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81.
1984~1987年,在黑龙江、河北、河南、湖南、上海五个省市城乡10.08855人口中进行急性肝炎发病率、慢性肝炎患病率、与病毒性肝炎有关的肝病死亡率的研究。急性肝炎标化发病率为152.19/10万,主要发生在20~50岁组人群;因无甲肝暴发流行,除上海外各点季节发病率分布均衡。慢性肝炎标化患病率为158.25/10万(诊断标准为6个月前有明确急性肝炎病史,现有明显的临床症状或体征,肝功能异常,故实际慢肝患病率要高于此数字);与病毒性肝炎有关的肝病死亡(包括肝癌)标化率为22.65/10万,其中肝病为 13.14/10万。男性死亡率显著高于女性。  相似文献   
82.
以感染肾综合征出血热病毒(HFRSV)的Vero E6细胞为材料,用免疫亲和层析结合制备聚丙烯酰胺凝胶电泳(PAGE)从感染细胞中提纯了HFRSV两种糖蛋白。先用免疫亲和层析从感染细胞的粗制抗原中获得含有四种蛋白的混合液,用[~3H]-氨基葡萄糖在感染细胞中标记病毒糖蛋白,观察到[~3H]-氨基葡萄糖只结合入78K和57K的病毒蛋白。再用制备SDS-PAGE从HFRSV混合液中提纯78K和57K两种蛋白。实验证明这两种糖蛋白均具中和抗原决定簇,57K的糖蛋白尚具血凝活性,初步鉴定表明这两种糖蛋白相当于文献报道的HFRSV G_1和G_2。  相似文献   
83.
本文报道了病毒唑及其与干扰素联合对23例慢乙肝近、远期抗病毒效应观察结果,并与12例未经抗病毒治疗的慢乙肝作对照(Ⅲ组),其中病毒唑与干扰素联合组(I组)12例,病毒唑组(Ⅱ组)11例。近期HBeAg、DNAP及HBV·DNA阴转率,I组分别为(41.6%、55.5%及28.s%,Ⅱ组45.4%、100%及33.3%,Ⅲ组8.3%、16.6%及8.3%。远期HBeAg及DNAP阴转率在I组分别为70%、83.7%。Ⅱ组60%、100%,Ⅲ组8.3%,50%。综合抗病毒效应,近期有效率在I、Ⅱ、Ⅲ组分别为50%、72.7%及16.6%。远期则分别为70%、55.5%及8.3%。无一例出现毒副反应。均完成疗程。上述结果提示病毒唑及其与干扰素联合对慢乙肝均有一定抗病毒效应,联合应用并不优于单一用药,但毒副反应也未见加重,而且病毒唑药源较方便,使用较安全,值得进一步研究。  相似文献   
84.
Postmortem levels of native neopterin (D-erythro-neopterin) were measured in cerebral cortical samples from 44 human immunodeficiency virus type 1-infected and eight uninfected, nonneurological control patients. Cerebral cortical gray and white matter neopterin levels for the controls ranged from 0.5 to 7.2 pmol/mg of protein in contrast to neopterin levels in brains of the virus-infected patients, which frequently were more than threefold and occasionally more than 30-fold higher than mean control levels. Cortical neopterin levels did not correlate with severity of the acquired immunodeficiency syndrome dementia complex, but subcortical levels correlated with the presence of active human immunodeficiency virus type 1 infection, as reflected by pathological evidence of multinucleated giant cell encephalitis. Evidence of opportunistic cytomegalovirus infections in approximately 25% of the human immunodeficiency virus type 1-infected patients was associated with enhanced levels of neopterin in frontal cortex.  相似文献   
85.
Micro-element deficiencies have been implicated in the development of poor stem form in Pinus radiata plantations. Cu, Mn and B have been implicated in previous studies as influencing tree form and/or the process of lignification in plants. Therefore an experiment was initiated to examine the individual and interactive effects exhibited by these trace elements on stem form and lignification.The investigation showed that Cu deficiency reduced both lignification and stem form in seedlings. Mn, competing with Cu for uptake, enhanced the symptoms of Cu deficiency. Boron addition did not alleviate the expression of deformity or increase levels of lignification. There was a clear family influence on the development of seedling stem form in response to variations in mineral nutrition.  相似文献   
86.
DNA fork displacement rates were measured in three lines of Bloom's syndrome cells and in a normal diploid fibroblast line. Fork displacement rates in Bloom's cells were approx. 55–65% of the rate in normal fibroblasts.  相似文献   
87.
Summary A possible cause of non-disjunction of chromosome 21 in Down Syndromes has been cytogenetically evaluated by examining the parents by Ag-staining technique. In all the cases studied so far, the contributing parents have active ribosomal cistrons on both chromosomes 21 i.e. both chromosomes are stained positively by silver staining. These results show that the active NORs might play an essential role in meiotic non-disjunction. Furthermore, the preliminary results demonstrate that the acrocentric associations of homologous and non-homologous nature involving chromosome 21 are the most frequent in the contributing parent which may further indicate the role of multiple cellular factors affecting the associations in promoting the non-disjunction in addition to active NORs. The possible mechanisms regarding the non-disjunction of chromosome 21 have been described.Presented at the 34th Annual Meeting of the American Society of Human Genetics, Norfolk, VA, USA  相似文献   
88.
Since ACTH and the opioids display opposite effects on experimentally-induced seizures, cerebrospinal fluid (CSF) levels of ACTH and beta-endorphin (beta-EP) were measured in 6 children (4-8 months) affected by infantile spasms with hypsarhythmia, an idiopathic early onset encephalopathy, and in 8 age-matched controls. beta-EP levels in the patients (76.3 +/- 14.7 fmol/ml, M +/- SD) did not differ from those in controls (109.8 +/- 42.7) while babies with epileptic encephalopathy showed reduced ACTH levels in the CSF (3.8 +/- 1.5) as compared to controls (9.0 +/- 3.7, p less than 0.01). This resulted in an increased beta-EP/ACTH ratio. Another patient previously treated with ACTH showed a normal CSF level of ACTH (9.0) with a normal beta-EP/ACTH ratio while in clinical and EEG remission. These results are consistent with the hypothesis that some infantile seizures unrelated to brain injuries could originate from an ACTH deficiency at central level and/or an imbalance of neuropeptidergic pathways.  相似文献   
89.
《Free radical research》2013,47(10):1258-1266
Abstract

Objectives: The aim of the present study was to investigate the potential importance of oxidative stress, measured by isoprostanes-related compounds, as non-traditional risk factor for cardiovascular disease. We planned to examine the relationship between concentrations of plasma F2-isoprostanes (F2-IsoPs), isofurans (IsoFs), measures of obesity and various cardiometabolic risk factors. Materials and methods: Cross-sectional study using a sub-sample from the population of a survey conducted in the summer and fall 2007 and 2008 by Canadian Coastguard Ship Amundsen in 36 Canadian Arctic Inuit communities. Subjects included a subset (n =?233) of a total study population (n =?2595) with a mean age 42.56 ± 15.39 years and body mass index 27.78 ± 5.65 kg/m2. Plasma levels of F2-IsoPs and IsoFs was determined by gas chromatography/negative ion chemical ionization/mass spectrometry (GC/NICI/MS) method; and their relationships to waist circumference (WC), blood pressure C reactive proteins (CRP), blood lipids and fasting glucose were assessed by multivariate analyses. Results: Plasma F2-IsoPs correlated positively with CRP (r =.132, P =.048) and systolic blood pressure (SBP) (r =.157, P =.024) after adjustment for age, sex and body mass index. IsoFs correlated with WC (r =.190, P =.005) and SBP (r =.137, P =.048). F2-IsoPs were not found elevated in smokers (P =.034), whereas IsoFs were decreased in smokers (P =.001). WC, SBP and sex were found to be major correlates of oxidative stress in Canadian Inuit. Conclusions: Plasma measures of F2-IsoPs and IsoFs increase with increased obesity and associated cardiometabolic risk factors, including CRP and blood pressure. Simultaneous measurement of IsoFs provides an advantageous mechanistic insight into oxidative stress not captured by F2-IsoPs alone.  相似文献   
90.
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