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In this article the results of the study of regularities in the development of outbreak morbidity in shigellosis, caused by S.flexneri 2a, in hospitals are presented. The study was carried out with the use of the method of typing by the plasmid profile. The study showed the continuity of the epidemic process in the foci which appeared at intervals considerably exceeding the incubation period. The fact of the interhospital spread of S.flexneri 2a was established. The strain causing the disease was identified by the characteristic set of plasmids and their size. The possibility of reinfection of patients with S.flexneri 2a under hospital conditions was confirmed. The possibility of changes in the main transmission routes in the course of the spread of S.flexneri 2a infection in closed groups was pointed out.  相似文献   
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OBJECTIVES: In this B-mode ultrasound study we assessed pravastatin treatment effects on carotid and femoral artery walls and investigated the correlations between the state and evolution of peripheral and coronary atherosclerosis. BACKGROUND: The Regression Growth Evaluation Statin Study (REGRESS) was an 11-center, 2-year, double-blind, placebo-controlled, prospective study of 885 men with coronary artery disease (CAD) (total cholesterol 4 to 8 mmol/liter). The study primarily investigated pravastatin treatment effects on the coronary lumen. This report focuses on the 255 patients who participated in the REGRESS ultrasound study. METHODS: Carotid and femoral artery walls were imaged at baseline and at 6, 12, 18 and 24 months. Pravastatin treatment effect was defined as the difference in progression of the combined intima-media thicknesses (IMT) between treatment groups. RESULTS: Pravastatin treatment effects were highly significant (combined IMT: p = 0.0085; combined far wall IMT: p < 0.0001; common femoral artery far wall IMT: p = 0.004). Correlations between the IMTs of the arterial wall segments ranged from -0.17 to 0.81. Baseline correlations between IMT and percent coronary lumen stenoses ranged from 0.23 to 0.36. Baseline IMT correlated with the mean coronary segment diameter (r = -0.32, p = 0.001) and minimal coronary obstruction diameter (r = -0.27, p = 0.005). There were no individual correlations between IMT and coronary lumen variables (p > 0.30). CONCLUSIONS: Pravastatin treatment effects on carotid and femoral artery walls were observed. B-mode ultrasound imaging studies of peripheral arterial walls could not describe the state and evolution of the coronary lumen in the individual patient, but proved to be a highly suitable tool for the assessment of antiatherosclerotic properties of agents.  相似文献   
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Computerizing an organization's policies and guidelines is difficult but rewarding. The assessment, planning, implementation, and evaluation of converting all paper policies and procedures into a computerized system are outlined, with particular focus on organizing guidelines according to the Joint Commission on Accreditation of Healthcare Organization's (JCAHO) functional standards.  相似文献   
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An investigation of the possible significance of 'stress' as a factor in the retention of bovine fetal membranes has been carried out, together with the investigation as to the possible variation of progesterone levels at parturition, as a cause of retention. No evidence of abnormal progesterone levels has been established, but from the evidence it is concluded that retention may well be yet another example of production disease.  相似文献   
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