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排序方式: 共有425条查询结果,搜索用时 31 毫秒
1.
Smoking and raven IQ 总被引:1,自引:0,他引:1
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks. 相似文献
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性病艾滋病恐惧症110例心理咨询情况 总被引:2,自引:0,他引:2
目的:了解性病艾滋病恐惧症形成原因,寻找预防控制的措施.方法:对110例性病艾滋病恐惧症患者的临床症状和全身不适进行分析.结果:绝大多数患者都有不洁性交史,占82%,发病与患者的文化程度、心理因素和医学误导有关.结论:目前应加强对性病艾滋病恐惧症的预防、加强对性病艾滋病知识的宣传教育和心理疏导. 相似文献
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ObjectivesTo determine if upper-body strength or power changes during the competitive season for elite Australian rules footballers and what influence the number of training years has on any changes.DesignRepeated measures.MethodsTwenty elite Australian rules footballers were assessed at preseason, in-season and postseason. Strength was assessed by the 1 Repetition Maximum bench press and power was assessed by bench press throws. Athletes’ results were analysed as a whole group as well as being divided into two groups according to training years: less than 3 years training and greater than 3 years training. All athletes performed the same resistance training program.ResultsThere were no significant differences in height, body mass, or skinfold measurements between the two age groups. As a whole group, there was no significant change in 1RM bench press. There was a small but significant decrease in mean bench throw power in-season (525 W) compared to preseason (542 W) and it then increased at postseason (541 W). Within group analysis revealed the in-season decrease in upper-body power was largely pertaining to the younger athletes. The older group maintained their upper body power levels while the younger group decreased power in-season (4%) before regaining it at season's end.ConclusionOlder footballers were able to maintain their upper body power while the younger footballers had a small but significant decrease in-season before regaining it by season's end. The overall volume of training and playing appears to have affected the younger athletes’ power more than older athletes. Both age groups maintained upper body strength. 相似文献
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John Yiannikas Jianis Marcomichelakis Peter Taggart Brian H. Kelly Richard Emanuel 《The American journal of cardiology》1981,47(2):238-243
Fifty asymptomatic men, 44 (88 percent) of whom were pilots or allied aviation personnel, were referred because of resting ST-T electrocardiographic changes indistinguishable from those of myocardial ischemia. Because of the nature of their occupations, cardiac catheterization was performed to establish the presence or absence of coronary artery disease. Exercise tests were performed and analyzed retrospectively with respect to exercise-induced changes in the S-T segment and R wave amplitude. The results were correlated with coronary angiographic and echocardiographic findings.The 50 subjects were classified into two groups: Group I, 5 men with angiographically proved coronary artery disease, and Group II, 45 men without significant coronary arterial obstruction. Analysis of the S-T segment changes at peak exercise showed 21 subjects (42 percent) with a positive exercise test and 29 (58 percent) with a negative test. All subjects in Group I had a positive test. Sixteen subjects (35 percent) in Group II had a false positive result. Analysis of exercise-induced changes in R wave amplitude revealed that six subjects had a positive R wave response on the basis of sum of the changes in voltage in the leads measured (Δ∑R). Four of the six subjects had coronary artery disease and the other two were thought to have a cardiomyopathy. One subject with coronary artery disease had a negative R wave response. Echocardiography revealed five subjects with asymmetric septal hypertrophy; two of these had a positive exercise test and three a negative test on the basis of S-T segment criteria.Thus, symptom-limited treadmill exercise testing of asymptomatic men with resting ST-T electrocardiographic changes produced a high incidence rate of false positive results when S-T segment criteria were used, whereas analysis of changes in R wave amplitude yielded only two false positive results, both in men who had evidence of other heart disease. 相似文献
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Robert M. Walter Ernest M. Gold Con A. Michas John W. Ensinck 《Metabolism: clinical and experimental》1980,29(11):1037-1040
Five morbidly obese subjects with fasting normoglycemia underwent catheterization of portal and peripheral veins immediately prior to jejunoileal bypass surgery. Levels of immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and glucose were determined in simultaneously obtained serum samples before and after infusion of arginine. Portal levels exceeded peripheral levels by at least 50% with IRI and by 30%–40% with IRG. These results were similar to those reported in nonobese subjects and show that in morbid obesity as well as in nonobese states, peripheral insulin to glucagon molar ratios () underestimate portal . Although hepatic extraction was not specifically measured, the data suggest that the peripheral levels of insulin and glucagon reported in morbid obesity result from alterations in secretion and not altered extraction. 相似文献
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Jenny Bj?rkqvist Steven de Maat Urs Lewandrowski Antonio Di Gennaro Chris Oschatz Kai Sch?nig Markus M. N?then Christian Drouet Hal Braley Marc W. Nolte Albert Sickmann Con Panousis Coen Maas Thomas Renné 《The Journal of clinical investigation》2015,125(8):3132-3146
Hereditary angioedema type III (HAEIII) is a rare inherited swelling disorder that is associated with point mutations in the gene encoding the plasma protease factor XII (FXII). Here, we demonstrate that HAEIII-associated mutant FXII, derived either from HAEIII patients or recombinantly produced, is defective in mucin-type Thr309-linked glycosylation. Loss of glycosylation led to increased contact-mediated autoactivation of zymogen FXII, resulting in excessive activation of the bradykinin-forming kallikrein-kinin pathway. In contrast, both FXII-driven coagulation and the ability of C1-esterase inhibitor to bind and inhibit activated FXII were not affected by the mutation. Intravital laser-scanning microscopy revealed that, compared with control animals, both F12–/– mice reconstituted with recombinant mutant forms of FXII and humanized HAEIII mouse models with inducible liver-specific expression of Thr309Lys-mutated FXII exhibited increased contact-driven microvascular leakage. An FXII-neutralizing antibody abolished bradykinin generation in HAEIII patient plasma and blunted edema in HAEIII mice. Together, the results of this study characterize the mechanism of HAEIII and establish FXII inhibition as a potential therapeutic strategy to interfere with excessive vascular leakage in HAEIII and potentially alleviate edema due to other causes. 相似文献