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981.
Vagal secretory nerves for pancreatic secretion in the rat   总被引:1,自引:0,他引:1  
  相似文献   
982.
目的:探讨体外反搏改善心肌缺血犬血流动力学的作用和内皮素机制。 方法: 19只健康杂种犬随机分为对照组、缺血组和反搏组,分别于冠状动脉左前降支结扎前和结扎后60 min、120 min、180 min记录以下指标:①主动脉根部血压;②左心室收缩和舒张末压、+dp/dtmax和-dp/dtmax;③头臂干血流量;④放免法检测血浆和心肌内皮素-1(ET-1)的含量。 结果: 冠脉结扎1 h,缺血组和反搏组犬血压、左心室收缩和舒张功能、头臂干血流量明显低于正常组(P<0.05),而血浆ET-1水平明显高于正常组(P<0.05)。经过体外反搏2 h,反搏组犬的收缩压、舒张压和平均压、左心室收缩和舒张功能、头臂干血流量明显高于缺血组(P<0.05);而反搏组犬的血浆和心肌ET-1水平明显低于缺血组(P<0.05)。 结论: 体外反搏可改善心肌缺血犬血流动力学指标,其机制可能与降低ET-1的产生有关。  相似文献   
983.
Yen JH  Tsai WC  Chen CJ  Lin CH  Ou TT  Hu CJ  Liu HW 《Immunology letters》2003,88(2):113-116
OBJECTIVES: To investigate the associations of cytochrome p450 1A1 (CYP1A1) and manganese superoxide dismutase (MnSOD) genes polymorphisms with the susceptibility to AS in Taiwan. METHODS: The polymorphisms of CYP1A1 and MnSOD genes were determined in 70 patients with ankylosing spondylitis (AS) and 93 healthy controls by polymerase chain reaction (PCR)/restriction fragment length polymorphisms (RFLP) methods. RESULTS: The genotype frequency of CYP1A1 4887C/A was significantly lower in patients with AS than in controls. The phenotype frequency of CYP1A1 4887A also tended to be decreased in patients with AS. There were no significant differences in the genotype, allele, and phenotype frequencies of MnSOD gene polymorphisms between patients with AS and controls. CONCLUSION: CYP1A1 4887A may be a protective factor for the development of AS in Taiwan. However, MnSOD gene polymorphisms are not associated with the susceptibility to AS.  相似文献   
984.
Nonmyelinated (C-) fibers represent the majority of vagal afferents innervating the airways and lung, and play an important role in regulating the respiratory and cardiovascular functions under both normal and abnormal physiologic conditions. Studies of the relationship between the conduction velocities of the vagal afferents and their sensitivities to capsaicin and other chemical irritants reveal that C-fibers are the primary type of chemosensitive afferents in the rat lung. Furthermore, a distinct sensitivity to capsaicin and a weak response to lung inflation are the defining characteristics of these afferents. In cultured rat nodose and jugular ganglion neurons, capsaicin-sensitive cells were identified by measurement of the capsaicin-evoked calcium transients using the Fura-2-based ratiometric imaging technique. The percentage of capsaicin-sensitive neurons gradually decreases as the cell diameter increases. However, the capsaicin-sensitive neurons cannot be precisely identified solely on the basis of the cell size. Anandamide, an endogenous cannabinoid released from leukocytes and epithelial cells, consistently evokes a stimulatory effect on pulmonary C-fiber endings by activating vanilloid receptor type 1 (VR1). The discharge pattern of pulmonary C-fibers evoked by anandamide closely resembles that produced by a much lower ( approximately 1/600) dose of capsaicin in the same fibers. Whether anandamide acts as a potential endogenous ligand to VR1 at the C-fiber terminals is unclear, and the physiological role of VR1 in modulating the transduction properties of these afferents also remains to be determined.  相似文献   
985.
目的:观察同型半胱氨酸(Hcy)对心肌线粒体电子漏及自由基生成的影响,以及观察牛磺酸的拮抗效应。方法: 分离大鼠心肌线粒体,超声波破碎线粒体制备亚线粒体,纯化制备猪心肌线粒体琥珀酸细胞色素C还原酶(SCR)重组体。分别用Hcy和/或牛磺酸共同孵育心肌线粒体、亚线粒体、SCR;用化学发光法测定H2O2- 及O2- 生成;并用滤膜抽滤法观察线粒体膜牛磺酸转运体的性质及Hcy对牛磺酸转运功能的影响。结果: Hcy呈浓度依赖性地刺激大鼠心肌线粒体、亚线粒体氧自由基生成及SCR电子漏增加,牛磺酸自身不影响心肌线粒体、亚线粒体及SCR氧自由基生成,但呈浓度依赖性地抑制Hcy诱导的线粒体、亚线粒体及呼吸链重组体氧自由基生成。线粒体膜上存在Na+依赖性的牛磺酸转运体,Hcy呈浓度依赖性地抑制牛磺酸转运体对牛磺酸的转运功能。结论: 牛磺酸抑制Hcy刺激的线粒体呼吸链电子漏增加及氧自由基生成。线粒体膜上存在Na+依赖性的牛磺酸转运体,Hcy抑制线粒体膜上牛磺酸转运体对牛磺酸的转运功能。  相似文献   
986.
BACKGROUND AND PURPOSE: Kawasaki disease (KD) is rare in infants < or =3 months of age. This study analyzed the features of KD in 25 infants < or =3 months of age treated from February 1994 to December 2004. METHODS: Basic characteristics, clinical, laboratory, echocardiographic, therapeutic, and follow-up data of the infants were obtained from chart records. RESULTS: There were 19 male and 6 female infants in this cohort. The frequency of the 5 principal clinical features was as follows: changes in lips and oral cavity, 84%; bilateral bulbar conjunctival injection without exudates, 80%; polymorphous exanthem, 68%; cervical lymphadenopathy, 28%; and changes in extremities, 24%. Six infants (24%) fulfilled criteria for KD including fever which persists for 5 or more days with at least 4 of the principal clinical criteria, and the remaining infants were classified as having incomplete KD (all of whom showed coronary involvement). Coronary artery dilatation was found in 20 infants (80%). One infant developed a medium-size aneurysm (5.2 mm), while the others had only coronary arterial ectasia or small aneurysms. Coronary artery aneurysms regressed within 1-year follow-up in all but one infant. No fatal or recurrent case was observed during the study period. CONCLUSIONS: Infants < or =3 months of age with KD usually presented with incomplete clinical features. A high proportion of coronary artery involvement was observed in this series. Echocardiography should be considered in very young infants with unexplained prolonged fever who do not present all of the principal clinical features of KD.  相似文献   
987.
988.
Genome-wide profiling of oral squamous cell carcinoma   总被引:7,自引:0,他引:7  
Oral squamous cell carcinoma (OSCC) is a common malignancy, the incidence of which is particularly high in some Asian countries due to the geographically linked areca quid (AQ) chewing habit. In this study, array-based comparative genomic hybridization was used to screen microdissected OSCCs for genome-wide alterations. The highest frequencies of gene gain were detected for TP63, Serpine1, FGF4/FGF3, c-Myc and DMD. The highest frequencies of deletion were detected for Caspase8 and MTAP. Gained genes, classified by hierarchical clustering, were mainly on 17q21-tel; 20q; 11q13; 3q27-29 and the X chromosome. Among these, gains of EGFR at 7p, FGF4/FGF3, CCND1 and EMS1 at 11q13, and AIB1 at 20q were significantly associated with lymph node metastasis. The genomic profiles of FHIT and EXT1 in AQ-associated and non-AQ-associated OSCCs exhibited the most prominent differences. RT-PCR confirmed the significant increase of TP63 and Serpine1 mRNA expression in OSCC relative to non-malignant matched tissue. A significant increase in Serpine1 immunoreactivity was observed from non-malignant matched tissue to OSCC. However, there was no correlation between the frequent genomic loss of Caspase 8 and a significant decrease in Caspase8 expression. These data demonstrate that genomic profiling can be useful in analysing pathogenetic events involved in the genesis or progression of OSCC.  相似文献   
989.
Dextran hydrogels were obtained by radical copolymerization of methacrylated dextran (MA-dextran) with acrylic acid (AAc) using ammonium peroxydisulfate (APS) and N,N,N',N'-tetramethylethylenediamine (TMEDA) as an initiation system in an aqueous solution. The AAc content in hydrogels was determined by FTIR. Copolymerization of MA-dextran with AAc increased the cross-linking density of hydrogels by the bridging effect of AAc and, to a certain extent, facilitated the formation of hydrogels from MA-dextran with a low degree of MA substitution (DS). For hydrogels with a low DS (5.9), the swelling at pH 7.4 initially decreased and then increased with increasing AAc. The swelling of hydrogels with high DS (11.4 and 22.4) increased gradually with AAc. This discrepancy was explained by the differences in the chemical potentials of water outside and inside of the hydrogels as a function of AAc. Further increases of AAc, however, led to a reduction in polymerization conversion and even incomplete formation of hydrogel. The reduction in polymerization yield was primarily a consequence of the pH reduction and salt formation of AAc with TMEDA.  相似文献   
990.
目的应用复合诱导突变分离PCR(multiplexed mutagenically separated PCR,MS-PCR)技术、银染分型,建立线粒体DNA(mitochondrial DNA,mtDNA)编码区单核苷酸多态(single nucleotide polymorphism,SNP)分型系统,探讨其应用价值。并调查了成都汉族群体mtDNA编码区4个SNP基因座等位基因频率和单倍型分布情况。方法根据SNP基因座(C12705T、A8701G、G8584A、C10400T)设计两条片段相差4个碱基的等位基因特异性引物和一条公共引物,4个SNP基因座复合扩增,PCR产物经聚丙烯酰胺凝胶电泳、银染显带后确定样本的基因型。结果不同SNP基因座为长度不同的单一谱带,其分型结果与直接测序一致。在成都汉族160名无关个体中,4个SNP基因座C12705T、A8701G、G8584A、C10400T等位基因频率分别为0.3813/0.6187、0.4813/0·5187、0.8250/0.1750、0.4938/0.5062;共检出6种单倍型,单倍型的基因多样性为0.7137。结论建立的MMS-PCR银染分型系统是一种简单、快速、准确、有效的SNP分型方法,对建立mtDNA编码区SNP数据库,研究群体遗传学、进化学和进行法医学个人识别和亲子鉴定有重要意义。  相似文献   
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