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991.
白菜型无花瓣油菜突变体的花器官形态特征   总被引:7,自引:1,他引:7  
在我国白菜型油菜地方品种余井花籽和国外白菜型油菜品种Am032中同时发现了无花瓣突变体。通过对白菜型油菜无花瓣突变体与甘蓝型无花瓣油菜及正常油菜器官形态的鉴定和比较,认为白菜型油菜无花瓣突变体的花瓣缺失突变机制与甘蓝型油菜不同,白菜型油菜无花瓣突变体有花瓣转变成雄蕊的现象,推测白菜型油菜花瓣缺失突变可能与花器官同源异型基因突变有关。  相似文献   
992.
提取乙烯诱导香蕉后熟初期的果皮总蛋白和对照果皮总蛋白,进行双向电泳实验,利用ImageMaster软件找出乙烯诱导的香蕉果皮中的差异蛋白点,并且对差异蛋白进行质谱分析,选取一个可能为Ⅲ类酸性几丁质酶(MaCHⅢ)的蛋白进行后续研究.利用MaCHⅢ的肽段信息在NCBI上比对后找到与该蛋白相应的核酸信息,设计PCR反应引物,扩增MaCHⅢ基因,得到DNA全长序列.结果表明,该基因与Ⅲ类酸性几丁质酶的同源性为99%,可以初步确定这个基因为Ⅲ类酸性几丁质酶基因.  相似文献   
993.
《Rice》2012,5(1):3

Background

Since whole genome sequences of rice were made publically accessible, the number of articles on new rice genes has increased remarkably. The Committee on Gene Symbolization, Nomenclature and Linkage (CGSNL) of the Rice Genetics Cooperative published the gene nomenclature system for rice and encouraged researchers to follow the rules before publishing their results. The CGSNL provides an on-line registration system for newly identified rice genes to prevent conflicts and/or duplication of gene name in journal articles.

Findings

Recently, the CGSNL surveyed genes in the rice WRKY family in published journal articles and found several duplicated gene names.

Conclusions

To discuss and resolve inconsistencies in WRKY gene nomenclature, the rice WRKY working group was established and redefined the nomenclature. This report announces the conclusion.  相似文献   
994.
玉米低钾耐性性状的主基因+多基因遗传分析   总被引:2,自引:0,他引:2  
应用植物数量性状主基因+多基因混合遗传模型多世代联合分析方法,以玉米缺钾症状叶片数为指标,对1个耐低钾玉米自交系T和2个低钾敏感玉米自交系S1和S2配制成的2个组合的P1、P2、F1、B1、B2和F2世代进行遗传分析,研究明确玉米耐低钾性状的遗传机制。结果表明,玉米低钾耐性遗传在2个组合中都由1对加性+加性-显性多基因控制;主基因遗传率(F2)平均为60.43%,多基因遗传率(F2)平均为15.35%;T×S1组合的遗传变异占表型变异值为80.20%,T×S2组合的遗传变异占表型变异值为71.35%,表明耐低钾性状以主基因遗传为主。育种应用上可以在低世代进行这一目标性状的选择。  相似文献   
995.
[目的]通过研究催乳素受体(PRLR)基因多态性,为松辽白鹅的选种与选育提供理论依据。[方法]参照鹅PRLR基因5′调控区序列设计引物,运用PCR-SSCP技术进行多态性分析。[结果]扩增片段存在多态性,得到AA、AB和BB 3种基因型,AA为优势基因型,等位基因A占主要优势;在PRLR基因5′调控区80处发生了单碱基突变(A→G)。[结论]PRLR基因5′调控区存在突变位点。  相似文献   
996.
[目的]对牛SLC27A1基因进行SNPs筛选并与中国荷斯坦奶牛的产奶性状进行关联分析,以期发现对中国荷斯坦奶牛产奶性状有显著影响的SNP位点。[方法]根据性能测定记录选取48头中国荷斯坦奶牛,提取血样DNA,组成2个DNA池,用于SNPs筛选,采用PCR-SSCP和克隆测序方法对DNA池进行SLC27A1基因SNPs筛选。针对发现的SNP位点,采用PCR-RFLP方法对另外231头中国荷斯坦奶牛进行群体基因型检测,采用SAS(8.02)GLM过程对各基因型与产奶性状进行关联分析。[结果]在exon3发现T112C位点,在3‘UTR发现G64A位点,T112C为同义突变;经PCR-RFLP检测,发现在T112C位点存在TT、TC、CC3种基因型,G64A位点存在GG、GA、AA3种基因型。2个位点均处于Hardy-Weinberg平衡状态。T112C位点的CC型个体的产奶量极显著高于TC型个体(P〈0.01),3种基因型对乳蛋白率和乳脂率影响均不显著(P〉0.05),乳蛋白率呈现CC〉TC〉TT的趋势,乳脂率呈现TT〉TC〉CC的趋势;G64A位点3种基因型对产奶量、乳蛋白率、乳脂率的影响均不显著(P〉0.05),但产奶量呈现GA〉GG〉AA的趋势,乳蛋白率和乳脂率呈现AA〉GG〉GA的趋势。[结论]该基因T112C位点与产奶量性状有一定的关联性,通过提高CC基因型频率有望提高中国荷斯坦奶牛的产奶量,SLC27A1基因可作为调控中国荷斯坦奶牛产奶量的候选基因,同时为该基因的标记辅助育种和进一步研究奠定了良好基础。  相似文献   
997.
Dried soil samples from many sources have been stored in archives world-wide over the years, but there has been little research on their value for studying microbial populations. Samples collected since 1843 from the Broadbalk field experiment on crop nutrition at Rothamsted have been used to document changes in the structure and composition of soils as agricultural practices evolve, also offering an invaluable record of environmental changes from the pre- to post-industrial era in the UK. To date, the microbial communities of these soils have not been studied, in part due to the well-documented drop in bacterial culturability in dried soils. However, modern molecular methods based on PCR amplification of DNA extracted directly from soil do not require bacterial cells to be viable or intact and may allow investigations into the legacy of bacteria that were present at the time of sample collection.

In a preliminary study, to establish if dried soils can provide a historical record of bacterial communities, samples from the Broadbalk soil archive dating back to 1868 were investigated and plots treated with either farmyard manure (FYM) or inorganic fertilizer (NPK) were compared. As anticipated, the processes of air-drying and milling greatly reduced bacterial viability whilst DNA yields declined less and may be preserved by desiccation. A higher proportion of culturable bacteria survived the archiving process in the FYM soil, possibly protected by the increased soil organic matter. The majority of surviving bacteria were firmicutes, whether collected in 2003 or in 1914, but a wide range of genera was detected in DNA extracted from the samples using PCR and DGGE of 16S rRNA genes. Analysis of DGGE band profiles indicated that the two plots maintained divergent populations. Sequence analysis of bands excised from DGGE gels, from a sample collected in 1914, revealed DNA from - and β-proteobacteria as well as firmicutes. PCR using primers specific for ammonia oxidizing bacteria showed similar band profiles across the two treatments in recently collected samples, however older samples from the NPK plot showed greater divergence. Primers specific for the genus Pseudomonas were designed and used in real-time quantitative PCR to indicate that archived soil collected in 1868 contained 10-fold less pseudomonad DNA than fresh soil, representing around 105 genomes g−1 soil. Prior to milling, dramatically less pseudomonad DNA was extracted from recently collected air-dried soil from the NPK compared to the FYM plot; otherwise, the two plots followed similar trends. Overall bacterial abundance, diversity and survival during the archiving process differed in the two soils, possibly due to differences in clay and soil organic matter content. Nevertheless, the results demonstrate that air-dried soils can protect microbial DNA for more than 150 years and offer an invaluable resource for future research.  相似文献   

998.
采用PCR方法扩增出苜蓿银纹夜蛾(Autographa californica)核型多角体病毒(AcMNPV)几丁质酶基因(chiA)编码区1.6kb全长片段,并将该片段分别克隆至原核表达载体pET30a和杆状病毒BactoBac表达系统转移载体pFastBac中,分别在大肠杆菌(Escherichia coli)BL21(DE3)和草地贪夜蛾(Spodoptera frugiperda)细胞系Sf-9中进行了表达。SDS-PAGE分析表明,在大肠杆菌和昆虫细胞中均有效表达了60kD的蛋白。将表达产物饲喂5龄棉铃虫(Helicoverpa armigera)幼虫后取其围食膜,扫描电镜结果显示,围食膜结构遭到破坏形成大量孔洞。生物测定结果表明,以上两种表达产物对苏云金芽孢杆菌(Bt)和核型多角体病毒(NPV)均具有增效作用。以AcMNPVChiA在大肠杆菌和细胞系Sf-9中的表达产物分别与BtCry2Ac蛋白混合饲喂棉铃虫初孵幼虫,增效率分别为33.4%和54.5%,其LT50较对照处理分别缩短了17.8和20.6h;当AcMNPVChiA在大肠杆菌和细胞系Sf-9中的表达产物分别与甘蓝夜蛾(Mamestra brassica)核型多角体病毒(MbNPV)混合处理棉铃虫初孵幼虫时,其LT50与对照比较分别缩短了16.6和22.4h。  相似文献   
999.
在拟南芥中,NPR1是系统获得抗性SA信号传导途径中的一个重要的调节因子,在水稻中已克隆到与之同源的OsNPR1基因。构建OsNPR1基因水稻过量表达载体,并将其转化粳稻TP309得到转基因植株;通过自交纯合,得到17个纯合株系;对T3、T4代纯合株系进行PCR鉴定,证实转基因纯合株系中外源伪OsNPR1基因具有遗传稳定性;检测了T1、T2代转基因株系和T3代转基因纯合株系对水稻白叶枯病病原细菌Xanthomonas oryzae pv.oryzae的抗病性,结果表明,在T1、T2代中70%以上的株系对水稻白叶枯病的抗性显著提高,T3代中约67%的株系对水稻白叶枯病的抗性显著提高,说明这种抗病性的提高具有遗传稳定性。OsNPR1基因可作为选育水稻抗白叶枯病新种质的一个良好的候选基因。  相似文献   
1000.
Activin (AA, AB and BB) is a dimeric protein that belongs to the transforming growth factor- (TGF-) superfamily of growth factors and is involved in the regulation of many physiological and developmental processes. Recently, we have demonstrated that porcine activin stimulated goldfish gonadotropin-II (GTH-II) and growth hormone (GH) secretion from dispersed pituitary cells in static culture and pituitary fragments in perifusion. The action of activin in the goldfish is unique in that it has an acute stimulatory effect on the secretion of GTH-II and GH, whereas in mammals activin usually exhibits long-term stimulatory actions on FSH secretion. The action mechanism of activin is different from that of gonadotropin-releasing hormone (GnRH). Using domain-specific antibodies against mammalian activin subunits, we subsequently demonstrated the existence of immunoreactive activin subunits (A and B) in the goldfish ovary, testis, pituitary and brain, suggesting endocrine, paracrine and autocrine roles for activin in the regulation of goldfish reproduction. Both activin A and B subunits have been cloned from goldfish genome by polymerase chain reaction (PCR). Using the PCR fragments as probes, we have cloned a full length cDNA coding for activin B subunit from the goldfish ovary. Both activin A and B subunits show high homology to those of other vertebrates with the B subunit much more conserved (93 and 98% identity with human and zebrafish B subunit, respectively). The identity of the cloned B subunit was further confirmed by expression in the Chinese hamster ovary (CHO) cells and detection of the specific activity of activin in the culture medium. The messenger RNA of activin B subunit is expressed in a variety of goldfish tissues including ovary, testis, brain, pituitary, kidney and liver, suggesting a wide range of physiological roles for activin in the goldfish. We have also cloned a full length cDNA coding for the activin Type IIB receptor from the goldfish ovary, suggesting that activin may have paracrine or autocrine actions on the ovarian functions. The identity of the cloned receptor was confirmed by specific binding of125 I-activin on COS-1 cells transfected with the cloned Type IIB receptor.  相似文献   
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