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621.
622.
两种非放射性标记方法在染色体原位杂交中敏感性的比较 总被引:1,自引:0,他引:1
通过原位杂交比较了地高辛配基和生物素标记探针,检测染色体单拷贝基因的敏感性。结果表明:在打点检测条上地高辛配基可检出30fg低限探针DNA,生物素为1pg。经原位杂交地高辛配基可检测出单拷贝基因,生物素未成功。 相似文献
623.
Yoshikane Iwatsubo Naohiro Naruhashi Heinrich E. Weber 《Plant Systematics and Evolution》1995,198(1-2):143-149
Chromosome numbers are presented for 32 collections of 29 European blackberry species (Rubus subg.Rubus) from Germany. One species is triploid (2n = 21), 27 species are tetraploid, (2n = 28), and one species is pentaploid (2n = 35). Chromosome numbers are reported for the first time ofR. adspersus, R. amisiensis, R. calvus, R. conothyrsoides, R. contractipes, R. demissus, R. elegantispinosus, R. ferocior, R. foliosus, R. hypomalacus, R. leucandrus, R. nemorosus, R. platyacanthus, R. praecox, R. rhombifolius, andR. rhytidophyllus. Chromosome numbers forR. dasyphyllus, R. gelertii, R. glandithyrsos, R. lamprocaulos, R. lindebergii, R. macrophyllus, R. montanus, R. muenteri, R. pedemontanus, R. polyanthemus, R. senticosus, R. silvaticus, andR. vigorosus are confirmed. 相似文献
624.
625.
Michele Flatters Rebecca Maxfield Dean Dawson 《Molecular & general genetics : MGG》1995,249(3):309-316
Meiotic chromosome segregation must occur with high fidelity in order to prevent the generation of aneuploid cells. We have previously described the identification and genetic characterization of a yeast mutant with defects in meiotic sister-chromatid segregation. We attributed the phenotype in this mutant to a dominant allele, which we referred to as SID1-1. These mutants appeared to exhibit high levels of nondisjunction and precocious separation of sister-chromatids of chromosome III, as well as precocious separation of sister chromatids of chromosome VIII and a univalent artificial chromosome. We show here that the unusual meiotic behavior of chromosome III in these strains is due to the presence of a ring III chromosome, rather than a mutant gene. Additional experiments demonstrate that a ring III/rod III pair alters the meiotic segregation of a univalent artificial chromosome. 相似文献
626.
A. Cavallini S. Baroncelli B. Lercari G. Cionini M. Rocca F. D'Amato 《Protoplasma》1995,186(1-2):57-62
Summary The first foliage leaf ofTriticum durum Desf., cvs. Capelli and Creso, was studied for the action of light and gibberellic acid on different aspects of plant growth. Creso is a short-strawed cultivar carrying theRht 1 gene, that influences both plant height and sensitivity to applied gibberellins. In this study, a cytophotometric analysis of chromosome endoreduplication in bulliform cells of the leaf epidermis was undertaken. The bulliform cells are arranged in long rows and comprise 4C, 8C, and 16C cells. The relative percentage of these cells was recorded under different light regimes and in the presence or absence of gibberellic acid (GA3). Our data indicate that light strongly affects the occurrence of chromosome endoreduplication. Although cvs. Cappelli and Creso show the same frequency of endo-reduplicated cells in the dark, all light treatments induce lower endo-polyploidy in cv. Creso whereas, in cv. Cappelli, a reduction in endo-polyploidy is observed when plants are irradiated with blue-lacking lights. This indicates that the action of a blue-light responsive photo-receptor determines high endopolyploidy. With respect to GA3 treatment, cv. Creso is again shown to be insensitive to hormone application, whereas in cv. Cappelli, gibberellic acid influences endopolyploidy level in the dark, causing very high frequencies of 8C cells and relatively high frequencies of 16C cells.This paper is dedicated to the memory of Sergio Baroncelli, Professor of Plant Breeding at the University of Pisa. 相似文献
627.
S. Taketa J. Kato K. Takeda 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(8):1203-1209
Four bread wheat (Triticum aestivum L.) cultivars, Aobakomugi, Chinese Spring, Norin 61 and Shinchunaga, were pollinated with five barley lines/cultivars consisting of three cultivated barley (Hordeum vulgare L.) lines, Betzes, Kinai 5 and OHL089, and two wild barley (Hordeum spontaneum C. Koch) lines, OUH602 and OUH324. Crossability, expressed as the percentage of embryo formation, varied from 0 to 55.4% among the cross combinations. The two wild barley lines generally had a higher crossability than the previously reported best pollinator, Betzes, and some Japanese wheat cultivars were better as the female parent than Chinese Spring. Ninety four hybrid plants were obtained from 250 embryos cultured, and their somatic chromosome numbers ranged from 21 to 36. Eighteen plants were mosaic in chromosome number. Twenty one-chromosome plants appeared most frequently (45.7%) followed by 28-chromosome plants (14.9%). C-banding analysis revealed that elimination of barley chromosomes was mainly responsible for the occurrence of aneuploid plants. In hypoploids derived from Betzes-crosses, chromosome 5 was preferentially eliminated as previously reported, while in hypoploids derived from OUH602-crosses, chromosome 4 was preferentially eliminated. The wild barley line OUH602 may be a useful parent for producing a new wheat-barley addition set because of its high crossability with wheat and a different pattern of chromosome elimination. 相似文献
628.
我国畲族总人口约66万,主要分布在福建、浙江等省,其中福建有36万人,宁德地区占17万人。我国已对20多个民族的PTC尝味能力进行了调查,其中包括浙江畲族〔1〕,但福建畲族未见报道。我们用阈值法〔2〕测定宁德地区民族中学学生的苯硫脲味盲频率,其中畲族... 相似文献
629.
The SPP1 connection 总被引:3,自引:0,他引:3
Paulo Tavares Anja Dröge Rudi Lurz Inge Graeber Elena Orlova Prakash Dube Marin van Heel 《FEMS microbiology reviews》1995,17(1-2):47-56
Abstract: The connector of the virulent Bacillus subtilis bacteriophage SPP1 (Styloviridae) is a structure localized at the phage head vertex which attaches the tail. It is formed by oligomerization of SPP1 gene product 6 (gp6; portal protein). The purified protein is found in solution essentially as a homo-tredecamer. Its assembly pattern resembles the turbine-like organization found for other portal proteins and has a defined handedness (Dube et al. (1993) EMBO J. 12, 1303–1309). A preliminary reconstruction of the structure shows that gp6 is composed of a lower ring connected by a narrow region to the upper area consisting of 13 lobes radiating from an inner ring. The assembly is organized around a central channel which spans its full height. A functional characterization of gp6 mutants showed that substitutions of defined amino acids by more basic residues lead to packaging of reduced amounts of DNA into the phage head (Tavares et al. (1992) J. Mol. Biol. 225, 81–92). Since SPP1 encapsidates its DNA by a headful mechanism, these mutations ( siz ) affect most probably a function on the headful sensor—signal transduction—headful cut system. Combination of siz alleles has severe effects in packaging. The resulting gp6 versions lead to the encapsidation of shorter DNA molecules at a lower efficiency than single siz mutants. Gene 6 is expressed late during SPP1 infection. Interestingly, the mass of portal protein inside the cell then increases continuously until lysis, reaching a level several fold higher than the amount required to accomplish its role as a structural component of the virion. 相似文献
630.
普通小麦与冰草间杂种的细胞遗传学及其自交可育性 总被引:12,自引:2,他引:10
为了进一步研究冰草属(Agropyron Gaertn.)的P染色体组与小麦染色体组间的遗传关系和评价P染色体组在属间杂种自交可育性上的遗传效应,获得了普通小麦品种Fukuho(Triticum aestivum cv.Fukuho,2n=42;AABBDD)与3个不同来源的四倍体冰草(A.cristatum<L.>Gaertn.,2n=28;PPPP)间的杂种(2n=35;ABDPP)。结果表明 相似文献