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1.
Plantlet regeneration via somatic embryogenesis in anther callus of Vitis latifolia L. 总被引:1,自引:0,他引:1
Anthers of Vitis latifolia L. (wild grape) cultured on Nitsch and Nitsch medium supplemented with 20 μM 2,4-D and 9 μM BAP produced callus after 4–6 weeks. Subculture of callus onto Nitsch and Nitsch medium containing 10 μM NAA produced somatic embryos within 6 weeks. On growth regulator-free Nitsch and Nitsch basal medium somatic embryos converted
to plantlets in 6–8 weeks. One gram of callus produced more than 400 somatic embryos with 13.7% being converted to complete
plantlets, which were subsequently established in soil. Regenerated plants were found to have mixoploid populations of cells,
2n = 38 and n = 19.
Received: 23 May 1998 / Revision received: 21 September 1998 / Accepted: 10 October 1998 相似文献
2.
E. G. Korvin-Pavlovskaya I. V. Neklyudova L. V. Beloussov 《Russian Journal of Developmental Biology》2006,37(2):77-84
Circumferential and radial components of the yolk cell surface movements were measured in the loach embryos at the late blastula stage within 40–50 min after puncture or indentation by an obliquely directed glass rod. The yolk cell surface was preliminarily marked by coal particles. It was shown that even closely located regions of the surface differed markedly in the rate and direction of their movements. In the vicinity of puncture, the yolk cell surface at first contracted in both circumferential and radial directions and then widened, but did not reach the initial values. In more remote areas, this surface continued to contract in the circumferential direction, but was extended in the radial direction. The degree of its contraction along different radii was unequal. The reaction to oblique indentation was anisotropic: the closest area of the yolk cell surface, located along the direction of indentation, contracted in both circumferential and radial directions and formed a fold “leaking” onto the rod, while the opposite area contracted in the circumferential direction, but extended in the radial direction. A conclusion was drawn that the yolk cell surface is a multivariant mechanosensitive system. Its active responses to mechanical influences obey the same patterns as multicellular embryonic tissues. 相似文献
3.
The effects of delayed mating on mouse preimplantation embryos (78 ± 1 hours) were studied by setting up different mating periods in relation to the estimated time of spontaneous ovulation. Copulation occurred even in the late morning and early afternoon after the night of spontaneous ovulation. However, females mated in the early afternoon had no viable embryos at the time of laparotomy. Although embryonic development was not affected in the groups mated 6 or 10 hours after estimated ovulation, the percentage of degenerated embryos was increased in these groups. These results suggest that prolonged intervals between the estimated time of ovulation and mating have some deleterious effects on preimplantation embryos. 相似文献
4.
For a distinct autochthonous Austrian coregonid population called Reinanke Coregonus sp., embryo viability was very low in Zuger jars (mean ± s.d. 36·1 ± 16·1% eyed stage embryos in experiment 1, 15·1 ± 17·0% in experiment 2) but high in vertical flow incubators (63·3 ± 29·0% eyed stage embryos in experiment 1, 57·8 ± 18·9% in experiment 2). Mechanical shock sensitivity is a possible explanation for high embryo mortality. 相似文献
5.
Bernard Pélissier Ouafa Bouchefra Régis Pépin Georges Freyssinet 《Plant cell reports》1990,9(1):47-50
We describe here a two step procedure which allows the easy isolation of somatic embryos from Sunflower (Helianthus annuus L.) hypocotyl tissues. Thin cell layers composed of the epidermis plus 3 to 6 parenchyma cell layers were incubated for 5 days in a basal Murashige and Skoog medium using an auxin to cytokinin weight ratio of 1/1. The epidermis layers were then transferred to a Gamborg medium containing a high level of sucrose. After one week of incubation in this medium, many somatic embryos started to be released from the parental epidermal tissue. Even though the germination of these embryos is difficult, we have been able to induce secondary embryos and regenerate fertile plants.Abbreviations NAA
1-naphthalene acetic acid
- IAA
indole-3-acetic acid
- BAP
6-benzylamino-purine
- MS
Murashige and Skoog medium
- B5
Gamborg medium 相似文献
6.
7.
Dr. Gordon C. Tucker Michel Delarue Suher Zada Jean-Claude Boucaut Jean Paul Thiery 《Cell and tissue research》1988,251(2):457-465
Summary A family of glycoconjugates has recently been shown to share a common carbohydrate epitope recognized by the mouse monoclonal antibody HNK-1. The specificity of HNK-1 was found to be similar to that of another monoclonal antibody, NC-1. These two IgM monoclonal antibodies were raised after immunization of mice with a human T-cell line and avian neural crest-derived ganglia, respectively. The antigens recognized by these antibodies include the myelin-associated glycoprotein, MAG, a glycolipid of defined structure, and a set of molecules involved in cell adhesion. The timing and pattern of appearance of these antigens are distinct. Moreover, the epitope may be absent on an antigen at a given stage or in a given tissue. Therefore, although the molecules able to carry the NC-1/ HNK-1 epitope are numerous and expressed in various tissues, the use of the monoclonal antibodies on tissue sections has proven adequate for following the migration of avian neural crest cells, the major cell lineage recognized by NC-1 and HNK-1 during early embryogenesis. Analogies in several other species have been found on the basis of HNK-1 reactivity. In this study we show that NC-1 and HNK-1 can be used successfully to label migrating neural crest cells in dog, pig and human. On the other hand, the NC-l/HNK-1 epitope was not present on migrating crest cells in amphibians or mice and was found only transiently on the neural crest of rats. 相似文献
8.
B. Witrzens W. R. Scowcroft R. W. Downes P. J. Larkin 《Plant Cell, Tissue and Organ Culture》1988,13(1):61-76
A method is described for the culture and regeneration of plants from callus of sunflower (Helianthus annuus) andH. annuus x H. tuberosus hybrids. Immature embryos proved to be the only explant which consistently gave regenerable cultures in all genotypes. The most responsive embryos were approximately 12 mm2 in area. Genotype had a significant effect on the capacity of cultures to regenerate. Some regeneration was also obtained from cultures of tuber tissue but only from one genotype,H. tuberosus x H. annuus cross 200. None of theH. annuus accessions gave regenerable callus from root tissue. Difficulties included the premature initiation of flowering of regenerating shoots and the frequent occurence of "vitreous" plantlets which could not be transplanted successfully to soil. Some amelioration of both these problems was achieved by replacing inorganic nitrogen partially with amino acids. More effective reduction of these difficulties was accomplished by the addition of 10, 30 and 100 M phloridzin, esculin or naringin.Abbreviations BAP
6-benzylaminopurine; zeatin, trans-6-(4-hydroxy-3-methyl-but-2-enyl) aminopurine; kinetin, 6-furfurylaminopurine
- IAA
indole-acetic acid
- NAA
naphthyl acetic acid 相似文献
9.
P. Bebeli A. Karp P. J. Kaltsikes 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1988,75(6):929-936
Summary Plants were regenerated from cultured immature embryos of two pairs of sister lines of triticale (X Triticosecale) cvs Rosner and Drira and five sister lines of rye (Secale cereale). The triticale lines differ in heterochromatic content of a particular rye chromosome (6R or 7R), while the rye lines differ in only one heterochromatic band. Variation in morphogenetic response was present between the triticale cultivars and between the rye lines. One of the rye lines (7RL+ +) showed a distinctive superior response in terms of somatic embryogenesis. These findings are discussed in relation to factors affecting morphogenetic response and genetic stability in culture. 相似文献
10.
Gerald M. Kidder Douglas J. Barron Joanna B. Olmsted 《Development genes and evolution》1988,197(2):110-114
Summary We have examined the persistence of midbody channels during the second, third, and fourth cleavage cycles of the mouse using immunofluorescence to map the distribution of midbody microtubule bundles in intact embryos. Electron microscopy showed these bundles to be a characteristic feature of midbodies throughout the interphase period. In recently-divided embryos at each cleavage stage the number of midbodies was half the number of blastomeres, and declined towards zero as the next cleavage approached. This indicated to us that the only midbodies present in each stage were those which had arisen in the immediately-preceding division. Of those blastomeres which were in mitosis at the time of fixation, less than 4% were connected via a midbody to another blastomere, demonstrating that persistence of midbodies beyond a single cleavage cycle is a rare event. We conclude that midbody channels in our embryos are likely to connect only pairs of sister blastomeres because midbodies do not persist through multiple cleavage cycles. Midbody channels cannot, therefore, be regarded as providing extensive cell coupling in advance of the onset of gap junctional communication. 相似文献