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排序方式: 共有666条查询结果,搜索用时 15 毫秒
1.
BACKGROUND: Studies have shown that alcoholics have smaller brain volumes than non-alcoholic cohorts, but an effect of family history (FH) of heavy drinking on brain volume has not been demonstrated. We examined the relationship between an FH of heavy drinking and both brain shrinkage as measured by the ratio of brain volumes to intracranial volume (ICV) as well as maximal brain growth as measured by ICV in early-onset and late-onset alcoholics. METHODS: With T1-weighted resonance imaging, we measured ICV, brain volume, and white and gray matter volume in adult treatment-seeking late-onset and early-onset alcoholics with either a positive or a negative FH of heavy alcohol use, and in healthy control subjects. We also calculated brain shrinkage using a ratio of soft tissue volumes to ICV. RESULTS: The FH positive alcoholic patients had significantly smaller ICVs than FH negative patients, suggesting smaller premorbid brain growth. Brain shrinkage did not correlate with FH. Late-onset alcoholics showed a greater difference in ICV between FH positive and FH negative patients than early-onset alcoholics. Late-onset FH positive patients also had significantly lower IQ scores than late-onset FH negative patients, and IQ scores were correlated with ICV. CONCLUSIONS: These data provide evidence that parental alcohol use might increase risk for alcoholism in offspring in part by a genetic and/or environmental effect that might be related to reduced brain growth. 相似文献
2.
目的比较IQ200全自动尿液分析仪与人工镜检法检测尿中红细胞的结果。方法用IQ200全自动尿液分析仪与人工镜检法对100份尿标本平行测定并观察草酸钙和霉菌孢子对尿中红细胞检测结果的影响。结果草酸钙和霉菌孢子可影响IQ200全自动尿液分析仪对尿中红细胞的测定结果。结论对IQ200全自动尿液分析仪检测出的高红细胞值,建议用人工镜检法确认,避免出现检测误差。 相似文献
3.
Sleep apnea-related cognitive deficits and intelligence: an implication of cognitive reserve theory 总被引:3,自引:0,他引:3
Alchanatis M Zias N Deligiorgis N Amfilochiou A Dionellis G Orphanidou D 《Journal of sleep research》2005,14(1):69-75
Cognitive deficits in patients with obstructive sleep apnea syndrome (OSAS) are well demonstrated, but the pathophysiology of these deficits is still controversial, as the relationship between OSA severity and cognitive deficits is usually weak. Our study considers the possible relationship between OSA-related cognitive deficits and the overall intellectual function of OSA patients. Forty-seven OSA patients and 36 normal individuals underwent a neuropsychological battery test assessing attention and alertness. According to the resulting IQ score, patients and controls were divided into a high-intelligence group (IQ > or = 90th percentile) and a normal-intelligence group (50 < or = IQ < 90%ile). Between the two patient groups there were no significant differences noticed, regarding OSA severity or sleepiness. High-intelligence patients showed the same attention/alertness performance compared with the high-intelligence controls. On the contrary, patients with normal-intelligence showed attention/alertness decline compared with the normal-intelligence control group. The two patient groups were re-examined with the same battery test after at least 1 year of CPAP treatment. At re-examination neither patient group showed any differences regarding attention and alertness compared with the control groups. We assume that high-intelligence may have a protective effect against OSA-related cognitive decline, perhaps due to increased cognitive reserve. 相似文献
4.
Twin studies provide estimates of genetic and environmental contributions to cognitive ability differences, but could be based
on biased samples. Here we report whole-population estimates using twins from unique mental surveys in Scotland. The Scottish
Mental Surveys of 1st June 1932 (SMS1932) and 4th June 1947 (SMS1947), respectively, administered the same validated verbal
reasoning test to almost everyone born in 1921 or 1936 and attending school in Scotland. There were 572 twin pairs from the
SMS1932, and 517 pairs from the SMS1947. Information on zygosity was unavailable. A novel application of a mixture distribution
was used to estimate genetic and environmental components of verbal reasoning variation by maximum likelihood. We found consistent
heritability (~0.70) and shared environment (~0.21) estimates. The estimates did not change substantially when additional
quantitative traits (height and weight) were added in a multivariate analysis. More generally for studies in genetics, the
methodological innovation developed here implies that large (national) data collections can provide sufficient information
on twin pairs to estimate genetic parameters, even without zygosity. 相似文献
5.
John C. Loehlin 《Behavior genetics》1978,8(5):415-436
Three different published heredity-environment analyses of Jencks's summary correlations for IQ have yielded strikingly different results. It is shown empirically that differences in selection of data and in computational procedures and logical inconsistencies in specifying equations are not responsible for the differences in results. Rather, the differences trace to the underlying assumptions made by the various authors. The analyses suggest that the assumptions concerning genetic dominance, assortative mating, and special twin environments were especially critical, while those regarding selective placement and different modes of environmental transmission were not. 相似文献
6.
A recent controversy has given reason to examine the place of Burt's data among other behavioral genetic data on IQ. Although Burt's kinship correlations are higher than the average of other studies, his results are generally consistent with other data. 相似文献
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9.
We estimate potential risks to human health in the UK from dietary exposure to lead from wild gamebirds killed by shooting. The main source of exposure to lead in Europe is now dietary. We used data on lead concentrations in UK gamebirds, from which gunshot had been removed following cooking to simulate human exposure to lead. We used UK food consumption and lead concentration data to evaluate the number of gamebird meals consumed weekly that would be expected, based upon published studies, to result in changes, over and above those resulting from exposure to lead in the base diet, in intelligence quotient (IQ), Systolic Blood Pressure and chronic kidney disease (CKD) considered in a recent opinion of the European Food Safety Authority (EFSA) to be significant at a population level and also in SAT test scores and in rates of spontaneous abortion. We found the consumption of <1 meal of game a week may be associated with a one point reduction in IQ in children and 1.2–6.5 gamebird meals per week may be associated with the other effects. These results should help to inform the development of appropriate responses to the risks from ingesting lead from ammunition in game in the UK and European Union (EU). 相似文献
10.
《ALTER. European Journal of Disability research, Journal europeen de recherche sur le handicap》2014,8(1):30-39
There is no international consensus concerning the diagnostic criteria used to diagnose a learning disability (LD). In fact, various diagnostic criteria are used and interpreted differently in different countries. A common denominator can only be found in the fact that intelligence quotient (IQ) is often seen as important in order to identify LD, either in the framework of discrepancy models between cognitive ability and achievement or in the context of models relating LD to below-average IQ (Grünke, 2004). The present paper examines the criteria that are used for the diagnosis of LD in Styria, a federal state of Austria. For this purpose, 25 special educational needs (SEN) reports of children identified as having learning disabilities were examined. In addition, three expert interviews with school administration authorities were conducted. The results provide a first indication that IQ scores are not important for the diagnosis of LD in Styria. In fact, the diagnostic procedure seems to be quite unregulated and standardized tests are hardly ever used in this context. Moreover, the results show that a diagnosis of LD in Styria is usually based on poor reading skills, poor basic arithmetic skills, deficits in German language, and/or behavioral problems. 相似文献