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31.
The generic names of the brown algaeMyagropsis, Cystoseira andCystophyllum have been used in Japan, Korea and China for a small group of seaweeds whose limits have not been clearly understood. Studies on the development of the eggs and subsequent germlings show that substantial differences occur betweenCystoseira andMyagropsis. Myagropsis Kützing is distinguished fromCystoseira C. Agardh by the following characteristics: (1) the tongue cell is undivided during development of the conceptacle; (2) paraphyses are projected from the conceptacle ostiole and become entangled; (3) during development, oospore germlings are mixed among paraphyses projecting from the ostiole; (4) oospores are large, with eight nuclei at maturity; (5) thirty-two primary rhizoids are produced on the germlings; and (6) the thallus is bilateral in organization. The shape and size of vesicles, their formation, and the presence of cryptostomata have been used as specific characters, but their use cannot be continued. It is concluded that the genusMyagropsis is monotypic, with a single species,M. myagroides (Turner) Fensholt. The status of this species is also discussed.  相似文献   
32.
To elucidate the physiological significance of ketone bodies on insulin and glucagon secretion, the direct effects of beta-hydroxybutyrate (BOHB) and acetoacetate (AcAc) infusion on insulin and glucagon release from perfused rat pancreas were investigated. The BOHB or AcAc was administered at concentrations of 10, 1, or 0.1 mM for 30 min at 4.0 ml/min. High-concentration infusions of BOHB and AcAc (10 mM) produced significant increases in insulin release in the presence of 4.4 mM glucose, but low-concentration infusions of BOHB and AcAc (1 and 0.1 mM) caused no significant changes in insulin secretion from perfused rat pancreas. BOHB (10, 1, and 0.1 mM) and AcAc (10 and 1 mM) infusion significantly inhibited glucagon secretion from perfused rat pancreas. These results suggest that physiological concentrations of ketone bodies have no direct effect on insulin release but have a direct inhibitory effect on glucagon secretion from perfused rat pancreas.  相似文献   
33.
Cos 7 cells transfected with human atrial natriuretic polypeptide (hANP) gene with SV40 enhancer and replication origin sequences expressed hANP gene. The expressed RNA was indistinguishable from native hANP mRNA and the transcribed protein seemed to be properly processed to alpha-hANP and beta-hANP. This system provides a useful approach to investigate the processing of hANPs and the structure-function relationship of amino acid sequences of hANPs.  相似文献   
34.
Using site-directed mutagenesis, Glu-190 or Glu-201 of the beta subunit of the F1-ATPase from the thermophilic bacterium PS3 were replaced with glutamine. It was possible to reconstitute complexes of the mutated beta subunits with alpha and gamma subunits, but the complexes did not have ATPase activity. It is concluded that carboxylic acid side chains of Glu-190 and Glu-201 of the beta subunit are essential for catalytic activity of F1-ATPase.  相似文献   
35.
A human-mouse hybrid segregant HM76Dd40-6 with new characteristics was derived from the hybrid cell line HM76Dd containing human chromosome 19 as the only human chromosome. Three virus sensitivities located on human chromosome 19 (PVS, E11S and RDRC) were lost in HM76Dd40-6, while six other genes (C3, LDLR, EF2, GPI, PEPD and MANB) were retained. Cytogenetic analysis and in situ hybridization using human or mouse repeated sequences as probes showed that the region q13.1-qter of human chromosome 19 had been replaced by a fragment of mouse chromosome. Our results permit further regional assignment for the following five genes on human chromosome 19: GPI in the region cen-q12, MANB in p13.2-q12, E11S and RDRC in q13.1-qter, and EF2 in pter-q12.  相似文献   
36.
T Yoshida  F Cho  N Goto 《Jikken dobutsu》1987,36(3):245-251
The data on hematological and serum biochemical properties of laboratory-bred cynomolgus monkeys (Macaca fascicularis) at different ages were analyzed by discriminant analysis. All the animals had been bred and reared under uniform environmental conditions at Tsukuba Primate Center for Medical Science, N.I.H., Japan. The items used were as follows: red blood cell count (RBC), hematocrit value (Ht), hemoglobin concentration (Hb), mean corpuscular volume (MCV), white blood cell count (WBC), glutamic oxaloacetic transaminase activity (GOT), glutamic pyruvic transaminase activity (GPT), total protein concentration (TP), albumin concentration (ALB), albumin-globulin ratio (A/G), blood urea nitrogen (BUN), glucose concentration (GLU), total cholesterol concentration (TCHO), free cholesterol concentration (FCHO), triglyceride concentration (TG) and alkaline phosphatase activity (ALP). In total, 1086 animals in 10 age groups were examined. Data analyses were done with respect to the difference of sex. Discrimination was possible by Mahalanobis' generalized distance between centroids of groups. In canonical discriminant analysis (discriminant analysis with reduction of dimensionality), age was highly correlated to the value of the first canonical variate. From the approximate relative value of the eigenvector of the first canonical variate, the most discriminant variables are WBC, TP, ALB, A/G, TCHO, FCHO, TG, and ALP. It can be concluded that periodic measurement of these 8 parameters is necessary and sufficient to monitor the physiological conditions of growing monkeys.  相似文献   
37.
Serum total thyroxine (T4), total triiodothyronine (T3), T4-binding globulin (TBG), free T4(FT4) and free T3(FT3) concentrations and the T3-uptake(T3-U) value were estimated in 11 patients with subacute thyroiditis, and compared with the same parameters in 11 patients with Graves' disease, whose serum T4 concentrations were similar to the former group. Seven patients with subacute thyroiditis, who were treated with dicrofenac sodium alone, were investigated as to the sequential changes in serum parameters during their clinical courses. The mean serum T3-U value and FT4, T3 and FT3 concentrations in patients with subacute thyroiditis were increased, but all were significantly lower than those in patients with Graves' disease (p less than 0.01, p less than 0.001, p less than 0.001 and p less than 0.001, respectively). Three patients with subacute thyroiditis, who showed shorter duration of symptoms than 10 days, had serum TBG excess. Thus the mean (+/- SD) serum TBG concentration (26.5 +/- 8.4 micrograms/ml) was significantly higher than that (18.3 +/- 2.9 micrograms/ml) in patients with Graves' disease (p less than 0.02). The ratios of serum T3 to T4 and FT3 to FT4 in patients with subacute thyroiditis were also significantly lower than those in patients with Graves' disease (p less than 0.001 and p less than 0.001, respectively). The serum FT4 in 7 patients treated with dicrofenac sodium alone decreased to the normal range after 3 to 8 weeks from the onset of the illness. In 3 patients with TBG excess and one patient (TBG; 29.0 micrograms/ml), serum TBG declined in consequence of the serum FT4 normalization.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
Azopigments were obtained from the delta fraction of bilirubin (mammalian biliprotein) in cholestatic sera of men, rats and guinea pigs by diazo reaction with diazotized p-iodoaniline and analysed by t.l.c. Delta bilirubin of men and rats generated both unconjugated and glucuronide-conjugated azodipyrroles, whereas that of guinea pigs, in which the predominant form of conjugated bilirubin in serum was bilirubin monoglucuronide, generated only unconjugated azodipyrrole. We further analysed the azopigments by reversed-phase h.p.l.c. to distinguish their endovinyl and exovinyl isomers. The results indicated (a) that covalent binding of bilirubin to protein occurs exclusively on the conjugated dipyrrolic (either endovinyl or exovinyl) half of the parent conjugated bilirubin, (b) that both bilirubin monoglucuronide and bilirubin diglucuronide generate delta bilirubin, the latter yielding a 'conjugated' form of delta bilirubin that preserves the glucuronic acid moiety on the dipyrrolic half not bound covalently to protein, and (c) that therefore at least four forms of delta bilirubin exist in jaundiced sera of men and rats.  相似文献   
39.
Dermatan sulfate proteoglycan chains were detected in tissue sections treated with chondroitin B-lyase (0.01 units/ml) in 20 mM Tris-HCl (pH 8.0) for 1 hr, followed by staining with antibody 9A2 specific for unsaturated uronic acid coupled to N-acetylgalactosamine-4 sulfate. In contrast, after treatment with chondroitin B-lyase, no positive staining was observed with antibodies 3B3 and 1B5 which react to the unsaturated uronic acid coupled to N-acetylgalactosamine 6-sulfate and unsaturated uronic acid coupled to N-acetylgalactosamine, respectively. The distribution of dermatan sulfate thus revealed was confirmed by comparison with that found by monoclonal antibody 6B6 which reacts with small proteoglycans carrying dermatan sulfate side chains. The localization of positive staining in fibrous connective tissues was almost identical with these two procedures.  相似文献   
40.
H Kanno  I Y Huang  Y W Kan  A Yoshida 《Cell》1989,58(3):595-606
Structural analysis revealed the existence of two types of subunits in human red cell glucose-6-phosphate dehydrogenase. The two subunits have the same COOH region consisting of 479 amino acid residues, but their NH2-terminal regions are different in size and sequence. The minor subunit can be fully encoded by the X-linked G6PD cDNA, but the NH2-terminal region of the major subunit cannot. The cDNA and the gene for the NH2-terminal region of the major subunit were cloned and characterized. Southern blot hybridization indicated that the gene for the NH2-terminal region is on chromosome 6, not on the X chromosome. Northern blot hybridization demonstrated an existence of two separate mRNA components, one for the COOH-terminal region and the other for the NH2-terminal region. Two separate structural genes, the X-linked and chromosome 6-linked genes, must be coresponsible for encoding the single chain subunit. Either cross-translation of two mRNAs, or transpeptidation, or some other mechanism must be involved in the synthesis of human red cell G6PD.  相似文献   
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