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961.
962.
963.
研究优质蛋白玉米籽粒品质性状组间典型相关性结果表明,2个半硬质胚乳奥帕克-2玉米群体(“中群14QPMC3”和“陕综5号QPMC0”)籽粒物理性状中硬质度、籽粒密度、百粒重与胚比、百粒体积呈负相关效应,营养品质中赖氨酸含量、蛋白质品质性状为其核心,籽粒密度(或硬质度)可作为蛋白质品质的间接选择指标;籽粒物理性状、蛋白质品质性状在赖氨酸产量构成中起决定性作用,全籽粒蛋白质品质与胚乳蛋白质品质紧密相关,而与胚蛋白质品质无关,高赖氨酸高油分育种相统一。 相似文献
964.
965.
玛曲高寒沙化草地植物生态位特征研究 总被引:7,自引:0,他引:7
研究高寒沙化草地植物群落特征和演替状况,对恢复生态环境、提高草地生产力具有重要意义。本文采用样方法对玛曲高寒沙化草地20个样地的植物种群进行系统调查,并计算其主要植物的重要值、生态位宽度和生态位重叠值。结果表明:该草地当前的优势种为异针茅(Stipa aliena);生态位宽度最大的是亚优势种高山唐松草(Thalictrum alpinum)和乳浆大戟(Euphorbia esula),为0.974,而优势种异针茅仅0.941,说明优势种并不具有最强适应能力和竞争力,在群落中的地位也不稳定;生态位宽度大的物种之间具有大的生态位重叠值,其中高山唐松草和乳浆大戟生态位重叠值最大,达0.987,与其他种群之间的竞争也较强,表明高寒沙化草地的演替方向将是杂类草取代禾草的优势地位,如不及时治理,草地将进一步退化。 相似文献
966.
To observe the antiviral action of 16 kinds of Chinese medicinal herbs (Houttuynia cordata Thunb,Flos Chrysanthemi,Flos Lonicerae Confusae,Anemarrhena asphodeloides,CassiaTwig,Herba Ephedrae,Radix Paeoniae Rubra,Bupleurum chinense,Dryopteris setosa,Folium Isatidis, Gardenia jasminoides Ellis,Mntha haplocalyx Briq,Paeonia suffruticosa Andr,Cornu Bubali, Herba Senecionis Scandentis,Radix Gentianae) against porcine reproductive and respiratory syndrome virus (PRRSV), the blocking, inhibiting and killing roles were detected in present study in vitro. The results showed that 13 kinds of Chinese medicinal herbs had antiviral actions against PPRSV except Paeonia suffruticosa Andr, Herba Senecionis Scandentis and Folium Isatidis, and Houttuynia cordata Thunb, Flos Chrysanthemi, Anemarrhena asphodeloides, CassiaTwig and Radix Paeoniae Rubra exhibited the best antiviral actions followed by Herba Ephedrae, Bupleurum chinense and Dryopteris setosa. 相似文献
967.
We tried to identify the bacteria and explore the mechanism of the bacteria's pathogenicity via housekeeping gene gyrB and in vitro organ culture (IVOC) of ileum and intramuscular injection. Microscope, electron microscope and scanning electron microscope were also used to observe and the structure, pathogen of M12 and changes of infected tissues. The results showed that M12 was short gram-negative bacteria, and both ends of it were obtuse and the size without flagellum was (0.6 to 1.6) μm×(0.6 to 0.7)μm while length of flagellum was about 2 to 3 times of the length of bacteria.It had 100.0% similarity with Aeromonas caviae from GenBank. IVOC test observed M12' adhesion in intestinal epithelial cell, resulting in formulation of biofilm structure and damage in intestinal epithelial cell. Histopathologic examination showed that M12 could cause damage in intestine, liver, lung, kidney, muscle tissue of rabbit.The assay would offer references for researching the pathogenic mechanism of Aeromonas caviae. 相似文献
968.
Association between in-transit loss, internal trailer temperature, and distance traveled by Ontario market hogs 下载免费PDF全文
Charles Haley Catherine E. Dewey Tina Widowski Robert Friendship 《Canadian journal of veterinary research》2008,72(5):385-389
An observational study was conducted from July to October 2004 to determine the association between in-transit losses of swine and internal trailer temperature after controlling for loading density, trip distance, herd size, and random trip effect. A convenience sample of 3 trucking companies was used to collect temperature, relative humidity, and global positioning data for 104 trips that delivered 21 834 pigs from 371 producers to Ontario abattoirs. The association between in-transit loss and trailer temperature was determined using the 90th percentiles of internal temperature for each trip. Average loading density was 0.36 m2/100 kg pig (range 0.28 to 0.50 m2/100 kg pig). Average in-transit loss was 0.12%; however, 94% of producers experienced no losses. As the 90th percentile of internal trailer temperature increased from a range of 8.6°C to 23.3°C to a range of 23.4°C to 26.1°C, average in-transit loss ratio increased approximately 3-fold, with an additional 2-fold increase as the range increased from 26.2°C to 28.9°C to 29.0°C to 30.5°C. As the 90th percentile of temperature increased by 1°C over the full range of temperatures in this study, in-transit loss was expected to increase 1.26 times. The in-transit loss was expected to decrease 0.81 times for each 50-km increase in distance traveled between the farm and the abattoir. 相似文献
969.
970.
羊痘病毒分子特征及检测方法研究进展 总被引:2,自引:0,他引:2
羊痘是以发热、全身性的皮肤损伤、痘疹和淋巴结病变为特征的一种传染性高、病死率高、分布广泛的烈性羊病毒病,是所有动物痘病毒中最为重要的一种,严重影响养羊业和国际贸易的发展。目前,国内外对羊痘的研究主要涉及病原学、诊断技术和基因工程疫苗等方面。 相似文献