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51.
The concept that complex surgical procedures should be performed at high-volume centers to improve surgical morbidity and mortality is becoming widely accepted. We wanted to determine if there were differences in the treatment of patients with gastric cancer between community cancer centers and teaching hospitals in the United States. Data from the 2001 Gastric Cancer Patient Care Evaluation Study of the National Cancer Data Base comprising 6,047 patients with gastric adenocarcinoma treated at 691 hospitals were assessed. The mean number of patients treated was larger at teaching hospitals (14/year) when compared to community centers (5–9/year) (p < 0.05). The utilization of laparoscopy and endoscopic ultrasonography were significantly more common at teaching centers (p < 0.01). Pathologic assessment of greater than 15 nodes was documented in 31% of specimen at community hospitals and 38% at teaching hospitals (p < 0.01). Adjusted for cancer stage, chemotherapy and radiation therapy were utilized with equal frequency at all types of treatment centers. The 30-day postoperative mortality was lowest at teaching hospitals (5.5%) and highest at community hospitals (9.9%) (p < 0.01). These data support previous publications demonstrating that patients with diseases requiring specialized treatment have lower operative mortality when treated at high-volume centers. Presented at the 47th Annual Meeting of the Society for Surgery of the Alimentary Tract, Los Angeles, CA, May 20–25, 2006 The members of the Gastric Patient Care Evaluation Group from the Commission on Cancer are as follows: Carol Conner Ph.D., M.D.; Thomas Habermann, M.D.; Scott A. Hundahl, M.D.; Martin S. Karpeh, Jr., M.D.; M. Margaret Kemeny, M.D.; Paul J. Kurtin, M.D.; Gregory Y. Lauwers, M.D.; Paul F. Mansfield, M.D.; Peter W. T. Pisters, M.D.; Andrew K. Stewart, M.A.; Zuo Feng Zhang, M.D.  相似文献   
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Context  As endogenous estradiol increases, risk of breast cancer increases. Raloxifene competes with endogenous estrogen for binding to estrogen receptors in breast tissue. A woman's estradiol level may alter the effects of raloxifene on breast cancer and other outcomes. Objective  To test the hypothesis that raloxifene reduces breast cancer risk more in women with relatively high estradiol levels than in women with very low estradiol levels. Design  Analysis of the Multiple Outcomes of Raloxifene Evaluation, a randomized, double-blind, placebo-controlled trial conducted from 1994 to 1999. Setting  One hundred eighty community settings and medical practices in 25 countries including the United States. Participants  A total of 7290 postmenopausal women aged 80 years or younger with osteoporosis who had baseline serum estradiol concentrations measured by a central laboratory using a sensitive assay. Women with a history of breast cancer or estrogen use were excluded. Intervention  Participants were randomly assigned to receive 60 mg/d or 120 mg/d of raloxifene (n = 4843) or matching placebo (n = 2447) for 4 years. Main Outcome Measure  New cases of histopathologically confirmed breast cancer in the treatment and placebo groups, stratified by estradiol levels. Results  In the placebo group, women with estradiol levels greater than 10 pmol/L (2.7 pg/mL) had a 6.8-fold higher rate of breast cancer (3.0% per 4 years; 95% confidence interval [CI], 1.8%-4.1%) than that of women with undetectable estradiol levels (0.6% per 4 years; 95% CI, 0%-1.1%; P = .005 for trend). Women with estradiol levels greater than 10 pmol/L in the raloxifene group had a rate of breast cancer that was 76% (95% CI, 53%-88%) lower than that of women with estradiol levels greater than 10 pmol/L in the placebo group (absolute rate reduction, 2.2% [95% CI, 1.0%-3.5%; number needed to treat = 45]). In contrast, women with undetectable estradiol levels had similar breast cancer risk whether or not they were treated with raloxifene (risk difference, -0.1%; 95% CI, -0.8% to 0.6%; P = .02 for the interaction). In this cohort, treating women with estradiol levels greater than 10 pmol/L with raloxifene for 4 years would have avoided 47% of breast cancer cases. Conclusions  Measurement of estradiol level by sensitive assay in postmenopausal women identifies those at high risk of breast cancer who may benefit most from raloxifene. If confirmed, this suggests that measuring estradiol and treating women with high estradiol levels could substantially reduce the rate of breast cancer among postmenopausal women.   相似文献   
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铅对大鼠脑突触体钙调素的抑制作用   总被引:1,自引:1,他引:0  
丁训诚  郑晔 《毒理学杂志》1993,7(4):209-211
用体外法,将大鼠脑突触体膜,在不同浓度的Pb~(2+)作用下分别测定CaM依赖的Ca~(2+)-ATP酶和CaM活性的IC_(50)值。结果表明,Pb~(2+)对Ca~(2+)-ATP酶活性IC_(50)为 1.62mM;对CaM活性IC_(50)为3.85mM。当向不含CaM的脑突触体加入3.0~10.0μg的外源性CaM后,被Pb~(2+)抑制的Ca~(2+)-ATP酶活性均有显著的逆转而恢复或接近正常水平。推测Pb~(2+)主要直接作用在脑突触体膜的CaM,通过CaM分子构象改变,抑制Ca~(2+)-ATP酶,这可能是铅神经毒性的分子基础。  相似文献   
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The purpose of these guidelines on the preoperative evaluation of the adult non-cardiac surgery patient is to present recommendations based on available relevant clinical evidence. The ultimate aims of preoperative evaluation are two-fold. First, we aim to identify those patients for whom the perioperative period may constitute an increased risk of morbidity and mortality, aside from the risks associated with the underlying disease. Second, this should help us to design perioperative strategies that aim to reduce additional perioperative risks. Very few well performed randomised studies on the topic are available and many recommendations rely heavily on expert opinion and are adapted specifically to the healthcare systems in individual countries. This report aims to provide an overview of current knowledge on the subject with an assessment of the quality of the evidence in order to allow anaesthetists all over Europe to integrate - wherever possible - this knowledge into daily patient care. The Guidelines Committee of the European Society of Anaesthesiology (ESA) formed a task force with members of subcommittees of scientific subcommittees and individual members of the ESA. Electronic databases were searched from the year 2000 until July 2010 without language restrictions. These searches produced 15?425 abstracts. Relevant systematic reviews with meta-analyses, randomised controlled trials, cohort studies, case-control studies and cross-sectional surveys were selected. The Scottish Intercollegiate Guidelines Network grading system was used to assess the level of evidence and to grade recommendations. The final draft guideline was posted on the ESA website for 4 weeks and the link was sent to all ESA members, individual or national (thus including most European national anaesthesia societies). Comments were collated and the guidelines amended as appropriate. When the final draft was complete, the Guidelines Committee and ESA Board ratified the guidelines.  相似文献   
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Context  Abciximab infusion and uncoated-stent implantation is a complementary treatment strategy to reduce major adverse cardiac events in patients undergoing angioplasty for ST-segment elevation myocardial infarction (STEMI). It is uncertain whether there may be similar benefits in replacing abciximab with high-dose bolus tirofiban. Similarly, the use of drug-eluting stents in this patient population is currently discouraged because of conflicting results on efficacy reported in randomized trials and safety concerns reported by registries. Objective  To evaluate the effect of high-dose bolus tirofiban and of sirolimus-eluting stents as compared with abciximab infusion and uncoated-stent implantation in patients with STEMI undergoing percutaneous coronary intervention. Design, Setting, and Patients  An open-label, 2 x 2 factorial trial of 745 patients presenting with STEMI or new left bundle-branch block at 16 referral centers in Italy, Spain, and Argentina between October 2004 and April 2007. Interventions  High-dose bolus tirofiban vs abciximab infusion and sirolimus-eluting stent vs uncoated stent implantation. Main Outcome Measures  For drug comparison, at least 50% ST-segment elevation resolution at 90 minutes postintervention with a prespecified noninferiority margin of 9% difference (relative risk, 0.89); for stent comparison, the rate of major adverse cardiac events, defined as the composite of death from any cause, reinfarction, and clinically driven target-vessel revascularization within 8 months. Results  ST-segment resolution occurred in 302 of 361 patients (83.6%) who had received abciximab infusion and 308 of 361 (85.3%) who had received tirofiban infusion (relative risk, 1.020; 97.5% confidence interval, 0.958-1.086; P < .001 for noninferiority). Ischemic and hemorrhagic outcomes were similar in the tirofiban and abciximab groups. At 8 months, major adverse cardiac events occurred in 54 patients (14.5%) with uncoated stents and 29 (7.8%) with sirolimus stents (P = .004), predominantly reflecting a reduction of revascularization rates (10.2% vs 3.2%). The incidence of stent thrombosis was similar in the 2 stent groups. Conclusions  In patients with STEMI undergoing percutaneous coronary intervention, compared with abciximab, tirofiban therapy was associated with noninferior resolution of ST-segment elevation at 90 minutes following coronary intervention, whereas sirolimus-eluting stent implantation was associated with a significantly lower risk of major adverse cardiac events than uncoated stents within 8 months after intervention. Trial Registration  clinicaltrials.gov Identifier: NCT00229515   相似文献   
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Colorectal cancer is an alcohol-related malignancy; however, the association appears to be stronger among Asian populations with a relatively high prevalence of the slow-metabolizing aldehyde dehydrogenase variant. To examine the association between alcohol consumption and colorectal cancer in Japanese, the authors analyzed original data from five cohort studies that measured alcohol intake using validated questionnaires at baseline. Hazard ratios were calculated in the individual studies, with adjustment for a common set of variables, and then combined using a random-effects model. During 2,231,010 person-years of follow-up (ranging variously from 1988 to 2004), 2,802 colorectal cancer cases were identified. In men, multivariate-adjusted pooled hazard ratios for alcohol intakes of 23-45.9 g/day, 46-68.9 g/day, 69-91.9 g/day, and > or =92 g/day, compared with nondrinking, were 1.42 (95% confidence interval (CI): 1.21, 1.66), 1.95 (95% CI: 1.53, 2.49), 2.15 (95% CI: 1.74, 2.64), and 2.96 (95% CI: 2.27, 3.86), respectively (p for trend < 0.001). The association was evident for both the colon and the rectum. A significant positive association was also observed in women. One fourth of colorectal cancer cases in men were attributable to an alcohol intake of > or =23 g/day. An alcohol-colorectal cancer association seems to be more apparent in Japanese than in Western populations. Whether this difference can be ascribed to genetic or environmental factors needs to be clarified.  相似文献   
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