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排序方式: 共有1448条查询结果,搜索用时 15 毫秒
1.
A Yabuki S Suzuki M Matsumot M Kurohmaru Y Hayashi H Nishinakagawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(12):1339-1342
The proximal straight tubules of the female mouse kidney exhibit heavy periodic acid Schiff (PAS) staining in their brush borders and numerous cytoplasmic granules. In the present study, the female DBA/2Cr mouse kidney was examined, using various fixatives (formalin, PFA, PLP, Zamboni's, Bouin, or Carnoy solution) and various staining methods (HE, PAS, alcian blue, periodic acid methenamine-silver (PAM), toluidine blue, azan, or Congo red). Under azan and PAM, the staining pattern of the brush border was similar to that of PAS, and few effects of the fixative were observed. Cytoplasmic granules were clearly detected with PAM as well as PAS. However, these granules were not detected with Carnoy solution. Furthermore, distribution of granules differed between PAS and PAM. 相似文献
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ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed. 相似文献
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Y Maruyama Y Suzuki A Kazusaka S Fujita 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(5):493-497
The intracellular dynamics of norsalsolinol, a neurotoxin candidate causing parkinsonism-like symptoms, in PC12 cells was studied. We found that dopamine and norsalsolinol are co-localized to secretory granule layer by sucrose density gradient in norsalsolinol-treated PC12 cells. The norsalsolinol was actively taken up into isolated secretory vesicle fraction from PC12 cells with a Km value of 41.5+/-6.8 microM. The uptake of 10 microM of norsalsolinol was sensitive to reserpine (1 microM), an inhibitor of vesicular dopamine transporter, and dopamine, an endogenous substrate, but insensitive to GBR-12909, an inhibitor of dopamine transporter on plasma membrane. In norsalsolinol-treated PC12 cells, exposure to high K+ or ATP resulted in simultaneous release of norsalsolinol and dopamine. Time course of a release of dopamine and that of norsalsolinol evoked by 50 mM KCl or 100 microM ATP corresponded to each other. These releases were dependent on the concentrations of secretagogues. These data suggest that norsalsolinol is taken up with dopamine into secretory vesicle via vesicular catecholamine transporter. 相似文献
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K Miyahara T Matsumoto S Tose H Sakurai I Igarashi A Saito T Hirose N Suzuki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(1):87-93
Spleen cells from Toxoplasma lysate antigen (TLA)-sensitized BALB/c mice showed the strong cytotoxic activity against both natural killer (NK)-sensitive cells (YAC-1 and RL male-1) and NK-insensitive cells (P-815), when incubated with TLA or recombinant human IL-2 (rhIL-2). The increment of TLA concentration in culture medium increased the cytotoxic activity. Treatment of effector cells; spleen cells from TLA-sensitized mice incubated with TLA, with anti-asialo GM1 or anti-Thy-1 plus complement inhibited the cytotoxic activity of effector cells, whereas treatment with anti-mouse Lyt-2.2 serum plus complement had no effect on the cytotoxic activity. Treatment of spleen cells from TLA-sensitized mice with anti-asialo GM1 and/or anti-Thy-1 plus complement inhibited cytotoxic activities of effector cells. These results suggested that spleen cells sensitized with TLA both in vivo and in vitro were asialo GM1 positive and Thy-1 positive, and the majority of cytotoxic cells induced by TLA were similar to lymphokine-activated killer (LAK) cells induced by IL-2. 相似文献
7.
Pyrethroid carboxyesterase which hydrolyzes the esters of chrysanthemumic acid was purified from rat liver microsome by cholic acid solubilization, ammonium sulfate fractionation, heat treatment, and DEAE-Sephadex A-50 column chromatography. The 45-fold purified enzyme (38% yield) is likely to consist of single protein, as evidenced by polyacrylamide gel disc electrophoresis and Sephadex G-100 column chromatography, and had a molecular weight of approximately 74,000 and a Km of 0.21 mM. It is susceptible to inhibition by organophosphates and carbamate insecticides and insensitive to pCMB, mercuric ion, and cupric ion. It is capable of hydrolyzing trans isomers of synthetic pyrethroids much more rapidly (five to ten times) than the cis counterparts. The purified pyrethroid carboxyesterase is apparently identical in nature with malathion carboxyesterase and with p-nitrophenyl acetate carboxyesterase. 相似文献
8.
Narihito Ogawa Shoya Toyoshima Shinya Sekikawa Masahiro Ishijima Kyosuke Katagiri Chihiro Uematsu Tatsuya Hirano Akihito Ootaka Jun Suzuki 《Journal of Pesticide Science》2023,48(1):11
We investigated the synthesis and herbicidal activity of optically active cinmethylin, its enantiomer, and C3-substituted cinmethylin analogs. Optically active cinmethylin could be obtained in seven steps with the Sharpless asymmetric dihydroxylation of α-terpinene. The synthesized cinmethylin and its enantiomer showed similar herbicidal activity, which was independent of the stereochemistry. Next, we synthesized cinmethylin analogs with various substituents at the C3 position. We found that analogs with methylene, oxime, ketone, or methyl groups at the C3 position show excellent herbicidal activity. 相似文献
9.
Kajiya K Hojo H Suzuki M Nanjo F Kumazawa S Nakayama T 《Journal of agricultural and food chemistry》2004,52(6):1514-1519
(+)-Catechin derivatives with different alkyl chain lengths were synthesized from (+)-catechin and various straight chain alkylaldehydes in the presence of methyl mercaptan, and their antibacterial activities against Gram-positive bacteria were evaluated. The antibacterial activity increased markedly with elongation of the alkyl chain lengths of the derivatives and reached a maximum at a chain of four to seven carbons. Subsequently, interaction of the (+)-catechin derivatives with a model membrane using liposome was investigated. The derivatives with a chain of three carbons or more were found to have very strong affinity for the membrane. The injury action of the derivatives against the membrane was examined with liposome in which calcein was enclosed as a fluorescent indicator. The leakage was observed in the derivatives with chain lengths of four carbons or more. Particularly the derivatives with chains longer than five carbons are considered to destroy the liposome membrane judging from the degree of the fluorescent leakage. These results implied that the lipophilicity and disrupting ability of the (+)-catechin derivatives to the liposome membrane participate in their antibacterial activity. 相似文献
10.
Polyphenol oxidase (PPO) was purified and characterized from Chinese cabbage by ammonium sulfate precipitation and DEAE-Toyopearl 650M column chromatography. Substrate staining of the crude protein extract showed the presence of three isozymic forms of this enzyme. The molecular weight of the purified enzyme was estimated to be approximately 65 kDa by gel filtration on Toyopearl HW-55F. On SDS-PAGE analysis, this enzyme was composed of a subunit molecular weight of 65 kDa. The optimum pH was 5.0, and this enzyme was stable at pH 6.0 but was unstable below pH 4.0 or above pH 7.0. The optimum temperature was 40 degrees C. Heat inactivation studies showed temperatures >40 degrees C resulted in loss of enzyme activity. PPO showed activity to catechol, pyrogallol, and dopamine (K(m) and V(max) values were 682.5 mM and 67.6 OD/min for catechol, 15.4 mM and 14.1 OD/min for pyrogallol, and 62.0 mM and 14.9 OD/min for dopamine, respectively). The most effective inhibitor was 2-mercaptoethanol, followed in decreasing order by ascorbic acid, glutathione, and L-cysteine. The enzyme activity of the preparation was maintained for 2 days at 4 degrees C but showed a sudden decreased after 3 days. 相似文献