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81.
82.
Transverse thin cell layers (tTCLs) of protocorm-like bodies of two stages of PLBs (30 d and 60 d old) of Cymbidium Sleeping Nymph were used as explants to induce PLBs by using coconut water (CW) as a natural additive. 5% (v/v) CW supplemented to KC medium induced an average of 5 PLBs per responding tTCL of 30 d old PLBs with 83% of responding tTCLs. A low percentage of responding tTCLs were observed in 60 d old PLBs’ tTCLs. Anatomical and confocal microscopic studies traced the origin of PLBs to subepidermal layers of the tTCL. A significantly high percentage of shoot regeneration was obtained from PLBs formed on 1–10% (v/v) CW from tTCLs of 30 d old PLBs in comparison to PLBs induced on control after first subculture on KC medium (without CW). The induced PLBs regenerated into plantlets with velamenous roots and these plantlets were transferred to greenhouse conditions on cocopeat:perlite (9:1) with nearly 100% survival. Post-transfer performance of the plantlets was monitored. The results suggest tTCLs as potential explants (with respect to economy of precious hybrid materials) which can overcome the slow growth of hybrid PLBs and coconut water as a single natural additive for the mass multiplication of commercially important orchids. 相似文献
83.
研究冬虫夏草子实体的生长发育和形成规律,为冬虫夏草人工培殖及资源保护提供理论依据。将老熟待僵化的幼虫,在不同温度、基质含水量和光照条件下培殖,观察子实体形成与伸展情况。研究表明,子实体分化与形成需要0℃左右低温刺激,变温有利于子实体的形成;子实体的生长还需要有充足的水分及高湿环境,在子实体生长期间,应保持基质含水量为60%~80%,相对湿度95%~100%为宜;微弱的光照都能诱导子实体产生,子实体有向光性生长的特性。环境因子对冬虫夏草子实体形成及伸展具有重要作用。 相似文献
84.
Protein bodies ontogeny and localization of prolamin components in the developing endosperm of wheat caryopses 总被引:1,自引:0,他引:1
During caryopsis development, prolamins are initially stored in individual protein bodies, then generate a protein matrix in the ripe caryopsis. The ontogeny of the protein bodies was analyzed by fluorescence and electron microscopy from 7 to 43 days after anthesis (dAA), a period of time from the cellularization of endosperm to its desiccation. A series of antibodies specific to each prolamin type (α/β-, γ-, ω-gliadins, low-molecular weight and high-molecular weight glutenin subunits) made it possible to localize and co-localize the different prolamins in organelles of endosperm cells at different developmental stages. Protein bodies containing prolamins were observed as early as 7 dAA. At the early developmental stages, protein bodies were spherical with diameters around 1–2 μm. Later, around 15 dAA, the PBs enlarged, and aggregation and/or coalescence were prominent at 21 dAA. From 33 dAA, individual PBs were no longer visible, but a protein matrix was confined in the space between starch granules. All prolamins were found in the same protein bodies, without any segregation according to their types. Immunochemical labelling of prolamins failed to reveal in TEM analyses any particular internal organization in protein bodies. Glutenin subunits and gliadins were observed in the Golgi apparatus at the early stages of endosperm development. 相似文献
85.
将围产期奶牛30头随机分为3组,每组10头。其中Ⅱ组为对照组,Ⅰ组和Ⅲ组分别为试验组;Ⅰ、Ⅱ、Ⅲ3组于产前28d开始分别饲喂NRC标准减少20%日粮(能量摄入80%组)、NRC标准日粮(能量摄入100%组)、NRC标准增加20%日粮(能量摄入120%组),产后各组奶牛均饲喂标准日粮,至产后56d结束,观察不同干物质摄入水平对奶牛血浆酮体浓度的影响。试验结果表明:奶牛产后干物质摄入量和产奶量均为Ⅰ组高于Ⅱ组、Ⅱ组又高于Ⅲ组,经统计分析组间差异极显著(P<0.01)或差异显著(P<0.05);此外,Ⅰ组体重消耗最小,Ⅲ组体重消耗最大,各组间差异极显著(P<0.01)。产后Ⅲ组血酮浓度显著高于Ⅰ组和Ⅱ组(P<0.05),而Ⅰ组和Ⅱ组之间差异不明显。可见,围产期奶牛不同干物质摄入量与产奶量、体重等生产性能及产后血酮浓度之间存在着密切的关系。 相似文献
86.
SPOT-5卫星影像中水体信息自动提取的一种有效方法 总被引:10,自引:0,他引:10
从卫星遥感影像中快速、准确地提取水体信息已成为水资源调查,水资源宏观监测及湿地保护的重要手段,但目前,进行水体提取所使用的卫星遥感数据的分辨率较低,使其应用的深度和广度受到严重约束。本文利用波段运算得到特征波段(PRWI),经过图像增强处理后提取水体和居民地混合信息,在此基础上通过分析水体的光谱特征,发现水体和居民地在近红外和短波红外上有显著差异,采用决策树模型将水体专题信息提取出来。运用目视判读和定量统计方法来评价提取结果。结果表明,该方法的总体提取效果较好,其提取精度与常规的监督分类方法相比有了较大的提高。经检验发现其误判的像元主要是位于水体和其他地物的交界处。 相似文献
87.
南京地区奶牛酮病病因和诊断的研究 总被引:10,自引:0,他引:10
泌乳早期母牛采食精料不足及精料能量水平偏低所致的能量负平衡是南京地区奶牛酮病的一个主要原因;干乳期精料饲喂过量,可能使产后母牛食欲恢复变慢,而加剧能量负平衡,促进酮病发生;有些产后疾病常影响食欲而导致继发性酮病。诊断学研究表明,乳汁中丙酮加乙酰乙酸含量明显低于血液值,故使用一般酮粉检测乳酮,将会使一些亚临床病例漏检,因此作为其诊断方法并不可靠。 相似文献
88.
Christopher MM Pereira JL Brigmon RL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1992,21(1):3-8
An automated method for measuring beta-hydroxybutyrate was adapted to the Ciba-Corning 550 Express trade mark random access analyzer. The assay was based on a kinetic reaction utilizing hydroxybutyrate-dehydrogenase. Beta-hydroxybutyrate concentration (mmol/L) was calculated ratiometrically using a 1.0 mmol/l standard. Canine serum, plasma, and urine were used without prior deproteinization and only a 30-microliter sample was required. The method demonstrated good linearity between 0 to 2 mmol/l of beta-hydroxybutyrate. Analytical recovery (accuracy) within these concentrations ranged from 85.8 to 113.3%. Both within-run and day-to-day precision were determined, as was specificity of the assay in the presence of a variety of interfering substances. The automated assay was rapid and economical, with reagent stability maintained for at least 2 weeks at 4 degrees C. This assay can readily be applied toward the assessment of ketoacidosis in dogs, and with further validation, other species. 相似文献
89.
90.
黑龙江省暴雨洪涝灾害风险区划 总被引:2,自引:0,他引:2
以黑龙江省81个气象台站1961-2008年的逐日降水数据、社会经济资料、地理信息数据以及灾情数据为基础,运用GIS技术,对黑龙江省暴雨洪涝灾害的致灾因子危险性、孕灾环境敏感性、承灾体易损性等评价因子进行综合分析,采用加权综合分析法以及GIS中自然断点分级法,构建了暴雨洪涝灾害风险评估模型,将黑龙江省划分为高、次高、中等、次低和低5个等级风险区.结果表明,黑龙江省暴雨洪涝灾害风险呈“东西高-南北低”的分布,松嫩平原大部、三江平原北部和南部地区处于高-次高风险区,哈尔滨西北部、大庆东南部、绥化北部和西部以及鹤岗中部地区,属于高风险区;而大兴安岭地区和东南半山区处于低-次低风险区,发生暴雨洪涝灾害的几率较低.灾情验证结果表明,实际灾情的高值-次高值分布与风险区划结果基本符合,风险区划模型具有较高的实际应用价值和研究意义. 相似文献