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991.
We examined a random sample (N=3606) of undergraduates at one large midwestern university and explored correlates of ecstasy use and how use varied by gender, race, and sexual identity. Approximately 10% of the sample used ecstasy in their lifetime; 7% had used within the past year and 3% within the past month. Ecstasy was the second most likely illicit drug to be used, marijuana being the first. Multivariate logistic regression indicated that while men and women were equally likely to have used ecstasy, excessive partying, sexual identity, and grade point average were strongly correlated with ecstasy use. After adjusting for several factors, the number of sexual partners increased the likelihood of ecstasy use, as did self-reported sexual identity; gay, lesbian, and bisexual students were more than two times as likely to have used ecstasy in the past year. Significant relationships existed between ecstasy use and other substance use such as binge drinking, marijuana use, and cigarette smoking. Implications for interventions are discussed. 相似文献
992.
In vitro activity of gemifloxacin against clinical isolates of Neisseria gonorrhoeae with and without mutations in the gyrA gene 总被引:1,自引:0,他引:1
Ruiz J Marco F Sierra JM Aguilar L Garcia-Mendez E Mensa J Jiménez De Anta MT Vila J 《International journal of antimicrobial agents》2003,22(1):73-76
The MIC of gemifloxacin and five other quinolones was tested against 31 clinical isolates of Neisseria gonorrhoeae; strains were analyzed for the presence of mutations in both the gyrA and parC genes. Only seven strains were resistant to nalidixic acid due to a mutation in the gyrA gene but not in the parC gene, with six and two considered intermediate to ciprofloxacin and levofloxacin, respectively. The activity of gemifloxacin was similar to that of trovafloxacin and moxifloxacin, but was more active than nalidixic acid, ciprofloxacin or levofloxacin against the gyrA mutant strains. Gemifloxacin is a valid therapeutic alternative to treat infections with N. gonorrhoeae, retaining its activity against strains already presenting a mutation in gyrA. 相似文献
993.
Graded doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were added to primary hepatocyte cultures of bald eagle (Haliaeetus leucocephalus) embryos to determine their sensitivity to induction of cytochrome P4501A (CYP1A) and porphyrin accumulation. No porphyrin accumulation was observed, but both CYP1A catalytic activity (using the ethoxyresorufin-O-deethylase (EROD) assay) and immunodetectable CYP1A were induced by relatively high concentrations of TCDD. Bald eagle hepatocytes were less sensitive to CYP1A induction than hepatocytes from any other avian species that we have studied to date. These in vitro results are in general agreement with recent assessments of field data, which indicate that bald eagles are relatively insensitive to some of the effects of TCDD and related compounds. Preparation of bald eagle hepatocytes was challenging because existing methods did not yield monolayers of cells. Here we describe details of a new method that was successful for bald eagle hepatocytes. This new method is used routinely in our laboratory to prepare hepatocyte cultures from birds for examination of various biochemical responses to environmental contaminants. 相似文献
994.
Patients who have undergone orthopaedic surgery represent a high-risk group for venous thromboembolism (VTE). Despite the routine prophylactic use of antithrombotic agents, patients still experience thrombotic events that can result in mortality and acute morbidity and, in significant numbers of patients, may lead to long-term consequences such as the post-thrombotic syndrome. Increasingly, initial VTE events occur after hospital discharge since the length of stay in hospital after major orthopaedic surgery has decreased in many countries. There is a need for further improvement in the prevention of VTE. As well as undergoing extensive safety and efficacy studies for registration purposes, new prophylactic strategies need to be evaluated from a pharmacoeconomic perspective to help guide their introduction into routine clinical practice. Over the past 15 years a number of pharmacoeconomic evaluation studies of VTE prophylaxis have been carried out in orthopaedic patients, most of which evaluated short-term clinical endpoints. During the same period, improvements in our understanding of the natural history of VTE as well as the emergence of new treatments have led to changes in the management of patients with, or at risk of, VTE. The aim of this paper was to address how best to conduct pharmacoeconomic analyses of new antithrombotic agents in light of changes in practice patterns for orthopaedic patients and greater understanding of the disease process. We put forward recommendations for relevant outcome measures, timeframes, endpoints and epidemiologic data sources. We also suggest a structure for a pharmacoeconomic model. In this model, the outcomes and costs of VTE-related care during both the acute and chronic phases of the disease are incorporated. Symptomatic deep vein thrombosis and pulmonary embolism, recurrent VTE, post-thrombotic syndrome, major hemorrhage and all-cause death are included. We also recommend that the relevance of quality-adjusted survival is investigated, and that economic appraisals are presented in both cost-consequence and budget-impact approaches. These recommendations are based on extensive examination of recent advances in the management of VTE combined with a greater understanding of its natural history. 相似文献
995.
New chemical entities are routinely screened in vitro and in vivo for their ability to induce cytochrome P450s (CYP), other drug-metabolizing enzymes and possibly transporters in an attempt to more accurately predict clinical parameters such as drug-drug interactions and clearance in humans. Some of these potential therapeutic agents can cause induction of the metabolism of another molecule or auto-induction thereby increasing their own metabolism and elimination, as well as potentially any molecules metabolized by the same enzyme(s). Key CYPs in the 1A, 2B, 2C, and 3A families have all been shown to be inducible. It would be clearly advantageous to know the potential for a compound to induce drug metabolizing enzymes or transporters prior to clinical development, and many in vitro systems have been developed for this purpose. Newer computational technologies are also being applied in order to attempt to predict induction from the molecular structure alone before a molecule is even synthesized or tested. This review will cover the various in vitro and in silico methods developed for prediction of key inducers of CYPs and other proteins, as well as the limitations of such technologies and applications in the future. 相似文献
996.
LXRs: new therapeutic targets in atherosclerosis? 总被引:6,自引:0,他引:6
The liver X receptors (LXRs) are nuclear receptors activated by oxysterols that are now recognized to play an important role in the control of lipid homeostasis. LXRs have been implicated in the regulation of cholesterol and fatty acid metabolism in multiple tissues, including liver and intestine, as well as in macrophages. The importance of these receptors in physiological lipid metabolism suggests that they may also influence the development of metabolic disorders such as hyperlipidemia and atherosclerosis. Strong support for this idea has been provided by recent studies that directly linked LXR activity to the pathogenesis of atherosclerosis. These observations identify the LXR pathway as an attractive target for intervention in cardiovascular disease. 相似文献
997.
PURPOSE: To evaluate ocular findings in hospitalized children with systemic Candida species infection. DESIGN: Retrospective review of inpatient hospital consultations. METHOD: Inpatient hospital consultations performed by a pediatric ophthalmology service over a 30-month period were reviewed. RESULTS: Of 600 consultations performed by the service, 30 were to rule out ocular findings in patients with suspected or known candida infection. No patients had ocular findings consistent with endophthalmitis or chorioretinitis. One patient had nonspecific findings of multisystem organ failure, and one had vascular findings secondary to elevated pulmonary venous pressures. CONCLUSIONS: In contrast to the results of studies performed 10 to 15 years ago, ocular involvement is highly unusual in children with candidemia, but such consultations account for a substantial workload. Further attention to risk factors associated with ocular infection is warranted. 相似文献
998.
Kent DL Fujii GY Pieramici DJ Reynolds SM Melia M Rossi JV Humayun MS Caffey S De Juan E 《Retina (Philadelphia, Pa.)》2003,23(2):152-158
PURPOSE: To review in a standardized fashion pre- and postoperative fluorescein angiographic characteristics in patients undergoing limited macular translocation (LMT) with scleral imbrication to treat subfoveal choroidal neovascularization (SFCNV) secondary to age-related macular degeneration (AMD). The current study was undertaken to assess any potential effects of the translocation procedure on altering the angiographic characteristics of SFCNV before laser photocoagulation. METHODS: A consecutive series of patients undergoing LMT for AMD was identified retrospectively. The pre- and postoperative fluorescein angiograms were reviewed in a masked fashion. Angiographic characteristics evaluated included pre- and postoperative lesion components, stability of lesion, and the amount of retinal translocation obtained. RESULTS: Eighty-eight patients (90 eyes) had angiograms of adequate quality to permit evaluation. Time between the preoperative and the prelaser angiogram ranged from 2 to 84 days (median 7.5 days). Neovascular complexes remained unchanged or decreased in size in 79% of patients. There was no statistically significant difference in lesion size between the pre- and postoperative periods (P = 0.34). Retinal movement ranged from 160 microm to 3,320 microm (median 960 microm), with 61% of cases undergoing effective translocation (i.e., the fovea was moved away from the neovascular complex). None of the lesion components or demographic factors evaluated affected the amount of translocation obtained. Larger lesions were more likely to remain subfoveal following translocation (P = 0.004). CONCLUSION: The size and lesion characteristics appear relatively stable following translocation. Amount of retinal movement is not associated with angiographic lesion characteristics. Only size was associated with achievement of desired translocation in the final model, with large lesions being less likely to achieve desired translocation. In our study group, the amount of retinal translocation was variable with 61% of cases undergoing effective translocation. 相似文献
999.
Acute macular neuroretinopathy (AMNR) is a rare condition that produces transient or permanent visual impairment. Typical cases have acute onset multifocal scotomas that correspond rather precisely with reddish, flat, or depressed circumscribed lesions in the macula. These lesions are wedge-shaped and generally point toward the fovea. The pathophysiology of AMNR is unclear, the causes are uncertain, and there is no specific treatment for this condition. This review summarizes the presentation, possible risk factors, and prognosis of the 41 cases of AMNR reported in the published, English-language literature from 1975 through April 2002. Possible areas for future research into the etiology of this rare condition are discussed. 相似文献
1000.