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51.
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
52.
S. Breitner-Ruddock Reinhard Würzner Jörg Schulze V. Brade 《Medical microbiology and immunology》1997,185(4):253-260
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
53.
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
54.
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
55.
D. Lang G. G. Belz R. Hofstetter U. Töllner G. von Bernuth 《Journal of molecular medicine (Berlin, Germany)》1976,54(8):389-390
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
56.
Nobuo Takeshima Kiyoji Tanaka Fumio Kobayashi Takemasa Watanabe Takashi Kato 《European journal of applied physiology》1993,67(2):138-143
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
57.
Koh Nakazawa 《Pathology international》1990,40(9):643-654
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
58.
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
59.
The aim of this study was to determine the blood protein changes during different stages of pregnancy and to compare with prepregnancy diestrus in ewes. A total of 90 blood samples were taken from ten Makuii ewes (the native sheep breed in Iran) at diestrus and on days 8, 14, 28, 45, 60, 90, 125, and 145 of pregnancy. Serum protein electrophoresis of samples exhibited four fractions: albumin, α, β, and γ fractions in Makuii ewes, which in α- and γ-globulin bands were divided to α1 and α2; and γ1 and γ2, respectively. The mean concentrations (in gram per deciliter) of total serum proteins, albumin, α1-, α2-, β-, γ1-, and γ2-globulin at diestrus period were 7.03, 3.77, 0.18, 0.74, 0.41, 1.56, and 0.41, respectively. Those values fluctuated nonsignificantly throughout gestation until the 125th day of pregnancy. Thereafter, a significant decrease (p < 0.01) in serum protein levels occurred at the 145th day of pregnancy compared to prepregnancy and other gestational time points. It was concluded that blood protein levels declined sharply during late gestation when the nutrient demands of the fetus were maximal. 相似文献
60.
Serum hormones in male strength athletes during intensive short term strength training 总被引:1,自引:0,他引:1
Summary Training-induced adaptations in the endocrine system and strength development were investigated in nine male strength athletes during two separate 3-week intensive strength training periods. The overall amount of training in the periods was maintained at the same level. In both cases the training in the first 2 weeks was very intensive: this was followed by a 3rd week when the overall amount of training was greatly decreased. The two training periods differed only in that training period I included one daily session, while during the first 2 weeks of period II the same amount of training was divided between two daily sessions. In general, only slight and statistically insignificant changes occurred during training period I in mean concentrations of serum hormones examined or sex hormone-binding globulin as well as in maximal isometric leg extensor force. However, during training period II after 2 weeks of intensive strength training a significant decrease (P<0.05) was observed in serum free testosterone concentration [from 98.4 (SD 24.5) to 83.8 (SD 14.7) pmol · l–1] during the subsequent week of reduced training. No change in the concentration of total testosterone was observed. This training phase was also accompanied by significant increases (P<0.05) in serum luteinizing hormone (LH) and cortisol concentrations. After 2 successive days of rest serum free testosterone and LH returned to (P<0.05) their basal concentrations. Training period II led also to a significant increase (P<0.05) [from 3942 (SD 767) to 4151 (SD 926) N] in maximal force. These findings suggest that in male strength athletes dividing the amount of training into smaller units may create more effective training stimuli leading to further strength development. 相似文献