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41.
ZHENG YongqiResearch Institute of Forestry. Chinese Academy of Forestry. Beijing 《中国林业科技(英文版)》2002,(1)
Family outcrossing rates of Pinus caribaea var. caribaea populations that differed in origin and management were estimated by using isozyme markers. The family outcrossing rates were estimated by (1)fixing the probability of pollen gene frequency (p); (2) allowing pollen gene frequency to vary among families. The estimates of family outcrossing rates for all the populations varied widely among families (clones of the seed orchard), ranging from 0.39 to 2.0. The average family outcrossing rates of both methods were greater than the 相似文献
42.
利用EST同工酶谱鉴定黑稻品种纯度的研究 总被引:1,自引:0,他引:1
采用改进的聚丙烯酰胺凝胶电泳对5种黑稻主要栽培品种进行了EST同工酶谱分析.结果表明,此方法分辨率高.测试各品种的EST同工酶存在丰富的多态性,其电泳图谱具有鲜明的特征,并构成了各自的"指纹".其中黑优粘和云黑酶谱条带数多达15条,a1和a3为5个品种的共有谱带.通过EST同工酶谱相似度指数分析,黑优粘与黑丰糯、乌贡1号相似度指数大于0.75,说明这3个品种间亲缘关系较近. 相似文献
43.
44.
Summary Polymorphism of ten enzymes, acid phosphatase (APH), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), phosphorylase (PP), superoxide dismutase (SOD), malic enzyme (ME), glutamate oxaloacetate transaminase 1 and 2 (GOT-1, GOT-2) and phosphoglucomutase 1 and 2 (PGM-1 and PGM-2), was investigated in three gene pools of cultivated chicory, including six cultivated wild chccory, eight industrial chicory and eight Brussels chicory varieties. LAP, APH, PP and PGM-2 showed high phenotypic polymorphism whilst GOT-1 and ME had poor polymorphism. For three enzyme coding loci Lap, Pgm-1 and Got-2, allele frequencies were determined. Isozyme composition in the three chicory gene pools was significantly different, showing, respectively, high, intermediate and poor average amount of phenotypic polymorphism in cultivated wild chicory, industrial chicory and Brussels chicory. Isozyme variation within and between varieties of the three gene pools is discussed in relation to breeding practices. 相似文献
45.
Summary Six Festuca rubra populations from Europe and Scandinavia were studied for variation at three isozyme loci; phosphoglucoisomerase (PGI-2), glutamate oxaloacetate transaminase (GOT-3) and superoxide dismutase (SOD-1). Seven alleles were found at the Pgi-2 locus, four at the Got-3 locus and five at the Sod-1 locus. Most plants were heterozygous and up to five alleles were found in the same plant at the Pgi-2 locus. Each population could be distinguished by the presence or absence of certain alleles or by differences in the frequencies of the alleles present. Values for the Shannon diversity index were calculated which showed that there was considerable heterogeneity both within and between loci. In general, 53% of this diversity could be attributed to within population variation. 相似文献
46.
Some characteristics of the species complex Pennisetum section Brevivalvula are polyploidy and apomixis. Four euploidy levels
(x = 9) were assessed by DAPI-flow cytometry for 304 plants of the section, distributed among five species: P. hordeoides
(2n = 36, 54), P. pedicellatum (2n = 36, 45, 54), P. polystachion (2n = 18, 36, 45, 54), P. setosum (2n = 54), and P. subangustum
(2n = 18, 36, 54). The geographical distribution of the ploidy levels seems to be related to major ecological zones of West
Africa. The hilly regions displayed a higher ploidy diversity than the others; diploid populations of the annual species P.
polystachion and P. subangustum were found. Genotypic variation expressed by isozyme polymorphism did not show any significant
difference between the diploid, sexual populations and the polyploid, apomictic populations of these two species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
47.
Summary Electrophoretic variants of peroxidase in mulberry (Morus spp.) were demonstrated by thin-layer gel isoelectric focusing. Of these variants, three isozyme band groups were found to be controlled by codominant alleles at a single locus. The gene symbol Px
1 was given to this locus, with alleles Px
1
1 and Px
1
2 assigned to the A6-A7-A8 and A7-A8-A9 band groups, respectively. The A6-A7-A8-A9 band group proved to be controlled by the Px
1
1 and Px
1
2 heterozygote.Additional experiments showed that among the three banding types, there were no statistically significant differences in leaf blade length, leaf blade width, length-width ratio of leaf blade, internode length, phyllotaxis, leaf shape, tree vigor and resistance to powdery mildew, but there were significant differences in leafstalk length. 相似文献
48.
Summary We have succeeded in producing useful interspecific hybrid using ovule-embryo culture between Gypsophila paniculata L. Red Sea and G. manginii, an incompatible combination by ordinary cross breeding methods. The hybrid plant had double flowers with a color of pale purplish pink. Hybrid characteristics of the plant were firmed by observation of plant form, flower type, chromosome number and peroxidase isozyme patterns. 相似文献
49.
Summary The segregation of 12 heterozygous isozyme markers was analyzed among F2 plants and 51 anther culture (AC)-derived lines obtained from the japonica × indica cross of rice, IRAT 177 × Apura. All the lines except two were homozygous products of recombination of the two parental phenotypes. Doubled haploid (DH) lines derived from plants regenerated from the same callus were identical, confirming previously obtained results in rice. Surprisingly, some lines derived from different calli were also identical, suggesting a phenomenon of early callus fragmentation. All these observations at the isozyme level were confirmed by field evaluation. Deviations of segregations from the expected 1 : 1 ratio were observed at 4 loci among the DH lines. Among these, two were also noted among the F2 plants. The two other distortions, both in favor of the japonica allele, were observed specifically in the AC-derived materials.Although this concerns a small proportion of the genes under study, it suggests that the embryogenic microsporal population does not represent a random gametic array. On the other hand, evaluation of recombination between isozyme genes located on chromosome 6 appears consistent with F2 data and data previously recorded on the other japonica × indica crosses. The potential use of isozymes in breeding doubled haploids derived from remote crosses in rice is discussed.Abbreviations MCPA =
2-methyl-4-chlorophenoxyacetic acid
- IAA =
indolacetic acid
- AC plant or line =
anther culture-derived plant or line
- DH line =
doubled haploid line 相似文献
50.
Summary We report on the inheritance of 11 morphological markers and 17 isozymes in lentil (Lens culinaris). The monogenic inheritance of 11 morphological markers and 11 isozymes is confirmed. The inheritance of six isozymes (Aco-2, Enp, Est-3, Est-4, Lap-3, and Mdh-m) is reported for the first time in lentil. This brings the total number of described genes in lentil to 78. Cases of disturbed segregation were more frequent than expected by chance. It is suggested that disturbed segregation was in most cases caused by linkage with a piece of chromosome that showed preferential elimination in crosses between Lens culinaris ssp. odemensis and other subspecies. The prevalence of disturbed segregation in crosses with Lens culinaris ssp. odemensis could limit the usefulness of this subspecies in genetic and linkage studies. 相似文献