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91.
Garris DR 《Brain research》2003,963(1-2):150-155
The relationship between changes in regional brain bioamine levels and the expression of intraspecies aggressive behavior was evaluated in two murine models. In one study, normal male mice were maintained either in aggregate (i.e., normal, intraspecies social behavioral controls) or isolated (i.e., developed, non-social intraspecies aggressive 'fighter' behavior) housing environments, and the accompanying changes in both olfactory tubercle (OT) and hypothalamic (HYPOTH), norepinephrine (NE), dopamine (DA) and serotonin (5-HT) concentration indices quantitated by high-performance liquid chromatography (HPLC) for analysis of behavior-related alterations in localized bioamine deposition loci. Intact mice which had been housed in isolation cages and which exhibited aggressive, intraspecies reflexive-biting ('fighter') behavior when introduced to a novel (stimulus) animal, exhibited significant (P<0.05) elevations in NE levels, and depressed DA concentrations, in the OT regions relative to aggregated controls, indicating an intrinsic social influence on the maintenance of basal adrenergic indices at this neural locus. No changes in 5-HT levels were indicated between control and aggressive, isolated 'fighter' groups in either OT or HYPOTH loci. In addition, the NE and DA levels in the HYPOTH samples of both control and aggressive groups were found to be comparable. In the second study, utilizing an alternate type of aggression-induced murine model, changes in bioamine parameters were determined from samples obtained from aggregated, olfactory-bulbectomized (Obx) mice which are recognized to exhibit an overt, intraspecies, reflexive-biting behavior as compared to sham-operated (control) mice housed under identical conditions. In these studies, Obx-mice exhibited a significant increase in 5-HT levels in the OT relative to sham-operated controls, but similar NE and DA concentrations. In addition, all hypothalamic bioamine indices were found to be comparable between control and Obx groups. These data, collected for both isolation-developed, and experimentally-induced (i.e., OBX), intraspecies aggressive models, indicate that the distinctive types of aggressive behaviors displayed by these two murine models are accompanied by specific alterations in regional bioamine levels within the OT of these groups, relative to controls. These data suggest that the specific type of overt aggressive behavior demonstrated by these models may be causally related to the identified changes in bioamine concentrations in the forebrain regions of the CNS, in loci recognized to participate in environmental recognition and social processing activities. 相似文献
92.
目的了解深圳市非结核分枝杆菌主要分布情况。方法采集深圳市的几家大的市属医院和各区人民医院的处理前后污水以及医院候诊室、病房、输液宣的空调过滤网灰尘,另外采集各区有代表性的居民生活区明沟污水和各区农贸市场的污水(特别是肉类、禽类、鱼类摊挡的污水),进行非结核分枝杆菌培养。结果各样本培养的阳性率,医院污水处理前为87.5%、处理后为37.5%、医院空调为6.3%、农贸市场污水为54.5%、居民区生活污水为70.3%、沫浴场海水为25%、生态区海水为0、沙滩沙为0、宾馆喷泉为12.5%、生活区水景池水为0、居民游泳池水为0、山泉水、井水为0。结论环境非结核分枝杆茵在医院污水、居民区明沟污水、农贸菜场污水存在较多,应引起重视,以便采取有效措施,保护人群的身体健康。 相似文献
93.
乙酸钙-鲍氏不动杆菌临床分离与耐药性的7年监测 总被引:2,自引:2,他引:2
目的了解1998~2004年乙酸钙-鲍氏不动杆菌在临床标本中的分离情况及其耐药趋势,为临床感染的预防和治疗提供参考资料。方法回顾分析1998~2004年间所有标本中乙酸钙-鲍氏不动杆菌的分离率,菌株在标本和病区的分布以及对14种抗菌药物的耐药率。结果乙酸钙-鲍氏不动杆菌的分离率有逐年升高的趋势,从1998年的0.18%增至2004年的1.48%;其在呼吸道标本的分离率最高(70.58%),其次是尿液(9.42%)、血液(4.63%);病区分布以重症监护室最高(47.28%),乙酸钙-鲍氏不动杆菌对14种抗菌药物的耐药率,1998年仅有氨曲南>50%,而到2004年仅头孢哌酮/舒巴坦的耐药率<50%,其他13种均>50%;其耐药率均呈递增的趋势,耐药性增幅列前3位分别为:头孢他啶11.1%~88.9%、亚胺培南0~64.8%、复方新诺明0~64.0%。结论乙酸钙-鲍氏不动杆菌的临床分离率在增加,其对多数抗菌药物有较高的耐药性,且耐药率呈逐年上升趋势,尤其是对亚胺培南耐药率的快速增长,应引起临床抗感染治疗的高度重视。 相似文献
94.
95.
宁波登革热患者血清病毒分离及其E/NS基因片段序列分析 总被引:1,自引:0,他引:1
目的:从病人血清中分离登革热病毒,分析其与国际不同地区流行代表毒株之间的遗传关系。方法:利用C6/36细胞培养方法从早期病人血清中分离登革热病毒,利用RT—PCR方法进行鉴定,扩增E/NS基因片段并测序,将结果与GENBANK中其他登革热1型病毒E/NS基因片段的240bp核苷酸进行比较,用计算机软件分析结果。结果:从早期病人血清中分离到两株登革热1型病毒,其核苷酸片段与亚洲流行株系的GD0599、GZ80、Djibouti和Taiwan87的同源性较高,分别为99.6%、97.5%、95.4%和95%。结论:引起此次宁波登革热疫情的登革热1型病毒属于亚洲株系。 相似文献
96.
97.
Michael K Harte Susan B Powell Lindsay M Reynolds Neal R Swerdlow Mark A Geyer Gavin P Reynolds 《Neuropsychopharmacology》2004,56(4):296-299
BACKGROUND: Isolation rearing of rats is a nonpharmacologic, nonlesion manipulation that leads to deficits in prepulse inhibition (PPI) and other behavioral and neurochemical alterations reminiscent of schizophrenia. N-acetylaspartate (NAA) is present in high concentrations in the central nervous system and is found primarily in neurons. N-acetylaspartate is considered to be a marker of both neuronal loss and cellular dysfunction. Magnetic resonance spectroscopy studies have shown reductions of cortical and hippocampal NAA in schizophrenia, and a recent postmortem study has demonstrated a regionally selective temporal cortex deficit. METHODS: The aim of the present study was to determine whether rats reared in isolation exhibit deficits in PPI and reductions in NAA in discrete brain regions, namely the temporal cortex, frontal cortex, hippocampus, and striatum. RESULTS: Compared with socially housed rats, isolation rearing resulted in PPI deficits (p <.05) and reductions in NAA in the temporal cortex (p <.001), with no significant change in the other regions investigated. CONCLUSION: These results suggest a disturbance of neuronal function, reflected by NAA reductions in the temporal cortex in isolation-reared rats, providing further evidence that isolation rearing can mimic aspects of the neuronal pathology of schizophrenia. 相似文献
98.
孕妇宫颈巨细胞病毒(CMV)排出率为4.12%(8/193)。宫颈排出CMV的母亲所分娩的6名婴儿中有4名受感染,其中1名从唾液和尿排出CMV长达7个月以上。从3名母亲的乳汁分离出CMV,其中1名特续存在1个月以上。3名从宫颈分泌物和乳汁排出CMV者,其婴儿均受到感染。结果表明CMV在母婴之间传播。 相似文献
99.
Custaud MA Belin de Chantemele E Larina IM Nichiporuk IA Grigoriev A Duvareille M Gharib C Gauquelin-Koch G 《European journal of applied physiology》2004,91(5-6):508-515
Confinement and inactivity induce considerable psychological and physiological modifications through social and sensory deprivation. The aim of the SFINCSS-99 experiment was to determine the cardiovascular and hormonal pattern of blood volume regulation during long-term isolation and confinement. Simulation experiments were performed in pressurized chambers similar in size to the volumes of modern space vehicles. Group I consisted of four Russian male volunteers, who spent 240 days in a 100-m3 chamber. Group II included four males (one German and three Russians) who spent 110 days in isolation (200-m3 module). The blood samples, taken before, during and after the isolation period, were used to determine haematocrit (Ht), growth hormone (GH), active renin, aldosterone, and osmolality levels. From the urine samples, electrolytes, osmolality, nitrites, nitrates, cortisol, antidiuretic hormone (ADH), aldosterone, normetanephrine and metanephrine levels were determined. The increase in plasma volume (PV) that is associated with a tendency for a decrease in plasma active renin is likely to be due to decreased sympathetic activity, and concords with the changes in urinary catecholamine levels during confinement. Urinary catecholamine levels were significantly higher during the recovery period than during confinement. This suggests that the sympathoadrenal system was activated, and concords with the increase in heart rate. Vascular resistance is determined by not only the vasoconstrictor but also vasodilator systems. The ratio of nitrite/nitrate in urine, as an indicator of nitric oxide release, did not reveal any significant changes. Analysis of data suggests that the duration of the isolation was a main factor involved in the regulation of hormones. 相似文献
100.
In addition to the cognitive deficits associated with fetal alcohol syndrome (FAS), clinical and animal studies indicate that alcohol exposure might also have detrimental effects on social behavior. In a rat model of FAS, experimental rats were given alcohol from gestational day (GD) 1 to 22 and from postnatal day (PD) 2 to 10, a period roughly equivalent to all three trimesters in humans. Control groups consisted of rats exposed to the administration procedures but not to alcohol and nontreated rats. At 30 days of age, rats were tested for social behavior in an alley maze that contained its cagemate in the goal box. After varying periods of isolation, the animals' latencies to reach the goal box and their social behaviors once inside the goal box were recorded. Alcohol-exposed animals ran faster than control rats to the occupied goal box regardless of the amount of isolation. The alcohol-exposed animals also exhibited aberrant social interactions with their cagemate once inside the goal box compared to one or both of the control groups. Specifically, the alcohol-exposed animals showed greater amounts of anogenital sniffing, chasing, hopping and darting, and retrieving and lesser amounts of pinning and biting compared to one or both of the control groups. The alcohol-induced change in anogenital sniffing varied over increasing amounts of isolation compared to both control groups, but the alterations in the other behaviors did not. It is argued that the altered social behavior of alcohol-exposed animals is not the result of changes in the animals' motivational state or social learning and may be the result of an increased responsiveness to social stimuli. 相似文献