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91.
The enigmatic nature of the experience of self-awareness is examined in the light of recent discoveries and, on this basis, combined with inferences derived introspectively from the experience of the phenomenon itself; a specific physical locus of this experience within the human brains is deduced-proposed. The fundamental premise in this work is that whereever conscious self-awareness is generated, the neuronal structure(s) involved must continually have access to an extremely precise representation of information derived from the sense of vision plus a great variety of other kinds of information so as to permit it to make decisions regarding actions (movements and their implementation) that promote the survival and perpetuation of the biological system in which the self is generated. First, a definitve set of criteria that define most of the inputs to and operations carried out by the self-awareness entity were assembled. This ensemble of functions was then compared with the connections and possible roles of specific neuroanatomical structures described in published literature, particularly the recent literature and particularly that concerned with the sense of vision. It was discovered that only one brain structure receives the prerequisite information from the sense of vision plus information derived from cortical memory stores plus a variety of other relevant sources needed to generate a coherent sense of selfness. This structure is the superior colliculus of the tectum. The superior colliculi not only receive a highly precise retinotopic representation of inputs to the eyes, but also receive inputs from a great variety of other structures, including many areas of the cerebral cortex, vestibular inputs, auditory inputs, "affective" inputs, and inputs that putatively define the positions of the eyes and of the head. This information, it is deduced, not only allows this structure to generate a continuing synthesis of representations of the self-vs.-environment, but also allows a part of it to assess the significance (probable meaning) of these integrated inputs with respect to the selection of an implementation of actions that serve the interests of the physical structure in which the self-experience is generated. The function of memory in this system not only involves the continually updated representation of where the self is with respect to items and objects in its environment, but also provides means through which the relevance of recorded experiences representing the past may be caused to affect the decision-making process.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
92.
The central action of the potential antidepressant drug pizotifen (Sandomigran) was studied in mice, rats and rabbits. Pizotifen in doses up to 10 mg/kg i.p. was ineffective in classic tests for antidepressant activity. It neither antagonized the effects of reserpine in rats (hypothermia, ptosis) nor potentiated the effects of amphetamine (in mice and rats), nialamide or L-dopa (in mice) on locomotor activity. However, its antidepressant activity was found in the despair test in rats.On the other hand, pizotifen inhibited the head twitch reaction induced by L-5-hydroxytryptophan in mice (ED50=0.009 mg/kg, i.p.) and by 5-methoxytryptamine (+tranylcypromine) in rats (ED50=0.45 mg/kg, i.p.). It also antagonized tryptamine-induced clonic convulsions of fore-paws in rats (ED50=0.35 mg/kg, i.p.), and in doses of 5–10 mg/kg s.c. inhibited hyperthermia produced by LSD in rabbits. Finally, pizotifen (0.1–0.3 mg/kg, i.v.) inhibited or abolished LSD- or quipazine-induced stimulation of the hind limb flexor reflex of spinal rats; the above effect was not due to noradrenolytic action of the drug. These results suggest that pizotifen strongly blocks the central postsynaptic serotonin receptors.  相似文献   
93.
A telomian-beagle hybrid has been studied as a possible model for the hyperkinetic syndrome in children. Behavior tests showed that hybrids, like children, exhibit hyperactivity, impulsiveness, and impaired learning. Two groups of hybrid could be differentiated; the behaviour of one improved after amphetamine (responders) while that of the did not (nonresponders). Moreover hybrids were less responsive than beagles to other effects of amphetamine such as stereotyped behaviour and hyperthermia. Measurement of blood levels of amphetamine and its active metabolite p-hydroxyamphetamine (pOA) showed that hybrids form less pOA. We propose that the lesser response of hybrids to toxic effects of amphetamine is due to this difference in amphetamine metabolism. Responders showed higher peak blood levels of amphetamine than nonresponders and their improvement on amphetamine correlated with blood levels of amphetamine.Therefore high levels of amphetamine appear to be necessary for its paradoxical effect in this model. This suggests that amphetamine acts by activating both noradrenergic and dopaminergic neuronal systems in the CNS.  相似文献   
94.
第二信使系统和其介导的基因表达对针灸效应影响的研究   总被引:2,自引:0,他引:2  
从微观水平研究针灸效应对揭示其机理有重要的意义。本文从第二信使系统和其介导的基因表达对针灸效应影响的研究方面综述了针灸效应的终结反映于细胞内生物效应的变化(即对机体不同器官组织细胞内的物质代谢调节 ) ,从一个侧面提示 ,针灸对机体各系统的调节作用最终是在细胞通过胞内信息传导系统实现的  相似文献   
95.
鹿茸口服液促进RNA和蛋白质合成作用的研究   总被引:1,自引:0,他引:1  
目的:研究鹿茸口服液对青年及老年小鼠RNA和蛋白质合成的作用。方法:观察口服鹿茸口服液对小鼠肝RNA和蛋白质含量及^3H-Uridine和^3H-Leucine掺入的影响。结果:鹿茸口服液可明显增加老年小鼠肝RNA和蛋白质含量及[^3H]Uridine和[^3H]Leucine掺入RNA和蛋白质,作用明显强于青年小鼠。结论:鹿茸口服液对老年小鼠RNA和蛋白质合成有明显促进作用。  相似文献   
96.
目的 观察博宁霉素霜剂对牛乳头瘤病毒所致奶牛乳头瘤的疗效。方法 将临床患病牛随机分为2组每次将药物和基质分别涂于试验牛及对照牛乳头皮肤的肿瘤上,每日3次,连续进行10d。结果 试验组2例指状乳头状瘤分别于第6天和第9天完全脱落;4例扁平瘤虽未脱落,但瘤体表面均发生明显的剥蚀;对照组均未发生此类现象。结论 博宁霉索霜剂对奶牛乳头的皮肤无损害作用,但可选择性地使指状乳头瘤脱落,扁平瘤剥蚀、脱皮,呈现良好的治疗作用。  相似文献   
97.
鼓室置管治疗儿童分泌性中耳炎疗效观察   总被引:5,自引:1,他引:5  
目的 探讨鼓室置管治疗儿童分泌性中耳炎(SOM)的疗效和并发症。方法 回顾性分析了我科1997年~2001年经鼓室置管治疗的45例(78耳)儿童SOM的临床资料。结果 45例随访1-2年,85%耳(35例,66耳)听力明显改善,鼓室导抗图恢复成A型。结论 积极改善咽鼓管功能并适当延长留管时间,防止过早脱管对提高儿童SOM的治愈率有着积极的意义。  相似文献   
98.
孙宏硕  冯中平 《中国药学》2004,13(4):282-284
Selective cyclo-oxygenase-2(COX-2) inhibitor, VI-OXX(rofecoxib), was voluntarily withdrawn worldwide from drugstores by its maker Merck & Co., Inc. on Sep-tember 30, 2004, for its potential lethal side effects of heart attack or stroke.  相似文献   
99.
In the present paper, the authors review some major effects of acupuncture in the treatment of clinical diseases and sum up some results of experimental researches on the mechanisms of acupuncture. Up to now, clinical practice and experimental researches demonstrate that acupuncture possesses good analgesic effect, integrative regulation effect on the functional activities of the body and  相似文献   
100.
In the present paper, the author makes some comments on the holistic action of acupuncture from the regulative effect on the nerve-endocrine-immune network, and the close relationship between the nerve-endocrineimmune network and the meridian-collateral system of TOM. The wholism concept of TOM refers to the organism being an integrated entirety, and the regulatory effect of acupuncture on functional activities of the organism relies on the integral connection of the acupoint--meridian-collateral-zangfu-organ system. When stimulated with acupuncture, the human body will brings its potential force into full play in preventing and treating diseases.  相似文献   
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