.73),P=0.004],and QOL[39.34(19.98)to 26.69(17.02),P=0.005];however,no significant difference was observed for muscle oxygenation.CONCLUSION Nonsurgical treatment improved lower extremity function and QOL in varicose veins patients,bringing their condition close to that of healthy individuals.Future studies should include patients with severe varicose veins requiring surgery to confirm our findings. 展开更多
关键词 Varicose vein Nonsurgical treatment Physical function Quality of life Near infrared spectroscopy
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Multidetector computer tomography and magnetic resonance imaging of double superior mesenteric veins:A case report
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作者 Wei Tang Song Peng 《World Journal of Clinical Cases》 SCIE 2024年第17期3265-3270,共6页
BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMA... BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMARY We describe the case of a 34-year-old male,who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis.MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein(SMV),the double SMVs.CONCLUSION The double SMVs are a congenital abnormality without potential clinical manifestation.Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury. 展开更多
关键词 Superior mesenteric vein Anatomic variation Magnetic resonance imaging Multidetector computer tomography Case report
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Genetic mechanism and petroleum geological significance of calcite veins in organic-rich shales of lacustrine basin:A case study of Cretaceous Qingshankou Formation in Songliao Basin,China
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作者 HE Wenyuan SUN Ningliang +3 位作者 ZHANG Jinyou ZHONG Jianhua GAO Jianbo SHENG Pengpeng 《Petroleum Exploration and Development》 SCIE 2024年第5期1083-1096,共14页
Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological sign... Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological significance of calcite veins in shales of the Cretaceous Qingshankou Formation in the Songliao Basin were investigated.Macroscopically,the calcite veins are bedding parallel,and show lenticular,S-shaped,cone-in-cone and pinnate structures.Microscopically,they can be divided into syntaxial blocky or columnar calcite veins and antitaxial fibrous calcite veins.The aqueous fluid inclusions in blocky calcite veins have a homogenization temperature of 132.5–145.1℃,the in-situ U-Pb dating age of blocky calcite veins is(69.9±5.2)Ma,suggesting that the middle maturity period of source rocks and the conventional oil formation period in the Qingshankou Formation are the sedimentary period of Mingshui Formation in Late Cretaceous.The aqueous fluid inclusions in fibrous calcite veins with the homogenization temperature of 141.2–157.4℃,yields the U-Pb age of(44.7±6.9)Ma,indicating that the middle-high maturity period of source rocks and the Gulong shale oil formation period in the Qingshankou Formation are the sedimentary period of Paleocene Yi'an Formaiton.The syntaxial blocky or columnar calcite veins were formed sensitively to the diagenetic evolution and hydrocarbon generation,mainly in three stages(fracture opening,vein-forming fluid filling,and vein growth).Tectonic extrusion activities and fluid overpressure are induction factors for the formation of fractures,and vein-forming fluid flows mainly as diffusion in a short distance.These veins generally follow a competitive growth mode.The antitaxial fibrous calcite veins were formed under the driving of the force of crystallization in a non-competitive growth environment.It is considered that the calcite veins in organic-rich shale of the Qingshankou Formation in the study area has important implications for local tectonic activities,fluid overpressure,hydrocarbon generation and expulsion,and diagenesis-hydrocarbon accumulation dating of the Songliao Basin. 展开更多
关键词 Songliao Basin calcite vein in-situ LA-ICP-MS U-Pb dating horizontal extrusion force of crystallization OVERPRESSURE shale oil CRETACEOUS Qingshankou Formation
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Automatic Detection and Characterization of Human Veins Using Infra-Red Image Processing
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作者 Jean Ndoumbe Brice Ekobo Akoa +3 位作者 Gaelle Patricia Talotsing Frederic Franck Kounga Samuel Kaissassou Bertin Chouanmo Njo 《Journal of Computer and Communications》 2024年第9期141-159,共19页
The detection and characterization of human veins using infrared (IR) image processing have gained significant attention due to its potential applications in biometric identification, medical diagnostics, and vein-bas... The detection and characterization of human veins using infrared (IR) image processing have gained significant attention due to its potential applications in biometric identification, medical diagnostics, and vein-based authentication systems. This paper presents a low-cost approach for automatic detection and characterization of human veins from IR images. The proposed method uses image processing techniques including segmentation, feature extraction, and, pattern recognition algorithms. Initially, the IR images are preprocessed to enhance vein structures and reduce noise. Subsequently, a CLAHE algorithm is employed to extract vein regions based on their unique IR absorption properties. Features such as vein thickness, orientation, and branching patterns are extracted using mathematical morphology and directional filters. Finally, a classification framework is implemented to categorize veins and distinguish them from surrounding tissues or artifacts. A setup based on Raspberry Pi was used. Experimental results of IR images demonstrate the effectiveness and robustness of the proposed approach in accurately detecting and characterizing human. The developed system shows promising for integration into applications requiring reliable and secure identification based on vein patterns. Our work provides an effective and low-cost solution for nursing staff in low and middle-income countries to perform a safe and accurate venipuncture. 展开更多
关键词 vein Detection Blood Radiation Infrared Image CLAHE Algorithm Raspberry Pi
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Case Report: Leiomyosarcoma Originating from the Gonadal Vein
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作者 Vithiarithy Chey Neang Nov +5 位作者 Koung Tep Vitou Leang Reaksmey Chhay Dimanche Chhit Tharuom Ny Keoseyla Unn 《Open Journal of Gastroenterology》 2025年第2期57-67,共11页
Leiomyosarcoma of the gonadal vein is an exceedingly rare entity, representing a small subset of smooth muscle tumors that more commonly arise in the retroperitoneum, uterus, and blood vessels. To date, fewer than 10 ... Leiomyosarcoma of the gonadal vein is an exceedingly rare entity, representing a small subset of smooth muscle tumors that more commonly arise in the retroperitoneum, uterus, and blood vessels. To date, fewer than 10 cases of gonadal vein leiomyosarcoma have been reported in the literature, highlighting its rarity and the limited understanding of its clinical behavior. These tumors are often diagnosed incidentally or present with nonspecific symptoms, such as abdominal pain or a palpable mass, which can complicate early detection. The proximity of gonadal vein leiomyosarcomas to critical structures, such as the ureter, renal vessels, and surrounding organs, introduces unique diagnostic and surgical challenges. Previous reports have underscored the importance of advanced imaging techniques, including CT and MRI, in delineating the tumor’s anatomical relationships and guiding surgical planning. This case, involving a leiomyosarcoma closely associated with the patient’s left ureter, provides an opportunity to build on existing knowledge by addressing the clinical presentation, diagnostic approach, treatment pathway, and long-term follow-up strategies required for optimal management. By presenting this detailed review, we aim to contribute valuable insights into the diagnosis and management of this rare malignancy. 展开更多
关键词 LEIOMYOSARCOMA Gonadal vein Rare Tumor Smooth Muscle Tumor Diagnostic Challenges Multidisciplinary Management
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Predicting post-hepatectomy liver failure using a nomogram based on portal vein width,inflammatory indices,and the albumin-bilirubin score
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作者 Ke Sun Jiang-Bin Li +3 位作者 Ya-Feng Chen Zhong-Jie Zhai Lang Chen Rui Dong 《World Journal of Gastrointestinal Surgery》 2025年第2期87-96,共10页
BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identif... BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identify potential high-risk PHLF patients as early as possible through preoperative evaluation.AIM To identify risk factors for PHLF and develop a prediction model.METHODS This study included 248 patients with HCC at The Second Affiliated Hospital of Air Force Medical University between January 2014 and December 2023;these patients were divided into a training group(n=164)and a validation group(n=84)via random sampling.The independent variables for the occurrence of PHLF were identified by univariate and multivariate analyses and visualized as nomograms.Ultimately,comparisons were made with traditional models via receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS In this study,portal vein width[odds ratio(OR)=1.603,95%CI:1.288-1.994,P≤0.001],the preoperative neutrophil-to-lymphocyte ratio(NLR)(OR=1.495,95%CI:1.126-1.984,P=0.005),and the albumin-bilirubin(ALBI)score(OR=8.868,95%CI:2.144-36.678,P=0.003)were independent risk factors for PHLF.A nomogram prediction model was developed using these factors.ROC and DCA analyses revealed that the predictive efficacy and clinical value of this model were better than those of traditional models.CONCLUSION A new Nomogram model for predicting PHLF in HCC patients was successfully established based on portal vein width,the NLR,and the ALBI score,which outperforms the traditional model. 展开更多
关键词 NOMOGRAM Hepatocellular carcinoma Post-hepatectomy liver failure Albumin-bilirubin score Portal vein width
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Comparison of the effect of ranibizumab in retinal vein occlusion and macular edema with different optical coherence tomographic patterns
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作者 Yue Xu Yue-Cong Yin +3 位作者 Ze-Yu Song Xiao-Yu Zhou Jia-Ju Zhang Juan Liang 《International Journal of Ophthalmology(English edition)》 2025年第2期275-282,共8页
AIM:To explore the morphological and functional parameters to evaluate the effectiveness of intravitreal injections of ranibizumab(IVR)in treating macular edema(ME)secondary to retinal vein occlusion(RVO).METHODS:This... AIM:To explore the morphological and functional parameters to evaluate the effectiveness of intravitreal injections of ranibizumab(IVR)in treating macular edema(ME)secondary to retinal vein occlusion(RVO).METHODS:This retrospective study involved 65 RVO patients(65 eyes)who received IVR and were followedup for more than 3mo.ME was categorized into cystoid macular edema(CME),diffuse retinal thickening(DRT),and serous retinal detachment(SRD)according to optical coherence tomography(OCT)images.The comparison of best corrected visual acuity(BCVA;logMAR)and central macular thickness(CMT)among different follow-up points and those among 3 groups were performed by Kruskal-Wallis test.The correlation between BCVA and baseline parameters during treatment was analyzed using Spearman correlation analysis.RESULTS:BCVA tended to improve in all groups,with marked improvement in CME and DRT groups.CMT showed the greatest reduction after 1wk,and remained stable over the following 3mo.DRT patients had the worst BCVA and the highest CMT at baseline,but the differences became smaller after IVR treatment.CMT in SRD group was significantly better than in CME and DRT groups 3mo after IVR.Most patients of CME and SRD groups transitioned to a normal pattern at 3mo follow-up.DRT patients were most likely to transform into the other morphological groups,while SRD patients showed minimal transitions.BCVA at baseline was identified as the most important prognostic indicator in all 3 groups.Additionally,DRT patients with a longer clinical course,higher CMT and central retinal vein occlusion(CRVO)tend to exhibit worse BCVA after treatment.In addition,CRVO patients are more likely to have worse BCVA at 2 and 3mo follow-up compared with branch retinal vein occlusion(BRVO)patients in CME group.SRD patients with higher baseline CMT were prone to experiencing worse BCVA after treatment.CONCLUSION:The effectiveness of IVR is strongly correlated with baseline BCVA in all 3 groups.Baseline parameters including clinical course,CMT,and RVO position are also useful in predicting the BCVA at different time points after treatment. 展开更多
关键词 retinal vein occlusion optical coherence tomography serous retinal detachment cystoid macular edema diffuse retinal thickening
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Subduction channel fluid-rock interaction:Indications from rutile-quartz veins within eclogite from the Yuka terrane,North Qaidam orogen 被引量:5
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作者 Xin Chen Youye Zheng +5 位作者 Rongke Xu Pingyang Gu Jiyuan Yu Jie Bai Pengjie Cai Xiaojia Jiang 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期635-650,共16页
High-pressure(HP)or ultrahigh-pressure(UHP)rutile-quartz veins that form at mantle depths due to fluid-rock interaction can be used to trace the properties and behavior of natural fluids in subduction zones.To explore... High-pressure(HP)or ultrahigh-pressure(UHP)rutile-quartz veins that form at mantle depths due to fluid-rock interaction can be used to trace the properties and behavior of natural fluids in subduction zones.To explore the fluid flow and the associated element mobility during deep subduction and exhumation of the continental crust,we investigated the major and trace elements of Ti-rich minerals.Additionally,U–Pb dating,trace element contents,and Lu–Hf isotopic composition of zircon grains in the UHP eclogite and associated rutile-quartz veins were examined in the North Qaidam UHP metamorphic belt,Yuka terrane.The zircon grains in the rutile-quartz veins have unzoned or weak oscillatory zonings,and show low Th/U ratios,steep chondrite-normalized patterns of heavy rare earth elements(HREEs),and insignificant negative Eu anomalies,indicating their growth in metamorphic fluids.These zircon grains formed in 4313 Ma,which is consistent with the 4322 Ma age of the host eclogite.As for the zircons in the rutile-quartz veins,they showed steep HREE patterns on one hand,and were different from the zircons present in the host eclogite on the other.This demonstrates that their formation might have been related to the breakdown of the early stage of garnet,which corresponds to the abundance of fluids during the early exhumation stage.The core-rim profile analyses of rutile recorded a two-stage rutile growth across a large rutile grain;the rutile core has higher Nb,Ta,W,and Zr contents and lower Nb/Ta ratios than the rim,indicating that the rutile domains grew in different metamorphic fluids from the core towards the rim.The significant enrichment of high field strength elements(HFSEs)in the rutile core suggests that the peak fluids have high solubility and transportation capacity of these HFSEs.Furthermore,variations in the Nb vs.Cr trends in rutile indicate a connection of rutile to mafic protolith.The zircon grains from both the rutile-quartz veins and the host eclogite have similar Hf isotopic compositions,indicating that the vein-forming fluids are internally derived from the host eclogite.These fluids accumulated in the subduction channel and were triggered by local dehydration of the deeply subducted eclogite during the early exhumation conditions. 展开更多
关键词 quartz-rutile veins ECLOGITE Fluid-rock interaction Fluid flow Yuka North Qaidam
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Construction of Anti-breaking Models of the Main Veins of Flue-cured Tobacco Leaves and Principal Component Analysis 被引量:4
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作者 王宝玉 孙婷婷 +3 位作者 章国顺 张蜀香 阮龙 张云华 《Agricultural Science & Technology》 CAS 2011年第11期1615-1616,1656,共3页
[Objective] This study aimed to explore the related mechanisms of the breaking of flue-cured tobacco leaves. [Method] Anti-breaking models of the main veins of flue-cured tobacco leaves were constructed for principal ... [Objective] This study aimed to explore the related mechanisms of the breaking of flue-cured tobacco leaves. [Method] Anti-breaking models of the main veins of flue-cured tobacco leaves were constructed for principal component analysis on the anti-breaking index, leaf traits and cellulose contents. [Result] The results showed that the growth traits had certain relevance with the cellulose contents while the leaf weight assumed a significant negative correlation with the anti-breaking index, indicating that the heavier the leaf weight was, the weaker the anti-breaking capacity of flue-cured tobacco would be; the cross-sectional area of main veins and the cellulose contents had shown a positive correlation with the anti-breaking index, indicating that the thicker the main vein of flue-cured tobacco was, the higher the cellulose contents would be, and the stronger the anti-breaking capacity of flue-cured tobacco leaves would be. [Conclusion] This study provided theoretical basis and reference to improve tobacco production and enhance the quality of flue-cured tobacco. 展开更多
关键词 Flue-cured tobacco Main vein Anti-breaking index Principal component analysis
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基于Veins的交通路径优化算法研究
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作者 刘琨 《信息技术》 2022年第5期118-122,127,共6页
智能交通系统是未来智慧城市中不可缺少的一部分,而交通路径优化是智能交通重要的组成部分。文中主要研究了在Veins平台中交通路径优化算法。通过VANET(车载自组网)每台车辆都在同一个局域网互连互通,当前车遇到拥堵时通过拥塞躲避机制... 智能交通系统是未来智慧城市中不可缺少的一部分,而交通路径优化是智能交通重要的组成部分。文中主要研究了在Veins平台中交通路径优化算法。通过VANET(车载自组网)每台车辆都在同一个局域网互连互通,当前车遇到拥堵时通过拥塞躲避机制不断通知后方车辆,后方车辆通过设计的路径规划算法进行路径变更,直至拥堵结束。通过分析车辆通过的情况和交通数据,不断优化算法,最终达到减缓拥堵和提高交通效率的目的。 展开更多
关键词 veins 路径规划 拥塞躲避 优化算法 交通优化
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Persistent and advanced reddening of sweetgum leaves after major veins severing
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作者 王斐 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期465-468,524,共5页
The effects of major veins severing on morphological and physiological features of sweetgum (Liquidambar styraciflua L.) leaves were investigated by observing leaf color change and measuring leaf temperature, green/... The effects of major veins severing on morphological and physiological features of sweetgum (Liquidambar styraciflua L.) leaves were investigated by observing leaf color change and measuring leaf temperature, green/luminance (G/L) value of half-lobes, leaf stomata conductance, and water content in Yamaguchi University, Japan. The palmately veined leaves of sweetgum (Liquidambar styraciflua L.) were found more sensitive to the major vein severing than that of other species Major veins severing resulted in serious water stresses, as indicated by the persistent reddening and/or advanced reddening of local leaf, lower leaf stomatal conductance, and higher leaf temperature, etc. Severed leaf can be clearly divided into non-severed area, transitional area, and stressed area, which the three areas have different colours and temperature. The major vein barrier can also be seen clearly. The persistent reddening and advanced reddening seem consistent with the phenomenon of red crown top of some sweetgum trees and may have similar mechanism. 展开更多
关键词 advanced reddening G/L value leaf vein severing persistent reddening red top crown stomatal conductance SWEETGUM water stress
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Clinical studies on inferior right hepatic veins 被引量:7
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作者 Xing, Xue Li, Hong Liu, Wei-Guo 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第6期579-584,共6页
BACKGROUND: Many small veins are called accessory, short hepatic veins in addition to the right, middle and left hepatic veins. The size of these veins varied from a pinhole to 1 cm; the size of inferior right hepatic... BACKGROUND: Many small veins are called accessory, short hepatic veins in addition to the right, middle and left hepatic veins. The size of these veins varied from a pinhole to 1 cm; the size of inferior right hepatic veins (IRHVs) is thicker than that of short hepatic veins or more than 1 cm. occasionally. Adults have a higher incidence rate of the IRHV. DATA SOURCES: A literature search of the PubMed database was conducted and research articles were reviewed. RESULTS: The size of IRHVs is related to the size of the right hepatic vein, i.e. the larger the diameter of the right hepatic vein, the smaller the diameter of the IRHVs, and vice versa. The IRHVs are divided into superior, medial and inferior groups, separately named the superior, medial and inferior right hepatic veins according to the position of the IRHV entering the inferior vena cava. The superior right hepatic vein mainly drains the superior part of segment VII, and the medial right hepatic vein drains the middle part of segment VII. A thicker IRHV mainly drains segment VI and the inferior part of segment VII and a thinner IRHV drains the inferior part of segment V. CONCLUSIONS: The clinical significance of these studies on IRHVs is varied: (1) Hepatic caudate lobe resection could be introduced after study on the veins of that lobe. (2) It is very important to identify the draining region of the IRHV for guiding hepatic segmentectomy. The postero-inferior area of the right lobe can be preserved along with the hypertrophic IRHV even if the entire main right hepatic vein is resected during segmentectomy of VII and VIII with right hepatic vein resection for patients with primary liver cancer. (3) The ligation of the major hepatic vein for the treatment of juxtahepatic vein injury is recommended because of severe hemorrhagic shock and difficulty in exposure. (4) It is very helpful to decide therapeutic modalities for Budd-Chiari syndrome. 展开更多
关键词 hepatic vein inferior right hepatic vein HEPATECTOMY ANATOMY hepatic vein injury
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U-Pb SHRIMP Dating of Zircon from Quartz Veins of the Yangshan Gold Deposit in Gansu Province and Its Geological Significance 被引量:14
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作者 QIJinzhong YUANShisong +5 位作者 LIUZhijie LIUDunyi WANGYanbin LIZhihong GUOJunhua SUNBin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期443-451,共9页
The Yangshan gold deposit is a super-large fine-grained disseminated gold deposit located in southern Gansu Province. Its metallogenic age has been determined by using the cathodoluminescence image and ion probe U-Pb ... The Yangshan gold deposit is a super-large fine-grained disseminated gold deposit located in southern Gansu Province. Its metallogenic age has been determined by using the cathodoluminescence image and ion probe U-Pb dating techniques. It is found that zircons from quartz veinlet of the fine-grained disseminated gold ore show characters of magmatic origin with prism idiomorphism, oscillatory zoning and dominant Th/U ratios of 0.5-1.5. Three main populations of zircons are obtained, giving average 206Pb/238U ages of 197.6±1.7 Ma, 126.9±3.2 Ma and 51.2±1.3 Ma respectively. The first age corresponds to the K-Ar age of the plagiogranite dike, while the latter two ages indicate that buried Cretaceous and Tertiary intrusives exist in the orefield, suggesting that the Yangshan gold deposit was genetically related to the three magmatic hydrothermal activities. By contrast, zircons from coarse gold-bearing quartz vein in the mining area are much older than the host rock, indicating that the vein was formed earlier and was not contaminated by later magmatic fluids. It is concluded that the coupling of multiperiodic hydrothermal activities in the mining area has contributed a lot to mineralization of the Yangshan gold deposit. 展开更多
关键词 disseminated type gold deposit quartz vein SHRIMP dating cathodoluminescence image GANSU
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Early control of short hepatic portal veins in isolated or combined hepatic caudate lobectomy 被引量:11
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作者 Wan-Yee Lau 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第4期377-382,共6页
BACKGROUND:Caudate lobectomy has long been considered technically difficult.This study aimed to elaborate the significance of early control of short hepatic portal veins(SHPVs) in isolated hepatic caudate lobectomy or... BACKGROUND:Caudate lobectomy has long been considered technically difficult.This study aimed to elaborate the significance of early control of short hepatic portal veins(SHPVs) in isolated hepatic caudate lobectomy or in hepatic caudate lobectomy combined with major partial hepatectomy,and to describe the anatomical characteristics of SHPVs.METHODS:The data of 117 patients who underwent either isolated or combined caudate lobectomy by the same team of surgeons from 2005 to 2009 were retrospectively analyzed.From 2005 to 2007(group A,n=55),we carried out early control of short hepatic veins(SHVs) only;from 2008 to 2009(group B,n=62),we carried out early control of both SHVs and SHPVs.The two groups were compared to evaluate which surgical procedure was better.A detailed anatomical study was then carried out on the last 25 consecutive patients in group B to study the number and distribution of SHPVs during surgery.RESULTS:Patients in group B had less intra-operative blood loss,less impairment of liver function,shorter postoperative hospital stay,fewer postoperative complications and required less blood transfusion(P<0.05).The number of SHPVs in the 25 patients was 183,with 7.3±2.7 per patient.The diameters of SHPVs were 1 to 4 mm.On average,3.4 SHPVs/patient came from the left portal vein,2.2 from the bifurcation,1.4 from the right portal vein,and 0.3 from the main portal vein.On average,3.3 SHPVs/patient supplied segment I of the liver,0.4 for segment II,2.1 for segment IV,1.4 for segment V and 0.1 for segment VI.CONCLUSION:Early control of SHPVs in isolated or combined hepatic caudate lobectomy may be a useful method to decrease surgical risk and improve postoperative recovery. 展开更多
关键词 short hepatic portal vein caudate lobe ANATOMY
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