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301.
Evidence from cDNA cloning has shown that calcitonin receptors (CTRs) have seven potential transmembrane domains. In this study, structural analysis of CTRs from ten cultured human tumor cell lines and 117 human blood samples demonstrated allelic variants at the 1377th nucleotide in intracellular domain 4, expressing either proline or leucine as the 463rd amino acid. It was found that the variant with proline at this site was the more prevalent type of CTR among the Japanese population. Received: 21 June 1996  相似文献   
302.
A method for distinguishing between membrane and soluble proteins in an amino acid sequence was developed, using only two parameters associated with the hydrophobicity: the average hydrophobicity and the power spectral density of period longer than 30 residues. The power spectral density was calculated by a maximum entropy method of Fourier transformation. Membrane proteins could be distinguished from soluble proteins with a distinction rate as high as 97%. This fact strongly suggests that the morphology of proteins, i.e., membrane or soluble forms, is determined thermodynamically through the hydrophobicity of polypeptides.  相似文献   
303.
We present here the second complete genome of anaerobic ammonium oxidation (anammox) bacterium, Candidatus (Ca.) Brocadia pituitae, along with those of a nitrite oxidizer and two incomplete denitrifiers from the anammox bacterial community (ABC) metagenome. Although NO2 reduction to NO is considered to be the first step in anammox, Ca. B. pituitae lacks nitrite reductase genes (nirK and nirS) responsible for this reaction. Comparative genomics of Ca. B. pituitae with Ca. Kuenenia stuttgartiensis and six other anammox bacteria with nearly complete genomes revealed that their core genome structure contains 1,152 syntenic orthologues. But nitrite reductase genes were absent from the core, whereas two other Brocadia species possess nirK and these genes were horizontally acquired from multiple lineages. In contrast, at least five paralogous hydroxylamine oxidoreductase genes containing candidate ones (hao2 and hao3) encoding another nitrite reductase were observed in the core. Indeed, these two genes were also significantly expressed in Ca. B. pituitae as in other anammox bacteria. Because many nirS and nirK genes have been detected in the ABC metagenome, Ca. B. pituitae presumably utilises not only NO supplied by the ABC members but also NO and/or NH2OH by self-production for anammox metabolism.  相似文献   
304.
The effect of leuprolide acetate (D-Leu6-[des-Gly10-NH2]-LH-RH ethylamide acetate) for depot suspension (TAP-144-SR), a synthetic analog of luteinizing hormone-releasing hormone, was examined in three doses in 36 patients (34 girls, 2 boys) with central precocious puberty. TAP-144-SR was injected subcutaneously every four weeks for twelve weeks, and clinical symptoms and plasma and urinary levels of various hormones were followed every four weeks. Eleven girls given 10 micrograms/kg showed a significant decrease in peak plasma LH and FSH responses to LH-RH test, but basal plasma LH and FSH did not change significantly. In 13 patients (11 girls and 2 boys) given 30 micrograms/kg and 12 girls given 90 micrograms/kg, both basal and peak LH and FSH were significantly suppressed. Urinary excretion of LH decreased significantly in all groups except in the 10 micrograms/kg group. Urinary excretion of FSH did not change significantly in the 10 and 30 micrograms/kg groups, but it decreased significantly in the 90 micrograms/kg group. In girls, plasma and urinary estradiol also fell greatly, but the difference was insignificant except in the 90 micrograms/kg group. Regression of sexual characteristics was observed in almost half of the patients at the 12th week of the treatment. Side effects were minimal. A dose of more than 30 micrograms/kg of TAP-144-SR is effective in suppressing gonadotropins and causing improvement of clinical symptoms, and appears to be useful in treating children with central precocious puberty.  相似文献   
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