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1.
内蒙古赤峰地区鼠疫现状和流行趋势预测及控制措施的研究   总被引:36,自引:0,他引:36  
石杲  马义 《地方病通报》1998,13(4):55-58
赤峰地区于1948 ̄1996年发现了16632.2km^2鼠疫自然疫源地,分布于11个旗(县、区)。目前达到控制鼠疫面积13917.8km^2,占疫源地总面积的83.68%。选取与疫源地相关的12种量经因子进行聚类分析,结果可分为:1.疫源性长存区;2.动物鼠疫间断流行区;3.鼠疫动物病控制区;4.疫源性基本消除区。同时对措施进行了探讨。  相似文献   
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Summary In this report we describe changes in the intracellular redistribution of raf serine/threonine protein kinase (product of the raf proto-oncogene family) in hippocampal neurons following cerebral ischemia in Mongolian gerbils. For immunohistochemical localization studies polyclonal antisera specific for each of the A, B, and Raf-1 isotypes of raf, as well as a pan-raf antisera, were employed. Of these, only sera recognizing B-raf, as well as the general v-raf (raised against the conserved C-terminal region) were positive, indicating that B-raf is the major isotype in this neuronal region. Three different ischemie models were used (repeated 3 times for two min and single 5 or 15 min occlusions, of the common carotid arteries) to demonstrate that ischemie insult causes redistribution of raf protein kinase into the cell nucleus of hippocampal neurons. Increased amounts of raf protein in the nuclei of pyramidal cells following ischemia was confirmed by Western blot analysis of isolated nuclear fractionations. Moreover, an elevation in the level of nuclear raf protein also was detected in the contralateral (i.e. non-occluded hemisphere) neurons of CA1 and CA3 subfields 4 days after the ischemie insult indicating a possible transsynaptic increase in the amount of raf protein along with redistribution. The intranuclear translocation of the immunoreactive material started from the perinucleolar rim and with time extended throughout the nucleus. Enhanced levels and altered redistribution of the raf polypeptide in the nuclei of pyramidal cells of the CA3 subfleld appears to be reversible and returns to the normal level 12 days following the ischemic insult. In addition to triggering the above changes in the intracellular redistribution of raf, ischemie insult also caused an increase in the level of B-raf protein in reactive astrocytes.  相似文献   
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The effects of intracerebral implants of steroid hormones on scent marking in the female gerbil (Meriones unguiculatus) were studied in two experiments. In Experiment 1 various steroids were implanted alone or in combination into the preoptic and anterior hypothalamic area of ovariectomized females. Unilateral implants of testosterone + estrogen, estrogen, estrogen + progesterone, testosterone and testosterone + progesterone stimulated a significant level of marking when compared to controls. Experiment 2 utilized bilateral implants of estrogen dissolved in paraffin in order to explore the distribution hormone sensitive areas in the brain which might be important in the regulation of scent marking in the female gerbil. Pellets of estrogen-paraffin were implanted stereotaxically into either the anterior hypothalamus, preoptic area, septum, hippocampus, thalamus, amygdala or anterior olfactory nucleus of ovariectomized females. Total dosage of hormone implanted was 8.2–8.4 μg. A significant level of marking resulted in animals receiving implants into the anterior hypothalamus, preoptic area and septum when compared to controls. Marking appeared at about the same rate in each of these groups; however, the level of marking attained differed. By the last trial, anterior hypothalamic implanted animals were marking significantly more often than animals in either the preoptic or septum groups. Although there was no evidence of ieakage from the brain, the data suggested that some rapid diffusion of hormone, largely restricted to the brain, was taking place or that the three areas were differentially responsive to the hormone. The data do indicate that some localization of function does exist with respect to regulation of scent marking in the female.  相似文献   
5.
The blood supply to the retina and the lens in 32 gerbils (Meriones unguiculatus) of both sexes from infancy to maturity was studied under light and stereoscopic microscopes, and a scanning electron microscope. Mercox (CL-2R; Dai Nippon Ink, Tokyo, Japan) was injected into the left ventricle of 30 animals in order to visualize the blood supply to the retina and the lens from the ophthalmic artery. The central retinal artery arises from the ophthalmic artery, passes through the papilla of the optic nerve together with the central retinal vein and penetrates the vitreous space (cavity of the eye) between the lens and the internal limiting membrane of the retina, where it divides into the central branches covering the lens and the parietal branches to supply the retina. The former passes through the hyaloid space after branching several arterioles and then covers the lens like a network from its medial and marginal sides. Different from small experimental animals, the parietal branches, just after separating from the central one, divides into the nasal, dorsal and temporal branches in the vitreous space, each of which then subdivides to distribute across the retina on the inner limiting membrane, then delineates the membrana vasculosa retinae. This basal pattern of vasculization 1 day after birth continues to death. Both the central and parietal branches of the central retinal artery correspond to the branches of the hyaloid artery in embryo and the latter is preserved in adult gerbils.  相似文献   
6.
内蒙古中学生神经衰弱患病情况调查   总被引:1,自引:0,他引:1  
目的 :调查研究内蒙古不同民族中学生神经衰弱患病情况。方法 :采用随机整群抽样法 ,对内蒙古八所中学六个民族的中学生进行调查 ,以CCMD -2 -R中神经衰弱标准作最后医学诊断 ,所得数据进行卡方检验。结果 :总患病率为 2 3 5 % ,城市学生患病率高于乡村学生 ,高中生患病率高于初中生 ,均有显著差异 (P <0 0 5 ) ;男女生之间患病率无显著性差异。回族学生患病率最低 ,鄂伦春族学生患病率最高 ,汉族与回族学生之间患病率无显著差异 ,而与蒙古族、鄂温克族、鄂伦春族、达斡尔族之间患病率有显著差异(P <0 0 5 )。结论 :内蒙古中学生神经衰弱患病率较高 ,对来自于城市生、高中生应作为重点防治对象 ,关注少数民族学生的心理健康状况  相似文献   
7.
Stress responses were investigated in 5-month-old male gerbils. Breeders having no pubescent litters served as controls. The first experimental group never left their parents' cage and were thereby fought by higher-ranking males; the second and third groups were stressed for a week by four daily 1-minute encounters with trained fighters, the second group during daytime, the third during the dark period. The first and second groups developed signs of gonadal regression, the third did not. The adrenals of the first group weighed the same as those of controls; the adrenals of both other groups were increased in weight. In the adrenal medulla of all experimental groups, a large number of cells were densely packed with noradrenaline-containing vesicles. In each experimental group the pineal changes included a remarkable decrease in nuclear size of pinealocytes, an increased number of colloidal cysts, and a reduction of that portion of the plasmalemma that is lined by subsurface cisterns. All these changes are interpreted in terms of pineal activation, as are the increased number of membrane whirls found in the first group. The third group exhibited an additional decrease in the size of mitochondria and in the number of "synaptic" structures. This finding and the day-night differences in the gonadal response indicate that stress interferes with the metabolic cyclicity of the pineal gland. However, it remains indiscernible whether the pineal stress reaction signals a general activation of the gland or a change in it's temporal activity patterns.  相似文献   
8.
Summary Gibson (1966, 1979) and Lee (1976) have described the potential usefulness of optic-flow information for the control of locomotion. One variable that might be particularly important for an animal approaching a target is time-to-collision, which Lee argues is most efficiently specified by the tau margin (the inverse of the relative rate of expansion of the target image on the retina). In humans, most empirical studies of optic flow have required perceptual judgements or have examined catching/intercepting behaviours. In animals, most studies have been strictly observational. This is particularly true for mammals, where there has been no experimental work of any kind looking at the control of locomotion. The present experiment demonstrates that the Mongolian gerbil (Meriones unguiculatus) uses time-to-collision information to control deceleration as it runs towards a target. The development of this animal model will aid investigation of the neural circuitry underlying optic flow utilization in motor control.  相似文献   
9.
目的 :研究热休克预处理对脑缺血再灌后热休克蛋白 70 (HSP70 )的表达影响及对缺血神经细胞损伤的保护作用。方法 :采用沙鼠短暂前脑缺血再灌损伤模型 ,光镜观察缺血再灌后神经细胞损伤情况 ,免疫组化方法检测脑缺血后不同时期额叶HSP70蛋白表达。结果 :沙鼠脑缺血后HSP70蛋白仅在再灌后 1d有少量表达 (P <0 .0 1) ;缺血神经细胞在再灌后第 7d大多出现损伤改变 ;热休克预处理能增加沙鼠脑缺血再灌后各期HSP70蛋白表达 (P <0 .0 1) ,明显减轻缺血神经细胞损伤 (P <0 .0 1)。结论 :热休克预处理能通过增加HSP70蛋白表达 ,减少缺血神经细胞损伤。  相似文献   
10.
目的:介绍内蒙古地区最先诊断并治疗肾包虫病患者的临床资料;方法:2例均施行内囊 除术,其中1例为开放性肾包虫,行患肾切除术;结果:近期随访均未复发;结论:B超检查,此病可因包虫内“子囊”、“孙囊”造成“混合性回声超波”;CT扫描本病的囊壁较肾囊肿略厚,并显示特有的“囊中囊”征或囊内窝状分隔;患者Casoni皮内多呈阳性。  相似文献   
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