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51.
Bocaviruses are associated with many human infectious diseases, such as respiratory tract infections, gastroenteritis, and hepatitis. Rats are known to be reservoirs of bocaviruses, including rodent bocavirus and rat bocavirus. Recently, ungulate bocaparvovirus 4, a known porcine bocavirus, has also been found in rats. Thus, investigating bocaviruses in rats is important for determining the origin of the viruses and preventing and controlling their transmission. To the best of our knowledge, no study to date has investigated bocaviruses in the livers of rats. In this report, a total of 624 rats were trapped in southern China between 2014 and 2017. Liver and serum samples from rats were tested for the prevalence of bocaviruses using PCR. Sequences related to ungulate bocaparvovirus 4 and rodent bocavirus were detected in both liver and serum samples. Interestingly, the prevalence of ungulate bocaparvovirus 4 (reference strain:KJ622366.1) was higher than that of rodent bocavirus (reference strain:KY927868.1) in both liver (2.24% and 0.64%, respectively) and serum samples (2.19% and 0.44%, respectively). The NS1 regions of ungulate bocaparvovirus 4 and rodent bocavirus related sequences displayed over 84% and 88% identity at the nucleic acid and amino acid levels, respectively. Furthermore, these sequences had similar genomic structure, genomic features, and codon usage bias, and shared a common ancestor. These viruses also displayed greater adaptability to rats than pigs. Our results suggested that ungulate bocaparvovirus 4 and rodent bocavirus may originate from rats and may be different genotypes of the same bocavirus species.  相似文献   
52.

Background

In recent years, the fungal infectious disease zygomycosis has increased in incidence worldwide, especially among the immunodeficient population. Despite the rates of zygomycosis-related death and deformation being very high, the mechanism(s) by which the fungal pathogens cause these severe manifestations remain unknown.

Methods

Using the associated Rhizomucor variabilis species, which can selectively induce cutaneous zygomycosis in otherwise healthy individuals, we investigated the host mechanisms of infection-related responses, including cytokine and chemokine expression as well as contributions of particular T cell subsets. siRNA specifically targeting IL-22,IL-17 and IFN-γ were used to down-regulate expression of those molecules.

Results

In mouse models of infection, IL-22 was implicated in development of Rhizomucor spp.-induced skin lesions. In cultured human peripheral blood monocytes, R. pusilluscan, which is often found in immunodeficient patients, induced the production of IL-22, while R. variabilis did not. Moreover, Rhizomucor spp.-induced secretion of Il-22 from CCR6+CCR4+CCR10+ cells was down-regulated by knockdown of IL-22 related signaling receptors, RORC and ARH.

Conclusion

Our data strongly suggest that avoidance of IL-22 may be one mechanism by which mucor species produce morbidity and mortality in infected individuals.  相似文献   
53.
Vascular malformations (VMs) are common congenital and neonatal dysmorphogenesis. VMs mostly occur sporadically with a few exceptions of inheritability. Tie2/angiopoietins-2 (Ang-2) and VEGF/KDR pathways are known to be involved in normal and pathogenic angiogenesis. Our study was aimed to test the contribution of these pathway gene variants to VMs. A total of 8 variants were found among 103 VM patients and 142 healthy controls. These variants comprised rs638203, rs639225, rs80338908 and rs80338909 in Tie2 gene, rs1870377 and rs2305949 in KDR gene, rs79337921 and rs34590960 in ANTXR1 gene. Our results indicated that rs638203 (p = 0.029) and rs639225 (p = 0.018) in Tie2 gene were associated with VM. A further bioinformatics analysis suggested the rs638203-G and rs639225-G might cause an abnormal splicing of Tie2 gene into to a defective protein. Our results identified two novel Tie2 gene polymorphisms with genetic susceptibility to VMs, although future functional validation of the two polymorphisms is warranted in the future.  相似文献   
54.
55.

Background

Previous association studies examining the relationship between the APOC1 polymorphism and susceptibility to Alzheimer’s disease (AD) have shown conflicting results, and it is not clear if an APOC1 variant acts as a genetic risk factor in AD etiology across multiple populations.

Methods

To confirm the risk association between APOC1 and AD, we designed a case-control study and also performed a meta-analysis of previously published studies.

Results

Seventy-nine patients with AD and one hundred fifty-six unrelated controls were included in case-control study. No association was found between the variation of APOC1 and AD in stage 1 of our study. However, our meta-analysis pooled a total of 2092 AD patients and 2685 controls. The APOC1 rs11568822 polymorphism was associated with increased AD risk in Caucasians, Asians and Caribbean Hispanics, but not in African Americans. APOE ε4 carriers harboring the APOC1 insertion allele, were more prevalent in AD patients than controls (χ2 = 119.46, OR = 2.79, 95% CI = 2.31–3.36, P<0.01).

Conclusions

The APOC1 insertion allele, in combination with APOE ε4, likely serves as a potential risk factor for developing AD.  相似文献   
56.
The allelic distribution of the Y-chromosome specific microsatellite DYS19 in the Han population and in the Daur, Oroqen and Ewenki ethnic groups (Northeast China) was analyzed by PCR and denatured polyacrylamide gel electrophoresis. The allelic distribution in the Han population group is as follows: A = 2.90%, B = 26.09%, C = 26.09%, D = 29.98%, E = 15.94%. This allelic distribution differs statistically significant from that observed in the three other ethnic groups (p < 0.05). Furthermore the polymorphism of the Y-chromosome specific Alu insert sequence DYS287 was tested in these four groups. However, no Alu sequence insert was found.  相似文献   
57.
Mucin-type core 1-derived O-glycans, one of the major types of O-glycans, are highly expressed in mammary gland epithelium. Abnormal O-glycans such as Tn antigen are found in over 90% of breast cancers; however, the in vivo role of these aberrant O-glycans in the etiology of breast cancer is unclear. We generated mice with mammary epithelial specific deletion of core 1-derived O-glycans. By crossing with two spontaneous mouse breast cancer models, we determined that loss of core 1-derived O-glycans delays the onset and progression of breast cancer development. Deficiency of core 1 O-glycosylation impaired the localization of Muc1, a major O-glycoprotein, on the apical surfaces of mammary epithelium. Signaling mediated by Muc1, which is critical for breast cancer development, was also defective in the absence of core 1 O-glycans. This study reveals an unexpected role of core 1-derived O-glycans in breast cancer development in mice.  相似文献   
58.
59.
UDP-glucose pyrophosphorylase (UGPase) is an enzyme involved in the biosynthesis of UDP-D-galactose, a subunit of agar in red seaweeds. The relationship between agar content and expression levels of the UGPase encoding gene (glugp) was studied in thalli under different treatment conditions using a quantitative real-time PCR-based method (qPCR). Moreover, this qPCR method for the measurement of glugp expression was also applied to commercial varieties of Gracilariopsis lemaneiformis, a red macroalga, in order to examine its reliability on material obtained from field cultivation. Both the agar content and glugp gene expression in G. lemaneiformis grown under low salinity (17?‰) conditions for 1 week showed a slight increase in comparison with the control group (33?‰ salinity, natural salinity of seawater), but the difference was not statistically significant (P?>?0.05). However, when the culture time was extended to 2 weeks, the increase in both the agar yield and glugp expression became significant (P?glugp expression (P?>?0.05). Our results suggest that glugp gene expression and agar content are highly positively correlated and that the measurement of glugp expression, using only a small amount of thalli material, may be an efficient approach to evaluate agar content. In addition, both the agar content and glugp expression in cultivars 981, 07-2, and ZC differed significantly from those of MT-18. The findings of this study suggest that UGPase may be involved in agar biosynthesis and indicate that glugp gene expression could be a fairly reliable molecular marker to reflect the agar content of strains during breeding and selection of G. lemaneiformis.  相似文献   
60.
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