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101.
光周期对不同秋眠型苜蓿光敏色素和内源激素的影响简 总被引:1,自引:0,他引:1
本试验研究了不同光周期对3种秋眠型苜蓿光敏色素和植物体内源激素含量的影响,为揭示苜蓿秋眠性的调控机理提供科学依据。试验采用FQ-PCRSYBR-GreenI方法,在人工气候室,以美国苜蓿秋眠级标准对照品种Norseman(FD1,秋眠型苜蓿,秋眠1级)、Dupuils(FD5,半秋眠型苜蓿,秋眠5级)和CUF101(FD9,非秋眠型苜蓿,秋眠9级)为材料,设计4个不同的日照长度梯度(7,10,13和16h/d),对其植株处理35d,测定叶片中光敏色素(PHYA 、PHYB)mRNA 表达量,采用(ELISA)试剂盒法测定内源激素生长素(IAA)、脱落酸(ABA)、玉米素核苷(ZR)、赤霉酸(GA3)的含量。结果表明,3种不同秋眠型紫花苜蓿PHYA 和PHYB 在短日照条件下合成量大,其中以Norseman表现最为明显。不同秋眠类型苜蓿叶片中的GA3/ABA、ZR/ABA和IAA/ABA均随着光照时间延长而增大;短日照条件下3种秋眠型苜蓿ABA的合成量均为最大,GA3的含量最低,生长严重受到抑制。可能PHYA 和PHYB 直接或间接影响了内源激素GA3、ZR、IAA、ABA合成量,进而调控了苜蓿的秋眠。 相似文献
102.
猪多杀性巴氏杆菌环介导等温扩增检测方法的建立 总被引:1,自引:0,他引:1
为建立猪多杀性巴氏杆菌(Pm)的快速检测方法,本研究以Pm的PlpB基因序列为靶基因设计特异性引物,建立了Pm特异性的环介导等温扩增(LAMP)快速检测方法.经反应条件优化,确定反应条件为63℃,20 min.检测结果显示,建立的LAMP检测方法具有良好的特异性,灵敏度为25 cfu/mL;与大肠杆菌、副猪嗜血杆菌、胸膜肺炎放线杆菌、沙门氏菌无任何交叉反应.采用建立的LAMP方法与常规PCR方法对临床54份分离样品进行检测,检测结果为31份为阳性,23份为阴性,二者符合率为100%.该方法的建立为Pm在临床上的快速检测提供了一种新的技术手段. 相似文献
103.
采用技术经济分析方法中的动态分析、盈亏平衡分析、单因素敏感性分析等方法,研究了良种油茶Camellia oleifera栽植从第1年开始到第30年为一个经济生产时段的生产成本构成,主要动态经济指标(净现值、内部收益率、投资回收期),设计产量和价格收益率的盈亏平衡点,以及销售收入和生产成本等不确定因素对净现值的影响。结果表明:在30 a的生产时段中,按7%基准贴现率和2010-2012年茶油市场平均价格60.00元·kg-1计算,累计净现值为4.38万元·hm-2,内部收益率为12.05%;投资回收期为16.41 a;当整个生产时段的销售收入减少19.50%或生产成本增加24.20%时,发展良种油茶生产将变得不可接受,但从目前市场和生产实际情况分析,出现这种情况的可能性很小。政府在油茶产业资金扶持政策上,除现有的造林补贴政策外,还可通过扩大小额贷款范围、延迟还贷时间;采用补助政策,加快经济适用的小型农机具(如油茶采果机、山地土壤耕作机等)的开发、推广应用,鼓励油茶加工企业采用先进技术改造现有榨油机械,提高茶油加工效率和效益等方法,促进油茶产业的发展。 相似文献
104.
KANG Jing-jing ZHAO De-ming TENG Ke-dao JIAO Xi-lan WANG Ping-li SUN Zhe NI Pei-pei WANG Zhi-feng ZHANG Rui YANG Yu-rong LIANG Hong-de 《农业科学学报》2014,13(4):858-869
Ulcerative colitis (UC) is a lifelong illness with profound emotional and social impacts, and could cause serious damage to large intestine, especially in colon. However, the pathogenesis of UC remained unclear. The present study attempts to find out the role of matrix metalloproteinases-7 (MMP-7) and lysozyme in the pathogenesis of UC through a mice model induced by dextran sulfate sodium (DSS). The UC model was evaluated both by disease activity index (DAI) and the intestinal histopathology. The results show that there is a high correlation between the DAI score and the pathological changes of colon. Interleukin-6 (IL-6) serum levels and large intestinal fluids levels in UC mice are always higher than that of the control groups, which might be associated with the degree of the inflammation damage in the colon. The change tendency of the MMP-7 mRNA and protein expressions are both up-regulated firstly and then down-regulated from 1 to 5 d in the colon, but only the MMP-7 protein is up-regulated at 7 d again. The up-regulated MMP-7 levels in the early stage of UC may play a protective role through the activated defensins, while the down-regulated levels in the mid-later stage of UC may be connected with the severe lesions in the colon. However, the up-regulated MMP-7 levels in the later stage of UC in the colon may also contribute to the tissue repair or be served as a marker to CRC (colorectal cancer). The distribution of lysozyme protein indicates that there may be Paneth-like cells in the colon. Both the changes of MMP-7 and lysozyme in the small intestine may play a protective role for the safe environment of the whole gut, especially to the colon of UC. 相似文献
105.
ZHUANG Xiang-hua NI Yi-hong LIU Yuan-tao SUN Ai-li SUN Fu-dun JIANG Dong-qing LI Xiao-bo CHEN Shi-hong 《园艺学报》2014,30(11):2084-2088
AIM: To establish a suitable chronic intermittent hypoxia (CIH) model in rats for modeling the obstructive sleep apnea-hypopnea syndrome (OSAHS) and further to explore the relationship between vaspin and insulin signaling pathways at mRNA and protein levels. METHODS: Healthy male Wistar rats were divided into control group and CIH group. The rats in control group were raised under physiological condition, and the rats in CIH group were kept in the plexiglass chamber between 9:00~17:00 and underwent intermittent hypoxic challenge 8 h/d for 8 weeks. The blood pressure of arteria caudilis in the rats was measured by tail cannulation before and after study. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), fasting insulin (FINS), vaspin and adiponectin levels were measured. The mRNA expression of vaspin was detected by real-time PCR. The protein levels of vaspin, Akt and p-Akt were determined by Western blotting.RESULTS: Before the experiment, the weight and blood pressure of the rats had no significant difference, while after the experiment the blood pressure in CIH group was obviously higher than that in control group. FPG, FINS, TG and TC in CIH group were also markedly higher than those in control group (P<0.05). Serum vaspin concentration was significantly correlated with FPG, FINS, HOMA-IR and TC. The expression of vaspin at mRNA and protein levels in the fat tissue of CIH group was evidently higher than that in control group. The protein levels of p-Akt decreased distinctly in CIH group. CONCLUSION: The levels of FINS, HOMA-IR, SaO2 and vaspin were markedly higher than those in control group, indicating that there was a close relationship between vaspin and insulin resistance in OSAHS. 相似文献
106.
107.
风险评估是对转基因鱼环境释放依法管理的一项重要内容,也是转基因鱼安全研究的核心内容之一。文章在分析和比较国内外有关转基因生物风险评估方法的基础上,对转基因鱼环境释放风险评估的基本原则和一般模式进行了全面的描述。 相似文献
108.
109.
针对茶园土壤板结较为严重、行距小、耕作阻力大且易使耕作机构发生缠绕等问题,提出了一种基于离散元法的仿生铲,并对其进行减阻性能研究。使用离散元仿真与试验结合的方法对茶园板结土壤的物理参数进行测量。以鼹鼠爪趾为原型,结合其挖掘动作,设计出基于四杆机构的耕作机构,并使用离散元的方法研究鼹鼠爪趾的趾尖、趾廓及两者复合的仿生特征的减阻效果。离散元仿真结果表明,在各个耕作条件下,趾尖仿生特征的平均扭矩减小比例和功耗减少比例分别为1.72%~5.04%和1.58%~4.84%,趾廓仿生特征的平均扭矩减小比例和功耗减少比例分别为34.06%~39.29%和29.02%~34.73%,复合仿生特征的平均扭矩减小比例和功耗减少比例分别为36.61%~42.06%和30.84%~38.15%,说明趾尖和趾廓两个仿生特征的减阻效果在一定程度上可以叠加,复合后的仿生特征有更好的减阻效果。 相似文献
110.
Zhenguo YANG Daoyan XIE Aisi DA Xiujun JIANG Jing NI Ping HUANG Jianping CHAI 《农业科学与技术》2014,15(12):2159-2163
[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal ratio of both acaricides were determined by means of co-toxicity factors and co-toxicity coefficients(CTC).[Result]At 24 h post-treatment,the LC50values of diafenthiuron and fenbutatin-oxide against T.cinnabarinus female adults were 154.67 and 93.26 mg/L,respectively,and the synergistic mass ratios of diafenthiuron and fenbutatin-oxide ranged from 1:0.06 to 1:0.87,and the optimal diafenthiuron-to-fenbutatin-oxide ratio was 1:0.39 with the LC50and CTC of 67.87 mg/L and 188.93(CTC significantly above 100 strongly indicated synergism),respectively,and the toxicity relative to diafenthiuron and fenbutatin-oxide was 2.28 and 1.37 times,respectively.[Conclusion]The joint acaricidal action of diafenthiuron and fenbutatin-oxide strongly indicates synergism.These findings proved scientific theoretical basis for mixing diafenthiuron and fenbutatin-oxide to control spider mites and developing a new synergisic acaricide. 相似文献