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991.
ZHANG Hui-min Muhamaitijiang T SHI Jun WU Gui-ling Gulizhati Adili JIA Er-ken SU Zhan-qiang RAN Duo-liang Shayilan Kayizha LAN Ling YAO Gang LIU Jian-hua 《中国畜牧兽医》2017,44(9):2755-2760
In order to understand inflection of Newcastle disease virus (NDV) of Xinjiang wild birds, through analysis of molecular characteristics and genetic variation, to prevent the outbreak and spread of Newcastle disease, isolation of the virus was performed in 9 days old specific pathogen free (SPF) chicken embryos, detected the wild birds in Fuhai county which was located in the migration line of East Africa-West Asia by HA, HI test and RT-PCR method. And then 1 strain of NDV from wild birds was isolated, named as NDV/Pintail/CH(XJ)/01/2016. As the result, ORF of F gene from the NDV isolate was 1 662 bp, encoding 553 amino acids. The motif of the cleavage site was 112G-R-Q-G-R-L117, which was consistent with the characteristics of avirulent NDV strains. The phylogenetic analysis showed that NDV/Pintail/CH(XJ)/01/2016 nucleotide sequence homologies of F gene between reference strain Doneck/3/968 and mule Simeonovgrad strain homology were high and reached 99.7%, it belonged to genotype Ⅱ of Class Ⅱ NDV. All of the three viruses had high homology to the vaccine strain La Sota,which were 99.5% to 99.8%. According to this research conclusion we provided evidence that poultry NDV outflowed into the natural environment. 相似文献
992.
WAN Chun-he LIU Rong-chang CHEN Cui-teng CHENG Long-fei FU Guang-hua FU Qiu-ling SHI Shao-hua CHEN Hong-mei HUANG Yu 《中国畜牧兽医》2017,44(10):3042-3048
In order to clarify the characteristics of the Hexon gene and the classification candidate of duck adenovirus A under the Adenoviridae family, the Hexon gene fragments of duck adenovirus A (designated as strain JX2016) were amplified. The results demonstrated that the cloned Hexon gene of duck adenovirus A (strain JX2016) was 2 733 bp in length, coding 910 amino acids. Nucleotide homology comparison showed that the strain JX2016 shared the highest nucleotide (99.8%) homology with reference strain FJ12025, also displayed higher than 99.4% nucleotide homology with other duck adenovirus A reference strains. However, the nucleotide homologies with strain GR (duck adenovirus 2, unclassified virus), Phelps (fowl adenovirus A) and P29 (goose adenovirus) were 54.5%, 53.6% and 55.2%, respectively. The genetic evolution analysis showed that all the duck adenovirus A strains were at the same subgroup, under the same Atadenovirus genus branch with ovine atadenovirus D (strain OAV287). Meanwhile, the duck adenovirus 2 (strain GR) at the same branch under Aviadenovirus genus branch with fowl adenovirus A (strain Phelps) and goose adenovirus (strain P29). Based on the Hexon protein genetic evolution analysis, we suggested renamed the duck adenovirus A as duck-origin atadenovirus and renamed the duck adenovirus 2 as duck-origin aviadenovirus. 相似文献
993.
In order to explore the genetic diversity and the classification status of the Chinese domestic pigs at the molecular level, the complete mitochondrial DNA (mtDNA) genomic sequences of 22 Chinese indigenous pig breeds from 6 types were downloaded from GenBank for the analysis using the bioinformatics method. The polymorphism of nucleic acid sequences was analyzed,the molecular phylogenetic tree based on D-loop sequences, Cytb gene, complete coding region mtDNA sequences and the Median-Joining network of the mtDNA D-loop haplotypes were constructed for 22 pig breeds from 6 types. The results showed that a total of 144 mutation sites among 22 pig breeds were detected, 22 haplotypes were discovered, which indicated that Chinese indigenous pig breeds had abundant genetic diversity. According to the complete mtDNA genomic sequences analysis, which suggested that the main mutations was transition, the transition/transversion ratio was greater than 2.0 and all mutations were in line with the neutral mutation. Our findings clearly demonstrated that there was a near genetic distance among 6 types, meanwhile, the shared haplotypes were found. The phylogenetic tree showed that Chinese indigenous pigs from 6 types were diverged from two ancestors.The results indicated that mtDNA D-loop and Cytb gene might serve as molecular markers for phylogenesis, origin and evolution. 相似文献
994.
为研究贵阳地区犬细小病毒(canine parvovirus,CPV)的流行基因型及其遗传进化情况,本试验对从贵阳市分离的10株CPV的VP2基因进行PCR扩增和克隆并进行序列分析。结果显示,分离的病毒能使F81猫肾细胞产生明显的细胞病变(CPE),分离的10株病毒中,7株为CPV-2a亚型,3株为CPV-2c亚型,命名为GY-1~GY-10。10株CPV分离株与疫苗株VP2基因的同源性98.4%~99.4%,与其他国内外参考株的同源性为97.7%~99.9%。本试验首次报道贵阳市CPV的流行基因型为CPV-2a亚型并伴随CPV-2c亚型存在,对监测CPV遗传变异趋势及疫苗的研制具有重要意义。 相似文献
995.
利用位于南京北郊的南京信息工程大学观测基地2010年各层(0、5、10、15、20、40、80、160、320 cm)地温数据,采用统计分析方法对南京北郊地温的变化特征进行了分析,揭示南京市浦口地区地温与时间、深度的变化关系。结果表明,南京北郊地区表层地温以及浅层地温有明显的季节变化和日变化,呈近似于正弦曲线的变化趋势。从地表到20 cm深时,地温的日变化逐渐减弱;当深度在40~320cm时,地温日变化已不明显。在垂直方向上,各层地温日变化幅值随着深度增加而减小,随着深度的增加峰值出现的时间逐渐滞后。 相似文献
996.
从Gen Bank数据库中获得20种鹿科动物的线粒体DNA序列全长,分析了序列碱基含量和遗传距离关系,并构建系统进化树,探讨了鹿科动物的系统进化关系。序列分析表明:鹿科动物线粒体DNA全长为16 305~16 482 bp,A+T含量约占62.58%,各物种间遗传距离为0.014~0.164。系统进化分析表明:驼鹿在鹿科动物中可能是最古老的;麋鹿与鹿属亲缘关系较近,支持将麋鹿划到鹿属的观点;泽鹿与花鹿属的斑鹿和豚鹿先聚到一起,支持将泽鹿划到花鹿属中;麂亚科中小麂可能是最原始的,赤麂和黑麂亲缘关系较近;獐与狍亲缘关系更近,建议将獐与狍划归到一个亚科。 相似文献
997.
《江西农业学报》2017,(7)
以江西省万年县为例,根据万年县测土配方数据,构建以思维进化算法、BP神经网络、四方位搜索法三者结合的模型(MEA-BPNN-F模型),同时加入高程和坡度信息来预测万年县耕地土壤有机质的空间分布,并与普通克里金法(OK模型)、以地理坐标为输入的BP神经网络模型(BPNN-G模型)、以高程和坡度作为辅助变量同时利用四方位搜索法加入邻近信息的BP神经网络模型(BPNN-F模型)进行比较。结果表明:4种模型的预测精度表现为MEA-BPNNFBPNN-FBPNN-GOK。应用MEA-BPNN-F模型预测精度最高、效果最好,比较符合土壤有机质地学运动规律及实际情况。该模型克服了BP神经网络全局搜索能力差和收敛速度慢的缺点,提高了BP神经网络的泛化能力。 相似文献
998.
以胡萝卜为试材,采用分子生物学和生物信息学方法对胡萝卜14-3-3基因家族各成员进行鉴定,研究分析其理化特性、基因结构、保守结构域、复制事件、系统进化及顺式作用元件,以期为进一步研究胡萝卜14-3-3蛋白的功能提供参考依据。结果表明:胡萝卜中共鉴定到11个14-3-3基因,不均匀分布在6条染色体上,含有3~7个外显子,其中1对基因发生片段复制事件;编码的蛋白序列长度为236~264 aa,分子量为26.64~30.14 kD,等电点为4.65~5.33,具有7个Motif,全部为酸性非分泌型蛋白,定位在细胞核。系统进化分析显示,胡萝卜14-3-3蛋白分为ε类(3个)与非ε(8个)类2个亚族。此外,顺式作用元件分析结果表明,胡萝卜14-3-3基因含有大量激素与逆境胁迫相关元件。 相似文献
999.
1000.
本文利用金属离子催化鲁米诺-过氧化氢反应,通过比较几种结构不同的微流控芯片,对影响检测发光信号灵敏度的因素,如试剂浓度、流速和微通道的尺度等作了详细地讨论。提出了具有双螺旋形结构芯片的微流动注射系统,大大增强了化学发光检测的灵敏度。在最佳实验条件下,铬离子(Cr3+)浓度在5.0 × 10 -9 ~ 2.0 × 10 -6 mol/L范围内与其体系的发光信号强度具有一定的线性关系,对浓度为6.0×10?8 mol/L的铬连续11次进样,相对标准偏差为1.59 %,其检出限为1.50×10-9 mol/L。该体系成功地用于天然湖水和自来水中金属铬的分析和检测。 相似文献