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21.
We ran a comparative analysis of storage proteins (gliadins, high(HMW) and low-molecularweight (LMW) glutenins, puroindolines, and exogenous pest alpha-amylase inhibitors) in the Saratovskaya 29 cultivar line from the collection of a genetic engineering laboratory, its parental forms (Albidum 24 and Lutescens 55/11), and distant ancestors (Poltavka, Selivanovskiy Rusak, Sarroza, and tetraploid Beloturka). It was confirmed that the allelic states of storage proteins in the Gli-1, Gli-2 and Glu-1 loci originate from ancestral forms from the collection of the Vavilov Institute of Plant Industry. Moreover, new alleles were found in Lutescens 55/11 (Glu-A1a) and Selivanovskiy Rusak (Glu-B1b) cultivars from the collection of the Institute of Cytology and Genetics. A new allelic state, Ha, was observed in the loci of the Poltavka cultivar as a soft-grain cultivar, and the ha allele was found in the hard-grain Albidum 24 and Sarroza cultivars. It was found that the expression rate of exogenous pest alpha-amylase inhibitors in the Saratovskaya 29 cultivar line is lower than that of ancestral cultivars (Albidum 24, Sarroza, Poltavka, and Beloturka). Such inhibitors are absent in the paternal form Lutescens 55/11. A high expression rate of protein pest inhibitors for exogenous α-amylases and puroindolines was observed in the Poltavka cultivar. The allelic composition of Glu-1 loci was newly studied in the Sarroza cultivar, which has some promising features. The Saratovskaya 29 cultivar line, on the basis of which a wide range of diverse lines were created in the Institute of Cytology and Genetics, is isogenic for all of the studied traits.  相似文献   
22.
A large-scale study of short retroposon (SINE) B1 has been conducted in the genome of rodents from most of the known families of this mammalian order. The B1 nucleotide sequences of rodents from different families exhibited a number of characteristic features including substitutions, deletions, and tandem duplications. Comparing the distribution of these features among the rodent families, the currently discussed phylogenetic relationships were tested. The results of analysis indicated (1) an early divergence of Sciuridae and related families (Aplodontidae and Gliridae) from the other rodents; (2) a possible subsequent divergence of beavers (Castoridae); (3) a monophyletic origin of the group Hystricognathi, which includes several families, such as porcupines (Hystricidae) and guinea pigs (Caviidae); (4) a possible monophyletic origin of the group formed by the remaining families, including six families of mouselike rodents (Myodonta). Various approaches to the use of short retroposons for phylogenetic studies are discussed.  相似文献   
23.
The frequency characteristics and cytological picture of cytomixis in the course of male meiosis are described in transgenic tobacco plants (Nicotiana tabacum L.) with altered flower morphology and male sterility. Effects of cytomixis on qualitative composition of meiotic products are studied (formation of cytoplasts and polyads). Doubling of the chromosome number was established to increase frequency of cytomixis in the studied plants.  相似文献   
24.
The cortical actinin contents was found to be higher in the inner medulla of the rat kidney. Tropomyosin was distributed differently: it is lower in the cortex than in outer or inner medulla. The processes controlled by these proteins seem to be important for the vasopressin renal effects, and the irregular distribution of these proteins reflects participation of different renal areas in facultative water reabsorption.  相似文献   
25.
The distribution of alleles and haplotypes of three diallellic Y-specific loci (YAP, DYF155S2, and Tat) in the populations of Kyrgyz, Uzbeks and Tajiks was analyzed. In Kyrgyzes and Uzbeks, a relatively high frequency of the DYF155S2 deletion (20 and 12.5%, respectively) and the C allele at the Tat locus (11.2 and 8.3%, respectively) were revealed. In the populations of southern Kyrgyzes and Uzbeks, two chromosomes carrying the YAP+ allele were detected. In both cases the YAP+ allele was found within the YAP+/DYF155S2+/TatT haplotype. The Tajik population was monomorphic in respect to the polymorphisms studied. The Tajiks demonstrated the presence of only the YAP-/DYF155S2+/TatT haplotype. This haplotype appeared to be most frequent in Kyrgyz (78.8%) and Uzbeks (83.3%). The question on the origin and the distribution of Y-chromosome variants in Eurasia are discussed.  相似文献   
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27.
In four isolated populations of parthenogenetic Caucasian rock lizard Lacerta unisexualis, variability of (TCC)n loci was examined using multilocus DNA fingerprinting. Unexpectedly high variability of (TCC)n microsatellites was found in all four populations. The mean similarity index was 0.825, which is higher than similarity estimates obtained for other mini- and microsatellite loci in L. unisexualis and parthenogenetic species L. dahli and L. armeniaca studied earlier. The high variation level of (TCC)n loci was shown to be at least partially associated with the presence of a diverged (TCC)n sequence fraction in the L. unisexualis genome. Mutations at some other genetically unstable (TCC)n loci may cause their structural diversity in populations of L. unisexualis.  相似文献   
28.
The acuity test Landolt C's with a complex contour imitating various kinds of high-pass spatial frequency filtering generated as a printed visual acuity charts with a grey background were studied with regard to recognition thresholds. Comparisons were made for recognition thresholds with different complex contours. When the vanishing optotypes are out of focus, their image on the retina fades rapidly into the grey background, rendering them invisible rather than merely blurred as in the standard chart. The data obtained confirm that the recognition distance depends on physical property of complex contour profile and show the importance of the Landolt C spatial frequency spectrum for recognition of different types of the complex contour.  相似文献   
29.
232Th (7.76 x 10(-7) M) and Cd (0.89 x 10(-8) M) in concentrations which do not exceed officially prescribed standards when entering with water do not increase the frequency of chromosome aberrations in comparison with the control. Such concentrations do not cause toxic effects in plants on the levels of tissues and of the whole organism but they do display their activity on the cell level damaging division spindle. Dependence "cadmium concentration-effect" is not linear for any type of cytogenetical damages. At the concentration of cadmium 0.89 x 10(-7) M its influence on formation of division spindle is weakened and the frequency of chromosome aberrations is reducing in comparison with the control and with the effects induced at lower concentrations of cadmium in solution (0.89 x 10(-8) M). Cadmium in high concentration (5.34 x 10(-5) M) causes significant toxic and mutagenic effects.  相似文献   
30.
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