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成年和老年小鼠脑蛋白质组双向电泳图谱比较 被引量:19
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作者 丁勤学 阙海萍 +2 位作者 郭尧君 景书谦 刘少君 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2001年第5期683-687,共5页
使用双向电泳 (2 DE)比较成年和老年小鼠脑蛋白质差异 ,从分子水平初步探索老年脑蛋白整体变化规律 .以固相 pH梯度等电聚焦为第一向 ,SDS 聚丙烯酰胺凝胶水平电泳 (PAGE)为第二向进行 2 DE .图象分析软件Imagemaster 2DElite分析电... 使用双向电泳 (2 DE)比较成年和老年小鼠脑蛋白质差异 ,从分子水平初步探索老年脑蛋白整体变化规律 .以固相 pH梯度等电聚焦为第一向 ,SDS 聚丙烯酰胺凝胶水平电泳 (PAGE)为第二向进行 2 DE .图象分析软件Imagemaster 2DElite分析电泳图谱 .重复性实验结果显示 ,同组样品在三次不同实验中所得蛋白质斑点数目的相对标准差 (变异系数 )为 4 43%± 0 2 5 % ;同一蛋白质斑点在三次实验中等电点、分子质量和蛋白质量的相对标准差分别为 8 76 %± 5 14% ,13 0 0 %± 4 2 2 %和 10 84%± 9 16 % .成年和老年小鼠脑组织 2 DE图谱分别获得 996和 12 5 6个蛋白质斑点 ,其中 8个蛋白质在老年脑组织中含量降低 ,2 0个蛋白质斑点含量增加 .另至少有 4个蛋白质斑点在老年脑组织中缺失 ,14个蛋白质点为老年脑特有 . 展开更多
关键词 老年 脑蛋白 固相PH梯度 双向电泳图谱 蛋白质组 成年 小鼠 脑老化 功能退变
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Image J软件不同阈值处理模式在多裂肌脂肪浸润程度定量评估中的应用价值
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作者 陈灿 张承旻 +4 位作者 喻学科 陈春华 李凯 赵骏 罗飞 《广西医学》 CAS 2023年第1期34-38,共5页
目的探讨Image J软件不同阈值处理模式在多裂肌脂肪浸润程度定量评估中的应用价值。方法选取40例中老年人作为研究对象,均进行MRI常规序列及磁共振波谱(MRS)序列扫描检查。由2名脊柱外科医生借助Image J软件的不同阈值处理模式测量L4~5... 目的探讨Image J软件不同阈值处理模式在多裂肌脂肪浸润程度定量评估中的应用价值。方法选取40例中老年人作为研究对象,均进行MRI常规序列及磁共振波谱(MRS)序列扫描检查。由2名脊柱外科医生借助Image J软件的不同阈值处理模式测量L4~5椎间盘中心层面多裂肌脂肪浸润程度,1周后重复测量。采用组内相关系数(ICC)评估两名观察者之间及同一观察者不同时间的测量结果的可重复性。以MRS序列测量结果作为定量评估多裂肌脂肪浸润程度的“金标准”。分析Image J软件不同阈值处理模式所测得的多裂肌脂肪浸润程度与MRS序列所测结果的相关性。结果两名观察者之间及同一观察者不同时间测量的多裂肌脂肪浸润程度的可重复性均较高(均ICC>0.8)。Image J软件的固定阈值(60~140)模式、自动阈值模式、人工阈值模式测量的多裂肌脂肪浸润程度与MRS序列测量的多裂肌脂肪浸润程度均呈正相关(均P<0.05),其中采用固定阈值模式(阈值设置为80)时,Image J软件测量的多裂肌脂肪浸润程度与MRS序列测量的结果相关性最高。结论Image J软件不同阈值处理模式测量多裂肌脂肪浸润程度的可重复性高,采用固定阈值处理模式(阈值设置为80)在MRI常规序列上测量可替代MRS序列测量,作为评估多裂肌脂肪浸润程度的有效方法。 展开更多
关键词 多裂肌 脂肪浸润程度 Image J软件 阈值 功能退变
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双下肢胫前浮肿病因的探讨
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作者 杨刚 《中外医疗》 2012年第34期24-25,共2页
胫前水肿是临床常见的体征,但并非所有胫前水肿都是由心、肝、肾、低蛋白或黏液性水肿所致。老龄化生理退变致胫前局部水肿或因药物影响所致的胫前水肿是值得探讨研究的一个课题。现实生活中,临床上会遇到这类患者,病因剖析后如何治疗... 胫前水肿是临床常见的体征,但并非所有胫前水肿都是由心、肝、肾、低蛋白或黏液性水肿所致。老龄化生理退变致胫前局部水肿或因药物影响所致的胫前水肿是值得探讨研究的一个课题。现实生活中,临床上会遇到这类患者,病因剖析后如何治疗这类患者,有待将来进一步的研究及探讨。比如非药物所致的胫前浮肿和药物所致的胫前浮肿。其治疗的方案肯定不同,有的学者认为中医中药是治疗本症的最佳方案,有的则认为中草药能解决,西医西药液能解决。 展开更多
关键词 胫前局部水肿 毛细血管舒缩功能退变 双下肢远端与心脏水平面垂直距离
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Using the response-effect trait framework to disentangle the effects of environmental change on the ecosystem services 被引量:1
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作者 Cheng Zheng Fei Zhang +7 位作者 Ziqi Lin Liuhuan Yuan Hongbin Yao Gaohui Duan Yandan Liu Yangyang Liu Haijing Shi Zhongming Wen 《Journal of Plant Ecology》 SCIE CSCD 2024年第5期78-90,共13页
Functional traits play a vital role in mediating the responses of ecosystem services to environmental changes and in predicting the functioning of the ecosystem.However,the connection between functional traits and eco... Functional traits play a vital role in mediating the responses of ecosystem services to environmental changes and in predicting the functioning of the ecosystem.However,the connection between functional traits and ecosystem services has become increasingly intricate due to climate change and human activities for degraded ecosystems.To investigate this relationship,we selected 27 sampling sites in the Yanhe River Basin of the Chinese Loess Plateau,each containing two types of vegetation ecosystems:natural vegetation and artificial vegetation ecosystems.At each sampling site,we measured ecosystem services and calculated the composition index of community traits.We established a response–effect trait framework that included environmental factors such as climate,elevation and human activities.Our results showed that leaf tissue density(LTD)was the overlapping response and effect trait when responding to climate change.LTD is positively correlated with mean annual temperature and negatively correlated with supporting services.Under the influence of human activities,leaf nitrogen content and leaf dry matter content were carriers of environmental change.Comparing the two vegetation ecosystems,the relationship between functional traits and ecosystem services showed divergent patterns,indicating that human activities increased the uncertainty of the relationship between functional traits and ecosystem services.Trait-based ecology holds promise for enhancing predictions of ecosystem services responses to environmental changes.However,the predictive ability is influenced by the complexity of environmental changes.In conclusion,our study highlights the importance of understanding the complex connection between functional traits and ecosystem services in response to climate changes and human activities. 展开更多
关键词 Robinia pseudoacacia plantation BEF degraded ecosystem climate change functional diversity linear mixed-effect models
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Heart rate variability and its response to thyroxine replacement therapy in patients with hypothyroidism
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作者 邢惠莉 沈迎 +2 位作者 陈寒蓓 王一尘 沈卫峰 《Chinese Medical Journal》 SCIE CAS CSCD 2001年第9期10-12,102,共4页
Objective To analyze heart rate variability (HRV)and its changes with thyroxine treatment in patients with hypothyroidism. Methods HRV was analyzed using 24-hour electrocardiographic recording in 38 patients with hy... Objective To analyze heart rate variability (HRV)and its changes with thyroxine treatment in patients with hypothyroidism. Methods HRV was analyzed using 24-hour electrocardiographic recording in 38 patients with hypothyroidism and 21 normal controls. The changes in HRV were evaluated for the 18 hypothyroid patients after 3 months of thyroxine therapy.Results The time domain measurements of HRV in hypothyroid patients were much lower than those in the control group. As to HRV frequency domain, the high frequency power was significantly higher, but the ratio of low frequency power to frequency power for hypothyroid patients was lower than in the controls. These abnormal changes of HRV measurements in hypothyroid patients were improved after treatment with thyroxine and were associated with recovery of serum concentrations of FT3 and FT4. Conclusions Patients with hypothyroidism often have autonomic neuropathies with a higher level of vagal tone. These abnormalities could be partly improved by thyoxine therapy. 展开更多
关键词 heart rate variability · hypothyroidism · autonomic nerve function
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Fusion Energy and Stopping Power in a Degenerate DT Pellet Driven by a Laser-Accelerated Proton Beam
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作者 M.Mehrangiz A.Ghasemizad +1 位作者 S.Jafari B.Khanbabaei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第6期761-766,共6页
In this paper, we have improved the fast ignition scheme in order to have more authority needed for highenergy-gain. Due to the more penetrability and energy deposition of the particle beams in fusion targets, we empl... In this paper, we have improved the fast ignition scheme in order to have more authority needed for highenergy-gain. Due to the more penetrability and energy deposition of the particle beams in fusion targets, we employ a laser-to-ion converter foil as a scheme for generating energetic ion beams to ignite the fusion fuel. We find the favorable intensity and wavelength of incident laser by evaluating the laser-proton conversion gain. By calculating the source-target distance, proton beam power and energy are estimated. Our analysis is generalized to the plasma degeneracy effects which can increase the fusion gain several orders of magnitude by decreasing the ion-electron collisions in the plasma.It is found that the wavelength of 0.53 μm and the intensity of about 1020W/cm^2, by saving about 10% conversion coefficient, are the suitable measured values for converting a laser into protons. Besides, stopping power and fusion burn calculations have been done in degenerate and non-degenerate plasma mediums. The results indicate that in the presence of degeneracy, the rate of fusion enhances. 展开更多
关键词 proton fast ignition degenerate plasma laser-to-proton converter foil stopping power
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