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AIM: to investigate the influence of different experimental manipulations in a model of colonic experimental carcinogenesis with pharmacological induction in the rat. EXPERIMENTAL DESIGN: a total of 90 Sprague-Dawley male rats, divided into three groups, were used: non-surgical (n = 30); surgical with colonic trauma (n = 20), and surgical with colo-colonic anastomosis (n = 40). Carcinogenic induction was carried out with 1-2 dimethylhydrazine dihydrochloride. Colonic adenocarcinomas were identified and the number of tumors, as well as tumoral surface and percentage of tumoral surface was established. One-way ANOVA and Chi-square were employed for the statistical analysis. RESULTS: the number of tumors was greater in the surgical group than in the control group, and tumors preferentially developed around the manipulated colon. Surface and tumoral percentage were greater in the surgical group than in the control group, being also greater in the anastomosis group than in the group with colonic trauma. Within anastomosis groups, a greater tumor surface and percentage was found in the group with titanium than in the group with reabsorbable material. CONCLUSIONS: the experimental manipulation of the colon in rats enhances drug-induced colon carcingenesis. The creation of an anastomosis further increases the carcinogenic process compared with simulated anastomosis. This process is also enhanced by the quantity of suture material included in the anastomosis, and by the non-reabsorbable nature of the materials used in the anastomotic line.  相似文献   
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To evaluate the benefits of intravenous streptokinase (SQIV) in acute myocardial infarction (AMI), we joined a group of ten Mexican university hospitals, that were coordinated by the National Institute of Cardiology of Mexico. We included patients less than 70 years of age admitted to the hospital with less than 6 hours from the onset of chest pain during their first myocardial infarction. All patients had ST segment elevation of 1.5 mm or more, and none had contraindication for SQIV. They received 1.5 millions of SQIV in one hour. Reperfusion criteria included absence of pain, ST segment reduction and a rapid rise and fall of enzyme levels. Angiographic criterion for reperfusion was the permeability of the affected coronary vessel. Of 66 patients studied, 57 (86%) had clinical reperfusion; of the 24 available angiographic studies, 92% demonstrated reperfusion. Eight (12%) of the patients had minor complications and 7 (10%) had serious complications. There were 0 deaths. We concluded that SQIV is a useful therapeutic procedure, easy to perform in general hospitals.  相似文献   
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BackgroundAlthough intensive blood pressure reduction has cardiovascular benefits, the absolute benefit is greater in those at higher cardiovascular disease (CVD) risk.ObjectivesThis study examined whether N-terminal pro–B-type natriuretic peptide (NT-proBNP) helps identify subjects at higher risk for CVD events across systolic blood pressure (SBP), diastolic blood pressure (DBP), or pulse pressure (PP) categories.MethodsParticipants from the ARIC (Atherosclerosis Risk In Communities) study visit 4 (1996 to 98) were grouped according to SBP, DBP, or PP categories and further stratified by NT-proBNP categories. Cox regression models were used to estimate hazard ratios for incident CVD (coronary heart disease, ischemic stroke, or heart failure hospitalization) and mortality across combined NT-proBNP and/or BP categories, adjusting for CVD risk factors.ResultsThere were 9,309 participants (age: 62.6 ± 5.6 years; 58.3% women) with 2,416 CVD events over a median follow-up of 16.7 years. Within each SBP, DBP, or PP category, a higher category of NT-proBNP (100 to <300 or 300 pg/ml, compared with NT-proBNP <100 pg/ml) was associated with a graded increased risk for CVD events and mortality. Participants with SBP 130 to 139 mm Hg but NT-proBNP ≥300 pg/ml had a hazards ratio of 3.4 for CVD (95% confidence interval: 2.44 to 4.77) compared with a NT-proBNP of <100 pg/ml and SBP of 140 to 149 mm Hg.ConclusionsElevated NT-proBNP is independently associated with CVD and mortality across SBP, DBP, and PP categories and helps identify subjects at the highest risk. Participants with stage 1 hypertension but elevated NT-proBNP had greater cardiovascular risk compared with those with stage 2 SBP but lower NT-proBNP. Future studies are needed to evaluate use of biomarker-based strategies for CVD risk assessment to assist with initiation or intensification of BP treatment.  相似文献   
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