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1.
Toshiro Akino Nobuyuki Nakamura Koki Horikoshi 《Applied microbiology and biotechnology》1987,26(4):323-327
Summary An alkalophilic bacterium producing high amounts of the cell-associated -mannosidase and extracellular -mannanase was isolated from soil. The isolate (AM-001) that grew well in alkaline pH media was identified as a strain of Bacillus sp. The optimal cultivation temperature for enzyme production was 31° C for -mannosidase and 37° C for -mannanase with the optimum production medium composed of 1% konjac powder, 0.2% yeast extract, 2% Polypepton, 0.1% K2HPO4, 0.02% MgSO4 · 7H2O and 0.5% Na2CO3. Optimum pH and temperature for -mannosidase were 7.0 and 55° C, and for -mannanase were 9.0 and 65° C. 相似文献
2.
T Inoue N Watanabe S Saito M Yamasaki H Saito N Shirakawa 《Endocrinologia japonica》1986,33(6):919-927
A highly sensitive and specific RIA for IGF-I has been developed using recombinant DNA-derived IGF-I of very high purity and specific antiserum to it. This assay system could detect IGF-I at as low concentrations as 20-30 ng/ml. The intra-assay and interassay coefficients of variation at various concentrations of IGF-I were 4.9 to 6.5% and 5.4 to 8.0%, respectively. The recovery rate of pure IGF-I added to plasma was 77.0 +/- 3.7%. The antiserum did not cross-react with porcine insulin, biosynthetic human insulin, hGH, hEGF, the synthetic C-domain of IGF-I or that of IGF-II, but reacted equally with an analog, Thr59-IGF-I. Plasma IGF-I was extracted by the acid-ethanol method before assay to separate IGF-I from its binding protein. When plasma IGF-I was assayed without extraction, the inhibition curves of serial dilution of plasma samples from several individuals were not parallel to the standard curve of IGF-I. The plasma concentration of IGF-I was 147 +/- 49 ng/ml (mean +/- SD) in 156 normal adults aged from 20-59 years. As reported by others, the IGF-I levels were low in cord plasma (41.8 +/- 23.5 ng/ml) and plasma of patients with GH deficiency (64.6 +/- 42.0 ng/ml), while its levels were high in normal children of pubertal ages (12-13 yr, 365 +/- 126 ng/ml) and in patients with active acromegaly (562 +/- 115 ng/ml). This RIA system is a simple and useful method for determining plasma IGF-I in normal and diseased states. 相似文献
3.
The glycoprotein nature of solubilized muscarinic acetylcholine receptors from bovine cerebral cortex 总被引:4,自引:0,他引:4
O Shirakawa T Kuno C Tanaka 《Biochemical and biophysical research communications》1983,115(3):814-819
Muscarinic acetylcholine receptors were solubilized from bovine cerebral cortex with 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate. The so-obtained receptors could be precipitated by Wheat Germ (73%), Concanavalin A (55%), Lens Culinaris (36%) and Ricinus Communis (26%), but not by Peanut, Dolichus Biflorus and Ulex Europaeus. On Wheat Germ- and Concanavalin A-affinity chromatography, the solubilized muscarinic receptors were retained on both columns and subsequently eluted with N-acetylglucosamine and alpha-methyl-D-mannoside, respectively. A high concentration (100 micrograms/ml) of Wheat Germ or Concanavalin A did not interfere with Z-[3H]quinuclidinyl benzilate binding, thereby suggesting that the lectin binding sites are not directly involved in the receptor binding function. These solubilized muscarinic receptors are postulated to contain carbohydrate residues, N-acetyl-glucosamine, mannose and galactose, as glycoprotein. 相似文献
4.
We have studied ouabain-resistant, external sodium-stimulated, lithium efflux (LiNa countertransport) in red blood cells from 21 borderline hypertensives with at least one hypertensive first degree relative (BH-F), 19 borderline hypertensives without family history of essential hypertension (BH-NF), and 35 age-matched normotensive subjects. The data indicate the finding of an increased LiNa countertransport in all BH (F+NF), but with a significant overlap between BH values and control ones: LiNa countertransport is significantly higher only in BH-F but it is normal in BH-NF. Moreover, there is a significant correlation of LiNa countertransport to total peripheral resistance but not to mean blood pressure in all hypertensive patients. It is suggested that in BH the increase of erythrocyte Na flux is mediated by the NaNa exchange diffusion, and its abnormality may be associated to the hereditary trait of essential hypertension rather than the high blood pressure per se, probably resulting in the development of hypertension, through the increased vascular smooth muscle tone. 相似文献
5.
Nakao T Narita S Tanaka K Hara H Shirakawa J Noshiro H Saga N Tsunoda N Kawata K 《Theriogenology》1983,20(1):111-119
The effect of an intramuscular injection of a new analog of gonadotropin-releasing hormone (GnRH), fertirelin, on the first-service pregnancy rate in cows was investigated by a double blind experiment. A total of 1,194 cows was injected intramuscularly either with 100 mug of GnRH or placebo (physiological saline solution) at the time of first insemination postpartum. Pregnancy rate (number of cows calved/ number of cows serviced) was 57.2 % in 605 cows treated with GnRH, while the performance was 49.7 % in 589 cows of the placebo group. The difference of pregnancy rates in both groups was significant (P<0.05). GnRH injected at insemination was effective, especially in cows at the first and third lactations, cows at 101 days postpartum or later, cows with daily milk yield of 26-30 kg, and also in cows from the area where a regional average fertility was relatively low. 相似文献
6.
Toshiro Nagayoshi Marie-Genevive Mattei Edith Passage Robert Knowlton Mon-Li Chu Jouni Uitto 《Genomics》1989,5(4):932-935
Laminin, an integral component of basement membranes, consists of three subunit polypeptides, A, B1, and B2 chains. We have recently isolated cDNAs corresponding to human laminin A chain. These cDNAs were utilized for chromosomal in situ hybridizations to establish the genomic location of the laminin A chain gene. Metaphase chromosomes of PHA-stimulated human peripheral blood leukocytes were examined by in situ hybridization with 3H-labeled cDNAs, and the chromosomes were identified by R-banding (fluorochrome-photolysis-Giemsa method). The results indicated that the human laminin A chain is at locus 18p11.3. Since human laminin B1 and B2 chain genes have been previously mapped to chromosomes 7 and 1, respectively, the results indicate that genes encoding human laminin chains reside in separate chromosomes. 相似文献
7.
8.
Hohzoh Kiyohara Toshiro Watanabe Junko Imai Noboru Takizawa Takashi Hatta Kazutaka Nagao Akira Yamamoto 《Applied microbiology and biotechnology》1990,33(6):671-676
Summary To breed industrially useful strains of a slow-growing, red-pigment-producing strain ofMonascus anka, protoplasts ofM. anka MAK1 (arg) andAspergillus oryzae AOK1 (met, thr) were fused. A mixture of protoplasts prepared from mycelia ofM. anka MAK1 treated with 2% Usukizyme and ofA. oryzae AOK1 treated with 2% Usukizyme and 0.2% NovoZym 234 was incubated with 30% (w/v) polyethylene glycol no. 6000. Heterokaryon fusants complementing the auxotrophies of both mutants were isolated on minimal medium, but segregated into red (MAK1) and white (AOK1) sectors after being cultured on a complete medium. After irradiation with UV light, the fusants gave stable heterozygous diploids that formed long white hyphae. These diploids, which had twice as much DNA in the nucleus as their parents, grew more rapidly than the parent strain YZT1, and produced ethanol earlier than the parents. Production of amylase, protease, and kojic acid by the fusants was intermediate in amount between that of the two parents. 相似文献
9.
10.
Tomokazu Indoh Sachiko Shirakawa Tohru Kubota Teruo Yashiki Emiko Isogai Nobuhiro Fujii 《Microbiology and immunology》1996,40(9):675-679
Persistent infections with mumps virus were established in several human lymphoid cells of T-cell origin (Molt-4, TALL-1, and CCRF-CEM) and human monocyte cells (U937 and THP-1). 2′,5′-Oligoadenylate synthetase (2–5AS) activity was demonstrated to be only slightly induced by interferon (IFN) or TPA (12-O-tetradecanoyl-phorbol-13-acetate) treatment in these cells. Treatment of the persistently infected cells with IFN or TPA did not stimulate an increase in the amount of synthetase mRNA. Induction of cell differentiation and augmentation of IFN production by TPA were demonstrated in U937 cells persistently infected with mumps virus (U937-MP). Similar results for IFN production were obtained from differentiated U937 cells. It is suggested that cell differentiation of U937 cells might be associated with the development of IFN inducibility. 相似文献