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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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The in vitro and in vivo functionality of Catapres-TTS, a transdermal therapeutic system that delivers the alpha adrenergic receptor agonist clonidine, is discussed in terms of the drug transport kinetics and resultant plasma drug concentration profiles. The design of Catapres-TTS is presented as an optimization by which the best combination of system performance characteristics is obtained within the inherent limitations of the transdermal drug transport properties and the known pharmacokinetic and pharmacodynamic properties of the drug. Clonidine is a potent antihypertensive agent with a relatively low therapeutic index. For Catapres-TTS, the majority of control over the drug input rate resides within the system, rather than within the skin, which significantly reduces the variability in drug input rate and resulting plasma drug concentration both within and between patients. Moreover, the presence of a rate-control element in the system allows for patterning of the drug release rate. An initial bolus of drug is placed in the contact adhesive layer, where its transport into the skin is not inhibited by the rate control element in the system, for reduction in the time needed to achieve steady state drug input. The selection of the loading dose of drug is described as an optimization between the minimization of the lag time and the maintenance of constant plasma drug concentrations during the crossover period between system applications in chronic therapy.  相似文献   
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Variation in opinions of medical experts is a problem for both the legal and medical profession. This is particularly relevant in breast imaging. BreastScreen Queensland and New South Wales have developed a review protocol to assess ‘reasonableness’ of radiological opinions. It is hoped that the protocol will be acceptable to the courts and will result in a fair outcome for all parties involved in a medico-legal dispute.  相似文献   
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Substance P and eledoisin stimulate the accumulation of inositol phosphates in a dose-dependent manner in retinal and superior colliculus slices of the rabbit. The EC50 values for substance P and eledoisin in both tissues were of the same order (1.5-4.9 microM), suggesting that the receptors in the two tissues were alike with characteristics of the SP-P subtype rather than the SP-E subtype. These data suggest that the SP-immunoreactive material in the retinal ganglion and amacrine cells is identical. The effectiveness for a number of tachykinin substances at 10(-5) M for stimulating inositol phosphates accumulation was as follows: Substance P greater than eledoisin greater than neurokinin A greater than neurokinin B greater than substance P (octapeptide) greater than substance P (pentapeptide). Spantide [(D-Arg1, D-Try7.9, Leu11) substance P] and (D-Pro2, D-Try7.9) substance P did not stimulate inositol phospholipid hydrolysis. However, spantide, at a concentration of 10(-6) M, was an antagonist of the effect produced by substance P, but had no action on the effect produced by neurokinin A or neurokinin B. Substance P and other tachykinins were also effective in stimulating inositol phosphates accumulation in 3-5-day-old rabbit retinal cultures but did not elicit a response in the older (25-30-day-old) cultures which lacked neurones but contained Müller cells. Furthermore, substance P was only active in the younger cultures in stimulating an increase in internal calcium levels. It is therefore concluded that retinal tachykinin receptors linked to phosphoinositide turnover and calcium mobilisation are associated exclusively with neurones and not with Müller cells.  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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