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951.
This study examines predictors of alcohol use disorders (AUDs) among an urban American Indian cohort who were followed from approximately age 11 to age 20. Approximately 27% of the sample had a lifetime diagnosis of alcohol abuse or dependence. The results indicated that externalizing, but not internalizing, behaviors, family conflict, and school liking served as significant predictors of an AUD. Neither having an alcoholic mother nor an alcoholic father was found to be significantly predictive of an alcohol use disorder at ages 19 and 20. Finally, early alcohol initiation was a substantial predictor of an AUD and acted as a partial mediator.  相似文献   
952.
BACKGROUND: African Americans (AAs) have a higher prevalence of obesity and type 2 diabetes than do whites. Higher insulin resistance and hyperinsulinemia have been reported in adult AAs than in whites. Differences in adipose tissue and its distribution may account for these findings. OBJECTIVE: The objective was to ascertain whether differences between AA and white women in adipose tissue (AT) and skeletal muscle (SM) volumes account for ethnic differences in insulin resistance. DESIGN: We used whole-body magnetic resonance imaging to measure AT and SM volumes and used the intravenous-glucose-tolerance test to measure insulin resistance. RESULTS: AAs (n = 32) were 29-42% more insulin resistant than were whites (n = 28) after adjustment for weight and height or any AT volumes (P < 0.05). After adjustment for SM volume, the difference decreased to 19% and became nonsignificant. AAs had a 163% greater acute insulin response to glucose than did whites; this difference was significant even after adjustment for insulin sensivitity index, weight, height, and any magnetic resonance imaging measures. With respect to regional AT volumes, an association independent of race, weight, height, and SM volume was found only between increased intermuscular AT and lower insulin sensitivity index. CONCLUSIONS: Premenopausal AA women had significantly higher insulin resistance and acute insulin response to glucose than did their white counterparts. Whereas the difference in insulin resistance was partially accounted for by a greater SM volume in the AAs than in the whites, the difference in the acute insulin response to glucose was independent of any AT and SM measures and was disproportionately larger than expected according to the difference in insulin resistance. In addition, whole-body intermuscular AT was an important independent correlate of insulin resistance.  相似文献   
953.
The dose emitted from dry powder inhalers may be inhalation flow-dependent. Using an ex vivo method, the Electronic Lung, we have measured the aerodynamic characteristics of the emitted dose for both active constituents from Seretide Diskus (salmeterol xinafoate 50 mcg; fluticasone propionate 500 mcg) and Symbicort Turbuhaler (formoterol 6 mcg; budesonide 200 mcg). Electronic inhalation profiles were collected from 20 severe asthmatics (mean PEFR 53% predicted) when they inhaled using a placebo Seretide Diskus and a placebo Symbicort Turbuhaler. These were replayed in the Electronic Lung with the respective active inhaler in situ. Mean(S.D.) peak inhalation flow rates (PIFR) through the Diskus and Turbuhaler were 94.7(32.9) and 76.8(26.2) l min(-1), respectively. From the Electronic Lung the Diskus inhalation profiles provided a mean(S.D.) fine particle dose (FPD) for fluticasone propionate and salmeterol of 20.4(4.8) and 18.4(4.4)% labelled dose. For Turbuhaler inhalation profiles the FPD was 23.1(12.9) and 20.7(11.1)% labelled dose for budesonide and formoterol, respectively. The linear (p < 0.001) relationships between FPD against PIFR for budesonide and formoterol were 3 (p = 0.002) and 2.8 (p = 0.007) times steeper than fluticasone propionate and salmeterol, respectively. The results highlight a more significant effect of inspiratory flow on variable dosage emission when using the Symbicort Turbuhaler compared with the Seretide Diskus.  相似文献   
954.
Cytokine profiles during cowpox and vaccinia (WR strain) virus infections were characterized in intranasal (i.n.) and intraperitoneal (i.p.) models in BALB/c mice. The time-course of induction and effects of cidofovir treatment on interferon (IFN)-gamma, IFN-gamma inducible protein (IP)-10, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 were determined. The four mouse infection models have distinct patterns of cytokine induction. Cowpox virus i.p. and vaccinia virus i.n. infections showed increased induction throughout the time studied. Cowpox virus i.n. infection resulted in delayed induction of IFN-gamma and IP-10. Cytokine levels were fairly constant during vaccinia virus i.p. infections. Cidofovir treatment (100mg/kg/day i.p. for 2 days) significantly suppressed certain cytokine (IFN- gamma, IL-6, IL-10, IL-11, IP-10, LIF, MCP-1, MCP-3, MCP-5, MIP-1 gamma, and TIMP-1) levels to near normal relative to uninfected animals, as well as prevented mortality and reduced virus titers significantly. Characterization of cytokine responses has implications for understanding the immune responses and pathogeneses of viral infections in these mouse models.  相似文献   
955.
Summary This phase II trial was initiated to assess the efficacy and safety of oral vorinostat (Zolinza™, suberoylanilide hydroxamic acid, SAHA) in patients with recurrent and/or metastatic head and neck cancer. Eligible patients must have recurrent and/or metastatic head and neck cancer unresponsive to or intolerant of conventional chemotherapy. Patients must have measurable disease, adequate hematologic, hepatic, and renal function, and be able to swallow capsules. Four or more weeks must have elapsed since prior chemotherapy, radiation therapy, major surgery or investigational anticancer therapy, and patients must have recovered from prior toxicities. Study endpoints included response rate, duration of stable disease and progression-free survival. Thirteen patients were enrolled (9 males); 1 withdrew consent prior to starting therapy. Twelve patients received oral vorinostat 400 mg once daily and were evaluable for response. The median age was 54 years (range 40–82). All patients had received prior chemotherapy (including 10 with platinum- or taxane-based combination therapy), and 9 had prior radiation therapy. No confirmed partial or complete responses were observed. One unconfirmed partial response was seen. Three patients had stable disease ranging from 9 to 26 weeks. Nine patients discontinued due to progressive disease, two withdrew consent, and one discontinued therapy for grade 3 anorexia. Grades 3–4 drug-related toxicities included thrombocytopenia (n = 3), anorexia (n = 2), and dehydration (n = 2). Oral vorinostat 400 mg qd was generally well tolerated but did not demonstrate efficacy as defined by tumor response in this small group of heavily pre-treated patients. Presented in part as a poster at the 40th Annual Meeting of the American Society of Clinical Oncology, New Orleans, LA, June 5–8, 2004. This research has not been published elsewhere and has not been submitted simultaneously for publication elsewhere.  相似文献   
956.
Needle and syringe sharing is common among people who inject drugs and so is unprotected sex, which consequently puts their sex partners at risk of sexually transmitted infections (STIs) including HIV and other blood-borne infections, like hepatitis. We undertook a nested study with the regular female partners of men who inject drugs participating in a longitudinal HIV incidence study in Delhi, India. In-depth interviews were conducted with female partners of 32 men. The interviews aimed to gather focused and contextual knowledge of determinants of safe sex and reproductive health needs of these women. Information obtained through interviews was triangulated and linked to the baseline behavioural data of their partner (index men who injected drugs). The study findings illustrate that women in monogamous relationships have a low perception of STI- and HIV-related risk. Additionally, lack of awareness about hepatitis B and C is a cause of concern. Findings also suggest impact of male drug use on the fertility of the female partner. It is critical to empower regular female partners to build their self-risk assessment skills and self-efficacy to negotiate condom use. Future work must explore the role of drug abuse among men who inject drugs in predicting fertility and reproductive morbidity among their female partners.  相似文献   
957.

Purpose  

This study aimed to determine incidence rates of novel influenza A (H1N1) infection among healthcare personnel with different exposure risks during the 2009 H1N1 pandemic.  相似文献   
958.
Human campylobacteriosis is currently the most common cause of acute bacterial gastroenteritis on the island of Ireland, accounting for over 3,000 laboratory reports per year, where circa 2,000 reports originate from the Republic of Ireland and circa 1,000 reports from Northern Ireland. Elsewhere, consumption of contaminated poultry has been associated with the zoonotic transmission of disease, therefore it was the aim of this study to examine the phenotypic and genotypic relatedness of campylobacters isolated from chickens and humans locally. Sixty isolates were subtyped using phenotyping techniques (biotyping, phage-typing), as well as genotyping techniques (multilocus enzyme electrophoresis (MEE), ribotyping) and the data compared. The frequency of shared phenotypes and genotypes between poultry and humans varied depending on the typing technique employed ranging from 98.2% of human isolates sharing a similar resistotyping (MAST) disc type with poultry strains to 20% similarity with MEE typing. Overall, this small study is the first report on phenotypic and genotypic relatedness between human and poultry campylobacters in Northern Ireland, isolated under controlled conditions. The study demonstrated an association between chicken and human sub-species types, taken from a relatively contained epidemiological environment. Further work is required with larger numbers of isolates coupled with typing schemes, which are able to reliably cluster strains from chicken and humans, which share high degrees of clonality, before local poultry can be conclusively proven to be a significant source of human campylobacteriosis.  相似文献   
959.
Mice were intranasally immunised with a mixture of Bordetella pertussis filamentous haemagglutinin (FHA) and recombinant pertussis toxin, PT-9K/129G (rPT) in combination with chitosan. For both antigens, this formulation induced systemic responses as measured by serum IgG and also mucosal responses as measured by secretory IgA in lung lavage and nasal washes. Immunosorbant assays were used to measure these responses. Both the systemic and mucosal responses were considerably higher than those produced when a mixture of rPT and FHA was administered nasally without chitosan. In comparison, intraperitoneally administered rPT/FHA adsorbed to Alhydrogel elicited only a systemic response, and nasal chitosan solution produced neither systemic nor mucosal response. This study clearly demonstrated that chitosan potentiated the serum and mucosal immune responses to nasally administered FHA and rPT in mice. Hence, this nasal chitosan delivery system has potential as a new non-injectable vaccine for the prophylaxis of whooping cough.  相似文献   
960.
Mode of action (MOA) information is increasingly being applied in human health risk assessment. The MOA can inform issues such as the relevance of observed effects in laboratory animals to humans, and the variability of response within the human population. Several collaborative groups have developed frameworks for analyzing and utilizing MOA information in human health risk assessment of environmental carcinogens and toxins, including the International Programme on Chemical Safety, International Life Sciences Institute, and U.S. Environmental Protection Agency. With the goal of identifying gaps and opportunities for progress, we critically evaluate several of these MOA frameworks. Despite continued improvement in incorporating biological data in human health risk assessment, several notable challenges remain. These include articulation of the significant role of scientific judgment in establishing an MOA and its relevance to humans. In addition, binary (yes/no) decisions can inappropriately exclude consideration of data that may nonetheless be informative to the overall assessment of risk. Indeed, the frameworks lack a broad consideration of known causes of human disease and the potential for chemical effects to act additively with these as well as endogenous background processes. No integrated analysis of the impact of multiple MOAs over the same dose range, or of varying MOAs at different life stages, is included. Separate consideration of each MOA and outcome limits understanding of how multiple metabolites, modes, and toxicity pathways contribute to the toxicological profile of the chemical. An extension of the analyses across outcomes with common modes is also needed.  相似文献   
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