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951.
Four new sesquiterpenes, myrrhterpenoids K-N (1-4) have been isolated from the resin of Commiphora myrrha. Their structures and relative configurations were elucidated by spectroscopic methods (IR, ESIMS, HR-ESIMS, 1D and 2D NMR). Compounds 1 and 4 showed neuroprotective effects against MPP(+)-induced neuronal cell death in SH-SY5Y cells. 相似文献
952.
953.
Human-wildlife conflict (HWC) is a conservation concern that increasingly threatens the continued existence of some of the world's most endangered species. With an increase in human population, urban sprawl and subsequent encroachment on wild land, human and wildlife interaction has become inevitable. In the majority of cases, this interaction results in a negative outcome for humans, wildlife or both. In China, these key elements, along with a decrease in wild prey species, have resulted in the expansion of HWC encounters, and the need for alleviating this conflict has become a conservation priority. Loss of human life, livestock and/or crops is most often the catalysts that fuel HWC. Techniques to alleviate conflict around the world have included preventative measures and mitigation techniques, such as financial compensation and other incentive programs. Both types of measures have had variable success. We review the current status of human-carnivore conflict management in China, and, drawing lessons from around the globe, we make recommendations for improving conservation management in China. For example, an increase in law enforcement in nature reserves is vital to reducing human disturbance in prime carnivore habitat, thereby reducing conflict encounters. Also, modifications to current wildlife compensation programs, so that they are linked with preventative measures, will ensure that moral hazards are avoided. Furthermore, investigating the potential for a community self-financed insurance scheme to fund compensation and increasing efforts to restore wild prey populations will improve the outcome for wildlife conservation. Ultimately, HWC management in China will greatly benefit from an integrative approach. 相似文献
954.
Two clonal trial stands of Chinese Fir (Cunninghamia lanceolata) were used in this study, one was 19-year-old stand which included 38 clones, and the other was 17-year-old stand including 102 clones.The statistical analyses showed that there were very significant genetic variations in height, DBH,volume and ratio of heartwood(Rhw),wood basic density(ρb ) of the clones in the two stands. The repeatability of clones was in median to high level,and the genetic CV was different over the all five traits.There were very significant phenotypic and genetic correlations among height,DBH and volume,and negative correlations among growth, Rhw andρb.The selection method experiment indicated that index selection could improve volume, Rhw andρb,showing synthetically superior selection effects compared to any individual trait selection methods. 相似文献
955.
956.
五大连池重碳酸矿泉水中Mn、Ni离子的健康风险评价 总被引:1,自引:0,他引:1
根据五大连池重碳酸矿泉水中Mn、Ni离子的水质监测数据,采用美国环境保护署(USEPA)推荐的水环境健康风险评价模型,对重碳酸矿泉水中金属离子Mn、Ni通过饮水途径引起的健康风险进行了评价。结果表明:五大连池重碳酸矿泉水富含Mn、Ni离子,并且Mn、Ni离子含量高于《饮用天然矿泉水》的标准。但是成人每天饮用2.2L五大连池重碳酸矿泉水,矿泉水中躯体毒物质Mn、Ni离子所引起的健康风险度低于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平5.0×10-5a-1。表明直接饮用五大连池重碳酸矿泉水,Mn、Ni离子对人体健康不会造成危害。 相似文献
957.
利用山东省统计年鉴及社会统计公报数据,运用引力模型、旅游经济隶属度模型,对2004~2010年山东省17个地级市旅游经济联系的时空差异进行了定量研究,结果表明:2004~2010年山东省城市旅游经济联系,时空差异明显,鲁中和鲁东地区的城市旅游经济联系强于鲁西地区,城市旅游经济连系呈现不规则的"H"型空间结构模式;泰安的旅游地位和作用突出,济南和青岛的旅游影响力下降。经济发展水平、旅游区位、旅游基础设施、旅游资源、旅游政策等因素共同构成山东省时空差异的动力机制。 相似文献
958.
本研究根据GenBank中鸭新城疫病毒(NDV)的F基因和鸭圆环病毒(DuCV)的V1/rep基因的保守序列,各设计一对特异性引物,并对二重PCR的扩增条件进行优化,建立了鸭NDV和DuCV的二重PCR检测方法。对混合样品进行扩增,得到2条大小为493bp(鸭NDV)和218bp(DuCV)的特异性条带,与预扩增片段相符。而对番鸭细小病毒、鸭瘟病毒、鸭肝炎病毒、鸭源小鹅瘟病毒、鸭H9亚型流感病毒、鸭疫里氏杆菌、大肠杆菌、禽多杀性巴氏杆菌等病原检测,结果为阴性。该方法的敏感性试验表明,鸭NDV的核酸最小量为40fg,DuCV为20fg。 相似文献
959.
960.