漾濞泡核桃ISSR-PCR反应体系的建立和优化

以漾濞泡核桃优株为研究对象,研究其ISSR-PCR反应体系中的5个影响因子(模板DNA浓度、Taq DNA聚合酶浓度、引物浓度、dNTPs浓度、Mg2+浓度)对PCR扩增效果的影响,从而建立起漾濞泡核桃的最佳ISSR-PCR反应体系。结果表明:模板DNA最佳浓度为50 ng/(25μL),Taq聚合酶浓度为0.75U/(25μL),引物浓度为0.7mmol/L,dNTPs浓度为0.20mmol/L,Mg2+浓度为2.0mmol/L,利用该最佳体系对试验中所选取的样本进行扩增反应。建立了适宜于漾濞泡核桃的ISSR-PCR扩增的最佳体系,该体系的建立为利用ISSR分子标记技术对漾濞泡核桃进行种质资源研究奠定了基础。     

17个甘蓝型油菜品种抗寒性的电导法测定

采用电导法对17个甘蓝型油菜品种的抗寒性进行了研究,并对低温处理后各品种电解质的外渗率及其临界致死低温进行了分析。结果表明,这17个油菜品种的抗寒性由强到弱依次为:沣油792沪油21中农油2008德油8号沣油730沣油682中双11号中双4号华油杂9号浙双3号沣油958华湘油12号秦优9号沣油520沣油5103沣油737华航901;上述前9个品种在湖南可自然越冬,后3个品种在湖南推广宜避开湘北地区,中等耐低温的其余5个品种在湖南湘北地区推广时宜采取有效的栽培技术措施来控制低温冻害。     

食品源保鲜剂对凤凰水蜜桃保鲜效果的研究

采取直接喷果的方式,观测和比较了两种食品源保鲜剂生姜浸提液和花椒浸提液对白花水蜜桃(Prunus persica)采后保鲜品质的影响,果实处理后装入保鲜袋置于常温条件下(28~30℃),24 h后测量其生理指标。结果表明:花椒浸提液保鲜效果最优,生姜浸提液保鲜效果次之,均好于对照组。而且,这两种方法简便可行,相对安全,因此,对凤凰水蜜桃而言,两种农艺方法均为有效且无污染的生物保鲜剂,特别是花椒浸提液,适宜推广应用。     

鳗鱼中磺胺类药物残留的Charm II放射免疫法检测

本文探讨应用Charm II放射免疫分析方法检测鳗鱼中磺胺类药物残留。确定鳗鱼检测的制样和控制点设定的方法,评价了免疫反应体系的灵敏度和特异性,验证了磺胺类最大残留限量50μg/kg的检测稳定性,90分钟可出检测结果。     

反刍动物微生态制剂研究进展.

微生态制剂通过改善反刍动物瘤胃及肠道微生态平衡,促进营养物质吸收,增强机体免疫和抗热应激能力。利用微生态制剂减少抗生素的使用量,符合人们对绿色、安全食品的需求,从而越来越受到人们的关注。本文综述了微生态制剂的作用机理,以及在反刍动物中的应用,并对其未来的前景和研究方向进行了分析。     

生物菌菇饲料对幼兔生产性能及血常规指标的影响

为研究生物菌菇饲料对幼兔生产性能的影响,选择健康、日龄相近的新西兰断奶幼兔144只,随机分为4个处理,对照组、试验1、试验2、试验3组日粮中分别含0%、8%、11%和14%的生物菌菇饲料替代麦麸,试验期30天。结果表明本试验条件下,生物菌菇饲料在断奶幼兔日粮中的用量过大对其血常规指标和存活率有一定的影响,建议添加量以不超过8%为宜。     

环境应激对肉鸡的影响和对策

在规模化养殖模式下,肉鸡不可避免地受到不同环境因子的影响而产生应激,环境应激直接影响肉鸡养殖的生产性能和产品质量.本文总结了几种常见环境应激因子对肉鸡健康状况、生产性能、免疫性能、血液生理生化指标、肉品质和机体器官等的影响以及降低肉鸡环境应激的主要技术措施,为有效降低环境应激、提高肉鸡养殖效益提供参考.     

Effect of captopril on AGS nude mouse model of gastric cancer

AIM: To observe the effect of captopril on the genesis and development of gastric cancer, and to explore its clinical treatment feasibility for gastric cancer. METHODS: The human gastric cancer cell line AGS was used to establish a tumor model in nude mice, and the model mice were randomly divided into 3 groups: positive control (5-fluorouracil) group, normal control (saline) group and experimental (captopril) group. After intraperitoneal injection or intragastric administration of the drugs, the tumor growth curve was determined, and the tumor tissues were also sampled to detect the expression of Ki-67, STAT3, Bax and Bcl-2 by real-time quantitative PCR and immunohistochemistry. The apoptosis was detected by TUNEL+DAPI staining. RESULTS: The tumor growth curve showed that the tumor model in the nude mice was successfully established. The tumor volumes among groups showed significantly different after 14 d growth. The increase in the tumor volume in normal control group was significantly faster than that in the other two groups, and that in positive control group was the slowest. The expression of Bax in captopril group increased, and the expression of STAT3, Ki-67 and Bcl-2 was reduced as compared with normal control group and positive control group. Compared with normal control group, the apoptotic rate increased significantly, and the protein expression of p-STAT3 and STAT3 decreased obviously in positive control group and captopril group. CONCLUSION: With better feasibility, angiotensin-converting enzyme inhibitor captopril has a significant effect on treating gastric cancer in the AGS nude mouse model by regulating the expression of STAT3, Bax, Bcl-2 and Ki-67 to accelerate the apoptosis of cancer cells, thus inhibiting tumor growth.     

Hydrogen sulfide ameliorates high glucose-induced endothelial cell senescence by suppressing oxidative stress

AIM：To explore the effect of hydrogen sulfide on the senescence of human umbilical vein endothelial cells (HUVECs) induced by high glucose. METHODS：Senescence model was established by treating HUVECs with 33 mmol/L glucose for 48 h. The parameters were detected to demonstrate the effect of hydrogen sulfide on senescence and the mechanism involved was also investigated. RESULTS：In the cells treated with high glucose, the proliferation was attenuated with a higher number of senescence-associated β-galactosidase (SA-β-Gal) positive cells, and plasminogen activator inhibitor 1 (PAI-1) protein expression, malondialdehyde (MDA) production and NF-κB p65 activity were increased significantly, but the expression of superoxide dismutase 1 (SOD1) was decreased. However, the cell number and SOD1 expression were increased, and the number of SA-β-Gal positive cells, PAI-1 protein expression, MDA production and the activity of NF-κB p65 were decreased after sodium hydrosulfide (100 and 200 μmol/L) treatment.CONCLUSION：Exo-genous hydrogen sulfide prevents HUVECs against high glucose-induced senescence by suppressing oxidative stress and NF-κB p65 activity.