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1.
Abstract: The current study examined the extent to which mothers, fathers, teachers, and teenage friends influenced Latino adolescents’ academic motivation. Using path analysis, separate models were tested for 154 Latino boys and 156 Latina girls. Findings indicated that mothers’ and teachers’ academic support were positively related to adolescent girls’ academic motivation, and fathers’ and teachers’ academic support were positively related to adolescent boys’ academic motivation. The salience of teachers’ support, possible reasons for gender differences, and implications for future research are discussed.  相似文献   
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A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.  相似文献   
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SKIN FERMENTS     
That a definite change in the reactivity of the skin takes place during the transition from infancy to childhood has been repeatedly noted. Rolly (5), working with a variety of bacterial toxins, found that infants did not react, but that reactions occurred with advancing age. Similarly Tenner (6), using Witte''s peptone, colon bacilli, and tuberculin observed that at about the period that the skin of children became increasingly sensitive to tuberculin, a corresponding reactivity was manifest toward the other antigens. It seems possible to us that this phenomenon is related to the alteration in the ferments of the skin that takes place during the transition period. Thus while the protease of the adult type of skin causes a definite autolysis, that of the fetal skin does not, the synthetic potential evidently predominating. Of greater significance seems to be the fact that the skin of the young animal contains peptidase to a considerable amount, while the adult skin seems to be without this ferment activity. If we assume that the disintegration of the native protein of the antigen is essential in eliciting certain skin tests, it would seem probable that the splitting would be less apt to take place in the young skin in which the lytic effects of the ferments are relatively suppressed. On the other hand, the young skin, containing peptidase, would be able to digest rapidly any antigen consisting of partially hydrolyzed proteins—as tuberculin—and in this way detoxicate and remove the noxious material. From these considerations the undoubted alteration of the skin reactivity taking place after infancy seems definitely correlated with changes in the proteolytic ferments. In how far they enter into and alter the specific reactions cannot be determined from the limited data so far available. Of the other ferments, the lipases, as pointed out by Porter, are possibly of importance in the resistance of the skin to tuberculous infection. It will be observed from the table that the activity of these skin ferments is less manifest in their action as esterases, on ethyl butyrate, than on the neutral fats used, oleic oil and butter fat, in this way differing from the activity of the serum. The relative resistance of the skin to tuberculous infection can, however, hardly be due to the activity of the lipase alone, for it must be kept in mind that the lepra bacillus, also rich in lipoids, is enabled to proliferate well within the epithelial tissues.  相似文献   
8.
Recent reports of sexually transmitted infection-rate increases among men indicate the need for renewed study of male sexual risk behavior to aid development of updated and novel risk reduction interventions. Men who have childhood sexual abuse (CSA) histories consistently report frequent sexual risk behavior. The objective of this sturdy is to explore whether posttraumatic stress disorder (PTSD) and depression are moderators and/or mediators of the association between CSA and sexual risk in adult men. A cross-sectional survey study employing random digit dial recruitment was administered to men aged 18–49 years from Philadelphia County. Two bundred ninety eight men were recruited and screened for CSA history, administered items from the Posttraumatic Stress Diagnostic Scale (PDS) and Center for Epidemiologic Studies—Depression (CES-D), and asked to estimate their number of lifetime sexual partners (LSPs). Effects of sociodemographic characteristics, CSA, PTSD, and depression on the number of LSPs were modeled using Poisson regression. Results show that 197 (66%) men participated; 43 (22%) had CSA histories. CSA was significantly associated with PTSD/depression (P=.03). Four sociodemographic variables (age, race, sexual identity, and education), CSA (incidence rate ratio, IRR=1.47, P<.001), PTSD (IRR=1.19, P=.04), depression (IRR=1.29, P=.001), all 2-way interactions, and the 3-way CSA/PTSD/depression interaction (IRR=11.00, P<.001) were associated with the number of LSPs (R2=0.27). In conclusion, sexual partnership patterns unique to men with CSA histories and comorbid PTSD/depression appear to lead to substantially higher numbers of LSPs. Estimates of this relationship may have been biased toward the null by underreporting that can occur with phone surveys. Cross-sectional studies do not support causal inferences; however, the identification of a moderating and mediating influence of PTSD/depression on the relationship between CSA and sexual risk behavior is important and suggests the need for future studies with larger samples that examine trajectories for CSA, psychiatric illness, and sexual partnerships.  相似文献   
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The solitary fibrous tumor (SFT) is a very rare and usually benign neoplasm. This tumor is mostly located in the thoracic cavity, but it has also been reported in numerous sites including liver, skin, and meninges. Due to its rarity diagnosis is often difficult. Accordingly, histopathological differentiation is of major importance. Solitary fibrous tumors consistently express CD 34 and react negatively to epithelial markers. This absence of expression of epithelial markers, especially cytokeratin, is also useful to distinguish these rare entities from sarcomatous mesotheliomas. The treatment of choice for solitary fibrous tumors is extensive surgical resection. Up to now there is no evidence that radiation and chemotherapy are effective. The local recurrence or onset of metastases depends on histologic parameters. In cases of benign classification (60-80%), the recurrence rate was only 2% after surgical excision. One-half of the patients with malignant tumors can be cured; the rest develop recurrences and metastases more often. Especially in those cases, emphasis should be placed on continual follow-up examination. We report two cases of a 65- and a 75-year-old male patient with huge intrathoracic solitary fibrous subpleural tumors, discovered incidentally on routine chest X-ray.  相似文献   
10.
Eighty-two patients (median age, 51 years; range, 27-87 years) with refractory gastroesophageal reflux disease (GERD) underwent floppy Nissen/Rossetti fundoplication during the period 1980 to 1990. The median postoperative hospital stay was 5 days (3-16). Median follow-up was 72 months and included endoscopy and a clinical and a questionnaire assessment. Subjective symptoms of reflux were abolished in 98%, and 96% of the patients were satisfied with the results. Endoscopy showed healing of the esophagitis in 98%. There had been no disruption of the fundoplication. Twenty patients complained of gaseous distention and increased flatulence; only two of them had severe problems. Three patients were unable to belch. In conclusion, the floppy fundoplication has been an effective operation with no deaths, a low incidence of morbidity and adverse side effects, and without a tendency for late failure.  相似文献   
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