| 1 | Intravenous acid fibroblast growth factor protects intestinal mucosal cells against ischemia-reperfusion injury via regulating Bcl-2/Bax expression显示文摘AIM: To detect the effect of acid fibroblast growth factor (aFGF) on apoptosis and gene expression of bax and bcl-2 gene in rat intestine after ischemia/reperfusion (I/R) injury, and to explore the protective mechanisms of aFGF.METHODS: One hundred and eight Wistar rats were randomly divided into sham-operated control group (C)(n = 6), intestinal ischemia group (I) (n = 6), aFGF treatment group (A) (n = 48) and intestinal ischemia reperfusion group (R) (n = 48). In group I, the animals were killed after 45 min of superior mesenteric artery (SMA) occlusion, while in groups R and A, the rats sustained 45 min of SMA occlusion and were then treated with normal saline and aFGF, respectively, sustained 15 min, 30 min, 1, 2, 6, 12, 24, or 48 h of reperfusion, respectively. In group C, SMA was separated, but without occlusion. Apoptosis in intestinal villus was determined with terminal deoxynucleotidyl transferase mediated dUTP-biotin nickend labeling technique (TUNEL). Intestinal tissue samples were taken not only for detection of bax and bcl-2 gene expression by RT-PCR, but also for detection of bax and bcl 2 protein expression and distribution by immunohistochemical analysis.RESULTS: The rat survival rates in aFGF treated group were higher than group R (P<0.05) and the improvement of intestinal histological structures was observed at 2, 6, and 12 h after the reperfusion in group A compared with group R. The apoptotic rates were (41.17±3.49)%, (42.83±5.23)% and (53.33±6.92)% at 2, 6 and 12 h after reperfusion, respectively in group A, apparently less than those of group R at matched time points (50.67±6.95, 54.17±7.86, 64.33±6.47, respectively) (P<0.05). The bax gene transcription and translation were significantly decreased in group A vs group R, while mRNA and protein contents of Bcl-2 in group A were obviously higher than those in groupR during 2-12 h period after reperfusion.CONCLUSION: The changes in histological structure and the increment of apoptotic rate indicated that the intestinal barrier was damaged after intestinal I/R injury, whilst intravenous aFGF could alleviate apoptosis induced by ischemia and reperfusion in rat intestinal tissues, in which genes of bax and bcl-2 might play important roles. | WeiChen Xiao-BingFu Shi-LiGe Tong-ZhuSun GangZhou BingHan Yi-RiDu Hai-HongLi Zhi-YongSheng | 2005 | World Journal of Gastroenterology2005，11，22： | 10 |
| 3 | Tertiary Calcareous Nannofossil Biostratigraphy in the North Part of the South China Sea显示文摘The marine Tertiary sequence in the north part of the South China Sea may be divided into 18 LateOligocene to Pliocene calcareous nannofossil zones and one unnamed Eocene assemblage based on an analysisof calcareous nannofossils from 40 offshore boreholes. The unnamed Eocene assemblage has been found onlyon the northeast margin of the Zhujiangkou basin. The 18 cakareous nannofossil zones of the Late Oligoceneto Pliocene were deposited in succession, but their development degrees are different. Among the 18 calcareousnannofossil zones, those corresponding to Martini’s (1971) NN4- NN5 zones, NN11 zone and NN13-NN15zones are well developed, relatively persistent laterally and also widely distributed. They are the importantmarkers for the stratigraphical subdivision and correlation of the Upper Tertiary between the various basins inthe north part of the South China Sea. Based on the calcareous nannofossils and the sedimentsry features coup-led with the foraminifer zonation in certain basins, the present paper discusses the sedimentary characteristicsof the marine Tertiary and as well as the distribution and development of the sedimentary hiatus in the region.The calcareous nannofossil markers for the Upper / Lower Tertiary and the Quaternary / Tertiary boundaries,and the characteristics and geological significance of the reworked calcareous nannofossils are also discussed inthe paper. | Duan Weiwu and Huang Yongyang Gangzhou Marine Geological Survey, Ministry of Geology and Mineral Resources, Guangzhou Chang Zhijun and Sun Sheping | 1991 | Acta Geologica Sinica(English Edition)1991，65，3： | 1 |
| 4 | THE DETERMINATION OF ADSORPTION ISOTHERMS AND SOLID DEFFUSION COEFFICIENTS OF MANNITOL AND SORBITOL BY LIQUIDCHROMATOGRAPHY TECHNIQUE显示文摘The Parameter identification model is proposed for determining the linear adsorptionisotherms and the solid diffusion coefficients by using adsorption chromatography. Axialdispersion coefficients is firstly determined by pulse-respond experiment technique with aninert substance as tracer then the elution curves of chromatography separating the isomermannitol and sorbitol are determined by the chromatographic measuring technique, andfinally the adsorption isotherms and the solid diffusion coefficients of mannitol andsorbitol on Ca2+ resins are estimated by using this model. The results show that the axialdispersion coefficients increase with fluid velocity increasing, the adsorption equilibriumconstants decrease with temperature rising;and the solid diffusion coefficients increasewith temperature rising. The theoretical elution curves are good agreement with theexperimental elution curves of the liquid adsorption chromatography separating themannitol and the sorbitol. The model provides a simple and reliable procedure to estimatethe kinetic and thermodynamic parameters of the adsorption. | ZHAO Yuechun XI Hongxia XIE Liansong LI Zhong(Research Institute of Chemical EngineeringSouth China University of Technology Gangzhou 510640 P R. China) | 1999 | Chinese Journal of Reactive Polymers1999，8，1： | 0 |
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