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61.
通过兔后肢缺血模型,观察了甘露醇和低温对骨骼肌缺血再灌流损伤的保护作用。结果:甘露醇和低温可以不同程度地降低再灌流后患肢静脉回流血中细胞内酶(CPK、LDH、AST)的活性和脂质过氧化反应终末代谢产物丙二醛(MDA)的含量,减轻骨骼肌细胞超微结构的破坏。两者单独应用效果不明显(P>0.05),联合应用效果非常明显(P<0.01)。提示自由基介导的脂质过氧化反应参与骨骼肌缺血再灌流损伤,甘露醇和低温对其具有协同保护作用。  相似文献   
62.
为探讨药效法估测的效应消除半衰期和效量法估测的表观半衰期对合理制订给药方案的意义和作用,以桂枝汤解热和抗炎的药物动力学实验中所得的相应参数值设计了给药方案,观察了它们在提高药效上的作用。结果表明在给药总剂量相等、首次给药同时开始的情况下,以半衰期设计的给药方案组的药效均明显高于习惯的一次给药组;而以效应消除半衰期设计给药方案组药效增强率又高于以表观半衰期设计的方案组。提示效应消除半衰期比表观半衰期似更有实践意义。  相似文献   
63.
In an experimental study on a piggery it was found that haemolytic Escherichia coli of O-serotypes 138 or 139 proliferated in the intestinal tracts of pigs following weaning, with E. coli of the O-138 type also being occasionally recovered from unweaned pigs, and once from a sow. Organisms of the O-138 type produced heat labile enterotoxin and their presence in weaned pigs was associated with the development of severe post-weaning diarrhoea. E. coli of O-139 type produced a vero cell cytotoxin and were associated with a milder diarrhoea in weaned pigs. Under various managemental circumstances the O-138 type E. coli almost invariably proliferated after weaning. The O-139 strain of E. coli did however proliferate rather than the O-138 strain following the movement of weaned pigs to new accommodation, after weaned pigs were returned to their sow and then weaning again 5 days later, and very occasionally in pigs weaned at 5 weeks of age. In all these cases earlier proliferation of the O-138 E. coli had been detected, suggesting that this may be a prerequisite for proliferation of the O-139 strain.  相似文献   
64.
Polyclonal antibodies directed against human recombinant basic fibroblast growth factor were used in immunohistochemical studies to localize this growth factor in normal and wounded rat skeletal muscles. According to the intensity of the stain, three main classes of fibers could be identified: the strongly, moderately, and weakly stained fibers. Basic fibroblast growth factor immunoreactivity was found mainly in the extracellular matrix, primarily in the endomysium, which includes the heparin-containing basal lamina, and also in the capillary basal membrane of both normal and wounded muscles; however, the signal intensity was much stronger in normal muscles. The distribution of basic fibroblast growth factor in wounded muscles became markedly heterogeneous and sparse. After 4 hours of ischemia, about 40% of skeletal muscle fibers lost their basic fibroblast growth factor immuno-reactivity. Muscles which underwent 4 hours of ischemia and 24 hours of reperfusion had only a diminished basic fibroblast growth factor immunoreactivity. The pathologic results supported the concept of destroyed cell connection and fiber necrosis in ischemic and reperfused muscles. Potential mechanisms involved in this reduced concentration of basic fibroblast growth factor in wounded muscles may include oxygen free radical activation, a generalized effect of the inflammatory response, and reduced secretion of endogenous basic fibroblast growth factor. These results are only partially compatible with the established mitogenic role of this growth factor and suggest that a reduction of endogenous fibroblast growth factor may partly contribute to a delay in wound healing.  相似文献   
65.
Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai, China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fungi. They were also examined for aflatoxin, endotoxin, and potential to stimulate production of human interleukin 1 beta (IL-1 beta) and to consume complement. The concentrations of total microorganisms were consistently greater than 10(7) CFU/g and ranged from 10(7) to 10(9) CFU/g. In general, the level of microbial contamination was greater in the hay dust samples than in the rice dust samples, with bacteria being the most numerous microorganisms observed followed by molds, thermophilic actinomycetes, and yeasts. The predominant fungi were species of Aspergillus, Cladosporium, Penicillium, Trichosporon, and Cryptococcus. No significant levels of aflatoxin were observed and the isolates of A. flavus examined lack significant aflatoxigenic potential. The levels of microorganisms in these samples, the types of organisms found, and the inflammatory mediators such as endotoxin suggest that workers exposed to these dusts may be at risk for respiratory illness.  相似文献   
66.
Soluble lens crystallins from 6-10-week-old, galactose-fed, male Sprague-Dawley rats were analyzed by two-dimensional polyacrylamide gel electrophoresis at each of the five Sippel stages of cataractogenesis. Electrophoretograms were compared with similarly analyzed crystallins from comparably aged, chow-fed controls. Polypeptides were assigned to crystallin families and subfamilies on the basis of chromatographic fractionations with Sephadex G-200, superfine. Staining intensities of polypeptides from control lenses remained essentially unchanged throughout the experimental period, while those of the polypeptides from cataractous lenses showed non-uniform changes. Staining of the genomic gamma-crystallins increases up to at least stage 3; by stage 4, staining of gamma-chains, with perhaps those of gamma 5 and gamma 6 excepted, diminishes and in the total cataract, staining of all chains is further reduced. With possibly the addition of one chain, the total number of postsynthetically modified gamma-crystallins in cataractous lenses does not exceed that in the comparably aged normal lens. The genomic alpha- and beta-crystallin polypeptides are sustained close to normal levels up to stages 3 or 2, respectively, after which their gradually falling levels are accompanied by the generation of new species or elevated levels of existing post-translational species. An exception to this behavior is the rapid and total loss of beta B1a, a genomic subunit implicated in the aggregation of beta H-crystallins. Charge heterogeneity and variable pI displayed by beta B1a and other highly cationic beta- and gamma-crystallin polypeptides can be induced during isoelectric focusing and may be due to thiol group oxidation.  相似文献   
67.
G Li  Y C Shen  Y T Li  C H Chen  Y W Zhau  J M Silverman 《Neurology》1992,42(8):1481-1488
We conducted a case-control study to assess possible factors associated with Alzheimer's disease (AD) with 70 clinically diagnosed AD patients and 140 age- and sex-matched nondemented neighborhood controls in China. Factors significantly associated with AD cases were family history of dementia in first-degree relatives, family history of psychotic disorders in first-degree relatives, and left-handedness/ambidexterity. A history of arthritis showed a significantly negative association with AD. Neither a family history for Down's syndrome, history of head trauma, nor other conditions that might support immune or viral hypotheses in AD were significantly associated with AD cases. These data support the role of familial/genetic factors in AD.  相似文献   
68.
本文采用中和试验、沉降反应和解离试验对135例已知血型人精液中ABH血型物质的分泌强度进行了检验,并将其分为强、中、弱三型。这对区别个人血型物质含量及性犯罪的法医学鉴定均有重要意义。并证明了AB型人精液中A、B血型物质含量不均等现象,并且绝大多数人B型物质高于A型物质。  相似文献   
69.
After eliminating confounding factors, the study was made on the relationship between height, collagen metabolism, hair zinc and excessive fluoride intake. 140 schoolchildren aged 12-13 years born and reared in endemic fluorosis areas were surveyed. The results were as follows: 1. The average height of children with dental fluorosis III degree (DF III degree) was appreciably smaller than that of children without dental fluorosis. Among children with excessive fluoride intake, a negative correlation between the height and fluoride level in staple foods was seen. 2. The more the fluoride ingested, the higher the urinary THP excreted, showing that fluoride intoxication interfered with the collagen metabolism. 3. Among children with excessive fluoride intake, the height showed negative correlation with urinary THP/Cr, suggesting that the effect of fluoride on collagen metabolism indicated the mechanism of height retardation. 4. As compared to control group with the excessive fluoride intake but without dental fluorosis group, there was a significant reduction in hair zinc in group with DF III degree, suggesting that the zinc in the body decreased because of zinc metabolism disturbance by excessive fluoride intake. But among cases with excessive fluoride intake, no appreciable correlation between hair zinc and height was found. Therefore, it could not be confirmed that the effect of fluoride on zinc metabolism affected the height development.  相似文献   
70.
分析了1984~1993年期间47例经治的急性视神经炎患者。治疗应用地塞米松10mg、青霉素480万u静脉点滴7天,随后减量。结果治愈35例(74.47%),好转6例(12.76%),无效2例(4.26%),转院及自动出院各2例。47例中11例治疗效果不好者行筛窦开放术后,视力逐渐恢复正常,显示筛窦开放术有其临床实用价值。  相似文献   
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