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Yasuro Yoshimura Takayuki Kawano Mitsuru Kuroi Masaaki Morishita Masahiko Mori Kensaku Kawakatsu 《Histochemistry and cell biology》1970,22(4):337-346
Summary Analysis of lactate and malate dehydrogenase zymograms of rodent salivary glands showed species and organ specific patterns.Lactate dehydrogenase isoenzyme patterns occupied the middle positions in relation to those of skeletal and heart muscle. Activities of the major salivary glands were in the order submaxillary gland>parotid>sublingual gland. Zymogram of the mouse and rat showed LDH4 and LDH5 high activity patterns, while that of the rabbit was the fast moving active one. Hamster salivary gland exhibited a neutral type of the former and the latter.Malate dehydrogenase isoenzyme exhibited very similar patterns for the mouse, rat and hamster. Malate dehydrogenase zymogram of rabbit showed 3 active bands, which was different from the other rodents. 相似文献
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To evaluate the influence of overwintering individuals of zooplankton on spring zooplankton communities, the dynamics of zooplankton
communities with or without overwintering individuals were observed in experimental ponds from fall to spring. An insecticide,
carbaryl, was used to regulate the overwintering individuals. In ponds which received insecticide applications in November
or January, all cladoceran and rotiferan species were eliminated by the treatments and did not reappear until late March or
early April, even when the chemical disappeared rapidly. The low water temperature may delayed the establishment of the populations
from resting eggs. In these ponds, populations of various cladoceran and rotiferan species, which seemed to be originated
from resting eggs, were built up in the spring. In control ponds,Daphnia ambigua orD. longispina overwintered as juveniles and adults and established a large spring population earlier than other cladocerans and rotifers
overwintering as resting eggs. The latter zooplankters did not increase in the spring probably because their growth was suppressed
by the precedingDaphnia species through competition. In nature, even if the number of overwintering individuals is small, they may have a potential
to build up a large population earlier than the individuals hatching from resting eggs. As a result, the species which have
overwintered as individuals seem to predominate in the spring and have a large influence on the spring zooplankton community. 相似文献
47.
Primary production of phytoplankton and secondary production of a daphnid and a chaoborid were studied in a small eutrophic
pond. The gross primary production of phytoplankton was 290 gC m−2 per 9 months during April–December. Regression analysis showed that the gross primary production was related to the incident
solar radiation and the chlorophylla concentration and not to either total phosphorus or total inorganic nitrogen concentration. The mean chlorophylla concentration (14.2 mg m−3), however, was about half the expected value upon phosphorus loading of this pond. The mean zooplankton biomass was 1.60
g dry weight m−2, of whichDaphnia rosea and cyclopoid copepods amounted to 0.69 g dry weight m−2 and 0.61 g dry weight m−2, respectively. The production ofD. rosea was high during May–July and October and the level for the whole 9 months was 22.6 g dry weight m−2.Chaoborus flavicans produced 10 complete and one incomplete cohorts per year. Two consecutive cohorts overlapped during the growing season. The
maximum density, the mean biomass, and the production were 19,100 m−2, 0.81 g dry weight m−2, and 11.7 g dry weight m−2yr−1, respectively. As no fish was present in this pond, the emerging biomass amounted to 69% of larval production. The production
ofC. flavicans larvae was high in comparison with zooplankton production during August–September, when the larvae possibly fed not only
on zooplankton but also algae. 相似文献
48.
Comitogenic effect of solid-phase immobilized anti-1F7 on human CD4 T cell activation via CD3 and CD2 pathways 总被引:14,自引:0,他引:14
N H Dang Y Torimoto K Deusch S F Schlossman C Morimoto 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(11):4092-4100
We have recently developed a mAb, anti-1F7, which defines a family of structures found to include the molecule recognized by anti-Ta1 (CD26). In this paper, we demonstrated that binding of 1F7 by solid-phase immobilized anti-1F7 mAb but not anti-Ta1 mAb has a comitogenic effect by inducing proliferation of human CD4+ T lymphocytes in conjunction with submitogenic doses of anti-CD3 or anti-CD2. The proliferative response induced via the CD3-1F7 or CD2-1F7 pathways is associated with the IL-2 autocrine pathway, including IL-2 production. IL-2R expression and anti-IL-2R (Tac) inhibition. Furthermore, solid-phase immobilization of anti-1F7 but not anti-Ta1 acts in conjunction with submitogenic doses of PMA to mediate a comitogenic effect in the absence of anti-CD3 or anti-CD2, leading to CD4+ T cell proliferation. PMA treatment, in the meantime, leads to enhanced expression of 1F7 on the T cell surface. Despite its functional association with both pathways of activation, however, the 1F7 structure is not comodulated with the CD3/TCR complex nor the CD2 molecule. These findings thus suggest that the CD26 Ag is involved in CD3 and CD2-induced human CD4+ T cell activation. 相似文献
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Vibrio hollisae strains isolated recently from patients in various locations were examined for the presence of the thermostable direct hemolysin gene (tdh) using nucleic acid hybridization and polymerase chain reaction assays. The results were consistent with the previous finding that all strains of V. hollisae carry the tdh gene. In contrast, the tdh gene has been detected in a minority of strains for other Vibrio species (V. parahaemolyticus, V. cholerae non-O1, and V. mimicus). Detailed phylogenetic analysis showed that the tdh genes of the non-V. hollisae species were very closely related to each other and that the tdh gene of V. hollisae was distantly related to the tdh genes of the non-V. hollisae species. These results and the proposed insertion sequence-mediated tdh transfer mechanism suggest that the tdh gene may have been maintained stably in V. hollisae and that the tdh genes of the non-V. hollisae species may have been involved in recent horizontal transfer. 相似文献
50.
Kazushige Morimoto Eisuke Tsuda Ahmed Abdu Said Eriko Uchida Satoshi Hatakeyama Masatsugu Ueda Takao Hayakawa 《Glycoconjugate journal》1996,13(6):1013-1020
Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol–1 of EPO, there was no further increase in their activity over 12.4 mol mol–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO
erythropoietin
- rHuEPO
recombinant human erythropoietin
- hCG
human chorionic gonadotropin
- BHK
baby hamster kidney
- CHO
Chinese hamster ovary
- NeuAc
N-acetyl neuraminic acid
- Gal
galactose
- HRCs
hemolyser-resistant cells
- WST-1
2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na
- IEF
isoelectric focusing
- pI
isoelectric point 相似文献