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Ningping Feng Diane Adler‐Wailes Jane Elberg Jeff Y. Chin Erica Fallon Alison Carr Teresa Frazer Jack A. Yanovski 《Obesity (Silver Spring, Md.)》2003,11(5):619-624
We investigated POMC sequence variants in 242 overweight and nonoverweight African‐American and white children and examined the associations between body composition and POMC polymorphisms. Three novel polymorphisms and two previously identified sequence variants were found: A7301G, A7429G, and C8246T were all in untranslated regions. A 9‐bp (AGC AGC GGC) duplication/insertion was found between positions 7677 and 7678, and one normal‐weight African‐American girl had a 45‐bp triple duplication/insertion at this location. Compared with whites, African‐American children were significantly more likely to have polymorphisms A7301G, A7429G, and the 9‐bp insertion. However, there were no significant associations between any of the polymorphisms and body composition. Five African‐American subjects who were homozygous for A7429G had a trend (p = 0.08) for a greater BMI‐SD score (5.3 ± 5.3 kg/m2) compared with wild‐type children (BMI‐SD score, 2.4 ± 3.2 kg/m2) or heterozygotes (BMI‐SD score, 2.7 ± 3.7 kg/m2). However, there were no differences in BMI‐SD score for A7429G when African American subjects were studied separately and both gender and height were taken into account. The contribution of the POMC gene variants we studied to pediatric‐onset obesity seems to be limited. 相似文献
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Retroviral serologic profiles were generated for 506 random-source cats (Felis catus) that were received by our facility during a twenty-month period. Feline leukemia virus antigens were detected in plasma samples from 26 (5.1%) of the cats. Antibodies to feline immunodeficiency virus were present in 24 (4.7%) of the samples tested. A single cat (0.2%) was positive for both viruses. Neither gender nor vendor correlation with retroviral seropositivity could be demonstrated. 相似文献
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Analysis of 2',5'-oligoadenylates in cells and tissues 总被引:2,自引:0,他引:2
Complex mixtures of 2',5'-oligoadenylates are formed in cells and tissues under several different circumstances, and methods for analyzing such mixtures are reviewed. Separation is achieved by high-performance liquid chromatography and quantitation by competition-binding assays, using three different types of antibodies or a specific binding protein, or by functional assay, using preparations of an endonuclease specifically activated by some of the 2',5'-oligoadenylates. Representative results from three different biological systems are presented. The function of 2',5'-oligoadenylates as activators of intracellular RNA degradation is discussed, along with the possibility that these compounds may serve as signals for other intracellular regulatory processes. 相似文献
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John D. Otis Howard W. Rasey Sam Vrochopoulos Jeff P. Wincze Frank Andrasik 《Applied psychophysiology and biofeedback》1995,20(2):185-190
Thermal biofeedback is widely used to treat various clinical disorders. Given its widespread utility, and the variability among the biofeedback systems currently on the market, it is important to investigate which systems are most effective for training various skills. This study compared the performance of normal subjects on two different computer-biofeedback systems. Results indicated a significant difference in subject performance between the two systems. Limitations and implications of these findings are discussed. 相似文献