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51.
Eizi Suzuki 《Journal of plant research》1990,103(3):297-312
In two forest stands, one domonated byAbies spectabilis, and the other byPinus wallichiana-Picea smithiana, 198 cores were taken from 105 conifers in May 1983 and the annual ring widths were measured. The annual ring widths usually
had significant similarities between cores taken from the same tree and with cores taken from different trees. these similarities
increased with tree size. The climatic change affected the large trees more strongly than it did the small trees. Micro environmental
changes, such as canopy gap affected the small trees more strongly. Annual ring widths were also correlated with the annual
precipitations at Jumla 30 km south of the plots for a recent 20 year period. A multiple regression analysis between ring
width and seasonal precipitation showed that the growth ofA. spectabilis was correlated primarily with the rain from May to August and secondarily with that from September to December in the previous
year. 相似文献
52.
Hiroshi Suzuki Hideaki Taguchi Kazuko Nishimura Makoto Miyaji Akira Nakamura Hironori Nakajima 《Mycopathologia》1988,104(1):7-17
Summary The authors succeeded in establishing a murine model of systemic candidiasis being disseminated from the primary gastrointestinal lesions caused by oral inoculation of Candida albicans. Using this model, an attempt was made for detecting the Candida antigen by enzyme-linked immunosorbent assay using avidin-biotin (AB-ELISA) from the serum of infected mice.Gastrointestinal candidiasis was formed in all of the 20 mice treated with the drugs (antibiotics, antineoplastic agents, hydrocortisone, etc.) and inoculated orally with C. albicans. Fourteen of these mice suffered from submucosal candidiasis, and C. albicans was cultured from the visceral organs in 12 of them. The assay by AB-ELISA was able to detect 1.0 ng/ml Candida mannan in the mouse serum. The Candida antigen was detected in the sera of 11 of the 14 mice with submucosal candidiasis. However, the antigen could not be detected in the sera of the 6 mice with intramucosal candidiasis.The assay by AB-ELISA is more sensitive and specific for the diagnosis of systemic candidiasis than other serological assays. 相似文献
53.
Dr. Takashi Yashiro Motonaka Arai Eiko Miyashita Kayoko Yamashita Takuro Suzuki 《Cell and tissue research》1988,251(2):249-255
Summary Snell dwarf mice display remarkable retardation of growth after birth and are known to lack prolactin (PRL), thyroid stimulating hormone (TSH) and growth hormone (GH). The aim of this study was to determine the reason for these hormonal deficiencies. We examined the fine structure of the gland and its immunohistochemical staining pattern with respect to antisera raised against PRL, TSH, GH, adrenocorticotrophic hormone (ACTH) and luteinizing hormone (LH). The gland of control mice reacted immunohistochemically against all antisera used, whereas only ACTH-producing cells (ACTH cells) and LH-producing cells (LH cells) were distinguished in the dwarf mice. ACTH cells in dwarf mice varied in cell shape, although they were similar in size to those of controls. The distribution of secretory granules in the cytoplasm varied from cell to cell. LH cells in the dwarf mice showed immature features, having poorly developed rough endoplasmic reticulum and Golgi apparatus. The cells were about half the size of controls, and secretory granules were smaller. In dwarf mice, non-granulated cells were encountered in addition to granulated ACTH and LH cells. Some of them formed small clusters, characteristic cell junctions being found between the cells; they thus appeared to be follicular cells. The above results suggest that hormone deficiency in Snell dwarf mice is a result of a defect in the hormoneproducing cells in the gland. 相似文献
54.
Esaka Muneharu; Imagi Jun; Suzuki Kanichi; Kubota Kiyoshi 《Plant & cell physiology》1988,29(2):231-235
Ascorbate oxidase activity rapidly increased during callus formationfrom pumpkin fruit tissue. The activity reached a maximum at5 days after transfer and then declined. In callus which hadbeen subcultured at about 4-week intervals for more than oneyear, the activity also increased after transfer to fresh mediumand reached a maximum in the early logarithmic phase of growth.Light had little effect on the appearance of ascorbate oxidaseactivity in pumpkin callus. In the callus grown in the presenceof 10µM CuSO4, the activity was about 10 times that inthe presence of 0.1 µM CuSO4, suggesting that the formatonof ascorbate oxidase in pumpkin callus is stimulated by copper,a prosthetic metal of the enzyme. From 45 to 75% of the totalascorbate oxidase activity in pumpkin cell suspension cultureswas found in the medium. Ascorbate oxidase activity in the medium,as well as that in the cells, increased soon after transferto fresh medium, and reached a maximum at about 5 days. (Received July 2, 1987; Accepted November 21, 1987) 相似文献
55.
H Suzuki Y Kondo A D Carlos J C Seidel 《The Journal of biological chemistry》1988,263(22):10974-10979
The effects of ionic strength, MgATP, and phosphorylation on the degradation rates of heavy meromyosin (HMM) by papain have been compared to their effects on the sedimentation coefficient (s20,w) to determine the relationship of the degradation rate to the equilibrium between the flexed and the extended forms (Suzuki, H., Stafford, W. F., Slayter, H. S., and Seidel, J. C. (1985) J. Biol. Chem. 260, 14810-14817). At 0.025 M NaCl, where HMM is predominantly in the flexed form, MgATP, Mg-adenylyl imidodiphosphate or MgADP reduce kH by 80-90%. MgATP exerts its optimal effect at this ionic strength, where at least 70% of HMM is flexed in the presence or absence of MgATP, suggesting that nucleotides reduce kH by decreasing the proteolytic susceptibility of the flexed form. At 0.5 M NaCl, where HMM is in the extended form, MgATP has no effect on kH. At low ionic strengths phosphorylation decreases kH but increases it in the presence of MgATP. Plots of kH against s20,w determined at various ionic strengths are linear, the data for phosphorylated and dephosphorylated HMM falling on the same line. Thus, raising the ionic strength or phosphorylating the 20-kDa light chain appears to alter kH by increasing the fraction of HMM in the extended form. The degradation rate of the 20-kDa light chain (kL) of dephosphorylated HMM responds to changes in ionic strength in essentially the same way as does kH, suggesting that the response of kL to changes in ionic strength can also be attributed to conversion of HMM to the extended form. However, kL for phosphorylated HMM measured in the presence of MgATP exhibits very little dependence on ionic strength. 相似文献
56.
K Yamashita K Umetsu T Suzuki Y Iwaki T Endo A Kobata 《The Journal of biological chemistry》1988,263(33):17482-17489
The carbohydrate binding specificity of Allomyrina dichotoma lectin II was investigated by analyzing the behavior of various complex type oligosaccharides and human milk oligosaccharides on an A. dichotoma lectin II-agarose column. Basically, the lectin interacts with the Gal beta 1----4GlcNAc group. Substitution of their terminal galactose residues by Neu5Ac alpha 2----6 will enhance their affinity to the lectin. By contraries, substitution at the C-2 or C-3 position of their terminal galactose with other sugars including sialic acid deprives their affinity to the lectin. With this characteristic, the immobilized lectin column can be used to separate complex type oligosaccharides with the Neu5Ac alpha 2----6Gal beta 1----4GlcNAc group from their isomeric oligosaccharides with the Neu5Ac alpha 2----3Gal beta 1----4GlcNAc group, where Neu5Ac is N-acetylneuraminic acid. 相似文献
57.
Detection of fimbriae and fimbrial antigens on the oral anaerobe Bacteroides gingivalis by negative staining and serological methods 总被引:6,自引:0,他引:6
Y Suzuki F Yoshimura K Takahashi H Tani T Suzuki 《Journal of general microbiology》1988,134(10):2713-2720
We screened 63 clinical isolates of Bacteroides gingivalis from eight different laboratories for the presence of fimbriae by negative staining and by immunological methods. Techniques used were bacterial agglutination, Ouchterlony immunodiffusion and Western immunoblotting analysis using rabbit anti-fimbriae and anti-fimbrilin sera raised against fimbriae and fimbrilin (a constituent protein of B. gingivalis fimbriae) from B. gingivalis strain 381. In 49 of the 51 strains tested, fimbriae were clearly detected by negative staining, and 30 (60%) of the fimbriate strains were positive in all three of the immunological assays. A total of 37 strains (75%) were positive by immunoblotting analysis, which was the most reliable of the serological methods used in this study. The study shows that the majority of B. gingivalis strains are fimbriate, and that these fimbriae are immunologically related to the fimbriae of B. gingivalis strain 381. Molecular heterogeneity of fimbrilin was discovered by the immunoblotting analysis, when different strains were compared. With most of the strains, including strain 381, the antifimbrilin serum reacted with a protein of apparent molecular mass 43 kDa, but with 15 strains the immuno-reactive protein had an apparent molecular mass of 46 kDa. 相似文献
58.
Dual regulation of resistance against Toxoplasma gondii infection by Lyt-2+ and Lyt-1+, L3T4+ T cells in mice 总被引:29,自引:0,他引:29
Studies were performed to attempt to define the T cell subset responsible for resistance to Toxoplasma gondii. A temperature-sensitive mutant (ts-4) strain of T. gondii was used for immunization because it causes infection but does not persist in the host. Immunization with this strain induced marked resistance against lethal challenge infection with virulent strains of T. gondii in mice. The resistance could be transferred to normal recipient mice by i.v. injection of spleen cells from ts-4-immunized mice. Marked inhibition of cyst formation in the recipient mice was also noted. The protective activity of immune spleen cells was removed by pretreatment of the spleen cells with anti-Thy-1.2 and C, indicating that T cells are responsible for the observed protection. Pretreatment of immune spleen cells with anti-Lyt-2.2 and C completely ablated their protective effect; pretreatment with anti-Lyt-1.2 or anti-L3T4 and C had lesser effects on their ability to transfer resistance. The effect of anti-Lyt-1.2 was the same as that obtained with anti-L3T4. This suggested that one T cell subset that is partially responsible for protection has both Lyt-1.2 and L3T4 markers on the cell surface. These results indicate that there are substantial roles for both the Lyt-2+ and Lyt-1+, L3T4 T cell subsets in dual regulation of resistance against toxoplasma infection and that Lyt-2+ T cells are the principal mediator of the resistance. 相似文献
59.
NaF-induced Ca2+ mobilization is dependent upon the culture density in a parathyroid hormone-responsive osteoblast-like cell line 总被引:2,自引:0,他引:2
The effect of NaF on cytosolic free Ca2+ concentrations [( Ca2+]i) was examined in a clonal osteoblast-like cell line (MOB 3-4) loaded with Fura 2. MOB 3-4 cells in a sparse culture, which exhibited neither alkaline phosphatase (ALP) activity nor the response to parathyroid hormone (PTH), responded to NaF (0.1-10 mM) to increase [Ca2+]i transiently. In contrast, the cells in a dense culture, which exhibited both ALP activity and the response to PTH, responded to NaF (above 4 mM) to increase [Ca2+]i slowly. [Ca2+]i in osteoblasts in primary culture slowly increased in response to both NaF (above 4 mM) and PTH (3 U/ml). Thus, the sensitivity and the response of MOB 3-4 cells to NaF and PTH varied with the culture density, and high culture density matured the cells like osteoblasts in primary culture. These NaF-induced Ca2+ mobilizations were not dependent upon external Ca2+ and were enhanced by Al3+ (1 microM), whereas the PTH-induced Ca2+ mobilizations were due to Ca2+ influx. These results suggest that the maturation of MOB 3-4 cells, dependent upon the culture density, modulates intracellular signal transduction pathways and thereby alters the NaF-induced Ca2+ mobilization, and that the culture density must be taken into consideration in studying Ca2+ mobilization in such an osteoblast-like cells line as MOB 3-4 cell line. 相似文献
60.
Studies of Sl/Sld in equilibrium with +/+ mouse aggregation chimaeras. II. Effect of the steel locus on spermatogenesis 总被引:3,自引:0,他引:3
H Nakayama H Kuroda H Onoue J Fujita Y Nishimune K Matsumoto T Nagano F Suzuki Y Kitamura 《Development (Cambridge, England)》1988,102(1):117-126
Mutant mice of Sl/Sld genotype are deficient in melanocytes, erythrocytes, mast cells and germ cells. Deficiency of melanocytes, erythrocytes and mast cells is not attributable to an intrinsic defect in their precursor cells but to a defect in the tissue environment that is necessary for migration, proliferation and/or differentiation. We investigated the mechanism of germ cell deficiency in male Sl/Sld mice by producing aggregation chimaeras from Sl/Sld and +/+ embryos. Chimaeric mice with apparent white stripes were obtained. Two of four such chimaeras were fertile and the phenotypes of resulting progenies showed that some Sl/Sld germ cells had differentiated into functioning sperms in the testis of the chimaeras. In cross sections of the testes of chimaeras, both differentiated and nondifferentiated tubules were observed. However, the proportions of type A spermatogonia to Sertoli cells in both types of tubules were comparable to the values observed in differentiated tubules of normal +/+ mice. We reconstructed the whole length of four tubules from serial sections. Differentiated and nondifferentiated segments alternated in a single tubule. The shortest differentiated segment contained about 180 Sertoli cells and the shortest nondifferentiated segment about 150 Sertoli cells. These results suggest that Sertoli cells of either Sl/Sld or +/+ genotype make discrete patches and that differentiation of type A spermatogonia does not occur in patches of Sl/Sld Sertoli cells. 相似文献