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71.
Infection or immunization with measles virus induces a protective immune reaction including neutralizing antibodies against the haemagglutinin and fusion protein. The reactivity of the polyclonal IgG response of sera obtained from late convalescent donors was studied, using overlapping 15mer peptides covering the complete sequence of the measles virus haemagglutinin. Most sera reacted with a similar set of peptides generating a characteristic binding pattern. The reactive peptides correspond to a region mediating cell hemolysis (aa310–325), to regions which serve as targets to neutralizing antibodies and to a putative transmembrane region (aa35–58). The latter region contains also a human T-cell epitope providing evidence of a non-random association of T- and B-cell epitopes. We also immunized different strains of mice and rabbits with measles virus. In contrast to the human sera, animal sera with strong neutralizing activities did not react with any of the H-protein peptides. The mostly weak reactivities with the linear sequences contrast with the strong neutralizing activities of the human or animal antibodies, suggesting that these primarily recognize the fusion protein or conformational epitopes of the haemagglutinin protein.  相似文献   
72.
背景 随着人口老龄化进程的加快,同时患有多种慢病已成为老年人的常态,老年多重慢病相关研究也不断丰富,但鲜有对其研究进展及热点进行分析。目的 分析国内外老年多重慢病的研究热点,揭示近十年来(2010—2021年)老年多重慢病领域研究前沿的热点主题,为相关研究者追踪前沿信息提供参考。方法 基于文本挖掘技术和文献计量学等方法,检索Web of Science核心合集、Scopus、中国知网、万方数据知识服务平台、维普网、PubMed、中华医学会期刊全文数据库、APA-PsycINFO美国心理学会数据库中老年多重慢病领域的相关文献,检索时间为2010—2021年。使用CiteSpace 6.1.3、PASW 18、BICOMB 2.04等软件对文献的发文量趋势、来源、作者、机构、关键词等方面进行分析及可视化,并绘制战略坐标图对领域研究热点进行分析。结果 最终纳入老年多重慢病相关文献9 392篇,其中外文文献5 776篇,中文文献3 616篇。2010—2021年老年多重慢病领域中外文献发文量均呈指数型增长,中文文献年增长率为13.27%,外文文献年增长率为15.84%,该领域正处于发展阶段。中...  相似文献   
73.
目的: 建立一种利用太赫兹时域光谱和多种化学计量学方法鉴别龟甲真伪的新方法。方法: 选用正品乌龟和伪品红耳彩龟的腹甲进行实验,先用经典的性状鉴别、显微鉴别方法比较两种样品的典型性状特征,后利用太赫兹时域光谱仪测得样品的光谱信息,对样品谱图进行平滑处理和基线校准,并运用化学计量方法进行数据分析以区分正品和伪品龟甲。结果: 性状鉴别结果显示完整正、伪品龟甲样品仅有细微差异,且其碎片或粉末基本无差异;显微鉴别未在两种样品中发现明显的特征差异性结构;两种样品的太赫兹时域光谱曲线图经快速傅里叶变换滤波器平滑滤波处理、正交偏最小二乘法判别分析处理后呈现显著差异。结论: 利用太赫兹时域光谱技术结合正交偏最小二乘法判别分析可以实现龟甲真伪品的精准鉴别。  相似文献   
74.
Summary The renal and hormonal effects of the 1-adrenoceptor blocker bunazosin were examined in 6 patients with essential hypertension. Oral bunazosin for 4 to 12 weeks significantly decreased mean blood pressure by 10%, increased effective renal blood flow and creatinine clearance by 34% and 37%, respectively, the plasma norepinephrine concentration was elevated by 60%, and the plasma atrial natriuretic peptide level was lowered by 22%. The plasma renin activity and aldosterone concentration were unchanged. Thus, a moderate reduction in blood pressure was produced by bunazosin treatment while maintaining renal perfusion.  相似文献   
75.
76.
When intracellular recordings were made from the antral region of murine stomach, cells with three different patterns of electrical activity were detected. One group of cells generated follower potentials, the second group generated pacemaker potentials and the third group generated slow waves that consisted of primary and secondary components. Slow waves recorded in different regions of the gastric antrum had similar amplitudes but different characteristic shapes. At the greater curvature, slow waves had large initial components. Midway between the greater and lesser curvature, the amplitude of the initial component was reduced and at the lesser curvature an initial component was difficult to detect. When the distributions of myenteric (ICC-MY) and intramuscular interstitial cells of Cajal (ICC-IM) were determined, using an antibody to Kit, ICC-MY were found to be present at the greater curvature but were greatly reduced in density at the lesser curvature. In contrast, ICC-IM were found in the circular layer of each region. When recordings were made from the antrum of W/WV mice, which lack ICC-IM, incomplete slow waves were detected and their amplitudes fell from the greater to the lesser curvature. Again, a corresponding fall in the density of ICC-MY was detected. The observations indicate that the contribution of ICC-MY and ICC-IM to the generation of slow waves varies in different regions of the mouse gastric antrum.  相似文献   
77.
An in vitro system was used to study the ability of virulent gonococci to adhere to vaginal epithelial cells obtained from healthy donors during the pre- and postmenstrual phases, and from those in early pregnancy. It was found that more gonococci adhered to the cells from donors in the postmenstrual phase than to cells from those in the premenstrual one. This difference was statistically highly significant. The attachment rate of gonococci to vaginal epithelial cells was similar in early pragnancy and in the premenstrual phase.  相似文献   
78.
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer.  相似文献   
79.
41名肢残者十六项人格特质测验   总被引:1,自引:1,他引:1  
张丹 《中国心理卫生杂志》1989,3(6):248-249,271
应用“卡特尔十六项人格特质测验问卷”,对41名肢残者和40名健全人进行对照研究。结果表明,肢残人较健全人在孤独性上具有明显的差异,偏于缄默,固执,关注外界信息,具有一定的防卫倾向。肢残人富于实验性,较健全人更自由、激进、好学,具有较强的独立工作能力,希望生活更充实多彩。在各项能力水平上,肢残上与健全人没有显著差别。不同性别肢残人人格特质在敏感性上差异明显,女性较理智和着重现实,而男性则偏于敏感,易感情用事。  相似文献   
80.
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