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1.
2.
T Ryushi T Fukunaga K Yuasa H Nakajima 《European journal of applied physiology and occupational physiology》1990,60(1):44-48
The purpose of the present study was to investigate the influence of muscle fibre composition and stature on fractionated patellar reflex times in ten healthy untrained men (mean age: 23.3 years, SD 3.1; mass: 65.9 kg, SD 8.5; height: 172.3 cm, SD 5.3). Biopsies were taken from the right vastus lateralis muscle. Using staining for myofibrillar adenosine triphosphatase after pre-incubation at pH 4.3 and 4.6, muscle fibres were classified into slow twitch (ST), fast twitch, oxidative-glycolytic (FTa) and fast twitch, glycolytic (FTb) fibres. Total patellar reflex time (TRT) and its fractionated components--reflex latency (LAT) and reflex motor time (MT)--were obtained from the mean of ten trials in each subject whilst performing Jendrassik's maneuvre. The TRT, LAT and MT were 77.7 ms, SD 16.5, 23.4 ms, SD 1.3 and 54.2 ms, SD 16.3, respectively. The LAT was significantly correlated to the percentage number of ST (r = 0.758, P less than 0.05) and FTa fibres (r = -0.657, P less than 0.05), fast twitch:slow twitch ratio (r = -0.799, P less than 0.01) and to the height of the subjects (r = 0.901, P less than 0.001), whereas TRT and MT were not significantly correlated with either fibre types or the height of the subjects. From these results it can be concluded that the LAT during the patellar reflex is influenced by muscle fibre composition and the length of the sensory and/or motor nerve. 相似文献
3.
Gelation Phenomena Induced by Alkali-alcohol Treatment of 7S and 11S Components in Soybean Globulins
Transparent gels containing about 2% protein were obtained by mixing alkaline dope solution of 7S or 11S soybean proteins with alcohol. The 7S component showed the ability to form a stronger gel than the 11S. This phenomenon depended on pH and alcohol concentration. In 66 % ethanol, the viscosity of the 7S and 11S reached maxima at pH 11.4 and 11.2, respectively. Above these pH levels where further unfolding and dissociation into subunits of the protein molecules occur, the viscosity decreased rather. The effectiveness of alcohol to increase viscosity increased in the order; n-butanol < tert-butanol < n-propanol < iso-propanol < ethanol < methanol. Alcohols having minor hydrophobicity were more effective for increasing viscosity, but ethylene glycol was ineffective. The addition of NaCl or 2-mercaptoethanol to ethanol-mixed alkaline dope solutions resulted in the remarkable increment of the viscosity, especially for the 7S. 相似文献
4.
Stimulation of T lymphocyte proliferation by monoclonal antibodies against GD3 ganglioside 总被引:3,自引:0,他引:3
K Welte G Miller P B Chapman H Yuasa E Natoli J E Kunicka C Cordon-Cardo C Buhrer L J Old A N Houghton 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(6):1763-1771
Cell-surface gangliosides are presumed to play a role in cell growth and differentiation. With the use of monoclonal antibodies directed against GD3, a disialoganglioside expressed predominantly by cells of neuroectodermal origin, we have found that GD3 is expressed by a subpopulation of cells of the immune system including: 1) fetal thymocytes in subcortical regions and near vessels, 2) lymph node lymphocytes in interfollicular areas and near vessels, and 3) a small subset of T cells in the peripheral blood. Mouse monoclonal antibodies (two IgGs, one IgM, and F(ab')2 fragments) reacting with GD3 were found to stimulate proliferation of T cells derived from peripheral blood. Proliferation of T cells was observed even in cultures depleted of macrophages, suggesting that activation by anti-GD3 was not dependent on the presence of accessory cells. T cell proliferation was maximum between days 5 and 7 of stimulation and was preceded by expression of interleukin 2 receptors. No stimulation was observed with control antibodies of the identical isotype or with monoclonal antibodies recognizing the gangliosides GD2 or GM2. During stimulation by anti-GD3 monoclonal antibodies, there was an expansion of the GD3+ pool of T cells, but depletion of GD3+ T cells prior to stimulation abrogated the response. Proliferation induced by binding to GD3 could be augmented by exogenous interleukin 2 and phytohemagglutinin. Anti-CD3 (T3) monoclonal antibodies had little or no effect. These results demonstrate that binding to GD3 on the surface of T cells can elicit signals for T cell proliferation. 相似文献
5.
Mikihiko Naito Ichiro Kudo Yukiko Mukai-Sato Susumu Tsushima Hiroaki Nomura Shoshichi Nojima Keizo Inoue 《Cancer immunology, immunotherapy : CII》1987,24(2):158-164
Summary Liposomes composed of chemically synthesized glyceroglycolipids, such as 1,2-dipalmityl-[-cellobiosyl-(1 3)]-glycerol (Cel-DAG), 1,2-dipalmityl-[-lactosyl-(1 3)]-glycerol, or 1,2-dipalmityl-[-maltosyl-(1 3)]-glycerol, were found to enhance protective immunity against transplantable tumor cells (sarcoma 180) in ICR mice. Peritoneal exudate cells prepared from mice treated in vivo with Cel-DAG showed cytostatic activity in vitro against the mouse leukemia cell line, EL-4. Adherent cells separated from this preparation showed similar activity. Peritoneal cells from polypeptone-injected mice acquired appreciable cytostatic activity when incubated in vitro in the presence of glyceroglycolipid liposomes. The adherent cell fraction alone showed rather weak cytostatic activity when pretreated with the glyceroglycolipids, and full activity was restored by supplementing with the nonadherent cell fraction. The ability of glycolipids to induce tumoricidal effects was affected by cholesterol content: with increasing cholesterol content, the activities decreased. Cholesterol-free glycolipid liposomes were taken more efficiently by macrophages than cholesterol-containing liposomes. Cholersterol modifies the surface property of glyceroglycolipid liposomes. Activation of macrophages is responsible for enhancement of protective immunity against tumor cells by injection of these glycolipids in vivo.This work was supported in part by Grants-in-Aid (Nos. 58010010, and 59870076) for Scientific Research from the Ministry of Education, Science and Culture of Japan 相似文献
6.
Orosomucoid (ORM) typing by isoelectric focusing: evidence for gene duplication of ORM1 and genetic polymorphism of ORM2 总被引:2,自引:0,他引:2
Summary It has been demonstrated that the genetic polymorphism of human serum orosomucoid (ORM) is controlled by polymorphic ORM1
and monomorphic ORM2 loci. In this study a Japanese family was encountered in which several members had puzzling electrophoretic
patterns consisting of four bands. The ORM patterns were due to the products of a duplicated ORM1 locus haplotype (ORM1
*
2·1) or the products of new variant alleles at the ORM2 locus. The ORM1
*
2·1 haplotype is very common in the Japanese population, occurring at an allele frequency of 0.16. The increased occurrence of
ORM1 2-1 and the heterogeneity in band intensity among ORM1 2-1 phenotypes could be explained in terms of a duplicated gene
ORM1
*
2·1. The ORM2 locus proved to be polymorphic, with six alleles in the Japanese population.
Dedicated to Professor Dr. K. Nishigami on the occasion of his 60th birthday 相似文献
7.
8.
The electronic structures of newly designed polyimide systems (ethenetetracarboxylic 1,2:1,2-dianhydride-diaminoethyne (PI-A) and ethenetetracarboxylic 1,1:2,2-dianhydride-diaminoethyne(PI-B)) are studied in detail with respect to their optimized geometries on the basis of the one-dimensional tight-binding self-consistent field crystal-orbital method. The computational results have revealed that PI-B shows intriguing properties such as a very small band gap and a wide bandwidth near the frontier level, compared with PI-A and other polyimides. Since PI-B would be a promising candidate for a new electric conducting material, a reaction diagram for this polymer is also proposed.Also affiliated to Central Research Laboratories, Matsushita Electric Industrial Co., Moriguchi 570, Japan. 相似文献
9.
Comparative assessment of the resistance of the unstirred water layer to solute transport between two different intestinal perfusion systems 总被引:1,自引:0,他引:1
The resistance of the unstirred water layer to solute transport was estimated in two different intestinal single-pass perfusion systems for a comparative study, using D-glucose as a model compound. One is a well established perfusion system in anesthetized rats as a standard (system A). The other is the one in unanesthetized rats for comparison (system B). It was demonstrated that in system B as well as in system A the resistance of the unstirred water layer to D-glucose transport should be taken into account and this resistance, accordingly, the effective thickness of the unstirred water layer (delta) which is assumed to be in proportion to its resistance, could be described as a function of the perfusion rate by using a film model. The delta decreased with increasing perfusion rate and was larger in system A than in system B at each perfusion rate; 785 microns in system A versus 319 microns in system B at the perfusion rate of 0.16 ml/min and 337 microns versus 184 micron at that of 2.95 ml/min. Thus in system B the effective thickness, accordingly, the resistance, of the unstirred water layer was reduced to about 50% of that in system A, but the resistance of the unstirred water layer could still account for 85% of the total resistance at the maximum as far as D-glucose absorption was concerned, while 93% in system A. These results suggest that, compared with perfusion experiments in anesthetized rats (system A), the resistance of the unstirred water layer is reduced but cannot be left out of consideration even if perfusion experiments are performed in unanesthetized rats (system B). And the lower resistance of the unstirred water layer in system B was attributed to a turbulent flow in contrary to a laminar flow in system A. 相似文献
10.
The kinetic parameters of a carrier-mediated transport for D-glucose and for taurocholate were determined from rat in situ intestinal single perfusion experiments. The true parameters were obtained by the two-dimensional laminar flow model, in which the solute concentration at the aqueous-intestinal membrane interface can be calculated numerically without assuming the aqueous diffusion layer, discriminating the effects of the unstirred water layer. The true Michaelis constant was 4.5 mM for D-glucose and 1.5 mM for taurocholate. The true maximal transport velocity was 3.4 nmol/s per cm2 for D-glucose and 0.29 nmol/s per cm2 for taurocholate. The apparent Michaelis constant was raised by the factor of 6.6 for D-glucose and 3.6 for taurocholate due to the effects of the unstirred water layer. The maximal transport velocity was relatively unaffected by the unstirred water layer in both compounds. The values of the effective (operational) thickness of the unstirred water layer were compatible with those reported previously by employing various experimental methods. The kinetic parameters obtained in vitro everted sacs, for comparison, almost coincided with the true ones in situ. Therefore, the two-dimensional laminar flow model is shown to be valid not only for determining the kinetic parameters of a carrier-mediated transport in situ but also for predicting the absorption rate in situ from the uptake rate in vitro. 相似文献