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Abstract

The purpose of this study was to determine which of three intensities of treadmill training produced changes in body composition in rats as evidenced by body weight, percentage of fat and specific gravity. Subjects were 60 male Wistar rats 25 to 30 days old when obtained. They were randomly assigned to one of five groups: sedentary controls, spontaneously active controls, and three groups of rats forced to exercise on a treadmill at intensities of 75, 125 and 175 fpm. Forced exercise was applied three times a week for 8 weeks, after which measures of body weight, specific gravity, and percentage of body fat were obtained. Results indicated that the sedentary controls had significantly higher mean body weights than did those which exercised. Rats forced to exercise at 75 fpm had significantly lower specific gravity measures than rats trained at 125 fpm. Sedentary controls had lower specific gravity values than did all rats allowed to exercise. Intensity of treadmill training had no effect on percentage of body fat as determined chemically. However, exercise was effective in reduction of body fat.  相似文献   
184.
Marvin H. Caruthers 《Resonance》2012,17(12):1143-1156
??I wish to conclude by hazarding the following rather long range predictions. In the years ahead, genes are going to be synthesized. The next steps would be to learn to manipulate the information content of genes and to learn to insert them into and delete them from the genetic systems. When, in the distant future, all this comes to pass, the temptation to change our biology will be very strong.?? H G Khorana, 1968 [1]  相似文献   
185.
Most research in the area of higher education is plagued by the problem of endogeneity or self-selection bias. Unlike ordinary least squares (OLS) regression, propensity score matching addresses the issue of self-selection bias and allows for a decomposition of treatment effects on outcomes. Using panel data from a national survey of bachelor’s degree recipients, this approach is illustrated via an analysis of the effect of receiving a master’s degree, in various program areas, on wage earning outcomes. The results of this study reveal that substantial self-selection bias is undetected when using OLS regression techniques. This article also shows that, unlike OLS regression, propensity score matching allows for estimates of the average treatment effect, average treatment on the treated effect, and the average treatment on the untreated effect on student outcomes such as wage earnings.  相似文献   
186.
This article concerns itself with those personal variables of the consultant that are considered to be important to effective consultation. The personal characteristics that enhance a working, collaborative relationship are emphasized. Eleven considerations that are deemed important to the consultation process are described. Some comments on how personal variables of the consultant can be trained or modified to become more effective are then presented.  相似文献   
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