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91.
AIM: To explore the effect and mechanism of preoperative transarterial chemoembolization on nephroblastoma.METHODS: Comparative analysis of clinical and pathological features in 39 children with Wilms’ tumor was conducted.TUNEL assay was used to detect the apoptosis of tumor in two groups with or without preoperative interventional treatment.The expressions of P53,Bcl-2 and Bax proteins were detected by immunochemical methods.The patients were followed-up for more than 2 years.RESULTS: The extent of neoplastic cell necrosis and degeneration,interstital fiber tissue hyperplasia of tumor and the number of infiltrating lymphocytes were observed,which were higher in interventional group than those in simple excision group (P<0.01).The median of mitotic index in tumor cells was 0.2 in interventional group,and 1.4 in simple excision group.The median of apoptotic index (AI) of the tumor cells was 25.9 in study group and 12.8 in control group (Uc=54.50,P<0.01),(Uc=117.00,P<0.05).The comparison between the means obtained in two groups revealed statistical difference (P<0.05).The expressions of P53 and Bcl-2 proteins were not correlated with apoptotic index,but the rate of expression of Bax protein (80.0%) in interventional group was higher than that (40.0%) in simple excision group.The two year event-free rate was 73.3% (11/15) in study group and 42.9% (6/14) in control group.CONCLUSION: Transarterial chemoembolization on nephroblastoma is effectively used to kill and inhibit tumor cell growth,as well as induce tumor cell apoptosis by Bax protein.  相似文献   
92.
AIM: To explore the effect of recombinant human epidermal growth factor (rhEGF) on the ERK1/2 pathway and its safety in use when the proliferation of cultured FL cells (human amnion epithelial cells) were promoted by rhEGF.METHODS: FL cells were stimulated by rhEGF at various concentrations.The proliferation rate of FL cells was evaluated by MTT assay.Western blotting was used to detect phosphorylation of ERK1/2 (p-ERK1/2) and the change of Bcl-2 and P53 protein.RESULTS: The proliferation rate FL cells reached the maximum when the concentration of rhEGF was 10 μg/L (42.4%,P<0.01).Western blotting showed that the activity of p-ERK1/2 increased significantly when rhEGF ranged in 10 μg/L to 60 μg/L.Level of Bcl-2 was unchanged in each groups.Level of P53 decreased significantly when the concentration of rhEGF was 60 μg/L.CONCLUSION: It is safe when rhEGF presents in optimization concentration of 10 μg/L.The capability of apoptosis may be depressed when rhEGF is in larger dose.  相似文献   
93.
AIM: To study the effect of late reperfusion on apoptotic cardiomyocytes in the risk area of acute myocardial infarctin in dogs. METHODS: The experiment was divided into three groups: sham operation group, acute myocardial infarction (AMI) group, and late reperfusion (LR) group. Apart from sham operation group, the other two groups were subjected to left anterior descending branch of coronary artery ligation. The acute myocardial infarction group was only subjected to ligation for 12 hours, late reperfusion group was subjected to ligation for 6 hours following by 6 hours of reperfusion. The cardiomyocyte apoptosis was measured by TUNEL assay. Immunohistochemistry and Western blotting analysis were used to detect the expression of Bcl-2 and Bax protein. RESULTS: The number of apoptotic cardiomyocytes in late reperfusion group was much less than acute myocardial infarction group (P<0.05), and increased significantily as compared with sham operation group (P<0.01). The expression of Bcl-2 protein was enhanced gently in late reperfusion group in contrast to acute myocardial infarction group, but no significant difference in the two groups (P>0.05) was observed, although it was much more in the two groups than that in sham operation group (P<0.01). The expression of Bax protein in late reperfusion group was much higher than that in sham operation group (P<0.01), and was lower than that in acute myocardial infarction group (P<0.05). CONCLUSION: Late reperfusion reduces cardiomyocyte apoptosis in the risk area of acute myocardial infarction. The mechanism may be that late reperfusion can decrease the expression of Bax protein.  相似文献   
94.
AIM: To investigate the relationship between hemin and Erk1/2 activation in human umbilical vascular endothelial cells (HUVECs). METHODS: Cultured HUVECs were separately incubated with hemin or H2O2 for different times. Subsequently Erk1/2 phosphorylation and total Erk1/2 were determined by Western blotting assay. Flow cytometry was employed to determine the cell cycle distribution. RESULTS: Hemin at the concentration of 1-10 μmol/L induced the phosphorylation of Erk1/2 in HUVECs, and sustained the phosphorylation of Erk1/2 for three hours. The duration of phospho-Erk1/2 induced by hemin was much longer than that in H2O2 control (3 h vs 30 min). CONCLUSION: Hemin induces and sustains the phosphorylation of Erk1/2 in HUVECs, which indicates that the effect of hemin on the Erk1/2 activation may be one of pharmacological target of hemin.  相似文献   
95.
日粮能量和蛋白水平对肉鸡腹脂和血脂的影响   总被引:28,自引:2,他引:26  
对708只(公、母各半)5~9周龄黄羽肉鸡进行3个代谢能水平(13.4,12.5,11.6MJ/kg)和3个粗蛋白水平(22.4%,19.4%,16.4%)交叉的饲养试验,以探讨日粮代谢能和粗蛋白水平时黄羽肉鸡腹脂和血脂水平的影响。日粮代谢能和粗蛋白水平对腹脂有明显影响,腹脂随日粮代谢能水平的升高而升高(P<0,01)。随粗蛋白水平的升高而降低(P<0.05)。日粮能量和蛋白水平对板油的影响与腹脂相似。日粮代谢能水平对肌胃脂无明显影响;日粮粗蛋白水平对肌胃脂重无明显影响,但对肌胃脂率有一定影响(P=0.07)。日粮粗蛋白和代谢能水平对血浆极低密度脂蛋白(VLDL)、甘油三酯、胆固醇及总脂浓度均有显著影响(P<8.05),8周龄血浆VLDL浓度随日粮代谢能的升高而降低(P<0.0001);血浆总脂和胆固醇浓度均随日粮代谢能、粗蛋白水平的升高而降低(P≤0.001)。肉鸡8周龄血浆VLDL水平明显存在日粮能量和蛋白的互作效应(P<0.01),而血浆甘油三酯、胆固醇和总脂水平不存在明显的能量和蛋白的互作(P>0.05)。  相似文献   
96.
牦牛瘤胃内饲料蛋白质降解率的研究   总被引:3,自引:0,他引:3  
用瘤胃尼龙袋技术测定了11种常见饲料在牦牛瘤胃内的降解率。根据饲养水平,瘤胃食糜的外流速度估计为0.067/h。测定结果表明,玉米、豌豆秸粉、菜籽饼、豌豆、鱼粉、曲拉、肉骨粉、青稞、甲醛鱼粉、甲醛菜籽饼和麸皮的粗蛋白(CP)降解率分别为0.68、0.56、0.44、0.85、0.49、0.55、0.81、0,83、0.38、0,48和0.79,干物质(DM)降解率依次为0.68、0.30、0.49、0.73、0.50、0,54、0,59、0.82、0.32、0.49和0.74。  相似文献   
97.
娄义龙  高嘉麟 《园艺学报》1998,25(4):385-390
1993~1997年研究表明,在贵阳地区,适应性较强的唐菖蒲浅色花品种的休眠球茎、发芽种球、幼苗期球茎及幼苗根的超氧化物歧化酶活性高于适应性较弱的深色花品种,而深色花品种的开花期母球、新球、新根、茎、叶、花药的蛋白质含量以及上部叶片的光饱和点、净光合速率、光呼吸速率、暗呼吸速率高于浅色花品种,花瓣的蛋白质含量低于浅色花品种。由此推测,唐菖蒲不同品种的栽培适应性差异与以上生理生化性状差异有关。  相似文献   
98.
Ileal indigestible protein may be an important factor for the occurrence of post weaning diarrhoea in piglets. Depending on the quantity of indigested protein, an imbalance in the microbial community can occur, resulting in an overgrowth of pathogens. Diet viscosity may influence nutrient digestibility and substrate availability for microbial growth. Therefore, we examined the effect of dietary viscosity in piglet nutrition. Carboxymethylcellulose (CMC) was added as a model substance in order to increase diet viscosity. The effect of 1% supplemented CMC on nutrient digestibility, morphological and physiological parameters was measured in piglets 3 weeks post weaning at 26 days of age. The main effects of inclusion of CMC were:
– A 10% slower gastric emptying rate (P = 0.18).

– An increased protein hydrolysis in the gastric fraction, measured as increased nitrogen concentration in the liquid phase of gastric contents (26% in control vs. 34% in experimental group; P = 0.13).

– An increased production of the protein hydrolysing enzyme amino-peptidase from 359 U/g protein for the control diet to 516 U/g protein for the experimental diet (P < 0.01).

– A numerical increase in apparent ileal protein digestibility by 6% from 75.2% to 79.5% (P = 0.22) and a significant increase in faecal protein digestibility by 5% (P = 0.044).

These results indicate that an optimized diet viscosity might be one factor exerting a beneficial influence on protein digestibility. We hypothesize that the effect of diet viscosity on gastric emptying rate is the major factor.  相似文献   

99.
冀豆12遗传背景导入系蛋白、脂肪含量分布特征   总被引:2,自引:0,他引:2  
以高蛋白品种冀豆12为受体亲本,不同来源、不同蛋白脂肪含量的大豆种质资源为供体亲本,构建了28个组合BC2F1后代群体,分析冀豆12遗传背景导入系后代蛋白、脂肪含量分布特征。结果表明,28个后代群体均有蛋白含量超高亲个体,超高亲个体比例介于4.0%~68.2%之间,超高亲比例≥40%的组合有18个,占64.3%,BC2F1后代群体蛋白含量以超高亲和偏高亲类型组合为主。而脂肪含量分布特征恰相反,BC2F1后代群体脂肪含量以超低亲和偏低亲类型组合为主,超高亲个体比例介于0~67.4%,超高亲个体比例≥40%的组合有7个,占25.0%,9个组合无超高亲后代。表明以冀豆12为遗传背景通过有限回交易选育高蛋白含量品种,而不易选育高脂肪含量品种。本研究结果为利用冀豆12培育高蛋白品种提供了依据。  相似文献   
100.
草菇低温诱导蛋白的初步研究   总被引:4,自引:2,他引:2  
低温诱导草菇(Volvariella volvacea)菌丝体一时间后,发现草菇在低温胁迫中产生了新的可溶性蛋白质。应用电泳分离制备技术,分离纯化了草菇菌丝体中的一个低温诱导蛋白。  相似文献   
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