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Aims : To describe, illustrate, and assess the reliability and construct validity of a method for assessing peer norms regarding drug use and selling. Design and participants : Face-to-face interviews of young adults (age 18-24) selected through multi-stage probability sampling in a low-income, high drug use, urban environment. Measurements : Subjects reported what proportion of their close friends actually encouraged them to use specific drugs, or would have objected to such use, currently and at age 15. Findings : Self-reports of peer norms are highly reliable, and have considerable construct validity in predicting drug behaviors. There is little encouragement of drug use, and substantial objection to use of drugs other than marijuana. While few subjects had many friends who encouraged them to sell drugs, about a third of the subjects said few if any of their friends would object to their selling drugs. Objection to drug use is more common, and encouragement of drug use less common, among women's peers than among men's peers. Conclusions : These items can be used to reliably and validly assess young adults' peer norms regarding drug use. Men and women report different peer norms.  相似文献   
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Aims To determine relationships between drug use ‘hardness’ (defined in increasing order of hardness as no drug use, marijuana use, non‐injected heroin or cocaine use, crack smoking and injection drug use) and prevalences of several sexually transmissible infections among young adults in a high‐risk neighbourhood. Drug users, particularly injection drug users and crack smokers, may be a core group for some sexually transmitted infections. Design Cross‐sectional survey and assays of young adults from (a) a household probability sample and (b) a targeted sample of youth who have used injected drugs, crack, other cocaine or heroin. Setting Bushwick, an impoverished New York City minority neighbourhood with major drug markets. Participants A total of 363 18–24‐year‐olds from a household probability sample; 165 Bushwick 18–24‐year‐olds who have used injected drugs, crack, other cocaine or heroin. Measurements Drug use by self‐report; serum‐ and urine‐based assays for HIV, hepatitis B and C, syphilis, gonorrhoea, chlamydia and herpes simplex (type 2). Findings Household‐sample prevalences: HIV, hepatitis C and syphilis, 1%; gonorrhoea 3%; chlamydia 5%; past or present hepatitis B infection 8%; herpes simplex (type 2) 18%. In combined household and targeted samples, hepatitis C and HIV were concentrated among drug injectors. Herpes simplex (type 2), syphilis and hepatitis B increased among women with ‘hardest drug ever used’. Conclusions Using ‘harder’ drugs is associated with some but not all of these infections. Prevention efforts should help youth avoid unsafe sex and higher‐risk drugs.  相似文献   
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Aims

Better understanding risk factors for metabolic syndrome (MetS) will allow early targeted intervention to mitigate long term risk. We aim to determine the disparate impact of each individual MetS component on overall risk of developing MetS, stratified by sex, race/ethnicity, and age.

Methods

Using data from the 2003–2014 National Health and Nutrition Examination Survey (NHANES), MetS prevalence among adults (age ≥18) was stratified by sex, race/ethnicity, age, and by individual MetS components (e.g. hypertension (HTN), diabetes mellitus (DM), waist circumference, serum high density lipoprotein (HDL), serum triglycerides (TG). Mutlivariate logistic regression models were used to evaluate the disparate impact of each risk factor on MetS risk.

Results

Overall MetS prevalence was 33.3%, with the highest prevalence among older individuals, among women, and among Hispanics. When stratified by each individual component of MetS, low serum HDL was the strongest predictor of MetS risk overall and among both men and women, among all race/ethnic groups, and among all age groups (overall: OR 20.1, 95% CI 18.6–21.7). While presence of DM also increased an individual’s risk of MetS, DM was the weakest predictor of MetS.

Conclusions

Among U.S. adults, low serum HDL carries the strongest risk in predicting development of MetS. This effect was seen among men and women, among all race/ethnic groups, and among all age groups, highlighting the importance of low serum HDL as a marker of MetS risk.  相似文献   
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目的 建立一种快速、灵敏的高效液相色谱-串联质谱(HPLC-MS/MS)方法以测定人血浆中对乙酰氨基酚浓度,并应用于两种对乙酰氨基酚制剂的人体药代动力学和生物等效性研究。方法 以替硝唑为内标,200μL血浆样品经5倍于其体积的乙酸乙酯液液萃取,再经Waters XBridge? C18柱等度洗脱分离后导入串联质谱,以正离子多反应监测模式进行定量分析,对乙酰氨基酚和内标的选择性反应离子对分别是m/z 152→110和248→121。方法经验证后应用于19名健康受试者单剂量空腹口服两种对乙酰氨基酚制剂500mg后药代动力学和生物等效性的研究。结果 血浆中对乙酰氨基酚在0.1~8.0 μg·mL-1范围内线性良好(r2 > 0.99),最低检测限为 0.1 μg·mL-1,提取回收率为91.0%~98.7%,日内和日间准确度分别为98.8%~111.3% (精密度:CV ? 9.03%)和94.9%~102.6% (精密度:CV ? 10.68%)。生物等效性试验中,受试制剂与参比制剂的主要药代动力学参数Cmax、AUC0-t和AUC0-∞ 几何均值比的90%置信区间分别为83.50%~105.79%,94.25%~101.54%和93.24%~101.02%,均落在生物等效可接受标准80.00%~125.00%范围内。结论 所建立测定人血浆中对乙酰氨基酚浓度的HPLC-MS/MS法具有快速灵敏、回收率高、选择性好的特点,适用于对乙酰氨基酚片人体药代动力学和生物等效性研究。受试制剂与参比制剂在人体内吸收速度和程度相似,两种制剂生物等效。  相似文献   
18.
Drug scene roles and HIV risk   总被引:1,自引:0,他引:1  
Aims. Drug scenes (social and spatial drug-using and drug-selling environments) have complex role structures. Many drug injectors earn money or drugs as drug or syringe sellers, hit doctors (people who help others to inject) commercial sex workers, or in other roles. This paper aims to measure "role behaviors" of drug injectors; describe which drug injectors are more likely to engage in such role behaviors; and to determine whether roles are related to elements of HIV risk . Design. Cross-sectional study of drug injectors . Setting. Bushwick, a section of Brooklyn, New York, a major location for injection drug use and drug sales . Participants. Seven hundred and sixty-seven street-recruited drug injectors . Measurements. Participants were interviewed about their roles, behaviors, socio-demographics and risk networks; sera were collected and assayed for HIV and hepatitis B core antibody . Findings. Socio-demographic variables are related to role-holding in complex ways. Economic need is generally associated with engaging in drug-scene role behaviors. Holders of these roles are at greater behavioral and network risk for HIV and other blood-borne infections than are other drug injectors. They also engage in extensive communication with other drug users, including discussion of HIV risk reduction . Conclusion. Role behaviors can be measured in quantitative studies, and seem to be related to HIV risk. Role-holders may be strategic targets for risk-reduction campaigns. It seems feasible and advisable to measure drug scene role-holding in research on drug users.  相似文献   
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BackgroundA growing body of findings illustrates the importance of state-dependency in studies using brain stimulation.ObjectiveWe aimed to investigate the effects of tDCS priming followed by rTMS applied over the right dorsolateral prefrontal cortex (DLPFC) on emotional working memory.MethodsIn a randomized single-blind within-subjects design, participants performed an emotional 3-back task at baseline and after tDCS priming (anodal, cathodal) and subsequent low-frequency rTMS (active, sham) of the right DLPFC. Stimuli consisted of words related to the distinct emotion categories fear and anger as well as neutral words.ResultsTask accuracy increased for fear-related words and decreased for neutral words across stimulation conditions. No general state-dependent effects of prefrontal rTMS on working memory were found. We further showed a detrimental effect of negative emotional content on working memory performance.ConclusionsOur findings support a hemispheric lateralization of emotion processing by demonstrating that the withdrawal-related emotion fear is associated with the right DLPFC and contribute to clarifying the interaction between working memory and emotion.  相似文献   
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