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1.
In 130 cerebral preparations of children and mature persons external structure and dimensions of the temporal operculum, pertaining to the posterior speech cerebral area, have been studied. A great variability in the operculum form, in the number of tertial sulci situating on it, in its linear dimensions and superficial area has been stated. Final dimensions of the temporal operculum are formed in early childhood and have no sex differences. During all age periods, there is a pronounced left-sided tendency in dimensional asymmetry of the temporal operculum dimensions; their predominance in the left side is noticed in more than 70%. No correlation between the operculum surface and the brain mass is revealed, as well as between its surface and the surface of transversal temporal gyri. The left-sided predominance in the length of the lateral sulcus is observed nearly as often as the left-sided prevalence of the temporal operculum, but in a number of cases their asymmetry has an opposite direction. This should be taken into consideration at diagnosing the dominant hemisphere by means of the intravital arteriography and when certain neurosurgical interventions are performed.  相似文献   

2.
The author has investigated the impact of psychological and socio-economic factors on cerebral hemodynamics and development of cerebrovascular disease (CVD). A group of 120 war sufferers with signs of post-traumatic stress disorder and adaptation disturbances, and 120 persons of the control group with no traumatic war experience have been studied. The blood flow velocity and various parameters of spectral frequency analysis have been measured, using the method of transcranial doppler sonography (TCD). A greater number of hemodynamical changes has been found in the group of subjects than in the control group (p < 0.05), in which increase of vasospasm is statistically significant probably as a result of predomination of the sympathetic system stimulation and nicotinic effect on the brain blood vessels. Flow disturbances are relatively more frequent in older subjects, which suggests the rapid development of the atherosclerotic process. The results suggest that exposure to prolonged stress and bad socio-economic factors, through different neurobiological mechanisms, increased the risk for stroke.  相似文献   

3.
The investigation of the external iliac lymph nodes has been performed in 152 preparations of corpses of mature persons of both sex, who died from causes not connected with any disease of the lymphatic system, lower extremities and pelvic organs. The external iliac lymph nodes and their afferent and efferent lymphatic vessels have been revealed by means of interstitial injection of the lower extremities and pelvic organs, as well as by means of direct injection of Gerota mass into the lymphatic vessels. Form, amount, dimensions and topography of common iliac lymph nodes have been studied. Lymphatic vessels, running from certain parts and organs of the body to various subgroups of the external iliac lymph nodes have been described, as well as efferent lymph vessels of these nodes. The external iliac lymph nodes are constant formations; the largest of them--lymph nodes of the lacuna--are nodes of the I step for the lower extremity lymph vessels. In 54% of cases in persons of both sex positive (right-sided) asymmetry has been revealed. Total amount of the iliac lymph nodes prevails in men, while their size is greater in women. The size of these nodes in persons of both sex is greater to the left than to the right. There are connections (in 3% of cases) between the external iliac lymph nodes and aortal and lumbar nodes of the opposite side.  相似文献   

4.
The neural tissue (the hippocamp and septal cerebral area) obtained from rat embryos is transplanted into the anterior eye chamber of mature animals. The developing grafts are sized and measured and light optic microscopy is performed 3-4 months after transplantation. Essential differences in development and organization of the septal cerebral area (SCAG) and the hippocampal (HG) grafts are revealed. The SCAG have a spherical form, a limited contact with the host iris and are vascularized by one--two ingrowing and branching vessels. The HG are elongated in their form, have contacts with the host iris by the wide plane parallel to their long axis and a great number of blood vessels growing into them. The size of the HG is much larger than that of the SCAG. The latter contain diffusely scattered multipolar neurons, while the HG neurons are organized as a layer with their apical dendrites oriented towards the iris.  相似文献   

5.
Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS) as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women). Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.  相似文献   

6.
Contrary to what has often been said about the subject, declinein taste sensitivity with aging characterizes virtually everybodyand is not the artificial result of averaging large losses ofa minority with negligible losses of a majority. This assertionis supported by six repeated measures of sucrose thresholdsin each of 15 older (over 64 years) and 15 younger (under 27years) adult subjects. Threshold was determined by a proceduresimilar to past studies and with the same results: much scatterand considerable overlap between the thresholds of younger andolder subjects. A quite contrasting picture emerges, however,when each subject's six threshold determinations are averaged.Averaging shrinks the individual differences among subjects,as well as the over-lap between younger and older subjects.Although virtually all elderly subjects now revealed taste weakness,reliable individual differences in degree of weakness aboundamong them, suggesting various individual rates of physiologicalaging. In contrast young persons exhibit greater uniformityof sensitivity. These findings were brought out by inter-testcorrelations, which were much higher for the older subjects;i.e. an older subject who tended to score high (low) on onetest tended to score high (low) on the other tests. The studyconfirms the tenuous nature of brief threshold tests as indicesof personal sensitivity as found earlier also in olfactory thresholdsand in concurrent measurement of two-point touch thresholdsin the present study. This revealed correlated losses betweenrepeated taste and touch thresholds from the same 15 older subjects,unrelated to their exact chronological age. Chem. Senses 20:451–459, 1995.  相似文献   

7.
Individual variabilities in form, size and position of the nucleus caudatus head and the putamen have been studied in the horizontal section cutting across the inferior edge of the interventricular foramen (Monro) and the posterior commissure of the cerebrum in 70 mature persons died from various diseases not connected with disorders in the brain. Variability in length, width and position of these strial structures have been estimated taking into account the size of the intercommissural lines. The investigation has demonstrated that with an increasing distance between the anterior and posterior commissures of the cerebrum, the length and width of the nucleus caudatus head and those of the putamen increase; these nuclei are observed to be pushed off the median line and approach towards the level of the anterior cerebral commissure.  相似文献   

8.
The most consistent cognitive sex differences have been found in the visuo-spatial domain, using Mental Rotation (MR) tasks. Such sex differences have been suggested to bear implications on our understanding of autism spectrum disorders (ASD). However, it is still debated how the sex difference in MR performance relates to differences between individuals with ASD compared to typically developed control persons (TD). To provide a detailed exploration of sex differences in MR performance, we studied rotational (indicated by slopes) and non-rotational aspects (indicated by intercepts) of the MR task in TD individuals (total N = 50). Second-to-fourth digit length ratios (2D:4D) were measured to investigate the associations between prenatal testosterone and performance on MR tasks. Handedness was assessed by the use of the Edinburgh Handedness Inventory in order to examine the relation between handedness and MR performance. In addition, we investigated the relation of spatial to systemising abilities, both of which have been associated with sex differences and with ASD, employing the Intuitive Physics Test (IPT). Results showed a male advantage in rotational aspects of the MR task, which correlated with IPT results. These findings are in contrast to the MR performance of individuals with ASD who have been shown to outperform TD persons in the non-rotational aspects of the MR task. These results suggest that the differences in MR performance due to ASD are different from sex-related differences in TD persons, in other words, ASD is not a simple and continuous extension of the male cognitive profile into the psychopathological range as the extreme male brain hypothesis (EMB) of ASD would suggest.  相似文献   

9.
Comparative quantitative analysis of the synaptic pool of the neuropil in the molecular layer at the temporal epilepsy and cerebral chronic hypoxia (brain tumor, that is not accompanied with a convulsive syndrome) has been performed using biopsy material. As a control the brain of practically healthy persons, who died a sudden death, has been used. The contrasting method of the phosphoric tungsten acid alcohol solution and OsO4 has been applied. An essential complication in the cerebral cortex synaptic structure in the zone with a regular epileptic activity, as well as preservation of quantitative density of synapses near to the control level at epilepsy have been revealed. At the chronic hypoxia simplification in organization of interneuronal connections at the level of synapses and reduction in the quantitative density of synapses have been noted. The complication of the cerebral cortex synaptic structure and epileptic changes++ of the brain is considered as an increase in the neuropil informativity, contributing to keeping a long-term memory about the character of epileptic manifestations.  相似文献   

10.
On a sample of 65 subjects rheoencephalography (REG)--the electrical impedance plethysmographic method for assessment of cerebral circulation was applied, as well as an electronic psychodiagnostic instrument Complex Reactionmeter Drenovac (CRD) constructed for assessment of complex psychomotor reactions. The aim of this study was to evaluate the potential differences between subjects with and without signs of cerebral circulatory disorders with regard to speed, stability and accuracy of complex psychomotor reaction. The results revealed that variable "maximal speed" on CRD showed significant difference between the groups, in favor of the control group.  相似文献   

11.
We have recently described frequency-dependent effects of mobile phone microwaves (MWs) of global system for mobile communication (GSM) on human lymphocytes from persons reporting hypersensitivity to electromagnetic fields and healthy persons. Contrary to GSM, universal global telecommunications system (UMTS) mobile phones emit wide-band MW signals. Hypothetically, UMTS MWs may result in higher biological effects compared to GSM signal because of eventual "effective" frequencies within the wideband. Here, we report for the first time that UMTS MWs affect chromatin and inhibit formation of DNA double-strand breaks co-localizing 53BP1/gamma-H2AX DNA repair foci in human lymphocytes from hypersensitive and healthy persons and confirm that effects of GSM MWs depend on carrier frequency. Remarkably, the effects of MWs on 53BP1/gamma-H2AX foci persisted up to 72 h following exposure of cells, even longer than the stress response following heat shock. The data are in line with the hypothesis that the type of signal, UMTS MWs, may have higher biological efficiency and possibly larger health risk effects compared to GSM radiation emissions. No significant differences in effects between groups of healthy and hypersensitive subjects were observed, except for the effects of UMTS MWs and GSM-915 MHz MWs on the formation of the DNA repair foci, which were different for hypersensitive (P < 0.02[53BP1]//0.01[gamma-H2AX]) but not for control subjects (P > 0.05). The non-parametric statistics used here did not indicate specificity of the differences revealed between the effects of GSM and UMTS MWs on cells from hypersensitive subjects and more data are needed to study the nature of these differences.  相似文献   

12.
In 50 cardiac preparations of persons of various age (children, teenagers, adolescents, persons of mature and elderly age) distribution of various branches of the tendinous chordae (basic, marginal, commissural, rough zone) and level of their fixation to the ventricular surface of the right and left cusps of the atrioventricular valves have been studied. The tendinous chordae in direction from the apex of the papillary muscles towards the cusps of the atrioventricular valves are divided into the branches of the 2d--9th orders. Total quantity increase of the tendinous chordae is noted in the mature age, especially those of the 1st order in the left ventricle, and their decrease in the elderly age with an increase of the chordae of the 4th, 5th and 6th orders. Single chordae of the 8th and 9th orders can be found in elderly persons. Certain age specificities are revealed in fixation of various tendinous chordae to the cusps of the atrioventricular valves; they are surely connected with functional peculiarities of their different zones, that ensure air-tightness of the atrioventricular openings. There are quantitative differences of the tendinous chordae, fixed to certain cusps of the left (anterior) and right (anterior, posterior) atrioventricular valves; this is evidently connected with the role of the cusps mentioned in the mechanism of the valves closing.  相似文献   

13.
Modularity of face processing is still a controversial issue. Congenital prosopagnosia (cPA), a selective and lifelong impairment in familiar face recognition without evidence of an acquired cerebral lesion, offers a unique opportunity to support this fundamental hypothesis. However, in spite of the pronounced behavioural impairment, identification of a functionally relevant neural alteration in congenital prosopagnosia by electrophysiogical methods has not been achieved so far. Here we show that persons with congenital prosopagnosia can be distinguished as a group from unimpaired persons using magnetoencephalography. Early face-selective MEG-responses in the range of 140 to 200ms (the M170) showed prolonged latency and decreased amplitude whereas responses to another category (houses) were indistinguishable between subjects with congenital prosopagnosia and unimpaired controls. Latency and amplitude of face-selective EEG responses (the N170) which were simultaneously recorded were statistically indistinguishable between subjects with cPA and healthy controls which resolves heterogeneous and partly conflicting results from existing studies. The complementary analysis of categorical differences (evoked activity to faces minus evoked activity to houses) revealed that the early part of the 170ms response to faces is altered in subjects with cPA. This finding can be adequately explained in a common framework of holistic and part-based face processing. Whereas a significant brain-behaviour correlation of face recognition performance and the size of the M170 amplitude is found in controls a corresponding correlation is not seen in subjects with cPA. This indicates functional relevance of the alteration found for the 170ms response to faces in cPA and pinpoints the impairment of face processing to early perceptual stages.  相似文献   

14.
The ultrasound investigation has been performed by means of the echodevices "Aloka-280" and "Aloka-650" (Japan), transducers of 3.5 and 5 MHz. Eighty-two persons of both sex at the age 16-72 years have been examined. The white line, m. rectus abdominis and m. vastus abdominis have been measured at three levels, as well as lateral amuscular spaces. The width of the abdominal white line is individually very variable; the area of the lateral amuscular spaces is greater to the right than to the left. In 20 persons examined they are absent. The thickness of the m. m. rectus abdominis increases from their superior parts to the inferior ones, and their width just the reverse, decreases in this direction. The state of the anterior abdominal wall muscles has been studied both at rest and under functional load. When the prelum abdominale is at the state of exertion, the muscles react differently: dimensions of the m. m. rectus abdominis at rest and under exertion significantly differ at all levels investigated; the m. m. vastus abdominis become thicker to a less degree. When the prelum abdominale is at the state of exertion, no correlation has been revealed between thickness of the m. m. rectus abdominis and degree of their thickening, as well as between width and manifestation of narrowing. A conclusion is made that the ultrasound method opens great possibilities for vital investigation of the anterior abdominal wall topography.  相似文献   

15.
In the study carried out on children aged 10 years (51 persons), subjects aged 16-17 (11) and adults (19) characteristics of the perception and attention interaction were studied by means of electrophysiological parameters analysis (ERP, CNV, EEG) of the process of solution of various visual tasks. It has been shown that adequate brain provision of this process is based in adults both on the functional topographic differentiation and specialization of separate perceptive operations and on the possibility of controlling generalized and local activating influences according to task requirements. In children aged 10, not differing from the adults by the success of the perceptive activity, age peculiarities of its strategy are revealed connected with functional brain organization. Basic distinctive features of children perceptive activity are intensified regional specificity manifested both in responses to relevant and non-relevant stimuli, and excessive generalized activation testifying to incomplete structural-functional maturation of the frontal regions of the cerebral cortex. Increasing functional activity of these structures in ontogenesis provides for the selectivity of perceptive, cognitive and activating processes, adequate to the requirements of the task.  相似文献   

16.
The arteriolo-venular anastomoses (AVA) in the synovial membrane of the knee joint of fetuses (40), corpses of persons at various age (120) and dogs (30) have been studied by means of the impregnation method after V. V. Kupriyanov. In the synovial membrane shunts and semishunts are revealed. The AVA localize in composition of the deep vascular network of the synovial membrane. They are dynamic structures. The occurrence of their disclosure and their structure depend on the age factor.  相似文献   

17.
Inverse Dynamic calculations are routinely used in joint moment and power estimates during gait with anthropometric data often taken from published sources. Many biomechanical analyses have highlighted the need to obtain subject-specific anthropometric data (e.g. Mass, Centre of Mass, Moments of Inertia) yet the types of imaging techniques required to achieve this are not always available in the clinical setting. Differences in anthropometric sets have been shown to affect the reactive force and moment calculations in normal subjects but the effect on a paediatric diplegic cerebral palsy group has not been investigated. The aim of this study was to investigate the effect of using different anthropometric sets on predicted sagittal plane moments during normal and diplegic cerebral palsy gait. Three published anthropometric sets were applied to the reactive force and moment calculations of 14 Cerebral Palsy and 14 Control subjects. Statistically significant differences were found when comparing the different anthropometric sets but variability in the resulting sagittal plane moment calculations between sets was low (0.01–0.07 Nm/kg). In addition, the GDI-Kinetic, used as an outcome variable to assess whether differences were clinically meaningful, indicated no clinically meaningful difference between sets. The results suggest that the effects of using different anthropometric sets on the kinetic profiles of normal and diplegic cerebral palsy subjects are clinically insignificant.  相似文献   

18.
Comparative ontogenetic investigation of cytoarchitectonics of the cerebral neocortex has been performed in Cetacea and Primates using paraffin frontal and sagittal cerebral sections stained after Nissl. Cerebral hemispheres of dolphins, whales, monkeys and human being have been studied at various periods of prenatal development and in mature individuals. The comparison has been made at similar stages of cytoarchitectonical differentiation of the cortical plate. At two first stages of the prenatal ontogenesis (formation of the cortical plate and its differentiation into layers) there is not any principle differences between the Cetacea and Primates. Peculiarities of the cerebral cortical plate differentiation in the Cetacea (absence of the internal granular layer IV) is determined at the stage of stratification. Similar agranular character of the cerebral cortex differentiation is maintained during the whole subsequent ontogenesis in the Cetacea (heterogenetic type of the neocortex after Brodman). Absence of the layer IV in the cerebral neocortex determines some other principles in the spatial organization of the cortical-subcortical and in the intracortical connections in the Cetacea brain. This is confirmed by modern data of morphological and electrophysiological investigations. Perhaps, a comparatively more simple initial architectonics of the Cetacea brain limited the level of their functional possibilities, the latter is comparable only with anthropoid apes.  相似文献   

19.
A subject of this investigation is the results of the subtotal examination of 4 villages for the detection of heterozygous beta-thalassemic carriers. 848 persons (55.5% of the registered population) have been examined. The mean frequency of the beta-Th gene was 0.0159, FST-Wahlund--0.00975. Statistically significant differences in the gene frequencies between villages have been revealed (p less than 0.01). The study of genetic distances (by Edwards) has revealed no intertribe differences in gene frequencies. The comparison of findings of the present study with other similar investigations enabled to account for the detected differences in the frequencies of beta-thalassemia as a result of the genetic drift. The importance of choosing populations for the study and methods for detection heterozygous beta-thalassemia are discussed.  相似文献   

20.
The evolution of the skin microdepressionary network has been quantified as a function of age on negative replicas by semi-automated image analysis in two populations. The first one was composed of 190 healthy persons from 6 months to 95 years of age. There is a good correlation between the age of the subjects and the 4 stereological parameters of the geometrical figures delimited by the primary and secondary skin folds. Some differences between males and females could be observed concerning the rythm of the evolution of the studied parameters. In a second population of 111 persons (72 females and 39 males) of more than 65 years of age and followed in an epidemiological study ("PAQUID", J. F. Dartigues et al.), we compared the results of the evaluation of the 4 parameters of the cutaneous microdepressionary network with the age of the subjects and with the results of cognitive function tests (MMS of Folstein, Wechsler's test). Some of the stereological parameters seem to be better correlated to the score of MMS than to the chronological age of the subjects.  相似文献   

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