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21.
棉花单核苷酸多态性标记研究进展 总被引:1,自引:0,他引:1
单核苷酸多态性标记已在农作物研究中得到广泛应用并取得重大进展。为了便利棉花SNP(Single nucleotide polymorphism)标记的研究和应用,介绍了利用基因芯片、简化基因组测序、重测序等在棉花中开发SNP标记的方法 ,综述了SNP标记在棉花遗传图谱构建、数量位点的定位和分子标记辅助育种、基因组测序以及系统进化等研究中的应用。并对异源四倍体棉花中SNP标记开发时,同源序列位点和部分同源序列位点上的SNP标记辨别问题进行了系统探讨,对其快捷的开发、检测方式和在数量基因定位中的应用前景进行了展望。 相似文献
22.
计算机辅助设计被广泛应用于设计行业中。文中分析总结园林专业计算机辅助设计相关教学工作过程中存在的问题,提出解决问题的对策,探讨如何采用"一图制"的模式合理地进行一体化案例教学,使高校教学紧密结合实际工作过程及工作任务,为计算机辅助设计教学提供参考。 相似文献
23.
甘蓝型油菜SRAP、SSR、AFLP和TRAP标记遗传图谱构建 总被引:27,自引:0,他引:27
以黄籽GH06为母本、黑籽P174为父本杂交得到的第6代重组自交系188个株系为作图群体,通过SRAP、SSR、AFLP和TRAP四种分子标记对该群体进行遗传连锁分析,构建了一张包含20个连锁群、300个标记位点的甘蓝型油菜分子遗传图谱(LOD≥3.0),包括202个SRAP标记、65个SSR标记、23个AFLP标记和10个TRAP标记。图谱总长度1273.7cM,标记间平均距离为4.25cM。连锁群上的标记数在4~56个之间,连锁群长度变动在37.1~109.2cM之间,群内平均图距在1.80~14.20cM之间。LG1包含的标记最多,有56个;标记最少的连锁群(LG9、LG18、LG20)只有4个。LG13的平均图距最大,为14.20cM;LG6的平均图距最小,仅为1.80cM。在整个图谱上,存在图距大于20cM的空隙6个。本研究首次将SRAP及TRAP标记用于甘蓝型油菜遗传图谱的构建,结果表明,SRAP及TRAP标记在甘蓝型油菜遗传图谱的构建上是一种良好的标记系统。 相似文献
24.
The gene Pi15 for resistance of rice to Magnaporthe grisea was previously mapped to a ≈0.7-cM region on chromosome 9. To further define the chromosomal region of the Pi15 locus, a contig spanning the locus was constructed, in silico , through bioinformatics analysis using a reference sequence of the cultivar 'Nipponbare'. One simple sequence repeat marker adopted from the International Rice Microsatellite Initiative and six candidate resistance gene (CRG) markers, developed from gene annotation of the reference sequence of the contig, were used for linkage analysis in a mapping population consisting of 504 extremely susceptible F2 plants. The Pi15 locus was delimited to a ≈0.5-cM region flanked by the markers CRG5 and CRG2 and co-segregated with the markers BAPi15782 , CRG3 and CRG4, which was physically converted to a 44-kb interval. 相似文献
25.
Takayoshi?OharaEmail author Yeon-Sang?Song Hikaru?Tsukazaki Tadayuki?Wako Tsukasa?Nunome Akio?Kojima 《Euphytica》2005,144(3):255-263
Summary The first genetic linkage map of Japanese bunching onion (Allium fistulosum) based primarily on AFLP markers was constructed using reciprocally backcrossed progenies. They were 120 plants each of (P1)BC1 and (P2)BC1 populations derived from a cross between single plants of two inbred lines: D1s-15s-22 (P1) and J1s-14s-20 (P2). Based on the (P2)BC1 population, a linkage map of P1 was constructed. It comprises 164 markers – 149 amplified fragment length polymorphisms (AFLPs), 2 cleaved amplified polymorphic
sequences (CAPSs), and 12 simple sequence repeats (SSRs) from Japanese bunching onion, and 1 SSR from bulb onion (A. cepa) – on 15 linkage groups covering 947 centiMorgans (cM). The linkage map of P2 was constructed with the (P1)BC1 population and composed of 120 loci – 105 AFLPs, 1 CAPS, and 13 SSRs developed from Japanese bunching onion and 1 SSR from
bulb onion – on 14 linkage groups covering 775 cM. Both maps were not saturated but were considered to cover the majority
of the genome. Nine linkage groups in P2 map were connected with their counterparts in P1 map using co-dominant anchor markers, 13 SSRs and 1 CAPS. 相似文献
26.
Chickpea wilt caused by Fusarium oxysporum f. sp. ciceris is one of the major yield limiting factors in chickpea. The disease causes 10–90% yield losses annually in chickpea. Eight
physiological races of the pathogen (0, 1A, 1B/C, 2, 3, 4, 5 and 6) are reported so far whereas additional races are suspected
from India. The distribution pattern of these races in different parts of the world indicates regional specificity for their
occurrence leading to the perception that F. oxysporum f. sp. ciceris evolved independently in different regions. Pathogen isolates also exhibit differences in disease symptoms. Races 0 and 1B/C
cause yellowing syndrome whereas 1A, 2, 3, 4, 5 and 6 lead to wilting syndrome. Genetics of resistance to two races (1B/C
and 6) is yet to be determined, however, for other races resistance is governed either by monogenes or oligogenes. The individual
genes of oligogenic resistance mechanism delay onset of disease symptoms, a phenomenon called as late wilting. Slow wilting,
i.e., slow development of disease after onset of disease symptoms also occurs in reaction to pathogen; however, its genetics
are not known. Mapping of wilt resistance genes in chickpea is difficult because of minimal polymorphism; however, it has
been facilitated to great extent by the development of sequence tagged microsatellite site (STMS) markers that have revealed
significant interspecific and intraspecific polymorphism. Markers linked to six genes governing resistance to six races (0,
1A, 2, 3, 4 and 5) of the pathogen have been identified and their position on chickpea linkage maps elucidated. These genes
lie in two separate clusters on two different chickpea linkage groups. While the gene for resistance to race 0 is situated
on LG 5 of Winter et al. (Theoretical and Applied Genetics 101:1155–1163, 2000) those governing resistance to races 1A, 2, 3, 4 and 5 spanned a region of 8.2 cM on LG 2. The cluster of five resistance
genes was further subdivided into two sub clusters of 2.8 cM and 2.0 cM, respectively. Map-based cloning can be used to isolate
the six genes mapped so far; however, the region containing these genes needs additional markers to facilitate their isolation.
Cloning of wilt resistance genes is desirable to study their evolution, mechanisms of resistance and their exploitation in
wilt resistance breeding and wilt management. 相似文献
27.
28.
甜瓜结实花初花节位QTL分析 总被引:3,自引:1,他引:2
以WI998为母本(纯雌株、厚皮网纹甜瓜品系),TopMark为父本(雄全同株纯合品系),配置杂交组合,利用单粒传得到171个株系的重组自交系(F2S4)群体构建甜瓜SSR分子标记遗传连锁图谱。该连锁图谱包含19个连锁群,覆盖基因组长度为1 414.2 cM,标记间平均距离为10.2 cM。对结实花初花节位开展QTL分析,共检测到9个QTL,分别分布在第1、9、10、11连锁群上,各QTL的LOD值在2.89 ~ 9.42之间,4个QTL贡献率超过10%。位于第9连锁群的QTL Fp9.4贡献率最大,为18.57%(2010秋季LOD = 9.17);位于第9连锁群的Fp9.3(2010春季8.64%,LOD = 6.44;2010秋季17.99%,LOD = 9.42),位于第10连锁群的Fp10.1(2010春季3.59%,LOD = 2.89;2010秋季6.20%,LOD = 3.43)在两季的位置都很稳定。获得与结实花初花节位紧密连锁(< 10 cM)的8个特异标记(SSR01737、MU141991、TJ105、GCM206、SSR04910、MU173563、NR52、MU146331),为进一步开展QTL精细定位提供参考。 相似文献
29.
辣椒抗根结线虫基因Me3的精细定位 总被引:1,自引:0,他引:1
以含Me3基因的抗根结线虫辣椒自交系‘HDA149’为父本,感根结线虫辣椒自交系‘8214’为母本,构建了一个2 133株的F2作图群体。采用群体分离分析法(Bulked Segregant Analysis,BSA),构建抗、感病两个DNA池,对由两亲本筛选出来的285对引物进行扩增分析,发现引物SSCP_B322和EPMS658在抗、感池间具有稳定的多态性。继续用这两对引物对F2单株进行扩增,以JoinMap 3.0软件分析发现SSCP_B322和EPMS658标记位于Me3基因两侧,遗传图距分别为0.56 cM和1.33 cM。运用回交群体BC1和F3群体验证实了这两个标记,可有效用于辣椒抗线虫分子标记辅助育种,也为图位克隆Me3基因奠定了基础。 相似文献
30.