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101.
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
102.
103.
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
104.
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
105.
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
106.
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
107.
Technical aspects of islet preparation and transplantation 总被引:6,自引:0,他引:6
Jonathan?R.?T.?LakeyEmail author Philip?W.?Burridge A.?M.?James?Shapiro 《Transplant international》2003,16(9):613-632
The introduction of insulin therapy for the management of diabetes mellitus is arguably the greatest milestone in the history of modern medicine. -cell replacement therapy is the only treatment that reestablishes and maintains long-term physiological normoglycemia. Until recently, successful clinical outcomes of pancreas transplantation for patients with long-standing diabetes were much superior to that of islet transplantation. Significant advances in islet isolation and purification technology, the development of more specific and less diabetogenic immunosuppressants and the prophylactic administration of antiviral agents have rekindled a worldwide interest in islet transplantation. This chapter will review the rationale of islet transplantation and the development of islet isolation and purification. The challenges facing clinical islet transplantation in the twenty-first century will also be introduced. 相似文献
108.
Cerebrosides from longan arillus 总被引:5,自引:0,他引:5
From the pulp of Euphoria longana (Longan Arillus), three cerebroside molecular species have been isolated. Six known cerebrosides, soyacerebrosides I and II, 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8E)-2-(2'-lignoceroylamino)-4,8-octadecadiene-1,3-diol (longan cerebroside I) and its 8Z isomer (longan cerebroside II), momor-cerebroside I, and phytolacca cerebroside, were identified as major components of these cerebroside molecular species. All the cerebrosides were shown to be a mixture of geometrical isomers (8E and 8Z) of sphingosine-type or phytosphingosine-type glucocerebrosides possessing 2-hydroxy fatty acids. The structures of these cerebrosides have been determined on the basis of chemical and spectroscopic evidence. 相似文献
109.
海洋药物资源的微生物的分离技术 总被引:19,自引:0,他引:19
海洋微生物是海洋药物的重要资源,资源微生物的分离是开发海洋药物的第一步,本文报道各种资源微生物的分离技术,其包括常规海洋放线菌,细菌和真菌的资源,同样包括极端环境条件下的嗜碱,嗜盐和低的微生物。 相似文献
110.
Subjecting pregnant female rats to situations that activate the hypothalamic-pituitary-adrenal (HPA) axis can have long-term effects on the development of the offspring. Restraint under bright lights is a common method of stressing pregnant females that results in consistent behavioral changes in the offspring. We investigated the effects of gestationally administered restraint, bright lights, and heat on the HPA axis response of 21-day-old offspring following exposure to isolation in a novel environment or under resting conditions. Corticotropin-releasing factor titers in the hypothalamus were unaffected following isolation. Nonetheless, adrenocorticotropin hormone (ACTH) was found to be lower in the gestationally stressed offspring prior to or following the isolation period. Corticosterone was attenuated in gestationally stressed offspring following the postnatal stressor and there was also a tendency for the gestationally stressed females to have lower concentrations of aldosterone. Plasmatic testosterone levels were higher in the gestationally stressed males following the period of isolation. The present data suggest that the HPA axis of the offspring is differentially affected by the gestational stress procedure, that is, it is attenuated at the level of the pituitary and adrenal, but not at the level of the hypothalamus. These data have implications for behavioral differences observed in gestationally stressed animals. 相似文献