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111.
New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch). 总被引:2,自引:0,他引:2
Shengmin Sang Karen Lapsley Robert T Rosen Chi-Tang Ho 《Journal of agricultural and food chemistry》2002,50(3):607-609
One new prenylated benzoic acid derivative, 3-prenyl-4-O-beta-D-glucopyranosyloxy-4-hydroxylbenzoic acid, and three known constituents, catechin, protocatechuic acid, and ursolic acid, have been isolated from the hulls of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the new prenylated benzoic acid derivative were accomplished on the basis of high-resolution 1D and 2D nuclear magnetic resonance data. All of these compounds except ursolic acid are being reported from almond hulls (P. amygdalus) for the first time. 相似文献
112.
李卫国 《中国农村水利水电》1992,(12)
该文用层次分析法(AHP)和德尔菲法(Delphi)相结合的系统分析法,对江西省上饶地区小水电科技发展领域分析模型作了探索,提出了小水电科技发展领域的优先度及重点,为“八五”、“九五”小水电科技规划的制定提供了依据,同时也为水利水电同行在科技规划中提供一点参考。 相似文献
113.
114.
Molecular identification and functional expression of porcine Toll-like receptor (TLR) 3 and TLR7 总被引:1,自引:0,他引:1
Sang Y Yang J Ross CR Rowland RR Blecha F 《Veterinary immunology and immunopathology》2008,125(1-2):162-167
To investigate porcine Toll-like receptors (TLR) responding to viral pathogen associated molecular patterns, the full-length cDNA of porcine TLR3 and TLR7 were identified and characterized. Porcine TLR3 and TLR7 cDNA encode 904- and 1050-amnio-acid polypeptides, respectively. Both porcine TLR3 and TLR7 contain typical functional TLR domains and share about 80% sequence identity to other mammalian orthologues. Tissue expression profiles showed that TLR3 was highly expressed in kidney, duodenum, spleen and liver, and moderately expressed in bone marrow, lung, and skin. Conversely, TLR7 was moderately and constitutively expressed in all tissues evaluated. Stimulation of mammalian cells transfected with porcine TLR3 and TLR7 constructs with TLR3 and TLR7 agonists [poly (I:C) and imiquimod (R837), respectively], and adenovirus elicited activation of interferon regulatory factors (IRFs). These data provide molecular and functional information for porcine TLR3 and TLR7, and implicate their role in mediating immune protection against porcine viral diseases. 相似文献
115.
不同株型冬小麦冠层结构特征多时相分析 总被引:1,自引:1,他引:1
同一株型不同生育期、不同株型相同生育期其结构参数均具有不同的变化特点,了解其变化,一方面有利于区分不同株型结构,进一步提高LAI(叶面积指数)等指标参数的遥感反演精度,另一方面可用于定量作物肥水管理,提高肥水利用效率。该文结合冬小麦整个生育期,在北京小汤山试验基地开展两期品种试验,对比分析实测冠层多角度光谱及结构参数,得出通过多角度光谱数据区分株型的最佳波段是红光波段,两期LAI与平均叶倾角(ALA)变化均表明,最佳时期为拔节期;起身期至拔节期所选试验品种均体现直立型品种LAI大于披散型品种。2009年试验表明利用J411 4月底LAI变化趋势差异也可较好的区分作物株型;披散型品种9428特征尺度变化出现“跷板”效应,可以作为株型识别的依据之一。 相似文献
116.
以巴西橡胶树无性系针选2号为试验材料,对橡胶树SSR-PCR反应的5个主要因素:TaqDNA聚合酶、Mg2 、引物、DNA模板及dNTPs进行优化试验。筛选出了各反应因素的最佳水平,建立了橡胶树SSR-PCR最佳反应体系(20μl):TaqDNA聚合酶0.8U;Mg2 浓度为1.5mmol/L;引物浓度0.5μmol/L;模板DNA含量50ng;dNTPs浓度0.25mmol/L。并利用此反应体系,用引物1对14个巴西橡胶树品种进行SSR分析,8%的非变性聚丙稀酰胺凝胶电泳检测显示不同品种间DNA谱带多态性丰富。结果证明,此反应体系是稳定可靠的。这为下一步进行的遗传多样性分析、指纹图谱构建等研究奠定基础。 相似文献
117.
设计了一种基于ZigBee无线传感器网络的西瓜基质栽培智能灌溉系统。该系统由环境信息采集装置、信息处理系统和灌溉执行结构3部分组成。环境信息采集装置主要采集影响西瓜水分需求的基质相对湿度和空气相对湿度;信息处理系统对数据进行分析与处理,判断是否驱动灌溉执行机构对西瓜进行灌溉。综合考虑西瓜在不同生长阶段基质相对湿度、空气相对湿度对西瓜需水量的影响,建立了模糊控制规则库,利用MATLAB进行仿真,证明灌溉策略的有效性。结果表明,智能灌溉系统能根据智能灌溉策略适时、适量地进行灌溉,控制基质相对湿度与西瓜生长阶段相适应,伸蔓期将基质相对湿度控制在62.82%~67.25%,开花坐果期将基质相对湿度控制在68.05%~72.18%,膨瓜期将基质相对湿度控制在72.23%~77.15%,成熟期将基质相对湿度控制在58.36%~62.13%,所测得的基质相对湿度与最佳基质相对湿度之间的误差在2%左右,满足西瓜基质栽培的灌溉需求。 相似文献
118.
Effects of illite supplementation on in vitro and in vivo rumen fermentation,microbial population and methane emission of Hanwoo steers fed high concentrate diets 下载免费PDF全文
Ashraf A. Biswas Sung‐Sill Lee Lovelia L. Mamuad Seon‐Ho Kim Yeon‐Jae Choi Chanhee Lee Kichoon Lee Gui‐Seck Bae Sang‐Suk Lee 《Animal Science Journal》2018,89(1):114-121
This study was conducted to evaluate the effects of feeding supplemental illite to Hanwoo steers on methane (CH4) emission and rumen fermentation parameters. An in vitro ruminal fermentation technique was conducted using a commercial concentrate as substrate and illite was added at different concentrations as treatments: 0%, 0.5%, 1.0%, and 2.0% illite. Total volatile fatty acids (VFA) were different (P < 0.05) at 24 h of incubation where the highest total VFA was observed at 1.0% of illite. Conversely, lowest CH4 production (P < 0.01) was found at 1.0% of illite. In the in vivo experiment, two diets were provided, without illite and with addition of 1% illite. An automated head chamber (GreenFeed) system was used to measure enteric CH4 production. Cattle received illite supplemented feed increased (P < 0.05) total VFA concentrations in the rumen compared with those fed control. Feeding illite numerically decreased CH4 production (g/day) and yield (g/kg dry matter intake). Rumen microbial population analysis indicated that the population of total bacteria, protozoa and methanogens were lower (P < 0.05) for illite compared with the control. Accordingly, overall results suggested that feeding a diet supplemented with 1% illite can have positive effects on feed fermentation in the rumen and enteric CH4 mitigation in beef cattle. 相似文献
119.
Yong Hoon Lee Seungdon Lee Dong Hee Lee Sang Hye Ji Hyun Young Chang Sunggi Heu Jae Wook Hyun Dong-Soo Ra Eun Woo Park 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(1):97-102
Soil-borne cereal mosaic virus (SBCMV) causes a severe disease in susceptible cultivars of winter wheat. The virus is vectored by the soil-borne protist
Polymyxa graminis. Experiments were conducted to investigate whether SBCMV RNA2 could persist in seed from SBCMV-infected susceptible cultivars
of winter wheat. Over 7,000 seedlings were generated from seed collected from two cultivars of SBCMV-infected winter wheat.
Seedlings were grown in a glasshouse compartment and batch tested for the presence of SBCMV using real-time RT-PCR. The majority
of batches tested positive for SBCMV, indicating an RNA2 transmission rate of 1.8–9.4% in wheat. The presence of the virus
was confirmed by amplifying and sequencing a larger (400 bp) fragment of viral RNA2 in a sub-set of the seedlings testing
positive by real-time RT-PCR. Root extracts from this sub-set tested negative for P. graminis using real-time PCR. The implications for disease epidemiology of this virus are discussed.
The authors are British Civil Servants and as such their work is subject to British Crown Copyright. This means the exclusive
copyright for the article cannot be transferred. 相似文献
120.