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91.
92.
Measurement of PO2 in liver using EPR oximetry 总被引:1,自引:0,他引:1
Jiang J.; Nakashima T.; Liu K. J.; Goda F.; Shima T.; Swartz H. M. 《Journal of applied physiology》1996,80(2):552-558
93.
Total flavonoid content (TFC) and cyanidin‐3‐glucoside (Cyd‐3‐glu) of seed and seed coat extract of 16 genotypes from five species of Carthamus were studied, and their major polyphenolic compounds and antioxidant activity of the seed coat extracts were determined using HPLC analysis and DPPH assay, respectively. Additionally, fatty acids composition of the seed oil was analyzed by GC. In general, TFC and Cyd‐3‐glu content of seed coat extracts were higher than those of seed extracts. A novel breeding line with black seed coat (named A82) depicted lower TFC (3.79 mg QUE/g DW) but higher Cyd‐3‐glu (24.64 mg/g DW) compared to the white and other seed‐pigmented genotypes. DPPH radical scavenging activity showed a strong association with Cyd‐3‐glu content (r = 0.84), but no correlation with TFC (r = ?0.32). HPLC analysis of seed coat extracts revealed that four compounds were dominant constituents including rutin (7.23 – 117.95 mg/100 g DW), apigenin (4.37 – 64.88 mg/100 g DW), quercetin (3.09 – 14.10 mg/100 g DW), and ferulic acid (4.49 – 30.41 mg/100 g DW). Interestingly, the genotype A82 with an appropriate polyunsaturated/saturated fatty acids index (5.46%) and a moderate linoleic fatty acid content (64.70%) had higher nutritional and pharmaceutical value than all the other genotypes. 相似文献
94.
Effect of association with adenylyl cyclase-associated protein on the interaction of yeast adenylyl cyclase with Ras protein. 总被引:2,自引:1,他引:1 下载免费PDF全文
F Shima Y Yamawaki-Kataoka C Yanagihara M Tamada T Okada K Kariya T Kataoka 《Molecular and cellular biology》1997,17(3):1057-1064
Posttranslational modification of Ras protein has been shown to be critical for interaction with its effector molecules, including Saccharomyces cerevisiae adenylyl cyclase. However, the mechanism of its action was unknown. In this study, we used a reconstituted system with purified adenylyl cyclase and Ras proteins carrying various degrees of the modification to show that the posttranslational modification, especially the farnesylation step, is responsible for 5- to 10-fold increase in Ras-dependent activation of adenylyl cyclase activity even though it has no significant effect on their binding affinity. The stimulatory effect of farnesylation is found to depend on the association of adenylyl cyclase with 70-kDa adenylyl cyclase-associated protein (CAP), which was known to be required for proper in vivo response of adenylyl cyclase to Ras protein, by comparing the levels of Ras-dependent activation of purified adenylyl cyclase with and without bound CAP. The region of CAP required for this effect is mapped to its N-terminal segment of 168 amino acid residues, which coincides with the region required for the in vivo effect. Furthermore, the stimulatory effect is successfully reconstituted by in vitro association of CAP with the purified adenylyl cyclase molecule lacking the bound CAP. These results indicate that the association of adenylyl cyclase with CAP is responsible for the stimulatory effect of posttranslational modification of Ras on its activity and that this may be the mechanism underlying its requirement for the proper in vivo cyclic AMP response. 相似文献
95.
Kaori Ishida Takashi Murakami Akira Mizuno Mitsuru Iida Masamichi Kuwajima Kenji Shima 《Regulatory peptides》1997,70(2-3):179-182
The effects of leptin on insulin secretion from pancreatic islets of Sprague–Dawley rats were examined in vitro. In a basal glucose medium (5.5 mM), insulin secretion from isolated islets was significantly decreased after addition of a recombinant leptin (80 nM) (3.20±0.14 nmol/10 islets/h) compared with that before the addition (4.41±0.30 nmol/10 islets/h). Although significant leptin suppression of insulin secretion was not observed under a glucose-stimulated (11.1 mM) condition, these results suggest that a negative feedback system may exist between leptin and insulin, which increases the production of leptin from adipose tissues. 相似文献
96.
Ali Eslami Behnam Meshgi Fatemeh Jalousian Shima Rahmani Mohammad Ali Salari 《The Korean journal of parasitology》2016,54(1):55-60
The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain. 相似文献
97.
98.
N Nakagawa H Yasuda K Yano S i Mochizuki N Kobayashi H Fujimoto N Shima T Morinaga D Chikazu H Kawaguchi K Higashio 《Biochemical and biophysical research communications》1999,265(1):158-163
Basic fibroblast growth factor (bFGF) induced osteoclast formation in co-cultures of mouse spleen cells and osteoblasts. Osteoclastogenesis inhibitory factor (OCIF) and a selective cyclooxygenase-2 (COX-2) inhibitor, NS-398, abolished bFGF-induced osteoclast formation. bFGF did not affect spleen cells, but it did affect osteoblasts, to stimulate osteoclast formation. Northern blot analysis revealed that bFGF up-regulated the expression of osteoclast differentiation factor (ODF) and COX-2 and down-regulated the expression of OCIF in primary osteoblastic cells. NS-398 abolished the increase of ODF mRNA, but it had no effect on the decrease of OCIF mRNA. NS-398 suppressed the binding of (125)I-labeled OCIF to osteoblastic cells treated with bFGF. Enzyme-linked immunosorbent assay showed that bFGF inhibited OCIF production by osteoblastic cells, and the inhibition was not affected by NS-398. We conclude that bFGF induces osteoclast formation by stimulating ODF production through COX-2-mediated prostaglandin synthesis and by suppressing OCIF production through a mechanism independent of prostaglandin synthesis. 相似文献
99.
100.
Tsutsumi H Katagi M Miki A Shima N Kamata T Nishikawa M Nakajima K Tsuchihashi H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,819(2):315-322
To prove the intake of recently controlled designer drugs, N-benzylpiperazine (BZP) and 1-(3-trifluoromethylphenyl)piperazine (TFMPP), a simple, sensitive and reliable method which allows us to simultaneously detect BZP, TFMPP and their major metabolite in human urine has been established by coupling gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS). GC-MS accompanied by trifluoroacetyl (TFA) derivatization and LC-MS analyses were performed after the enzymatic hydrolysis and the solid phase extraction with OASIS HLB, and BZP, TFMPP and their major metabolites, 4'-hydroxy-BZP (p-OH-BZP), 3'-hydroxy-BZP (m-OH-BZP) and 4'-hydroxy-TFMPP (p-OH-TFMPP), have found to be satisfactorily separated on a semi-micro SCX column with acetonitrile-40 mM ammonium acetate buffer (pH 4) (75:25, v/v) as the eluent. The detection limits produced by GC-MS were estimated to be from 50 ng/ml to 1 microg/ml in the scan mode, and from 200 to 500 ng/ml in the selected ion monitoring (SIM) mode. Upon applying the LC-ESI-MS technique, the linear calibration curves were obtained by using the SIM mode for all analytes in the concentration range from 10 ng/ml to 10 microg/ml. The detection limits ranged from 5 to 40 ng/ml in the scan mode, and from 0.2 to 1 ng/ml in the SIM mode. These results indicate the high reliability and sensitivity of the present procedure, and this procedure will be applicable for proof of intake of BZP and TFMPP in forensic toxicology. 相似文献