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31.
陈汉英 《中国学校卫生》2006,27(12):1049-1050
目的探讨西部少数民族儿童行为问题及其与父母养育方式的关系,为少数民族地区开展心理健康教育提供理论依据。方法采用Achenbach儿童行为量表(CBCL)和儿童抚养行为问卷(CRPR)对415名苗族、土家族和侗族儿童进行调查。结果行为问题检出率为29.63%,其中男童为29.94%,女童为29.25%。男童检出率较高的因子为强迫、抑郁、交往不良、分裂样,女童检出率较高的因子为抑郁、分裂样强迫、多动。男童行为问题的绝大多数因子与父母的拒绝、惩罚定向呈显著的正相关,女童行为问题的多数因子与父母的拒绝呈显著正相关。结论黔东地区少数民族儿童行为问题显著高于全国水平,父母教养方式影响儿童的行为问题。  相似文献   
32.
伴ADHD的对立违抗性障碍儿童行为特征分析   总被引:6,自引:0,他引:6  
目的:了解伴注意缺陷/多动障碍(ADHD)的对立违抗性障碍(0DD)患儿的行为特征。方法:以ICD-10作为诊断标准对门诊就诊儿童进行诊断,得到ODD伴ADHD者40例(64.52%).ODD不伴ADHD者22例(35.48%)。自编家庭情况调查表调查患儿的基本情况。用家长填Achenbach儿章行为量表评定儿童行为。结果:与ODD组相比。合并ADHD组的家长更多对患儿经常打骂和严厉管教:对儿童的不良行为更多地采取打骂的方式。合并组父亲急燥易怒者比ODD组多;合并组起病年龄及就诊年龄比ODD组早:合并组在CBCI。思维、注意问题,违纪、攻击行为,外化性问题,行为总分均高于ODD组。结论:ODD合并ADHD的患儿在思维、注意问题,违纪、攻击行为,外化性问题方面表现更突出,家长对儿童管教方式及不良行为处理方式影响ODD的发生。提示要注重ODD、ADHD的早期干预。  相似文献   
33.
 Hexachlorobenzene (HCB) is still frequently found at elevated levels in human adipose tissue and breast milk. As intoxication with HCB causes neurological disturbance in human beings, the purpose of the present study was to examine neurobehavioral functions in rats after pre- and postnatal exposure. Female rats were fed diets with 0, 4, 8, or 16 mg HCB/kg diet. Exposure started 90 days prior to mating and was continued throughout mating, gestation, and lactation. Thereafter, the offspring were given the same diets as their respective mothers. HCB levels were determined in the brain, the liver, and in the adipose tissue from virgin rats, dams, and the offspring. Concentrations on a lipid basis were found to decline in the order adipose>liver>brain. The exposure levels chosen did not cause gross toxic effects in dams or offspring. There were dose-related increases in liver-to-body-weight ratios in exposed dams, but not in unmated females treated alike. Behavioral testing was conducted in the offspring. Examination of open-field activity on PND 21, and of active avoidance learning on PND 90 failed to reveal significant differences between groups. Training of operant behavior started at the age of 150 days in the offspring from the control, the 8-mg group, and the 16-mg group. Animals were trained on a fixed interval schedule of 1 min (FI-1). On this schedule, responses were reinforced by a food pellet every time 1 min had elapsed after the preceding reinforcement. There were dose-dependent reductions in the post-reinforcement pause, e.g. the time between each reinforcement and the first reaction emitted after it. In addition, the index of curvature, which describes the efficiency of performance on the FI-1 schedule, was decreased in a dose-dependent fashion. Received: 12 April 1994 / Accepted: 26 June 1995  相似文献   
34.
 The behavioral effects of GBR 12909, a selective dopamine uptake inhibitor, were determined in squirrel monkeys trained to respond under a fixed-interval (FI) schedule of stimulus termination and a second-order schedule of IV drug self-administration. Intermediate doses of GBR 12909 increased FI response rate markedly, and the highest dose decreased response rate below control values. The 5HT uptake inhibitors, alaproclate and fluoxetine, and the 5HT agonist, quipazine, attenuated the behavioral-stimulant effects of GBR 12909, whereas the 5HT2A/2C antagonist, ritanserin, enhanced the behavioral-stimulant effects of the lowest dose. GBR 12909 reliably maintained self-administration, and ritanserin increased response rate maintained by the highest dose. The dopamine agonist, quinpirole, increased FI response rate in only one of three subjects, and ritanserin enhanced the behavioral-stimulant effects of quinpirole in that subject. The dopamine agonist, apomorphine, only decreased FI response rate, and ritanserin did not alter its behavioral effects. The pharmacological profile of GBR 12909 administered alone and in combination with selective 5HT drugs in the present study was similar to that obtained previously with cocaine, further demonstrating that 5HT can reliably modulate the behavioral effects of psychomotor stimulants with prominent dopaminergic actions. Received: 9 July 1996 / Final version: 22 November 1996  相似文献   
35.
36.
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   
37.
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   
38.
Activity at 5-HT1 and 5-HT2 receptor sites influences sexual behavior in male and female rats. 5-HT3 antagonists reportedly have no effect on copulatory activity in rats of either sex although they influence a variety of other behaviors. The effects of 5-HT3 agonists on sexual behavior are unknown. The following experiments were undertaken to assess the influence of the 5-HT3 agonists 1-phenylbiguanide (PBG) and 2-methyl-serotonin (2-Me-5-HT) on sexual behavior, when administered intracerebroventricularly. Consistent with earlier reports indicating that 5-HT1 and 5-HT2 receptor activity influences reproductive activity in a sex-dependent manner, PBG was found to facilitate male, but not female, rat sexual behavior. 2-Me-5-HT, however, failed to modify either female or male rat sexual activity. Evidence that PBG, but not 2-Me-5-HT, induces carrier-mediated dopamine release suggests that the effect of PBG in male rats is due to dopaminergic mediation. Overall, the present data indicate that 5-HT3 receptor activation has only slight effects on rat sexual behavior.  相似文献   
39.
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   
40.
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   
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