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Attachment style, childhood adversity, and behavioral risk among young men who have sex with men. 总被引:2,自引:0,他引:2
Marya Viorst Gwadz Michael C Clatts Noelle R Leonard Lloyd Goldsamt 《The Journal of adolescent health》2004,34(5):402-413
PURPOSE: To examine relationships among childhood adversity, attachment style (one's core beliefs regarding the self and others), and the following risk behaviors and contexts among young men who have sex with men (YMSM): homelessness, daily substance use, participation in sex work, involvement in the criminal justice system, and being out of school or work. METHODS: Using a targeted sampling approach, we recruited 569 YMSM aged 17-28 years from natural venues in New York City including bars, clubs, parks, and bus stations. Youth completed a structured interview assessing lifetime and current risk and protective contexts and behavior. Data were analyzed using univariate and multivariate statistical methods, including hierarchical logistic regression. RESULTS: After controlling for demographic characteristics and childhood adversity, YMSM with a fearful attachment style were more likely to have been homeless (OR 2.93, 95% CI 1.65-5.18), to have participated in sex work (OR 2.35, 95% CI 1.44-3.85), to use substances daily (OR 2.79, 95% CI 1.29-6.03), to have been involved in the criminal justice system (OR 2.04, 95% CI 1.38-3.01), and to be out of school/work (OR 2.47, 95% CI 1.47-4.15). Three subgroups were particularly vulnerable: YMSM who identified as heterosexual, or bisexual, and/or transgender. CONCLUSIONS: A fearful attachment style contributes to some YMSM remaining outside of the protective systems of family, school, and work, and is associated with risky contexts where they are less likely to encounter prosocial peers and adults. Further, it is associated with risk behavior. Although gay-identified youth are generally found to have poor outcomes when compared with the general population of adolescents, in the present report, YMSM who identified as heterosexual were at particular risk. Attachment theory can guide interventions by informing how individuals experience relationships and manage developmental transitions. 相似文献
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Nutritional deprivation is associated with poor growth and decreased levels of net circulating somatomedin activity, as measured by bioassay. Since somatomedin activity reflects the contributions both of somatomedins (which stimulate cartilage) and of somatomedin inhibitors (which antagonize the ability of the somatomedins to stimulate cartilage), we asked if changes in net somatomedin activity could involve progressive underlying alterations in levels of both somatomedins and somatomedin inhibitors. Groups of rats were killed during three days of fasting and 24 hours of refeeding. Fasting was associated with a rise in serum beta-hydroxybutyrate from 1.6 to 12.6 mmol/L after one day, followed by a decline to 4 mmol/L at three days. Somatomedins (low-MW) were separated from somatomedin inhibitors (high-MW) by gel permeation chromatography at acid pH on Sephadex G-50 and TSK-2000 HPLC. Somatomedins fell 35% after one day of fasting, and decreased to 59% below control levels after three days (P less than .05). Somatomedins did not change with six hours of refeeding, but then rose rapidly, reaching control levels after 24 hours. Somatomedins were correlated with change in weight (r = .41, P less than .05), but not with glucose or beta-hydroxybutyrate. Inhibitors rose to 195% above control-levels after one day of fasting, and continued to rise to 375% above control after three days (P less than .01). In contrast to the delayed change in somatomedins with refeeding, there was an abrupt fall in inhibitors (41% below three-day fasted levels after six hours), returning to control levels after 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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The risk of americium-induced liver cancer in beagle dogs that received long-term dietary ethanol was two to three times that of their nonalcoholic cohorts, even though the radionuclide retention time in hepatic tissue was shortened by the alcohol treatment. Liver malignancies did not occur in the ethanol-treated, nonirradiated controls. An ethanol-induced tumor-promoting effect was not observed in organs or tissues other than the liver. 相似文献
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Somatostatinomas, PPomas, neurotensinomas 总被引:2,自引:0,他引:2
We have reviewed data pertinent to three tumor syndromes that derive from overproduction of three GEP peptide hormones. The clinical syndrome of somatostatin excess remains well defined with diabetes, diarrhea, steatorrhea being predominant features. With the availability of assays and increasing awareness, more cases are being diagnosed in the intestine and these differ somewhat in their presentation with cholecystitis, GI bleeding, or a mass as the cardinal features. An unusual association with MEN II pheochromacytoma and neurofibromatosis is emerging. PPomas remain enigmatic. Although diarrhea is a feature, these tumors are usually silent and present with hypatomegally, abdominal pain, and jaundice because of the large size and malignant nature. Neurotensinomas remain rare and truly difficult to separate from the symptom complex produced by VIP excess. Edema, hypotension, cyanosis and flushing should alert one to the possibility of a neurotensin-secreting tumor. 相似文献
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A W Lloyd J A Baker G Smith C J Olliff K J Rutt 《The Journal of pharmacy and pharmacology》1992,44(6):507-511
Glycinebetaine has previously been shown to be effective at reducing leakage from liposomes which are frozen then thawed. This study involved the preparation of a series of N-modified betaines and the comparison of their cryoprotective activities with those of glycine, sarcosine, N,N-dimethylglycine and glycinebetaine. All the compounds investigated, with the exception of (dimethyloctylammonio)acetate, reduced the degree of leakage, after freezing and thawing, with additive concentrations up to 0.6 M. Reducing the degree of N-terminal methylation of glycinebetaine appeared to increase the leakage from liposomes at additive concentrations between 0.2 and 0.6 M. (Dimethylethylammonio)acetate, (dimethylisopropylammonio)acetate and (N,N,N',N'-tetramethylethylenediammonio)-N,N'-diacetate appeared to be no more effective than glycinebetaine, whereas improved protection was afforded by (triethylammonio)acetate and (diethylmethylammonio)acetate at most concentrations. This study demonstrates that the cryoprotective activity of glycinebetaine may be improved with modifications to the N-terminal. 相似文献
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We agree with many of the comments made by Yamada et al.,1namely that the ECG and NTproBNP are fundamental tests usedin the diagnosis of heart failure and that 相似文献
60.