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991.
解放钟和早钟6号枇杷果实的贮藏性与采后生理变化比较 总被引:3,自引:1,他引:2
较研究解放钟与早钟6号枇杷果实在20℃贮藏条件下果实的贮藏性及采后生理变化规律.结果表明,解放钟枇杷果实比早钟6号枇杷果实较耐贮藏,耐贮藏的解放钟枇杷果实贮藏期间果实失水率较低,保水能力较强.贮藏期间,枇杷果实的总酸含量快速下降,但解放钟枇杷果实能保持较高的总酸含量,而且极显著高于早钟6号枇杷果实;可溶性糖和还原糖含量在贮藏前期(0~5 d)略有上升而后缓慢下降;超氧歧化酶(SOD)和过氧化氢酶(CAT)活性表现为先升后降的趋势,而且有酶活力峰出现,与解放钟枇杷果实相比,早钟6号枇杷果实SOD和CAT活性变化幅度大、酶活力峰提早出现,代谢不稳定;早钟6号枇杷果实H2O2和MDA含量均比解放钟枇杷果实高,表明早钟6号枇杷果实活性氧代谢加强,从而加快果实衰老,缩短果实保鲜期. 相似文献
992.
将M3、ASI方法测试土样数据与常规方法测试的数据比较,得出其相关性。其中:磷R(旱田)=0.938779,R(水田)=0.905098;钾R(旱田)=0.865785,R(水田)=0.928413。按照公式将M3方法测试的磷钾数据转换成常规方法数据,并以常规方法评价指标为依据,解决了磷钾数据应用问题。氮的数据经比较没有相关性,可对照土壤有机质、速效氮的分级指标与氮素推荐量,根据目标产量和农户实际用肥量,提出氮的推荐量。 相似文献
993.
基于生化数据处理模型的测控软件开发策略 总被引:2,自引:0,他引:2
为改变国产生化分析仪器测控软件功能单一的落后状况,针对非生化检测专业的软件开发人员提出了一种基于生化数据处理模型的测控软件开发策略。详细地分析了软件总体结构、测试机理和数据库操作方面的策略内容,对于生化数据的处理和分析提出了三种数据处理模型,并设计了其中一种程序流程。 相似文献
994.
WU Jian-li SHI Yong-feng CHEN Jie Casiana Vera CRUZ ZHUANG Jie-yun Hei LEUNG ZHENG Kang-le 《水稻科学》2007,14(1):21-26
The phenotypically uniform indica variety IR64 was chosen for study of the source and inheritance of within cultivar residual variation using a set of SSR markers.Residual heterogeneity in IR64 was identified on the short arm of chromosome 2 involving at least 5 SSR loci spanning nearly 30 cM.The SSR variations originated from the parental lines of IR64(IR5657-33-2/IR2061-465-1-5-5)and were segregating in the selfed bulk seed stock in a Mendelian manner for more than 20 years.This study verified that the within cultivar variations of SSR in a morphologically uniform variety IR64 of a selfing crop came from its parental lines,which has immediate and commercial applications including test of hybrid seed purity,varietal fingerprinting,and curation and propagation of germplasm collections. 相似文献
995.
离体早熟梨芽休眠进程的影响因素研究 总被引:1,自引:1,他引:0
以早熟梨离体结果枝为试验材料,通过控制温度、光照条件以及喷施不同种类和浓度的生长调节剂生长调节物质来研究影响早熟梨芽休眠进程的因素。试验结果发现在25℃条件下在0.04%、0.08%的乙烯利和0.1mg/L和0.3ABA mg/L都能在一定时间内抑制萌芽,0.3mg/L IAA处理能促进萌芽,而0.6mg/L IAA和 GA3处理效果不明显;而在15℃条件,所有处理的萌芽率都为0;试验结果还表明在1500lx光照强度下光照时间对早熟梨芽休眠的影响效果不显著。 相似文献
996.
Differences in cultivar response and complete sequence analysis of two isolates of wheat yellow mosaic bymovirus in China 总被引:1,自引:0,他引:1
J. Chen J.-P. Chen † J.-P. Yang Y. Cheng A. Diao M. J. Adams J. Du 《Plant pathology》2000,49(3):370-374
Seeds of selected European and Japanese winter wheat cultivars were grown at two experimental sites in China, namely Yaan, Sichuan province (YA), and Yangzhou, Jiangsu province (YZ), where wheat yellow mosaic bymovirus (WYMV) was severe. There were some differential responses of the cultivars to the virus isolates present at the two sites. The complete nucleotide sequence of both RNAs of both virus isolates was determined. Their genome organization was identical to that reported for a Japanese isolate and the sizes were very similar. Nucleotide comparisons demonstrated that parts of the CI and NIa coding regions on RNA1 and the N-terminal part of the P2 coding region on RNA2 were particularly variable, while substantially conserved regions occurred in the 3' UTR of RNA2, the 7K, one part of the CI and parts of the NIb and coat protein. It seems unlikely that differences in the 7K and NIa-VPg proteins are responsible for virulence differences and the CI and NIb regions were considered the most promising for further study. 相似文献
997.
Experiments in controlled environments were carried out to determine the effects of temperature and leaf wetness duration on infection of oilseed rape leaves by conidia of the light leaf spot pathogen, Pyrenopeziza brassicae . Visible spore pustules developed on leaves of cv. Bristol inoculated with P. brassicae conidia at temperatures from 4 to 20°C, but not at 24°C; spore pustules developed when the leaf wetness duration after inoculation was longer than or equal to approximately 6 h at 12–20°C, 10 h at 8°C, 16 h at 6°C or 24 h at 4°C. On leaves of cvs. Capricorn or Cobra, light leaf spot symptoms developed at 8 and 16°C when the leaf wetness duration after inoculation was greater than 3 or 24 h, respectively. The latent period (the time period from inoculation to first spore pustules) of P. brassicae on cv. Bristol was, on average, approximately 10 days at 16°C when leaf wetness duration was 24 h, and increased to approximately 12 days as temperature increased to 20°C and to 26 days as temperature decreased to 4°C. At 8°C, an increase in leaf wetness duration from 10 to 72 h decreased the latent period from approximately 25 to 16 days; at 6°C, an increase in leaf wetness duration from 16 to 72 h decreased the latent period from approximately 23 to 17 days. The numbers of conidia produced were greatest at 12–16°C, and decreased as temperature decreased to 8°C or increased to 20°C. At temperatures from 8 to 20°C, an increase in leaf wetness duration from 6 to 24 h increased the production of conidia. There were linear relationships between the number of conidia produced on a leaf and the proportion of the leaf area covered by 'lesions' (both log10 -transformed) at different temperatures. 相似文献
998.
为探讨适合四川省实际的种猪测定饲料配方及适宜的饲喂方式,本试验采用了两因子重复设计,即三种不同营养浓度的饲料、自由采食和定量给食两种饲喂方式,对48头杜长仔猪进行试验,测定猪在30~100千克体重阶段的日增重和耗料指数,并观察不同钙、磷水平对猪四肢的影响.试验结果表明三种不同营养浓度的饲料和饲喂方式对猪日增重和耗料指数均无显著影响,但营养浓度略低的饲料成本较低.为便于管理,采食方式建议采用定量给食的饲喂方式,对试猪四肢观察结果表明,钙、磷水平最高的一种饲料,可在一定程度上缓解因生长过快造成的四肢病症. 相似文献
999.
1000.