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排序方式: 共有1305条查询结果,搜索用时 78 毫秒
1.
Melanin concentrating hormone. III. Melanin concentrating hormone (MCH): the message sequence 总被引:1,自引:0,他引:1
Melanin concentrating hormone (MCH) is a heptadecapeptide synthesized by the hypothalamus and secreted by the neurohypophysis of the teleost pituitary gland. MCH stimulates melanosome aggregation within teleost melanocytes but also exhibits MSH-like (melanosome dispersing) activity on tetrapod (frog and lizard) melanocytes. We have synthesized a number of MCH analogues to determine the essential features of the primary structure necessary to stimulate either melanosome aggregation or dispersion in fish or tetrapod melanocytes, respectively. An analysis of the potencies and actions of these analogues on vertebrate melanocytes is provided and demonstrates that the two activities have different structural requirements. 相似文献
2.
In addition to the known triterpene motiol, hopenol-b (hop-22(29)-en-3β-ol) was isolated from the whole herb of Euphorbia supina. It has not been found previously in nature, though it has been prepared by both synthetic and biosynthetic methods. 相似文献
3.
S Yasugi T Matsunaga T Mizuno 《Comparative biochemistry and physiology. A, Comparative physiology》1988,91(3):565-569
1. Stomachs of adult teleosts and elasmobranchs reacted to an anti-embryonic chicken pepsinogen antiserum (anti-ECPg) as well as to an anti-adult chicken pepsinogen antiserum (anti-ACPg). 2. Zymograms and immunoblots of stomach extracts revealed that anti-ECPg- and anti-ACPg-reactive substances possess peptic activity. 3. The possible relationship between anti-ECPg-reactive pepsinogens in fish and prochymosins in higher vertebrates is discussed. 相似文献
4.
Ryuji Kawaguchi J. Grant Burgess Toshifumi Sakaguchi Haruko Takeyama Richard H Thornhill Tadashi Matsunaga 《FEMS microbiology letters》1995,126(3):277-282
Abstract Most of the 16S ribosomal RNA gene of a sulfate-reducing magnetic bacterium, RS-1, was sequenced, and phylogenetic analysis was carried out. The results suggest that RS-1 is a member of the δ-Proteobacteria, and it appears to represent a new genus. RS-1 is the first bacterium reported outside the α-Proteobacteria that contains magnetite inclusions. RS-1 therefore disrupts the correlation between the α-Proteobacteria and possession of magnetite inclusions, and that between the δ-Proteobacteria and possession of greigite inclusions. The existence of RS-1 also suggests that intracellular magnetite biomineralization is of multiple evolutionary origins. 相似文献
5.
Yoshifumi Abe Atsuhiko Matsunaga Ryota Matsuzawa Toshiki Kutsuna Shuhei Yamamoto Kei Yoneki Manae Harada Ryoma Ishikawa Takaaki Watanabe Atsushi Yoshida 《PloS one》2016,11(3)
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients. 相似文献
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Summary Chromosome variants were evaluated on the basis of their DNA-replication pattern (LBA). The size of late-replicating centromeric heterochromatin of chromosomes 2, 5, 6, 7, 8, 10, 11, 12, 17, 18, 19, and 20, i.e., pairs without Q or C (qh) variants, was measured by means of a microdensitometer. The results were expressed in area, related to that of a euchromatic segment of a given chromosome, and were assigned into five classes based on the difference in standard deviation from an average relative size. LBA variants in each of 12 pairs were found in 29%–42% of the chromosomes. 相似文献
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9.
Tadashi Matsunaga Haruko Takeyama Yuki Miura Takeshi Yamazaki hiroyuki Furuya Koji Sode 《FEMS microbiology letters》1995,133(1-2):137-141
Abstract Screening of fatty acid composition in 150 strains of marine microalgae, cyanobacteria and green algae was carried out, and 20 strains showed relatively high contents of palmitoleic acid. Among them, two cyanobacteria, Phormidium sp. NKBG 041105 and Oscillatoria sp. NKBG 091600, showed an unusually high cis -palmitoleic acid content (54.5% and 54.4% of total fatty acid, respectively). Phormidium sp. NKBG 041105 had the highest cis -palmitoleic acid content per biomass (46.3 mg (g dry cell weight)−1 ), and cis -palrnitoleic acid composition was found to be constant with varying temperature. These results indicate that this cyanobacterium could be considered as a new source for palmitoleic acid. 相似文献
10.
Haruko Takeyama J. Grant Burgess Hiroaki Sudo Koji Sode Tadashi Matsunaga 《FEMS microbiology letters》1991,90(1):95-98
Listeria monocytogenes possessed glucose oxidase and NADH oxidase activities in whole cells and lysed protoplasts respectively. The NADH oxidase activity sedimented with the membrane fraction and was inhibited by the respiratory inhibitors rotenone, 2-heptyl-4-hydroxy-quinoline-N-oxide and cyanide, suggesting the presence of a membrane associated respiratory chain. 相似文献