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971.
972.
The destruction of calcium homeostasis is an important factor leading to neurological diseases. Store-operated Ca2+ (SOC) channels are essential for Ca2+ homeostasis in many cell types. However, whether SOC channels are involved in astrocyte activation induced by lipopolysaccharide (LPS) still remains unknown. In this study, we used LPS as an exogenous stimulation to investigate the role of SOC channels in astrocyte activation. Using calcium imaging technology, we first found that SOC channels blockers, 1-[h-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1H-imidazole (SKF-96365) and 2-aminoethyldiphenyl borate (2-APB), inhibited LPS induced [Ca2+]i increase, which prompted us to speculate that SOC channels may be involved in LPS induced astrocyte activation. Further experiments confirmed our speculation shown as SOC channels blockers inhibited LPS induced astrocyte activation characterized as cell proliferation by MTS and BrdU assay, raise in glial fibrillary acidic protein expression by immunofluorescence and Western Blot and secretion of interleukin 6 (IL-6) and interleukin 1β (IL-1β) by ELISA. So, our studies showed that SOC channels are involved in LPS-induced astrocyte activation.  相似文献   
973.
974.
975.

Background

Emerging evidence showed that the most common functional polymorphism (-251A>T, rs4073) in the promoter region of the interleukin-8 (IL-8) gene is involved in the regulation of the activities of interleukin-8, thus increasing an individual's susceptibility to oral cancer; but individually published results are inconclusive. The aim of this meta-analysis was to investigate the associations between IL-8 -251A>T polymorphism and oral cancer risk.

Methods

The PubMed, Embase, Web of Science and CBM databases were searched for all articles published up to October 1st, 2012 that addressed IL-8 -251A>T polymorphism and oral cancer risk. Statistical analyses were performed using STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

Six case–control studies were included with a total of 1324 oral cancer cases and 1879 healthy controls. When all available studies were pooled into the meta-analysis, the results showed that the AA and AT genotypes of IL-8 -251A>T polymorphism were associated with increased risk of oral cancer (OR = 1.23, 95% CI: 1.03–1.46, P = 0.025; OR = 1.25, 95% CI: 1.07–1.47, P = 0.006; respectively). In the subgroup analysis by ethnicity, significant associations were observed between the AA and AT genotypes of IL-8 -251A>T polymorphism and increased risk of oral cancer among Caucasian populations (OR = 1.40, 95% CI: 1.14–1.72, P = 0.001; OR = 1.29, 95% CI: 1.06–1.57, P = 0.011; respectively). However, no statistically significant associations were found between IL-8 -251A>T polymorphism and oral cancer risk among Asian populations.

Conclusions

Results from the current meta-analysis indicate that the AA and AT genotypes of IL-8 -251A>T polymorphism might increase the risk of oral cancer, especially among Caucasian populations.  相似文献   
976.
Idiopathic basal ganglia calcification (IBGC) is a rare neuropsychiatric disorder characterized by bilateral and symmetric cerebral calcifications. Recently, SLC20A2 was identified as a causative gene for familial IBGC, and three mutations were reported in a northern Chinese population. Here, we aimed to explore the mutation spectrum of SLC20A2 in a southern Chinese population. Sanger sequencing was employed to screen mutations within SLC20A2 in two IBGC families and 14 sporadic IBGC cases from a southern Han Chinese population. Four novel mutations (c.82G > A p.D28N, c.185T > C p.L62P, c.1470_1478delGCAGGTCCT p.Q491_L493del and c.935-1G > A) were identified in two families and two sporadic cases, respectively; none were detected in 200 unrelated controls. No mutation was found in the remaining 12 patients. Different mutations may result in varied phenotypes, including brain calcification and clinical manifestations. Our study supports the hypothesis that SLC20A2 is a causative gene of IBGC and expands the mutation spectrum of SLC20A2, which facilitates the understanding of the genotype–phenotype correlation of IBGC.  相似文献   
977.
In Parkinson’s disease, dopaminergic neuron damage/death causes the release of soluble substances that are selectively toxic to neighboring/additional dopaminergic neurons through the activation of microglia. Hsp60 can be released from injured cells of central nervous system to activate microglia. However, its expression and role in Parkinson’s disease has not been well understood. Here, we performed a 6-OHDA treated Parkinson’s disease model in adult rats. Western blot analysis showed a time-course expression of Hsp60, which decreased gradually and then rose back. Immunofluorescence staining showed that Hsp60 was decreased in dopaminergic neuron, and most Hsp60 located on the surface of activated microglia. Furthermore, in cellular Parkinson’s disease model, Hsp60 was obviously detected in the culture supernatants after 6-OHDA treatment, and a concomitant decrease in cell extracts. Taken together, our results suggested that Hsp60 could be released extracellularly to activate microglia in Parkinson’s disease model.  相似文献   
978.
Tricho–rhino–phalangeal syndrome (TRPS) is a rare autosomal dominant disorder. Deletion or mutation of the TRPS1 gene leads to the tricho–rhino–phalangeal syndromes type I or type III. In this article, we describe a Chinese patient affected with type I TRPS and showing prominent pilar, rhinal and phalangeal abnormalities. Mutational screening and sequence analysis of TRPS1 gene revealed a previously unidentified four-base-pair deletion of nucleotides 1783–1786 (c.1783_1786delACTT). The mutation causes a frame shift after codon 593, introducing a premature stop codon after 637 residues in the gene sequence. This deletion is an unquestionable loss-of-function mutation, deleting all the functionally important parts of the protein. Our novel discovery indicates that sparse hair and metacarpal defects of tricho–rhino–phalangeal syndromes in this patient are due to this TRPS1 mutation. And this data further supports the critical role of TRPS1 gene in hair and partial skeleton morphogenesis.  相似文献   
979.
ERCC4 plays an essential role in the nucleotide excision repair (NER) pathway, which is involved in the removal of a wide variety of DNA lesions. To determine whether the ERCC4 tagging SNPs (tSNPs) are associated with risk of gastric cancer, we conducted a hospital-based case-control study of 350 cases and 468 cancer-free controls. In the logistic regression (LR) analysis, we found a significantly decreased risk of gastric cancer associated with the rs744154 GC/CC genotypes [adjusted odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.42–0.75, false discovery rate (FDR) P = 0.003] compared with the wild-type GG genotype. Haplotype-based association study revealed that the CGC haplotype that containing the rs744154 C allele can decrease the risk of gastric cancer compared with the most common haplotype GGT (adjusted OR = 0.61, 95% CI = 0.46–0.81). Using the multifactor dimensionality reduction (MDR) analysis, we identified that the SNP rs744154 and smoking status were the best two predictive factors for gastric cancer with a testing accuracy of 55.76% and a perfect cross-validation consistency (CVC) of 10 (P = 0.001). Furthermore, the smokers with the rs744154 GC/CC genotypes showed a decreased risk of gastric cancer (adjusted OR = 0.55, 95% CI = 0.35–0.85) compared with the smokers with the GG genotype using multivariate LR analysis. The above findings consistently suggested that genetic variants in the ERCC4 gene may play a protective role in the etiology of gastric cancer, even in the smokers.  相似文献   
980.
Alopecia areata (AA) is an inflammatory hair loss disorder with a major genetic component, which may cause great psychosocial distress for those affected. Studies have shown that interleukin-1 (IL-1) is a very potent inducer of hair loss and a significant human hair growth inhibitor. The 4-bp insertion/deletion (Indel) polymorphism (rs3783553) within the 3′ untranslated regions of IL1A gene has been suggested to be associated with risk of various types of cancers, possibly through regulating expression of IL-1α levels. In the current study, we estimated the susceptibility to AA associated with rs3783553 in two independent case–control panels of Eastern and Southern Chinese populations, totally containing 313 AA cases and 626 healthy controls. Logistic regression analysis showed that the heterozygote and the homozygote 4-bp ins/ins confer a significantly lower risk of AA in both panels and total subjects [odds ratio (OR) = 0.55, 95% confidence interval (C.I.) = 0.41–0.75, P = 6.24 × 10− 5; OR = 0.47, 95% C.I. = 0.28–0.76, P = 0.001, respectively]. Stratification analysis based on age onset showed that the protective roles of ins/del and ins/ins genotype against developing AA was more obvious in AA patients with early age onset (< 30 years) under dominant model (OR = 0.48, 95% C.I. = 0.29–0.77, P = 0.001). The results of luciferase assay showed that rs3783553 could influence expression of IL-1α in a miR-122 dependant manner. Taken together, our results suggested that the IL1A 4-bp indel polymorphism may be a marker for genetic susceptibility to patchy (mild) AA in Chinese populations, likely through miR-122 mediated regulation.  相似文献   
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