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101.
猴头菌培养及提取工艺的研究 总被引:1,自引:0,他引:1
本文对猴头菌培养条件包括营养,温度,水份等以及提取工艺进行了研究。采取三级培养,固体发醇后提取浸膏,生产工艺简便。浸膏特征反应明显,且各种理化指标符合《中国药典》(1990)煎膏剂通则的要求。猴头菌Hericium einaceus近年来已有很多厂家利用菌丝体提取物,制成各种剂型的药物,用于治疗十二指肠溃疡病,胃窦炎,慢性胃炎,胃闷胀,胃痛等病,是一种治疗消化道疾病具有明显疗效的真菌药物。对此,我 相似文献
102.
显微注射Ca^2+激活小鼠M Ⅱ期卵母细胞 总被引:2,自引:0,他引:2
胞质内显微注入Ca^2+可以激活小鼠M Ⅱ期卵母细胞,且随着卵龄的增加,激活率明显升高。卵龄小于16h(hCG注射后)注射Ca^2+引起的激活率很低,卵龄超过18h,激活率达到50%以上。卵龄小于16h的卵母细胞,卵内注入超纯水未能激活卵母细胞,而在18 ̄19h卵龄组,注射水的对照组激活率为35%,但显著或极显著地低于注射Ca^2+的试验组。激活前注射EDTA卵母细胞的激活率约为30%,激活后注射 相似文献
103.
104.
葡萄果实cDNA文库的构建及鉴定 总被引:1,自引:0,他引:1
构建葡萄果实cDNA文库是研究果实发育相关基因表达调控的基础工作.本实验从巨峰葡萄果实中提取了高质量的RNA,利用MMLV反转录酶把总RNA中的mRNA反转录成cDNA第一链,用特异引物进行LD-PCR扩增合成双链cDNA.将分级纯化的带有粘性末端双链cDNA与λTrip Ⅰ Ex2载体连接,重组载体体外包埋成为cDNA原始文库.初步鉴定原始文库的滴度为1.32×106 pfu/mL,文库扩增后滴度达1.45×1010 pfu/mL.从扩增文库中随机挑取250个克隆进行PCR鉴定,结果表明重组率为98.7%,插入片段大小在0.5~2.0 kb之间,因此,本研究成功构建了葡萄果实cDNA文库. 相似文献
105.
Eight malting cultivars of barley released from 1944 to 1998 in Argentina were sown in two growing seasons to evaluate the
effect of breeding on malting quality. An adequate grain weight and screening percentage as in the older varieties were maintained
in the recent releases. The grain protein concentration decreased in the modern cultivars together with a decreased in C-and
an increased in B-hordein. These results were achieved without a clear trend through the time. Malt extract was increased
by 0.054% per year in the period analysed and the most important contribution in the quality improvement was the introduction
of Beka (known as a high quality cultivar released in Europe) in1966. There was not a clear trend in the breeding process
to obtain more stability between years in the quality attributes, at least, in the characteristics analysed in the present
study. Conversely, malt extract was less variable and this tendency was observed through the years of release of the cultivars.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
106.
采用生物统计的正交试验设计方法,研究了M199、犊血清(CBS)、鸡胚提取物(CEE50)、兔肝提取物(RLE50)、丙酮酸钠(SP)、水解酪蛋白(CH)和酵母提取物(YE)在离体培养中对乳突类圆线虫第三期幼虫存活和生长发育的影响。结果表明,只有CBS和RLE50。对第三期幼虫的存活和生长发育起着显著的促进作用、在试验得出的最适含量组合的培养基内,幼虫生长发育最好,存活时间最长为37d。对M199、EMEM、F12和RPMI1640这4种商品组织培养基进行了筛选试验;结果显示M199最佳,表明脂溶性维生素可能是乳突类圆线虫的离体培养所需营养之一。 相似文献
107.
不同浸提条件对包膜控/缓释肥水中溶出率的影响 总被引:11,自引:5,他引:11
以几种不同包膜材料控/缓释肥为供试肥料,研究不同肥(养分)水比、浸提方式(连续浸提和更换浸提液)、温度和pH条件对控/缓释肥水中溶出率的影响。结果表明,浸提液中肥料浓度是影响养分释放的重要因素,加大肥水比、更换浸提液可以显著减小这种影响。升高温度,有机和无机材料包膜控/缓释肥水中溶出率均显著加快。肥料类型、肥水比对浸提液的pH都有显著影响,但在连续浸提和更换浸提液方式下,7d内浸提液的pH有着不同的变化趋势。控/缓释肥在pH.5的磷酸盐缓冲液中的溶出率显著高于在pH.7的磷酸盐缓冲液中的溶出率。因此,对于不同包膜材料控/缓释肥以一定pH值的微酸性缓冲溶液作为浸提剂,定期更换浸提液或采用动态流法,相同的氮(或磷、钾)水比,30℃左右的浸提条件是较为合理的。 相似文献
108.
Summary Although organic solvents such as methanol and ethanol have been shown to act as energy sources for denitrifying microorganisms, no studies on the influence of organic solvents on denitrification in soil have been reported. Organic solvents have been used as an aid in the application of pesticides and other agricultural chemicals to soil, in studying the effects of these chemicals on denitrification in soil. During these applications, the soil is often aerated or heated to remove the solvent while leaving the chemical in the soil. The work reported here shows that treating soils with methanol, ethanol, or acetone had a very marked effect on their denitrifying ability, even when the soils were aerated thoroughly or heated at 50°C to remove these solvents. This indicates either that it is not possible to effect complete removal of organic solvents from soils by aeration or heating or that organic solvents promote denitrification by solubilizing a fraction of soil organic matter that is not available to denitrifying microorganisms before the addition of these solvents. Experiments using phenylmercuric acetate (a herbicide and nitrification inhibitor) showed that although this compound had a marked inhibitory effect on denitrification when added to soil in methanol, ethanol, or acetone, it had no inhibitory effect on denitrification when added to soil in water. The work reported shows that the use of an organic solvent in adding an agricultural chemical to soil can lead to erroneous conclusions in studies on the effects of the chemical on soil denitrification. 相似文献
109.
Jinhe Bai Anne PlottoRobert Spotts Nithiya Rattanapanone 《Postharvest Biology and Technology》2011,62(2):204-212
The objective of this study was to evaluate the use of an ethanol vapor release pad and a saprophytic yeast Cryptococcus infirmo-miniatum (CIM) to reduce decay and maintain postharvest quality of intact or fresh-cut sweet cherries (Prunus avium) cv. Lapins and Bing. Intact or fresh-cut fruit were packed in perforated clamshells (capacity 454 g) and stored at 1, 10 or 20 °C for up to 21, 14 and 8 d, respectively. For ethanol treatment, a pad made with silica gel powder containing 10 g ethanol and covered with perforated film, which allows ethanol vapor to diffuse gradually, was attached to the upper lid of the clamshells. Ethanol treatment caused accumulation of ethanol in the packaging headspace, about 10 μL L−1 with little change within 14 d at 1 °C, 23 μL L−1 at d 1 and decreased to 15 μL L−1 at d 10 at 10 °C, and 26 μL L−1 at d 1 and decreased to 13 μL L−1 at d 3 at 20 °C. Ethanol content in fruit was less than 9 mg kg−1 in all the control fruit, and increased to 16, 34 and 43 mg kg−1 in ethanol-treated fruit at 1, 10 and 20 °C, respectively. Nonetheless, a sensory taste panel did not perceive any flavor difference from the ethanol treatment. The ethanol treatment retarded softening, darkening, and acid decrease in fruit as well as discoloration of the stems, and extended shelf-life of intact cherries. Ethanol reduced brown rot (Monilinia fructicola) in fresh-cut cherries stored at 20 °C, but not at 1 and 10 °C. A pre-packaging dip in CIM completely controlled brown rot in inoculated fresh-cut cherries stored at 1 °C, and in naturally infected cherries at 20 °C. 相似文献
110.
金钱草提取液化学组分的GC—MS分析及在卷烟加香中的应用 总被引:1,自引:0,他引:1
应用挥发油蒸馏器萃取金钱草提取液,采用气相色谱—质谱分析技术(GC-MS)分析了金钱草提取液的成分和相对含量。对金钱草提取液在卷烟中进行了添加试验,发现添加于烟草薄片中可以改善其口感,起到生津止渴的作用,以达到除杂、减刺和增香的目的,从而提高和改善薄片的品质和使用价值。 相似文献