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Cerebral blood flow relationships associated with a difficult tone recognition task in trained normal volunteers 总被引:2,自引:2,他引:0
Holcomb HH; Medoff DR; Caudill PJ; Zhao Z; Lahti AC; Dannals RF; Tamminga CA 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(6):534-542
Tone recognition is partially subserved by neural activity in the right
frontal and primary auditory cortices. First we determined the brain areas
associated with tone perception and recognition. This study then examined
how regional cerebral blood flow (rCBF) in these and other brain regions
correlates with the behavioral characteristics of a difficult tone
recognition task. rCBF changes were assessed using H2(15)O positron
emission tomography. Subtraction procedures were used to localize
significant change regions and correlational analyses were applied to
determine how response times (RT) predicted rCBF patterns. Twelve trained
normal volunteers were studied in three conditions: REST, sensory motor
control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral
activation of primary auditory cortices, cerebellum and bilateral inferior
frontal gyri. DEC-SMC produced significant clusters in the right middle and
inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus
and supplementary motor area; the left insula/claustrum; and the left
cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a
positive correlation in right inferior and middle frontal cortex; rCBF in
bilateral auditory cortices and cerebellum exhibited significant negative
correlations with RT These changes suggest that neural activity in the
right frontal, superior temporal and cerebellar regions shifts back and
forth in magnitude depending on whether tone recognition RT is relatively
fast or slow, during a difficult, accurate assessment.
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数据来源:检索MEDLINE数据库从1970年1月至2003年10月出版的所有文献.并手工检索参考文献中的相关文献。纳入标准:以人为对象的临床试验或观察性研究,且以英语发表的文献。数据提取和合成:由3位作者分别提取数据,意见不同则由讨论解决。记录一系列指标:菌斑指数(PI)、牙石指数、牙龈指数(GI)、探诊出血指数(BOP)、牙周探诊深度(PPD)、临床附着丧失(CAL)、牙龈退缩、牙周指数和骨丧失指数。用血液中糖化血红蛋白百分浓度显示糖尿病控制与否。评估各牙周参数的整体差异,并应用固定效应模型或随机效应模型计算相应的95%CI。用Q检验进行同质性检验。用漏斗图检测发表偏倚。结果:18个横断面对照研究、3个前瞻性队列研究和2个临床试验的基线资料入选。 相似文献
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Prevention in practice: results of a 2-year follow-up of routine health promotion interventions in general practice 总被引:2,自引:0,他引:2
BACKGROUND.: The effectiveness of health promotion activity in general practiceon risk factor reduction for coronary heart disease remainsthe subject of active debate. OBJECTIVE.: The study aimed to assess the impact of practice-based healthcheck-ups on health behaviours over a 2-year period. METHOD.: A general practice cohort of 7123 patients from 18 practiceswas surveyed. Eight hundred and forty (12%) patients had beenoffered a heafth check within a 12-month period from September1992 and 621 (9%) received one. Two hundred and fifty patients(40%) were asked back for follow-up after their health check. RESULTS.: Over a 2-year period there was no difference in smoking cessation,alcohol consumption, weight loss nor the amount of exercisetaken between those who attended for a health check and thosewho did not. The food score chosen to assess dietary change(Oxcheck) showed a statistically significant 1.16-point risefor the whole sample over the survey period. There was a significantdifference in mean food score change between heafth check attendersand non-attenders (Mann-Whitney U test: P << 0.002). Maintenanceof dietary improvement over a 2-year period was not affectedby health check attendance. CONCLUSIONS.: This study confirms the low impact of health checks on the selfreported modification of cardiovascular risk factors and showsthat maintenance of appropriate health behaviour change is nomore likely in those who have received a health check. Keywords. Health promotion, general practice. 相似文献