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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
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Christopher D Gardner James L Zehnder Alison J Rigby Joel R Nicholus John W Farquhar 《Blood coagulation & fibrinolysis》2007,18(8):787-793
Several case reports have implicated Ginkgo biloba in clinically adverse bleeding disorders. Ginkgo biloba has been reported to increase pain-free walking distance among patients with peripheral artery disease (PAD). Standard PAD therapy includes 325 mg/day aspirin. The objective of this study was to examine potential adverse effects of concomitant aspirin and Ginkgo biloba on platelet function. Ginkgo biloba (EGb 761, 300 mg/day) was compared with placebo for effects on measures of platelet aggregation among adults consuming 325 mg/day aspirin in a randomized, double-blind, placebo-controlled, parallel design trial of 4-week duration. Participants were adults, age 69 +/- 10 years, with PAD or risk factors for cardiovascular disease. Outcome measures included platelet function analysis (PFA-100 analyzer) using ADP as an agonist (n = 26 placebo; n = 29 ginkgo), and platelet aggregation using ADP, epinephrine, collagen and ristocetin as agonists (n = 21 placebo; n = 23 ginkgo). Participants kept daily logs of bleeding or bruising episodes. There were no clinically or statistically significant differences between treatment groups for any agonists, for either PFA-100 analysis or platelet aggregation. Reports of bleeding or bruising were infrequent and similar for both study groups. In conclusion, in older adults with PAD or cardiovascular disease risk, a relatively high dose of Ginkgo biloba combined with 325 mg/day daily aspirin did not have a clinically or statistically detectable impact on indices of coagulation examined over 4 weeks, compared with the effect of aspirin alone. No adverse bleeding events were observed, although the trial was limited to a small sample size. 相似文献
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One of the important steps on the road to becoming expert in a motor skill occurs when the individual can perform the movements in a seemingly effortless and automatic fashion. The authors review two lines of investigations, namely, fMRI and mathematically guided studies of the dynamics of skill acquisition, that suggest that this road to automatic involves two steps: (1) an increasing reliance on the self-regulatory aspects of the motor task, and (2) a minimization of the role of mechanisms based on intentionally directed corrective movements. The interplay between these two mechanisms implies that, at a given skill level, performance decreases whenever intention intervenes. The observation that psychological factors may be as important as mechanical repetition for the development of expertise has important implications for the design of neurorehabilitative strategies. 相似文献
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Aisling Mary McMahon Fardod O'Kelly Kheng Tian Lim Narayanasamy Ravi John Vincent Reynolds 《Patient safety in surgery》2009,3(1):19
Esophageal perforation is associated with a significant risk of morbidity and mortality. We report herein a case of lye-induced
esophageal perforation managed successfully by employing endoscopic T-tube placement with a successful outcome. 相似文献
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Scalp electrical recording during paralysis: quantitative evidence that EEG frequencies above 20 Hz are contaminated by EMG. 总被引:2,自引:0,他引:2
Emma M Whitham Kenneth J Pope Sean P Fitzgibbon Trent Lewis C Richard Clark Stephen Loveless Marita Broberg Angus Wallace Dylan DeLosAngeles Peter Lillie Andrew Hardy Rik Fronsko Alyson Pulbrook John O Willoughby 《Clinical neurophysiology》2007,118(8):1877-1888
OBJECTIVE: To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. METHODS: Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. RESULTS: EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. CONCLUSIONS: Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. SIGNIFICANCE: This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation. 相似文献
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John A. Tomenson Graham A. Matthews 《International archives of occupational and environmental health》2009,82(8):935-949
Purpose The present investigation looks in detail at the causes and types of health incidents reported by 6,300 mainly smallholder
agrochemical users in 24 countries during 2005 and 2006.
Methods The investigation is based on a questionnaire survey of knowledge, attitude and practice that concentrated on the sequence
of events from purchasing the pesticide to disposal. Information was also collected about health problems experienced while
using agrochemicals. The survey targeted mainly smallholder knapsack spray operators who were expected to be at a highest
risk of exposure.
Results In the 12 months prior to interview, 1.2% of users reported an agrochemical-related incident that required hospital treatment,
5.8% reported an incident requiring at least trained medical treatment but not hospitalisation and 19.8% reported only a minor
sign or symptom. Users who had experienced an incident involving agricultural equipment were 3.38 (95% CI 2.29–4.99) times
more likely to experience an agrochemical-related health incident, but confident users who felt that their use of personal
protective equipment while spraying was best practice were 0.60 (95% CI 0.44–0.84) times less likely to experience such an
incident. Over 80% of product-related incidents were caused by insecticides and the incidence rate per spraying time for incidents
linked to insecticides was significantly higher than that for fungicides or herbicides. Headache/dizziness and nausea/vomiting,
often smell related, were the most common symptoms reported by users who listed agrochemical products that had caused them
health problems (52 and 38% of product mentions, respectively).
Conclusions In most countries, the incidence of serious health effects was low; however, there was a high incidence of minor signs and
symptoms in a few countries, especially in Africa. A disproportionate number of incidents occurred during insecticide use
relative to the time that they were sprayed. Failure to exercise caution as indicated by whether users had incidents involving
agricultural equipment or livestock, and lack of confidence in their practices were the most important predictors of agrochemical-related
incidents. 相似文献
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