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151.
152.
Mature inflorescences of 76 samples of ten genera of native grasses were collected in the Ankara province of Turkey. Microscopic
examination of individual seeds revealed the presence of endophytic fungi in four seed samples, The endophytes were isolated
in pure culture and identified. Seeds were also ground and subjected to ELISA and HPLC analyses to confirm the levels of ergot
alkaloids typically produced by endophytic fungi of grasses. 相似文献
153.
Summary The plant species Papaver somniferum L. (opium poppy) is grown commercially in several countries under secure area to produce opium and its major alkaloids i.e. morphine, codeine, thebaine, narcotine and papaverine for pharmaceutical industries. In recent years the global demand for these alkaloids and its derivatives are growing. Seeing the global demand there is urgent need to develop high opium yielding varieties integrated with high specific alkaloids. However, a breeding programme focused on developing improved varieties requires knowledge about the genetic variability for the concern traits. Therefore the present investigation was undertaken to examine phenotypic and genotypic variability, broad sense heritability, genetic advance under selection and interrelationship of traits. A total of 122 accessions were found to be highly variables for all the traits studied. Broad sense heritability ranged from 74.18% (for opium yield/plant) to 99.00% (for papaverine content). Expected genetic advance was varied between 33.91% (for morphine content) and 257.46% (for papaverine content). Genetic correlation analysis revealed that opium yield is negatively correlated with morphine and papaverine content. Among alkaloids codeine, thebaine, narcotine and papaverine showed positive correlation among themselves. The correlations among alklaloids were justified based on the biosynthetic pathway of opium alkaloids. 相似文献
154.
Summary A productive yellow flowered mutant with high tropane alkaloid content was isolated in the M2 generation of gamma irradiated (Co60 at 40 kr) progenies ofHyoscyamus niger. Mutant progenies, on an average, were capable of synthetising more than twice crude alkaloid (0.147% to 0.221%) in M3 through M6 generations compared to the parental control (0.065 to 0.106%). In pilot scale trial (M7), two elite lines, Y-15 and Y-17 were found to contain 0.390% and 0.318% crude drug in contrast to 0.211% in an improved inbred used as control. However, owing to conducive plant morphology, Y-17 registered high yield of dry biomass, hence gave more than double yield of crude drug than the improved control (inbred) (23 kg/ha against 11 kg/ha). Also being superior in hyoscyamine and hyoscine yields, it was redesignated as var.Aela, and released for commercial cultivation in India, thus signifying the efficiency of radiation breeding for crop improvement. 相似文献
155.
The effect of drought stress at three growth stages on seed alkaloid content in two sweet (W26 and Polonez) and one bitter variety (Zubr) of spring sown Lupinus angustifolius L. was investigated in a lysimeter experiment on sandy soil in Denmark. Full irrigation resulted in medium alkaloid content. Drought stress during the vegetative phase increased alkaloid content to 0.094, 0.192 and 2.55% of seed dry matter, respectively. At the flowering stage alkaloid content decreased to 0.070, 0.152 and 1.99%, while drought stress during pod-filling increased alkaloid content for the determinate variety W26 to 0.097%, but decreased it to 0.161 and 1.98% for the two indeterminate varieties Polonez and Zubr, respectively. Drought during either flowering or pod-filling resulted in an increased mean seed weight and a reduced number of seed per square metre. Alkaloid content was negatively correlated to seed weight. The alkaloid composition differed for the three genotypes, and was affected by drought treatment. Compared to the bitter variety the sweet varieties were characterized by reduced concentrations of lupanin, 13-hydroxylupanin and angustifolin, whereas spartein, isolupanin and isoangustifolin were little affected. 相似文献
156.
用甲醇、乙醇、丙酮、氯仿、乙酸乙酯、苯、石油醚等7种溶剂对骆驼蓬种子进行冷浸提取。提取率分别为23.91%。18.68%.17.80%,18.49%,14.31%.15.13%,17.96%。7种提取物中.以种子乙醇提取物(ESPH)对斜纹夜蛾3龄幼虫的非选择性拒食活性最高。24h拒食率为70.15%。采用酸水总生物碱提取法对ESPH进行初步分离。得到氯仿、正丁醇、水及总生物碱萃取物。生物测定结果表明.总生物碱萃取物对斜纹夜蛾幼虫的生长发育抑制作用最为强烈,其次为氯仿萃取物。 相似文献
157.
禾草内生真菌生物碱可以增强寄主植物的抗逆性,为了解禾草内生真菌生物碱的研究现状和发展趋势,基于Web of Science数据库,对20年来(2000-2019年)国内外发表的禾草内生真菌生物碱论文进行检索筛选,以禾草内生真菌生物碱为关键词,共检索到646篇相关文献,其中我国33篇。对相关文献进行计量学分析发现:生物碱发文数量排名前三的国家是美国、新西兰和中国;文献平均被引次数最多的是中国;20年来,我国关于禾草内生真菌生物碱的文章数量稳步上升,且不断有文章被国际高水平的期刊发表。我国禾草内生真菌生物碱的研究单位主要集中在兰州大学和南开大学等高校,研究内容主要是生物碱生物学特征、生态作用以及影响共生体产碱的因素等。而关于生物碱致毒机理和人工合成途径的研究较少,今后需加强对其的深入研究。 相似文献
158.
模拟酸雨,改变施肥与遮荫条件,利用紫外分光光度法和高效液相色谱法测定半夏中总生物碱、鸟苷和腺苷质量分数的变化.结果表明:酸雨胁迫在一定程度上降低了半夏块茎的鲜物质量及总生物碱、鸟苷和腺苷质量分数,pH值为2.0和3.5时较为显著;在施肥与遮荫处理条件下,施肥(每株施肥量为NH4NO3:2 g,NaH2PO4:2 g,K2SO4:2 g)与1层遮荫(自然全光照的20%)的复合处理对半夏块茎鲜物质量的增长及总生物碱、鸟苷和腺苷质量分数的提高最为显著. 相似文献
159.
乌头属植物物种极为丰富,是我国重要的药用植物之一。对我国乌头属植物的化学成分和药理作用的研究近况进行了综述,以期为乌头属植物的开发利用提供一定参考。 相似文献
160.