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1.
O. B. Kazakova E. F. Khusnutdinova G. A. Tolstikov K. Yu. Suponitsky 《Russian Journal of Bioorganic Chemistry》2010,36(4):512-515
New olean-18(19)-ene triterpenoids were effectively synthesized by the interaction of allobetulin or its acetate with phosphorous
oxychloride in refluxing pyridine. The structures of the synthesized 17-chloromethyloleane-18(19)-enes were confirmed by NMR
spectroscopy and X-ray analysis. 相似文献
2.
3.
Excess amino acid polymorphism in mitochondrial DNA: contrasts among genes from Drosophila, mice, and humans 总被引:13,自引:3,他引:10
Recent studies of mitochondrial DNA (mtDNA) variation in mammals and
Drosophila have shown an excess of amino acid variation within species
(replacement polymorphism) relative to the number of silent and replacement
differences fixed between species. To examine further this pattern of
nonneutral mtDNA evolution, we present sequence data for the ND3 and ND5
genes from 59 lines of Drosophila melanogaster and 29 lines of D. simulans.
Of interest are the frequency spectra of silent and replacement
polymorphisms, and potential variation among genes and taxa in the
departures from neutral expectations. The Drosophila ND3 and ND5 data show
no significant excess of replacement polymorphism using the
McDonald-Kreitman test. These data are in contrast to significant
departures from neutrality for the ND3 gene in mammals and other genes in
Drosophila mtDNA (cytochrome b and ATPase 6). Pooled across genes, however,
both Drosophila and human mtDNA show very significant excesses of amino
acid polymorphism. Silent polymorphisms at ND5 show a significantly higher
variance in frequency than replacement polymorphisms, and the latter show a
significant skew toward low frequencies (Tajima's D = -1.954). These
patterns are interpreted in light of the nearly neutral theory where mildly
deleterious amino acid haplotypes are observed as ephemeral variants within
species but do not contribute to divergence. The patterns of polymorphism
and divergence at charge-altering amino acid sites are presented for the
Drosophila ND5 gene to examine the evolution of functionally distinct
mutations. Excess charge-altering polymorphism is observed at the carboxyl
terminal and excess charge-altering divergence is detected at the amino
terminal. While the mildly deleterious model fits as a net effect in the
evolution of nonrecombining mitochondrial genomes, these data suggest that
opposing evolutionary pressures may act on different regions of
mitochondrial genes and genomes.
相似文献
4.
A. S. Karunas B. B. Yunusbaev Yu. Yu. Fedorova G. F. Gimalova N. N. Ramazanova L. L. Gur’eva L. A. Mukhtarova Sh. Z. Zagidullin E. I. Etkina E. K. Khusnutdinova 《Molecular Biology》2011,45(6):911-920
Bronchial asthma is a chronic inflammatory respiratory disease caused by a complex interaction of environmental influences
and genetic susceptibility. The first genome-wide association study of bronchial asthma discovered a significant association
between single nucleotide polymorphisms (SNPs) located within the genomic region 17q12-q21 and childhood bronchial asthma
in individuals of European descent. This result was later replicated in a number of independent population samples of European
and Asian origin. Here we report the results of the first genome-wide association study of bronchial asthma in the Volga-Urals
region of Russia. The study involved 358 unrelated patients with physician-diagnosed bronchial asthma and 369 disease-free
control subjects of different ethnicity (Russians, Tatars, and Bashkirs). DNA specimens were genotyped using an Illumina Human610
quad array as a part of the GABRIEL project (EC contract no. LSHB-CT-2006-018996). After QC filtering procedures, a final
set of 550 915 SNPs genotyped in 330 patients and 348 controls was tested for association with bronchial asthma. Five markers
on chromosome 17q12-21 showed significant association with bronchial asthma (p ≤ 4.79 × 10−7). The rs7216389 SNP located in GSDMB intron 1 showed the strongest evidence for association (p = 1.01 × 10−7). Association with childhood asthma (p = 1.97 × 10−6 for rs7216389) was stronger than with late-onset asthma (p = 1.8 × 10−4 for rs7216389). A replication study of three SNPs located within GSDMB confirmed association only with childhood asthma. In sum, these results suggest that genetic variants of 17q12–q21 play an
important role in susceptibility to bronchial asthma in the Volga-Urals region of Russia. 相似文献
5.
Fedorova Yu. Yu. Karunas A. S. Murzina R. R. Savelieva O. N. Gimalova G. F. Gatiyatullin R. F. Etkina E. I. Khusnutdinova E. K. 《Russian Journal of Genetics》2019,55(12):1520-1527
Russian Journal of Genetics - Bronchial asthma (BA) is a common severe and disabling multifactorial disease. Up to 50–60% of differences in sensitivity to therapy in patients with BA is due... 相似文献
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7.
Sara Santarossa Alexandra R. Sitarik Christine Cole Johnson Jia Li Susan V. Lynch Dennis R. Ownby Alex Ramirez Germaine LM. Yong Andrea E. Cassidy-Bushrow 《Journal of Exercise Nutrition & Biochemistry》2021,25(4):24
[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children.[Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2.[Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R2 = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA.[Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear. 相似文献
8.
Borodina TA Ivanov DV Khusnutdinova EK Spitsyn VA Baranova AV Iankovskiĭ NK 《Genetika》2001,37(1):117-119
DNA samples of unrelated subjects from the Volga-Ural region of Russia were examined to study allele polymorphism of the pentanucleotide repeat (TTGTG)8 localized to an intron of the tumor suppressor gene ING1. STR marker was registered in the EMBL database with the accession number AJ277387. In a sample of 119 individuals, three pentanucleotide alleles consisting of seven, eight, and nine repeated monomers were revealed. The allele frequencies were 0.24, 0.74, and 0.02, respectively. Heterozygosity was 0.45. On the basis of these data, the repeat can be regarded as a polymorphic STR marker for the ING1 gene and used in population and clinical studies. 相似文献
9.
The frequency of the GSTM1 gene deletion homozygotes in eight populations of the Volga-Ural region belonging according to linguistic classification to Turkic (Bashkirs, Tatars, and Chuvashs), Finno-Ugric (Maris, Komis, Mordovians, and Udmurts), and Eastern-Slavic (Russians) ethnic groups, was examined by means of PCR technique. The frequency of the deletion homozygotes varied from 41.4% in Bashkirs to 61.3% in Mordovians. The mean deletion frequency comprised 50.1%, which was consistent with the data for European populations (chi 2 = 0.009). 相似文献
10.
Polymorphism at the dopamine transporter gene (DAT1) in populations of the Volga-Ural region was examined by means of polymerase chain reaction. Statistically significant differences in the dopamine transporter gene allele and genotype frequency distribution were revealed both between the populations belonging to one ethnic group and between the populations from different linguistic families. 相似文献