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101.
102.
The roles chronological age and gender play in subjective time experience were explored in a sample of 294 adult men and women. Subjective time experience (STE: the difference between subjective age and chronological age) was found to vary widely among individuals, with some being "accurate" (SA = CA), and others either "retarded" (SA less than CA) or "advanced" (SA greater than CA). Males were more retarded in STE than females at every point in the lifespan, and patterns of age differences in adulthood differed for the two sexes as well. The results suggest that chronological age may play a key role in transitions in STE, and that chronological age is more significant in the STE of women than in the STE of men.  相似文献   
103.
Insect neuropeptides, having the common C-terminal sequence FXPRLamide X = V, T, S, or G), were tested for phyeromonotropic activity in the moth, Helicoverpa zea. Dose-response studies indicated that locustamyotropin-II or locustapyrokinin-II induced production of more pheromone than was stimulated by the pheromone biosynthesis activating neuropeptide of this moth. Other peptides showed various degrees of pheromonotropic activity. The data indicated that substitution of the variable amino acid in the C-terminal pentapeptide sequence resulted in significant differences in pheromonotropic activity. However, the overall structure of the peptide was also found to be of importance.  相似文献   
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Using a 3-wave longitudinal design, adolescents were studied over a 2-year period during which many first began to drink. Covariance structure modeling showed that teens' expectancy for social facilitation from alcohol and their drinking experience influenced each other in a reciprocal, positive feedback fashion: the greater the expectancy endorsement, the higher subsequent drinking levels, and the higher the drinking levels, the greater the subsequent expectancy endorsement. This model fit the data quite well; comparison models, in which expectancy (or drinking) had no independent influence on future drinking (or expectancy), showed significantly poorer fit than the present model. Initial nondrinkers' social expectancy predicted individual differences in the rate of drinking increase over the 2 years. Results bolster the hypothesis that expectancy actively influences drinking and point to the importance of expectancy-based intervention efforts.  相似文献   
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The aim of this study was to evaluate the prevalence of disordered intragastric meal distribution and the relationships between gastric emptying, intragastric distribution, glycemic control and gastrointestinal symptoms in diabetes mellitus. METHODS: Eighty-six patients with diabetes mellitus had measurements of gastric emptying and intragastric distribution of a radioisotopically labeled solid/liquid meal (100 g beef and 150 ml 10% dextrose), glycemic control (plasma glucose concentrations), upper gastrointestinal symptoms (questionnaire) and autonomic nerve function (cardiovascular reflexes). Results were compared to those obtained in 20 normal volunteers. RESULTS: Solid and liquid gastric emptying were delayed in the diabetic patients and correlated weakly. Intragastric meal distribution was also often abnormal, with increased retention of both solid and liquid in the proximal stomach and increased retention of solid but not liquid in the distal stomach. In all patients with increased retention of solid in the proximal stomach, emptying from the total stomach was delayed. Gastric emptying of liquid was slower in those subjects who had a mean plasma glucose > 15 mmol/liter during the gastric emptying measurement, when compared to the remainder of the group. CONCLUSION: In patients with diabetes mellitus, there is poor relationship between solid and liquid gastric emptying and intragastric meal distribution is frequently abnormal. Interpretation of the results of gastric emptying measurements should consider meal composition and plasma glucose concentrations.  相似文献   
108.
OBJECTIVE: To investigate why women who use crack cocaine are at increased risk of human immunodeficiency virus (HIV) infection. METHODS: One thousand one hundred fifty-two (99.7%) of 1155 consecutive prenatal patients attending a rural public health clinic were interviewed about drug use and sexual practices and tested for HIV infection and other sexually transmitted diseases. RESULTS: Fifty-one (4.7%) of 1096 pregnant women reported ever using crack cocaine, but only five (10%) of the crack cocaine users had ever injected drugs. Eighteen (35%) of the crack users were HIV infected compared with 22 (2%) of the 1045 women who reported never using crack (odds ratio 25, 95% confidence interval 12-52; P < .001). Crack users were more likely to have had a known HIV-infected sex partner, exchanged sex for money or drugs, and tested positive for syphilis than were non-crack users (for each comparison, P < .001). Before using crack, 18% of crack users had exchanged sex for money or drugs and 8% had averaged three or more sex partners per month; in contrast, after beginning to use crack, 76% of crack users exchanged sex for money or drugs and 63% averaged three or more sex partners per month (for both comparisons, P < .001). Crack users who were not HIV infected were more likely to have almost always used condoms and/or had fewer than three sex partners per month than were HIV-infected crack users (P < .01). CONCLUSION: Women who reported using crack cocaine were at an increased risk of HIV infection because crack use was associated with a significant increase in unprotected sexual contact.  相似文献   
109.
OBJECTIVE: The relationship between intentions to use alcohol and risk factors was examined among fifth and sixth graders. METHOD: Subjects completed a questionnaire that assessed intentions to use alcohol and eight risk factors. Risk factors included peer and parental use and attitudes toward use, sensation seeking, tolerance of deviance, rejection of parental authority, and family cohesion. RESULTS: Multivariate analyses showed that the risk factors were able to discriminate between those who intended to use alcohol and those who did not. Family factors showed stronger relationships to intentions among fifth graders, and peer factors were more strongly related to intentions among sixth graders. CONCLUSIONS: Risk factors can be used to target preadolescents who may be at risk for early alcohol use, and programs that attempt to prevent early initiation of alcohol use among adolescents can be designed.  相似文献   
110.
Inhalation of nail dust is a chronic problem facing podiatric physicians. This problem is compounded in physicians who develop allergic reactions to nail dust. This article defines atopy, reviews the characteristics of nail dust, and suggests methods to reduce the potential hazard that nail dust presents to the podiatric physicians and their employees.  相似文献   
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