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91.
试验采用温湿度二因素回归最优设计,研究贵烟4号变黄阶段烘烤环境与烤后烟叶石油醚提取物含量及香吃味的关系,结果表明:在温度32℃~42℃、相对湿度75%~95%范围内,随着变黄温湿度的逐渐升高,烤后烟叶石油醚提取物含量及香吃味评吸得分均表现出先逐渐增加而后又下降的趋势;在控制变黄温度约37℃~38℃,相对湿度84%~90%即干湿差约1.5℃~2℃烤后烟叶石油醚提取物含量及香吃味评吸得分较高;分析结果还表明,烤后烟叶的石油醚提取物含量与香吃味评吸得分表现出较好的相关性。 相似文献
92.
伪狂犬病病毒Fa株gp63(gI) 基因核苷酸序列测定及分析 总被引:2,自引:0,他引:2
对我国最早分离的伪犬病病毒(pseudorabies virus,PRV)Fa株糖蛋白gp63(gI)基因核苷酸序列及的氨基酸序列作了测定与分析,完整的gp63(gI)结构基因从起始密码子ATG到终止密码子TGA共有1050个核苷酸残基,编码由439个氨基酸残基构成的多肽链,4种核苷酸残基的构成比分别为:G35.9%,11.33%,T11.81%,C40.95%,G C含量达76.85%,PRV Fa株gp63基因核苷酸序列与Nice株的相比,两者同源性达98.13%,仅存在3个核苷酸残基的缺失变异,氨基酸推导序列分析表明,糖蛋白gp63具有典型膜蛋白特征,与Nice株相比,同源性为97.42%,gp63基因起始密码子由3个连续的ATG组成,ATG上游区域内无启动子调控区序列。 相似文献
93.
从中国发病鸡群中分离的鸡减蛋综合征病毒(EDSV)AA-2株,经常规方法提取其病毒核酸后,构建了限制性内切酶PstⅠ及HindⅢ水解片段的基因文库。对其中HindⅢ-F片段(52.9~58.9mu)的正反2条链的序列测定发现,其反链存在1个编码容量为387个氨基酸(aa)的开放读码框架(openreadingframe,ORF),经Genebank/EMBL同源搜寻后证实其编码产物为EDSV的DNA结合蛋白(DBP)。与其他腺病毒DBP的氨基酸序列进行同源比较,其N端同源性在19.0%~46.2%之间,C端同源性在27.7%~60.4%之间。腺病毒DBP的3个保守序列CR1,CR2,CR3在EDSVDBP中有较大变化,但EDSVDBP的锌指框架(Zn2+fingermotif)却保留了对其功能必需的残基。 相似文献
94.
Purdie AC Plain KM Begg DJ de Silva K Whittington RJ 《Comparative immunology, microbiology and infectious diseases》2011,34(3):197-208
Paratuberculosis (Johne's disease), caused by Mycobacterium avium subspecies paratuberculosis, is responsible for significant economic losses in livestock industries worldwide. This organism is also of public health concern due to an unconfirmed link to Crohn's disease. Susceptibility to paratuberculosis has been suggested to have a genetic component. In livestock, a number of candidate genes have been studied, selected on their association to susceptibility in other mycobacterial diseases, their known role in disease pathogenesis or links to susceptibility of humans to Crohn's disease. These genes include solute carrier family 11 member 1 (SLC11A1, formerly NRAMP1), toll-like receptors, caspase associated recruitment domain 15 (CARD15, formerly NOD2), major histocompatibility complex (MHC) and cytokines (interleukin-10 and interferon-gamma) and their receptors. Genome wide association studies have attempted to confirm associations found and identify new genes involved in pathogenesis and susceptibility. There are a number of limitations and difficulties in these approaches, some peculiar to paratuberculosis but others generally applicable to identification of genetic associations for complex traits. The technical approaches and available information for paratuberculosis have expanded rapidly, particularly relating to sheep and cattle. Here we review the current published evidence for a genetic association with paratuberculosis susceptibility, technological advances that have progressed the field and potential avenues for future research. 相似文献
95.
The aim of the present study was to determine the whole nucleotide sequence of the open reading frame of the sex‐determining region Y (SRY‐ORF) in wild sika deer. The SRY gene of wild sika deer was obtained by polymerase chain reaction (PCR) with DNA from blood samples. The whole nucleotide sequence of the SRY‐ORF in wild sika deer consisted of 687 bp and encoded 229 deduced amino acids. In comparison with the bovine SRY gene, the percentage of nucleotide sequence homology was 91.0% in the overall ORF, and those of the N‐terminal, high mobility group (HMG) box, and C‐terminal regions within ORF were 88.9%, 96.2% and 87.9%, respectively. The nucleotide sequences of sika deer SRY‐ORF characterized in the present study can be used for phylogenetic analysis or sexing in wild sika deer. 相似文献
96.
97.
H. Khatib I. Zaitoun Y.M. Chang C. Maltecca & P. Boettcher 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(1):26-28
In dairy cattle, many studies have reported quantitative trait loci (QTL) on the centromeric end of chromosome 14 that affect milk production traits. One of the candidate genes in this QTL region – thyroglobulin (TG) – was previously found to be significantly associated with marbling in beef cattle. Thus, based on QTL studies in dairy cattle and because of possible effects of this gene on fat metabolism, we investigated the association of TG with milk yield and composition in Holstein dairy cattle. A total of 1279 bulls from the Cooperative Dairy DNA Repository Holstein population were genotyped for a single nucleotide polymorphism in TG used previously in beef cattle studies. Analysis of 29 sire families showed no significant association between TG variants and milk production traits. Within‐sire family analysis suggests that TG is neither the responsible gene nor a genetic marker in association with milk production traits. 相似文献
98.
根据猪链球菌2型(strep tococcus su is type 2)溶血素基因(sly)设计和合成了一对可扩增其完整阅读框的引物,对HA 9801等6株猪链球菌2型江苏分离株、1株德国分离株SS2-D及猪链球菌C群参考株ATCC 35246的核酸进行PCR扩增,结果显示HA 9801等6株江苏分离株及德国株SS2呈阳性,ATCC 35246呈阴性。HA 9801株PCR产物纯化后测序,序列分析结果表明该DNA片段与猪链球菌2型1933株的sly基因同源性为99%。 相似文献
99.
对鸡O2血清型致病性大肠杆菌1型菌毛fimI基因进行了扩增并与国外同源菌株基因序列进行了比较。结果表明:两者核苷酸同源性达98.42%,预测氨基酸顺序同源性达98.92%。fimI基因的预测氨基酸序列中仅第46位氨基酸由ALA变为THR,第76位氨基酸由SER变为ALA,其余核苷酸的变化未影响氨基酸的翻译,推测,这种改变是由分离株的差异所引起的。 相似文献
100.
鸭生长激素(GH)基因编码区及调控区多态性分析 总被引:1,自引:0,他引:1
根据鸭生长激素基因编码区及调控区的序列设计8对引物,利用PCR-SSCP方法对北京鸭、西湖野鸭、樱桃谷鸭、金定鸭、山麻鸭、荆江鸭、绍兴鸭、缙云麻鸭等8个鸭种进行单核苷酸多态性分析。结果共发现3个突变位点,分别为230处(C→G)、244处(C→A)和3 701处(C→T)。前两处突变位于5′调控区,3 701处突变位于编码区第4外显子,但该编码区的突变是沉默突变,3′调控区表现了高度的保守性。统计结果发现:⑴在5′调控区基因座上,金定鸭的等位基因B频率显著高于其他品种;⑵在外显子4基因座上,基因型频率的分布与品种有关,且肉用型鸭的CC基因型频率显著高于蛋用型。可以推测,本研究所检测到的基因座可能与生产性能相关。 相似文献