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排序方式: 共有390条查询结果,搜索用时 15 毫秒
151.
Sergiy Tyukhtenko Lalit Deshmukh David R. Janero 《Biochemical and biophysical research communications》2009,390(3):441-446
We report the NMR solution structure of a synthetic 40-mer (T377-E416) that encompasses human cannabinoid receptor-1 (hCB1) transmembrane helix 7 (TMH7) and helix 8 (H8) [hCB1(TMH7/H8)] in 30% trifluoroethanol/H2O. Structural features include, from the peptide’s amino terminus, a hydrophobic α-helix (TMH7); a loop-like, 11 residue segment featuring a pronounced Pro-kink within the conserved NPxxY motif; a short amphipathic α-helix (H8) orthogonal to TMH7 with cationic and hydrophobic amino-acid clusters; and an unstructured C-terminal end. The hCB1(TMH7/H8) NMR solution structure suggests multiple electrostatic amino-acid interactions, including an intrahelical H8 salt bridge and a hydrogen-bond network involving the peptide’s loop-like region. Potential cation-π and cation-phenolic OH interactions between Y397 in the TMH7 NPxxY motif and R405 in H8 are identified as candidate structural forces promoting interhelical microdomain formation. This microdomain may function as a flexible molecular hinge during ligand-induced hCB1 conformer transitions. 相似文献
152.
The objective of this study was to evaluate the effects of a novel oxygen-coordinated niacin-bound chromium(III) complex (NBC) on the reproductive systems of male and female rats, the postnatal maturation and reproductive capacity of their offspring, and possible cumulative effects through multiple generations. Sprague-Dawley rats were maintained on feed containing NBC at dose levels of 0, 4, 15, or 60 ppm for 10 weeks prior to mating, during mating, and, for females through gestation and lactation, across two generations. For the parents (F0 and F1) and the offspring (F1 and F2a), reproductive parameters such as fertility and mating, gestation, parturition, litters, lactation, sexual maturity and development of offspring were assessed. Results from the current study indicated that dietary exposure of NBC to parental male and female rats of both (F0 and F1) the generations during the premating and mating periods, for both sexes, and during gestation and lactation in case of female rats, did not cause any significant incidence of mortality or abnormal clinical signs. Compared to respective controls, NBC exposure did not affect reproductive performance as evaluated by sexual maturity, fertility and mating, gestation, parturition, litter properties, lactation and development of the offspring. Based on the findings of this study, the parental as well as the offspring no-observed-adverse-effect level for NBC was determined to be greater than 60 ppm in diet or equivalent to 7.80 and 8.31 mg/kg body weight/day in male and female rats, respectively. 相似文献
153.
Karen E. Chambers Ryan McDaniell Jeremy D. Raincrow Maya Deshmukh Peter F. Stadler 《Theorie in den Biowissenschaften》2009,128(2):109-120
Large-scale—even genome-wide—duplications have repeatedly been invoked as an explanation for major radiations. Teleosts, the
most species-rich vertebrate clade, underwent a “fish-specific genome duplication” (FSGD) that is shared by most ray-finned
fish lineages. We investigate here the Hox complement of the goldeye (Hiodon alosoides), a representative of Osteoglossomorpha, the most basal teleostean clade. An extensive PCR survey reveals that goldeye has
at least eight Hox clusters, indicating a duplicated genome compared to basal actinopterygians. The possession of duplicated Hox clusters is uncoupled to species richness. The Hox system of the goldeye is substantially different from that of other teleost lineages, having retained several duplicates
of Hox genes for which crown teleosts have lost at least one copy. A detailed analysis of the PCR fragments as well as full length
sequences of two HoxA13 paralogs, and HoxA10 and HoxC4 genes places the duplication event close in time to the divergence of Osteoglossomorpha and crown teleosts. The data are
consistent with—but do not conclusively prove—that Osteoglossomorpha shares the FSGD.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Chi-hua ChiuEmail: |
154.
Harvinder Singh Rupesh K. Deshmukh Abhinay Singh Ashok K. Singh Kishor Gaikwad Tilak R. Sharma Trilochan Mohapatra Nagendra K. Singh 《Molecular breeding : new strategies in plant improvement》2010,25(2):359-364
Simple sequence repeats (SSR) are the DNA markers of choice for genetic analysis in rice (Oryza sativa L.) due to their abundance, high polymorphism and simple assays using agarose gel electrophoresis. In an attempt to find
most variable SSR loci for the agarose gel system, the relationship between SSR length and level of polymorphism was evaluated
in a set of eight diverse rice genotypes using 201 random SSR loci of different repeat motifs and lengths, representing both
genic and intergenic sequences from the 12 rice chromosomes. There was a positive correlation between SSR length and average
number of alleles per locus but linearity of this relationship was limited to the SSR length range of 10–70 bp. The highest
level of polymorphism was in the SSR length range of 51–70 bp, beyond which there was stabilization and then decline of polymorphism
in SSRs longer than 70 bp. Proportion of polymorphic loci in the different SSR length groups also followed similar pattern
with even sharper decline of polymorphism in the highest size range. Here we describe a genome wide set of 436 validated highly
variable SSR (HvSSR) markers with repeat lengths of 51–70 bp for their consistent amplification and high polymorphism. In
the parental lines of three different mapping populations, the HvSSR loci showed more than twice the level of polymorphism
than random SSR markers with average repeat length of 34 bp, and therefore are suitable for QTL mapping and fingerprinting
studies in rice employing agarose gels. 相似文献
155.
156.
Deepika Dayal Mathur Sachin Deshmukh Himani Kaushik Lalit C. Garg 《Applied microbiology and biotechnology》2010,88(4):877-884
Clostridium perfringens types B and D are responsible for enterotoxaemia, one of the major causes of cattle mortality and is therefore of great economic
concern. The epsilon toxin produced by the organism is the major antigenic determinant and has been directly implicated for
the disease causation. In the present paper, we evaluated the biological activity of the recombinant epsilon toxin (rEtx)
produced as soluble protein in Escherichia coli. The rEtx was purified to near homogeneity by a one-step anion-exchange chromatography. The immunological identity of purified
rEtx was confirmed by Western blotting using a monoclonal antibody against the native toxin. The rEtx formed heptamer in the
Madin–Darby canine kidney (MDCK) cells and synaptosomal membrane of mouse brain and was cytotoxic to the MDCK cells with a
CT50 of 30 ng/ml. The rEtx was highly stable and its thermostability profile related well with its biological activity. The rEtx
was purified in large amounts and exhibited all the properties of native toxin and therefore can be used for the development
of vaccine against the pathogen. 相似文献
157.
158.
159.
Taneli Tirkkonen Jaakko Pakarinen Elina Rintala Terhi Ali-Vehmas Harri Marttila Olli AT Peltoniemi Johanna M?kinen 《Acta veterinaria Scandinavica》2010,52(1):21
Background
Animal mycobacterioses are regarded as a potential zoonotic risk and cause economical losses world wide. M. avium subsp. hominissuis is a slow-growing subspecies found in mycobacterial infected humans and pigs and therefore rapid and discriminatory typing methods are needed for epidemiological studies. The genetic similarity of M. avium subsp. hominissuis from human and porcine origins using two different typing methods have not been studied earlier. The objective of this study was to compare the IS1245 RFLP pattern and MIRU-VNTR typing to study the genetic relatedness of M. avium strains isolated from slaughter pigs and humans in Finland with regard to public health aspects. 相似文献160.
Anmaar M. Abdul-Nabi Enas R. Yassin Nobish Varghese Hrishikesh Deshmukh Nabeel R. Yaseen 《PloS one》2010,5(8)
Different fusion oncogenes in acute myeloid leukemia (AML) have distinct clinical and laboratory features suggesting different modes of malignant transformation. Here we compare the in vitro effects of representatives of 4 major groups of AML fusion oncogenes on primary human CD34+ cells. As expected from their clinical similarities, MLL-AF9 and NUP98-HOXA9 had very similar effects in vitro. They both caused erythroid hyperplasia and a clear block in erythroid and myeloid maturation. On the other hand, AML1-ETO and PML-RARA had only modest effects on myeloid and erythroid differentiation. All oncogenes except PML-RARA caused a dramatic increase in long-term proliferation and self-renewal. Gene expression profiling revealed two distinct temporal patterns of gene deregulation. Gene deregulation by MLL-AF9 and NUP98-HOXA9 peaked 3 days after transduction. In contrast, the vast majority of gene deregulation by AML1-ETO and PML-RARA occurred within 6 hours, followed by a dramatic drop in the numbers of deregulated genes. Interestingly, the p53 inhibitor MDM2 was upregulated by AML1-ETO at 6 hours. Nutlin-3, an inhibitor of the interaction between MDM2 and p53, specifically inhibited the proliferation and self-renewal of primary human CD34+ cells transduced with AML1-ETO, suggesting that MDM2 upregulation plays a role in cell transformation by AML1-ETO. These data show that differences among AML fusion oncogenes can be recapitulated in vitro using primary human CD34+ cells and that early gene expression profiling in these cells can reveal potential drug targets in AML. 相似文献