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1.
Summary. Tracer studies using single drops of solutions containing 3–amino-1,2,4–triazole-5–14 C (aminotriazole-14 C) or 2,2–dichloropropionic acid-2–14 C (datapon-14 C) revealed that in couch plants (Agropyron repens (L.) Beauv.) growing under field conditions in the autumn and at the stage where the aerial shoots were 40–50 cm long, both compounds moved in both symplast and apoplast. Dalapon was less mobile in the symplast than aminotriazole and only negligible amounts of dalapon were translocated to the rhizomes. The nodes of the treated shoots appeared to act as barriers to translocation, a phenomenon more pronounced for dalapon than for aminotriazole.
Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully-expanded leaf.
In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots. 相似文献
Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully-expanded leaf.
In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots. 相似文献
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Considering the difficult of acquiring and transmission the signal from the moving equipment, a new fault diagnosis monitoring system is presented. The system acquires the state signal from the moving equipment by data acquisition module that based in W77E58 high-speed SCM, and transmits the data fast by wireless mode. The signal data can be use for fault diagnosis and precise analysis. The system has the ability for acquiring abundance of data with a high speed, the ability for high accuracy data conversion, and has a function of programme controlling gain and programme controlling low-pass filtering. The successful application of this system on the vibration monitor about the material-transporting bogie in an iron works of a domestic steel enterprise proves the stability and credibility about the design project, also testifies its practical value and versatility. 相似文献
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Recently,distributed intelligent systems based on multi-agent have been applied to many fields successfully.the multi-agent technique is introduced into the rotating machinery fault diagnosis system.With the combination of CBR technique,Basalstructure and development approach of the system are analyzed,and better cooperation among agents is realized.As a result,the system overcomes the limitation of single fault diagnosis method,and solves the contradictionbetween versatilityand adaptabilityof diagnosis software.Furthermore,a reference can be used for the research and development of multi-algorithmdiagnosis system of rotating machinery.The application in a factory's Networked Online Monitoring and Fault Diagnosis System for Turbine Fan shows that the system can diagnosefault rapidly and exactly. 相似文献
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地震干扰后恢复群落物种组成与生物量分配特征 总被引:2,自引:0,他引:2
在对四川王朗自然保护区地震干扰后恢复群落(群落E)大量调查的基础上,通过收获法研究了群落E草本层的物种组成和生物量分配特征,并与未受干扰的原始林群落(群落F)相比较,结果表明:群落E中科、属、种丰富度、草本层总生物量均显著低于群落F。群落E地上生物量、地下生物量、草本及灌木物种生物量也均显著低于群落F,并且2种群落生物量均主要分布于地上及草本植物;群落E生物量主要分布于针刺悬钩子(Rubus pungens)、掌裂蟹甲草(Cacalia palmatisec-ta)和宽翅香青(Anaphalis latialata)3个物种,而群落F生物量主要分布于短尾铁线莲(Clematisbrevicaudata)、针刺悬钩子和长果升麻(Souliea vaginata)3个物种。研究表明,土壤是地震干扰后群落恢复速度及生物量大小的主要限制因子。 相似文献
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珍珠鸡与家鸡的动物学分类地位相差甚远,1日龄珍珠鸡无法通过翻肛鉴别性别,直接影响其管理和生产流程。为解决珍珠鸡早期性别鉴定的问题,分析了珍珠鸡快、慢羽遗传特征以及利用快慢羽建立自别雌雄配套系的可能性,同时尝试利用CHD-1基因对珍珠鸡实施早期性别鉴定。通过肉眼观察1日龄珍珠鸡羽速,并采集其毛囊组织,检测珍珠鸡快慢羽ev21基因插入位点;以家鸡CHD-1基因序列为参考,扩增检测珍珠鸡的毛囊DNA,鉴定珍珠鸡的性别。未检测出该群体存在慢羽个体;另外,性别鉴定结果与阳性对照家鸡的条带一致,公母间出现差异,且与180日龄珍珠鸡性成熟时的翻肛鉴定结果一致。控制珍珠鸡快慢羽性状的遗传基础与家鸡可能存在差异,该群体目前不能通过系统选育建立快慢羽自别雌雄品系,而CHD-1基因可用于珍珠鸡早期性别鉴定,表明该基因在家鸡与珍珠鸡间遗传特征相同。在珍珠鸡快慢羽自别雌雄品系尚未建立前,可用于珍珠鸡早期性别鉴定。 相似文献
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1日龄非免疫鸡分别人工感染马立克氏病病毒(MDV)I型国际标准强毒GA株、I型MDV疫苗毒CVI988株后,从第5日起,定期采血,用本实验室改进的Trap法和Bandscan软件测定、分析并计算感染过程中其外周血液单核细胞(PBMC)的端粒酶活性变化;同时用抗MDV囊膜糖蛋白B(gB)单克隆抗体介导的间接免疫荧光试验检测MDV在外周血液单核细胞中的感染状况。结果表明,自接种I型强毒GA株后,端粒酶在没有临床症状和可视病变出现之前就可检测到,并且随着MDV感染后日龄的增加逐渐升高,在25日龄时其相对活力达到最高值;而接种CVI988后,整个生长过程端粒酶活性均呈阴性。从感染第5日到鸡发病死亡前,都能检出GA株引起的病毒血症,并于18~22 d左右达到高峰;而接种CVI988株后第5日到第20日止,能检出病毒血症,并于第10~12天左右达到高峰。 相似文献
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