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981.
982.
A case of Cushing's syndrome due to huge adrenocortial multinodular hyperplasia who was shown to be hyperresponsive to ACTH administration, unresponsive to metyrapone administration and resistant to dexamethasone high dose suppression was reported. After two years' duration of his symptoms, the multinodular adrenals weighing 161 g in total were removed by bilateral adrenalectomy which abolished his symptoms. Postoperatively, plasma ACTH rose gradually to above normal levels, suggesting the presence of primary disorder in the hypothalamus-pituitary axis. 相似文献
983.
The present study was performed to examine the effect of angiotensin II on hepatic angiotensinogen production in adrenalectomized rats. The hepatic angiotensinogen mRNA levels in rats without adrenal glands increased 2.8-fold 4 h after the start of angiotensin II infusion. In intact rats with adrenal glands, the hepatic angiotensinogen mRNA levels increased 2.7-fold 4 h after the start. The angiotensin II infusions did not only increase angiotensinogen mRNA levels in intact rats but also increased those in adrenalectomized rats. The results suggest that the angiotensinogen response to ANG II was not dependent on adrenal glucocorticoid. 相似文献
984.
Molecular cloning and gibberellin-induced expression of multiple cysteine proteinases of rice seeds (oryzains) 总被引:9,自引:0,他引:9
H Watanabe K Abe Y Emori H Hosoyama S Arai 《The Journal of biological chemistry》1991,266(25):16897-16902
We screened a cDNA library of germinating rice seeds with a cDNA for aleurain (cysteine proteinase from barley) and obtained three distinct types of cDNA clones encoding three species of cysteine proteinases (oryzains alpha, beta, and gamma). The deduced amino acid sequences are distinct in part, but, on the whole, are similar to one another. The three sequences all contain the catalytic triad Cys25-His159-Asn175 (papain numbering). The three oryzains are similar to one another and also to other known cysteine proteinases such as papain and cathepsin H with respect to the sequences around the active site residues and the COOH-terminal Trp-rich region. Amino acid sequence comparison revealed that oryzains alpha and beta are similar not only to each other (70% similarity) but also to actinidin and papain (about 50%), whereas oryzain gamma was rather similar to aleurain (85%) and cathepsin H (60%). Northern blot analysis revealed that the mRNAs for the three oryzains are expressed only in seeds, not in shoots or roots, and show different expression profiles during germination and when the seeds are treated with gibberellic acid. Oryzains alpha and gamma are expressed continuously during germination with a maximum expression 5 days from the start of germination, but are present in neither ripening nor ripened seeds. On the other hand, oryzain beta is expressed not only during germination, but also in ripened seeds before germination. It was noted that the expression of the three oryzain mRNAs is enhanced in different manners by gibberellic acid but is not enhanced by other plant hormones such as auxin. The induction of oryzain beta mRNA is transient, reaching a maximum in 4 h from the addition of giberellic acid and diminishing rapidly thereafter, while the induction of oryzain alpha and gamma mRNAs continues over 5 days. Thus, multiple systems involving cysteine proteinases must be differentially involved in the germination process, probably under hormonal control. 相似文献
985.
Tapan Kumar Mazumder Naomichi Nishio Satoshi Fukuzaki Shiro Nagai 《Applied microbiology and biotechnology》1987,26(6):511-516
Summary Production of vitamin B-12 compounds from methanol was carried out by Methanosarcina barkeri Fusaro, an anaerobic methanogen. The methanogen released about 40% to 70% of corrinoids irrespective of the culture medium
used. The use of cysteine instead of Na2S as the sole sulphur source for cell growth led to an increase in the cobalt chloride concentration in the culture medium
up to 16 times the normal (0.6 mg·l-1) without medium precipitation. This in turn resulted in an intracellular vitamin B-12 content of 5.6 mg·g dry cell-1, the rest being discharged into the culture supernatant; this was 87 mg·l-1, 73% of the total corrinoids after 20 repeated intermittently fed cultures and the final cell concentration was 5.8 g dry
cell·l-1. Taking advantage of this, continuous production of extracellular vitamin B-12 compounds was attempted with a fixed-bed bioreactor
(carrier: diatomaceous clay). At a steady state operation at space velocity of 9 to 11 day-1, the concentration of the discharged corrinoid was 6.8 to 7.9 mg·l-1, having a vitamin B-12 activity of about 4 mg·l-1. Total cell mass retained in the reactor was 39.6 g dry cell l-reactor-1. Identification of the corrinoids revealed that 19% of the total corrinoids was comprised of the vitamin B-12 Factor III
(5-hydroxybenzimidazolyl cobamide) and the remainder were mainly the base-free vitamin B-12 Factor B (cobinamide and its derivatives). 相似文献
986.
Abstract Monoclonal antibodies of subclasses IgG1 and IgG2b and specific for the O4 antigen of Escherichia coli 20025 (O4 : K12 : H− ) and the capsular K12 polysaccharide of the same strain (IgM) were obtained with the hybridoma technique using spleen cells from Balb/c mice, immunized with a crude bacterial extract, and Sp2/O-Ag8 myeloma cells. The anti-O4 antibodies reacted exclusively with the O4 lipopolysaccharide and not with those from serologically O-cross reactive E. coli . The anti-K12 antibodies recognized as epitope (part of) the KDO moiety of the capsular K12 polysaccharide. Not only anti-K12, but also anti-O4 antibodies effectively phagoopsonized encapsulated E. coli 20025. The opsonized bacteria were killed in subsequent in vitro phagocytosis by human leokocytes in the presence of human serum complement. 相似文献
987.
Abe Widra 《Mycopathologia》1959,11(3):177-184
Summary Nuclear division inCandida albicans during budding and blastospore formation is described. Classic mitotic division as it occurs in the higher ascomycetes is not seen. Instead, the semi-lunar (crescentic) chromatinic material in the nucleus increases so as to fill the nuclear vesicle, often assuming a toroid-like aspect. The nucleus then divides into two crescentic masses one of which migrates to the daughter cell. No external centriole or spindle apparatus could be observed. No chromosomes could be resolved. Nuclear division in the mold phase duplicated that found in the yeast phase. Colchicine treatment of yeast phase cells resulted in the appearance of large polynucleate and polyploid cells in one strain ofC. albicans.Supported by U.S.P.H.S. Grant E-1700. 相似文献
988.
989.