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排序方式: 共有6314条查询结果,搜索用时 15 毫秒
71.
K Ishibashi S Hanada K Uozumi M Otsuka T Sakurami S Hashimoto 《Journal of immunological methods》1989,119(2):217-221
A sandwich enzyme-linked immunosorbent assay (ELISA) for immune complexes of human T cell leukemia virus type I (HTLV-I) was developed using monoclonal antibody (MoAb) 3G1 which recognizes a different epitope on HTLV-I to that with which natural human anti-HTLV-I antibody binds. The assay was capable of titrating artificial immune complexes not only at antigen-antibody equivalence but also at antibody excess. Although the antigen-antibody ratios could not be determined in the individual sera from patients with overt ATL, the level of immune complexes in three out of four sera was estimated to be 250 +/- 36 ng/ml. Immune complexes of HTLV-I could not be identified in sera obtained from one patient with overt ATL, three healthy HTLV-I carriers and three normal human controls. 相似文献
72.
J Hayashi M Hirata K Nakashima A Noguchi S Kashiwagi M Matsui H Ishibashi Y Maeda 《Fukuoka igaku zasshi》1991,82(12):648-654
508 Japanese patients with chronic liver disease, including chronic hepatitis, cirrhosis and hepatocellular carcinoma, and 500 controls matched for sex and age were studied. Antibody to hepatitis C virus (anti-HCV) alone was found in 233 (45.9%) patients and hepatitis B surface antigen (HBsAg) alone was present in 128 (25.2%) patients. Both anti-HCV and HBsAg were present in 18 (3.5%) patients. Anti-HCV was found in 8 (1.6%) controls and HBsAg was present in 4 (0.8%) controls. The prevalence of anti-HCV alone was 36.9% in chronic hepatitis, 49.0% in cirrhosis and 67.0% in hepatocellular carcinoma, respectively. The prevalence of anti-HCV increased with the progress of severity of liver disease. Anti-HCV was more prevalent than HBsAg both in cirrhosis and hepatocellular carcinoma (p less than 0.001). The prevalence of anti-HCV increased with age. Among patients under age 39 years, HBsAg was detected more often than anti-HCV, however, in those over age 50 years, anti-HCV was detected more often than HBsAg (p less than 0.001). It would appear that hepatitis C virus more than hepatitis B virus is a prominent cause of chronic liver disease among Japanese patients. 相似文献
73.
Yoshihiro Kikkawa Hideki Abe Masahiro Fujita Tadahisa Iwata Yoshio Inoue Yoshiharu Doi 《Macromolecular chemistry and physics.》2003,204(15):1822-1831
Direct visualization of crystal growth in poly(L ‐lactide) thin films was carried out by using a temperature‐controlled atomic force microscopy (AFM). At the initial stage of crystallization, edge‐on lamellar crystals have nucleated and elongated. Subsequently, the edge‐on lamellar crystals showed S‐shaped morphology and changed their orientation from edge‐on manner to flat‐on one. The curvature of edge‐on lamellar crystal has been discussed in terms of inclination and distortion of polymer chains in the crystal. In addition, mechanism on the formation of flat‐on crystal from edge‐on lamellae was proposed as derivative growth on the basis of in situ AFM observation of crystal growth and enzymatic degradation.
74.
Suppressive effect of leflunomide metabolite (A77 1726) on metalloproteinase production in IL-1beta stimulated rheumatoid synovial fibroblasts 总被引:2,自引:0,他引:2
Migita K Miyashita T Ishibashi H Maeda Y Nakamura M Yatsuhashi H Ida H Kawakami A Aoyagi T Kawabe Y Eguchi K 《Clinical and experimental immunology》2004,137(3):612-616
Leflunomide, an isoxazol derivative structurally unrelated to other immunomodulatory drugs, has proven to be efficacious in the treatment of rheumatoid arthritis (RA). This study was conducted to elucidate the mechanism by which leflunomide mediated antirheumatic effects. We investigated the effects of A77 1726, leflunomide's active metabolite, on mitogen-activated protein kinase (MAPK) activation in IL-1beta-stimulated rheumatoid synovial fibroblasts. The effects of A77 1726 on the secretion of matrix metalloproteinases (MMPs) from rheumatoid synovial fibroblasts were also examined. A77 1726 partially suppressed IL-1beta-induced ERK1/2 and p38 kinase activation. In contrast, A77 1726 efficiently suppressed IL-1beta-stimulated JNK1/2 kinase activation. Although no suppressive effect was demonstrated on MMP-2, A77 1726 markedly inhibited MMP-1, 3, and 13 secretions from IL-1beta-stimulated rheumatoid synovial fibroblasts. Tissue inhibitor of metalloproteinases-1 (TIMP-1) was constitutively produced from rheumatoid synovial fibroblasts and the suppressive effects of A77 1726 on TIMP-1 production were minimal. Our results suggest that the suppression of the MAPK signalling pathway and MMP synthesis in rheumatoid synovial fibroblasts is a possible mechanism for the inhibitory activity of leflunomide against rheumatoid arthritis. 相似文献
75.
A 39-year-old male was admitted complaining of nonproductive cough and dyspnea on exertion. Death occurred eight months after onset of the symptoms. Autopsy examination showed that the pulmonary trunk and left main pulmonary artery were markedly dilated and completely occluded by a tumor. The tumor had infiltrated into the left upper lobe and mediastinal lymph nodes, and metastatic nodules were found in both lungs and in the left adrenal gland. Small foci of infarction were noted in the lower lobes of both lungs. The tumor cells were of two types; pleomorphic spindle cells and bizarre multinucleated giant cells. Immunohistochemically, they were positive for vimentin, myosin, and lysozyme, but negative for desmin and muscle-specific actin. The cytoplasm of the tumor cells was showed by electron microscopy to contain microfilaments, dense bodies, and pinocytotic vesicles. We diagnosed this case as undifferentiated sarcoma of the pulmonary artery. Approximately 100 cases of pulmonary artery sarcoma have been reported. Histopathologically, almost all of the reported cases showed both spindle cells and pleomorphic giant cells, indicating a biologically anaplastic neoplasm. 相似文献
76.
Yoshiharu Doi Masao Kunioka Akira Tamaki Yoshiyuki Nakamura Kazuo Soga 《Macromolecular chemistry and physics.》1988,189(5):1077-1086
Copolyesters of 3-hydroxybutyric acid (HB) and 3-hydroxyvaleric acid (HV), P(HB-co-HV), were isolated from Alcaligenes eutrophus and characterized by solution NMR, solid-state 13C CP/MAS NMR, and differential scanning calorimetry. The 13C CP/MAS NMR analysis was compatible with that of a random copolyester of oxy-(1-methyl-3-oxotrimethylene) ( B ) and oxy-(1-ethyl-3-oxotrimethylene) ( V ) units which adopts a regular conformation of a 21 -helix in the solid state throughout a wide range of compositions varying from 0 to 90 mol-% V units. The chain dynamics of P(HB-co-HV) in chloroform was studied by analysis of the 13C and 1H NMR spectra. The carbon-13 spin-lattice relaxation times (T1) and nuclear Overhauser enhancements (NOE) indicated that the copolyester molecules in chloroform are not rigid but rather flexible. The conformational preferences of the copolyester molecules were determined by analysis of the 1H NMR spectra. 相似文献
77.
Masataka Takemiya Satoshi Shiraishi Tatsuyuki Teramoto Yoshiharu Miki 《Clinical genetics》1987,31(1):35-44
A 38-year-old Japanese male with Bloom's syndrome (BS) and porokeratosis of Mibelli (PM) developed multiple carcinomas of the skin and lung. There were multiple, spontaneous chromosomal aberrations and frequent sister chromatid exchanges (SCE). Cutaneous delayed-type hypersensitivity reactions were defective and serum IgM was decreased. The lung cancer was treated with radiation, which was effective but caused a severe pulmonary atelectasis and esophageal stricture. The patient expired one-and-a-half years later because of pneumonia. Autopsy disclosed an adenocarcinoma of the colon. The concurrent PM was considered responsible for the occurrence of multiple skin cancers. 相似文献
78.
The polypeptides of adenovirus. V. Young virions, structural intermediate between top components and aged virions 总被引:25,自引:0,他引:25
The turnip yellow mosaic virus (TYMV) RNA-replicase bound to the chloroplast fraction of a participate cell-free preparation isolated from TYMV-infected Chinese cabbage leaves catalyzes the synthesis of RNA of the viral type, “plus” RNA, in the absence of added “minus” RNA template. Addition of TYMV-RNA does not stimulate RNA synthesis. The complex formed by the replicase bound to “minus” RNA template can be removed from the chloroplast fraction by solubilization with a non-ionic detergent, Lubrol W, and separated from insoluble material by centrifugation. The resulting supernatant contains the template-bound replicase as well as a small proportion of template-free replicase molecules. Treatment of this preparation with a polyethylene glycol-dextran two-phase aqueous system at high salt concentration removes the replicase from the template and yields, after centrifugation, a polyethylene glycol upper phase containing the template-free replicase molecules (PEG-enzyme) and a lower dextran phase containing a small proportion of replicase molecules still bound to their template. The soluble PEG-enzyme is markedly stimulated by added RNA. With TYMV-RNA as the added RNA, the product synthesized by the enzyme is RNA complementary to TYMV-RNA, i.e., “minus” RNA, indicating the enzyme uses the viral RNA as template. The “minus”-RNA synthesized remains hydrogen bonded to the viral RNA template and forms a RNase resistant, double-stranded structure. Chromatography on cellulose CF 11 column reveals two different double-stranded structures, one, fully double-stranded, in which the synthesized “minus” RNA strand is hydrogen bonded to template RNA of equal length, and one partly double-stranded and partly single-stranded in which probably the template RNA is very much longer than the synthesized “minus” RNA. The PEG-enzyme seems to be sensitive to high ionic strength since its activity can be completely suppressed by various salts; removal of the salts restores the activity. 相似文献
79.
Morita T Shimada A Ishibashi T Kimura K Haritani M Umemura T 《Journal of comparative pathology》2002,126(2-3):212-215
This report describes a novel spongiform change in the brain stem nuclei of a 9-month-old mixed breed kitten with neurological signs. Histologically, vacuoles were found in perineuronal spaces and neuropil, with mild to moderate astrocytosis in the brain stem nuclei. Vacuoles were not observed in the cytoplasm of neurons and no evidence of neuronal loss was found. Ultrastructurally, there were intramyelinic vacuoles with separation of lamellae at intraperiod lines and larger spaces formed by coalescence of ruptured vacuoles. Immunohistochemically, abnormal accumulation of prion protein (PrP) was not detected in the brain stem lesions. This is, to our knowledge, the first report of a feline spongiform change localized in the brain stem nuclei. 相似文献
80.
During the development of the hippocampus, the action of GABA shifts from depolarizing to hyperpolarizing, and brain-derived neurotrophic factor (BDNF) has important roles in GABAergic transmission. We demonstrate that BDNF (20 ng ml−1 ) rapidly and reversibly potentiates postsynaptic GABAA receptor-mediated currents (by 80.5 ± 14.3 %, n = 10) in hippocampal CA1 pyramidal neurons isolated from postnatal day (P)6 rats, using nystatin-perforated patch-clamp recordings. This potentiation is caused by an elevation of intracellular Ca2+ that occurs in response to the activation of Trk B receptor tyrosine kinase and phospholipase C-γ. The modulation of the GABAA responses by BDNF in hippocampal CA1 pyramidal neurons isolated from P10 rats was more diverse (from potentiating to inhibitory), and at P14, BDNF induced a long-lasting inhibition. In addition, Ca2+ /calmodulin-dependent protein kinase 2 plays important roles in the potentiating, but not in the inhibitory effect, of BDNF on the GABAA responses. These results suggest that changes in the intracellular signalling pathway could contribute to the developmental shift of the actions of BDNF on inhibitory systems. 相似文献