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101.
[目的]为区分不同产地大黄药材的质量及鉴别提供依据。[方法]将供试材料青海玉树掌叶大黄(样品1)、青海海南唐古特大黄(样品2)与青海果洛唐古特大黄(样品3)分别粉碎成粉末,过100目筛,即可供X射线衍射试验用。设定管压30 kV,管流20 mA,2θ扫描范围3°~90°,扫描速度0.06°/s,每种样时间0.5 s,获得3种不同产区大黄的X-射线衍射图谱。试验数据以晶面间距d与特征峰相对强度L/Io表示,记为d/(I/Io)。将试验数据导入中药指纹图谱相似度计算软件,经选峰,设定匹配模板,将谱峰自动匹配,然后设定标准模板,进行谱峰差异性评价和整体相似性评价。[结果]样品1中所含的化学成分与样品2相同,但峰的强度(I/Io)不同,表明相同成分在两种样品中的含量不相等。同样把样品3的图谱与其他两个样品进行比较,也会得到相同的衍射峰值。表明不同产区的大黄中各化学成分的含量有差异,但其衍射图谱及衍射峰值具有一定的指纹特征。[结论]X-射线衍射法是鉴别不同产区的大黄及其他中药材的一种快捷有效的方法。 相似文献
102.
【目的】筛选适宜鹰嘴紫云英的 EMS 诱变条件。【方法】以鹰嘴紫云英品种甘绿 2 号种子为试验材料,采用不同浓度(0、0. 2%、0. 4%、0. 6%、0. 8%)的甲基磺酸乙酯(EMS)进行不同时间(2、4、 6、8 h)的诱变处理,探究 EMS 对鹰嘴紫云英种子萌发特征及表型变化的影响。【结果】低浓度和短时间 EMS 处理促进鹰嘴紫云英种子的萌发,随 EMS 浓度升高和诱变时间的增加,对鹰嘴紫云英种子萌发产生抑制作用。种子浸出液电导率随诱变条件的加深呈上升趋势,在 2~6 h 时,萌发期发芽率、发芽势、幼苗苗长和根长均随处理时间和诱变浓度的增加呈先升高后降低的趋势,在 8 h 处理下,随 EMS 浓度的增加呈逐渐降低趋势,EMS 浓度在 0. 8% 时,种子发芽率和发芽势均达到最低,较对照分别降低了 54. 45% 和 56. 67%;经形态学筛选,发现有鹰嘴紫云英幼苗表现出幼苗矮小、停滞生长、叶片黄化、宽叶、窄叶、叶片发紫、诸多病斑等特殊变异性状。【结论】0. 8%EMS 处理 6 h 可作为最佳诱变组合;幼苗的生长随诱变时间和浓度增加而明显受到抑制,且表型变异类型也逐步增多。 相似文献
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An antigen was prepared from metabolic products which were produced by maintaining Fasciola hepatica adults in RPMI tissue culture medium for 24 h. The antigen compared favourably with a soluble extract of adult flukes when used in an enzyme-linked immunosorbent assay (ELISA). Experimentally infected calves were used to evaluate the sensitivity of the test and a survey from areas of both traditionally high and low incidence of the disease was carried out. Evidence is presented which suggests that this metabolic antigen could be used for the sero diagnosis of naturally occurring infections. In addition the use of a microcomputer to read, file and analyse the results enabled a very large number of samples to be processed daily. 相似文献
107.
Comparison of media used for the primary isolation of Mycobacteriurm bovis by veterinary and medical diagnostic laboratories 总被引:1,自引:0,他引:1
Veterinary and medical laboratories engaged in the cultural diagnosis of bovine or human tuberculosis were requested to supply samples of the media that they routinely use for the primary isolation of M. bovis. Fourteen laboratories supplied 7 basic media types; these were Lowenstein-Jensen, Stonebrink's, modified Middlebrook 7H11 agar, tuberculosis bovine blood agar, egg yolk agar, Gerloff's egg and Herrold's egg yolk. Two strains of M. bovis were used to test the media, strain AN5, a glycerol-tolerant laboratory strain and M86/90 a glycerol-sensitive wildtype strain. AN5 grew well on all media with the exception of Herrold's and strain M86/90 did not grow on media containing glycerol and grew poorly on Herrold's medium. It is recommended that Lowenstein-Jensen with pyruvate (but without glycerol), Stonebrink's, modified Middlebrook 7H11 and tuberculosis bovine blood agar should be considered the media of choice for the primary isolation of M. bovis. Egg yolk agar also proved adequate for this purpose in the trial. This medium may be suitable for routine use but to date experience with its use is limited. 相似文献
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P F Nettleton J S Gilmour J A Herring J A Sinclair 《Comparative immunology, microbiology and infectious diseases》1992,15(3):179-188
From 1985 to 1989 lambs persistently infected with border disease virus (BDV) were produced for comparative immunological studies by infecting 57 susceptible pregnant ewes between 50 and 60 days' gestation with Moredun or Oban strains of BDV. Ewes were infected either by injection with virus grown in cell culture or by housing with lambs excreting BDV. There was no significant difference in the outcomes of these different methods of infection. There was a significant difference in the number of viable lambs born to ewes receiving the two viruses. Of 41 ewes infected with Moredun virus 21 produced 32 live lambs of which 17 were reared to 1 month old (53% viability). Of 16 ewes receiving Oban virus 10 gave birth to 17 live lambs of which 15 were reared to 1 month old (88% viability). All the lambs born to ewes infected with Moredun BDV had varying signs of tremor and increased hairiness ("hairy-shakers") while those born to ewes infected with the Oban virus had no obvious clinical signs. Survival of the lambs was poor. Up until February 1991, 14 Moredun and 10 Oban sheep between the ages of 4 months and 5.5 yr had died from a variety of causes. The two commonest causes were a chronic wasting syndrome and a mucosal disease-like syndrome which was associated with the recovery of cytopathic BDV. Mating of unrelated persistently infected sheep was largely unproductive although 2 lambs were reared. 相似文献