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Aerobic exercise and normotensive adults: a meta-analysis   总被引:1,自引:0,他引:1  
Using the meta-analytic approach, the purpose of this study was to examine the effects of aerobic exercise on resting systolic (SYS) and diastolic (DIA) blood pressure in normotensive adults: The results of 35 human clinical training studies published in English-language journals between 1963 and 1992 and representing 1,076 subjects (800 exercise, 276 control) met criteria for inclusion. Across all categories and designs, statistically significant post-exercise reductions were found for both SYS and DIA blood pressure (mean +/- SD, SYS: -4.4 +/- 6.6 mm Hg, 95% CI, -6.2 to -2.6 mm Hg; DIA: -3.2 +/- 3.2 mm Hg, 95% CI, -4.0 to -2.2 mm Hg). When partitioned according to type of study: 1) (randomized controlled trials (RCT), 2) controlled trials (CT), and 3) no controls (NC), the following changes were noted: RCT, SYS: -4.5 +/- 7.2 mm Hg, 95% CI, -7.1 to -1.2 mm Hg; DIA: -3.8 +/- 2.9 mm Hg, 95% CI, -5.0 to -2.6 mm Hg; CT, SYS: -2.8 +/- 6.9 mm Hg, 95% CI, -10.0 to 4.4 mm Hg; DIA: -5.0 +/- 3.7 mm Hg, 95% CI, -8.9 to -1.1 mm Hg; NC, SYS: -4.7 +/- 6.1 mm Hg, 95% CI, -7.5 to 1.9 mm Hg; DIA: -1.7 +/- 3.0 mm Hg, 95% CI, -3.2 to -0.36 mm Hg. We concluded that aerobic exercise results in small reductions in resting SYS and DIA blood pressure among normotensive adults.  相似文献   
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496 case reports of patients operated upon for various kinds of intestinal obstruction were analysed. Complications were studied in 202 (40.6%) patients. 93 patients died (19.7%). Peritonitis remains to be the main cause of death postoperatively (49.5 per cent to all lethal issues).  相似文献   
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Common molecular and cellular targets for alkaloids sanguinarine and ellipticine, isolated from well-known antitumor plants (as well as from their various natural and synthetic derivatives), have been studied and described. Sanguinarine and ellipticine are characterized by significant biological activities including a high antitumor potential. Among the important targets of their action the following are to be noted. 1. DNA and other double helical polynucleotides. Due to the ability of DNA-intercalation sanguinarine, ellipticine and some of their derivatives can modify the double helical structures and topological forms of polynucleotides. The results of these modifications in intercalative complexes manifest themselves in the inhibition of numerous enzymatic reactions, dependent on the structures and topological forms of DNA and other polynucleotides. 2. ATP synthesis in mitochondria. Most of DNA-intercalators, including sanguinarine and ellipticine, belong to a group of penetrating (hydrophobic) cations, which are accumulated near the external side of inner mitochondrial membranes during the membrane energization. They neutralize negative charges, arising just as the inner mitochondrial membranes become energized. By this neutralization of membrane charges the ATP synthesis in inhibited and the oxidative phosphorylation renders to be uncoupled. All studied DNA-intercalators under certain conditions uncouple the mitochondrial oxidative phosphorylation. Apparent correlation between the agents' ability for DNA-intercalation and for mitochondrial ATP synthesis inhibition seems to be determined by the importance for both types of reactions of molecule hydrophobicity and positive charges. 3. Cholinesterase systems. Sanguinarine, ellipticine and some of their derivatives, like other DNA-intercalators studied, inhibit also the enzymatic activities of cholinesterase systems due to hydrophobicity and positive charges of their molecules. 4. Sanguinarine (and chelerythrine), are also capable of inhibiting the biological activity of SH-dependent enzymes and proteins. Due to the reactivity of iminium groups in sanguinarine and chelerythrine molecules with nucleophilic reagents, e.g. thiol groups of enzymes and other proteins, the activities of SH-enzymes and proteins are inhibited. In particular, sanguinarine and chelerythrine inhibit enzymatic activity of some SH-dependent ATPases, including membrane-bound cation-transport ATPases. The earlier accumulated experience of the application in medicine of plant saps and extracts containing these alkaloids, and of the treatment of many diseases (including benign and malignant tumors) by isolated alkaloids may be explained, to a certain extent, by the inhibition of activities of the above mentioned cellular targets. The selective toxicity of these alkaloids for the number of transformed cells can be explained in the same manner.  相似文献   
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Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was approximately 16% less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.  相似文献   
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Missing anterior teeth are being replaced by implant-supported restorations quite frequently in modern dentistry. Providing the patient with a temporary prosthesis prior to or following implant fixture placement must satisfy established esthetic and functional criteria. When orthodontic treatment is included as part of the overall treatment effort, additional considerations include the retention and stabilization of newly established tooth positions. This article describes the fabrication, use and advantages of a provisional anterior prosthesis that replaces missing teeth prior to or following implant placement.  相似文献   
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