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Comparative analysis of empirical and deep learning models for ionospheric sporadic E layer prediction
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作者 BingKun Yu PengHao Tian +6 位作者 XiangHui Xue Christopher JScott HaiLun Ye JianFei Wu Wen Yi TingDi Chen XianKang Dou 《Earth and Planetary Physics》 EI CAS 2025年第1期10-19,共10页
Sporadic E(Es)layers in the ionosphere are characterized by intense plasma irregularities in the E region at altitudes of 90-130 km.Because they can significantly influence radio communications and navigation systems,... Sporadic E(Es)layers in the ionosphere are characterized by intense plasma irregularities in the E region at altitudes of 90-130 km.Because they can significantly influence radio communications and navigation systems,accurate forecasting of Es layers is crucial for ensuring the precision and dependability of navigation satellite systems.In this study,we present Es predictions made by an empirical model and by a deep learning model,and analyze their differences comprehensively by comparing the model predictions to satellite RO measurements and ground-based ionosonde observations.The deep learning model exhibited significantly better performance,as indicated by its high coefficient of correlation(r=0.87)with RO observations and predictions,than did the empirical model(r=0.53).This study highlights the importance of integrating artificial intelligence technology into ionosphere modelling generally,and into predicting Es layer occurrences and characteristics,in particular. 展开更多
关键词 ionospheric sporadic E layer radio occultation ionosondes numerical model deep learning model artificial intelligence
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In the Turmoil of the Cybercriminal Triad, Occult Practices and Toxicomania: The Case of a Young Ivorian Cyber Crook
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作者 Yves Stephane Ipou Bla Désirée Sandrine Ziketo +3 位作者 Dion Aristide Gonce Gnonsian Estelle Kévine Gahy Asseman Médard Koua Yessonguilana Jean-Marie Yeo-Tenena 《Open Journal of Psychiatry》 2024年第S1期457-466,共10页
Far from the financial gains of cyber crooks, the informed observer will see in cyber crookery a complex field of psychopathological expression where addictions and ritualistic practices intermingle. We thus carried o... Far from the financial gains of cyber crooks, the informed observer will see in cyber crookery a complex field of psychopathological expression where addictions and ritualistic practices intermingle. We thus carried out a qualitative observational study, focusing on a young Ivorian cyber-escroc, hard drug user and follower of mystical practices taken in charge by a multidisciplinary team during a resocialization course for children in conflict with the law from November to December 2022. The aim was to describe the difficulties experienced by a young Ivorian cyber crook in escaping the clutches of occult practices, internet addictions and psychoactive substances encountered in the field of cyber crookery. KA is confronted with the problem of cybercrime associated with occult practices and drug addiction. He is a heroin addict and secondary internet addict, undergoing de facto detoxification and presenting risky consumption behaviors. His fear is fuelled by the sudden death of his childhood friend, who introduced him to cyber-scams and occult practices, and the impossibility of returning his “Agbaladai” fetish when he can no longer honor the weekly sacrifices. Our results show an interweaving of psychopathological entities, namely cyberaddiction and addiction to psychoactive substances, against a backdrop of mystico-cultural practices and interpretations. 展开更多
关键词 CYBERCRIME Internet Addiction Heroin Addiction occultism
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Clinicopathological features,psychological status,and prognosis of 33 patients with occult breast cancer 被引量:1
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作者 Hong-Mei Wang Ao-Yang Yu +6 位作者 Lin-Lin Li Lu-Yao Ma Meng-Han Cao Yu-Le Yang Xiao-Bing Qin Juan-JuanTang Zheng-Xiang Han 《World Journal of Psychiatry》 SCIE 2024年第1期76-87,共12页
BACKGROUND Occult breast cancer(OBC)has traditionally been considered to be a carcinoma of unknown primary origin with a favorable prognosis and can be treated as stage II-III breast cancer.Due to the small number of ... BACKGROUND Occult breast cancer(OBC)has traditionally been considered to be a carcinoma of unknown primary origin with a favorable prognosis and can be treated as stage II-III breast cancer.Due to the small number of cases and limited clinical experience,treatments vary greatly around the world and no standardized treatment has yet been established.AIM To investigate the clinicopathological features,psychological status and prognostic features of patients with OBC.METHODS The clinicopathological data of 33 OBC patients diagnosed and treated in the Affiliated Hospital of Xuzhou Medical University and Xuzhou Central Hospital from November 2015 to November 2022 were retrospectively analyzed.The psychological status of OBC patients was evaluated by the Self-rating Anxiety Scale and Self-rating Depression Scale.Patients’emotions,stress perception and psychological resilience were evaluated by the Positive and Negative Affect Schedule,the Chinese Perceived Stress Scale,and the Connor-Davidson Resilience Scale(CD-RISC),respectively.Patient survival was calculated using the Kaplan-Meier method,and survival curves were plotted for analysis with the log-rank test.Univariate and multivariate survival analyses were performed using the Cox regression model.RESULTS The 33 OBC patients included 32 females and 1 male.Of the 33 patients,30(91%)had axillary tumors,3(9%)had a neck mass as the primary symptom;18(54.5%)had estrogen receptor-positive tumors,17(51.5%)had progesterone receptor-positive tumors,and 18(54.5%)had Her-2-positive tumors;24(72.7%)received surgical treatment,including 18 patients who underwent modified radical mastectomy,1 patient who underwent breast-conserving surgery plus axillary lymph node dissection(ALND),and 5 patients who underwent ALND alone;12 patients received preoperative neoadjuvant therapy.All 30 patients developed anxiety and depression,with low positive affect scores and high negative affect scores,accompanied by a high stress level and poor psychological resilience.There were no differences in the psychological status of patients according to age,body mass index,or menopausal status.The overall survival and disease-free survival(DFS)of all the patients were 83.3%and 55.7%,respectively.Univariate analysis demonstrated that the initial tumor site(P=0.021)and node stage(P=0.020)were factors that may affect patient prognosis.The 5-year DFS rate of OBC patients who received radiotherapy was greater(P<0.001),while the use of different surgical methods(P=0.687)had no statistically significant effect on patient outcomes.Multivariate analysis revealed that radiotherapy(P=0.031)was an independent prognostic factor.Receiving radiotherapy had a significant effect on the CD-RISC score(P=0.02).CONCLUSION OBC is a rare breast disease whose diagnosis and treatment are currently controversial.There was no significant difference in the efficacy of other less invasive surgical procedures compared to those of modified radical mastectomy.In addition,radiotherapy can significantly improve patient outcomes.We should pay attention to the psychological state of patients while they receive antitumor therapy. 展开更多
关键词 Occult breast cancer Breast cancer Perceived Stress Scale Axillary lymph node dissection
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Genetic diversity and occult hepatitis B infection in Africa: A comprehensive review 被引量:1
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作者 Michee M Bazie Mahamoudou Sanou +6 位作者 Florencia Wendkuuni Djigma Tegwinde Rebeca Compaore Dorcas Obiri-Yeboah Benoît Kabamba Bolni Marius Nagalo Jacques Simpore Rasmata Ouédraogo 《World Journal of Hepatology》 2024年第5期843-859,共17页
BACKGROUND Occult hepatitis B infection(OBI)is a globally prevalent infection,with its frequency being influenced by the prevalence of hepatitis B virus(HBV)infection in a particular geographic region,including Africa... BACKGROUND Occult hepatitis B infection(OBI)is a globally prevalent infection,with its frequency being influenced by the prevalence of hepatitis B virus(HBV)infection in a particular geographic region,including Africa.OBI can be transmitted th-rough blood transfusions and organ transplants and has been linked to the development of hepatocellular carcinoma(HCC).The associated HBV genotype influences the infection.AIM To highlight the genetic diversity and prevalence of OBI in Africa.METHODS This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and involved a comprehensive search on PubMed,Google Scholar,Science Direct,and African Journals Online for published studies on the prevalence and genetic diversity of OBI in Africa.RESULTS The synthesis included 83 articles,revealing that the prevalence of OBI varied between countries and population groups,with the highest prevalence being 90.9%in patients with hepatitis C virus infection and 38%in blood donors,indicating an increased risk of HBV transmission through blood transfusions.Cases of OBI reactivation have been reported following chemotherapy.Genotype D is the predominant,followed by genotypes A and E.CONCLUSION This review highlights the prevalence of OBI in Africa,which varies across countries and population groups.The study also demonstrates that genotype D is the most prevalent. 展开更多
关键词 Occult hepatitis B infection Blood transfusion Genetic diversity
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Research on internal gravity waves in the Martian atmosphere based on Tianwen-1 and Mars Global Surveyor occultation data
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作者 Luo Xiao CunYing Xiao +2 位作者 Xiong Hu ZeWei Wang XiaoQi Wu 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期890-898,共9页
Internal gravity waves(IGWs)are critical in driving Martian atmospheric motion and phenomena.This study investigates Martian IGWs by using high-resolution data from China’s Tianwen-1 mission and the National Aeronaut... Internal gravity waves(IGWs)are critical in driving Martian atmospheric motion and phenomena.This study investigates Martian IGWs by using high-resolution data from China’s Tianwen-1 mission and the National Aeronautics and Space Administration’s Mars Global Surveyor(MGS)by the radio occultation(RO)technique.Key IGW parameters,such as vertical and horizontal wavelengths,intrinsic frequency,and energy density,are extracted based on vertical temperature profiles from the Martian surface to~50 km altitude.Data reveal that the Martian IGWs are predominantly small-scale waves,with vertical wavelengths between 6 and 13 km and horizontal wavelengths extending to thousands of kilometers.These waves propagate almost vertically and exhibit low intrinsic frequencies close to the inertial frequency,with the characteristic of low-frequency inertial IGWs.Tianwen-1 data indicate stronger IGW activity,higher energy density,and less dissipation than MGS data in the northern hemisphere.Moreover,MGS data in the southern hemisphere show higher buoyancy frequencies and lower vertical wavelengths,suggesting more stable atmospheric conditions conducive to IGW propagation.These extracted IGW characteristics can enhance our understanding of the atmospheric dynamics on Mars and contribute valuable information for parameterization in global circulation models. 展开更多
关键词 internal gravity waves MARS Tianwen-1 Mars Global Surveyor radio occultation
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Early diagnostic strategies for colorectal cancer
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作者 Shi-Cai Liu Han Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第33期3818-3822,共5页
At present,cancer is still an important factor threatening human health.Colorectal cancer(CRC)is one of the top three most common cancers worldwide and one of the deadliest malignancies in humans.The latest data showe... At present,cancer is still an important factor threatening human health.Colorectal cancer(CRC)is one of the top three most common cancers worldwide and one of the deadliest malignancies in humans.The latest data showed that CRC incidence and mortality rank third and second,respectively,among global malignancies.Early and accurate diagnosis is crucial to reduce the morbidity,mortality and improve survival of patients with CRC,but the current early diagnostic methods have limitations.The effectiveness and compliance of diagnostic methods have a certain impact on whether people choose screening.In this editorial,we explore strategies for the early diagnosis of CRC,including stool-based,blood-based,direct visualization,and imaging examinations. 展开更多
关键词 Colorectal cancer Diagnostic markers COLONOSCOPY Fecal immunochemical test Fecal occult blood test Circulating tumor cells Circulating tumor DNA
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Early colorectal cancer screening–no time to lose
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作者 Ying Wang Zheng-Long Wu +2 位作者 Yi-Gang Wang Hui Wang Xiao-Yuan Jia 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期2959-2963,共5页
In this editorial,we comment on the article entitled“Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?”by Agatsuma et al.Colorectal cancer(CRC)is emerging as an important healt... In this editorial,we comment on the article entitled“Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?”by Agatsuma et al.Colorectal cancer(CRC)is emerging as an important health issue as its incidence continues to rise globally,adversely affecting the quality of life.Although the public has become more aware of CRC prevention,most patients lack screening awareness.Some poor lifestyle practices can lead to CRC and symptoms can appear in the early stages of CRC.However,due to the lack of awareness of the disease,most of the CRC patients are diagnosed already at an advanced stage and have a poor prognosis. 展开更多
关键词 Colorectal cancer The immunochemical fecal occult blood test Diagnostic route Cancer screening Stage at diagnosis
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Reactivation of hepatitis B virus infection – an important aspect of multifaceted problem
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作者 Sergey Morozov Sergey Batskikh 《World Journal of Gastroenterology》 SCIE CAS 2024年第26期3193-3197,共5页
In this editorial we comment on the article published in the recent issue of the W orld Journal of Gastroenterology.We focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of pr... In this editorial we comment on the article published in the recent issue of the W orld Journal of Gastroenterology.We focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of HBV.The prevalence of PHB is underestimated due to the lack of population testing programs.However,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune disorders.Here we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment. 展开更多
关键词 Occult hepatitis B virus infection Hepatitis B virus reactivation Previous hepatitis B CANCER Autoimmune disorders
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Effectiveness of colonoscopy,immune fecal occult blood testing,and risk-graded screening strategies in colorectal cancer screening
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作者 Ming Xu Jing-Yi Yang Tao Meng 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2270-2280,共11页
BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors,and early screening is crucial to improving the survival rate of patients.The combination of colonoscopy and immune fecal occult blood detect... BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors,and early screening is crucial to improving the survival rate of patients.The combination of colonoscopy and immune fecal occult blood detection has garnered significant attention as a novel method for CRC screening.Colonoscopy and fecal occult blood tests,when combined,can improve screening accuracy and early detection rates,thereby facilitating early intervention and treatment.However,certain risks and costs accompany it,making the establishment of a risk classification model crucial for accurate classification and management of screened subjects.AIM To evaluate the feasibility and effectiveness of colonoscopy,immune fecal occult blood test(FIT),and risk-graded screening strategies in CRC screening.METHODS Based on the randomized controlled trial of CRC screening in the population conducted by our hospital May 2020 to May 2023,participants who met the requirements were randomly assigned to a colonoscopy group,an FIT group,or a graded screening group at a ratio of 1:2:2(after risk assessment,the high-risk group received colonoscopy,the low-risk group received an FIT test,and the FITpositive group received colonoscopy).The three groups received CRC screening with different protocols,among which the colonoscopy group only received baseline screening,and the FIT group and the graded screening group received annual follow-up screening based on baseline screening.The primary outcome was the detection rate of advanced tumors,including CRC and advanced adenoma.The population participation rate,advanced tumor detection rate,and colonoscopy load of the three screening programs were compared.RESULTS A total of 19373 subjects who met the inclusion and exclusion criteria were enrolled,including 8082 males(41.7%)and 11291 females(58.3%).The mean age was 60.05±6.5 years.Among them,3883 patients were enrolled in the colonoscopy group,7793 in the FIT group,and 7697 in the graded screening group.Two rounds of follow-up screening were completed in the FIT group and the graded screening group.The graded screening group(89.2%)and the colonoscopy group(42.3%)had the lowest overall screening participation rates,while the FIT group had the highest(99.3%).The results of the intentional analysis showed that the detection rate of advanced tumors in the colonoscopy group was greater than that of the FIT group[2.76%vs 2.17%,odds ratio(OR)=1.30,95%confidence interval(CI):1.01-1.65,P=0.037].There was no significant difference in the detection rate of advanced tumors between the colonoscopy group and the graded screening group(2.76%vs 2.35%,OR=1.9,95%CI:0.93-1.51,P=0.156),as well as between the graded screening group and the FIT group(2.35%vs 2.17%,OR=1.09%,95%CI:0.88-1.34,P=0.440).The number of colonoscopy examinations required for each patient with advanced tumors was used as an index to evaluate the colonoscopy load during population screening.The graded screening group had the highest colonoscopy load(15.4 times),followed by the colonoscopy group(10.2 times),and the FIT group had the lowest(7.8 times).CONCLUSION A hierarchical screening strategy based on CRC risk assessment is feasible for screening for CRC in the population.It can be used as an effective supplement to traditional colonoscopy and FIT screening programs. 展开更多
关键词 Colorectal tumor Immune fecal occult blood testing COLONOSCOPY Hierarchical screening Risk assessment
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Hepatitis B surface antigen-negative but hepatitis B envelope antigen-positive false occult hepatitis B virus infection:A case report
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作者 Shu-Sheng Yang Fei Fu +4 位作者 Qian-Kun Xuan Zhou-Xiang Zhang Zhi-Jun Li Guang-Bo Li Xiao-Yu Yu 《World Journal of Hepatology》 2024年第10期1199-1207,共9页
BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The d... BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels. 展开更多
关键词 Occult hepatitis B infection Hepatitis B virus Hepatitis B surface antigen Hepatitis B envelope antigen Immunodominant epitopes Case report
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Yeats’s Ideals:Women Old and Young
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作者 DONG Qian 《Journal of Literature and Art Studies》 2024年第5期330-334,共5页
William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,... William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,Lady Gregory,and Georgie Hyde-Lees.Even in Yeats’s poetry involved with symbolism,it is worth noting that his employment of symbols has used these women as the archetypes,and that the historical context rendered Yeats’s representations of them in his poetry all the more interesting. 展开更多
关键词 IDEALS WOMEN representation SYMBOLISM OCCULT
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Chronic hepatitis B and occult infection in chemotherapy patients-evaluation in oncology and hemato-oncology settings:The CHOICE study
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作者 Nayana Sudevan Manish Manrai +2 位作者 T V S V G K Tilak Harshit Khurana Harikrishnan Premdeep 《World Journal of Virology》 2024年第1期61-68,共8页
BACKGROUND Reactivation of hepatitis B virus(HBV)infection is a well-known risk that can occur spontaneously or following immunosuppressive therapies,including cancer chemotherapy.HBV reactivation can cause significan... BACKGROUND Reactivation of hepatitis B virus(HBV)infection is a well-known risk that can occur spontaneously or following immunosuppressive therapies,including cancer chemotherapy.HBV reactivation can cause significant morbidity and even mortality,which are preventable if at-risk individuals are identified through screening and started on antiviral prophylaxis.AIM To determine the prevalence of chronic HBV(CHB)and occult HBV infection(OBI)among oncology and hematology-oncology patients undergoing chemo-therapy.METHODS In this observational study,the prevalence of CHB and OBI was assessed among patients receiving chemotherapy.Serological markers of HBV infection[hepatitis B surface antigen(HBsAg)/anti-hepatitis B core antigen(HBc)]were evaluated for all patients.HBV DNA levels were assessed in those who tested negative for HBsAg but positive for total anti-HBc.RESULTS The prevalence of CHB in the study cohort was determined to be 2.3%[95%confidence interval(95%CI):1.0-4.2].Additionally,the prevalence of OBI among the study participants was found to be 0.8%(95%CI:0.2-2.3).CONCLUSION The findings of this study highlight the importance of screening for hepatitis B infection in oncology and hematology-oncology patients undergoing chemotherapy.Identifying individuals with CHB and OBI is crucial for implementing appropriate antiviral prophylaxis to prevent the reactivation of HBV infection,which can lead to increased morbidity and mortality. 展开更多
关键词 Hepatitis B virus Chronic hepatitis B Occult B infection ONCOLOGY Hepatitis B reactivation Hematologyoncology
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急性区域性隐匿性外层视网膜病变误诊为视神经视网膜病变1例
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作者 许畅 毛晓春 《临床眼科杂志》 2016年第3期214-214,共1页
急性区域性隐匿性外层视网膜病变(acute zonal occult outer retinopathy,AZOOR)是一组急性发作、眼底表现不明显,以单个或多个区域视网膜外层功能障碍为特征的症候群。其早期可仅表现为视力下降,传统的检测手段,如眼底彩色照相、视... 急性区域性隐匿性外层视网膜病变(acute zonal occult outer retinopathy,AZOOR)是一组急性发作、眼底表现不明显,以单个或多个区域视网膜外层功能障碍为特征的症候群。其早期可仅表现为视力下降,传统的检测手段,如眼底彩色照相、视野、视网膜电图及荧光素眼底血管造影(FFA)等在AZOOR的诊断及随访中均存在一定的局限性易误诊、漏诊。 展开更多
关键词 视网膜病变 视网膜电图 隐匿性 OCCULT 视野检查 黄斑中心凹反光 光感受器细胞层 性易 ZONAL 眼底照相
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The "Metaphysical Physician" in Victorian Fiction: The Moonstone and A Romance of Two Worlds
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作者 Pfitha Kundu 《Journal of Literature and Art Studies》 2016年第1期43-48,共6页
The Victorian period experienced, among many other paradoxes, an ongoing tension between science and spirituality. Bearing the legacy of the "Enlightenment Rationalism" and the Cartesian division between "matter" ... The Victorian period experienced, among many other paradoxes, an ongoing tension between science and spirituality. Bearing the legacy of the "Enlightenment Rationalism" and the Cartesian division between "matter" and "mind" since the eighteenth century, the Victorian minds had to deal with a contemporary world rapidly unfolding new discoveries in geology, astronomy, biology, and medical sciences. However, these could not completely erase the spiritual belief from the human mind. Rather they sought to reshape their codes in terms of "alternative sciences" like occultism and metaphysical psychiatry (pre-Freudian). This paper seeks to explore the characterisation of the "metaphysical" physician in two novels by Wilkie Collins and Marie Corelli, showing how these figures play a crucial role in negotiating the tensions between science and spiritualism. 展开更多
关键词 occultism alternative science metaphysical physician
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An overview of occult hepatitis B virus infection 被引量:22
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作者 Zeinab Nabil Ahmed Said 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第15期1927-1938,共12页
Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replic... Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome. 展开更多
关键词 Hepatitis B virus Occult infection Occult hepatitis B virus infection Occult hepatitis B Chronic liver disease Hepatocellular carcinoma Hepatitis B surface antigen
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Persistent occult hepatitis B virus infection:Experimental findings and clinical implications 被引量:17
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作者 Patricia M Mulrooney-Cousins Tomasz I Michalak 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第43期5682-5686,共5页
Hepatitis B virus (HBV) is a highly pathogenic virus that causes chronic liver diseases in millions of people globally. In addition to a symptomatic, serologically evident infection, occult persistent HBV carriage has... Hepatitis B virus (HBV) is a highly pathogenic virus that causes chronic liver diseases in millions of people globally. In addition to a symptomatic, serologically evident infection, occult persistent HBV carriage has been identified since nucleic acid amplification assays of enhanced sensitivity became introduced for detection of hepadnaviral genomes and their replicative intermediates. Current evidence indicates that occult HBV infection is a common and long-term consequence of resolution of acute hepatitis B. This form of residual infection is termed as secondary occult infection (SOI). The data from the woodchuck model of HBV infection indicate that exposure to small amounts of hepadnavirus can also cause primary occult infection (POI) where virus genome, but no serological makers of exposure to virus, are detectable, and the liver may not be involved. However, virus replicates at low levels in the lymphatic system in both these forms. We briefly summarize the current understanding of the nature and characteristics of occult hepadnaviral persistence as well as of its documented and expected pathological consequences. 展开更多
关键词 Hepatitis B viWoodchuck hepatitis virus Hepadnaviruses Hepadnaviral hepatitis Occult viral persistence Hepadnavirus lymphotropism Primary occult infection Secondary occult infection Virus reactivation
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Colorectal cancer screening: An updated review of the available options 被引量:57
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作者 Iyad A Issa Malak Noureddine 《World Journal of Gastroenterology》 SCIE CAS 2017年第28期5086-5096,共11页
Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. N... Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including “westernized” diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon<sup>®</sup>) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program. 展开更多
关键词 Colorectal cancer COLONOSCOPY Occult blood Fecal DNA test Blood DNA test Screening GUIDELINES
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Performance value of high risk factors in colorectal cancer screening in China 被引量:45
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作者 Wen Meng Shan-Rong Cai +3 位作者 Lun Zhou Qi Dong Shu Zheng Su-Zhan Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第48期6111-6116,共6页
AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) an... AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation.Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy.RESULTS:The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia.The iFOBT had the highest sensitivity,lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas.A history of chronic cholecystitis or cholecystectomy,chronic appendicitis or appendectomy,and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas.The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for nonadenomatous polyps.A history of chronic appendicitis or appendectomy,chronic constipation,chronic diarrhea,mucous and bloody stool,CRC in first degree relatives,malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps.Except for a history of malignant tumor in screening for non-adenomatous polyps,the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality.CONCLUSION:The iFOBT may be the best marker for screening for advanced neoplasias and adenomas.Some unique high risk factors may play an important role in CRC screening in China. 展开更多
关键词 Colorectal cancer Cancer screening FECES Occult blood Risk factors Predictive value of tests
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Pathogenesis of occult chronic hepatitis B virus infection 被引量:12
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作者 Rocio Aller de la Fuente María L Gutiérrez +3 位作者 Javier Garcia-Samaniego Conrado Fernández-Rodriguez Jose Luis Lledó Gregorio Castellano 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第12期1543-1548,共6页
Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occul... Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays;but more frequently it is due to a strong suppression of viral replication and gene expression.OBI is an entity with world-wide diffusion.The failure to detect HBsAg,despite the persistence of the viral DNA,is due in most cases to the strong suppression of viral replication and gene expression that characterizes this"occult"HBV infection;although the mechanisms responsible for suppression of HBV are not well understood.The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection.Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma. 展开更多
关键词 Occult hepatitis B virus infection Hepatitis B virus-DNA Anti-HBc alone Hepatitis B virus Hepadnaviral hepatitis Occult viral persistence Primary occult infection Secondary occult infection Virus reactivation
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Occult sporadic insulinoma: Localization and surgical strategy 被引量:21
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作者 Bassam Abboud Joe Boujaoude 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第5期657-665,共9页
Insulinomas continue to pose a diagnostic challenge to physicians, surgeons and radiologists alike. Most are intrapancreatic, benign and solitary. Biochemical diagnosis is obtained and imaging techniques to localize l... Insulinomas continue to pose a diagnostic challenge to physicians, surgeons and radiologists alike. Most are intrapancreatic, benign and solitary. Biochemical diagnosis is obtained and imaging techniques to localize lesions continue to evolve. Surgical resection is the treatment of choice. Despite all efforts, an occult insulinoma (occult insulinoma refers to a biochemically proven tumor with indeterminate anatomical site before operation) may still be encountered. New localization preoperative techniques decreases occult cases and the knowledge of the site of the mass before surgery allows to determine whether enucleation of the tumor or pancreatic resection is likely to be required and whether the tumor is amenable to removal via a laparoscopic approach. In absence of preoperative localization and intraoperative detection of an insulinoma, blind pancreatic resection is not recommended. 展开更多
关键词 INSULINOMA OCCULT CT scan Endoscopic ultrasonography SURGERY LAPAROSCOPY
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