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751.
Recently, a shift in obesity treatment away from emphasizing ideal weight loss goals to establishing realistic weight loss goals has been proposed; yet, what constitutes “realistic” weight loss for different populations is not clear. This study examined notions of realistic shape and weight as well as body size assessment in a large community-based sample of African-American, Asian, Hispanic, and white men and women. Participants were 1893 survey respondents who were all dieters and primarily overweight. Groups were compared on various variables of body image assessment using silhouette ratings. No significant race differences were found in silhouette ratings, nor in perceptions of realistic shape or reasonable weight loss. Realistic shape and weight ratings by both women and men were smaller than current shape and weight but larger than ideal shape and weight ratings. Compared with male dieters, female dieters considered greater weight loss to be realistic. Implications of the findings for the treatment of obesity are discussed.  相似文献   
752.
A direct ELISA for plasma cortisol is described which is carried out in a standard 96 well microtitre plate. In this ELISA cortisol-thyroglobulin conjugate is immobilised to the microtitre plate and competes with cortisol in the standard or plasma sample for antibody binding sites. Following washing the rabbit cortisol antibody bound to immobilised cortisol is incubated with peroxidase labelled goat antirabbit IgG. Following further washing o-phenylenediamine is added, colour developed, and the plate read at 492 nm on a standard ELISA plate reader. This ELISA shows good agreement with RIA and its sensitivity, specificity and precision allow its use in the routine steroid laboratory.  相似文献   
753.
The cytokine interleukin-1 (IL-1 beta) increased prostaglandin production by decidual stromal cells in culture in a time and dose dependent manner. Optimum conditions for stimulation were found to be for 24 hours at a concentration of 100 pg IL-1 beta/ml. An apparent increase in cyclo-oxygenase enzyme synthesis accompanied the increase in prostaglandin production, and both changes were inhibited by the protein synthesis inhibitor cycloheximide. This implicates protein synthesis in the stimulatory effects of IL-1 beta, which may be mediated through the increase in cyclo-oxygenase enzyme. A pre-incubation period of 72 hours was found to be necessary to observe the stimulatory effect of IL-1 beta on prostaglandin production, but this did not seem to be due to any change in the sensitivity of the cells to IL-1 beta; the increase in the number of cyclo-oxygenase positive cells was the same if IL-1 beta was added on day 1, day 2 or day 3 of culture, even though prostaglandin production was not stimulated on day 1 or day 2. Cycloheximide increased prostaglandin production on the first two days of culture and had no effect on the third day of culture. This was interpreted as indicating that a factor inhibiting cyclo-oxygenase activity was synthesised during the initial period of culture, which prevented any increase in prostaglandin production following the increase in enzyme synthesis.  相似文献   
754.
755.
In a previous report we provided evidence that the three major hypoxanthine-guanine phosphoribosyltransferase (HGPRT; EC 2.4.2.8) isozymes in human erythroid cells are derived by posttranslational modification of a single enzyme [Johnson, G. G. et al. (1982). Biochemistry 21:960]. In the experiments reported here we provide further evidence that the modified isozymes have a catalytic activity that is at least as great as that of the unmodified enzyme. However, we also show that the total HGPRT activity decreases with red-cell age, by a factor of approximately 4, and that this decrease in activity is paralleled by a loss in HGPRT immunoreactive protein. We estimate that the loss of HGPRT activity and immunoreactive protein as well as the changes in the relative abundances of the major isozymes occur early in the cell's life.This work was supported by United States Public Health Service Grant 5 RO1 CA 16754-03 and by the San Diego State University Foundation.  相似文献   
756.
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758.
Reports of toxicity from the routine bathing of newborn infants with hexachlorophene resulted in discontinuing its use in the newborn nurseries of the Ottawa Civic Hospital, only to be followed by an outbreak of skin infections. As a result, a controlled trial of bathing newborn babies with either Lactacyd or pHisoHex was begun. The efficacy of the soaps was evaluated by comparing the colonization of the nose and umbilical cords of 158 pHisoHex-washed babies and 156 Lactacyd-washed babies on the day of discharge from hospital. The gram-negative and gram-positive bacterial flora of nose and cord of infants washed with pHisoHex and Lactacyd were identical in frequency and distribution.  相似文献   
759.
760.
Urinary levels of 11-keto-thromboxane B2 (11-keto-TXB2), were elevated at all gestational ages (12-41 weeks) compared with non-pregnant levels. 11-keto-TXB2 levels exceeded those of TXB2 throughout pregnancy, which suggested that 11-keto-TXB2 may be the major urinary metabolite of TXA2 in normotensive pregnancy, as in the non-pregnant state. This was reversed in women with mild pregnancy-induced hypertension (P.I.H.), such that urinary levels of TXB2 were higher (p less than 0.01) than those of 11-keto-TXB2. Since the 11-thromboxane dehydrogenase enzyme is found in the placenta, the low levels of 11-keto-TXB2 may be the result of placental damage decreasing the activity of the enzyme. The relationship between these findings and the aetiology of P.I.H. is not clear, but changes in urinary 11-keto-TXB2 may be of use in identifying those women at risk of developing P.I.H.  相似文献   
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