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101.
目的评价FRⅢ型功能调节器治疗安氏Ⅲ类错的效果。方法选择15例替牙期或恒牙早期安氏Ⅲ类错畸形患者,戴用FRⅢ型功能调节器6~12月,观察口腔发育状况,对矫治前后软硬组织变化行X线头影测量分析。结果患者均取得满意疗效。代表上下颌骨位置关系的SNA、SNB、NP-FH矫治前后改变有统计学意义(P﹤0.05);ANB、U1-SN、L1-MP矫治前后改变有高度统计学意义(P﹤0.01);鼻唇角趋于正常,软组织外貌得到改善。结论 FRⅢ型功能调节器对替牙期及恒牙初期安氏Ⅲ类错畸形有较好的疗效。  相似文献   
102.
Sirtinol, a cell permeable six-membered lactone ring, is derived from naphthol and potent inhibitor of SIR2 and its naphtholic may have the inhibitory effects on platelets aggregation. In this study, platelet function was examined by collagen/epinephrine (CEPI) and collagen/ADP-induced closure times using the PFA-100 system reveal that CEPI-CT and CADP-CT were prolonged by sirtinol. The platelets aggregation regulated by physiological agonists such as: thrombin, collagen and AA and U46619 were significantly inhibited by sirtinol. Increases cAMP level was observed when sirtinol treated with Prostaglandin E1 in washed platelets. Moreover, sirtinol attenuated intracellular Ca2+ release and thromboxane B2 formation stimulated by thrombin, collagen, AA and U46619 in human washed platelets. This study indicated that sirtinol could inhibit the platelet aggregation induced by physiological agonists, AA and U46619. The mechanism of action may include an increase of cAMP level with enhanced VASP-Ser157 phosphorylation via inhibition of cAMP phosphodiesterase activity and subsequent inhibition of intracellular Ca2+ mobilization, thromboxane A2 formation, and ATP release during the platelet aggregation.  相似文献   
103.
目的 探讨中国汉族人群中G蛋白信号调节因子5(RGS5)和ATP1B1基因功能区标签单核苷酸多态性(SNP)与原发性高血压的相关性及变异位点间的交互作用。方法 选择启动子、外显子和3’UTR区符合最小等位基因频率在中国北京汉族人群中>5%、R2≥0.80的SNP。对906例原发性高血压患者(EH组)进行SNP位点的基因分型,以性别和年龄与EH组匹配的894名血压正常者作为正常对照组。观察不同基因型和等位基因频率在EH组和对照组中的分布,并采用MDR软件分析各位点之间的交互作用。结果 最终3个标签SNP入选。EH组与对照组SNP位点基因型分布和等位基因频率比较差异无统计学意义(P>0.05);由2个基因SNP位点组成的单倍型,在EH组和对照组的分布比较差异也无统计学意义(P>0.05)。交互作用分析显示,2个或3个位点模型比较差异均无统计学意义(P>0.05)。结论 3个标签SNP与EH无明显相关性,并且可能不存在交互作用。  相似文献   
104.
目的探讨白藜芦醇(Res)对动脉粥样硬化兔心肌组织线粒体途径凋亡的影响。方法健康雄性新西兰白兔70只,随机分为5组:正常组、病理对照组、病理+低剂量Res组(4 mg·kg^-1·d^-1),病理+中剂量Res组(8 mg·kg^-1·d^-1)、病理+高剂量Res组(16 mg·kg^-1·d^-1)。分笼饲养12周后,取左心室尖部心肌组织。H-E染色观察心肌组织形态学改变,原位末端标记法检测心尖部细胞凋亡率,半定量RT-PCR检测bax、bcl-2的mRNA变化。结果H-E染色下各组细胞形态学改变不明显;病理对照组细胞凋亡指数高于正常组(P〈0.01)和Res干预组(P〈0.01),Res作用下凋亡指数下降呈剂量依赖性(P〈0.05);病理对照组bax、bcl-2mRNA表达量较正常组升高(P〈0.01),而加入Res干预后,bax的表达量明显下降,bcl-2表达升高(P〈0.01)。结论Res可以减少促凋亡基因bax的表达,增加抗凋亡基因bcl-2的表达,降低Bax/bcl-2比值,抑制心肌细胞的凋亡。  相似文献   
105.
There has been an increased demand for the development of novel vaccine adjuvants that lead to enhanced induction of protection from infectious challenges and development of immunological memory. A novel vaccine adjuvant was developed comprising a complex containing CpG oligonucleotide and the synthetic cationic innate defence regulator peptide HH2 that has enhanced immune modulating activities. The complex of HH2 and the CpG oligonucleotide 10101 was a potent inducer of cytokine/chemokine expression ex vivo, retained activity following extended storage, had low associated cytotoxicity, and upregulated surface marker expression in dendritic cells, a critical activity for a vaccine adjuvant. Immunization of mice with a coformulation of the HH2–CpG complex and pertussis toxoid significantly enhanced the induction of toxoid-specific antibody titres when compared to toxoid alone, inducing high titres of IgG1 and IgG2a, typical of a balanced Th1/Th2 response, and also led to high IgA titres.  相似文献   
106.
This study investigated the effect and mechanism of cell cycle reentry induced by 6-hydrodopamine (6-OHDA) in PC12 cells. By using neural differentiated PC12 cells treated with 6-OHDA, the apoptosis model of dopaminergic neurons was established. Cell viability was measured by MTT. Cell apoptosis and the distribution of cell cycle were assessed by flow cytometry. Western blot was used to detect the activation of extracellular regulator kinasel/2 (ERK1/2) pathway and the phosphorylation of retinoblastoma protein (RB). Our results showed that after PC12 cells were treated wtih 6-OHDA, the viability of PC12 cells was declined in a concentration-dependent manner. Flow cytornetry revealed that 6-OHDA could increase the apoptosis ratio of PC12 cells in a time-dependent manner. The percentage of ceils in G0/G1 phase of cell cycle was decreased and that in S phase and G2/M phase increased. Simultaneously, ERK1/2 pathway was activated and phosphorylated RB increased. It was concluded that 6-OHDA could induce cell cycle reentry of dopaminergic neurons through the activation of ERK1/2 pathway and RB phosphorylation. The aberrant cell cycle reentry contributes to the apoptosis of dopaminergic neurons.  相似文献   
107.
目的:探讨白藜芦醇可否通过SIRT1激活解整合素金属蛋白酶10(ADAM10)促进APPα代谢抑制Aβ分泌。方法:选取过表达人瑞典突变淀粉样前体蛋白APP695sw的细胞模型,分别设立DMSO空白对照组、SIRT1激活剂白藜芦醇组和SIRT1抑制剂EX527组。给药后,ELISA法分别检测细胞培养上清中sAPPα和Aβ的含量,免疫印记Western Blot法检测细胞SIRT1和ADAM10的蛋白水平。结果:与对照组比较,白藜芦醇组细胞培养上清sAPPα的含量增高,Aβ含量下降,sAPPα/Aβ比值增大,细胞SIRT1和ADAM10蛋白水平增高;而抑制剂EX527组与对照相比,细胞培养上清sAPPα的含量降低,Aβ含量升高,sAPPα/Aβ比值减小,细胞SIRT1和ADAM10蛋白水平降低;抑制剂下调SIRT1后各项指标与激动剂组呈现相反的趋势(P<0.05)。结论:白藜芦醇可通过SIRT1激活ADAM10,促进APP进行α非淀粉样代谢途径,增强sAPPα分泌并抑制Aβ产生。  相似文献   
108.
We aimed to compare the expression and function of molecular components of the RhoA/Rho-kinase signaling pathway in the contractile responses of detrusor, trigonal and urethral smooth muscle, using selective Rho-kinase inhibitors. Contractility studies and molecular approaches were employed to demonstrate the expression patterns and functional activity of the RhoA/Rho-kinase signaling pathway in the lower urinary tract. Frequency-response curves (1-32 Hz) and concentration-response curves (CRC) to carbachol (CCh, 0.01-30 microM), phenylephrine (PE, 0.01-300 microM) and endothelin-1 (ET-1, 0.01-100 nM) were significantly attenuated (p<0.01) following incubation with the Rho-kinase inhibitors H-1152 (0.1-1 microM), Y-27632 (1-10 microM) or HA-1077 (10 microM). Addition of Rho-kinase inhibitors also markedly reduced (p<0.01) the contractions evoked by either KCl (80 mM) or alpha,beta-methylene ATP (alpha,beta-mATP, 10 microM). Among the Rho-kinase inhibitors tested, H-1152 was approximately 9-16 times more potent than Y-27632 or HA-1077. In addition, basal tone of detrusor and trigonal strips was reduced following addition of Y-27632 (10 microM), H-1152 (1 microM) and HA-1077 (10 microM). The expression of RhoA, RhoGDI, leukemia-associated RhoGEF (LARG) and p115RhoGEF was similar among the detrusor, trigone and urethra, whereas Rho-kinase alpha, Rho-kinase beta and PDZ-RhoGEF protein levels were significantly lower in the urethra. Components of the RhoA/Rho-kinase signaling are expressed in detrusor, trigonal and urethral smooth muscle and dynamically regulate contraction and tone. Manipulation of RhoGEF expression may provide further understanding of mechanisms involving Ca(2+) sensitization in the lower urinary tract.  相似文献   
109.
In cystic fibrosis (CF) patients, pulmonary inflammation is a major cause of morbidity and mortality and may precede bacterial colonization. The aim of the present study was to investigate the molecular mechanisms underlying intrinsic inflammation in cystic fibrosis airways. Using different cystic fibrosis cell models, we first demonstrated that, beside a high constitutive nuclear factor of kappaB (NF-kappaB) activity, CF cells showed a higher activator protein-1 (AP-1) activity as compared to their respective control cells. Gene expression profiles, confirmed by RT-PCR and ELISA, showed over-expression of numerous NF-kappaB and AP-1-dependent pro-inflammatory genes in CF cells in comparison with control cells. Activation of NF-kappaB was correlated with higher inhibitor of kappaB kinase (IKK) activity. In addition, Bio-plex phosphoprotein assays revealed higher extracellular signal-regulated kinase (ERK) phosphorylation in CFT-2 cells. Inhibition of this kinase strongly decreased expression of pro-inflammatory genes coding for growth-regulated proteins (Gro-alpha, Gro-beta and Gro-gamma) and interleukins (IL-1beta, IL-6 and IL-8). Moreover, inhibition of secreted interleukin-1beta (IL-1beta) and basic fibroblast growth factor (bFGF) with neutralizing antibodies reduced pro-inflammatory gene expression. Our data thus demonstrated for the first time that the absence of functional cystic fibrosis transmembrane conductance regulator (CFTR) at the plasma membrane leads to an intrinsic AP-1, in addition to NF-kappaB, activity and consequently to a pro-inflammatory state sustained through autocrine factors such as IL-1beta and bFGF.  相似文献   
110.
Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in signal transduction pathways that are initiated at sites of integrin-mediated cell adhesions and by growth factor receptors. FAK is a key regulator of survival, proliferation, migration and invasion: processes that are all involved in the development and progression of cancer. FAK is also linked to oncogenes at both a biochemical and functional level. Moreover, overexpression and/or increased activity of FAK is common in a wide variety of human cancers, implicating a role for FAK in carcinogenesis. Given the important role of FAK in a large number of processes involved in tumorigenesis, metastasis and survival signalling FAK should be regarded as a potential target in the development of anti-cancer drugs. Therefore, selective inhibitors of FAK need to be developed. Combination of these selective FAK inhibitors with cytotoxic agents could be a very promising anti-cancer therapy.  相似文献   
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