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991.
Review of moderate alcohol consumption and reduced risk of coronary heart disease: is the effect due to beer, wine, or spirits 总被引:1,自引:0,他引:1
OBJECTIVES: To review the effect of specific types of alcoholic drink on coronary risk. DESIGN: Systematic review of ecological, case-control, and cohort studies in which specific associations were available for consumption of beer, wine, and spirits and risk of coronary heart disease. SUBJECTS: 12 ecological, three case-control, and 10 separate prospective cohort studies. MAIN OUTCOME MEASURES: Alcohol consumption and relative risk of morbidity and mortality from coronary heart disease. RESULTS: Most ecological studies suggested that wine was more effective in reducing risk of mortality from heart disease than beer or spirits. Taken together, the three case-control studies did not suggest that one type of drink was more cardioprotective than the others. Of the 10 prospective cohort studies, four found a significant inverse association between risk of heart disease and moderate wine drinking, four found an association for beer, and four for spirits. CONCLUSIONS: Results from observational studies, where alcohol consumption can be linked directly to an individual's risk of coronary heart disease, provide strong evidence that all alcoholic drinks are linked with lower risk. Thus, a substantial portion of the benefit is from alcohol rather than other components of each type of drink. 相似文献
992.
This brief review summarizes the physiology and pharmacology of eicosanoids and describes how they have been tested for possible application in liver disease and transplantation. The objective is to trace the stepwise application from the laboratory to the bedside. Although many questions remain to be answered, the observations summarized in this article have opened up new and potentially rewarding prospects in application to liver disease. 相似文献
993.
SG Rijpkema MJ Molkenboer LM Schouls F Jongejan JF Schellekens 《Canadian Metallurgical Quarterly》1995,33(12):3091-3095
We developed a rapid and reliable method for the identification Borrelia burgdorferi sensu lato species in ticks. We used the DNA sequence polymorphism of the spacer region between 5S and 23S rRNA genes, which has been shown to be able to discriminate between eight genomic groups of B. burgdorferi sensu lato (D. Postic, M. Assous, P. A. D. Grimont, and G. Baranton, Int. J. Syst. Bacteriol. 44:743-752, 1994). Spacer DNA was amplified by PCR and was then hybridized to five membrane-bound oligonucleotides. The oligonucleotides were specific for B. burgdorferi sensu stricto, Borrelia garinii, Borrelia afzelii, and group VS116. A probe which reacted with all genomic groups of B. burgdorferi sensu lato was also used. Ninety-six ticks collected in the field were destructed by bead beating, and the supernatant was used directly in a PCR. B. burgdorferi sensu lato DNA was detected in 6 of 57 adult ticks (11%) and 9 of 39 nymphs (23%). B. garinii was found in three nymphs and four adults, three nymphs carried B. afzelii, and one adult and one nymph carried group VS116. Double infections with B. afzelii and group VS116 were found in two nymphs and one adult. Thus, our method can simultaneously identify three genomic groups of B. burgdorferi sensu lato in ticks collected in the field. This technique provides new ways to study the association of genomic groups present in ticks and the risk of Lyme borreliosis. 相似文献
994.
RM Siegel DA Martin L Zheng SY Ng J Bertin J Cohen MJ Lenardo 《Canadian Metallurgical Quarterly》1998,141(5):1243-1253
The death-effector domain (DED) is a critical protein interaction domain that recruits caspases into complexes with members of the TNF-receptor superfamily. Apoptosis can also be induced by expressing certain DED-containing proteins without surface receptor cross-linking. Using Green Fluorescent Protein to examine DED-containing proteins in living cells, we show that these proteins cause apoptosis by forming novel cytoplasmic filaments that recruit and activate pro-caspase zymogens. Formation of these filaments, which we term death-effector filaments, was blocked by coexpression of viral antiapoptotic DED-containing proteins, but not by bcl-2 family proteins. Thus, formation of death-effector filaments allows a regulated intracellular assembly of apoptosis-signaling complexes that can initiate or amplify apoptotic stimuli independently of receptors at the plasma membrane. 相似文献
995.
996.
997.
MJ Hickey AC Issekutz PH Reinhardt RN Fedorak P Kubes 《Canadian Metallurgical Quarterly》1998,83(11):1124-1131
The objective of this study was to determine whether endogenous IL-10 is capable of regulating hemodynamic parameters, leukocyte recruitment, and microvascular permeability in response to endotoxin. Intravital microscopy was used to examine hemodynamic parameters, leukocyte rolling and adhesion, and microvascular permeability in cremasteric postcapillary venules in wild-type mice and in IL-10-deficient (IL-10(-/-)) mice exposed to lipopolysaccharide (LPS). Doses of LPS (3 or 30 microg/kg, IV), which did not reduce blood pressure and minimally altered microvascular hemodynamic factors in wild-type mice, caused significant reductions in these parameters in IL-10(-/-) mice, demonstrating at least a 10-fold increased sensitivity in IL-10(-/-) mice to LPS-induced hemodynamic alterations. Furthermore, in response to LPS (30 microg/kg, IV), leukocyte rolling, adhesion, and fluorescein isothiocyanate-albumin extravasation were increased in the IL-10(-/-) mice. Antibody blockade experiments showed that in both types of mice, leukocyte rolling was mediated by E-selectin and P-selectin. Leukocyte accumulation into other tissues, such as lung, also was enhanced greatly in IL-10(-/-) mice. This was specific to endotoxin, because acute chemotactic stimuli including N-formyl-methionyl-leucyl-phenylalanine elicited similar responses in IL-10(-/-) and wild-type mice. These results suggest that endogenous IL-10 may be a homeostatic regulator of hemodynamic parameters, leukocyte-endothelial cell interactions, and microvascular dysfunction in response to endotoxin and provide potential mechanisms to explain the protective effect of IL-10 against LPS-induced mortality. 相似文献
998.
999.
The purpose of this study was to determine the acute effects of doxorubicin and its less cardiotoxic epimer, 4'-epirubicin, on the contractile response of isolated myocytes, and to assess similarities or differences with respect to active oxygen-derived mechanisms. Calcium-tolerant myocytes from rat ventricle were field stimulated at 1.0 Hz, and the maximum extent of cell shortening, peak shortening velocity, and peak relaxation velocity of single twitches were measured by video edge detection. The contractile responses of the myocytes to the two anthracyclines were approximately equal. Exposure of the cells to 10 microM of either anthracycline for 20 min decreased all indices of contractility by 28% (p < 0.05). The active oxygen scavengers, superoxide dismutase and catalase, distinguished the extent to which active oxygen was involved in modifying cellular contractility. Paradoxically, superoxide dismutase alone (10 U/mL) decreased contractility by 21%. Nevertheless, superoxide dismutase (10 U/mL) prevented the decreases in contractility produced by doxorubicin. In contrast, superoxide dismutase only mildly (32%) protected against 4'-epirubicin. Catalase (10 U/mL), however, provided substantial (82-93%) protection against both anthracyclines. Hydrogen peroxide therefore, and presumably hydroxyl radicals, were involved in mediating the decreases in contractility from both doxorubicin and 4'-epirubicin. These results show that an acute exposure to clinically relevant concentrations of these anthracyclines significantly depresses myocyte contractility and that, in this respect, 4'-epirubicin is as potentially cardiotoxic as doxorubicin. The results with antioxidant enzymes also strongly support a free radical mechanism for the toxicity of doxorubicin and 4'-epirubicin to cardiomyocytes. 相似文献
1000.
Carcinomas of peritoneal origin represent a seldom diagnosed entity of unknown etiology, with important implications in terms of prophylactic oophorectomy. Initially described in patients belonging to families at high risk for ovarian cancer, it possibly has a pathogeny similar to that of endosalpingiosis and of some cases of endometriosis. We report a case of peritoneal borderline mucinous carcinoma with an anatomopathological diagnosis of normal ovaries. 相似文献