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31.
32.
贵州白山羊GDF9基因外显子2的多态性研究 总被引:2,自引:1,他引:1
生长分化因子9(GDF9)是卵母细胞分泌的生长因子,对早期卵泡的生长和分化起重要的调节作用。采用RFLP和SSCP方法检测贵州白山羊GDF9基因外显子2的单核苷酸多态性,结果表明:在所有检测样本中均未发现GDF9基因的FecGH突变;在高繁殖率(3羔以上/胎)母羊和公羊中检测到8个杂合的AB基因型,其中5个为高产的母羊,3个为公羊。碱基序列分析证实GDF9基因编码区第1189bp位点的碱基由G突变为A,该位点位于外显子2中,导致活性肽第79位缬氨酸突变为异亮氨酸(V79I),但在低繁殖率(1~2羔/胎)母羊中没有发现该突变。虽然贵州白山羊GDF9基因中G1189A突变的发生率仅为5%,但该位点编码的氨基酸与FecGH突变(S77F)仅相隔1个氨基酸,因此推测GDF9基因中的G1189A突变可能与贵州白山羊的高繁殖力有关。 相似文献
33.
大豆品种间DNA限制性片段长度多态性(RFLP)的分析 总被引:5,自引:0,他引:5
用62个大豆DNA分子探针与5种限制性内切酶组合,对大豆基因组DNA限制性片段长度多态性(RFLP)进行分析,结果表明,所选用的两对材料,其多态性RFLP标记的频率均高达60%,可作为RFLP作图较理想的亲本,RFLP标记的多态性类型表现为共显性,少数为显性,其中一些标记揭示了2个或2个以上的独立分离的基因座位,不同限制性内切酶的揭示多态性的能力上差异不显著,在杂交片段长度上差异显著并都大于预期, 相似文献
34.
Assessment of genetic diversity of cultivated chickpea using microsatellite-derived RFLP markers: Implications for origin 总被引:2,自引:0,他引:2
Restriction fragment length polymorphism (RFLP) analysis was performed on 30 accessions of cultivated chickpea (Cicer arietinum L.) collected from 11 different countries representing the Near East, Central Asian and Hindustani regions. A synthetic digoxygenated oligonucleotide (GATA)4 complementary to a microsatellite DNA sequence was used as a probe. The results revealed that simple repetitive sequences are abundant and polymorphic in the chickpea genome. The fragments detected were used lo estimate the genetic diversity within accessions and a similarity index between the genotypes of the accessions. The genetic distance data were used to construct a dendrogram depicting genetic relationships among the different accessions. The results indicate that the greatest genetic diversity occurs in Pakistan, Iraq, Afghanistan, south-east Russia, Turkey and Lebanon. Lower genetic diversity was found in Iran, India, Syria, Jordan and Palestine, Based on DNA markers, it is concluded that there are three centres of diversity for chickpea: Pakistan-Afghanistan. Iraq Turkey and Lebanon. India, which was previously considered as a secondary center of diversity for chickpea, showed lower diversity than the above regions. 相似文献
35.
畜禽DNA指纹的研究与应用 总被引:9,自引:3,他引:6
综述了DNA指纹技术的原理,方法,以及在个体(品种)鉴别,亲缘关系分析,群体遗传变异分析,连锁分析等方面的研究进展。 相似文献
36.
长江水系中华绒螯蟹线粒体DNA的遗传多样性研究 总被引:3,自引:0,他引:3
本文对长江水系南京和江都地区中华绒螯蟹共61个个体的线粒体COI基因进行了限制性片段长度多态性(RFLP)分析。应用PCR技术扩增了中华绒螯蟹线粒体COI基因,选用8种能识别4碱基的限制性内切酶对该基因片段进行RFLP分析。在两个群体中共检测出8种复合单倍型,其中复合单倍型AAAAAAAA和BBBBBAAB为两个群体所共有,它的个体数所占的百分比在两个群体(南京和江都)中分别为87.9%、12.1%和50.0%、25.0%。在南京群体中,复合单倍型间的遗传距离为0.077,而在江都群体中,复合单倍型间的遗传距离为0.004~0.077;南京和江都群体的线粒体COI基因多态度(或称核苷酸多样性指数)π值分别为0.008和0.019。结果说明长江水系中华绒螯蟹具有一定的群体内遗传多样性。 相似文献
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39.
Molecular mapping of an aluminum tolerance locus on chromosome 4D of Chinese Spring wheat 总被引:13,自引:0,他引:13
Summary The tolerance of aluminum (Al) of disomic substitution lines having the chromosomes of the D genome of Triticum aestivum L. cv. Chinese Spring individually substituted for their homoeologues in T. turgidum L. cv. Langdon was investigated by the hematoxylin method. The disomic substitution lines involving chromosome 4D were more Al tolerant than Langdon. The tolerance was found to be controlled by a single dominant gene, designated Alt2, that is in the proximal region of the long arm of chromosome 4D. The locus was mapped relative to molecular markers utilizing a population of recombinant chromosomes from homoeologous recombination between Chinese Spring chromosome 4D and T. turgidum chromosome 4B. Comparison of the location of Alt2 in this map with a consensus map of chromosomes 4B and 4D based on homologous recombination indicated that Alt2 is in a vicinity of a 4 cM interval delineated by markers Xpsr914 and Xpsr1051. The Alt2 locus is distal to marker Xpsr39 and proximal to XksuC2. The Altw locus is also proximal to the Knal locus on chromosome 4D that controls K+/Na+ selectivity and salt tolerance. In two lines, Alt 2 and Knal were transferred on a single 4D segment into the long arm of T. turgidum chromosome 4B. 相似文献
40.
M. J. gilpin R. A. pickering A. G. fautrier D. L. mcneil G. szigat A. M. Hill R. G. Kynast 《Plant Breeding》1997,116(6):505-510
Anther culture (AC) was carried out on a fertile triploid hybrid between Hordeum vulgare L. (cultivated barley) and H. bulbosum L, (bulbous barley grass) to determine whether AC-derived regenerants differed from progeny obtained through selfing and backcrossing. Chromosome counts were carried out on all plants and DNA was extracted from them to prepare Southern blots for molecular analysis. To identify true recombinants, the blots were probed with rye repetitive sequence probes (pSc119.1 and pScl19.2). which hybridize strongly and specifically to H. bulbosum DNA. Twenty probes that detect single- or low-copy sequences were hybridized with Southern blots containing restricted DNA extracted from 25 AC-derived plants, 11 selfed and six backcrossed progeny that showed hybridizations with pScll9. Although restriction fragment length polymorphisms (RFLPs) were only observed using probes that map to four of the possible 14 chromosome arms, an introgression associated with chromosome 6HS was frequently observed among plants derived from AC. selfing and backcrossing. Plants from AC differed from selfed and backcrossed progeny in their chromosome number; unique RFLP bands that were occasionally observed may indicate chromosomal rearrangements. 相似文献