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排序方式: 共有928条查询结果,搜索用时 62 毫秒
921.
Moghadasian MH Nguyen LB Shefer S Salen G Batta AK Frohlich JJ 《Metabolism: clinical and experimental》2001,50(6):708-714
We compared hepatic cholesterol metabolism in apolipoprotein (apo) E-knockout (KO) mice with their wild-type counterparts. We also investigated the effects of treatment with phytosterols or probucol on the activity of hepatic 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase (cholesterol synthesis), cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase (bile acid synthesis), and low-density lipoprotein (LDL) receptor function in this animal model of atherogenesis. These findings were then related to treatment-induced changes in plasma, hepatic, and fecal sterol concentrations. Mouse liver membranes have binding sites similar to LDL receptors; the receptor-mediated binding represents 80% of total binding and is LDL concentration-dependent. These binding sites have higher affinity for apo E-containing particles than apo B only-containing particles. Deletion of apo E gene was associated with several-fold increases in plasma cholesterol levels, 1.5-fold increase in hepatic cholesterol concentrations, 50% decrease in HMG-CoA reductase activity, 30% increase in cholesterol 7 alpha-hydroxylase and 25% decrease in LDL receptor function. Treatment of apo E-KO mice with either probucol or phytosterols significantly reduced plasma cholesterol levels. Phytosterols significantly increased the activity of hepatic HMG-CoA reductase, and probucol significantly increased cholesterol 7 alpha-hydroxylase activity. Neither treatment significantly altered hepatic LDL receptor function. Phytosterols, but not probucol, significantly increased fecal sterol excretion and decreased hepatic cholesterol concentrations. Plasma cholesterol lowering effects of phytosterols and probucol are due to different mechanisms: stimulation of cholesterol catabolism via increased bile acid synthesis by probucol and decreased cholesterol absorption by phytosterols. In the absence of apo E, hepatic LDL receptors could not be upregulated and did not contribute to the cholesterol lowering effects of either agent. 相似文献
922.
Appelbaum FR; Fefer A; Cheever MA; Buckner CD; Greenberg PD; Kaplan HG; Storb R; Thomas ED 《Blood》1981,58(3):509-513
Eight patients with disseminated non-Hodgkin's lymphoma who failed conventional combination chemotherapy were treated with high-dose chemotherapy, a supralethal dose of total-body irradiation, and a bone marrow transplant from a normal identical twin. Seven patients experienced complete remission. Four of the seven patients (two with diffuse poorly differentiated lymphocytic lymphoma, one with composite lymphoma, and one with diffuse moderately well differentiated lymphocytic lymphoma) remain in complete unmaintained remission 12-126 mo from transplantation. One patient relapsed after 10 mo but was retreated and is alive in unmaintained complete remission 73 mo from transplantation. One patient died of Pseudomonas pneumonia while in complete remission and one patient relapsed and died of progressive lymphoma. These results demonstrate that intensive chemoradiotherapy and twin marrow transplantation can induce frequent and enduring remissions in patients with disseminated non-Hodgkin's lymphoma who have failed conventional therapy. 相似文献
923.
924.
Storb R; Deeg HJ; Thomas ED; Appelbaum FR; Buckner CD; Cheever MA; Clift RA; Doney KC; Flournoy N; Kennedy MS 《Blood》1985,66(3):698-702
Forty-eight patients with chronic myelocytic leukemia, aged 11 to 47, were treated with high-dose cyclophosphamide and fractionated total body irradiation, followed by infusion of marrow from HLA-identical siblings. They were randomized to receive either methotrexate (MTX) (n = 23) or cyclosporine (CSP) (n = 25) as postgrafting prophylaxis for graft-v-host disease (GVHD). All patients had evidence of sustained hematopoietic engraftment. Seventeen of the 25 patients receiving CSP and 17 of the 23 patients receiving MTX are alive between one and almost four (median, 1.7) years, with an actuarial survival rate at three years of 62% and 66%, respectively (P = .60). Also, with respect to most other parameters studied, the two drugs were identical. The probability of acute GVHD was .42 and .46, respectively (P = .70), that of chronic GVHD, .50 and .63 (P = .44), and that of death from transplant-related causes, .30 and .24 (P = .51). There were no differences in the speed of granulocyte and platelet engraftment (P = .82 and .94, respectively), and the duration of hospitalization was comparable (P = .58). Patients receiving MTX required red cell transfusions for a shorter period of time (P = .02), but had a slightly increased morbidity from early oral mucositis. The leukemia recurrence rates were comparable (P = .60). With the regimens used in this study, we conclude that CSP failed to reduce the incidence of GVHD and improve the survival of patients with chronic myelocytic leukemia when compared to results with standard MTX. 相似文献
925.
Systematic observation is increasingly used as a method to measure neighbourhood characteristics thought to influence health inequalities. This article reports on the theory-driven development of a new observation tool composed of reflective indicators of neighbourhood characteristics believed to influence inequalities in smoking. We also report the results of generalisability analyses conducted to estimate the reliability (inter-rater reliability and temporal stability) of the observation tool. We use the reliability results to reflect on the quality of the measures and on the theoretical anchors of the tool. We conclude by making recommendations to improve measures collected through systematic observation. 相似文献
926.
While empirical evidence continues to show that low socio-economic position is associated with less likely chances of being in good health, our understanding of why this is so remains less than clear. In this paper we examine the theoretical foundations for a structure-agency approach to the reduction of social inequalities in health. We use Max Weber's work on lifestyles to provide the explanation for the dualism between life chances (structure) and choice-based life conduct (agency). For explaining how the unequal distribution of material and non-material resources leads to the reproduction of unequal life chances and limitations of choice in contemporary societies, we apply Pierre Bourdieu's theory on capital interaction and habitus. We find, however, that Bourdieu's habitus concept is insufficient with regard to the role of agency for structural change and therefore does not readily provide for a theoretically supported move from sociological explanation to public health action. We therefore suggest Amartya Sen's capability approach as a useful link between capital interaction theory and action to reduce social inequalities in health. This link allows for the consideration of structural conditions as well as an active role for individuals as agents in reducing these inequalities. We suggest that people's capabilities to be active for their health be considered as a key concept in public health practice to reduce health inequalities. Examples provided from an ongoing health promotion project in Germany link our theoretical perspective to a practical experience. 相似文献
927.
The seventh documented case of babesiosis transmitted by transfusion is reported. Both the donor and the recipient are residents of Connecticut, where the presence of endemic babesiosis has only recently been established. As the range of Babesia microti, and its vector the Ixodes dammini tick, continues to expand, clinicians and blood bank directors should be aware that cases of transfusion-transmitted babesiosis may occur in newly endemic areas. 相似文献
928.