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11.
Ernst Heinrich; Ohshima Hiroshi; Bartsch Helmut; Mohr Ulrich; Reichart Peter 《Carcinogenesis》1987,8(12):1843-1845
In order to evaluate the effect of concurrent administrationof areca nut and sodium nitrite, a long-term feeding study wasconducted with 120 Syrian hamsters. The animals were dividedinto four treatment groups, each consisting of 15 males and15 females, and received 2 g/kg diet of sodium nitrite (groupI), 20 g/kg diet of powdered areca nut (group II), 2 g/kg dietof sodium nitrite plus 20 g/kg diet of areca nut (group III)or powdered diet only (group IV) throughout their lifetime.Urine samples from all groups were analysed for N-nitrosonipecoticacid (NNIP), a major urinary metabolite of areca-nut-derivednitrosamines. NNIP was only detected in the urine of hamstersfed nitrite plus areca nut (concentration: 1.9±0.9 ng/mlurine), indicating that areca nut alkaloids underwent in vivonitrosation to form arecanut-specific nitrosamines. The totaltumour response was not significantly elevated in groups IIand III. Hamsters of group III had a markedly, but also insignificantlyhigher frequency of malignant tumours than those of the othergroups, with a statistically significant increase in malignantlymphomas in the males. Although limited by the low number ofanimals per group, these results indicate that exposure to nitritetogether with areca nut constituents appears to enhance therisk of developing malignancies. 相似文献
12.
R A Mohr 《Health services management research》1994,7(2):79-90
A causal model of the institutionalization process is presented. Path analysis and logistic regression are performed on NHIS Longitudinal Study of Aging data. Based on initial analysis, the model is revised and re-evaluated. Convergent results support significance for four of five proposed predictors. Results are similar for men and women. Findings suggest unidentified factors are important to nursing home admission and that attention should be given to the process of decision-making that leads to admission. 相似文献
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Preoperative evaluation of pulmonary risk factors 总被引:3,自引:0,他引:3
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Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial 总被引:4,自引:0,他引:4
K C Petruk M West G Mohr B K Weir B G Benoit F Gentili L B Disney M I Khan M Grace R O Holness 《Journal of neurosurgery》1988,68(4):505-517
A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p less than 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p less than 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients. Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
20.
Uta Hpken Michael Mohr Andreas Strüber Hildegard Montz Hilmar Burchardi Otto Gtze Martin Oppermann 《European journal of immunology》1996,26(5):1103-1109
The complement activation fragment C5a was recently shown to induce interleukin (IL)-6 synthesis by peripheral blood mononuclear cells. To understand better the role of C5a in cytokine regulation in vivo, we investigated the effects of complement depletion by cobra venom factor (CVF) or of anti-C5a monoclonal antibodies (mAb) on IL-6 generation in an animal model of septic shock. Complement-depleted pigs which were subsequently challenged with Escherichia coli generated significantly (p < 0.05) less IL-6 during the 6-h observation period than complement-sufficient controls. To address specifically the role of C5a in IL-6 regulation, we produced a C5a(57–74) peptide-specific mAb (T13/9) which neutralizes the bioactivity of porcine C5a. The mAb T13/9 does not crossreact with the precursor protein C5. The pretreatment of pigs with anti-C5a mAb T13/9 prior to the induction of sepsis resulted in a decrease of over 75 % in serum IL-6 bioactivity compared to control animals (p < 0.0001). These results indicate a role for C5a in the modulation of IL-6 synthesis in Gram-negative bacteremia. 相似文献