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Associations among dating, sexual activity, gender, and adjustment were investigated in 2,273 Italian adolescents (54% female, ages 14 to 19 years) attending public high schools. After controlling for age and type of school attended, both being in a dating relationship and being male were associated with less alienation, more positive views of the self, and higher general expectations for success. Sexual activity interacted with both gender and dating status in predicting feelings of depression. For boys, there were no differences between youth who were sexually active and youth who were not; however, sexually active girls had higher levels of depressive symptoms than girls who were not sexually active. Among youth who were not sexually active, there were small differences between daters and nondaters; among sexually active youth, daters had lower levels of depression than nondaters. Gender differences in adolescents' experience of dating and sexual relationships and implications for adjustment are discussed.  相似文献   
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With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased.  相似文献   
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The role of the clinical nurse specialist (CNS) is multidimensional. Although clinical expertise is the central core of the CNS role, the aspect of leadership is pivotal to effecting change in practice. Recently, the National Association of Clinical Nurse Specialists has redefined the role by spheres of influence and core competencies. Still, clinical expertise is central. This article highlights challenges as well as rewards in the CNS role. In addition, an example of entrepreneurial endeavors for the CNS is presented.  相似文献   
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OBJECTIVE: This study assessed the feasibility and efficacy of a parent-education group for families with young children and a parent with depression. We designed the program to be readily disseminated if shown to be effective. METHOD: We recruited 44 parents with depression from clinics and family doctors in Hamilton, Ontario, and randomly assigned them to receive the parenting program or to a wait-list control group. The outcomes measured included knowledge of depression, parenting, family relationships, depression symptoms, child depressive symptoms, and functioning. We used analysis of covariance to test for posttreatment differences between experimental and control groups. RESULTS: Of the treatment group, 27% dropped out at posttreatment, and 43% by follow-up. Those who dropped out had more severe depression at baseline than did those who completed the program, and there was selective loss of parents with more severe depression in the experimental group. In intention-to-treat analyses at posttreatment, probands in the experimental group reported more improvements on family functioning, parenting sense of competence, and family and parent conflict than did control subjects. Standardized effect sizes (ES) were medium (0.4 to 0.6). When baseline depressive symptom scores were controlled in the analyses, the between-group differences were reduced, showing that selective loss of participants may have influenced the findings. CONCLUSIONS: On balance, the results are encouraging and support the further development and evaluation of the group intervention. However, the study does not provide unequivocal evidence in support of the program. Before it is transferred to other settings, the program needs further modification to improve participation by parents with more severe depression and further evaluation of its effectiveness.  相似文献   
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Previous mouse liver studies with diazepam (DZ),N-desmethyldiazepam (NZ), and temazepam (TZ) confirmed that under first-order conditions, DZ formed NZ and TZ in parallel. Oxazepam (OZ) was generatedvia NZ and not TZ despite that preformed NZ and TZ were both capable of forming OZ. In the present studies, the concentration-dependent sequential metabolism of DZ was studied in perfused mouse livers and microsomes, with the aim of distinguishing the relative importance of NZ and TZ as precusors of OZ. In microsomal studies, theK ms andV maxs, corrected for binding to microsomal proteins, were 34 μM and 3.6 nmole/min per mg and 239 μM and 18 nmole/min per mg, respectively, forN-demthylation andC 3-hydroxylation of DZ. TheK ms andV maxs forN-demethylation andC 3-hydroxylation of TZ and NZ, respectively, to form OZ, were 58 μM and 2.5 nmole/min per mg and 311 μM and 2 nmole/min per mg, respectively. The constants suggest that at low DZ concentrations, NZ formation predominates and is a major source of OZ, whereas at higher DZ concentrations, TZ is the important source of OZ. In livers perfused with DZ at input concentrations of 13 to 35 μM, the extraction ratio of DZ (E{DZ}) decreased from 0.83 to 0.60. NZ was the major metabolite formed although its appearance was less than proportionate with increasing DZ input concentration. By contrast, the formation of TZ increased disporportionately with increasing DZ concentration, whereas that for OZ decreased and paralleled the behavior of NZ. Computer simulations based on a tubular flow model and thein vitro enzymatic parameters provided a poorin vitro-organ correlation. TheE{DZ}, appearance rates of the metabolites, and the extraction ratio of formed NZ (E{NZ, DZ}) were poorly predicted; TZ was incorrectly identified as the major precursor of OZ. Simulations with optimized parameters imporved the correlations and identified NZ as the major contributor of OZ. Saturation of DZN-demethylation at higher DZ concentrations increased the role of TZ in the formation of OZ. The poor aqueous solubility (limiting the concentration range of substrates usedin vitro), avid tissue binding and the coupling of enzymatic reactions in liver, favoring sequential metabolism, are possible explanations for the poorin vitro-organ correlation. This work emphasizes the complexity of the hepatic intracellular milieu for drug metabolism and the need for additional modeling efforts to adequately describe metabolite kinetics. This work was supported by the Medical Research Council of Canada (MA-9104).  相似文献   
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