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991.
992.
Knowledge of the G6PD genotype and its associated enzyme activity is significant for population genetics, diagnosis of disease, and management of patients. We tested 2,872 unrelated subjects from a Hakka population in China for G6PD activity by the WHO standard method and for genotype by DHPLC and DNA sequencing. Among female heterozygotes, 78.5% had relatively normal enzyme activity. The phenotype frequency of G6PD deficiency is 0.028, and the causal allele frequency is 0.060 in females. The accuracy, sensitivity, and specificity of DHPLC are more than 98% for detecting G6PD-deficient hemizygotes, heterozygotes, and homozygotes. Measuring enzyme activity alone is not sufficient for the diagnosis of heterozygotes. A combination of enzyme activity and DNA analysis should be used.  相似文献   
993.
The B3GNT5 gene is a candidate for the F4ab/ac receptor conferring susceptibility to enterotoxigenic Escherichia coli (ETEC) F4ab/ac in pigs. In this study, we screened mutations in the complete coding region of the porcine B3GNT5 gene and identified four SNPs in the 3' untranslated regions. We genotyped the four SNPs across a large-scale White Duroc × Chinese Erhualian F2 resource population (total F2 = 755) and 292 purebred piglets representing 15 Chinese and Western breeds. We found that the g.1476G→A locus and haplotypes [A;T;G;T] and [A;G;G;T] had significant association with susceptibility to ETEC F4ac in the resource population. None of the B3GNT5 polymorphisms and haplotypes was associated with susceptibility to ETEC F4ab/ac in outbred piglets. This result, together with other reports, supports the conclusion that B3GNT5 is not the responsible gene encoding the ETEC F4ab/ac receptors.  相似文献   
994.
Mycoplasma pneumoniae is an important causative agent of atypical pneumonia. This study was to determine the ability of a DNA expression vector, which encodes the carboxy terminal region of the M. pneumoniae P1 protein (P1C), to induce humoral and cellular immune responses and to protect against M. pneumoniae infection in BALB/c mice. Mice were immunized with pcDNA3.1/P1C by either intramuscular injection (i.m.) or intranasal inoculation (i.n.). Our results showed that p1c DNA immunization generates detectable antibodies specific to M. pneumoniae, and elicits high levels of IgG1, IgG2a, and IgG2b isotypes (P?< 0.01). The levels of IFN-γ and IL-4 in spleen cells of the immunized mice were significantly elevated by immunization via both the i.m. and i.n. methods. Moreover, p1c DNA-immunized mice exhibited detectable protection against M. pneumoniae infection. The lung tissue inflammation was relieved and the histopathologic score (HPS) of pcDNA3.1/P1C-immunized mice was significantly decreased than those in phosphate-buffed saline (PBS) or vaccine-vector-immunized mice (P?< 0.01), whereas there were no significant differences in HPS between i.m. and i.n. vaccination (P?> 0.05). Our results suggest that pcDNA3.1/P1C could be useful for developing a vaccine against M. pneumoniae infection.  相似文献   
995.
996.
JR Wu  R Zeng 《FEBS letters》2012,586(18):2841-2845
Single nucleotide polymorphisms (SNPs) are one type of genomic DNA variations in a population. Correspondingly, single amino-acid polymorphisms (SAPs) derived from non-synonymous SNPs represent protein variations in a population. Recently, using proteomic approaches, SAPs in the plasma proteomes of an Asian population were systematically identified for the first time. That study showed that heterozygous and homozygous proteins with various SAPs have different associations with particular traits in the population. Recent discoveries of widespread differences between RNA and DNA sequences indicate that RNA editing is also a source of SAPs - one that is independent of genomic SNPs. Furthermore, we argue that there are de novo SAPs that are not encoded by either DNA or RNA sequences.  相似文献   
997.
998.
999.
Sequence variability in three mitochondrial DNA (mtDNA) regions, namely cytochrome c oxidase subunit 3 (cox3), NADH dehydrogenase subunits 1 and 4 (nad1 and nad4) in Spirometra erinaceieuropaei spargana from different geographical regions in China was examined. A portion of each of the cox3 (pcox3), nad1 (pnad1) and nad4 genes (pnad4) were amplified separately from individual S. erinaceieuropaei spargana by polymerase chain reaction (PCR). Representative amplicons were subjected to sequencing in order to estimate sequence variability. The sequences of pcox3, pnad1 and pnad4 were 541, 607 and 847?bp in length, respectively. The A+T contents of the sequences were 68.39-68.76% (pcox3), 63.76-64.91% (pnad1) and 67.18-67.77% (pnad4), respectively, while the intra-specific sequence variations within each of the S. erinaceieuropaei spargana were 0-1.5% for pcox3, 0-2.8% for pnad1 and 0-2.7% for pnad4. Phylogenetic analysis using neighbour joining (NJ), maximum likelihood (ML) and maximum parsimony (MP) methods, indicated that all the spargana isolates in Hunan Province represented S. erinaceieuropaei. These findings demonstrated clearly the usefulness of the three mtDNA sequences for population genetics studies of S. erinaceieuropaei spargana of human and animal health significance.  相似文献   
1000.
Li ZY  Sun R  Li J  Song YX  Lin YC  Zeng X  He HJ  Wei J  Yang F  Zheng HQ  Lv ZY  Wu ZD 《Journal of helminthology》2012,86(4):410-417
The pathogenesis of angiostrongyliasis, resulting from Angiostrongylus cantonensis invasion of the human central nervous system, remains elusive. Anthelmintics are usually used to kill worms, although dead worms in the brain may cause severe inflammation which will lead to central nervous system damage. Therefore, combination therapy with anthelmintics and anti-inflammatory drugs in the treatment of human angiostrongyliasis needs further study. To evaluate the efficacy of albendazole combined with a marine fungal extract (m2-9) in A. cantonensis infection, BALB/c mice infected by the third-stage larvae of A. cantonensis were divided into three groups: mice treated with albendazole or m2-9 alone or in combination from day 5 post-inoculation (PI). Several efficacy parameters were recorded, including weight change, worm recovery, neurological function, behavioural analysis, eosinophil and leucocyte counts. The results showed that combination therapy increased body weight, reduced worm burden, improved learning ability, memory and action, decreased neurological dysfunction and leucocyte response in these mice. The combination of albendazole and m2-9 treatment significantly decreased leucocyte response and increased the frequency of rearing, compared to infected mice treated with either drug alone. Therefore, m2-9 is a natural product with potentially significant therapeutic value for angiostrongyliasis and is worthy of further study.  相似文献   
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