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81.
Psychotic major depression (PMD) is hypothesized to be a distinct clinical entity from nonpsychotic major depression (NPMD). However, neurobiological evidence supporting this notion is scarce. The aim of this study is to identify gray matter volume (GMV) differences between PMD and NPMD and their longitudinal change following electroconvulsive therapy (ECT). Structural magnetic resonance imaging (MRI) data from 8 independent sites in the Global ECT-MRI Research Collaboration (GEMRIC) database (n = 108; 56 PMD and 52 NPMD; mean age 71.7 in PMD and 70.2 in NPMD) were analyzed. All participants underwent MRI before and after ECT. First, cross-sectional whole-brain voxel-wise GMV comparisons between PMD and NPMD were conducted at both time points. Second, in a flexible factorial model, a main effect of time and a group-by-time interaction were examined to identify longitudinal effects of ECT on GMV and longitudinal differential effects of ECT between PMD and NPMD, respectively. Compared with NPMD, PMD showed lower GMV in the prefrontal, temporal and parietal cortex before ECT; PMD showed lower GMV in the medial prefrontal cortex (MPFC) after ECT. Although there was a significant main effect of time on GMV in several brain regions in both PMD and NPMD, there was no significant group-by-time interaction. Lower GMV in the MPFC was consistently identified in PMD, suggesting this may be a trait-like neural substrate of PMD. Longitudinal effect of ECT on GMV may not explain superior ECT response in PMD, and further investigation is needed.  相似文献   
82.
背景 在美国,脑血管病是导致死亡的第3位原因.在所有卒中病例中,由既往无症状颈动脉狭窄(carotid artery stenosis,CAS)造成的比例并不高.1996年,美国预防服务特别工作组得出结论,没有充分的证据推荐或反对通过体格检查或颈动脉超声在无症状患者中对CAS进行筛查.目的 评估采用双功能超声对无症状患者进行筛查以及应用颈动脉内膜切除术(carotid endarterectomy,CEA)对CAS进行治疗的利弊.数据来源 Medline和Cochrane数据库(检索日期为1994年1月-2007年4月)、最近的系统评价、检索文章的参考文献以及专家的建议.研究选择 选择对CAS进行筛查的英文随机对照试验(randomized controlled trial,RCT)、对CEA与药物治疗进行比较的RCT、筛查试验的系统评价以及对CEA害处的观察性研究,以回答下列问题:是否有直接证据表明使用超声筛查无症状CAS能降低卒中风险? 超声检测CAS的准确性如何? CEA治疗能否降低卒中残疾率或病死率? CAS筛查或CEA治疗是否会给患者带来伤害? 数据提取 使用预先确定的特殊工作组标准,对所有研究进行评估、提炼和质量评定.数据综合 至今尚未进行过CAS筛查的RCT.根据系统评价,超声检测CAS的敏感性约为94%,特异性约为92%.在经过选择的患者中由选定的外科医生进行手术治疗可使5年卒中风险降低约5%.在RCT中,CEA的30 d卒中和死亡发生率为2.7%~4.7%,而在观察性研究中的发生率更高(高达6.7%).局限性 证据不足以对有临床意义的CAS进行风险分层.对患者行CEA与药物治疗相比较的RCT是在经过选择的人群中由特定的外科医生实施的.结论 对无症状患者进行CAS筛查以及进行CEA治疗造成的实际卒中风险降低率尚不清楚;由于整个无症状人群中可治疗疾病的总体患病率不高且治疗会造成一定的害处,因此筛查的益处受到限制.  相似文献   
83.
84.
OBJECTIVE: In several large, well-designed, randomized, double-blind studies, the opiate antagonist naltrexone demonstrated efficacy in the treatment of alcohol dependence. Specifically, when combined with certain psychosocial therapies, naltrexone reduces the number of drinking days, heavy drinking, and time to relapse to alcohol use in alcohol-dependent individuals. Whether this efficacy can be generalized to individuals who have alcohol use disorders and present for treatment at front-line community treatment programs has not been well established. METHODS: A total of 145 patients who presented for treatment at a rural community substance abuse treatment center were randomized to receive naltrexone 50 mg daily plus usual program treatment (n = 54), placebo plus usual treatment (n = 43), or usual treatment alone (n = 48) for 12 week. A total of 133 participants had at least one follow-up visit. Primary outcome measures included percent days drinking, average drinks per drinking day, average drinks per day, heavy drinking days (four or more for women and six or more for men), and time to first heavy drinking day. Secondary measures included changes in serum biological markers (alkaline phosphatase, alanine transaminase, aspartate transaminase, and gamma-glutamyltransferase), craving, and psychosocial functioning. RESULTS: In the intention-to-treat analysis, there were no between-group differences for any of the primary drinking outcomes at 12 weeks. In post hoc exploratory analyses, the entire sample of participants was divided into two new groups: (1) people who drank during the 2 weeks before the start of medication (entry drinkers) and (2) people who did not drink during this interval (entry abstainers). Entry abstainers were at an advantage at study entry in that they were significantly more likely to have an inpatient hospitalization immediately before entry into outpatient treatment. Mixed-model analysis of variance revealed a main effect for entry group at the 12-week treatment endpoint on the primary outcome measures of percent days drinking, average drinks per drinking day, average drinks per day, heavy drinking days, and time to first heavy drinking day. Participants in any of the randomized groups who were entry abstainers had significantly better improvement on all of the primary outcome measures. The abstainer groups that were randomized to placebo and usual treatment had significantly better outcomes than the entry drinkers in those perspective groups. However, for the naltrexone-treated group, entry drinkers and entry abstainers had similar improvement in drinking-related outcomes. CONCLUSIONS: These data suggest that naltrexone may offer particular benefit to patients who continue to drink during the early stages of the trial as compared with those who have achieved abstinence before treatment entry.  相似文献   
85.
Background: The nitric oxide synthasase‐1 gene (NOS1) has been implicated in mental disorders including schizophrenia and variation in cognition. The NOS1 variant rs6490121 identified in a genome wide association study of schizophrenia has recently been associated with variation in general intelligence and working memory in both patients and healthy participants. Whether this variant is also associated with variation in early sensory processing remains unclear. Methods: We investigated differences in the P1 visual evoked potential in a high density EEG study of 54 healthy participants. Given both NOS1's association with cognition and recent evidence that cognitive performance and P1 response are correlated, we investigated whether NOS1's effect on P1 response was independent of its effects on cognition using CANTAB's spatial working memory (SWM) task. Results: We found that carriers of the previously identified risk “G” allele showed significantly lower P1 responses than non‐carriers. We also found that while P1 response and SWM performance were correlated, NOS1 continued to explain a significant proportion of variation in P1 response even when its effects on cognition were accounted for. Conclusion: The schizophrenia implicated NOS1 variants rs6490121 influences visual sensory processing as measured by the P1 response, either as part of the gene's pleiotropic effects on multiple aspects of brain function, or because of a primary influence on sensory processing that mediates the effects already seen in higher cognitive processes. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
86.
Attributional style is defined as the pervasive tendency to explain the cause of social actions in terms of oneself, or others, or the context of the event. While the clinical correlates of this aspect of social cognition have been widely researched, its links with relationship style and neuropsychological performance, although hypothesised, have received less attention. This study investigated whether attributional style is predicted by variance in either relationship style or neuropsychological performance in schizophrenia. We assessed attributional style (using the Internal, Personal and Situational Attributions Questionnaire [IPSAQ]), relationship style (using Bartholomew and Horowitz's Relationship Questionnaire), and neuropsychological function (using the Wechsler Abbreviated Scale of Intelligence, the Wechsler Memory Test, and the Cambridge Automated Test Battery) in 73 stabilised outpatients with chronic schizophrenia and 78 controls matched for age and gender. 'Externalising bias' (attributing positive rather than negative events to oneself) was predicted by verbal ability in both patients and controls. 'Personalising bias' (attributing negative events to others rather than to situational factors) was predicted by higher secure relationship style ratings, but only in the patient group. This study highlights the importance of relationship style and neuropsychological performance for different aspects of attributional style in schizophrenia.  相似文献   
87.
Evidence based practice is essential to advanced practice nursing, enabling the delivery of quality care and improved patient outcomes. As the name suggests, it requires healthcare decisions to be based on the best available and current evidence. Advanced practice nurses need astute critical analysis skills to appraise the evolving literature, and require research skills to lead on scientific inquiry and develop the profession. Yet, advanced practice nurses may not recognize themselves as research leaders. Participation in a journal club can promote evidence-based practice, improve clinician's critical thinking skills, and expose members to different research methodologies, however, nurses continue to face barriers to participation in these clubs. Establishing a clinical-academic partnership appears to be both mutually beneficial for clinicians and academics and is a significant enabler in the sustainability and functioning of the club through sharing expertise and experience. A supportive workplace culture is favourable to research utilization and knowledge translation. This paper outlines the role, practicalities, challenges, and benefits of setting up a hybrid urology journal and research club for advanced practice nurses in a clinical-academic partnership.  相似文献   
88.
89.
BRCA1 and BRCA2 screening in women at high‐risk of breast cancer results in the identification of both unambiguously defined deleterious mutations and sequence variants of unknown clinical significance (VUS). We examined a population‐based sample of young women with contralateral breast cancer (CBC, n=705) or unilateral breast cancer (UBC, n=1398). We identified 470 unique sequence variants, of which 113 were deleterious mutations. The remaining 357 VUS comprised 185 unique missense changes, 60% were observed only once, while 3% occurred with a frequency of >10%. Deleterious mutations occurred three times more often in women with CBC (15.3%) than in women with UBC (5.2%), whereas combined, VUS were observed in similar frequencies in women with CBC and UBC. A protein alignment algorithm defined 16 rare VUS, occurring at highly conserved residues and/or conferring a considerable biochemical difference, the majority located in the BRCA2 DNA‐binding domain. We confirm a multiplicity of BRCA1 and BRCA2 VUS that occur at a wide range of allele frequencies. Although some VUS inflict chemical differences at conserved residues, suggesting a deleterious effect, the majority are not associated with an increased risk of CBC. © 2010 Wiley‐Liss, Inc.  相似文献   
90.
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