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1.
Formation of a Tree having a Low Lignin Content 总被引:2,自引:0,他引:2
Received 30 September 2001/ Accepted in revised form 26 October 2001 相似文献
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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
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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
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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
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Summary Monoclonal antibodies were raised against germinal vesicles which were isolated from fully grown oocytes of the ascidianHalocynthia roretzi. Immunoblot analyses revealed that one of the antibodies, designated Hgv-2, recognized a single band with a molecular weight of about 83 kDa. The antibody, visualized by indirect immunohistochemistry, reacted only with the germinal vesicles of oocytes and did not react with test cells, follicle cells, and other somatic cells of the gonad. During embryogenesis the antigenicity was found in interphase nuclei of all embryonic cells. The antibody did not react with chromosomes or the mitotic apparatus. The antigenicity was retained by interphase nuclei of larval cells, but it disappeared from nuclei of juveniles about 7 days after metamorphosis. 相似文献
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Tadashi Matsunaga Noriyuki Nakamura Naoko Tsuzaki Hiroyuki Takeda 《Applied microbiology and biotechnology》1988,28(4-5):373-376
Summary Among 200 strains of marine bluegreen algae isolated from the coastal areas of Japan, the marine blue-green alga Synechococcus sp. NKBG 040607 excreted glutamate at the highest rate, 82.6% of total amino acids production being glutamate. Synechococcus sp. NKBG 40607 was immobilized in calcium alginate gel. Glutamate production by immobilized cells was double that of native cells. Maximal glutamate production (25 g/cm3 gel per day) of the immobilized cells was observed under a light intensity of 144 Einstein/m2 per second at a cell concentration of 7.5 mg dry cells/cm3 gel. Immobilized cells of Synechococcus sp. can use nitrate as a nitrogen source. Immobilized marine Synechococcus sp. produced 0265 mg/cm3 gel of glutamate for 7 days in the presence of chloramphenicol. 相似文献