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c-erbB-2-positive breast carcinomas are highly aggressive tumors. In vitro data on breast cell lines showed that c-erbB-2 enhanced translational efficiency of hypoxia inducible factor-1alpha (HIF1alpha) production (Laughner et al., Mol Cell Biol 2001;21:3995-4005). We investigated the clinical correlate of this observation to assess whether c-erbB-2 expression was related to HIF1alpha expression, angiogenesis, and prognosis. A series of 180 breast carcinomas of known c-erbB-2 status (90 c-erbB-2-positive and 90 c-erbB-2-negative carcinomas) were stained immunohistochemically for HIF1alpha and CD31 endothelial cell antigen. c-erbB-2 positivity was clearly related to HIF1alpha protein expression and high angiogenesis. However, prognosis was decreased only in cases with simultaneous c-erbB-2 and HIF1alpha expression. If activation of c-erbB-2 in humans results in overexpression of HIF1alpha independently of conditions of hypoxia, as occur in experimental studies, this interaction may represent a main pathway conferring clinical aggressiveness to c-erbB-2-positive breast tumors.  相似文献   
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Background: Coronary angioplasty, although of proven use in partial occlusion, has not been shown to be of similar benefit in chronic total occlusion. Aims: To assess the utility of coronary angioplasty in chronically totally occluded vessels in patients undergoing angioplasty and to determine the success of TIMI-I flow before angioplasty compared to those patients with TIMI-O flow. Methods: A group of 178 consecutive patients (from 1984 to 1992), who underwent angioplasty of a chronic occlusion, were analysed. There were 136 males and 42 females with a mean age of 56.9 years. Results: Initial technical success was achieved in 65%. Patients with TIMI-I flow before angioplasty had a higher chance of success (700%) compared to those with TIMI-O flow (53%), p < 0.04. During hospitalisation six patients suffered myocardial infarction (MI), two required surgery and one patient died. During a mean follow-up of 2.8 years the overall survival rate was 95% for the group as a whole. Freedom from coronary surgery was significantly greater in patients with successful angioplasty (93%) than those without (66%, p < 0.002). The above two populations also showed a significant difference in the incidence of angina (35%vs 56%, p < 0.0003). However, the incidence of MI (6%vs 5%, p > O.5) and cardiac survival (98%vs 94%, p > 0.l) did not differ significantly in the two groups. Restenosis occurred in 63% of the 95 patients (82%) who returned for follow-up angiography. Eighteen of the 59 patients (28%) with restenosis had a reocclusion. Conclusion: The success rate for angioplasty of chronic total occlusions is acceptable. Long-term clinical benefit in patients with successful angioplasty is suggested by the high freedom from angina and the lesser need for coronary surgery. No major impact on either the incidence of MI or cardiac survival was noted when patients who had coronary surgery were included, although it must be emphasised that the sample size in this study was insufficient to detect a difference in these outcome variables.  相似文献   
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The elderly and individuals who have chronic obstructive pulmonary disease (COPD) may be sensitive to particulate matter (PM) air pollution. We evaluated short-term health responses of 13 elderly volunteers with COPD and 6 age-matched healthy adults to controlled exposures of ambient PM pollution in suburban Los Angeles. Using a Harvard particle concentrator and a whole-body chamber, we exposed each person on separate occasions to approximately 200 microg/m(3) concentrated ambient particles (CAP) less than 2.5 mum in diameter and to filtered air (FA). Each exposure lasted 2 h with intermittent mild exercise. We found no significant effects of CAP on symptoms, spirometry, or induced sputum. A significant negative effect of CAP on arterial oxygenation (measured by pulse oximetry) immediately postexposure was more pronounced in healthy subjects. Peripheral blood basophils increased after CAP in healthy but not in COPD subjects. In both groups, red cell counts increased slightly 1 day after exposure to FA but not to CAP. Preexposure ectopic heartbeats were infrequent in healthy subjects, but increased modestly during/after CAP exposure relative to FA. Ectopic beats were more frequent in COPD subjects, but decreased modestly during/after CAP relative to FA. Heart-rate variability over multi-hour intervals was lower after CAP than after FA in healthy elderly subjects but not in COPD subjects. Thus, in this initial small-scale study of older volunteers experimentally exposed to ambient PM, some acute cardiopulmonary responses were consistent with effects reported from epidemiologic studies. Unexpectedly, individuals with COPD appeared less susceptible than healthy elderly individuals. Further investigation of older adults is warranted to understand the pathophysiology and public health significance of these findings.  相似文献   
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PURPOSE: Accumulation of by-products of metabolism within skeletal muscle may stimulate sensory nerves, thus evoking a pressor response named muscle metaboreflex. The aim of this study was to evaluate changes in central hemodynamics occurring during the metaboreflex activation. METHODS: In seven healthy subjects, the metaboreflex was studied by postexercise regional circulatory occlusion at the start of the recovery from a mild rhythmic forearm exercise. Central hemodynamics was evaluated by means of impedance cardiography. RESULTS: The main findings of this study were that, with respect to rest, the metaboreflex: 1) raised mean blood pressure (+13%; P < 0.01); 2) enhanced myocardial contractility (-12% in preejection period/left ventricular ejection time ratio; P < 0.01); 3) prolonged diastolic time (+11%; P < 0.01); 4) increased stroke volume (+ 10%; P < 0.05); and 5) increased cardiac output (+6%; P < 0.05). These responses were present neither during recovery without circulatory occlusion nor during circulatory occlusion without prior exercise. Moreover, the metaboreflex did not affect systemic vascular resistance and induced bradycardia with respect to recovery without circulatory occlusion. CONCLUSION: These results suggest that the blood pressure response during metaboreflex activation after mild rhythmic exercise is strongly dependent on the capacity to increase cardiac output rather than due to increased vascular resistance.  相似文献   
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Minilaparoscopy-assisted natural orifice surgery.   总被引:5,自引:0,他引:5  
BACKGROUND AND OBJECTIVES: New technology has allowed us to perform major abdominal and pelvic surgeries with increasingly smaller instruments. The ultimate goal is surgery with no visible scars. Until current technical limitations are overcome, minilaparoscopy-assisted natural orifice surgery (MANOS) provides a solution. The aim of this study was to examine our clinical and experimental experience with MANOS. METHOD: Minilaparoscopic abdominal instruments were used together with a large vaginal port, which was used for insufflation, visual purposes, introduction of operative instruments, and specimen extraction. Minilaparoscopy-assisted intraperitoneal transgastric appendectomy was done in simulators (Lap trainer with SimuVision, Simulab Corp., Seattle, WA). RESULTS: Since 1998, we have used this technique in 100 cases including ovarian cystectomies, oophorectomies, salpingo-oophorectomies, myomectomies, appendectomies, and cholecystectomies. Some oophorectomies were performed after vaginal hysterectomy in cases where vaginal extraction was not possible. In this case series, we had only one complication, a case of postoperative fever after an ovarian cystectomy, which was diagnosed as drug-related fever. Our limited simulator experience showed that MANOS is a feasible technique for performing transgastric appendectomies. CONCLUSION: It may take several years for natural orifice surgery to become standard care. Meanwhile, MANOS could encourage and expedite this process.  相似文献   
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