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991.
OBJECTIVES: We examined the impact of gender on outcomes of patients undergoing percutaneous coronary intervention using sirolimus-eluting stents (SES). BACKGROUND: Although gender-specific differences in outcome after implantation of bare-metal stents (BMS) have been described, there are no data assessing outcomes of women treated with SES. METHODS: We performed a patient-level pooled analysis from 4 randomized SES versus BMS trials (RAVEL [Randomized Comparison of a Sirolimus-Eluting Stent with a Standard Stent for Coronary Revascularization], SIRIUS [SIRolImUS-coated Bx Velocity balloon expandable stent in the treatment of patients with de novo coronary artery lesions], E-SIRIUS [Sirolimus-eluting stents for treatment of patients with long atherosclerotic lesions in small coronary arteries], and C-SIRIUS [Canadian study of the sirolimus-eluting stent in the treatment of patients with long de novo lesions in small native coronary arteries]) and analyzed outcomes as a function of gender. RESULTS: Of 1,748 patients, 1,251 were men and 497 were women. A total of 878 patients were randomized to SES (629 men and 249 women), and 870 patients were randomized to BMS (622 men and 248 women). Compared with men, women were older and more frequently had diabetes mellitus, hypertension, and congestive heart failure. Although overall clinical outcomes were similar in both genders, treatment with SES was associated with significant (p < 0.0001) reductions in rates of in-segment binary restenosis both in women (6.3% vs. 43.8%) and in men (6.4% vs. 35.6%), resulting in a significant reduction in 1-year major adverse cardiac events, driven by a lower incidence of target lesion revascularization/target vessel revascularization in both genders. By multivariable analysis, female gender was not an independent predictor of in-segment binary restenosis or clinical outcomes regardless of stent type. CONCLUSIONS: In this analysis, despite less favorable baseline clinical and angiographic features in women compared with men, the angiographic and clinical benefits of SES were independent of gender.  相似文献   
992.
Among the earliest and most important stages during tumorigenesis is the activation of the angiogenic process, an event that is termed the "switch to the angiogenic phenotype." We have developed an in vivo system that can reliably recapitulate the stages in tumor development that represent this transition. Using this model, we have harvested and studied tumor nodules that can be distinguished from each other on the basis of their degree of vascularization. Angiogenic tumor nodules were characterized by the presence of capillary vessels as determined by factor VIII immunohistochemistry, and both angiogenic and proteolytic activities in vitro. In contrast, preangiogenic nodules were devoid of microvessels and showed little angiogenic or proteolytic activity in vitro. Addition of a specific metalloproteinase inhibitor resulted in the abrogation of both angiogenic and proteolytic activities of the angiogenic nodules in vitro. Comparative substrate gel electrophoresis detected the presence of a prominent matrix metalloproteinase (MMP-2) in the angiogenic nodules when compared with the preangiogenic ones. Suppression of MMP-2 activity by antisense oligonucleotides in the vascular nodules resulted in the loss of angiogenic potential both in vitro and in vivo in the chick chorioallantoic membrane assay. Moreover, this suppression of MMP-2 activity in angiogenic nodules inhibited tumor growth in vivo by approximately 70%. These results strongly implicate the activity of MMP-2 as a requirement for the switch to the angiogenic phenotype and validate this model as a reliable and reproducible tool by which to study other cellular and biochemical factors involved in the acquisition of the angiogenic phenotype.  相似文献   
993.
The MULTI-LINK DUET is the next generation MULTI-LINK stent with modified strut geometry. Safety and efficacy of the MULTI-LINK DUET were evaluated in a prospective multicenter registry and were compared with prior MULTI-LINK stent experience from the ASCENT randomized trial. A total of 270 patients received 302 MULTI-LINK DUET stents and were evaluated using a composite primary end point of major cardiac events (death, Q-wave and non–Q-wave myocardial infarction, and requirement for coronary revascularization) attributable to the target stenosis cumulative to 30 days following enrollment. Quantitative coronary angiography was performed at a mean follow-up of 6 ± 2 (±SD) months. No difference in primary end point or in angiographic restenosis to 6 months was observed between MULTI-LINK DUET and MULTI-LINK experiences. The MULTI-LINK DUET demonstrated improved device and procedural success, less postprocedural in-stent stenosis, larger postprocedural minimal lumen diameter, and fewer postprocedural marginal dissections compared with the MULTI-LINK stent. Multivariate regression modeling identified stent length, diabetes mellitus, poststent minimal lumen diameter, lesion eccentricity, and current smoking as independent predictors of in-stent restenosis. Thus, the MULTI-LINK DUET Registry demonstrates enhanced procedural performance with clinical and angiographic outcomes similar to those previously observed for the MULTI-LINK stent in the ASCENT randomized trial.  相似文献   
994.
OBJECTIVES: The purpose of this research was to determine the relative safety and efficacy of multiple (> or =2) overlapping Cypher sirolimus-eluting stents (SES) (Johnson & Johnson, New Brunswick, New Jersey). BACKGROUND: Overlapping coronary stents are common. The periprocedural and late clinical and angiographic consequences of overlapped coronary stents are not clearly defined, particularly for drug-eluting stents. METHODS: All patients enrolled into five clinical trials of the SES were analyzed. Three of these trials were prospective randomized comparisons of the SES to the bare-metal stent (BMS), and two were prospective non-randomized trials of SES-treated patients with historical controls. All clinical and angiographic outcomes in overlap-stent-treated patients were compared by stent type and with single-stent-treated patients for the same stent device. RESULTS: In all, 575 patients with stent overlap (337 SES, 238 BMS) and 1,162 patients with single stents (697 SES, 465 BMS) were analyzed. Stent overlap was associated with a greater late lumen loss in stent and more frequent angiographic restenosis regardless of stent type. Among overlap-stent-treated patients, the SES provided similar magnitude of restenosis benefit as observed for single-stent-treated patients. Overlapped SES was not associated with an increase in myocardial infarction. CONCLUSIONS: The strategy of SES overlap, when required, is both safe and efficacious in reducing restenosis with no increase in the incidence of myocardial infarction or major adverse cardiovascular events, when compared with a bare metal coronary stent prosthesis.  相似文献   
995.
Wasp sting anaphylaxis   总被引:2,自引:0,他引:2  
Ratnoff  OD; Nossel  HL 《Blood》1983,61(1):132-139
Profuse hemostatic defects were demonstrable 14 hr after wasp sting anaphylaxis. The patient's plasma contained an agent or agents that interfered with the action of thrombin, impeding the release of fibrinopeptide A from fibrinogen and the hydrolysis of the synthetic amide H-D-prolyl-L-phenylalanyl-L-arginine p-nitroanilide. This inhibitor could not be equated with known plasma inhibitors of thrombin nor with heparin. Additionally, the titers of nearly all other known clotting factors were reduced as compared to levels obtained after the patient's recovery. Of particular interest were profound reductions in the titers of proaccelerin (factor V) and high molecular weight kininogen. A normal titer of Hageman factor (factor XII) argued against participation of contact-activated mechanisms in the induction of the multiple abnormalities observed. Attempts to demonstrate the release of procoagulant or anticoagulant substances from the patient's convalescent blood, plasma, serum, or leukocytes upon challenge with wasp venom were unsuccessful. The observations reported confirm and extend information concerning hemostatic abnormalities in anaphylaxis, and point out the need to examine further this puzzling association.  相似文献   
996.
Increased ribonucleotide reductase (RR) activity has been linked with malignant transformation and tumor cell growth. Therefore, this enzyme is considered to be an excellent target for cancer chemotherapy. We have examined the effects of a newly patented RR inhibitor, trimidox (3,4,5-trihydroxybenzohydroxamidoxime). Trimidox inhibited the growth of human promyelocytic leukemia HL-60 cells with an IC50 of 35 mumol/L. Incubation of HL-60 cells with 50 mumol/L trimidox for 24 hours decreased deoxyguanosine triphosphate (dGTP) and deoxycytidine triphosphate (dCTP) pools to 24% and 39% of control values, respectively. Incubation of HL-60 cells with 20 to 80 mumol/L trimidox even up to a period of 4 days did not alter the distribution of cells in different phases of cell cycle. Sequential incubation of HL-60 cells with trimidox (25 mumol/L) for 24 hours and then with 10 mumol/L tiazofurin (an inhibitor of inosine monophosphate dehydrogenase) for 4 days produced synergistic growth inhibitory activity, and the cell number decreased to 16% of untreated controls. When differentiation- linked cell surface marker expressions were determined in cells treated with trimidox and tiazofurin, a significantly increased fluorescence intensity was observed for the CD 11b (2.9-fold). CD 33 (1.9-fold), and HLA-D cell surface antigens. Expression of the transferrin receptor (CD71) increased 7.3-fold in cells treated with both agents, compared with untreated controls. Our results suggest that trimidox in combination with tiazofurin might be useful in the treatment of leukemia.  相似文献   
997.
998.
Influence of smoking on predictors of vascular disease   总被引:8,自引:0,他引:8  
Beyond the already well-established strong causative relationship with cancer, smoking increases the risk for vascular disease. Smoking may act directly or adversely influence risk factors contributing to the development of vascular disease. Smoking causes endothelial dysfunction, dyslipidemia (decreased high-density lipoprotein cholesterol levels, hypertriglyceridemia and increased oxidation of low-density lipoprotein cholesterol) and platelet activation leading to a prothrombotic state. Smoking increases emerging risk factors (eg, fibrinogen, homocysteine, and high-sensitivity C-reactive protein) and increases insulin resistance and the risk of developing type 2 diabetes mellitus. The beneficial effects of statins and antioxidants (eg, vitamins C and E, beta-carotene) are counteracted by smoking. Smoking-induced alterations in growth factors, adhesion molecules, and even in genes can accelerate the progression of atherosclerosis. The aim of this review is to consider the adverse consequences of smoking on the factors predisposing to vascular disease and to emphasize the beneficial effects of smoking cessation.  相似文献   
999.

Background  

Recent clinical trials in Africa, in combination with several observational epidemiological studies, have provided evidence that male circumcision can reduce HIV female-to-male transmission risk by 60% or more. However, the public health impact of large-scale male circumcision programs for HIV prevention is unclear.  相似文献   
1000.
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