不同海拔环境中藏鸡生长曲线及杂种优势分析

为研究藏鸡生长规律及生长性能杂种优势,测定了藏鸡、矮小隐性白肉鸡(低地肉鸡品种)及其杂交F1代在低海拔和高海拔环境中体重和胫长的生长数据,运用Richards模型拟合其生长规律。结果表明Richards比较适宜拟合鸡在高、低海拔环境中体重和胫长的生长模式,R2>0.99。高海拔环境会降低鸡的生长速度、拐点值、生长极限和最大日增长,延长拐点时间。藏鸡在低海拔极限体重、拐点体重和最大日增重分别为1008.3、477.9和11.69 g,在高海拔分别为525.0、229.5和5.12 g;分别降低了47.9%、52.0%和56.8%,但影响程度均低于低海拔品种矮小隐性白肉鸡,表现出高海拔适应性,其杂交F1代的体重生长参数有明显的杂种优势,尤其在高海拔环境中,极限体重、拐点体重和最大日增重杂种优势率分别达59.5%、56.8%和52.3%,是藏鸡杂交利用的良好组合。     

草莓果实发育过程中糖代谢相关基因的表达分析

 为了分析草莓（Fragaria × ananassa Duch.）果实发育过程中可溶性糖积累与相关基因表达量的关系,以‘杜克拉’草莓7个发育时期的果实为试材,利用实时荧光定量RT-PCR的方法,分析果实发育中蔗糖转运蛋白及糖代谢关键酶（酸性转化酶、蔗糖合成酶和蔗糖磷酸合成酶）4个基因的表达量以及可溶性糖含量的变化趋势。结果表明,蔗糖、葡萄糖和果糖含量随着果实发育都呈逐渐增加的趋势,尤其蔗糖积累与果实成熟的关系较密切。随着果实发育,蔗糖磷酸合成酶基因表达量呈逐渐增加的趋势,尤其在果实发育的后期增加较快;蔗糖合成酶和酸性转化酶基因表达量除了白熟期和转色期外,呈逐渐降低的趋势;蔗糖转运蛋白基因表达量呈先升后降,降后又升的变化趋势,尤其在白熟期前急剧增加。结合可溶性糖和基因变化趋势分析表明,蔗糖转运蛋白和蔗糖磷酸合成酶在草莓果实发育过程中发挥着重要的作用。     

板栗赤霉素缺陷型短雄花序芽变的初步鉴定及CmGID1基因的表达分析

 利用赤霉素、细胞分裂素、脱落酸、乙烯利和吲哚乙酸分别涂抹板栗短雄花序,结果显示仅赤霉素能够抑制短雄花序顶端的细胞程序性死亡,并在一定程度上恢复短雄花序的伸长生长。通过RT-PCR扩增方法,从板栗短雄花序芽变和正常雄花序cDNA中克隆出赤霉素受体基因GID1部分序列。测序及序列分析结果表明：克隆的cDNA片段为786 bp,所推导的氨基酸序列与杨毛果GID1氨基酸序列有91%的同源性,与陆地棉、蓖麻GID1均有85%的氨基酸序列同源性。经氨基酸序列功能分析,推测该GID1序列是板栗有编码功能的赤霉素受体基因,命名为CmGID1（GenBank登录号为HQ651231）。实时荧光定量PCR结果显示,从花序萌发至花药萌发前期,除其中一个时期（5月23日）外,芽变短雄花序CmGID1的表达量均高于正常雄花序;在花序的快速生长期,芽变短雄花序CmGID1表达量显著高于正常雄花序（P < 0.01）;且赤霉素处理后恢复生长的短雄花序CmGID1表达量显著降低（P < 0.01）。综合试验结果,初步揭示了该短雄花序为一个赤霉素缺陷型突变体。     

桃花芽休眠解除SSH文库构建及相关基因表达分析

 为了深入研究桃花芽休眠的分子机制,利用抑制差减杂交技术（SSH）,以解除休眠期的花芽的RNA为实验方Tester,以休眠期花芽的RNA为驱动方Driver,构建休眠解除cDNA文库,测定分析了180 个上调表达的cDNA 片段,测序成功128个,除去冗余序列,得到28个单一序列。对序列进行BLAST比对及功能注释,发现这些序列分别属于新陈代谢、氧化还原、信号转导、抗性相关等类别基因。运用qRT-PCR 技术对HisH3、Dhn 和Metallothionein基因进行检测,结果表明它们在花芽休眠解除过程中均上调表达。     

葡萄白藜芦醇主要衍生物的研究进展

 葡萄白藜芦醇的衍生物都源于白藜芦醇,但结构又不同于白藜芦醇,其中有些化合物具有与白藜芦醇相同或相似的药理活性,有些甚至强于白藜芦醇,在医学以及植物抗病等研究领域备受关注。因此,综述了这些物质的抗病作用、保健功能、检测方法以及诱导合成等方面的研究进展,以期为深入研究奠定基础。     

Expression of EAAT3 in prefrontal cortex and hippocampus in CPP reinstatement rats induced by morphine

AIM: To investigate the role of excitatory amino acid transporter 3(EAAT3) in prefrontal cortex and hippocampus in morphine relapse by detecting the changes of EAAT3 expression in prefrontal cortex and hippocampus in conditioned place preference (CPP) reinstatement rat model induced by morphine.METHODS: Forty adult male SD rats, weighing 200-250 g, were randomly divided into 5 groups with 8 rats each: control group, CPP establishment group (Es), CPP extinction group (Ex), reinstatement 2 h group (Re2) and reinstatement 4 h group (Re4).Intraperitoneal (ip) injection of morphine was applied at a constant dose (10 mg/kg) for 10 days to the established CPP model.Normal saline instead of morphine was used to induce CPP extinction for 10 days.CPP was reinstated following a single priming injection of morphine (2.5 mg/kg).After the CPP behavior test, the rats were sacrificed, and the prefrontal cortex and hippocampus were collected for detecting the levels of EAAT3 by Western blotting.RESULTS: The accumulated time the rats spent in the drug-paired chamber was significantly longer in Es group, Re2 group and Re4 group than that in control group (P<0.05).Compared with control group, the expression of EAAT3 in prefrontal cortex significantly decreased both in Es group and Re4 group (P<0.05).No significant change of EAAT3 in hippocampus among groups was observed (P>0.05), while EAAT3 in hippocampal CA1 area significantly increased in Es group and Ex group as compared with control group (P<0.05).CONCLUSION: The expression of EAAT3 in prefrontal cortex decreases both in CPP establishment and reinstatement models, indicating that down-regulation of EAAT3 in prefrontal cortex may partly participate in the formation of opium relapse.     

Formation and activity of lymphocyte-derived microparticles

Lymphocyte-derived microparticles (LMPs) are small membrane vesicles that are released upon activation or during apoptosis from lymphocytes.The LMPs were detected at elevated levels in the patients with inflammatory diseases, cardiovascular diseases or diabetes. In addition, LMPs are important mediators of transferring biological information and switching on the biological effects through their interaction with the target cells. Moreover, LMPs play completely distinct roles in different physiological and pathological conditions. This article describes the possible mechanism involved in the formation, composition, key biological activities and the relationship with diseases.     

据小麦穗部特征建立判别品种对麦红吸浆虫抗性数学模型的研究

通过对小麦穗部形态特征逐步判断分析,建立了判别函数模型Ⅰ、Ⅱ,估计小麦品种对麦红吸浆虫的抗性.模型Ⅰ、Ⅱ的判对率分别为92.49%和92.14%.通径分析表明,小穗长度(x₁₀)和小穗宽度(X₁₁)是影响品种抗性的主要因素.     

陕西农业生产效率评价以及影响因素分析—基于DEA-Tobit两步法

运用DEA-Tobit两步法对陕西农业11个市区2002-2008年农业生产效率及其影响因素进行了分析,并结合Malquist指数,对陕西省农业生产效率的变化进行了动态评价。结果表明,全省平均综合技术效率较高,但是各市区之间差异较大。最后,通过Tobit分析发现,陕西农业生产效率与农民文化水平以及农业生产中投入资金量呈正相关关系。     

多孔介质物料热风干燥研究进展

多孔介质物料的热风干燥是许多工农业生产部门的重要生产工序,其干燥效能直接影响产品质量.多年来,国内外研究人员在多孔介质物料热风干燥领域进行了大量的研究工作,发展了多孔介质孔道网络模型,分析了分形多孔介质传热传质规律,建立了众多针对具体干燥对象的干燥模型,研制了多种多孔介质湿含量在线检测装置等.为此,从理论分析、数值模拟和实验研究3个层面综述了以上多孔介质物料热风干燥的研究进展,并对其发展趋势进行了展望.