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1.
Genital sensory field: enlargement by estrogen treatment in female rats   总被引:3,自引:0,他引:3  
Recordings of neuronal activity in the pudendal, genitofemoral, and pelvic nerves indicate that the sensory fields of these three nerves are the perineum, the caudal abdomen, and the vagino-cervical area and rectum, respectively. The sensory field of the pudendal nerve was significantly larger in estrogen-treated ovariectomized female rats than in uninjected controls. This effect of estrogen was not mediated by pudendal efferents.  相似文献   

2.
Brief stimulation of the upper lip with the tip of a nylon thread frequently produces an " afterglow" sensation that may persist as long as several minutes after cessation of stimulation. The duration of afterglow is increased by strong suggestion, and decreased by vibration of the skin prior to stimulation. The afterglow may be followed by a period of acute "awareness" of the area, distincty different from the stimulus and afterglow sensations. The afterglows produced by a warm stimulator applied to the back often well up into a painful sting.  相似文献   

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为了解麋鹿雌性生殖系统的组织学结构,应用常规石蜡切片和HE染色技术,对麋鹿卵巢、子宫、输卵管的结构进行了观察。结果显示:麋鹿的卵巢分为皮质和髓质,皮质中含有各级卵泡和黄体,髓质中含有大量的血管;子宫壁从内向外可分为内膜、肌层和外膜,内膜层中分布着大量的腺体和血管,肌层由环肌层和纵肌层构成;输卵管中央有明显的褶皱,管壁包括黏膜层、肌层和外膜。麋鹿雌性生殖系统的组织学结构与其他鹿科动物相似,为进一步研究麋鹿的生殖繁殖提供了参考。  相似文献   

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Classical studies of mammalian movement control define a prominent role for the primary motor cortex. Investigating the mouse whisker system, we found an additional and equally direct pathway for cortical motor control driven by the primary somatosensory cortex. Whereas activity in primary motor cortex directly evokes exploratory whisker protraction, primary somatosensory cortex directly drives whisker retraction, providing a rapid negative feedback signal for sensorimotor integration. Motor control by sensory cortex suggests the need to reevaluate the functional organization of cortical maps.  相似文献   

7.
Cilia in nematode sensory organs   总被引:1,自引:0,他引:1  
Electron microscopic studies revealed thle presenlce of true cilia in nerve processes connected with sensory organs of a nemnatodes. These structures are important in evaluating the relation between nematodes and the other aschelminths, from which they were separated partially on the basis of the supposed total absence of cilia.  相似文献   

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Distributed relaxation processes in sensory adaptation   总被引:7,自引:0,他引:7  
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Self-stimulation alters human sensory brain responses   总被引:3,自引:0,他引:3  
Human electrocortical potentials evoked by self-administered auditory and visual stimuli manifest much smaller amplitude and faster poststimulus timing than do average brain responses evoked by identical machine-delivered stimuli. Auditory evoked potentials show this "self-stimulation effect" to a greater degree than do visual responses. For visual evoked potentials, the effect appears greater at the vertex association area than over the occipital cortex. Individual differences in the magnitude of the "self-stimutlation effect" relate to level of intelligence.  相似文献   

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宽体金线蛭是一种被广泛人工养殖的药用动物,其繁殖力的提高有利于增加养殖者的经济效益,取宽体金线蛭种蛭在室内养殖于自制的水蛭水族箱,取材进行解剖和石蜡切片,观察其生殖系统的形态结构.在宽体金线蛭产下卵茧后,观察其胚胎发育的主要阶段.实验结果表明:(1)宽体金线蛭是雌、雄同体的动物,其雄性生殖系统包括精巢、输精管、贮精囊、射精球、前列腺、阴茎鞘和雄孔几部分,雌性生殖系统包括卵巢、输卵管、蛋白腺、阴道囊和雌孔几部分;(2)宽体金线蛭卵茧产下约3h,受精卵进入二细胞期,约8h进入4细胞期,约12h进入8细胞期,约1d进入多细胞期,约3d进入囊胚期,约5d进入原肠胚期,约28d孵出幼蛭.  相似文献   

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B Diehn 《Science (New York, N.Y.)》1973,181(104):1009-1015
The accumulation of Euglena gracilis in an illuminated region is brought about by two main mechanisms: orientation and subsequent directed movement (positive phototaxis) toward light scattered from particles in the illuminated zone; and by the trapping of cells in this region because of shock reactions experienced upon the cells encountering a sudden decrease of light intensity at the light-dark boundary (inverse photophobic responses).Phototactic orientation is mediated by inverse photophobic reactions which occur when the shadow of the stigma periodically falls upon the photoreceptor proper. Euglena also exhibits shock reactions when an already high light intensity is increased further (direct photophobic responses). The expression of both types of phobic responses depends upon stimulus intensity and adaptation of the sensory system in a seemingly complex way. A definition of the minimum components of the stimulus transduction system and a systems analytical approach to the study of input-output relationships enables one to construct an electronic analog of the cell's signal processing system that converts the photoreceptor input to commands which activate or inhibit flagellar reorientation. Computer simulation studies show that this model has considerable predictive value. It is hoped that with the approach presented in this article, a generalized model has become available for dealing with the questions of sensory transduction in aneural systems. Certainly, at this point more questions have been raised than have been answered. Where is the processing device located? Are its kinetic properties determined by electrical processes or by the rates of chemical reactions? Is the processor, and thereby the behavior of the orgamism, modulated by natural environmental parameters, and can it be modified permanently through more drastic chemical treatment of the cell? Is the system capable of permanent or transitory modification through repeated response, that is, does it exhibit phenomena analogous to learning and memory in higher organisms? These are only a few of the problems that require study in the future.  相似文献   

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Genital infection with herpesvirus hominis type 2 was established in ten female cebus monkeys. Clinical and laboratory findings in the cebus mimic closely those observed in humans, thus providing an experimental model which may be used in the study of the possible role of genital herpetic infection in cervical cancer and in perinatal and chronic neurological diseases.  相似文献   

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应用组织学方法比较观察了猪繁殖与呼吸综合征病毒(PRRSV)弱毒细胞疫苗与灭活疫苗生殖道黏膜免疫的效果。试验选用5月龄长白×大约克夏二元杂交母猪18头。PRRSV弱毒细胞疫苗和灭活疫苗通过生殖道黏膜免疫接种。结果表明PRRSV弱毒细胞疫苗生殖道黏膜接种组母猪的子宫黏膜上皮内淋巴细胞数较灭活疫苗生殖道黏膜免疫接种组和对照组母猪显著减少(P<0.01);而且子宫黏膜上皮变矮变薄,变得有些不规则。灭活疫苗生殖道黏膜接种组母猪子宫黏膜上皮内淋巴细胞数与对照组母猪间差异不显著(P>0.05)。本试验结果显示PRRSV弱毒细胞疫苗经生殖道黏膜免疫接种则对生殖道黏膜上皮内淋巴细胞产生抑制作用。说明PRRSV弱毒细胞疫苗和灭活疫苗经生殖道黏膜免疫效果不理想  相似文献   

17.
Information delivery and the sensory evoked potential   总被引:9,自引:0,他引:9  
The waveform of evoked responses recorded from human scalp is not determined solely by the physical eliciting stimulus, but also varies as a function of the effective information provided by the stimulus. There is a positive component whose latency is determined by the point in time at which ambiguity is reduced, and whose shape and amplitude are influenced by whether it is the presence or absence of an external event which delivers the information.  相似文献   

18.
环境激素2,4-二氯苯酚对家蚕生殖发育的影响   总被引:2,自引:0,他引:2  
为了探讨环境激素对鳞翅目昆虫的影响,用添加2,4-二氯苯酚(2,4-DCP)的人工饲料饲养家蚕,调查2,4-DCP对家蚕生殖发育的影响.结果显示,1.60mmol·kg~(-1)以下浓度的2,4-DCP,对幼虫和蛹的卵巢生长有促进作用(P<0.05);1.60mmol·kg~(-1)的2.4-DCP对5龄后期快速生长阶段的卵巢表现出抑制作用,但在蛹期卵巢的生长获得补偿.高浓度的2,4-DCP对幼虫期、蛹期卵细胞的生长和发育有一定的促进作用(P〈0.01).2,4-DCP对家蚕雄性生殖腺的生长、特别是5龄后期精巢的快速生长期表现出一定的抑制作用,在蛹期抑制作用表现十分强烈,1.60mmol·kg~(-1)的2,4-DCP使雄蛾蚕的精巢几乎完全退化.2,4-DCP使5龄幼虫的精细胞数量微弱减少,至蛹期精细胞和蛾期精子的数量则显著少于对照(P<0.01).1.60 mmol·kg~(-1)的2,4-DCP使雌蛾的产卵数下降到对照的20%,但造卵数比对照高1.3倍,0.80 mmol·kg~(-1)以上浓度的2,4-DCP使不受精卵率显著增高(P<0.05).2,4-DCP主要通过强烈抑制家蚕雄性生殖腺和生殖细胞的发育以表现出很强的雌激素效应.  相似文献   

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ZUBEK JP  WELCH G 《Science (New York, N.Y.)》1963,139(3560):1209-1210
Seven days' exposure to unpatterned light and white noise produced a significantly greater decrease in occipital lobe frequencies than did the same period of darkness and silence. This differential effect may be related to the greater behavioral impairments which seem to occur after prolonged exposure to diffuse light and noise.  相似文献   

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