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1.
The effects of the lesion of the postcommissural part of the septum on behavior of the rat has been studied. Results may be summarized as follows. An increase in the exploratory behavior in the open field which decreases rapidly; a decrease in the number of defecations in this test and a decrease in time leaving a dark environment for exploration. In the shuttle box test, no facilitation of the acquisition, but a permanent and quite significant increase in the intertrial activity has been found. We conclude that the lesions tend to decrease the emotivity of the subjects. An interpretation on the basis of the species -- specific defensive reactions explains the transitory and permanent effects of the lesions on the spontaneous activity.  相似文献   

2.
The effect of amtizol, a blocker of the inactivation of calcium-dependant potassium channels of the outward current, on the spontaneous and evoked impulse activity of these cells was investigated in experiments on Retzius neurons of the leech. It was demonstrated that the extracellular application of amtizol induces a decrease in the amplitude and an increase in the duration of evoked AP, while not exerting a perceptible influence on the form of the spontaneous AP. In addition, disruption of the development of the process of habituation that develops in the norm during high-frequency synaptic activation of the neuron is observed in a solution containing amtizol.Translated from Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 78, No. 4, pp. 21–25, April, 1992.  相似文献   

3.
This paper reviews the lifetime contributions of the author to the field of sleep-wakefulness (S-W), reinterprets results of the early studies, and suggests new conclusions and perspectives. Long-term cats with mesencephalic transection show behavioral/polygraphic rapid eye movement sleep (REMS), including the typical oculo-pupillary behavior, even when the section is performed in kittens prior to S-W maturation. REMS can be induced as a reflex. Typical non-rapid eye movement S (NREMS) is absent and full W/arousal is present only after a precollicular section. The isolated forebrain (IF) rostral to the transection exhibits all features of W/arousal and NREMS [with electroencephalographic (EEG) spindles and delta waves], arousal to olfactory stimuli, and including the appropriate oculo-pupillary behaviors. These features also mature normally after neonatal transection. REMS is absent from the IF. After deprivation there is NREMS pressure and rebound in the IF, but the decerebrate cat only shows pressure for REMS. Most IF reactions to pharmacologic agents are within expectations, except for the tolerance/withdrawal effects of long-term morphine use which are absent. In contrast, these effects are supported by the brainstem (i.e. seen in the decerebrate cat). In cats with ablation of the telencephalon, or diencephalic cats, delta waves are absent in the thalamus. EEG thalamic spindle waves are seen triggering S for only 4-5 days after ablation. Therefore, true NREMS is absent in chronic diencephalic cats although pre- and postsomniac behaviors persist. These animals are hyperactive and show a pronounced, permanent insomnia; however, a low dose of barbiturate triggers a dramatic REMS/atypical NREMS rebound. Cats without the thalamus (athalamic cats), initially show a dissociation between behavioral hyperactivity/insomnia and the neocortical EEG, which for 15-20 days exhibits only delta and slower oscillations. Fast, low-voltage W rhythms appear later on, first during REMS, but spindle waves and S postures are absent from the start, such that these cats also display only atypical NREMS. Athalamic cats also show barbiturate-sensitive insomnia. Cats with ablation of the frontal cortices or the caudate nuclei remain permanently hyperactive. They also show a mild, but significant hyposomnia, which is permanent in afrontal cats, but lasts for about a month in acaudates. The polygraphic/behavioral features of their S-W states remain normal. We conclude and propose that: (a) the control of the S-W system is highly complex and distributed, but is organized hierarchically in a well-defined rostro-caudal manner; the rostral-most or highest level (telencephalon), is the most functionally complex/adaptative and regulates the lower levels; the diencephalic/basal forebrain, or middle level, has a pivotal role in inducing switching between S and W and in coordinating the lowest (brainstem) and highest levels; (b) W can occur independently in both the forebrain and brainstem, but true NREMS- and REMS-generating mechanisms exist exclusively in the forebrain and brainstem, respectively; (c) forebrain and brainstem S-W processes can operate independently from each other and are preprogrammed at birth; this helps understanding normal and abnormal polygraphic/behavioral dissociations in humans and normal dissociations/splitting in aquatic mammals; (d) NREMS homeostasis is present in the IF, but only REMS pressure after deprivation persists in the decerebrate cat; (e) the thalamus engages in both NREMS and W; (f) insomnia in diencephalic cats is the result of an imbalance between antagonistic W- and S-promoting cellular groups in the ventral brain (normally modulated by the telencephalon); (g) the EEG waves, which are signature for each S-W state, appear to truly drive the concomitant behaviors, e.g. a hypothetical human IF could alternate between behavioral NREMS and W/arousal/awareness; (h) a role for REMS is to keep the individual sleeping at the end of the self-limiting NREMS periods. The need for accelerating research on telencephaling NREMS periods. The need for accelerating research on telencephalic S-W processes and downstream control of the lower S-W system levels is emphasized.  相似文献   

4.
肱骨结节间沟形态在肱二头肌长头肌腱损伤中的作用   总被引:1,自引:0,他引:1  
目的 提供详尽的肱骨结节间沟形态资料。方法 使用不同地区肱骨 80只 ,将结节间沟分为近侧水平段和远侧垂直段 ,用量角器和卡尺测量二段的长度及其移行处的角度 ;结节间沟的深度和宽度分五个部位测量 ;观察结节间沟的变异和异常。结果 结节间沟近侧段和远侧段的长度及移行处角度分别为 9.4mm、2 9.7mm和 119.9° ;总长度、深度和宽度分别为 39.2mm、0 .7mm和 2 .6mm ;结节上嵴出现率为 11.2 % ,内、外侧骨刺 16 .2 % ,钙化 45 %。结论 肱骨结节间沟的局部形态与肱二头肌长头腱损伤关系密切。  相似文献   

5.
The influence of the level of the transmembrane potential on the dynamics of the extinction of the amplitudes of summary excitatory postsynaptic currents arising in identified giant parietal neurons in response to rhythmic stimulation of the intestinal nerve was investigated in a preparation of the isolated CNS of the common snail in order to identify the possibility of the participation of the postsynaptic element in synaptic plasticity. It was demonstrated that, at a greater value of the transmembrane potential, the decrease in the amplitudes of the postsynaptic currents which have been induced by rhythmic stimulation takes place more rapidly. It was also demonstrated that at a higher frequency of stimulation of the nerve, the effect of the influence of the membrane potential level on the dynamics of the synaptic reactions is more prominent. The data obtained may be regarded as an argument in favor of the possibility of the participation of the post-synapse in plasticity. This study was partially supported by the Russian Basic Research Fund (project No. 94-04-12209). Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 45, No. 1, pp. 171–179, January–February, 1995.  相似文献   

6.
The morphology of the glenoid cavity is highly variable, and no consensus exists regarding how to classify the different forms. We examined 98 dry scapulae to identify a common morphological entity and to define reproducible bony references of the glenoid cavity. The glenoid cavities were photographed perpendicularly in a standardized fashion. The bony peripheral rim was studied on these two-dimensional images, defined by randomly chosen points in order to define one or more circles. This study showed that only the peripheral rim of the inferior quadrants of the articular surface was found to be located on a circle (P=0.926) with a radius of 12.8 mm (SD 1.3 mm). Defining the center of this circle appeared to be more reliable (ICC 0.98) than determining the middle point of the longitudinal axis (0,0) between the most cranial and most caudal points, defined as Saller's line (ICC 0.89). The distance of the center of this projected circle to the middle point of Saller's line had a unimodal distribution, suggesting the existence of only one glenoid cavity morphotype. We then investigated the relationship between the center of the circle and the area of subchondral bone thickening under the bare spot, the so-called tubercle of Assaki. Ten phenolized cadaveric glenoid cavities were examined with computed tomography. A circle was projected on the first image showing the bony peripheral rim, and this circle was copied on the consecutive slices until the tubercle of Assaki came across. The center of the circle was located within the area of the tubercle of Assaki, in all but one specimen. To investigate the clinical implications of this finding, the cadaver specimens were used to compare the position of the center of the circle with the postulated center of implantation according to the literature, and to the reference guide for a commonly used total shoulder prosthesis. The center of the circle was consistently situated more distal than the postulated center of the guide (mean 5.5 mm, range 4–8 mm) and the middle point of the glenoid cavity (mean 2 mm, range 1–3 mm). These findings could offer a reproducible point of reference for the glenoid cavity in osseous anthropometry and a valuable reference in shoulder replacement surgery, and might help in the definition of osseous glenohumeral instability.  相似文献   

7.
The specific character of the relationship of the baseline cellular activity of the caudate nucleus to the features of the impulse activity of the centrum medianum of the thalamus has been identified in chronic microelectrode experiments. Reciprocal changes in the bioelectrical activity were recorded in the first group of cells, with a low action potential repetition frequency, while unidirectional changes with reorganizations in the intralaminar nucleus were recorded in the second. The activation of the cells of the centrum medianum of the thalamus was accompanied during the formation of an instrumental conditioned defense reflex by the formation of a pattern of impulse activity in neurons of the neostriatum which coincided in sign with the reorganizations which were characteristic during the investigation of the baseline activity. It is hypothesized that the features of the internal structure of the caudate nucleus underlie such a relationship. Laboratory of Physiology of Higher Nervous Activity, I. P. Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg. Translated from Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 80, No. 1, pp. 102–108, January, 1994.  相似文献   

8.
A light and electron microscopic study of multiple tumorlets in a 66 year old female is presented. Clinically the patient had had chronic obstructive lung disease with bronchiectasis of the right upper lobe. Aside from severe bronchiectatic alterations, the resected lobe showed typical tumorlets. On electron microscopic study, these were shown to consist of cells containing large numbers of a neurosecretory type of granule, which was identical to those present in the bronchial counterpart of the intestinal argentaffin (Kulchitsky) cell, as well as in pulmonary carcinoid and oat cell carcinoma cells. Our studies suggest the possibility of a histogenetic relationship between tumorlets, bronchial carcinoid tumors, and oat cell carcinoma, the cell of origin in each case being the bronchial counterpart of the intestinal argentaffin cell.  相似文献   

9.
The continuous maintenance of cell adequate function (cellular stress) is considered to be the main feature which characterizes the activity of a live cell. In accordance with the concept of cellular stress, the transition of the cell to the state of adequate funcitoning represents a dual commitment. The cell must function adequately to respond to the demands of the organism and to provide for its own needs. Thus, it is proposed that two systems exist for the regulation of the adequate function of the cell: one enabling the cell to respond to the demands of the organism, and the other providing for the needs of the cell itself. The hormonal system of the organism represents the first of these mechanisms, and I believe that another system exists for regulation of intracellular needs. Adequate function of the cell is determined by the regulative, controlling and defense mechanisms. The balance between the needs of the cell and of the organism should be a concern of physician, since it provides for the optimal function and health of the organism as a whole.  相似文献   

10.
Behavior is not adequately described as a stimulus-response process. It is initiated by the animal and is generated because of its expected outcome in the future. The outcome can be good or bad for the animal. The brain is in charge of the selection process. This is the basic function of the brain. Taking Drosophila as a study case, this paper discusses initiating activity, several examples of outcome expectations, trying out (the internal search for a suitable behavior), chaining of actions, and the functional roles of chance in action selection. It takes mental processes and states such as goals, intentions, feelings, memories, cognition, and attention as higher levels of behavioral control that have their origin in biological evolution.  相似文献   

11.
The mucopolysaccharides of the human Brunner's glands were sulfated by sulfuric acid diluted with acetic anhydride or nitrobenzene (1:50) in 5 min. They were recognized by toluidine blue at a pH of less than 1 by exhibiting a red-violet or violet-red metachromasia. The sulfated radicals were removed by methanol or butanol with HCl, H2SO4, Na or NaOH, aqueous Ba(OH)2 at 60 degrees C, or by acetic anhydride, acetyl chloride, benzoyl chloride, or bromine water at 25 degrees C. The carbohydrates were altered so that sulfation was prevented by prior treatment with aqueous Ba(OH)2, or by acetic anhydride with pyridine at 60 degrees C and by acetyl chloride and by bromine water at 25 degrees C. Periodic acid Schiff staining was prevented by sulfation with a nitrobenzene: H2SO4 mixture but not by an acetic anhydride: H2SO4 combination in 1 h suggesting an additional sulfate radical at hydroxyl sites 1 or 2. Brunner's glands contain a large amount of a neutral mucopolysaccharide and can be used as a model for testing a large number of chemical and blockage reactions. In nearly all instances, Brunner's glands reacted more like pyloric glands than duodenal goblet cells.  相似文献   

12.
The reactions of neurons of the posterior ventral nucleus of the thalamus were investigated during movements of the vibrissae, accomplished independently by the animal, in experiments on rats utilizing a technique of partial curarization proposed by the author. Differences were identified in the pattern of the reactions of the thalamic neurons to deviation of a vibrissa by the experimenter from the pattern of the reactions of the same neurons to deviation of the vibrissa elicited by its hitting against a barrier during a sweep. A dependence of the response of the sensory neurons on whether or not the barrier was mobile during the period of the sweep of the vibrissae was also demonstrated. The hypothesis is advanced that at the thalamic level the analysis of the parameters of the stimulus is accomplished in connection with information regarding movements of the vibrissae.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 77, No. 2, pp. 31–35, February, 1991.  相似文献   

13.
It has been demonstrated in awake rabbits that stimulation of the visual cortex by a solitary pulse of electrical current leads to the formation of a short-latency response in the superior colliculus. The formation of this response is suppressed when a light stimulus precedes it. At the same time, a conditioning solitary electrostimulation of the visual cortex induces a short inhibition of the formation of the response to the test light stimulus. This fact suggests that the influences of the visual cortex on the functioning of the superior colliculus may be biphasic in character. When the adrenergic apparatus of the reticular formation is blocked this inhibitory influence bears a more pronounced and prolonged character. The stimulation of the reticular formation, on the other hand, by means of anodic polarization leads to the diametrically opposite effect: the inhibitory character of the influence of the cortex is replaced by a facilitatory one. The inference is drawn that the character and the directionality of the influence of the visual cortex on the functioning of the superior colliculus is determined to a significant degree by the initial functional state of nonspecific brain systems.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 77, No. 5, pp. 26–34, May, 1991.  相似文献   

14.
The hip joints of 30 human male and female fetuses and stillborns between 20 mm and 350 mm crown-rump length were studied by light microscopy. The ligament of the head of the femur developed in situ as a condensation of mesenchyme at the end of the second month of intra-uterine life (IUL), and was vascularized by branches of acetabular vessels early in the fourth month. In the majority of fetuses older than 5.5 months IUL, vessels in the ligament passed a short way into the femoral head within cartilage canals, to supply a small region around the fovea capitis. The remainder of the head was supplied by vessels in canals from around the upper part of the neck. The ligament changed from predominantly cellular to fibrous during the last 4 months of IUL. This increase in strength suggested significant mechanical functions in utero: limitation of adduction-flexion and opposition to postero-superior dislocation were the most likely.  相似文献   

15.
Summary A biphasic change was seen to occur in the acetylcholine content of the amnion muscular tissue during the development of the chick embryo (5th–13th incubation days). From the 5th to the 8th day the amount of acetylcholine exhibited a considerable rise: from the 8th to 13th day a marked reduction of the acetylcholine content was revealed in the tissue. Within the same period the cholinesterase activity is also seen to change, showing a marked reduction from the 5th to the 8th day, a slight rise on the 11th day, this being followed again by a drop.The change of the acetylcholine content and of the cholinesterase activity is accompanied with reduction of the SH-group concentration in the tissue; a sharp one from the 5th to the 8th day then becoming smoother from the 8th to 13th day. It is pointed out that the changes in the acetylcholine—cholinesterase system are linked with those in the frequency of spontaneous rhythmical contractions of the amnion.(Presented by Active Member AMN SSSR S. E. Severin) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 55, No. 1, pp. 17–21, January 1963  相似文献   

16.
Underlying the epithelium of the vas deferens there is a complex basement membrane showing a thick lamina densa separated from the plasma membrane of epithelial cells by a lamina lucida. On the connective tissue side of the lamina densa, there are plaques composed of a material that is similar to that of the lamina densa but is more compact and has a greater electron density. This material also forms plaques at a short distance from the lamina densa, where it appears as irregular nodular masses. The plaques are bridged by striated anchoring fibrils (SAF) that are variable in structure. Some SAF are long (0.5-0.6 micron) and bilaterally symmetrical, with a central fusiform segment and, on each side, coarsely banded segments. While the fusiform segment presents 5 or 6 diffuse cross striations, the coarsely banded segments show distinct bands labeled B1-B4. Shorter SAF show a coarsely banded segment alone or a coarsely banded segment plus a fusiform segment. Some SAF also branch at the level of the fusiform segments, in which case they form star-shaped structures with three or more branches that have their extremities inserted into plaques. The plaques, as well as the lamina densa, are immunohistochemically reactive to type IV collagen, laminin, and heparan sulfate proteoglycan, whereas the SAF are not immunoreactive to these substances. SAF and plaques, considered as integral components of this basement membrane, form a series of arches or open tunnels traversed by collagen fibrils. It is thus apparent that these elements contribute to the attachment of the basement membrane and the overlying epithelium to the underlying dense connective tissue of the lamina propria.  相似文献   

17.
Prevention of reflux is a major function of the terminal biliary duct system at its junction with the duodenum. We examined this area via scanning electron microscopy and light microscopy to explore anatomic features that might play such a role in the Virginia opossum, a species with a highly developed sphincter of Oddi (SO). The terminal apparatus, most of which consists of a dilated extramural ampulla, has a lumen with abundant folds. Mucus is produced by the lining epithelium and by a plethora of glands. Three muscle layers constitute the SO: an inner longitudinal, an outer circular, and a less consistent, outermost longitudinal. The terminal apparatus forms an acute angle and narrows as it enters the duodenum; at this point, the SO becomes continuous with the muscularis externa of the intestine. Four anatomical features with potential antireflux properties may be identified: mucus production, luminal folds, and the narrow opening and oblique course of the intramural duct.  相似文献   

18.
The structure of hematopoietic marrow of the frog, Rana pipiens, was studied by electron microscopy. Lining cells of the sinus wall lack a basal lamina and are not phagocytic. Phagocytic cells of the marrow are found free in the lumina of sinuses and in the extravascular tissue. Heterophil leucocytes, during their differentiation, possess a single population of granules; mature granules are elongate bodies having a crystalline content. Eosinophil leucocytes also have a single population of granules; the granules are round and have a homogeneous content.  相似文献   

19.
20.
Summary The small intestine, caecum, colon and part of the stomach of guinea-pigs were studied by light microscopy, using semithin sections of plastic embedded specimens. The muscular coat is thicker in the duodenum than in the rest of the small intestine. The ratio between longitudinal and circular muscle is 1:4.6 in the duodenum and it increases regularly along the small intestine, to reach 1:2 in the terminal ileum. In the caecum, shape and sectional area of the muscle tissue were analyzed along the full length of the taeniae. In the caecal circular muscle there is a characteristic change in the arrangement of the muscle bundles from the regions in the centre of the haustrations to the regions of the grooves between haustrations or to those lying beneath a taenia. The functional significance of the taeniae is discussed in terms of an arrangement allowing reduction of the lumen of the organ (which at the level of the grooves between haustrations acquires a triangular outline) more efficiently than if the longitudinal musculature were spread over the entire surface of the organ. Haustrations are present also on one side of the wall of the ascending colon where there is no longitudinal muscle layer. In the descending colon the structure of the wall is examined in different functional states, namely in the regions between fecal pellets (constricted regions) and in the regions around a fecal pellet (moderately distended regions). The musculature increases considerably in thickness in the constricted regions (both muscle layers being actively contracted), while the mucosa and submucosa are thrown into prominent longitudinal folds. These folds produce occlusion of the lumen when the circular muscle has shortened by about 50%.  相似文献   

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