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131.
Sosnikhina S. P. Kirillova G. A. Tikholiz O. A. Mikhailova E. I. Priyatkina S. N. Smirnov V. G. 《Russian Journal of Genetics》2002,38(3):269-276
Partially nonhomologous (heterologous) synapsis of meiotic chromosomes in a spontaneous desynaptic mutant form of rye is determined by two recessive genes, sy2a and sy2b, that have independent expression and inheritance. The third gene, dominant inhibitor suppressing the mutant phenotype, has been revealed in hybrid combinations between sy2 mutants and lines segregating other meiotic mutants: sy10 (heterologous synapsis), sy1, and sy9(asynapsis). All three genes determining desynapsis (sy2a, sy2b, and I) were shown to be nonallelic to monogenic mutations sy10, sy1, and sy9, inherited independently of them and expressed at later stages of prophase I than the sy10 gene. The possibility of modifying monogenic segregation of mutation sy2 by gametophyte selection for a locus linked to the gene expressed as sy2 at particular frequencies of recombination between this gene and selected locus is discussed. 相似文献
132.
S. P. Sosnikhina G. A. Kirillova E. I. Mikhailova O. A. Tikholiz V. G. Smirnov Yu. S. Fedotova O. L. Kolomiets Yu. F. Bogdanov 《Russian Journal of Genetics》2001,37(1):71-79
Analysis of manifestation and inheritance of a new mutation inducing irregular synapsis in rye showed that abnormal phenotype is determined by a recessive allele of the sy19 gene. In the homozygotes for this mutation, even at the light microscopic level, abnormal formation of bivalents is already observed at pachytene–diakinesis. At metaphase I, the univalent frequency varies from 0 to 14; in a few cells, multivalent associations of chromosomes, which are not clearly oriented in the spindle, are detected. Electron microscopy of synaptonemal complexes revealed both homologous and heterologous synapsis in homozygotes for sy19, namely partial loss of the ability to stringent homology search. Analysis of joint inheritance of sy19 and asynaptic sy1 mutations showed that they are nonallelic, inherited independently, and interact by recessive epistasis. The phenotype of doublesy1sy19 mutants indicates that thesy19 gene conditioning heterologous synapsis operates at meiosis later than the synaptic gene sy1. The epistatic group of mutations, sy9 > sy1 > sy19 and sy3, was determined. 相似文献
133.
V. V. Aleksandrov A. V. Branitskii G. S. Volkov E. V. Grabovskii M. V. Zurin S. L. Nedoseev G. M. Oleinik A. A. Samokhin P. V. Sasorov V. P. Smirnov M. V. Fedulov I. N. Frolov 《Plasma Physics Reports》2001,27(2):89-109
Prolonged plasma creation in heterogeneous liners, in which the liner substance is separated into two phase states (a hot plasma and a cold skeleton), is investigated both experimentally and theoretically. This situation is typical of multiwire, foam, and even gas liners in high-current high-voltage facilities. The main mechanisms governing the rate at which the plasma is created are investigated, and the simplest estimates of the creation rate are presented. It is found that, during prolonged plasma creation, the electric current flows through the entire cross section of the produced plasma shell, whose thickness is comparable with the liner radius; in other words, a current skin layer does not form. During compression, such a shell is fairly stable because of its relatively high resilience. It is shown that, under certain conditions, even a thick plasma shell can be highly compressed toward the discharge axis. A simplified numerical simulation of the compression of a plasma shell in a liner with prolonged plasma creation is employed in order to determine the conditions for achieving regimes of fairly compact and relatively stable radial compression of the shell. 相似文献
134.
I/D polymorphism in the angiotensin-converting enzyme gene in men with myocardial infarction at young age] 总被引:1,自引:0,他引:1
O A Berkovich E A Bazhenova E A Volkova M Z Alugishvili I O Kiselev B I Smirnov E I Shvarts E V Shliakhto 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2001,87(5):642-648
The rate of D allele did not differ between patients with ischemic heart disease (IHD) who had myocardial infarction before the age 45, and healthy males. The DD genotype of the ACE gene was much more frequently encountered in the patients than in healthy males. The findings suggest that the DD genotype is an independent risk factor of the IHD and myocardial infarction in young patients. 相似文献
135.
The mitotic indices, villus heights, and crypt depths were determined in each of three jejunal regions (proximal, middle, and distal) for five animals each in the flight, vivarium, and synchronous groups. Because of the rapid turnover of intestinal mucosal cells and the delay in recovering the flight animals, it is not known whether the proliferation of jejunal mucosal cells is affected by microgravity conditions associated with spaceflight. However, since there were no consistent differences between animals in the flight group and those in the synchronous and vivarium control groups, it appears that any effects of microgravity on the turnover of jejunal mucosal cells are short-lived. Thus, this study represents an initial step in determining the effects of microgravity on the proliferation and turnover of intestinal mucosal cells. 相似文献
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Four mutations were studied which lead to increasing the frequency of transposon Tn1 translocation into different replicons. These mutations (het1, het2, het3 and het4) increase the frequency of Tn1 translocation 10-20-fold. The het1 mutation is recessive and has been localized in the 90-94.5 min region of the bacterial chromosome. The mutation effects Tn1 transposition in the presence of F plasmid only. As we have demonstrated recently, F-plasmid inhibits Tn1 transposition in Escherichia coli cells. The het1 mutation eliminates this inhibition. Unlike het2, het3 and het4 mutations, het1 is responsible for resistance to male phages f1, f2, MS2 and inhibition of conjugative transfer in F+ bacteria. 相似文献
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140.
G A Kochetkov S G Smirnov S Ia Savranskaia I M Gruber 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1977,(9):123-127
The content of trace elements in the cells served as one of the characteristics of physiological condition of the population. The character of the changes in the trace elements content depending on the rate of the microbial multiplication pointed to the importance of the mineral sources of nutrition for the development of the cells analyzed. 相似文献