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排序方式: 共有2249条查询结果,搜索用时 265 毫秒
1.
Ishida Takuya Uehara Yoshitoshi Ikeya Tohru Haraguchi Takashi F. Asano Satoshi Ogino Yohei Okuda Noboru 《Limnology》2020,21(3):403-413
Limnology - Controlling phosphorous (P) loads from rice fields is important for the conservation of aquatic ecosystems, in part because P is relatively concentrated at its sources. Recently, winter... 相似文献
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Effects of barbiturates on the inhibitory action of GABA on excitatory response of the stomach to stimulation of vagal afferent fibers in cat 总被引:1,自引:0,他引:1
Effects of barbiturates on the inhibitory action of GABA to the hexamethonium-resistant excitatory response of the stomach to stimulation of the vagal afferent fibers were studied in cats. Inhibition of the hexamethonium-resistant excitatory response by GABA were compared under alpha-chloralose, alpha-chloralose-phenobarbital (PhB), and alpha-chloralose-pentobarbital (PB)-anesthesia in cats. The ID50 of GABA on the hexamethonium-resistant excitatory response was not significantly affected by PhB, but reduced by PB. Both picrotoxin and bicuculline antagonized the effects of GABA. The present experiments demonstrated that PB potentiated the inhibitory effect of GABA on the hexamethonium-resistant excitatory response of the stomach, and suggested that the potentiation by PB may be due to activation of GABA-receptor-ionophore complex. 相似文献
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Hiroshi Taniguchi Takuya Tokida Hiroshi Fujita Hiraku Itikawa 《Molecular & general genetics : MGG》1989,217(2-3):317-323
Summary IndnaK7(Ts) mutant cells, scission of DNA strands occurred after temperature shift up. When cells at 30°C were labeled with [3H]-thymidine and then shifted to 46° or 49°C for 20 min, the profiles of sedimentation of thier cellular DNA in an alkaline
sucrose gradient revealed a decrease in the size of DNA to a quarter of that at 30°C in the mutant, but not in wild-type cells.
The level of manganese-containing superoxide dismutase (MnSOD) in the mutant was about twice that in wild-type cells, even
at the permissive temperature, implying increased production of superoxide radical anion, which may cleave DNA strands directly
or indirectly in the mutant. Moderate increase in the MnSOD level on temperature shift up was observed in both strains. These
results indicated that some components of the DnaK protein participate in protection of cellular membrane functions from thermal
damage resulting from elevated production of the superoxide anion radical. 相似文献
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Atsushi Uchida Takuya Fujimoto Youich Mizutani 《Cancer immunology, immunotherapy : CII》1990,31(1):60-64
Summary During interaction with autologous tumor cells large granular lymphocytes (LGL) of cancer patients released a soluble cytotoxic factor, termed LGL-derived cytotoxic factor, which mediated lysing of autologous fresh tumor cells. The cytotoxic factor was compared with purified human recombinant cytotoxic cytokines, including tumor necrosis factor (TNF), lymphotoxin (LT), interferon (IFN) , IFN, interleukin-1 (IL-1) and IL-2. The LGL cytotoxic factor exhibited cytotoxicity against autologous and allogeneic fresh human tumor cells in an 18-h51Cr-release assay, while these target cells were resistant to lysing by any of the recombinant cytokines. Mixtures of recombinant(r) TNF, rLT, rIFN, rIFN, rIL-1 and rIL-2 were still unable to produce cytotoxic effects on fresh human tumor cells. Treatment with monoclonal and polyclonal antibodies directed against rTNF, rLT, rIFN, rIFN, or rIL-1 did not inhibit the cytotoxic activity of LGL-derived cytotoxic factor against fresh human tumor cells. Even a mixture of all the antibodies was incapable of blocking the cytolytic activity of the factor to fresh human tumor cells. Furthermore, intact LGL-mediated lysing of autologous tumor cells was not inhibited by any of the antibodies. These results may indicate that a cytotoxic factor produced by LGL in response to autologous tumor cells mediates lysing of fresh human tumor cells independently of TNF, LT, IFN, IL-1 and IL-2. 相似文献
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Hiroki Yamaue Hiroshi Tanimura Takuya Tsunoda Makoto Iwahashi Masaji Tani Mikiko Tamai Masaya Inoue 《Biotherapy》1990,2(3):247-259
The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells. 相似文献
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Kazuhisa Toyoda Takuya Sugahara Kunio Inouye Koji Yamada Sanetaka Shirahata Hiroki Murakami 《Cytotechnology》1990,3(2):189-197
An immunoglobulin (Ig) production stimulating factor (IPSF) for hybridomas was found in spent medium of the human B lymphoblastoid cell line, HO-323. The IPSF was purified by serial use of DEAE chromatography, ultrafiltration, gel filtration and HPLC-DEAE chromatography. Purified IPSF was estimated to be a 410 k macro molecule by gel filtration, and contained three types of isomers which were separated from each other by native polyacrylamide gel electrophoresis. All of the isomers were, however, assumed to have the same protein components by SDS polyacrylamide gel electrophoresis.The IPSF was effective for human-human and mouse-mouse hybridomas producing IgM, but not for IgG producers in the experimental condition used here. Human-human hybridoma HF10B4, cultured in IPSF-containing medium, produced 20 times more IgM than in IPSF-free medium under serum-free conditions. The IPSF showed very little proliferation stimulating activity on HF10B4 cells. 相似文献
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The vasoinhibitory effect of NP-252, a 1,4-dihydropyridine derivative Ca++ antagonist, was examined in canine cerebral artery, and this effect was compared with that of nifedipine. NP-252 (10(-7)M) and nifedipine (10(-6) M) nearly abolished the contraction induced by addition of Ca++ to Ca(++)-free medium containing KC1. NP-252 (10(-6)M) and nifedipine (10(-6)M) attenuated the contraction produced by thromboxane A2 agonist (STA2) in normal medium, and the resultant contractions were 22% (n = 6) and 35% (n = 6) of the control contraction, respectively. The vasoinhibitory effects of NP-252 were significantly stronger than those of nifedipine in canine cerebral artery. NP-252 (10(-7) and 10(-6) M) dose-dependently attenuated nifedipine-resistant Ca(++)-contraction in the presence of STA2 in both canine cerebral and coronary arteries. The inhibitory effect of combined treatment with NP-252 (10(-6) M) and nitroglycerin (10(-6) M) on nifedipine-resistant Ca(++)-contraction in the cerebral artery was additive. These results indicate that NP-252 possesses a stronger vasoinhibitory effect than that of nifedipine in canine cerebral artery. 相似文献
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