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1.
[目的]优化马齿苋ISSR-PCR反应体系与反应条件。[方法]以马齿苋为试验材料,采用改良的CTAB法提取总DNA,对ISSRPCR引物进行筛选,同时进行ISSR-PCR反应体系和反应条件的优化,电泳检测ISSR-PCR产物。[结果]8个ISSR引物适合马齿苋的ISSR-PCR分析;最适反应体系为总体系25.0μL,其中2×Taq Platinum PCR Master Mix 12.5μL,10μmol/L引物2.0μL,40 mg/L DNA模板1.0μL,dd H_2O 9.5μL;最适反应条件为94℃预变性360 s;94℃变性60 s,54℃退火60 s,72℃延伸90 s,30次循环;72℃再延伸300 s。[结论]建立了马齿苋ISSR-PCR扩增的最佳反应体系和扩增程序,为进一步研究马齿苋提供基础资料。 相似文献
2.
内标准基因对于转基因植物及其产品的定性定量PCR检测起着决定性的作用,木薯内标准基因的系统研究是木薯转基因成分检测的基础。在木薯的DFCI(http://compbio.dfci.harvard.edu/tgi/plant.html)数据库中,选择了有可能作为木薯内标基因的一些EST序列,包括亲环蛋白2(cyclophilin type 2,DB934316)、3-磷酸甘油醛脱氢酶基因B亚单位(Glyceraldehyde-3-phosphate dehydrogenase B subunit,TC445)GAPDH、Actin基因(TC2158与TC3381的拼接序列)、Alpha-tubulin(TC8072)基因,Polyubiquitin(TC9946),亚麻苦苷酶(linamarase,TC1540)6个基因序列,设计了7对定性PCR的引物(CP2、Actin、GAPDH、PUBQ2、Tublinα1、Tublinα2和LAM1),并进行了种内一致性、稳定性和种间特异性测试分析。结果表明,只有木薯的3-磷酸甘油醛脱氢酶基因B亚单位的GAPDH定性PCR引物扩增系统在木薯的22个不同品种中都能够得到一致性稳定性的扩增结果,在大戟科其他植物及其他非大戟科植物没有发现非特异性扩增产物。另外6个基因(CP2、Actin、PUBQ2、Tublinα1、Tublinα2和LAM1)的定性PCR引物扩增系统在大戟科其他植物及非大戟科植物中都有非特异性的扩增产物。因此GAPDH定性PCR引物扩增系统初步符合内标准基因的种内一致性,稳定性,种间特异性的特点,可应用于转基因木薯成分定性PCR检测。 相似文献
3.
基于马尔科夫链蒙特卡洛(简记为MCMC)模拟的参数贝叶斯估计,对改进的广义帕累托分布(简记为MGPD)模型进行了优化,并利用该模型得到了地质灾害损失的在险损失值(简记为VaR)和条件损失值(简记为CVaR).以湖南娄底市地质灾害损失数据进行实证分析及模型适应性检验,结果表明:优化后的模型不仅具有很好的极值数据描述能力,而且具有较强的适用性. 相似文献
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运用马尔科夫链方法预测陕西苹果花期冻害年型 总被引:4,自引:0,他引:4
依据陕西29个苹果基地县1971~2007年4月极端最低气温资料,将陕西果区苹果花期冻害年型划分为严重冻害(NTd≤-2℃≥10),中等冻害(NTd≤-2℃<10 & NTd≤0℃≥15),轻度冻害(NTd≤-2℃<10 & NTd≤0℃<15 & NTd≤2℃≥19),和正常年型(NTd≤-2℃<10 & NTd≤0... 相似文献
6.
P deficiency is a major obstacle for crop production in subtropical red soils in South China, and the hydrolysis of organic P (Po) is of great significance in these soils due to the immobilization of P by Fe and Al. Cover cropping in orchards and symbiotic microbial inoculation are considered to improve soil quality, including P status, however, their effects on the hydrolysis of Po is little known. In this study, five soil managements were established in a guava orchard in South China for two and a half years, including clean culture (CC), cover cropping with Paspalum natatu (PN), PN with arbuscular mycorrhizal fungal inoculation (PNA), cover cropping with Stylosanthes guianensis (SG), SG with rhizobial inoculation (SGR). Soil chemical, biochemical and microbial properties were analyzed. Results indicate that soil pH and SOM content tended to increase following cover cropping alone or with microbial inoculation. Po content was significantly elevated in PNA. Po fractionation revealed that cover cropping alone or with microbial inoculation significantly affected the contents of moderately labile Po (MLPo) and moderately resistant Po (FAPo). Enzyme assay indicated that cover cropping with microbial inoculation increased the activities of acidic phosphomonoesterase (ACP), neutral phosphomonoesterase (NP) and alkaline phosphomonoesterase (ALP), with ALP the most sensitive, although ACP activity dominated in red soils. Correlation analysis suggested a significantly positive relationship between ALP activity and MLPo or FAPo. PCR-DGGE profile of the alp-harboring bacterial community showed that cover cropping with S. guianensis and mycorrhizal inoculation to P. natatu promoted the bacterial diversity and/or species richness. For almost all the measured parameters, PN and SG were comparable, however, PNA was superior to SGR, indicating the stronger additive effect of arbuscular mycorrhizal fungus than that of rhizobia. Cat-PCA indicated that MLPo was the most influential factor on phosphomonoesterase. In general, this study suggests that, in subtropical orchards with red soil, cover cropping with microbial inoculation can improve the Po hydrolysis via the promoted alp-harboring bacterial community and then ALP activity. Our results also suggest that the combination of P. natatu and arbuscular mycorrhizal fungus is better than S. guianensis and rhizobia, which possesses practical significance for sustainable production in these orchards. 相似文献
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8.
采用水蒸气蒸馏法对新疆地钱和钝叶光萼苔等2种苔类植物挥发油进行提取,并用气相色谱—质谱联用技术进行分离鉴定;采用峰面积归一化法确定各成分的质量分数。结果表明:地钱挥发油中共分离出24种成分,确认了其中的22种成分;钝叶光萼苔挥发油中共分离出25种成分,确认了其中的19种成分,两者主要成分为烯萜类和醇类化合物。 相似文献
9.
利用从西安住宅市场上调研收集的数据,根据住宅产业价值链系统结构,运用构建的住宅产业价值链价值分布测算模型——熵权-模糊综合评价模型对西安市住宅产业价值链价值分布进行了剖析。研究表明,西安市住宅产业价值链存在太过于依赖土地价值与资金价值,而投资分析、建设、营销服务等阶段价值创造能力过低,以及整体价值创造水平偏低等问题。因此,建议通过完善住宅产业的外包制度、调整土地供应制度、构建合理价值分配机制、建立价值创造联盟制度、构筑住宅产业虚拟价值链与价值网络等途径,来优化西安市住宅产业价值链价值分布格局,以促进产业升级。 相似文献
10.
Rotfinder is a non-destructive decay-sensing apparatus based on resistance measurements in standing trees. The accuracy of Rotfinder in detecting decay was evaluated in 500 standing trees in three Norway spruce (Picea abies) plots. Trees were measured at three heights, 0.30, 0.66 and 1.30 m. Sections were later inspected for the presence of decay and reaction zones. Inspected trees were mostly infected by Heterobasidion annosum and showed a large variation in the amount of decay present, ranging from 0.1% to 88.0% of the section. Correctly and incorrectly classified trees were compared in terms of ion and element concentration, density and moisture. Measurements at stump level (0.30 m) were more accurate than measurements at breast height (1.30 m) where the reaction zone and decay columns showed lower moisture content. The accuracy of Rotfinder increased when trees with small decay columns were regarded as ‘non-decayed’. When only trees with more than 15% of the section decayed were regarded as ‘decayed’, Rotfinder had an accuracy of 0.86 when performing assessments at stump level. False negatives, as opposed to true positives, corresponded to trees with smaller and drier decay columns, drier reaction zones and lower K+ (potassium) concentration in the decay column. False positives corresponded to trees with large sapwood and high sodium content in the sapwood. Rotfinder represents an alternative to the standard method of using increment core observations to assess decay in living trees. 相似文献