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991.
In this study, four strains of Japanese Encephalitis Virus (JEV) were isolated from the cerebrospinal fluid of aborted fetuses or stillborn piglets collected randomly from a number of piggeries in central China. The E genes were cloned by RT–PCR and sequenced. Phylogenetic analysis was performed with 48 JEV isolates previously reported in China and other countries, and showed that all four isolates can be classified into the subcluster of genotype III. The results strongly suggest that the genotype III of JEV is the major variant currently circulating in the swinery of central China.  相似文献   
992.
Alcohol hepatic toxicity in heavy drinkers is associated with high endotoxin blood levels and increased intestinal permeability. Because endotoxins can cross damaged mucosa, we investigated the mechanisms through which ethanol impairs the colonic epithelium of rats submitted to acute alcohol intake. Colonic permeability to (51)Cr-ethylenediamintetraacetic acid was increased 24 hours after 3.0 g/kg ethanol intake (3.2 +/- 0.2% versus 2.2 +/- 0.2%) and was associated with significant endotoxemia. Antibiotics and doxantrazole (a mast cell membrane stabilizer) significantly inhibited the effect of ethanol. Two hours after intake, plasma concentrations of ethanol were twofold higher in antibiotic-treated rats than in controls (155.8 +/- 9.3 mg/dl versus 75.7 +/- 7.6 mg/dl, P < 0.001). Lumenal concentrations of acetaldehyde were markedly increased after ethanol intake (132.6 +/- 31.6 micromol/L versus 20.8 +/- 1.4 micromol/L, P < 0.05) and antibiotics diminished this increase (86.2 +/- 10.9 micromol/L). In colonic samples mounted in Ussing chambers, acetaldehyde but not ethanol increased dextran flux across the mucosa by 54%. Doxantrazole inhibited the effect of acetaldehyde. This study demonstrates that an acute and moderate ethanol intake alters the epithelial barrier through ethanol oxidation into acetaldehyde by the colonic microflora and downstream mast cell activation. Such alterations that remain for longer periods could result in excessive endotoxin passage, which could explain the subsequent endotoxemia frequently observed in patients with alcoholic liver disease.  相似文献   
993.
Ye L  Lin J  Sun Y  Bennouna S  Lo M  Wu Q  Bu Z  Pulendran B  Compans RW  Yang C 《Virology》2006,351(2):260-270
Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection.  相似文献   
994.

Background

The aim of the study was to determine whether the innovative non-contact optical low-coherence reflectometry method utilized by the Lenstar LS 900® agrees sufficiently with applanation ultrasound A-scan technique in routine biometric measurement and intraocular lens power calculation to replace it.

Methods

Twenty-two patients hospitalized at our eye clinic undergoing cataract surgery were assigned to have five consecutive measurements of axial length by two examiners in a single session using applanation ultrasound and the Lenstar. The applanation ultrasound intraocular lens power calculation was based on automated keratometry and applanation ultrasound axial length measurements. The Lenstar intraocular lens power calculation was based on its measurement of keratometry and axial length. Bland–Altman analysis was used to assess interobserver repeatability of applanation ultrasound and the Lenstar as well as agreement between the Lenstar and applanation ultrasound for axial length measurement and intraocular lens power calculation.

Results

Thirty-two eyes of 22 patients were analyzed. In 95% of the observations, predicted refractive error corresponded to –0.26?±?0.62 D and 0.01?±?0.20 D obtained with applanation ultrasound and the Lenstar, respectively.

Conclusions

Based on excellent repeatability of the Lenstar and acceptable repeatability of applanation ultrasound, two techniques may be used interchangeably. The predicted refractive error of ±0.20 D in 95% of the observations has never been achieved. Optical low-coherence reflectometry might become a new standard method for biometric measurement needed for intraocular lens-power calculation in patients with cataract.
  相似文献   
995.
本文用放射自显影观察了自羊提取的抗人胃腺癌免疫核糖核酸对人胃腺癌细胞株(7901)的作用,结果表明,抗胃腺癌免疫核糖核酸能通过致敏淋巴细胞对胃腺癌细胞的生长代谢起明显的抑制作用。  相似文献   
996.
本文报道用原子吸收光谱、极谱和荧光法测定了吉林人参各部位中14种微量元素。结果表明,它们的含量各异,且因人参部位、种植地点不同而异;地上部分加和量均值接近地下部分,其中铁、铜、锌、锰、钴、钼、镍7种人体必需微量元素加和量均值,地上部分反高于地下部分;果肉和叶是人参值株中微量元素富集的敏感部位。  相似文献   
997.
目的了解膳食补充条斑紫菜(Porphyra yezoensis)对原发性高血压(EH)患者血管内皮功能的影响。方法采取随机、空白对照、交叉设计的方法,将36名EH患者〔男,24人,平均年龄(55.0±7.9)岁;女,12人,平均年龄(50.5±7.1)岁〕分为2组,观察膳食补充条斑紫菜(45g/d)28d后血清内皮素(ET)及一氧化氮(NO)水平的变化情况。结果2组受试者补充条斑紫菜后ET水平分别降低了(16.3±8.6)ng/L和(22.2±8.8)ng/L,(P<0.05)。血清亚硝酸盐/硝酸盐(NO2-/NO3-)浓度分别升高了(15.8±5.8)μmol/L和(12.7±9.2)μmol/L,(P<0.05);且膳食补充组与空白对照组相比,ET和NO水平的变化均具有统计学意义(P<0.05)。结论条斑紫菜能改善EH患者血管内皮功能,舒张血管,降低血压。  相似文献   
998.
目的:探讨转化生长因子-β1(TGF-β1)在横纹肌肉瘤肌源性分化中的作用。方法:采用细胞培养、逆转录多聚酶链式反应(RT-PCR)及免疫荧光染色观察TGF-β1对横纹肌肉瘤细胞系RD肌源性分化相关指标的影响,并用免疫组化SP法,检测49例横纹肌肉瘤组织中TGF-β1表达与肌球蛋白重链(MyHC)之间的相关性。结果:TGF-β1可明显抑制RD细胞肌球蛋白重链mRNA和蛋白的表达。用TGF-β1处理RD细胞后,肌球蛋白重链和肌节肌动蛋白(Sarcomeric-Actin)阳性着色细胞数明显下降(P<0.05)。MyoD1的表达在处理前后未见明显差异。横纹肌肉瘤组织中TGF-β1表达与肌球蛋白重链呈明显负相关(P<0.05)。结论:TGF-β1可抑制RD细胞的肌源性分化,这一作用可能不依赖于MyoD1的调节。TGF-β1信号传导通路可能与横纹肌肉瘤的肌源性分化受阻有关。  相似文献   
999.
1000.
AIMS: Hereditary non-polyposis colorectal cancer, thyroid medullary carcinoma, breast/ovarian cancer and gastric cancer/breast cancer syndrome are encountered in surgery. Some gastric cancer/breast cancer syndrome may be the result of a CDH1 germline mutation. This is the first report of CDH1 germline mutations gastric cancer/breast cancer syndrome in Chinese patients. METHODS: Peripheral blood from the proband, as well as, her first and second degree relatives was collected and CDH1 gene exon 1-16 mutations were screened. E-cadherin/beta-catenin proteins expression and histopathologic features were examined on gastric cancer/breast cancer tissues from the proband. RESULTS: A C-->T nucleotide substitution at exon 13 (mRNA 2200 locus, Accession number NM-004360) was found. This was a transition from GCC-->GCT in DNA sequence (Ala154Ala). Diffuse-type gastric cancer and infiltrating ductal breast carcinoma were present. Both tumours preserved E-cadherin/beta-catenin expression immunohistochemically. CONCLUSIONS: Familial cancer syndrome with diffuse-type gastric cancer/breast cancer proband in Chinese has a propensity of early onset during lifespan. No truncating or splice-site CDH1 mutations had been identified in this family. A silent nucleotide variation in exon 13 of the CDH1 gene may contribute to some forms of cancer susceptibility.  相似文献   
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