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A large pediatric residency program conducted an extensive analysis of the reliability and validity of the rating forms used to evaluate the pediatric residents enrolled in the program. Analyses were conducted on groups of residents who took the Pediatric In-Training Program (PITE) from 1977 through 1981. An average of 7.1 faculty members rated each resident on a standard form. The data indicate that although the reliability of individual ratings is very low, several factors achieved acceptable levels of reliability when aggregated. The first-year rating of history-taking ability correlated significantly with the PITE but ratings for more advanced residents did not correlate with PITE scores, mostly because of ceiling effects.  相似文献   
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Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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Chronically hypoxic (CH) and normoxic control rats were used to assess the action of S9581, a water-soluble analogue of almitrine bismesylate. S9581 increased ventilation (Ve) by 34% in control and 20% in CH rats. During acute hypoxia Ve was raised and S9581 caused a further increase of 20% in both groups. Low doses of S9581 and almitrine enhanced the hypoxic ventilatory response in CH rats while high doses depressed it in both groups. Effects of S9581 on the pulmonary circulation were assessed in the isolated perfused lung of rats. As with almitrine a complex relationship of dose-dependent vasoconstriction and dilatation was revealed. In low doses, S9581 enhanced the hypoxic pulmonary vasoconstrictor response to 2% O2 whilst this was attenuated by high doses in both control and CH rats. S9581 seemed to act like almitrine bismesylate on both the ventilation (peripheral chemoreceptor) and the pulmonary circulation. For studying almitrine-like activity the water solubility of S9581 provides considerable advantages for the researcher.  相似文献   
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Bee G 《The Journal of nutrition》2000,130(12):2981-2989
We evaluated the effects of conjugated linoleic acid (CLA) on growth performance, tissue fatty acid composition and ex vivo lipogenic enzyme activity in piglets (n = 40) reared on sows fed diets supplemented with CLA or linoleic acid (LA). Weaned offspring of both sow groups were offered either a CLA- or LA-enriched starter diet for 35 d. The starter diets were formulated to contain 2 g CLA (containing 58.9 g CLA/100 g total fatty acids) or LA per 100 g feed. All piglets were slaughtered at 70 d of age and tissue samples of the back fat, omental fat and longissimus dorsi were collected. Irrespective of the dietary fat supplied in the starter period, piglets reared on the CLA sows had greater final body and warm carcass weights (P: < 0.01), and greater feed intake (P: = 0.02) than piglets reared on the LA sows. The dietary effect on the fatty acid composition was similar for the adipose and muscle tissues. Compared with the LA-enriched diets, CLA increased the level of total saturated fatty acids (P: < 0.05), whereas that of monounsaturated fatty acids was decreased (P: < 0.05). Dietary CLA increased glucose-6-phosphate dehydrogenase (P: < 0.01) and malic enzyme activities (P: < 0.06) in the fat tissues, but did not affect fatty acid synthase activity. The shift toward a higher deposition of saturated fatty acids and a lower deposition of monounsaturated fatty acids is the result of down-regulation of Delta9-desaturase activity that was induced by CLA rather than an altered rate of de novo synthesis.  相似文献   
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[This corrects the article on p. 115 in vol. 1, PMID: 22053307.].  相似文献   
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