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91.
Summary A formula relating oncotic pressure torat serum protein concentration was derived and found to be in complete agreement with the Landis-Pappenheimer formula derived from measurements onhuman plasma.This study was supported by the Danish Medical Research Council and Johan and Hanne Weimann's legacy.  相似文献   
92.
Sixteen Borrelia burgdorferi strains, including all three species, were compared in a colorimetric bactericidal assay for their ability to escape the complement-dependent bacteriolysis on incubation in normal human serum free of specific antibodies (NHS). The species B. afzelii was found to be serum resistant (EB1, EB3, FEM1, FEM2, Pko), whereas strains of the species B. garinii were found to be serum sensitive (1/B29, G1, G2, PSth, PBr, PTrob). Six strains, mainly B. burgdorferi sensu stricto, were only partially sensitive (Z25, 297, B31, PKa-I, PBi). All strains activated the complement cascade in NHS, whereas only four strains (G1, G2, PBr, PSth) could activate complement in the presence of EGTA-Mg. After complement activation, covalently bound C3 fragments (C3b, iC3b) were detected on serum-sensitive as well as serum-resistant borrelial strains. Heterogeneity, however, was observed between serum-resistant and serum-sensitive strains with respect to deposition of C6 and C9. Whereas serum-sensitive strains were strongly positive for C6 and C9 and were, therefore, killed by the terminal complement complex (TCC), serum-resistant strains were devoid of C6 and C9 on their cell surface. The serum resistance may, therefore, be due to an absent or only transient formation of TCC on the bacterial surface. Received: 17 September 1996  相似文献   
93.
血脂测定结果的临床可接受性分析   总被引:3,自引:2,他引:3  
目的:通过对不同检测系统血脂测定结果的偏倚评估,分析各系统间结果的可比性和临床可接受性。方法:参照CLSI文件相关要求,以可溯源的检测系统为目标检测系统,测定总胆固醇(TCH)、甘油三酯(TG)、载脂蛋白A1(APOA1)、载脂蛋白B(APOB)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C),对本院3个不同检测系统进行朗道质控物(水平2和水平3)各测定21次和测定新鲜血清标本40份。结果:朗道质控物和新鲜血清标本TCH、TG、APOA1、APOB、HDL-C、LDL-C浓度在系统间的差异均有显著性(P<0.05)。除LDL-C在各检测系统间的相关系数为0.7859~0.9259之间外,其他项目各系统间的相关系数均大于0.975。各检测系统测定TCH、TG的不精密度CV均小于5%,其他项目的不精密度CV均小于10%;以可溯源检测系统1为目标检测系统,临床可接受性能评价:TCH、LDL-C在检测系统2和检测系统3超出临床接受范围,HDL-C在检测系统2超出临床接受范围,其他项目临床均可接受。结论:3个不同检测系统测定TG、APOA1、APOB结果具有可比性;测定HDL-C结果具有部分可比性,TCH、LDL-C结果不具有可比性,需采取整改措施。  相似文献   
94.
目的 检测血清淀粉样P成分(SAP)与不同DNA的结合活性并研究SAP与DNA的结合是否有利于此类抗原的清除,探讨它在SLE发生发展中的作用及意义。方法 用亲和层析和凝胶过滤方法自小鼠和人血清中纯化SAP,分别提取来自细菌、质粒、酵母、小鼠淋巴细胞等不同DNA,用DOT-EIA方法检测SAP与它们的结合活性,用巨噬细胞吞噬实验观察SAP与DNA结合后对DNA清除的影响。结果 人和小鼠SAP均与细菌DNA结合最强,其次为质粒、酵母DNA,与淋巴细胞DNA和小牛胸腺DNA的结合较弱,与单链λDNA结合最弱;与来源于活化状态小鼠淋巴细胞DNA的结合力高于非活化状态;SAP与活化淋巴细胞DNA结合后可促进巨噬细胞对DNA的吞噬。结论 SAP与不同DNA结合活性各异。  相似文献   
95.
96.
分泌性中耳炎中耳积液和血清中sIL-2R水平的初步研究   总被引:2,自引:0,他引:2  
应用酶联免疫吸附法(ELISA)对30例正常人血清(对照组)和60例分泌性中耳炎患者(SOM组)中耳积液和血清中可溶性白细胞介素2受体(sIL-2R)进行了检测。结果示SOM组血清sIL-2R水平明显高于对照组,MEF中其含量明显高于血清;鼻咽癌组血清及MEF中sIL-2R水平明显高于─般SOM组;粘液组高浆液组;慢性组高于急性组(均P<0.01)。提示:血清及MEF中sIL-2R水平的测定有助于对SOM患者免疫状态的评估;MEF中sIL-2R可能主要由局部中耳粘膜产生;MEP中高浓度的sIL-2R存在可能是SOM迁延不愈的─个原因。  相似文献   
97.
Summary Serum digoxin concentration and half-life were radioimmunologically determined in 9 mature newborns after 7 days medication with digoxin. The newborns were in respiratory distress treated with continuous positive airway pressure or were suspected to have serious congenital heart disease. Loading dose was 26 µg/kg body weight intravenously and 35 µg/kg body weight orally, respectively. Maintenance dose corresponded to 1/8th of the digitalization dose twice daily.The serum digoxin level 12 h after the last dose varied between 1.4 and 2.5 ng/ml (mean 2.0 ng/ml, Sx=0.4). The serum half-life of digoxin varied between 21.7 and 42.4 h (mean 30.0 h, Sx=7.7). The mean serum half-life of digoxin of 30 h attained values found in adults without renal disease. This suggests that the serum digoxin levels of newborns which are usually higher if compared with those of adults result from higher digoxin doses per unit body weight and not from diminished digoxin elimination.  相似文献   
98.
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla ) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla (18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla may have favourable effects on overall physical fitness and some serum lipid variables in older individuals.  相似文献   
99.
The effects of hyperfiltration induced due to unilateral nephrectomy on immunologically induced glomerular injuries were studied. Glomerulonephritis was induced in rats by sensitizing them with egg albumin as an antigen. Unilateral nephrectomy did not affect the removal rate of the antigen from the glomeruli in the rats, but accelerated the rate of the glomerular injuries after cessation of the immunologically induced glomerular inflammation. The histopathological features were characterized by sciero-adhesive lesions with aneurysmal dilatation and hyalinosis of the glomerular capillaries. The parietal epithelial cells extended from the Bowman's capsule with matrices to cover the denuded basement membrane and formed adhesions. The neighboring capillaries collapsed, and the sclero-adhesive lesions progressed. These findings indicate that hyperfiltration at the capillary level did not accelerate the recovery from glomerulonephritis, but induced glomerular sclerosis with adhesions and deteriorated the trivial glomerular injuries to produce similar focal segmental lesions.  相似文献   
100.
本对100例健康胎儿脐带血血清中六种微量元素(锌,铁,铜,钙,镁,锰)含量进行了测定,结果提示,所测的六种元素含量在男,田性胎儿之间似无明显差异(P>0.05),与成人比较,胎儿的锌,铁,锰含量高于成人,铜,钙含量低于成人,镁含量与成人相近。  相似文献   
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