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101.
102.
103.
Akt/PKB activation in gastric carcinomas correlates with clinicopathologic variables and prognosis 总被引:23,自引:0,他引:23
Nam SY Lee HS Jung GA Choi J Cho SJ Kim MK Kim WH Lee BL 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(12):1105-1113
Akt/protein kinase B (PKB) plays an important role in cell survival. However, the role of Akt in the biology of gastric cancer has not been well studied. We sought to investigate the expression of Akt or phosphorylated Akt (pAkt) in human gastric carcinomas and to analyze the relationship between Akt or pAkt and the clinicopathologic parameters. The expressions of Akt and pAkt were evaluated immunohistochemically in 311 gastric carcinomas using the tissue array method. Akt expression was detected in 74% of the tumors and pAkt expression in 78%. pAkt was highly expressed in the early stage of pTNM (p=0.011). We also found an inverse association between pAkt and lymphatic invasion (p=0.01) or lymph node metastasis (p=0.008). pAkt expression was significantly correlated with a higher survival in patients with stage I carcinomas (p=0.0003). Interestingly, combined evaluation revealed that the group with pAkt-positive and lymph node-negative carcinomas showed a better prognosis than the other groups (p<0.0001). In addition, pAkt was shown to correlate positively with APC (p=0.002) and Smad4 (p<0.0001) expression. These findings suggest that pAkt expression may help to predict the clinical outcome of gastric cancer patients. 相似文献
104.
Lee YJ Nam SW Seo DW Ahn SH Ko YK Sung DS Han JW Hong SY Lee HW 《Archives of pharmacal research》1997,20(3):239-246
In the present study, liver regeneration rate (%) was increased up to 70% 3 days after partial hepatectomy (PH). Nitric oxide
synthase (NOS) activity in liver tissue as well as serum nitrite/nitrate content had no timed response, revealing no significant
difference between shamoperated and partially hepatectomized rat liver. Contents of free methylarginines in liver tissue were
increased biphasically in a time-dependent manner after PH. However, those in serum did not exhibit the same patterns as in
liver. Taken together, the results suggest that NG-monomethyl-L-arginine (MMA) and NG, NG-dimethylarginine (DMA) play a role in inhibiting nitric oxide (NO) synthesis in regenerating rat liver because the increase
of their contents was synchronized with NOS expression. 相似文献
105.
The effect of the root ofCoptis japonica (COPT), both the dichloromethane soluble (CH2Cl2) and insoluble (H2O) fractions, on catecholamine contents and tyrosine hydroxylase (TH) activity in PC12 cells was investigated. CH2Cl2 and H2O fractions showed 21 and 53% inhibitions on dopamine content, respectively, at a concentration of 40 μg/ml in medium: the H2O fraction provided a greater inhibitory effect. The TH activity was reduced by the treatment of COPT (H2O fraction). These results suggest that COPT has an inhibitory effect on the catecholamine biosynthesis by the reduction of TH activity in PC12 cells. 相似文献
106.
The activity of S-famesylcysteine O-methyltransferase was assayed by incubating the enzyme with a syntheticin vitro substrate, [N-acetyl-S-trans, trans-famesyl-L-cysteine (AFC)], together with S-adenosyl-L-[methyl-14C]methionine. The resulting methylesterification product, [N-acetyl-S-trans, trans-famesyl-L-cysteine (methyl-14C) ester (AFCME)], was then analyzed either directly on HPLC or by converting the AFC[methyl-14C]ME to [methyl-14C] alcohol by basehydrolysis. Employing these two analytical methods, it was established that a peptide purified from rat liver cytosol fraction [Int. J. Biochem., 25, 1157 (1993)] strongly inhibited the above enzyme activity with IC50 of 7.1X10?8 M. Also, the S-famesylcysteine O-methyltransferase from several human colon cancer cells was also equally inhibited by the peptide. 相似文献
107.
108.
Metabolism and excretion of atorvastatin in rats and dogs. 总被引:1,自引:0,他引:1
Atorvastatin (AT) is a second-generation potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, clinically approved for lowering plasma cholesterol. Using a mixture of [D(5)/D(0)] AT and/or [(14)C]AT, the metabolic fate and excretion of AT were examined in rats and dogs following single and multiple oral doses. Limited biliary recycling was examined in one dog after a single dose of AT. AT-derived metabolites in bile samples were identified by metabolite screening of the [D(5)/D(0)] AT molecular clusters using tandem mass spectrometry. Bile was a major route of [(14)C] drug-derived excretion, accounting for 73 and 33% of the oral dose in the rat and dog, respectively. The remaining radioactivity was recovered in the feces; only trace amounts were excreted in urine. Radioactive components identified in rat and dog bile were the para- and ortho-hydroxy metabolites, a glucuronide conjugate of ortho-hydroxy AT, and unchanged AT. Two minor radioactive components were identified as beta-oxidation products of AT with one confirmed as a beta-oxidized AT derivative. The reappearance of AT and major metabolites in bile from a dog administered a sample of its previously excreted bile indicated biliary recycling is an important component in AT metabolism. Multiple dose administration in rats did not alter biliary metabolic profiles. Rat and dog plasma profiles after multiple dose administration were similar and showed no additional metabolites not found in bile. Examination of rat and dog bile and plasma indicates that AT primarily undergoes oxidative metabolism. 相似文献
109.
Lim YH Leem MJ Shin DH Chang HB Hong SW Moon EY Lee DK Yoon SJ Woo WS 《Archives of pharmacal research》1999,22(2):208-212
Activity-guided fractionation of the roots of Anthriscus sylvestris resulted in the isolation and characterization of five cytotoxic compounds, deoxypodophyllotoxin (1), falcarindiol (2), and angeloyl podophyllotoxin (5) from the hexane soluble fraction and morelensin (3), bursehernin (4) from the chloroform soluble fraction. It is the first report of the occurrence of compound 5 in nature. 相似文献
110.
Yong -Hyun Kim Do -Youn Won Chang -Young Oh Nam -Tae Woo Young -Ho Park Jin -Hyun Jeong Won -Hun Ham 《Archives of pharmacal research》1999,22(3):300-301
Stereoselective synthesis of (+/-)-epibatidine analog 2, which contains the 8-azabicyclo[3.2.1]octane ring system, was achieved by using palladium-catalyzed Heck-type coupling reaction from 3. 相似文献