AIM: Cyclooxygenase (COX)-2 is over expressed ingastrointestinal neoplasm. Helicobacter pylori ( H pylon)infection is causally linked to gastric cancer. However, theexpression of COX-2 in various stages of Hpylori-ass...AIM: Cyclooxygenase (COX)-2 is over expressed ingastrointestinal neoplasm. Helicobacter pylori ( H pylon)infection is causally linked to gastric cancer. However, theexpression of COX-2 in various stages of Hpylori-associatedgastric carcinogenesis pathway has not been elucidated.Therefore, the aim of this study was to clarify the role ofH pyloriinduced COX-2 expression during carcinogenesisin the stomach.METHODS: Gastric biopsies from 138 subjects [30 casesof chronic superficial gastritis (CSG), 28 cases of gastricglandular atrophy (GA), 45 cases of gastric mucosal intestinalmetaplasia (IM), 12 cases of moderate gastric epithelialdysplasia and 23 cases of gastric cancer] were enrolled.Hpyloriinfection was assessed by a rapid urease test andhistological examination (modified Giemsa staining). Theexpression of COX-1 and COX-2 in human gastric mucosawas detected by immunohistochemical staining.I^7~I_~: Hpyloriinfeddon rate was 64.3% in GA and 69.5%in gastric cancer, which was significantly higher than that(36.7%) in CSG (P<0.05). The positive expression rates ofCOX-2 were 10.0%, 35.7%, 37.8%, 41.7% and 69.5% inCSG, GA, IM, dysplasia and gastric cancer, respectively.From CSG to GA, IM, dysplasia and finally to gastric cancer,expression of COX-2 showed an ascending tendency, whereasCOX-1 expression did not change significantly in the gastricmucosa. The level of COX-2 expression in IM and dysplasiawas significantly higher in H pylon:positive than in H pylor/-negative subjects (P<0.01).展开更多
The solvent extraction of uranium(VI) and europium(III) from nitric acid solution was studied with pi- colinamide dissolved in ethylene dichloride. The distribution ratios of U(VI) and Eu(III) as a function of aqueous...The solvent extraction of uranium(VI) and europium(III) from nitric acid solution was studied with pi- colinamide dissolved in ethylene dichloride. The distribution ratios of U(VI) and Eu(III) as a function of aqueous HNO3 concentration , extractant concentration in organic phase and temperature as well as the salting-out agent con- centration have been measured. The experiment results show that picolinamide has higher extractability for U(VI) than for Eu(III). The composition of extracted species, equilibrium constants and enthalpies of extraction reaction have also been presented.展开更多
基金Supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,No.9247342057
文摘AIM: Cyclooxygenase (COX)-2 is over expressed ingastrointestinal neoplasm. Helicobacter pylori ( H pylon)infection is causally linked to gastric cancer. However, theexpression of COX-2 in various stages of Hpylori-associatedgastric carcinogenesis pathway has not been elucidated.Therefore, the aim of this study was to clarify the role ofH pyloriinduced COX-2 expression during carcinogenesisin the stomach.METHODS: Gastric biopsies from 138 subjects [30 casesof chronic superficial gastritis (CSG), 28 cases of gastricglandular atrophy (GA), 45 cases of gastric mucosal intestinalmetaplasia (IM), 12 cases of moderate gastric epithelialdysplasia and 23 cases of gastric cancer] were enrolled.Hpyloriinfection was assessed by a rapid urease test andhistological examination (modified Giemsa staining). Theexpression of COX-1 and COX-2 in human gastric mucosawas detected by immunohistochemical staining.I^7~I_~: Hpyloriinfeddon rate was 64.3% in GA and 69.5%in gastric cancer, which was significantly higher than that(36.7%) in CSG (P<0.05). The positive expression rates ofCOX-2 were 10.0%, 35.7%, 37.8%, 41.7% and 69.5% inCSG, GA, IM, dysplasia and gastric cancer, respectively.From CSG to GA, IM, dysplasia and finally to gastric cancer,expression of COX-2 showed an ascending tendency, whereasCOX-1 expression did not change significantly in the gastricmucosa. The level of COX-2 expression in IM and dysplasiawas significantly higher in H pylon:positive than in H pylor/-negative subjects (P<0.01).
文摘The solvent extraction of uranium(VI) and europium(III) from nitric acid solution was studied with pi- colinamide dissolved in ethylene dichloride. The distribution ratios of U(VI) and Eu(III) as a function of aqueous HNO3 concentration , extractant concentration in organic phase and temperature as well as the salting-out agent con- centration have been measured. The experiment results show that picolinamide has higher extractability for U(VI) than for Eu(III). The composition of extracted species, equilibrium constants and enthalpies of extraction reaction have also been presented.
