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排序方式: 共有10000条查询结果,搜索用时 401 毫秒
991.
Carmen Cristea Janvin Jan Petter Larsen David P Salmon Douglas Galasko Kenneth Hugdahl Dag Aarsland 《Movement disorders》2006,21(3):337-342
We describe the pattern of cognitive profiles within a community-based sample of patients with Parkinson's disease (PD) and dementia (PDD) using cluster analyses, and compare the results with data from patients with Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). Fifty patients with PDD and 39 with AD from Stavanger, Norway, and 62 patients with DLB from San Diego, CA, USA were diagnosed by either standardized clinical procedures or criteria (all PDD and all AD cases) or necropsy (all DLB cases). Four subgroups were identified: two subgroups with a subcortical cognitive profile (one with mild and one with moderate dementia severity), one subgroup with global impairment and severe dementia, and one subgroup with a cortical cognitive profile and moderate dementia. Of the patients with PDD and with DLB, 56% and 55%, respectively, had a subcortical cognitive profile, compared with only 33% of the AD patients. Conversely, 30% of the patients with PDD and 26% of those with DLB had a cortical cognitive profile, compared with 67% of the patients with AD. These findings suggest that in some patients with PDD, frontosubcortical changes are the main contributing factor to dementia, whereas in other patients, cortical and hippocampal changes are more important. 相似文献
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The goal of the initial treatment for ST-segment elevation myocardial infarction is rapid and effective reperfusion. Randomized trials have demonstrated that primary angioplasty is preferred over thrombolysis if done in a timely manner and by an experienced team. However, due to many factors, performance of primary angioplasty within the goal of 90 min is often not possible. A combined strategy of immediate thrombolysis in the emergency room or in the ambulance followed by angioplasty theoretically could provide early reperfusion with subsequent angioplasty to insure complete reperfusion. Over 17 clinical trials have been reported. Compared with thrombolysis, facilitated angioplasty in the most recent trials has been shown to have a more favorable long-term outcome. Trials comparing facilitated angioplasty with full- or half-dose thrombolysis versus primary angioplasty have been far less favorable with the largest trial to date, the ASSENT (Assessment of the Safety and Efficacy of a New Treatment Strategy with Percutaneous Coronary Intervention)-4 trial, demonstrating a worse outcome in the primary end point of death, congestive heart failure, or shock at 90 days. Pending the results of the FINESSE (Facilitated Intervention with Enhanced Reperfusion Speed to Stop Events) trial, current data suggest that facilitated angioplasty does not offer any advantage over primary angioplasty and may be harmful. 相似文献
995.
BACKGROUND: Spatially discordant cellular alternans form a substrate for development of unidirectional block and ventricular fibrillation. However, the mechanisms responsible for discordant alternans remain poorly understood. Previous work suggests electrical restitution is critical to the development of alternans in single cells. OBJECTIVES: The purpose of this study was to investigate the hypothesis that spatial and temporal heterogeneities of restitution underlie the mechanism eliciting discordant alternans. METHODS: Steady-state pacing was used to elicit concordant cellular alternans in nine Langendorff-perfused guinea pig hearts. A single extrastimulus (S2) was applied every 51st beat following either the even or the odd beat of alternans. The cellular response to S2 was determined using optical mapping to generate action potential duration (APD) restitution curves from 256 ventricular sites for both the even and the odd beats. RESULTS: Restitution kinetics were temporally heterogeneous during alternans, as restitution curves between the even and the odd beats differed significantly. Temporal heterogeneity was quantified by the average separation of restitution between the two curves, or Delta-restitution. Delta-Restitution was spatially heterogeneous and proportional to the amount of alternans at a given ventricular site. A computer simulation based on the experimental results showed the mechanism of discordant alternans was dependent on both spatial and temporal heterogeneities of restitution. CONCLUSION: Both temporal and spatial heterogeneities of restitution exist during cellular alternans in the intact heart. Temporal heterogeneities of restitution, quantified by Delta-restitution, are proportional to the magnitude of cellular alternans. The combination of spatial and temporal heterogeneities of restitution may underlie the genesis of discordant alternans. 相似文献
996.
G Menvielle D Luce P Goldberg I Bugel A Leclerc 《European journal of cancer prevention》2004,13(3):165-172
The aim of this work was to study the effects of alcohol and tobacco consumption on laryngeal and hypopharyngeal cancer and to compare these across subsites (glottis, supraglottis, epilarynx, hypopharynx). Data from a hospital-based case-control study including 504 male cases (105 glottic cancers, 80 supraglottic cancers, 97 epilaryngeal cancers and 201 hypopharyngeal cancers) and 242 male controls with non-respiratory cancers were used for this analysis. Information about sociodemographic characteristics, detailed alcohol and tobacco consumption was collected through face-to-face interviews. Statistical analysis used logistic regression, and subsites were compared with polytomous logistic regressions. The risk of laryngeal and hypopharyngeal cancer increased with tobacco (duration and amount) and alcohol consumption; the effect of both agents was multiplicative. From the lowest to the highest consumption level, odds ratios ranged from 1.4 to 5.9 among regular drinkers and from 3 to 44 among current smokers. Risks among ex-smokers were approximately one-third of those for current smokers. Slightly elevated odds ratios were associated with consumption of black tobacco (OR=1.2) and hand-rolled cigarettes (OR=1.2). The risk of cancer was not clearly associated with the type of alcoholic beverage. Subsites did not differ significantly according to tobacco smoking, but differed according to alcohol consumption, with a significantly higher increased risk for hypopharyngeal than for glottic and supraglottic cancers. 相似文献
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999.
Peter C Belafsky Katy Allen Lynn Castro-Del Rosario David Roseman 《Otolaryngology--head and neck surgery》2004,131(1):26-28
OBJECTIVES: The introduction of 48-hour wireless pH testing offers clinicians a new alternative for the objective documentation of reflux. The success of transnasal wireless pH capsule placement has not been previously described. The purpose of this investigation was to describe our experience with transnasal wireless pH capsule placement. METHODOLOGY: All patients undergoing unsedated transnasal esophagoscopy and wireless pH capsule placement between January 1, 2003 and July 31, 2003 were prospectively evaluated. Data concerning patient tolerance, success of capsule placement and function, complications, and pH recordings were collected. RESULTS: During this time, 46 persons were evaluated. The mean age of the cohort was 52 years. Of the patients, 50% were male. The indications for the procedure were chronic cough (18/46), gastroesophageal reflux disease (18/46), and larygopharyngeal reflux (10). Of the procedures performed, 85% (39/46) were successful. Complications included epistaxis (2/46), laryngospasm (2/46), and vasovagal reaction (1/46). CONCLUSIONS: The transnasal placement of a wireless pH capsule is a safe and effective diagnostic adjunct to unsedated transnasal esophagoscopy. 相似文献
1000.