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1.
Numerous dietary studies and several serum micronutrient studies have produced equivocal results on the relation of vitamins A and E to prostate cancer risk. To evaluate this association further, we conducted a nested case-control study in a cohort of 6860 Japanese-American men examined from 1971 to 1975. At the time of examination, a single blood specimen was obtained, and the serum was frozen. After a surveillance period of more than 20 years, 142 tissue-confirmed incident cases of prostate cancer were identified. Their stored sera and those of 142 matched controls were measured by high-performance liquid chromatography for the following: total carotenoids, lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, total retinoids, retinol, total tocopherols, alpha-tocopherol, delta-tocopherol, and gamma-tocopherol. Odds ratios for prostate cancer, based on quartiles of serum micronutrient levels, were determined using conditional logistic regression analysis. The odds ratio for the highest quartiles were 1.8 (95% confidence interval, 0.9-3.9) for beta-cryptoxanthin, 1.6 (0.8-3.5) for beta-carotene, 0.8 (0.4-1.5) for retinol, and 0.7 (0.3-1.5) for gamma-tocopherol, but none of the differences was statistically significant. For the other micronutrients, the results were also unremarkable. The findings of this study indicate that none of the micronutrients is strongly associated with prostate cancer risk.  相似文献   

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Chromosome painting has revealed that the human chromosome homologs in lesser apes are often fragmented and translocated to a number of different hylobatid chromosomes. We investigated the fragmented human chromosome 2 homologs in gibbons to illustrate a new strategy in mapping regional and band-specific chromosomal homologies between species. Previous research showed that the DNA library specific to human chromosome 2 paints parts of four gibbon (lar species group) chromosomes (viz., 1, 10, 12, and 16) and yields five distinct hybridization signals (including two on gibbon chromosome 16). However, the exact segments of human chromosome 2 that were translocated to the various gibbon chromosomes could not be distinguished. To determine the origin of the human chromosome 2 signals, we hybridized a microlibrary for the long arm of human chromosome 2, as well as YACs specific for most of the major bands on this chromosome, to metaphases of the gibbon. For reciprocal chromosome painting, we hybridized flow-sorted gibbon chromosome probes to human chromosome 2. Each method added additional insights that helped clarify the shuffling of human chromosome 2 material in the highly reorganized gibbon genome. There was an excellent correspondence between these complementary techniques. YAC 958d2 identified the breakpoint between human chromosome 2 material present on gibbon chromosomes 10 and 16. The reciprocal chromosome painting permitted a more complete and regional assignment of homology between segments on various gibbon chromosomes to human chromosome 2. The results show that a combination of reciprocal chromosome painting, subregional microlibraries, and band-specific probes (such as YACs) can be used to identify homologies between species and to rapidly construct detailed comparative chromosome maps, especially when the karyotypes are highly rearranged.  相似文献   

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Previous research on adolescents and their parents has indicated that pubertal maturation, independent of chronological age, is associated with increased distance in the parent–child relationship, but the cross-sectional nature of these studies leaves open questions concerning the direction of effects. Using short-term longitudinal data, this study examines the reciprocal relation between parent–child distance and pubertal maturation in a sample of 157 male and female firstborn adolescents and their parents. Twice over a 1-year period, independent raters assessed each youngster's pubertal status, and parents and adolescents independently completed questionnaire measures of autonomy, conflict, and closeness in the parent–child relationship. Regression analyses indicate that puberty increases adolescent autonomy and parent–child conflict and diminishes parent–child closeness. Analyses also indicate that parent–child distance may, in turn, accelerate pubertal maturation among girls. Both proximal and distal explanations for the relation between parent–child distance and pubertal maturation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Previous investigations of the association between parent and adolescent internalizing problems have been largely restricted to the unidirectional effect of parent symptoms on their children. This study therefore aimed to investigate potential reciprocal relationships between parent and adolescent internalizing symptoms. One-hundred and seventy-seven adolescents ages 14 to 18 years and their parents (172 mothers, 124 fathers) completed measures of depressive and anxiety symptoms at two time points, 6 months apart. Results supported reciprocity between maternal and adolescent internalizing symptoms but not between paternal and adolescent internalizing symptoms. In addition, the relationship between maternal symptoms and later adolescent symptoms was found to be partially mediated by maternal parenting self-esteem. The study highlights the potential impact of adolescent internalizing problems on maternal well-being, a phenomenon previously neglected in the literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Assessed the effect of co-occurring versus not co-occurring internalizing and externalizing behavior problems on the reasons parents reported for clinical referral of their adolescent child. Reasons for referral were coded for 181 inpatient adolescents, and parent ratings of internalizing and externalizing behavior were obtained for a general population sample of 500 adolescents. Parents concurrently reported internalizing and externalizing behavior as reasons for referral less frequently (p < .0001) than would be expected given the correlation between these two domains in the general population sample. This suggests that the presence of externalizing problems may decrease parents' concern or awareness of internalizing problems, the presence of internalizing problems may decrease parents' concern or awareness of externalizing problems, or both. Implications for the clinical referral of adolescents and for informal parental efforts at helping their children with externalizing and internalizing problems are discussed.  相似文献   

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Normal adult women showed systematic performance fluctuations across the menstrual cycle on several motor and perceptual tests that typically yield sex differences in performance. The midluteal phase, characterized by high levels of estradiol and progesterone, was associated with improved performance on tests of speeded motor coordination and impaired performance on a perceptual-spatial test, relative to performance during menses. Variations in gonadal steroid levels may contribute substantially to the sex differences reported in human cognitive and motor skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The present study examines reciprocal associations between marital functioning and adolescent maladjustment using cross-lagged autoregressive models. The research involved 451 early adolescents and their families and used a prospective, longitudinal research design with multi-informant methods. Results indicate that parental conflicts over child rearing predicted adolescent depressive symptoms and delinquency. In turn, these adolescent problems exacerbated parental conflicts over child rearing. Furthermore, conflict over child rearing served as the nexus through which more generalized marital dissatisfaction and adolescent adjustment problems were reciprocally interrelated. This research replicates earlier observations that marital problems intensify adolescent maladjustment and extends the literature by demonstrating that adolescent problems also predict marital conflict and ultimately marital dissatisfaction. In sum, the present study demonstrates that marital dissatisfaction, conflict over child rearing, and early adolescent adjustment difficulties are interwoven in a dynamic family system marked by reciprocity along these dimensions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Infection of macrophages with human cytomegalovirus (HCMV) has been shown to be nonlytic and exclusively cell associated. Human T cell leukemia-lymphoma virus type I (HTLV-I) is capable of establishing productive infection in macrophages. We studied the interactions between HCMV and HTLV-I in monocyte-derived macrophages cultured in vitro. We found that coinfection of macrophages with HCMV and HTLV-I significantly enhanced HCMV replication, resulting in release of infectious HCMV from dually infected cells. On the other hand, HCMV inhibited HTLV-I replication in macrophages coinfected with both viruses. Reciprocal interactions between HCMV and HTLV-I were mediated by their trans-acting proteins. Results of transfection studies demonstrated that the tax gene product of HTLV-I alone was capable of upregulating HCMV production. In a transient gene expression assay the immediate-early 2 (IE2) protein of HCMV alone could inhibit HTLV-I replication, whereas the IE1 protein, which had no effect by itself, produced a synergistic inhibitory effect together with the IE2 protein. Results from this study suggest that in vivo double infection of macrophages with HCMV and HTLV-I may contribute to the dissemination of HCMV infection in patients suffering from HTLV-I-associated T cell leukemia-lymphoma.  相似文献   

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Reports the death of Edward E. Cureton, who was a productive contributor to the literature of psychometrics, particularly in the areas of reliability, validity, and factor analysis. A diplomate in industrial psychology, Cureton was a fellow of Divisions 2 (Teaching), 5 (Evaluation and Measurement), 14 (Industrial), and 15 (Educational) of the American Psychological Association (APA) and was a fellow of the American Association for the Advancement of Science. He also served as president of the Psychometric Society and of APA's Division 5, and was one of the founders of the Southeastern Psychological Association. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

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Reports 3 studies that used a total of 195 male and female undergraduates. Exp I showed that shifts in attitude were accompanied by shifts in the recall of the more qualitative rather than quantitative aspects of past behaviors. Exps II and III assessed the effects of recall on Ss' commitment to newly formed attitudes. On the premise that behavior recall is biased so as to be consistent with salient attitudes, it was hypothesized that recall would serve to increase Ss' commitment to their attitudes. In Exp II it was assumed that degree of commitment to an attitude would be reflected in the persistence of the attitude, behavioral intention, and actual behavior. As anticipated, Ss' intentions were more consistent with their attitudes when they had been prompted to recall attitudinally relevant behaviors. However, recall did not affect attitude persistence or actual behavior. In Exp III, commitment was measured by resistance to an attack on an attitude. Ss were more likely to maintain an attitude in the face of an attack if they had been induced to recall attitudinally relevant behaviors. The data support the hypothesis that attitudes can affect recall, which in turn affects commitment to the attitudes. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Reciprocal relations between self-reported substance use and delinquency were examined through the analysis of 4-wave panel data collected from 1,218 high school students. A longitudinal, latent-variable framework was used to investigate interrelationships between changing patterns of generalized involvement in these 2 problem behaviors, while simultaneously accounting for specificity in drug use (e.g., marijuana use) and delinquency (e.g., theft). Analyses revealed that a model of bidirectional effects between polysubstance use and general delinquency was plausible for boys but not for girls. For boys, the effect of delinquency on substance use was small but consistent over time, whereas the effect of substance use on delinquency was larger but restricted to the earlier waves of the study. Implications for the question of whether or not substance use and delinquency have causal connections are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The primary objective of this investigation was to study the effect of D-alpha-tocopherol acid succinate (vitamin E succinate) and prostaglandin E2 (PGE2), individually and in combination, on the proliferation of human tongue squamous carcinoma cells (SCC-25) in vitro. Test compounds in varying concentrations were incubated with cells in serum-free Dulbecco's Modified Eagle's Medium-Ham's F-12 Medium (50:50), supplemented with 0.1% albumin for sixteen hours. Cell proliferation was measured by the incorporation of [3H] thymidine in acid-insoluble material (i.e. DNA). Prostaglandin E2 and vitamin E succinate, individually at 10(-9)-10(-6) M, caused significant dose-dependent inhibition in DNA synthesis. A combined dose of each compound at 10(-5) M resulted in significant additive inhibition which averaged 43.53% (p < 0.005). Addition of indomethacin (INDO) to cell cultures induced significant dose-dependent stimulation in DNA synthesis. Hence, we might suggest that the overall potential of vitamin E in controlling malignant cell proliferation in vivo could be due to its own effect combined with that of endogenous PGs which are normally produced in excessive amounts by malignant cells.  相似文献   

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Memorializes D. E. Super, who prompted vocational psychologists to expand the study of how people choose occupations to include how individuals develop careers. He formulated a life-stage model that conceptually explicated and operationally defined the developmental tasks and coping behaviors that foster occupational choice and vocational adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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