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31.
32.
目的探讨儿童行为问题与社交能力之间的的关孔方法使用Achenbach’s儿童行为量表对1051名儿童进行筛查,检出98名行为异常者,计数统计其社交项目与总体儿童社交项目人数比较之,x2统计分析。结果在活动的技巧水平上,在家庭关系中,在校学习对知识的理解、掌握程度、心情舒畅程度等方面,异常儿不如总体(P<0.05),但在活动的时间、对外社交及学习成绩方面二者无明显差异(P>0.05)。结论儿童行为问题与社交能力的关系。并不是单一的正、负相关所能概括的,应该具体问题具体分析,审视其全面。 相似文献
33.
Jeffrey A. Gray Stephen N. Mitchell Michael H. Joseph Grigory A. Grigoryan Sharon Dawe Helen Hodges 《Drug development research》1994,31(1):3-17
Data are reviewed, largely from experiments in the authors'laboratory, that suggest three modes of action of systemic nicotine in producing three different types of effect upon behavior and cognitive function. (1) Preexposure of a stimulus without consequence makes it harder subsequently to form associations to that stimulus, a form of selective attention known as latent inhibition. Latent inhibition is blocked by nicotine, an effect that is apparently mediated by a nicotine-induced increase in dopamine release in the nucleus accumbens. (2) A single dose of nicotine proactively increases the partial reinforcement extinction effect measured several weeks later: that is, resistance to extinction is decreased by nicotine in animals that have been trained on a continuous reinforcement schedule, and increased in animals trained on a partial reinforcement schedule. This effect appears to be due to increased synthesis of tyrosine hydroxylase in the cell bodies of noradrenergic neurons in the locus coeruleus, followed by axonal transport to the hippocampus and increased synthesis and release of noradrenaline in that structure. (3) Nicotine improves vigilance in animals with cognitive deficits due to destruction of the forebrain cholinergic projection system, either as a consequence of excitotoxic lesions of the nuclei of origin of this system or after prolonged alcohol consumption; and also in human subjects with Alzheimer's disease (in which this system undergoes degeneration). This effect is most likely due to an action at denervated cholinergic synapses in the hippocampus and neocortex. © 1994 Wiley-Liss, Inc. 相似文献
34.
This experiment was undertaken to provide a pharmacological characterization of performance on a task involving food-related instrumental and consummatory behavior. Rats were tested in an operant chamber in which there was a choice between pressing a lever to receive a preferred food (Bioserve pellets) or approaching and consuming a less-preferred food (Lab Chow). The lever pressing schedule was a fixed ratio 5 (FR5). Rats usually pressed the lever at high rates to obtain the preferred food, and typically ate little of the lab chow even though it was freely available in the chamber concurrently with the lever pressing schedule. Previous work has shown that injection of dopamine (DA) antagonists, or depletion of DA in the nucleus accumbens, caused a substantial shift in behavior such that lever pressing was reduced but chow consumption increased. In the present study it was shown that the DA antagonist haloperidol decreased lever pressing and increased chow consumption at doses of 0.1 and 0.15 mg/kg. The D1 antagonist SCH 23390 (0.05, 0.1 and 0.15 mg/kg) and the non-selective DA antagonistcis-flupenthixol (0.3 and 0.45 mg/kg) decreased lever pressing and produced substantial increases in chow consumption. The D2 antagonist sulpiride decreased lever pressing, but produced only slight increases in chow intake at the highest dose. Pentobarbital reduced lever pressing and increased chow consumption at 10.0 mg/kg. The muscarinic agonist pilocarpine produced dose-related decreases in lever pressing, but failed to increase chow consumption. Amphetamine produced dose-related decreases in both lever pressing and chow consumption. These results indicate that low/moderate doses of the DA antagonists haloperidol,cis-flupenthixol and SCH 23390 can suppress lever pressing in doses that leave the animal directed towards food acquisition and consumption. 相似文献
35.
Reyna O. Calderon B. Maggio T. J. Neuberger G. H. Devries 《Journal of neuroscience research》1993,34(2):206-218
The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties. © 1993 Wiley-Liss, Inc. 相似文献
36.
Bo Sikström M.D. Dan Hellberg M.D. Ph.D. Staffan Nilsson M.D. Ph.D. Christina Brihmer M.D. Ph.D. Per-Anders Mårdh M.D. Ph.D. 《Archives of sexual behavior》1996,25(4):361-372
In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared
to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number
of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad,
oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI,
i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI
shows most of the epidemiological characteristics of a sexually transmitted disease. 相似文献
37.
彭勃 《齐齐哈尔医学院学报》2004,25(3):250-251
目的 联合应用影像学(胸部X线和CT)提高纤支镜对肺癌的诊断。方法选择我院纤支镜后组织病理学确诊的肺癌177例,全部病例在做纤支镜前1周内进行胸部X线或CT检查,并将影像学征象与纤支镜下表现及其病理学类型进行对照分析。结果中央型肺癌165例,周围型肺癌12例;纤支镜下主要表现有:外向型生长98例,浸润型生长63例,仅见间接征象5例,未见异常12例;组织病理学类型:鳞癌117例,腺癌29例,小细胞癌24例,其它肿瘤7例;影像学征象表现有:肺部肿块影116例,阻塞性肺炎表现为主27例,以局限性肺不张表现为主19例,片状模糊的阴影12例,两肺多发结节影3例。结论 纤支镜和影像学征象对肺癌的诊断各有特点,两者联合应用,可取长补短,提高肺癌的诊断。 相似文献
38.
使用N-甲基吗啉-N-氧化物的水合物(NMMO·H2O)作为再生丝素的溶剂.可以得到w=0.10~0.25的再生丝素/NMMO·H2O溶液.研究了再生丝素/NMMO·H2O溶液流变性能,讨论了剪切速率、温度和溶液中的再生丝素的含量对再生丝素/NMMO·H2O溶液流变性能的影响. 相似文献
39.
文章以云南罗平医院为研究对象,调查了65名一般员工和21名科主任级中层领导,使用PM量表对该医院的高层及中层领导行为进行评估,对情景因素与领导行为的内在联系进行探讨,并提出改进对策。目的是了解员工需求,促进人力资源合理配置,从而提高医院的管理水平。 相似文献
40.
Rapid improvements in the capacity of data processing due to technological breakthroughs in processor engineering is the basis of spatial imaging. Spatial imaging is the main benefit of three-dimensional sonography and it is used for visualization of fetal anatomy in three dimensions. Modern machines are capable of performing spatial imaging in near real time, called four-dimensional sonography. Four-dimensional sonography in multifetal pregnancies can be used for detection and evaluation of intertwin contacts, because it allows simultaneous visualization of both fetuses and assessment of their motor activity. The main benefits of four-dimensional sonography include: accurate recognition of an isolated motor activity of a single fetus; distinguishing between spontaneous and stimulated motor activity; and spatial visualization of the intertwin area. 相似文献