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31.
对东方粘虫Mythimna separate(Walker)中肠V-ATPase H亚基基因(VATPH)进行克隆、原核表达及纯化。首先采用RT-PCR技术克隆基因,再构建原核表达载体(pET15b-VATPH)并转入E.coil BL21(DE3),经异丙基硫代-β-D-半乳糖苷(isopropyl-β-D-thiogalactoside,IPTG)诱导表达,用Ni-NTA柱及S-200分子筛纯化,最后进行SDS-PAGE分析。结果表明,pET15b-VATPH可高效表达V-ATPase H亚基,纯化后可获得单一条带且分子质量约为55ku的重组蛋白。该结果为进一步研究V-ATPase H亚基的晶体结构,药物小分子与H亚基大分子的相互作用,尤其是以H亚基为筛选模型创制新农药奠定基础。 相似文献
32.
为给四川小麦品质育种提供参考信息,利用7个HMW-GS、17个LMW-GS和1个1B/1R易位的特异分子标记,对105份2000年后育成的四川小麦品种进行上述基因检测。结果表明:(1)针对HMWGS,在Glu-A1位点,含Ax2*的品种有2份,频率为1.9%;在Glu-B1位点,含Bx7、Bx20、Bx17、By8和By9的品种分别有73、26、4、45和30份,频率分别为69.5%、24.8%、3.8%、42.9%和28.6%,未检测到含Bx7OE的品种;在Glu-D1位点,含Dx5的品种有65份,频率为61.9%。(2)针对LMW-GS,在Glu-A3位点,含Glu-A3a、Glu-A3b、Glu-A3c、Glu-A3d和Glu-A3f的品种分别有2、2、63、29和9份,频率分别为1.9%、1.9%、60.0%、27.6%和8.6%,未检测到含Glu-A3e和Glu-A3g的品种;在Glu-B3位点,含Glu-B3b、Glu-B3d、Glu-B3f、GluB3g和Glu-B3i的品种分别有18、10、1、75和1份,频率分别为17.1%、9.5%、1.0%、71.4%和1.0%,未检测到含Glu-B3a、Glu-B3c、Glu-B3e和Glu-B3h的品种。(3)含1B/1R易位的品种有36份,频率为34.3%。(4)组合6种和5种以上优质基因的品种分别有2份(频率为3.8%)和15份(频率为14.3%)。可利用这些品种作为亲本,在四川小麦品质育种中逐步导入优质基因Ax2*、Bx7、By8、Dx5、Glu-A3d、Glu-B3d、Glu-A3b和Glu-B3b,并淘汰1B/1R易位,优化四川小麦面筋优质基因组成。 相似文献
33.
布鲁氏菌病是一种严重危害人和动物健康的人畜共患病,人群感染主要来源于感染的动物及被污染的畜产品,目前疫苗免疫仍是控制动物布鲁氏菌病的主要措施。现有国际参考疫苗主要有牛种疫苗株S19和羊种疫苗株Rev.1,这些疫苗为动物群布鲁氏菌病控制提供重要保障的同时也存在关键的技术瓶颈问题,如安全性差,接种动物出现流产;血清抗体体内持续时间较长,干扰常规诊断等。随着布鲁氏菌基因组测序工作的相继完成及DNA重组技术的发展,新型布鲁氏菌病疫苗的开发成为研究的热点。亚单位疫苗本着其较高的安全性和有效性,在动物群布鲁氏菌病控制过程中具有较大的应用前景。笔者综述了布鲁氏菌病疫苗的发展史,并对布鲁氏菌病亚单位疫苗的研究进展进行概述。 相似文献
34.
蚕豆蛋白亚基是蚕豆种子贮藏蛋白重要组成部分,深入鉴定蚕豆蛋白亚基,对了解蚕豆种子蛋白不同亚基的结构和功能具有重要意义。本研究应用液相色谱、电喷雾离子化与串联质谱联用技术和生物信息技术对蚕豆种子贮藏蛋白6个特异亚基进行了质谱鉴定。结果表明:这些特异亚基中的64、47、42及38ku分别鉴定出4个蛋白:豌豆球蛋白、豆球蛋白前体、假定糖结合蛋白、LEGB7_VICFA;97ku亚基蛋白为分子伴侣GroEL;96ku亚基蛋白由6个具有不同代谢功能的蛋白组成。 相似文献
35.
C. C. Whitehead 《The Veterinary quarterly》2013,33(3):150-157
Summary There are two metabolic disorders of major commercial importance in poultry that involve the occurrence of fatty deposits in the liver. Fatty Liver and Kidney Syndrome (FLKS) affects young birds and the main manifestations, lipid infiltrations into liver and many other organs, are apparently secondary effects of the primary lesion that lies in carbohydrate metabolism. Although several nutritional and environmental factors influence FLKS, the main factor is the vitamin, biotin. In the absence of an adequate supply of biotin, the hepatic activity of pyruvate carboxylase, a biotin‐dependent enzyme, becomes so low that gluconeogenesis in the liver via pyruvate becomes negligible. When the bird is then subject to a mild stress and 1or short term fasting, liver glycogen reserves become rapidly depleted and a progressive hypoglycaemia develops that ultimately proves fatal. Supplementing diets with adequate amounts of biotin can prevent the syndrome. Fatty Liver Haemorrhagic Syndrome (FLHS) is brought about by an excessive accumulation of fat in the livers of adult hens which weakens the cellular structure of the liver and allows fatal haemorrhaging to occur. The aetiology of the syndrome is not clear, but a major factor is an excessive intake of dietary energy. However, Me involvement of hormonal and toxicological factors, as well as other nutritional factors, is also possible. 相似文献
36.
Summary Gelprotein or SDS-insoluble gel-forming glutenin was isolated from wheat flour by extraction with an aqueous 1.5% SDS solution. Remarkable intervarietal differences were observed both in amount and subunit composition of these proteins.The amount of gelprotein and the SDS-sedimentation volume both proved to be good parameters for the bread-making quality of wheat cultivars. A high correlation was observed between amount of gelprotein and SDS-sedimentation volume. The amount of gelprotein was therefore tentatively assumed to be the essential basis of the SDS-sedimentation test.The subunit composition of the gelprotein was studied by SDS-PAGE after reduction of SS bonds by mercaptoethanol. It was found that the average bread-making quality of wheat cultivars and progeny of the cross Atlas 66 x Atys which possessed subunits 3 and 10, coded for by chromosome 1D, was significantly higher than that of wheat samples possessing subunit 2 and 11, their allelic counterparts. 相似文献
37.
The suitability of wheat varieties for bread‐making depends on their glutenin subunits. The amino acid composition of these gluten building‐blocks have a strong influence on the rheology of the dough and, thus, on the suitability of the variety for bread‐making. This study reports a new x‐type high molecular weight glutenin subunit coded by the locus Glu‐A1 and named 2··. To investigate the impact of this allele on 10 quality parameters, a doubled haploid (DH) population of Triticum aestivum, segregating for Glu‐A1, was created. The statistical analysis demonstrates that, at Glu‐A1, the subunit 2·· is as favourable for quality as the subunit 2*. This is in accordance with results showing that the 2·· open reading frame still has the same number of cysteines as 2*. The small differences in the length of the central domain had no detectable effect on the elasticity, tenacity and baking quality, of the dough. 相似文献
38.
39.
Summary The endosperm storage proteins of 205 Chinese bread wheat cultivars and advanced lines were fractionated by SDS-PAGE to determine their high molecular weight (HMW) glutenin subunit composition. Seventeen alleles were identified: three at Glu-A1, eight at Glu-B1, and six at Glu-D1. The most common alleles were Null, 1, 7+8, 7+9, and 2+12. The results indicate that wheats from different regions differ in their frequencies of HMW glutenin subunits, however, none of the subunits could be related to specific environments. The glutenin quality scores of Chinese wheats ranged from 3 to 10, with an average of 6.7. Increasing quality scores have implications in improving steam-bread making quality for Chinese consumers. On the basis of HMW glutenin subunit composition, Chinese wheats are close to European wheats, especially Italian wheats because several Italian introductions are widely distributed in the pedigrees of Chinese wheat. 相似文献
40.
Limited but specific variations of seed storage proteins in Japanese common wheat (Triticum aestivum L.) 总被引:2,自引:0,他引:2
The electrophoretic banding patterns ofgliadin in common wheat lines derived fromJapan were determined byacid-polyacrylamide gel electrophoresis. For the 107 wheat lines used in our study,27 different patterns were identified, 13corresponding to the -gliadin, 8 tothe , -gliadin and 6 to the-gliadin. The gliadin patterns ofJapanese wheat cultivars and landracesgreatly differed from the patterns of wheatlines from other countries, and thevariation seen in wheat lines from Japanwas limited to 46 patterns. Sevencollection or breeding areas in Japanshowed different frequencies in theirgliadin patterns. Combining the gliadinpatterns with high molecular weightglutenin subunit compositions, 67combinations were observed. One gliadinpattern consisting of -gliadinpattern F, , -gliadinpattern H and -gliadin pattern Dwas frequently found in many Japanese wheatlines, though the other patterns werelimited to only one or two wheat lines. 相似文献