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21.
Nitrate and nitrite reductases in the crude extract of aerobically grown Rhizobium meliloti were determined with methylviologen as electron donor at pH 7. Nitrate reductase was detected in the cells grown in the medium that did not contain nitrate, and in the presence of nitrate the specific activity increased about 2-fold. Nitrite reductase was induced by nitrate and produced ammonia from nitrite. In nitrate reducing cells, two kinds of O2 labile nitrate reductase were found. One enzyme had optimal pH at 7 and was stabilized to O2 by treating with DEAE-Toyopearl 650M. The other had optimal pH at 9 and was stabilized by the addition of dithiothreitol and EDTA. Nitrate reductase stabilized by DEAE-Toyopearl 650M treatment was purified 3,360-fold from crude extract. The purified enzyme showed a single protein band in polyacrylamide gel electrophoresis, and there was no absorption peak in the visible region. It had a molecular weight of 64,000 in SDS PAGE and 58,000 on Sephadex G-100 gel filtration. Km for nitrate was 0.9 mM. It was inhibited by p-chloromercuribenzoate, cyanide, and α,α'-dipyridyl. 相似文献
22.
Statistical detection of HLA and disease association 总被引:1,自引:0,他引:1
Katsuhirci Fukuda Kazuaki Sugawa Akemi Wakisaka Junko Mokiuchi Nobuo Matsuura Yoshiharu Sato 《Tissue antigens》1985,26(2):81-86
23.
Yoshiharu Ohaki Kazuaki Misugi Junya Fukuda Masahiko Okudaira Makoto Hieose 《Pathology international》1987,37(10):1581-1590
Three cases of pancreatoblastoma in children were examined immunohis-tochemically and the results were compared with those of pancreatic duct carcinoma in adults. The pancreatoblastoma demonstrated positive reactions to α-fetoprotein (AFP) (67%: 2/3), α-1-antitrypsin (AAT) (100%: 3/3), carcinoembryonic antigen (CEA) (67% : 2/3) and keratin (33% : 1/3), although CEA was only weakly positive in both cases. On the other hand, adult pancreatic duct carcinoma showed positive reactions as follows; AFP: 3% (1/29), AAT: 21% (6/29), CEA: 97% (28/29) and keratin: 93% (27/29). Also, endocrine substances including insulin, glucagon and somatostatin were all negative in the pancreatoblastomas. Two cases of pancreatoblastoma which were immunohistochemically positive for AFP also showed elevation of the serum AFP level clinically. The different expressive pattern of oncofetal antigens in pancreatoblastoma as compared with pancreatic duct carcinoma in adults may provide further supporting evidence for the embryonic nature of pancreatoblastoma, and suggests that such a pattern might be used as a tumor marker for pancreatoblastoma. ACTA PATHOL. JPN. 37 : 1581-1590, 1987. 相似文献
24.
Kazuo Soga Takeshi Shiono Yoshiharu Doi 《Macromolecular chemistry and physics.》1988,189(7):1531-1541
Three kinds of MgCl2-supported TiCl4 catalysts (ester-free, ethyl benzoate (EB, monoester) and dibutyl phthalate (DNBP, diester) as internal donors) were prepared. Polymerization of propylene was carried out using these catalysts with and without phenyltriethoxysilane (PTES) as an external donor. Significant differences were observed in the kinetic behavior of polymerization among ester-free, monoester, and diester systems. Addition of PTES, however, did not change the kinetic behavior. The polymers produced were separated into three fractions by extraction with boiling heptane and octane, and the molar mass distribution (MMD) curves were measured for these three fractions. The heptane-insoluble, isotactic polymer obtained in the absence of PTES was found to consist of two fractions, octane-soluble and -insoluble. The octane-soluble polymer having lower molar mass contained appreciable amounts of syndiotactic stereoblocks in the chains, whereas the octane-insoluble polymer did not contain such stereoblocks. Addition of PTES drastically increased the octane-insoluble fraction without changing the average molar mass. On the other hand, the MMD curve for the heptane-soluble, atactic polymer gradually shifted to the lower molar mass range with an increase in the concentration of PTES. From these results, the effects of internal and external donors on catalyst activity and stereospecificity were discussed putting emphasis on the differences between monoesters and diesters. 相似文献
25.
TAC-101, a benzoic acid derivative, inhibits liver metastasis of human gastrointestinal cancer and prolongs the life-span 总被引:4,自引:0,他引:4
Koji Murakami Konstanty Wierzba Masaki Sano Jiro Shibata Kazuhiko Yonekura Akihiro Hashimoto Koji Sato Yuji Yamada 《Clinical & experimental metastasis》1998,16(4):323-331
We examined the anti-tumor effect of a novel benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl) benzamide] benzoic acid) on models with liver metastasis. Oral administration of TAC-101 significantly inhibited spontaneous liver metastasis of AZ-521 (human gastric cancer ) by orthotopic implan-tation to athymic nude mice. It also inhibited both the liver metastasis of AZ-521 induced by intrasplenic injection and the secondary lung metastasis from the liver. In addition, TAC-101 inhibited the proliferation of Co-3 (human colon adenocarcinoma) that formed a single nodule in the liver of athymic nude mice by intrahepatic implantation. The growth inhibitory effect of TAC-101 on AZ-521 experimental liver metastasis was observed when treatment was started on day 7, 14, or 21 which may correspond to the progressive stage of liver metastasis in clinical settings. Multiple administration of TAC-101 (8 mg/kg/day) significantly prolonged survival time of the animals with liver met astasis by intrasplenic injection of AZ-521 (T/C = 230%) and A549 (human lung adenocarcinoma; T/C = 186%). These effects of TAC-101 were stronger than those of 5-FU, CDDP or ATRA. Furthermore, TAC-101 inhibited the binding of AP-1 to DNA on electrophoretic mobility shift assay using nuclear extract of AZ-521 cells, although ATRA did not inhibit. These findings suggested that TAC-101 may be a candidate for a new class of anti-cancer agents for liver metastasis. © Rapid Science Ltd. 相似文献
26.
The neuropathologiesl features of the central nervous system in IS autopsy cases of Japanese male with AIDS were reported. Nine patients had various histological changes including a variety of opportunistic infections in six patients (40%), primary malignant lymphoma of the brain in two (13%), AIDS encephalopathy in four (27%) and vacuolar myelopathy in one (7%). Usually, these pathological changes were present concomitantly. AIDS encephalopathy was characterized by infiltration of mono and multinucleated cells and myelin pallor with astrogliosis located predominantly in the cerebral white matter and subcortical gray matter. Furthermore, unevenly distributed neuronal loss of the cerebral cortex was apparent in one case. Diffuse astrocytosis of the gray matter out of proportion to neuronal loss was also an outstanding finding in another case. The present study suggested that not only the white matter changes but also gray matter alterations might be the morphological substrates of AIDS encephalopathy. 相似文献
27.
Yoji Nagashima Nobutaka Arai Yukichi Tanaka Sachiko Yoshida Kaoru Sumino Yoshiharu Ohaki Kazuhiko Matsushita Takashi Morita Kazuaki Misugi 《Virchows Archiv : an international journal of pathology》1991,418(1):77-81
Summary Two cases of renal epithelial tumours are reported in females aged 46 and 66 years respectively. In spite of the large size of the tumours, neither invasive growth nor metastasis was observed. Histologically, the tumours were composed of immature epithelial cells forming tubules with abortive glomeruloid structures. Electron microscopy of tumour cells revealed poorly developed polarity and intracytoplasmic organelles. They showed similar immunohistochemical reactions to those of developing nephrons, particularly to those of the S-shaped body. The nuclear DNA content of the tumour cells was almost euploid. We conclude that the lesions were epithelial tumours of the kidney histologically mimicking developing renal parenchyma. 相似文献
28.
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.
29.
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
30.
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