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41.
42.
N. V. Trubacheeva T. T. Efremova E. D. Badaeva L. A. Kravtsova L. I. Belova E. P. Devyatkina L. A. Pershina 《Russian Journal of Genetics》2009,45(12):1438-1443
Alloplasmic lines of common wheat with disomic substitution of chromosome 7D for telocentric chromosome 7H1Lmar of barley H. marinum subsp. gussoneanum Hudson were isolated from the plants of generation BC3, produced as a result of backcrossing of barley-wheat hybrids H. marinum subsp. gussoneanum (2n = 28) × T. aestivum (2n = 42), Pyrotrix, cultivar, with 28 common wheat cultivars Pyrotrix 28 and Novosibirskaya 67. Chromosome substitution pattern
was determined using SSR analysis and C-banding. In preliminary genomic in situ hybridization experiments, telocentric chromosomes
were assigned to wild barley was established. In the BC3F8 generations of three alloplasmic lines with the 7H1Lmar(7D) substitution type the differences in fertility manifestation were observed: most of the L-32(1) plants were sterile,
in line L-32(2) only sporadic plants were sterile, and line L-32(3) was fertile. Simultaneously with these experiments, using
selfpollinated progeny of the hybrids obtained in crosses of common wheat cultivar Saratovskaya 29 (2n = 41), monosomic for chromosome 7D, with common wheat cultivar Pyrotrix 28 with addition of pair of telocentric chromosomes
7H1Lmar (7D) of barley H. marinum subsp. gussoneanum, euplasmic wheat-barley ditelosomic substitution 7H1Lmar (7D) lines were isolated. The lines obtained had normal fertility. PCR analysis of the 18S/5S mitochondrial repeat (hereafter,
mtDNA sequence) in alloplasmic and euplasmic ditelosomic substitution lines 7H1Lmar(7D) was performed. In the plants from alloplasmic sterile line L-32(1), the sequences only of the barley (maternal) type
were revealed, while the plants from alloplasmic fertile lines L-32(2) and L-32(3) demonstrated heteroplasmy (the presence
of barley- and wheat-like sequences within one individual). In euplasmic ditelosomic substitution lines the presence of only
wheat-like 18S/5S mitochondrial repeat sequences was observed. The results indicate that the presence of barley-like mtDNA
sequences in alloplasmic substitution lines was not associated with the presence of barley chromosomes in their nuclear genomes. 相似文献
43.
Body condition‐dependent dispersal strategies are common in nature. Although it is obvious that environmental constraints may induce a positive relationship between body condition and dispersal, it is not clear whether positive body conditional dispersal strategies may evolve as a strategy in metapopulations. We have developed an individual‐based simulation model to investigate how body condition–dispersal reaction norms evolve in metapopulations that are characterized by different levels of environmental stochasticity and dispersal mortality. In the model, body condition is related to fecundity and determined either by environmental conditions during juvenile development (adult dispersal) or by those experienced by the mother (natal dispersal). Evolutionarily stable reaction norms strongly depend on metapopulation conditions: positive body condition dependency of dispersal evolved in metapopulation conditions with low levels of dispersal mortality and high levels of environmental stochasticity. Negative body condition‐dependent dispersal evolved in metapopulations with high dispersal mortality and low environmental stochasticity. The latter strategy is responsible for higher dispersal rates under kin competition when dispersal decisions are based on body condition reached at the adult life stage. The evolution of both positive and negative body condition‐dependent dispersal strategies is consequently likely in metapopulations and depends on the prevalent environmental conditions. 相似文献
44.
45.
N. V. Trubacheeva L. P. Rosseeva I. A. Belan T. S. Osadchaya L. A. Kravtsova Yu. V. Kolmakov N. P. Blokhina L. A. Pershina 《Russian Journal of Genetics》2011,47(1):13-18
Using genomic in situ hybidization, among the common wheat cultivars produced in West Siberia (Siberian Research Institute
of Agriculture, Omsk) with the involvement of the winter wheat cultivar Kavkaz carrying the wheat-rye 1RS.1BL translocation
we identified three cultivars with this translocation: Omskaya 29, Omskaya 37, and Omskaya 38. The protein and crude gluten
contents in the grain of these cultivars are equal to or exceed the levels observed in cultivars without the wheat-rye translocation.
The common wheat cultivars carrying the wheat-rye translocation were evaluated in terms of resistance of plants reaching wax
ripeness to leaf rust and powdery mildew in the natural field conditions. The cultivars Omskaya 37 and Omskaya 38 displayed
a high field resistance to leaf rust and were resistant to a variable extent to powdery mildew. The cultivar Omskaya 29 was
susceptible to leaf rust and powdery mildew pathogens. Importance of the selection direction and the role of the genetic background
in developing common wheat cultivars carrying the wheat-rye translocation is discussed. 相似文献
46.
47.
Pershina LA Belova LI Deviatkina EP Rakovtseva TS Kravtsova LA Shchapova AI 《Genetika》2005,41(6):784-792
The role of individual chromosomes of rye in the manifestation of crossability and seedling development in hybrid combinations between common barley Hordeum vulgare L., cultivar Nepolegayushchii (2n = 14) and five wheat-rye substitution lines Triticum aestivum L., cultivar Saratovskaya 29/Secale cereale L., cultivar Onokhoiskaya (2n = 40 wheat + 2 rye chromosomes). Crossability, which was measured by two parameters--frequency of set grains and frequency of grains with embryos--was shown to be significantly affected by each of the five rye chromosomes examined: 1R, 2R, 3R, 5R, and 6R; the development of barley haploids was affected by rye chromosomes 1 R, 3R, and 5R. We were the first to demonstrate that polyembryony could be induced by mutual effects of barley cytoplasm and rye chromosome 1R. Possible mechanisms controlling the development of haploids and twins in hybrid combinations H. vulgare x T. aestivum/S. cereale are discussed. The conclusion is drawn that hybrid combinations between common barley and wheat-rye substitution lines can serve as new models for studying incompatibility mechanisms in distant crosses and genetic control of parthenogenesis. 相似文献
48.
49.
50.
Lipoteichoic acid is an important microbe-associated molecular pattern of Lactobacillus rhamnosus GG
Claes Ingmar JJ Segers Marijke E Verhoeven Tine LA Dusselier Michiel Sels Bert F De Keersmaecker Sigrid CJ Vanderleyden Jos Lebeer Sarah 《Microbial cell factories》2012,11(1):1-8