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991.
Functional near-infrared spectroscopy (fNIRS) is recently utilized as a new approach to assess resting-state functional connectivity (RSFC) in the human brain. For any new technique or new methodology, it is necessary to be able to replicate similar experiments using different instruments in order to establish its liability and reproducibility. We apply two different diffuse optical tomographic (DOT) systems (i.e., DYNOT and CW5), with various probe arrangements to evaluate RSFC in the sensorimotor cortex by utilizing a previously published experimental protocol and seed-based correlation analysis. Our results exhibit similar spatial patterns and strengths in RSFC between the bilateral motor cortexes. The consistent observations are obtained from both DYNOT and CW5 systems, and are also in good agreement with the previous fNIRS study. Overall, we demonstrate that the fNIRS-based RSFC is reproducible by various DOT imaging systems among different research groups, enhancing the confidence of neuroscience researchers and clinicians to utilize fNIRS for future applications.  相似文献   
992.
Centrosome defects can result in aneuploidy and genomic instability, and have important implications for breast cancer development. The Aurora-A and BRCA1 proteins interact and both are strongly involved in centrosome regulation. Genetic variants in these two genes may have an effect on breast cancer development. Here, we report a comprehensive single nucleotide polymorphism (SNP) and haplotype-tagging association study on these two genes in 1334 breast cancer cases and 1568 unaffected controls among the Chinese Han population. Apart from a missense SNP, rs2273535 (Phe31Ile), and a probable risk SNP, rs2064863, six htSNPs were analysed in three high-LD blocks of AURKA spanning from 10 kb upstream to 2 kb downstream of AURKA. For BRCA1, six htSNPs were analysed in a large high-LD region covering 98 kb (10 kb was extended to each end of BRCA1). The results showed that four SNPs in AURKA (data in recessive model, rs2273535: OR = 2.19, 95% CI = 1.03-4.66, p = 0.0422; rs2298016: OR = 0.38, 95% CI = 0.18-0.82, p = 0.0141; rs6024836: OR = 1.54, 95% CI = 1.18-2.00, p = 0.0014; rs10485805: OR = 0.68, 95% CI = 0.47-0.98, p = 0.0380) and one SNP in BRCA1 (rs3737559, dominant model OR = 1.35, 95% CI = 1.11-1.64, p = 0.0030) were associated with breast cancer susceptibility. After correction for multiple comparisons (FDR = 0.05), only rs6024836 and rs3737559 remained significant. Two haplotypes (CC of block 2, OR = 20.74, 95% CI = 4.35-98.88, p = 0.0001; GG of block 3, OR = 1.32, 95% CI = 1.12-1.56, p = 0.0010) and one diplotype (AG-GG of block 3, OR = 1.63, 95% CI = 1.18-2.26, p = 0.0031) within AURKA showed strong associations with breast cancer risk. One haplotype of BRCA1 (CTGTTG, OR = 1.30, 95% CI = 1.06-1.59, p = 0.0118) was also associated with breast cancer risk. However, women harbouring both at-risk genotypes of Aurora-A and BRCA1 were at a slightly increased risk compared with those harbouring either at-risk variant alone. Common genetic variants in the AURKA and BRCA1 genes may contribute to breast cancer development.  相似文献   
993.
Hu Q  Hu Z  Li J  Tian B  Xu H  Li J 《Journal of basic microbiology》2011,51(5):467-472
The increasing trend of carbapenem‐resistance (CR) and multi‐drug resistance (MDR) in A. baumannii worldwide has limited the therapeutic effectiveness of antibiotic therapy. The study was conducted to determine the prevalence of carbapenemases and integrons among the isolates of imipenem‐resistant A. baumannii (IRAB). A total of 71 non‐repetitive imipenem‐ resistant A. baumannii isolates were collected and tested for susceptibility to 17 antimicrobials. The modified Hodge test and EDTA‐disc synergy test were performed for the screening of carbapenemases and metallo‐β ‐lactamases (MBLs) production, respectively. Isolates were then subjected to multiplex‐PCR targeting genes encoding for OXA‐type carbapenemase, MBLs and integrases. Random amplified polymorphic DNA (RAPD) genotyping was performed to assess genetic relatedness. All isolates exhibited multi‐drug resistant phenotype. Colistin was the most active antimicrobial agent tested. Seventy‐one isolates (100%) demonstrated positive in the modified Hodge test. Thirty‐nine isolates showed positive in the EDTA‐disc synergy test, however, no MBL genes were detected. All strains possessed a blaOXA‐51‐like gene. The co‐exis‐tence of blaOXA‐51‐like/blaOXA‐23‐like/intI1, blaOXA‐51‐like/blaOXA‐23‐like, blaOXA‐51‐like/blaOXA‐24‐like was detected in 91.6% (n = 65), 5.6% (n = 4), 2.8% (n = 2), respectively. Analysis of the genetic con‐text of blaOXA‐23 showed the presence of ISAba1 upstream of blaOXA‐23. No ISAba1 was detected upstream of blaOXA‐51. Two different gene cassettes were found in these strains, and a high prevalence of aacA4, aadA1 and catB8 genes was observed. RAPD of 71 isolates showed 7 genotypes. The strains were mainly recovered from patients in intensive care unit, neurosurgery and department of respiratory disease. These ?ndings show that multi‐drug resistance in A. baumannii is a common problem. This study also shows a high distribution of blaOXA‐23‐like and intI1 genes in imipenem‐resistant A. baumannii isolates. The clonal spread played an important role in the increase of OXA‐23 producing IRABs in the hospital environment. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
994.
Fu B  Wang F  Sun R  Ling B  Tian Z  Wei H 《Immunology》2011,133(3):350-359
The identification of developmental stages in natural killer (NK) cells, especially in human NK cells, has lagged for decades. We characterize four novel populations defined by CD11b and CD27, which can represent the distinct stages of human NK cells from different tissues. Nearly all NK cells from peripheral blood are CD11b(+) CD27(-) populations whereas NK cells from cord blood have CD11b(+) CD27(-) and CD11b(+) CD27(+) populations. Interestingly, we have found large CD11b(-) CD27(-) populations of NK cells from deciduas. We also demonstrate that each population could be characterized by unique functional and phenotypic attributes. CD11b(-) CD27(-) NK cells display an immature phenotype and potential for differentiation. CD11b(-) CD27(+) and CD11b(+) CD27(+) NK cells show the best ability to secrete cytokines. CD11b(+) CD27(-) NK cells exhibit high cytolytic function. We demonstrate that human NK cells at different developmental stages have special functions and describe a new model of human NK cell differentiation.  相似文献   
995.
Yang Y  Xia T  Zhi W  Wei L  Weng J  Zhang C  Li X 《Biomaterials》2011,32(18):4243-4254
Diabetic skin ulcer is difficult to heal due to the lack of cellular and molecular signals required for normal wound repair. Emulsion electrospinning was adopted to imbed basic fibroblast growth factor (bFGF) into ultrafine fibers with a core-sheath structure to promote the wound healing process. An initially burst release as low as 14.0 ± 2.2% was achieved, followed by gradual release for around 4 wk. In vitro investigations on mouse embryo fibroblasts indicated that bFGF-loaded fibrous mats enhanced cell adhesion, proliferation, and secretion of extracellular matrix (ECM). Skin wounds were created in the dorsal area of diabetic rats for in vivo evaluation of skin regeneration after covered with bFGF-loaded fibrous mats. Compared with fibrous mats infiltrated with free bFGF, bFGF-loaded scaffolds revealed significantly higher wound recovery rate with complete re-epithelialization and regeneration of skin appendages. Higher density and mature capillary vessels were generated during 2 wk after treatment with bFGF-loaded fibers, and there was no fiber fragment observed in the histological sections at week 4 after operation. The gradual release of bFGF from fibrous mats enhanced collagen deposition and ECM remodeling, and the arrangement and component of collagen fibers were similar to normal tissues. The above results demonstrate the potential use of bFGF-loaded electrospun fibrous mats to rapidly restore the structural and functional properties of wounded skin for patients with diabetic mellitus.  相似文献   
996.
Parkinson's disease is a degenerative central nervous system disorder that often impairs motor skills, speech and other functions. We discovered a large Chinese family showing primarily parkinsonism symptoms with autosomal dominant inheritance. Six affected individuals in the family showed typical parkinsonism symptoms, including pill-rolling tremor. Two other affected individuals showed cerebellar ataxia symptoms. A whole-genome scan using the 50K single nucleotide polymorphism array with three different linkage methods detected two positive regions on chromosome 12q24.1 and 5q13.3. The ATXN2 gene, responsible for spinocerebellar ataxia type 2 (SCA2) was located precisely in the center of the positive region on chromosome 12. Further analysis of SCA2 revealed heterozygous pathological CAG expansions in the family. The affected individuals' symptoms were typical of parkinsonism, but complex. Inverse correlation between CAG repeat size and age of onset is not obvious in this pedigree. This parkinsonism-predominant SCA2 family shared the same disease gene locus with other 'standard' SCA2 families, but it is possible that variations in one or more modifier genes might account for the parkinsonism-predominant SCA2 predisposition observed in this pedigree.  相似文献   
997.
Monoclonal antibodies (MAbs) against Haemophilus parasuis were generated by fusing spleen cells from BALB/c mice immunized with whole bacterial cells with SP2/0 murine myeloma cells. Desirable hybridomas were screened by enzyme-linked immunosorbent assay (ELISA). Neutralizing MAb 1D8 was selected in protection assays. ELISA results demonstrated that 1D8 can react with all 15 serotypes of H. parasuis and field isolate H. parasuis HLJ-018. Passive immunization studies showed that mice inoculated intraperitoneally with 1D8 had significantly reduced prevalence of H. parasuis colonization in the blood, lung, spleen, and liver and had prolonged survival time compared to that of the control group. Furthermore, the passive transfer experiment indicated that MAb 1D8 can protect mice from both homologous and heterologous challenges with H. parasuis. Using two-dimensional gel electrophoresis (2-DE), the immunoreactive protein target for MAb 1D8 was identified. The data presented confirm the protective role of MAb 1D8 and identify OmpA as the target of the protective monoclonal antibody. The data suggest that OmpA is a promising candidate for a subunit vaccine against H. parasuis.  相似文献   
998.
Li  Yuying  Huang  Haixin  Lan  Tian  Wang  Wei  Zhang  Jie  Zheng  Min  Cao  Liang  Sun  Wenchao  Lu  Huijun 《Virus genes》2021,57(3):284-288

Lyon IARC polyomavirus (LIPyV), a newly discovered polyomavirus (PyV), was first identified in 2017 in human skin samples in the USA. Later, it was detected in several other countries in samples of human and feline origin. Our aim was to find out if the virus occurs in China. To this end, 100 fecal samples were collected from cats with diarrhea in Guangxi Province during 2016 and 2018 and tested with polymerase chain reaction (PCR). Only 2 samples that originated from two related individuals were found to be positive. Based on the sequence identity of the 240-bp PCR products, the two positive samples supposedly contained identical viruses. Therefore, only one of them, which was designated as LIPyV-GXNN01, was selected for full genome amplification, cloning, sequencing and analysis. LIPyV-GXNN01, which comprises 5,263 nucleotides, has an early region that consists of small T antigen (ST-Ag) and large T antigen (LT-Ag) and a late region coding for the VP1, VP2, and VP3 structural proteins. Moreover, the LIPyV-GXNN01 strain structural proteins share 95.9–99.4%, 97.6–99.2%, and 97.1–99.2% nucleic acid identity with the VP1, VP2, and VP3of other LIPyV reference strains, respectively. A phylogenetic analysis revealed that GXNN01 clustered together with previously reported LIPyV strain. This present study is the first report of LIPyV in China.

  相似文献   
999.
目的 探讨miR-145-5p对甲状腺癌细胞侵袭和转移的影响.方法 将miR-145-5p mimic质粒、mimic-NC质粒、TPM3质粒分别或联合转入甲状腺癌细胞,RT-qPCR检测miR-145-5p与TPM3 mRNA的表达,双荧光素酶报告检测靶向关系,Transwell法检测细胞侵袭能力,划痕实验检测细胞迁...  相似文献   
1000.
Clinical and Experimental Medicine - Breast cancer is the most common cancer among women, with metastasis as the principal cause of mortality. MiR-1225 has been reported to play roles in the...  相似文献   
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