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31.
张新民  米贤洋  唐蜜 《疑难病杂志》2004,3(3):135-136,F003
目的 了解支气管扩张症肺组织降钙素 (CT)蛋白表达水平与其病变特点的关系。方法 应用免疫组化方法定量分析 4 5例支气管扩张症患者手术切除的肺组织 ,对其气道上皮内神经内分泌细胞 (NEC)计数 ,并与 19例无肺部疾患的尸检肺组织进行比较。结果  2组均可见被染成棕红色的CT阳性细胞 ,它们分布于肺内各级支气管上皮细胞间 ,以支气管分叉处较多见。支气管扩张症组肺组织内5 0 0 0个上皮细胞中CT阳性细胞数为 (6 7.4 8± 11.0 3)个 ,非支气管扩张症组肺组织内CT阳性细胞数仅为 (5 .0 2± 1.0 0 )个 ,2组比较有非常显著性差异 (P <0 .0 0 1)。结论 支气管扩张症肺组织高水平CT表达可能与其慢性炎症改变有关 ,其局部CT表达增高可能系机体对支气管扩张病变的一种局部性代偿或调节机制。  相似文献   
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Radioactive tracer techniques using 131I- and 125I-insulin have been applied to study insulin metabolism. A simple method to label human insulin with 123I to a high specific activity is described. We have used this radiotracer to study insulin kinetics in vivo in normal subjects and in two groups of diabetic patients. The rate of decline in plasma radioactivity was shown to be significantly reduced in patients with diabetes. There were no significant differences in the time-activity profiles of liver and kidneys between the groups studied. This technique may provide insight into the mechanism of some forms of insulin resistance.  相似文献   
34.
Oligoclonal immunoglobulins in HIV infection   总被引:1,自引:0,他引:1  
We tested 150 patients infected with human immunodeficiency virus (HIV) for the presence of oligoclonal bands in serum, prompted by reports that these abnormal proteins may have prognostic significance. Sixty HIV-negative individuals from "at-risk" groups were tested along with 80 HIV-negative, healthy blood donors for the presence of these bands. All sera were tested by isoelectric focusing, because it is more sensitive for this purpose than more-conventional electrophoretic techniques. In the HIV-positive group, 61% of the sera had oligoclonal bands; in the HIV-negative "at-risk" group, 36% had bands. No bands were detectable in sera from the healthy blood-donor group. Some patients were also followed for differing periods throughout their infection, and changes in their oligoclonal banding patterns could not be correlated with disease progression. The fact that oligoclonal bands were found to be present without HIV infection in a substantial number of individuals from within the "at-risk" groups leads us to conclude that the presence of oligoclonal bands in HIV infection is of limited prognostic significance.  相似文献   
35.
Treatment effects of the Herbst appliance   总被引:2,自引:0,他引:2  
The purpose of this study was to examine the results of treatment with a modified Herbst appliance. The pretreatment and posttreatment cephalometric and dental cast records of 32 consecutively treated Class II, Division 1 cases were evaluated. Results showed that the skeletal Class II correction was achieved by an average 1.5 mm of greater than normal forward mandibular growth in conjunction with a minimal "headgear" effect inhibiting maxillary growth. Dental Class II correction was achieved by significant amounts of distal bodily movement and tipping of the maxillary first molars combined with bodily forward movement of the mandibular first molars. Significant increases were seen in maxillary arch length and maxillary intercanine and intermolar widths, while the mandibular arch demonstrated few changes. Slight forward movement of the mandibular incisors was noted with no significant change occurring in the maxillary incisors.  相似文献   
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The ability of F(ab′)2 antibody preparations to suppress an immune response is much less than that of intact 7S antibody. The activity possessed by F(ab′)2 preparations withstood repurification procedures, hence contamination with intact 7S antibody is unlikely. Daily or thrice daily injections of antibody did not make equal the suppressive activities of F(ab′)2 and intact antibody, indicating that rapid excretion of F(ab′)2 antibody is not the sole factor involved in the difference in immunosuppressive potency between intact 7S and F(ab′)2 antibody. Some possibilities for distinct differences in the mechanism of the immuno-suppressive action of F(ab′)2 and 7S antibodies are raised and discussed.  相似文献   
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Summary Six monoclonal antibodies directed against EHV-1 glycoprotein 13 were characterized. Five antibodies neutralized EHV-1 and were directed against a single antigenic site which comprised type-specific and type cross-reactive epitopes. Inhibition of monoclonal antibody binding to this site by post-infection equine sera suggests that it is a target of host antibody during natural infection with either EHV-1 or EHV-4.  相似文献   
40.
目的研究1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者CYP17A1基因突变特点,并结合患者的临床表现与基因突变类型初步探讨P450C17酶蛋白的结构与功能的关系。方法收集1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者的临床资料及其亲属血标本,提取基因组DNA,设计7对引物扩增CYP17A1基因的8个外显子及外显子与内含子的连接区域,琼脂糖凝胶电泳鉴定PCR产物,产物胶回收后直接做为DNA双链模板测序。DNA双链模板不一致的PCR产物经克隆后测序。测序结果在核苷酸序列数据库进行比较分析。结果患者CYP17A1基因突变检测结果为5994-5995delAT/7541C>T复合杂合子。这两种突变均未见报道。推测5994-5995delAT导致I259H,274X,突变形成的截短蛋白质缺少血红素结合区域,因此是没有功能的;而通过人类P450C17酶计算机模型分析显示7541C>T导致的A398V远离酶的活性中心,推测突变可能使酶的活性减弱,而不是完全地丧失。患者临床表现为有自发不规则月经及轻度高血压、低血钾,结合激素测定结果提示肾上腺和性腺保留部分功能。因而患者的基因型与其临床表型是一致的。结论应进行突变P450C17酶的功能学研究来进一步明确结构改变对功能的影响。  相似文献   
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