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11.
甘蔗线虫病抗性基因的PCR检测研究 总被引:3,自引:0,他引:3
以38份未经线虫病常规鉴定的甘蔗种质资源为供试材料,根据番茄抗根结线虫病基因和甜菜抗胞囊线虫病基因的保守序列区域,分别设计了2条上游引物、2条下游引物,对设计的引物进行组合后,应用PCR特异扩增从中分别筛选出各1对特异引物。用抗根结线虫基因设计的特异引物进行扩增最终获得了1条大约460 bp大小的特异片段;用抗胞囊线虫基因设计的特异引物进行扩增最终获得了1条大约690 bp大小的特异片段,进一步进行了PCR-Southern杂交,确认了该2条特异引物的真实性。 相似文献
12.
13.
一 饲料企业统计技术应用过程存在的问题
目前企业在统计技术应用过程中易出现的问题表现在以下几点。
1 数据来源失真
(1)未能如实反映客观情况,有的原始统计记录收集不足。 相似文献
14.
为了客观评价硫酸新霉素可溶性粉对靶动物猪临床应用的安全性,将32头仔猪随机分为4组,每组8头,分别设1倍、3倍、5倍临床推荐剂量组和空白对照组,连续混饮硫酸新霉素可溶性粉15 d,通过检测各组受试猪的临床表现、血液常规指标、血清生化指标、尿液常规指标及病理学变化等评价其临床用药的安全性。结果:硫酸新霉素可溶性粉以5倍临床推荐剂量内应用于靶动物猪后,对其临床症状、体重、血常规、血生化及尿常规等指标没有显著影响,解剖学及病理组织学检查也未见任何病理变化,说明硫酸新霉素可溶性粉以1倍、3倍、5倍临床推荐剂量应用于靶动物猪是安全的。 相似文献
15.
饲料中添加酶制剂的作用 总被引:3,自引:0,他引:3
随着酶制剂的开发和利用,人们对不同种类的动物,不同的日粮类型作了大量的研究。结果发现饲料中添加酶制剂,除分解特定的底物外,还可最大限度地消除饲料中某些抗营养因子的抗营养作用,影响动物机体的内泌,增强免疫,改善动物生产性能,提高畜产品的产量和质量。 相似文献
16.
低温胁迫对草地早熟禾抗性生理生化指标的影响 总被引:32,自引:2,他引:32
研究低温胁迫对草地早熟禾生理生化指标的影响。结果表明,在5℃下,超氧化物岐化酶(SOD)和过氧化氢酶(CAT)的活性随着胁迫时间的延长而增加,当4h时出现最大值,之后活性逐渐下降。当温度为0℃与-6℃时,两种酶的活性随着胁迫时间的延长而急剧下降,接近于零,温度越低,下降越快。叶绿素和类胡萝卜素含量随着肋迫时间的延长而下降,温度越低下降越快。5℃对脯氨酸含量无明显影响,在0℃与-6℃时,随着时间的延长,含量则明显增加。5℃和0℃低温胁迫对质膜相对透性无明显影响,-6℃时,质膜相对透性明显增大。供试指标对低温胁迫敏感性的顺序是:超氧化物岐化酶、过氧化氢酶>类胡萝卜素>脯氨酸>叶绿素>质膜相对透性。 相似文献
17.
Clark L Clutton RE Blissitt KJ Chase-Topping ME 《Veterinary anaesthesia and analgesia》2008,35(1):22-29
OBJECTIVE: To investigate the effects of peri-operative morphine on the quality and duration of recovery from halothane anaesthesia in horses. STUDY DESIGN: Prospective randomized study. ANIMALS: Twenty-two client owned horses, ASA category I or II. METHODS: Horses undergoing elective surgical procedures were divided into two groups and paired according to procedure, body position during surgery, body mass and breed. Group M+ received morphine by intravenous injection (0.15 mg kg(-1)) before induction of anaesthesia and then by infusion (0.1 mg kg(-1) hour(-1)) during anaesthesia. Group M- received the same anaesthetic agents except that morphine was excluded. At the end of surgery, the horses were placed in a recovery box and allowed to recover without assistance. Recoveries were recorded on videotape, beginning when the anaesthetist left the recovery box, and ending when the horse stood up. Recoveries were assessed from digital video recordings by three observers, unaware of treatment. The time to first movement, attempting and attaining sternal recumbency and standing were recorded. The quality of various aspects of the recovery was assessed to produce a total recovery score; high numerical values indicate poor recoveries. The duration of anaesthesia and the total dose of morphine administered were recorded. RESULTS: The mean morphine dose (95% CI) was 147 (135-160) mg [equivalent to 0.27 (0.25-0.29) mg kg(-1)]. The recovery scores (median, 95% CI) for the M- and M+ groups were 25, 19-41 and 20, 14-26, respectively. Total score increased as duration of anaesthesia increased, independent of treatment. Untreated (M-) horses made more attempts to achieve sternal recumbency: mean number of attempts (95% CI) for M- was 4.5 (2.7-6.2) compared with 2.0 (1.4-2.6) (M+). Untreated horses made more attempts to stand (2.1, 1.6-2.6) compared with the morphine recipients (1.3, 1.1-1.5). Time to standing (in minutes) was significantly (p = 0.0146) longer for the untreated (31.3, 24.3-38.3) compared with treated animals (26.6, 20.9-32.3). The interval between the first movement in recovery to the time at standing was significantly (p < 0.001) longer for M- (14.5, 12.1-16.9 minutes) compared with M+ animals (7.4, 5.0-9.8 minutes). CONCLUSIONS AND CLINICAL RELEVANCE: Recoveries from anaesthesia in the morphine recipients were characterized by fewer attempts to attain sternal recumbency and standing, and a shorter time from the first recovery movement to the time of standing. 相似文献
18.
The study was aimed to explore the antioxident function of sulforaphane (SFN) on the leydig cells of cadmium (Cd) exposured mice.Cd and SFN were added to the cell culture medium of TM3 cell, half inhibitory concentration (IC50) of Cd and SFN safe dose range were determined.The tested model was set up,and the relative survival rate of TM3 cells, lactate dehydrogenase (LDH) activity and cell antioxidant levels were determined to study the antioxident function of SFN to cadmium exposured mice.The results showed that:①With the increase of Cd concentration,the relative survival rate of TM3 cells was decreased,and the IC50 of Cd was 51.4 μmol/L;Within a certain concentration range,SFN could increased the cells survive rate,but there was toxicity when the SFN concentration was more than the scope,and the greater the concentration,the greater the toxicity. At experimental condition,SFN safety concentration were 2.5,5 and 10 μmol/L.②Compared with the control group,the GSH content,the T-SOD and GSH-Px activities in Cd group were significantly or extremely significantly decreased (P < 0.05;P < 0.01),and the LDH activity,the MDA content were increased.Additionally,the LDH activity and MDA content of SFN groups were decreased,while others three indexes were increased. Compared with Cd group,the GSH content,the T-SOD and GSH-Px activities of Cd+SFN groups were significantly or extremely significantly increased (P < 0.05;P < 0.01),however,the LDH activity,MDA content were decreased. The result indicated that SFN had the antagonism effect on toxicity of Cd in TM3 cell. 相似文献
19.
对东北虎种群的科学监测是采取有效保护、管理及恢复措施的基础,而准确的个体识别又是保证有效监测的前提。尤其是在中国,在野生东北虎种群数量很少,种群密度极低的情况下,能根据它留下的各种信息进行个体识别就显得尤为重要。目前,用于野生东北虎个体识别的技术主要有:足迹识别、DNA识别、条纹识别以及气味识别等。本文对这几种技术的特点、研究进展、应用注意事项等做了介绍,并且结合中国的实际情况,分析每种技术在中国的适用性,认为如果要建立中国的东北虎种群数量数据库,足迹识别和DNA识别比较适合在中国现有东北虎分布区推广使用。通过足迹识别,信息容易获取,也是最经济和比较成熟的方法;由于种群密度低,含DNA的遗传样本虽不能每次都采集到,但可以长期积累;现阶段条纹和气味识别只能起到辅助的作用。 相似文献
20.
为研究内生真菌对醉马草白粉病抗性的影响,在温室条件下,对自然发生不同程度白粉病(健康、轻度感病和重度感病植株)的带内生真菌(E+)和不带内生真菌(E-)的醉马草植株的发病率、病叶率、病情指数及各项生理生化指标进行测定。结果表明,E+醉马草的发病率48%显著低于E-醉马草的发病率97%(P0.05),E+的病叶率60%显著低于E-醉马草病叶率86%(P0.05),E+醉马草的病情指数为50.76,E-醉马草的病情指数为82.49;通过各项生理生化指标的测定发现与健康植株相比,在轻度和重度发病植株中,内生真菌的存在可以显著(P0.05)提高醉马草叶片的叶绿素含量和脯氨酸含量,E+醉马草的SOD酶活性和POD酶活性也显著高于E-醉马草,同时内生真菌显著地降低了醉马草叶片中丙二醛(MDA)的含量。据此说明内生真菌的存在能够提高醉马草抗白粉病的能力。 相似文献