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61.
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   
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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   
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Patients with depression have been extensively reported to be associated with the abnormality of omega-3 polyunsaturated fatty acids (PUFAs), including significantly low eicosapentaenoic acid and docosahexaenoic acid in cell tissue contents (red blood cell membrane, plasma, etc.) and dietary intake. However, more evidence is needed to support its relation. In this study, we conducted an 8-week, double-blind, placebo-controlled trial, comparing omega-3 PUFAs (6.6 g/day) [corrected] with placebo, on the top of the usual treatment, in 28 patients with major depressive disorder. Patients in the omega-3 PUFA group had a significantly decreased score on the 21-item Hamilton Rating Scale for Depression than those in the placebo group (P < 0.001). From the preliminary findings in this study, omega-3 PUFAs could improve the short-term course of illness and were well tolerated in patients with major depressive disorder.  相似文献   
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利用人T淋巴母细胞(Jurkat)细胞系作为研究对象。企图探探索细胞外基质成份及肌醇磷脂细胞信息传递系统与细胞移动的关系。研究结果表明:当细胞被伏波醇酯(PMA)处理过后,其粘连性与移动件对纤维连结蛋白(FN)底物的反应在已是高水平的基础上有更进一步提高的作用。与FN刊相反的是,未经PMA处理处的Jurkat细胞对层粘连蛋白(Lm)底物却无明显的粘连性及移动性增加的反应,尽管在PMA处理过4小时内亦无任何的增强。但是,当PMA作用于细胞24一48小时后则明显池增加其Lm底物的粘连性及移动性反应,表明了其明显的协同作用。分别用抗FN、抗Lm及蛋白激酶C抑制剂Staurosprine(SP)时均起到特异性的抑制作用。可见,协同作用的产生是通过蛋白激酶C激活后的-段时间内,使细胞表面Lm受体密度增加而对底物Lm反应增强所致。  相似文献   
68.
在青年学生中吸收优秀分子已成为高校党组织发展工作的重要组成部分,最近几年来,高中党建工作也不断发展。了解青年学生党建现状,更好地利用中学党建工作成果,提出了做好衔接工作的现实意义及对策措施。  相似文献   
69.
Recently, 2-halogenated deoxyadenosine analogs (F, Cl, and Br) have been shown to have antitumor activity. These analogs are phosphorylated by cells and are believed to exert their cytotoxic action at the nucleoside triphosphate level. In this work the interaction of these nucleoside triphosphate analogs with potential targets, such as DNA polymerase alpha, beta, and gamma, DNA primase, and ribonucleotide reductase was examined in detail. All of these compounds competitively inhibited the incorporation of dAMP into DNA by DNA polymerase alpha, beta, or gamma. F-dATP was able to completely substitute for dATP using DNA polymerase alpha and gamma, but not with DNA polymerase beta. Cl-dATP and Br-dATP substituted poorly for dATP using DNA polymerase alpha and beta. Extension of a 32P-labeled primer by DNA polymerase alpha, beta, or gamma on a single-stranded M13 template showed that these compounds were incorporated into the 3' end of the growing DNA chain and that elongation beyond the incorporated analogs was significantly retarded for Cl-dATP and Br-dATP using either DNA polymerase alpha or beta. DNA primase using poly(dC) as template was inhibited by these compounds at a concentration 4 to 5 times greater than that required for 2-F-araATP. The 2-halogenated dATP analogs were potent inhibitors of ADP reduction by ribonucleotide reductase. In conclusion, the cytotoxic action of 2-Cl-deoxyadenosine and 2-Br-deoxyadenosine may partially be mediated through the mechanism of "self-potentiation," by depression of the deoxynucleoside triphosphate pools due to inhibition of ribonucleotide reductase, which would facilitate their incorporation into DNA and result in the inhibition of DNA synthesis.  相似文献   
70.
Globoid cell leukodystrophy (GLD, Krabbe disease) is a severe demyelinating disease caused by a genetic defect of beta-galactocerebrosidase (GALC). To date treatment to GLD is limited to hematopoietic stem cell transplantation. Experimental approaches by means of gene therapy in twitcher mouse, an authentic murine model of human GLD, showed significant but only marginal improvements of the disease. To clarify whether the introduction of GALC could provide beneficial effects on the oligodendrocytes in GLD, we transduced twitcher oligodendrocytes by stereotactically injecting recombinant retrovirus encoding GALC-myc-tag fusion gene into the forebrain subventricular zone of neonatal twitcher mouse. In vivo effects of exogenous GALC on twitcher oligodendrocytes were studied histologically by combined immunostaining for the myc-epitope and the oligodendroglial specific marker, pi form of glutathione-S-transferase, at around 40 days of age. We show here that GALC transduction led to dramatic morphological improvement of the twitcher oligodendrocytes comparing with those in untreated twitcher controls. This study provided direct in vivo evidence that GALC transduction could prevent or correct aberrant morphology of oligodendrocytes in GLD which may be closely related to the dysfunction and/or degeneration of oligodendrocytes and the demyelination in this disease.  相似文献   
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