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31.
Izmaĭlov ChA Korshunova SG Sokolov EN 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2000,50(5):805-818
Human cortical visual potentials (VEP) were studied to obtain electrophysiological data concerning face discrimination and to compare them with the direct estimates of differences between faces obtained in the previous publications. The present schematic faces varied in curvature of a mouth and/or declination of eyebrows. These features determined the emotional expression of the schematic faces. We recorded the VEP as the response to the instant replacement of one schematic face (referent stimulus) by an other one (test stimulus) rather then to presentation of a single stimulus. Thus we recorded direct electrophysiological differences between schematic faces. A characteristic feature of this approach was the application of the set of functionally connected test stimuli with monotonously increasing values of differences between the referent and test stimuli. In a result of analysis the complex of components P120-N180-P230 in sites O1, O2, P3, P4, T5, T6 was described. Interpeaks amplitudes of the components shows high correlations with subjective differences between the same pairs of stimuli as well as with physical (configurative) differences between stimuli measured as the angles of lines, defining curvature of a mouth and a declination of eyebrows. The highest correlation with subjective estimates of emotional differences between faces was shown by interpeaks amplitudes N180-P230 in sites O1 and P3. In the some time the interpeaks amplitudes P120-N180 in sites O1 and T5 reflected highest correlation between configurative measures and subjective estimates of stimuli differences. 相似文献
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33.
Cabbage leaf discs (Brassica oleracea L., Capitata group) were floated adaxial side up in 0, 0.05, or 0.25 m CaCl2 solutions at 15°C for 14 d in the dark. To assess whether the delay of senescence by calcium treatment involved protection of membrane lipids, chlorophyll and protein content and the lipid composition of the membranes were determined during incubation. Chlorophyll and protein content decreased with time, in correlation with a reduction in the amount of phospholipids. The degree of unsaturation of phospholipids and free fatty acids decreased, whereas the ratio of sterol to phospholipid increased. The proportions of phospholipid classes did not change during senescence. The catabolism of phospholipids was delayed by 0.05 m calcium, but accelerated by 0.25 m, as compared to the untreated control. Based on the levels of the lipid intermediates, phospholipase D, phosphatidic acid phosphatase, lipolytic acyl hydrolase, and lipoxygenase appeared to be involved in the breakdown of phospholipids during senescence. Phospholipase D and phosphatidic acid phosphatase may be directly influenced by calcium. The calcium treatment apparently did not affect the activity of acyl hydrolase. Lipoxygenase, responsible for the peroxidation of the polyunsaturated fatty acids, was probably indirectly influenced by calcium. We conclude that the delay of senescence of cabbage leaf discs by calcium treatment involved protection of membrane lipids from degradation. 相似文献
34.
Correlation of neuronal size and peptide immunoreactivity in the guinea-pig trigeminal ganglion 总被引:2,自引:0,他引:2
Summary Frequency and size of guinea-pig trigeminal neurones immunoreactive with antisera to -neo-endorphin(-neo-END), dynorphin A-(DYN), vasoactive intestinal polypeptide-(VIP), somatostatin-(SOM), and substance P-(SP) are reported. Co-localisation of the various peptides to the same ganglion cells was investigated immunocytochemically in consecutive 7-m thick paraffin sections. According to their size, all peptide-immunoreactive neurones belong to the class of small ganglion cells. Within this cell group, SP-immunoreactive neurones appear to be the largest, followed by SOM-, VIP-, -neo-END- and DYN-immunoreactive ganglion cells. The observed differences in size are statistically significant with the exception of that between -neo-END and DYN. This finding correlates well with the observed co-occurrence of the two immunoreactive peptides. All -neo-END-immunoreactive perikarya are also reactive to VIP antisera. These neurones are significantly smaller than those containing VIP-immunoreactivity exclusively. Ganglion cells displaying co-existence of -neoEND- and SP-immunoreactivity or VIP- and SP-immunoreactivity are found too infrequently to allow morphometric analysis. Some non-immunoreactive ganglion cells are shown to be approached by dense baskets of VIP-, -neo-END- or SP-immunoreactive varicose fibres, indicating the presence of intraganglionic modulation sites. The combination of immunohistochemistry and morphometry presented in this study allows the differentiation of diverse populations of primary afferent neurones exhibiting peptide immunoreactivity, most likely reflecting their involvement in different central and peripheral reflex arcs and sensory modalities. 相似文献
35.
Symmetrical dysplasia of the elbow joint and humero-radial synostosis together with brachymesophalangism, shortening of metacarpale I, and synostosis of carpal and tarsal bones in a boy, his mother and most probably also his grandmother is described. The combined malformations resemble closely those reported in a father and his daughter by Joachimsthal and in a father and his son by Mouchet and Saint-Pierre. It is suggested that this may represent a distinct hereditary entity.
Kommissarischer Direktor: Prof. Dr. G. Jentschura 相似文献
Kommissarischer Direktor: Prof. Dr. G. Jentschura 相似文献
36.
Morphometrisch-ultrastrukturelle Untersuchungen am Nucleus supraopticus der Ratte nach Dehydratation
Zusammenfassung Der Nucleus supraopticus der Ratte, die einer Dehydratation ausgesetzt war, wurde ultrastrukturell-morphometrisch analysiert. Dabei zeigte sich, daß die relativen Volumenanteile der einzelnen Zellkompartimente während der fünftägigen Durstperiode eine auffallende Konstanz aufweisen. Hingegen läßt sich eine absolute Zunahme der Einzelzellvolumina und somit auch der an der Synthese und Sekretion der Neurohormone beteiligten Zellkompartimente feststellen. Die vorliegenden Befunde sprechen für einen beschleunigten Abtransport des neurosekretorischen Materials bei gesteigerter Synthese. Auf eine optimale Standardisierung der Perfusionsmethode bei Untersuchungen am neurosekretorischen Zwischenhirnsystem wird hingewiesen.
Morphometric-ultrastructural investigations on the supraoptic nucleus of dehydrated rats
Summary The supraoptic nucleus of the dehydrated rat has been analysed by electron microscopy and morphometry. With that it appears, that the relative volumes of the different cell compartments are striking constant. Otherwise one can see an absolute increase of the cell volume together with the cell compartments which take part at the synthesis and secretion of the neurohormones. These results are expression of an accelerated move of the neurosecretory material during increased synthesis. The importance of an optimal standardization of the perfusion-method in investigations of the neurosecretory system is demonstrated.
Wesentliche Teile der vorliegenden Arbeit werden von H. F. Reinhardt der Medizinischen Fakultät der Universität Basel als Dissertation vorgelegt. 相似文献
37.
Kleine H Wilke R Pelargus Ch Rott K Pühler A Reiss G Ros R Anselmetti D 《Journal of biotechnology》2004,112(1-2):91-95
The intrinsic dc conductivity of long, individual lambda phage dsDNA molecules has been investigated by ultrasensitive low current-voltage-spectroscopy (IV) under ambient conditions and controlled low humidity inert gas atmosphere on microfabricated metal-insulator-metal gap structures. We found a strong dependence of the measured conductivity on the apparent humidity, which we attribute to capillary condensation of water to the immobilized DNA molecules, giving rise to additional ionic currents. Additional IV-spectroscopy experiments under controlled argon atmosphere always revealed a significant drop in electrical conductivity to 4 x 10(-15)AV(-1)microm(-1), indicating almost no considerable contribution of electrical long range charge transport. 相似文献
38.
M. Woiczinski A. Steinbrück P. Weber P. E. Müller V. Jansson Ch. Schröder 《Computer methods in biomechanics and biomedical engineering》2016,19(10):1033-1045
Total knee arthroplasty (TKA) is a successful procedure for osteoarthritis. However, some patients (19%) do have pain after surgery. A finite element model was developed based on boundary conditions of a knee rig. A 3D-model of an anatomical full leg was generated from magnetic resonance image data and a total knee prosthesis was implanted without patella resurfacing. In the finite element model, a restarting procedure was programmed in order to hold the ground reaction force constant with an adapted quadriceps muscle force during a squat from 20° to 105° of flexion. Knee rig experimental data were used to validate the numerical model in the patellofemoral and femorotibial joint. Furthermore, sensitivity analyses of Young’s modulus of the patella cartilage, posterior cruciate ligament (PCL) stiffness, and patella tendon origin were performed. Pearson’s correlations for retropatellar contact area, pressure, patella flexion, and femorotibial ap-movement were near to 1. Lowest root mean square error for retropatellar pressure, patella flexion, and femorotibial ap-movement were found for the baseline model setup with Young’s modulus of 5 MPa for patella cartilage, a downscaled PCL stiffness of 25% compared to the literature given value and an anatomical origin of the patella tendon. The results of the conducted finite element model are comparable with the experimental results. Therefore, the finite element model developed in this study can be used for further clinical investigations and will help to better understand the clinical aspects after TKA with an unresurfaced patella. 相似文献
39.
The Protein Journal - As expected, several new variants of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) emerged and have been detected around the world throughout this Coronavirus... 相似文献
40.
Zazueta C Franco M Correa F García N Santamaría J Martínez-Abundis E Chávez E 《Life sciences》2007,80(14):1252-1258
Massive Ca(2+) accumulation in mitochondria, plus the stimulating effect of an inducing agent, i.e., oxidative stress, induces the so-called permeability transition, which is characterized by the opening of a nonspecific pore. This work was aimed at studying the influence of thyroid hormone on the opening of such a nonspecific pore in kidney mitochondria, as induced by an oxidative stress. To meet this objective, membrane permeability transition was examined in mitochondria isolated from kidney of euthyroid and hypothyroid rats, after a period of ischemia/reperfusion. It was found that mitochondria from hypothyroid rats were able to retain accumulated Ca(2+) to sustain a transmembrane potential after Ca(2+) addition, as well as to maintain matrix NAD(+) and membrane cytochrome c content. The protective effect of hypothyroidism was clearly opposed to that occurring in ischemic reperfused mitochondria from euthyroid rats. Our findings demonstrate that these mitochondria were unable to preserve selective membrane permeability, except when cyclosporin A was added. It is proposed that the protection is conferred by the low content of cardiolipin found in the inner membrane. This phospholipid is required to switch adenine nucleotide translocase from specific carrier to a non-specific pore. 相似文献