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61.
A Yamakawa M Nishizawa K T Fujiwara S Kawai H Kawasaki K Suzuki T Takenawa 《The Journal of biological chemistry》1991,266(26):17580-17583
A complementary DNA (cDNA) clone that encodes phosphatidylinositol 4-kinase (PI 4-kinase) was isolated from a rat brain cDNA library. The deduced amino acid sequence of 697 residues revealed that the protein contains two putative transmembrane sequences and that the N-terminal part of the protein has several sequences representing potential phosphorylation sites for cAMP- and calmodulin-dependent kinase. The C-terminal region is probably a phosphotransferase domain homologous to the kinase region of protein kinase family proteins. Specific antibody against the protein expressed in Escherichia coli successfully immunoprecipitated rat brain PI 4-kinase. The messenger RNA for PI 4-kinase was found predominantly in brain and rat neural cell lines. This PI kinase may play a specific role in neural signal transduction. 相似文献
62.
K Kawai A Fukamizu Y Kawakami M Matsumura K Mitsui K Murakami K Yamashita 《Endocrinologia japonica》1991,38(6):603-609
A 54-year-old woman was referred to our hospital for the treatment of a tumor of the right chest wall. Clinical examination revealed hypertension, hypokalemia, metabolic alkalosis, hyperaldosteronism and hyperreninemia. Computed tomography and an abdominal echogram indicated a tumor in the right phrenic area and two tumors in the retroperitoneum near the pancreas head. After the surgical resection of these tumors, the primary reninism was diminished. The pathological diagnosis of these tumors was leiomyosarcoma. Plasma active and inactive (trypsin-activated) renin activities (PRA) were 85.7 and 38.9 ng angiotensin I/ml/h, respectively. These PRA did not respond to either postural stimulation or suppression by the volume expansion. Active and inactive renin activities in a right phrenic area tumor were 208 and 32 ng angiotensin I/mg protein /h, respectively. Those of an abdominal tumor were 196 and 30 ng angiotensin I/mg protein/h, respectively. Renin mRNA identical in molecular size to that of the human kidney was identified by northern blot analysis. This is the first case report of renin producing leiomyosarcoma derived from the lung, which is characterized by relatively lower plasma prorenin concentrations. 相似文献
63.
Kuriyama Akira; Takeuchi Masayuki; Kawai Fumio; Kanamori Masao 《Plant & cell physiology》1992,33(5):647-650
The formation of sporophytic shoots, which is induced by treatmentwith benzylaminopurine of gametophyte tissue of Equisetum arvense,can be divided into initiation and developmental phases. Thenitrogen in MS medium was suitable for two phases as well as gametophytic growth, buta reduction in the concentration of available nitrogen was neededfor the development of shoots. ions alone were effective for gametophytic growth and the initiationof sporophytic shoots, but both and ions was required for the developmental phase. (Received February 18, 1992; Accepted April 14, 1992) 相似文献
64.
Kunshan Gao Yusho Aruga Kozi Asada Toshiaki Ishihara Toru Akano Masataka Kiyohara 《Journal of applied phycology》1991,3(4):355-362
Leafy thalli of the red algaPorphyra yezoensis Ueda, initiated from conchospores released from free-living conchocelis, were cultured using aeration with high CO2. It was found that the higher the CO2 concentration, the faster the growth of the thalli. Aeration with elevated CO2 lowered pH in dark, but raised pH remarkably in light with the thalli, because the photosynthetic conversion of HCO 3 ? to OH? and CO2 proceeded much faster than the dissociation of hydrated CO2 releasing H+. Photosynthesis of the alga was found to be enhanced in the seawater of elevated dissolved inorganic carbon (DIC, CO2 + HCO 3 ? + CO 3 ? ). It is concluded that the increased pH in the light resulted in the increase of DIC in the culture media, thus enhancing photosynthesis and growth. The relevance of the results to removal of atmospheric CO2 by marine algae is discussed. 相似文献
65.
Atrial natriuretic peptide reduces the basal level of cytosolic free Ca2+ in guinea pig cardiac myocytes 总被引:4,自引:0,他引:4
M Tei M Horie T Makita H Suzuki A Hazama Y Okada C Kawai 《Biochemical and biophysical research communications》1990,167(2):413-418
The cytosolic free Ca2+ concentration ([Ca2+]i) was monitored in quiescent atrial and ventricular myocytes isolated from guinea-pig hearts by the fura-2 fluorescence ratio technique. Recombinant human atrial natriuretic peptide (ANP) was found to reduce their basal [Ca2+]i level in a dose-dependent manner. Dibutyryl-cGMP mimicked the effect of ANP. Neither the prior application of caffeine nor removal of extracellular Na+ impaired the ANP effect. ANP had no inhibitory effect on voltage-gated Ca2+ currents measured by a whole-cell patch clamp technique. The ANP-induced [Ca2+]i decrease was abolished by orthovanadate. Thus, it is concluded that ANP reduces the basal [Ca2+]i presumably through the cGMP-mediated activation of the plasma membrane Ca2(+)-pump in cardiac myocytes. 相似文献
66.
Identification of a membrane glycoprotein overexpressed in murine lymphoma sublines resistant to cis-diamminedichloroplatinum(II) 总被引:2,自引:0,他引:2
A series of murine thymic lymphoma cell sublines was selected in vitro for resistance to cis-diamminedichloroplatinum(II) (CDDP). The level of CDDP resistance correlated with reduced drug accumulation in these cells. A rabbit antiserum was raised against the plasma membrane of a CDDP-resistant subline and used in Western blot analyses. Increased expression of a surface antigen of approximately 200 kDa was observed and found to correlate with the degree of resistance. Further biochemical and immunological studies demonstrated that this is a plasma membrane glycoprotein. However, it is different from the multidrug resistance-associated P-glycoprotein with a molecular weight of about 170,000. We have called this unique CDDP resistance-associated membrane protein CPR-200. 相似文献
67.
K Kawai H Mukai K Yuzawa S Suzuki N Kuzuya K Fujii E Munekata K Yamashita 《Endocrinologia japonica》1990,37(6):857-865
A study relating to gastrin release from gastrinoma cells by neuromedin B and C-terminal decapeptide of gastrin releasing peptide (GRP-10) has not yet been reported. Therefore, we studied the effects of neuromedin B and GRP-10 on gastrin release from cultured dispersed cells prepared from both the primary tumor in the pancreas and the metastatic tumor in the liver from a case of malignant Zollinger-Ellison syndrome. Both the primary and metastatic tumors obtained by a curative operation contained similar concentrations of gastrin and glucagon, whereas the primary tumor contained 10 times more insulin than the metastatic tumor. Gastrin release from cultured cells of both tumors was suppressed by 0.1 and 10 nM neuromedin B and tended to be suppressed by 0.1-10 nM GRP-10. However, insulin release from cultured cells of the pancreatic tumor was stimulated by GRP-10, but not by neuromedin B. These results might suggest that receptor function for the bombesin family peptides is abnormal in gastrinoma cells in both primary and metastatic tumors, and that a major source of insulin secretary cells is the contaminated normal islet cells in the primary tumor. 相似文献
68.
M. Akaboshi K. Kawai H. Maki K. Kawamoto Y. Honda 《Origins of life and evolution of the biosphere》1982,12(4):339-345
Ammonium acetate in various conditions was irradiated in a reactor to examine the contributions of both the reactor radiations and recoiled14C nucleis to form the biologically interesting molecules. Present investigations demonstrated that several amino acids, glycine, alanine, -alanine and GABA, and may-be aspartic acid, serine and valine by prolonged irradiation, were formed in the aqueous solutions of ammonium acetate.14C-radioactivities were also found distributed in these amino acids. However, no special relationship between14C-radioactivity and these amino acids formed was observed. 相似文献
69.
Preparation of Uridine Diphosphate-N-Acetylgalactosamine from Uridine Diphosphate-N-Acetylglucosamine by Using Microbial Enzymes 下载免费PDF全文
A method was developed for the large scale preparation of uridine diphosphate-N-acetylgalactosamine (UDP-GalNAc) from uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) by means of microbial enzymes. With Bacillus subtilis cell-free extract as a source of UDP-GlcNAc 4-epimerase, about 35% of the UDP-GlcNAc added was converted to UDP-GalNAc. After the residual UDP-GlcNAc was degraded to uridine triphosphate and N-acetylglucosamine-1-phosphate with a protamine-treated extract of bakers' yeast as a source of UDP-GlcNAc pyrophosphorylase, UDP-GalNAc was separated by anion-exchange column chromatography. The nucleotide was recovered by adsorption on charcoal and elution with ammoniacal ethanol. The final yield was about 100 μmol. 相似文献
70.
Yoshiteru Harada Kunio Tanaka Yasushiro Uchida Akinori Ueno Sachiko Oh-ishi Yamashita Kowa Masataka Ishibashi Hiroshi Miyazaki Makoto Katori 《Prostaglandins & other lipid mediators》1982,23(6)
Injection of γ-carrageenin into t he pleural cavity of rats caused the accumulation of the pleural exudate. When levels of prostaglandins (PGs) and thromboxane (TX) B2 were quantified by gas chromatography-mass spectrometry as their methyl ester (ME)-dimethyllisopropylsilyl (DMiPS) ether or ME-methoxine-DMiPS ether derivatives, 6-keto-PGF1α reached the maximum at 1 hr after carrageenin, then PGE2 and TXB2 showed peaks at 3 hr and waned off before 9 hr. he PGF2α level was kept low, but PGD2, PGE1 and PGF1α were not detected. Aspirin (100 mg/kg, i.p.) significantly decreased the PG and TXB2 levels and suppressed the rate of plasma exudation until 5 hr, but did not at 7 hr, when it was measured by the amount of exuded pontamine sky blue injected intravenously. OKY-025 (300 mg/kg, i.p.), a selective TXA synthetase inhibitor, and tranylcypromine (20 mg/kg, i.p.), a PGI synthetase inhibitor, could not extensively inhibit the accumulation of the exudate. These results suggest that the cyclooxygenase products of arachidonic acid, particularly PGE2, definitely play an important role in the exudation during the first 5 hr. 相似文献