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991.
OBJECTIVES: The objective of this study was to assess the prevalence of binge drinking and its relation to other health behaviors, drinking-related attitudes and perceived social norms among German medical students. METHODS: 271 first-year German medical students completed a cross-sectional, self-administered survey. A total of 252 (62% female and 38% male) students provided useable surveys. The mean age was 20.6years (S.D.=1.7). RESULTS: Most students reported heavy drinking with 24% having one episode in the past 2 weeks (Infrequent Bingers) and 28% having two or more episodes (Frequent Bingers). Men were more likely than women to have had a binge drinking episode. Frequent binge drinkers saw more pros of drinking and reported a higher temptation to drink than students in the other groups. Additionally, they were more likely to smoke, use cannabis, not exercise and not eat fruits and vegetables. All students overestimated their peers' alcohol intake and binge drinking frequency. CONCLUSIONS: Binge drinking was highly prevalent in this sample and clearly related to other health risk behaviors. Drinking rates were similar to college students in other Western countries. Future research needs to assess the consequences of this multiple risk behavior among medical students regarding academic and professional performance as well as personal health.  相似文献   
992.
School-based smoking prevention programs are typically identical for all students. Tailoring prevention materials to focus on individual needs with an emphasis on students at highest risk is a promising alternative. Recent prevention programs have tailored materials based on the Stages of Acquisition, an extension of the Stages of Change used to tailor smoking cessation materials effectively for adults. Three stages of acquisition have been identified: Acquisition Precontemplation (aPC), Acquisition Contemplation (aC) and Acquisition Preparation (aPR). However, about 90% of nonsmoking adolescents classify themselves in the aPC stage. A cluster analysis was performed, using the Decisional Balance and Situational Temptations scales, for three random subsamples of adolescents within the aPC stage (N(1)=N(2)=N(3)=514). Four distinct subtypes were identified in each subsample: High Risk, Protected, Ambivalent, and Risk Denial. External validity was established using family support for nonsmoking, peer variables, and stage classification at follow-up assessment (12, 24, and 36 months). Family support for nonsmoking was related to subtype much more strongly than peer interactions. Subjects in the Protected subgroup were the most likely to remain in the aPC stage at each follow-up assessment. Subtype membership, along with membership in the aC and aPR stages, provides important additional information for tailoring smoking prevention materials. Tailored interventions can focus on those adolescents at highest risk and limit or avoid expending resources on those at very low risk.  相似文献   
993.
Dementia with Lewy bodies   总被引:3,自引:0,他引:3  
Dementia with Lewy bodies (DLB) is the second commonest cause of neurodegenerative dementia in older people. It is part of the range of clinical presentations that share a neuritic pathology based on abnormal aggregation of the synaptic protein alpha-synuclein. DLB has many of the clinical and pathological characteristics of the dementia that occurs during the course of Parkinson's disease. Here we review the current state of scientific knowledge on DLB. Accurate identification of patients is important because they have specific symptoms, impairments, and functional disabilities that differ from those of other common types of dementia. Severe neuroleptic sensitivity reactions are associated with significantly increased morbidity and mortality. Treatment with cholinesterase inhibitors is well tolerated by most patients and substantially improves cognitive and neuropsychiatric symptoms. Clear guidance on the management of DLB is urgently needed. Virtually unrecognised 20 years ago, DLB could within this decade be one of the most treatable neurodegenerative disorders of late life.  相似文献   
994.
BACKGROUND: There is a need for an easily administered instrument which can be applied to all patients with restless legs syndrome (RLS) to measure disease severity for clinical assessment, research, or therapeutic trials. The pathophysiology of RLS is not clear and no objective measure so far devised can apply to all patients or accurately reflect severity. Moreover, RLS is primarily a subjective disorder. Therefore, a subjective scale is at present the optimal instrument to meet this need. METHODS: Twenty centers from six countries participated in an initial reliability and validation study of a rating scale for the severity of RLS designed by the International RLS study group (IRLSSG). A ten-question scale was developed on the basis of repeated expert evaluation of potential items. This scale, the IRLSSG rating scale (IRLS), was administered to 196 RLS patients, most on some medication, and 209 control subjects. RESULTS: The IRLS was found to have high levels of internal consistency, inter-examiner reliability, test-retest reliability over a 2-4 week period, and convergent validity. It also demonstrated criterion validity when tested against the current criterion of a clinical global impression and readily discriminated patient from control groups. The scale was dominated by a single severity factor that explained at least 59% of the pooled item variance. CONCLUSIONS: This scale meets performance criteria for a brief, patient completed instrument that can be used to assess RLS severity for purposes of clinical assessment, research, or therapeutic trials. It supports a finding that RLS is a relatively uniform disorder in which the severity of the basic symptoms is strongly related to their impact on the patient's life. In future studies, the IRLS should be tested against objective measures of RLS severity and its sensitivity should be studied as RLS severity is systematically manipulated by therapeutic interventions.  相似文献   
995.
BACKGROUND: Restless legs syndrome is a common yet frequently undiagnosed sensorimotor disorder. In 1995, the International Restless Legs Syndrome Study Group developed standardized criteria for the diagnosis of restless legs syndrome. Since that time, additional scientific scrutiny and clinical experience have led to a better understanding of the condition. Modification of the criteria is now necessary to better reflect that increased body of knowledge, as well as to clarify slight confusion with the wording of the original criteria. SETTING: The restless legs syndrome diagnostic criteria and epidemiology workshop at the National Institutes of Health. PARTICIPANTS: Members of the International Restless Legs Syndrome Study Group and authorities on epidemiology and the design of questionnaires and scales. OBJECTIVE: To modify the current criteria for the diagnosis of restless legs syndrome, to develop new criteria for the diagnosis of restless legs syndrome in the cognitively impaired elderly and in children, to create standardized criteria for the identification of augmentation, and to establish consistent questions for use in epidemiology studies. RESULTS: The essential diagnostic criteria for restless legs syndrome were developed and approved by workshop participants and the executive committee of the International Restless Legs Syndrome Study Group. Criteria were also developed and approved for the additional aforementioned groups.  相似文献   
996.
997.
Intraperirhinal cortex infusion of 17‐β estradiol (E2) impairs object‐recognition memory. However, it is not currently known whether this hormone modulates synaptic plasticity in this structure. Most excitatory synapses in the central nervous system are located on dendritic spines, and elevated E2 levels influence the density of these spines in several brain areas. The goal of the present study was to determine whether differences in dendritic spine density in the perirhinal cortex are observed following high E2 replacement in ovariectomized rats. The density of total spines, and mushroom‐shaped (i.e. mature) spines were compared between a high E2 replacement (10 µg/kg/day, s.c.) and a no replacement condition. The perirhinal cortex is subdivided into Broadmann's area 35 and 36 and so group comparisons were made within each sub‐region separately. High E2 replacement resulted in lower density of mushroom‐shaped spines in area 35 relative to no replacement. There was no effect of high E2 replacement on dendritic spine density in area 36. These findings are consistent with the idea that higher E2 levels reduce dendritic spine density in area 35, which may result from spine shrinkage, or reduced synapse formation. This study provides preliminary evidence for a mechanism through which E2 may impair object‐recognition memory. © 2015 Wiley Periodicals, Inc.  相似文献   
998.
OBJECTIVE: The objective of this study was to define the positive predictive value (PPV) of the Focus herpes simplex virus type 2 (HSV-2) enzyme-linked immunosorbent assay (ELISA) in a low HSV-2 prevalence population and to develop a new test interpretation algorithm. METHODS: HSV-2 Western blots were performed on sera from male sexually transmitted disease clinic patients testing HSV-2 ELISA-positive and used to define a new class of indeterminate HSV-2 ELISA result. HSV-2 Western blots were then prospectively performed on sequential sera with indeterminate HSV-2 ELISAs. RESULTS: Ninety-one (84%) of 108 HSV-2 ELISA-positive sera tested HSV-2 Western blot-positive. Western blot positivity was more common in men without herpes simplex virus type 1 (HSV-1) antibody than in those with HSV-1 antibody (93% vs 76%, P = 0.02) and in men with a history or clinical evidence of genital lesions (88% vs 80%, P = 0.30). Selectively raising the ELISA index value defining HSV-2 positivity from >1.1 to >or=3.0 either among HSV-1-positive men or among those without a history or clinical evidence of genital lesions increased the PPV to >or=93%. Prospective evaluation of an algorithm incorporating HSV-1 serostatus found that 11 of 70 persons with indeterminate HSV-2 ELISAs were Western blot-positive. CONCLUSIONS: Clinicians should consider selectively using a higher index value to define Focus ELISA HSV-2 positivity based on either HSV-1 serostatus or clinical circumstances.  相似文献   
999.
1000.
Although the cycling of eukaryotic cells has long been a primary focus for cancer therapeutics, recent advances in imaging and data analysis allow even further definition of cellular events as they occur in individual cells and cellular subpopulations in response to treatment. High-content imaging (HCI) has been an effective tool to elucidate cellular responses to a variety of agents; however, these data were most frequently observed as averages of the entire captured population, unnecessarily decreasing the resolution of each assay. Here, we dissect the eukaryotic cell cycle into individual cellular subpopulations using HCI in conjunction with unsupervised K-means clustering. We generate distinct phenotypic fingerprints for each major cell cycle and mitotic compartment and use those fingerprints to screen a library of 310 commercially available chemotherapeutic agents. We determine that the cell cycle arrest phenotypes caused by these agents are similar to, although distinct from, those found in untreated cells and that these distinctions frequently suggest the mechanism of action. We then show via subpopulation analysis that these arrest phenotypes are similar in both mouse models and in culture. HCI analysis of cell cycle using data obtained from individual cells under a broad range of research conditions and grouped into cellular subpopulations represents a powerful method to discern both cellular events and treatment effects. In particular, this technique allows for a more accurate means of assessing compound selectivity and leads to more meaningful comparisons between so-called targeted therapeutics.  相似文献   
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