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31.
32.
How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
33.
Impaired expression of the FMR1 gene is responsible for the fragile X mental retardation syndrome. The FMR1 gene encodes a cytoplasmic protein with RNA-binding properties. Its complex alternative splicing leads to several isoforms, whose abundance and specific functions in the cell are not known. We have cloned in expression vectors, cDNAs corresponding to several isoforms. Western blot comparison of the pattern of endogenous FMR1 proteins with these transfected isoforms allowed the tentative identification of the major endogenous isoform as ISO 7 and of a minor band as an isoform lacking exon 14 sequences (ISO 6 or ISO 12), while some other isoforms (ISO 4, ISO 5) were not expressed at detectable levels. Surprisingly, in immunofluorescence studies, the transfected splice variants that exclude exon 14 sequences (and have alternate C-terminal regions) were shown to be nuclear. Such differential localisation was however not seen in subcellular fractionation studies. Analysis of various deletion mutants suggests the presence of a cytoplasmic retention domain encoded in exon 14 and of a nuclear association domain encoded within the first eight exons that appear however to lack a typical nuclear localisation signal.   相似文献   
34.
One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition.  相似文献   
35.
Cui Y  Zhao X  Tang X  Luo Y 《Biomaterials》2004,25(3):451-457
As biodegradable materials, linear polyphosphazenes undergo rapid hydrolysis degradation but exhibit poor mechanical properties. Blending with biodegradable polyesters or inorganic particles strengthen their mechanical properties but give rise to slower degradation rate. To balance the mechanical properties and the degradation rate, micro-crosslinked polyphosphazenes were synthesized in this study. Their glass transition temperatures, mechanical properties, and in vitro degradation behavior were investigated. 2-hydroxyethyl methacrylate (HEMA) was firstly attached to the side chain along with glycine ethyl ester to prepare co-substituted poly(organophosphazene) with pendant ethenyl substituents. The co-substituted poly(organophosphazene) was blended with HEMA or acrylic acid (AA) followed by a free radical polymerization to prepare micro-crosslinked poly(organophosphazenes). The resulting crosslinked polymers showed two separate glass transition temperatures depending on the HEMA or AA feed. Incorporation of crosslinking affected the mechanical properties positively. Crosslinked poly(organophosphazenes) showed an approximately 11-17 fold increase in terms of modulus of elasticity when compared to the linear counterpart. In vitro degradation tests indicated that HEMA-crosslinked polymers hydrolyzed at a retarded rate while AA-crosslinked polymers hydrolyzed at a moderate rate compared to linear polymers.  相似文献   
36.
The C4a anaphylatoxin was purified from rat sera activated by heat-aggregated IgG. The anaphylatoxin was isolated by a three-step purification procedure and was judged to be homogeneous based on visualization of a single stained band after electrophoresis on both cellulose acetate membrane strips and on 9% SDS-polyacrylamide gels. Results from Ouchterlony and radioimmunoassay analysis indicated that neither rat C5A nor C3a contaminated the C4a preparation. Rat C4a is a glycoprotein estimated to be 11,000-12,000 mol. wt and contains 76 amino acid residues representing a mol. wt of 8577 and one oligosaccharide unit of 2000-3000 mol. wt. Rat C4a is weakly active in contracting guinea pig ileum at 0.1-1 microM, which is comparable with the activity of human C4a. Both human and bovine C4a are polypeptides free of carbohydrate while rat and presumably mouse C4a are glycoproteins. The complete primary structure of rat C4a anaphylatoxin has been elucidated as follows: (formula; see text)  相似文献   
37.
人肝癌组织中p53与HSP70相互作用的初步研究   总被引:7,自引:1,他引:7  
目的 :探讨人肝癌中热休克蛋白 70 (HSP70 )与 p5 3的相互作用。方法 :用免疫组织化学染色法 ,从 12例肝癌组织中筛选HSP70与 p5 3均呈阳性表达的标本 ,并以免疫共沉淀法提取之。然后用SDS PAGE及Westernblot分析双阳性标本中两种蛋白的存在形式。结果 :用免疫组织化学法检测到 12例肝癌组织中有 3例为双阳性 ,用抗HSP70mAb免疫共沉淀的样品 ,可检测到 p5 3蛋白。用抗p5 3mAb免疫共沉淀的样品也可检测到HSP70蛋白。结论 :人肝癌中p5 3与HSP70以复合物的形式而存在 ,此可为肝癌的发病机制及免疫治疗的研究提供新的思路  相似文献   
38.
目的 比较周围神经端侧缝合与神经移植的效果。方法 选用体重 2 0 0~ 30 0gWistar大白鼠 ,左侧后肢腓总神经与胫神经端侧缝合 ,右侧腓总神经采用神经移植修复。结果  3个月后运动神经传导速度分别为2 9.6 8± 5 .34m/s、 30 .87± 6 .0m/s(P >0 .0 5 ) ,潜伏期 2 .1± 0 .1ms ,2 .0± 0 .1ms(P >0 .0 5 ) ,波幅 12 .5± 0 .6mV、13.9± 0 .5mV(P >0 .0 5 ) ,组织切片中 ,两组均可见大量神经纤维和髓鞘 ,有髓神经纤维计数分别为 75 7.2± 2 2 .31、775± 2 1.87(P >0 .0 5 )。结论 ①正常神经发出侧芽能通过端侧缝合口长入远端神经 ,使变性神经再神经化 ;②周围神经端侧缝合能取得与神经移植相近的结果。  相似文献   
39.
目的:观察原发性高血压患者红细胞[Ca^2 ]i,多巴胺β羟化酶及ATP含量变化并分析其结果。方法:测定35例高血压患者的红细[Ca^2 ]i、ATP、血清多巴胺β羟化酶活性,血糖及血浆胰岛素含量,并以30例健康成年人为对照。结果:高血压患者的红细胞[Ca^2 ]i、ATP、多巴胺β羟化酶均明显高于对照组(P<0.05,P<0.01),但血糖与胰岛素未见明显变化。结论:高血压患者血清多巴胺β羟化酶活性增强伴随ATP与[Ca^2 ]i升高。  相似文献   
40.
Erectile dysfunction is considered an important health problem that impacts the quality of life of men. Yinyanghuo, also called Epimedium or Horny Goat Weed, is a frequently used Chinese traditional herbal medicine, commonly used in treating erectile dysfunction in China. A network pharmacology method was performed systematically, at a molecular level, to analyse the pharmacological mechanism of Yinyanghuo as erectile dysfunction therapy. The network pharmacology method used in this study primarily includes prescreening of the active compounds, prediction of targets, network analysis and gene enrichment analysis. This network analysis proved that 4 targets (AR, NR3C2, PDE5A and BMP2) could be the targets of Yinyanghuo therapy on erectile dysfunction. Besides, gene enrichment analysis predicted that Yinyanghuo might have a role in erectile dysfunction by regulating 10 molecular functions, 8 cellular components, 10 biological processes and 36 possible targets related to 10 signalling pathways. Our study demonstrated the molecular and pharmacological mechanisms of Yinyanghuo against erectile dysfunction with a holistic approach and demonstrated a powerful method for analysing pharmacological mechanisms and rational utilisation of Traditional Chinese Medicine clinically.  相似文献   
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