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桔黄大牛角椒的果皮色遗传及雄性不育系的转育研究   总被引:1,自引:1,他引:0  
为选育黄果皮牛角新品种,利用本课题组转育成的牛角椒红果皮雄性不育系、红果皮保持系、美国大牛角高代自交系探讨生理成熟时牛角椒果皮颜色的遗传规律、牛角椒雄性不育性与果皮颜色的遗传规律。结果表明:牛角椒的果皮颜色的遗传,由1对等位基因控制,红色对黄色为显性遗传;牛角椒雄性不育性与果皮颜色的遗传属独立遗传。以此为依据提出了以黄果皮保持系材料为轮回亲本,转育黄果皮牛角椒雄性不育系的遗传模式,为转育黄果皮牛角椒新品种打下理论基础。  相似文献   
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以蝴蝶兰Phalaenopsis黄花系品种P.‘Taipei Gold’(2n=3x=57)作母本进行杂交育种有一个突出的问题是不育性障碍,为了克服这种障碍,多年来选择不同的父本进行杂交,终于发现采用P.‘Sara Gold’作父本进行杂交,收到蒴果1个,培育出杂交后代群体180株,其中有开花株99株。对杂交后代株高、冠幅、着花量、花径、花箭数、侧枝数及花色、唇瓣颜色和花瓣上的斑点进行观测记载。结果表明:杂交后代生长发育指标优于双亲的株数百分比:株高、冠幅、着花量、花径、侧枝数和花箭数分别占67.68%,86.87%,61.62%,24.24%,21.21%和26.26%;花瓣和唇瓣的颜色,基本遗传了双亲的特点,91%的后代花瓣颜色与双亲相似,74%的后代唇瓣颜色与双亲相似,90%的后代花瓣上出现了斑点。以P.‘Taipei Gold’作为母本成功杂交在国内首次报道,为蝴蝶兰黄花系杂交育种提供了实践依据。  相似文献   
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Several new multi-purpose non-rebreathing anaesthetic systems have been developed for human anaesthesia. This study evaluated a New Zealand designed non-rebreathing circuit, the Palmerston Valve, in anaesthetised spontaneously breathing dogs and compared it to the widely used Lack coaxial circuit. Arterial blood gas measurements 60 minutes after induction demonstrated comparable slight increases in PaCO2 in nearly all dogs maintained on the Palmerston Valve and Lack coaxial circuit with halothane and oxygen mixtures, and a fresh gas flow rate of 70 ml/kg/min.

Results suggest the Palmerston Valve is at least as efficient as the Lack coaxial circuit, while offering in the same unit the potential for economical controlled ventilation.  相似文献   
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研究了γ射线对棉铃虫当代及其F 1代繁殖的影响、辐照导致棉铃虫F 1代的染色体畸变和对F 1代雄虫有核精子束的影响。说明棉铃虫的辐照适期为蛹末期 ,辐射遗传不育 (F 1代不育 )的适宜剂量为 2 0 0Gy(剂量率为 3 2 3Gy min)  相似文献   
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Official eye examination records of 18 146 dogs in 17 breeds were analyzed in order to evaluate the Finnish Kennel Club's eye examination scheme. The most common inherited ocular diseases were the Collie eye anomaly (CEA) in the Rough Collie and the persistent hyperplastic tunica vasculosa lentis (PHTVL) in the Doberman. In both diseases the prevalence has also increased during the study period 1988–1997. The most likely reason for the increase is the change in examination routines that now makes it easier to find milder disease forms that were previously classified as normal. The prevalences of other inherited diseases are so low that no conclusions about the trends can be made. Also, the data have some defects that can cause biased estimations of prevalences. The costs of screening programs are very high and no direct economical benefits can be shown. Methods of improving the screening and effectiveness of the program are also presented.  相似文献   
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Multifocal retinopathy of Great Pyrenees dogs   总被引:1,自引:0,他引:1  
Forty-four related Great Pyrenees dogs were examined ophthalmoscopically. Focal retinal elevations, multiple gray-tan-pink subretinal patches, and discrete areas of tapetal hyper-reflectivity were seen in 19 dogs, ranging from 13 weeks to 10 years of age. These lesions varied in size from focal spots that were barely visible with the indirect ophthalmoscope to areas that were larger than the optic disc. Complete blood cell counts, serum biochemical profiles, urinalyses, and blood pressure measurements were completed on four affected dogs and all were within normal reference ranges. Photopic and scotopic electroretinography was completed and the a-wave and b-wave amplitudes and latencies were similar for affected and age-matched nonaffected Great Pyrenees and other normal dogs. Electroretinograms that were examined twice during a 3-year period on three affected adult dogs did not reveal significant progressive deterioration of the a or b-wave parameters. Fluorescein angiography was completed on four affected dogs of ages 1 (n = 2), 5, and 6 years. These angiograms were repeated in three of these dogs 1 year later. The blood ocular barrier was intact in these dogs but there was blocked choroidal fluorescence. Postmortem examination, light microscopy, scanning and transmission electron microscopy were performed on three affected puppies and two affected adult dogs. These examinations revealed that the lesions in the puppies were limited to bilateral multiple areas of retinal pigment epithelial vacuolation, hypertrophy, and apparent separation from Bruch's membrane, and multiple serous retinal detachments. The affected adult dogs had focal retinal degeneration and retinal pigment epithelial hypertrophy, hyperplasia and pigmentation. Pedigree analysis and test mating confirm that this condition is inherited, probably as an autosomal recessive trait. This condition develops at approximately 13 weeks of age and the focal areas of retinal detachment and retinal pigment epithelial vacuolation progress to permanent and stable focal areas of retinal degeneration, and retinal pigment epithelial hypertrophy and pigmentation.  相似文献   
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为分析桑树杂交后代桑叶品质性状的遗传特性,对种质创新和品种遗传改良提供材料、技术和理论支持,本研究以2个不同倍性桑树杂交亲本和组合后代群体为材料,通过对桑叶中水分、灰分、可溶性糖、粗蛋白、粗纤维、多酚类物质、黄酮类物质含量及体外总抗氧化能力等指标的测定,研究了桑叶品质性状的遗传倾向。研究结果表明:2个组合所有杂交后代不同性状遗传差异较大,其中桑叶中水分和灰分含量2个性状变异系数小于10%,遗传相对稳定,而可溶性糖、粗蛋白、粗纤维、多酚类、黄酮类物质含量及体外总抗氧化能力、清除.OH能力等变异系数较大,遗传多样性丰富,在群体中选择特异性状单株具有很大潜力。2个杂交组合后代群体中桑叶营养物质(水分、灰分、可溶性糖、粗蛋白和粗纤维)含量均值均小于相应亲本均值;活性物质(多酚类、黄酮类)含量及体外抗氧化能力(总抗氧化能力、清除.OH能力)均值均高于相应亲本均值,对杂交后代进行优良单株筛选可获得较高的遗传增益。综合分析杂交后代桑叶品质性状的遗传特性,可为桑树种质创新和品种遗传改良提供材料、技术和理论支持。  相似文献   
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