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排序方式: 共有1595条查询结果,搜索用时 15 毫秒
1.
Yusuke Nakamura Michio Ogawa Takahiro Nishide Mitsuru Emi Goro Kosaki Seiichi Himeno Kenichi Matsubara 《Gene》1984,28(2):263-270
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase. 相似文献
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Masaki Fujimura Yasushi Miyake Kohhei Uotani Kazunori Kanamori Tamotsu Matsuda 《Prostaglandins & other lipid mediators》1988,35(3)
Effect of a thromboxane synthetase inhibitor (OKY-046) on bronchoconstriction induced by aerosol leukotriene C4 and histamine was studied in anesthetized, artificially ventilated guinea pigs in order to examine whether secondary release of thromboxane A2 is produced by aerosol leukotriene C4 or not. 0.01–1.0μg/ml of leukotriene C4 and 12.5–400μg/ml of histamine inhaled from ultrasonic nebulizer developed for small animals caused dose-dependent increase of pressure at airway opening (Pao) which is considered to be an index representing bronchial response. Pretreatment of the animals with intravenous OKY-046 (100mg/kg) significantly reduced the airway responses produced by inhalation of 0.1, 0.33 and 1.0μg/ml of leukotriene C4, while the pretreatment did not affect the histamine dose-response curve. Based on these findings and previous reports (6, 7), it is suggested that aerosol leukotriene C4 activates arachidonate cyclooxygenase pathway including thromboxane A2 synthesis and the released cyclooxygenase products have bronchodilating effect as a whole 相似文献
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Structure of the Bombyx mori fibroin light-chain-encoding gene: upstream sequence elements common to the light and heavy chain. 总被引:21,自引:0,他引:21
Yoshimi Kikuchi Kazuyuki Mori Satoshi Suzuki Kazunori Yamaguchi Shigeki Mizuno 《Gene》1992,110(2):151-158
Two overlapping genomic clones containing the fibroin light-chain (Fib-L)-encoding gene (Fib-L) were obtained from the cosmid library of the silkworm, Bombyx mori J-139, by hybridization with the Fib-L cDNA clone. Sequencing of the 14.6-kb region revealed that Fib-L was 13472 bp long containing seven exons, and that the gene contained a large first intron which occupied about 60% of the gene. Comparison of restriction patterns of the J-139 Fib-L with those of eight other B. mori breeds producing normal-level fibroin demonstrated that considerable restriction-fragment length polymorphisms were present in regions containing the first intron and the 3′-flanking sequence. However, sizes of the Fib-L mRNA and the Fib-L polypeptide were very similar among the nine breeds tested, suggesting that the exon sequences and the splice signals were all well conserved. 5′-Flanking regions of Fib-L and the fibroin heavy-chain (Fib-H)-encoding gene (Fib-H) compared in this study contained three 18-30-bp sequences of high similarity and many 8-10-bp common elements, six of which coincided with the binding sites of homeodomain proteins. Gel retardation assays with the nuclear extracts of the posterior and middle silk glands suggested that protein factors present in the posterior silk-gland nuclei could bind to a set of those common upstream elements. 相似文献
6.
A leptomycin B resistance gene of Schizosaccharomyces pombe encodes a protein similar to the mammalian P-glycoproteins 总被引:4,自引:0,他引:4
Kazunori Nishi Minoru Yoshida Marie Nishimura Mitsuo Nishikawa Makoto Nishiyama Sueharu Horinouchi Teruhiko Beppu 《Molecular microbiology》1992,6(6):761-769
Screening for leptomycin B (LMB)-resistant transformants in a gene library constructed in Schizosaccharomyces pombe with the chromosomal DNA of an LMB-resistant mutant of S. pombe and with multicopy plasmid pDB248' as the vector led to the isolation of a gene, named pmd1+, encoding a 1362-amino-acid protein. This protein showed great similarity in amino acid sequence to the mammalian P-glycoprotein encoded by the multidrug resistance gene, mdr, and the Saccharomyces cerevisiae a-factor transporter encoded by STE6. In addition, computer analyses predicted that the protein encoded by pmd1+ formed an intramolecular duplicated structure and each of the halves contained six transmembrane regions as well as two ATP-binding domains, as observed with the P-glycoproteins and the STE6 product. Consistent with this was that S. pombe cells containing the pmd1+ gene on a multicopy plasmid showed resistance not only to LMB but also to several cytotoxic agents. The pmd1 null mutants derived by gene disruption were viable and hypersensitive to these agents. All these data suggest that the pmd1+ gene encodes a protein that is a structural and functional counterpart of mammalian mdr proteins. 相似文献
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Enrichment and characterization of clonogenic epithelial cells from adult rat liver and initiation of epithelial cell strains 总被引:8,自引:0,他引:8
Kazunori Furukawa Tomiko Shimada Patricia England Yohichi Mochizuki Gary M. Williams 《In vitro cellular & developmental biology. Plant》1987,23(5):339-348
Summary A highly efficient method is described for obtaining prolifertive epithelial cells from adult rat livers for the reproducible
establishment of liver epithelial cell strains. When cells were isolated from livers of 10-to 15-wk-old male Fischer 344 rats
by a collagenase-perfusion method, collected by centrifugation at 50×g for 5 min, and cultured in Williams' medium E containing fetal bovine serum and dexamethasone, colonies of epithelial cells
different in size and morphology from hepatocytes were obtained. Sequential perfusion with collagenase and dispase yielded
numerous epithelial cell colonies. When isolated cells were fractionated by differential centrifugation, the great majority
of hepatocytes were sedimented at 50 ×g for 1 min, whereas many non-hepatocytic cells remiined in the supernatant and could be sedimented by a second centrifugation
at 50×g for 5 min. Culture of the two fractions revealed that almost all the epithelial cell colonies were derived from cells in
the non-hepatocytic cell fraction. The epithelial cells were cytochemically negative for γ-glutamyl transpeptidase activity,
whereas an increase in the activity was detected in hepatocytes with duration in culture. Ultrastructural characteristics
of hepatocytes were not found in the cells of newly established cell strains. These results suggest that adult rat liver epithelial
cells propagable in culture were derived from a cell type other than the hepatocyte. 相似文献
9.
Inhibition of lipid transfer by a unique high density lipoprotein subclass containing an inhibitor protein 总被引:2,自引:0,他引:2
We have isolated from human plasma a unique subclass of the high density lipoproteins (HDL) which contains a potent lipid transfer inhibitor protein (LTIP) that inhibited cholesteryl ester, triglyceride, and phospholipid transfer mediated by the lipid transfer protein, LTP-I, and phospholipid transfer mediated by the phospholipid transfer protein, LTP-II. This HDL subclass not only inhibited cholesteryl ester transfer from HDL to LDL or VLDL, but also inhibited cholesteryl ester transfer from HDL to HDL. The inhibitor protein was isolated by sequential chromatography of human whole plasma on dextran sulfate-cellulose, phenyl-Sepharose, and chromatofocusing chromatography. Isolated LTIP had the following characteristics: an apparent molecular weight of 29,000 +/- 1,000, (n = 10) by sodium dodecyl sulfate gel electrophoresis, and an isoelectric point of 4.6 as determined by chromatofocusing. LTIP remained functional following delipidation with organic solvents. Antibody to LTIP was produced, and an immunoaffinity column of the anti-LTIP was prepared. Passage of human, rat, or pig whole plasma over the anti-LTIP column enhanced cholesteryl ester transfer activity in human (17%), pig (200%), and rat plasma (125%). The HDL subclass containing LTIP was isolated from whole human HDL (d 1.063-1.21 g/ml) by immunoaffinity chromatography. The isolated LTIP-HDL complex was shown to: i) contain about 60% protein and 40% lipid, ii) have alpha and pre-beta electrophoretic mobility, iii) have particle size distribution somewhat smaller than whole HDL, about 100,000 daltons, as determined by gradient gel electrophoresis, and iv) contain only a small amount of apoA-I (less than 5%) and a trace amount of apoA-II. Assay of ultracentrifugally obtained lipoprotein fractions revealed that approximately 85% of the total functional LTIP activity was in the d 1.063-1.21 g/ml HDL fraction. Furthermore, immunoblot analysis of whole plasma by nondenaturing gradient gel electrophoresis revealed that LTIP was found predominantly in particles in the size range of HDL. This unique HDL subclass may play an important role in the regulation of plasma lipid transfer and metabolism. 相似文献
10.
Tokuma Yanai Haruaki Taniguchi Hiroki Sakai Kazunori Yoshida Naoto Kimura Akira Katou Yuji Oishi Toshiaki Masegi 《Journal of medical primatology》1996,25(4):309-312
Abstract: A rare case of bilateral adrenal myelolipomas in a female cotton-top tamarin is reported. Large bilateral masses in the adrenal glands were composed of mature adipose cells containing varying amounts of hematopoietic cells of the myeloid, erythroid, and megakaryocyte series. The gross and histologic features of this case closely resemble human “giant” adrenal myelolipomas. 相似文献