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991.
Neolithic patrilineal signals indicate that the Armenian plateau was repopulated by agriculturalists
Herrera KJ Lowery RK Hadden L Calderon S Chiou C Yepiskoposyan L Regueiro M Underhill PA Herrera RJ 《European journal of human genetics : EJHG》2012,20(3):313-320
Armenia, situated between the Black and Caspian Seas, lies at the junction of Turkey, Iran, Georgia, Azerbaijan and former Mesopotamia. This geographic position made it a potential contact zone between Eastern and Western civilizations. In this investigation, we assess Y-chromosomal diversity in four geographically distinct populations that represent the extent of historical Armenia. We find a striking prominence of haplogroups previously implicated with the Agricultural Revolution in the Near East, including the J2a-M410-, R1b1b1(*)-L23-, G2a-P15- and J1-M267-derived lineages. Given that the Last Glacial Maximum event in the Armenian plateau occured a few millennia before the Neolithic era, we envision a scenario in which its repopulation was achieved mainly by the arrival of farmers from the Fertile Crescent temporally coincident with the initial inception of farming in Greece. However, we detect very restricted genetic affinities with Europe that suggest any later cultural diffusions from Armenia to Europe were not associated with substantial amounts of paternal gene flow, despite the presence of closely related Indo-European languages in both Armenia and Southeast Europe. 相似文献
992.
Yang YP Chien Y Chiou GY Cherng JY Wang ML Lo WL Chang YL Huang PI Chen YW Shih YH Chen MT Chiou SH 《Biomaterials》2012,33(5):1462-1476
Glioblastomas (GBMs) are the most common primary brain tumors with poor prognosis. CD133 has been considered a putative marker of cancer stem cells (CSCs) in malignant cancers, including GBMs. MicroRNAs (miRNAs), highly conserved small RNA molecules, may target oncogenes and have potential as a therapeutic strategy against cancer. However, the role of miRNAs in GBM-associated CSCs remains mostly unclear. In this study, our miRNA/mRNA-microarray and RT-PCR analysis showed that the expression of miR145 (a tumor-suppressive miRNA) is inversely correlated with the levels of Oct4 and Sox2 in GBM-CD133+ cells and malignant glioma specimens. We demonstrated that miR145 negatively regulates GBM tumorigenesis by targeting Oct4 and Sox2 in GBM-CD133+. Using polyurethane-short branch polyethylenimine (PU-PEI) as a therapeutic-delivery vehicle, PU-PEI-mediated miR145 delivery to GBM-CD133+ significantly inhibited their tumorigenic and CSC-like abilities and facilitated their differentiation into CD133−-non-CSCs. Furthermore, PU-PEI-miR145-treated GBM-CD133+ effectively suppressed the expression of drug-resistance and anti-apoptotic genes and increased the sensitivity of the cells to radiation and temozolomide. Finally, the in vivo delivery of PU-PEI-miR145 alone significantly suppressed tumorigenesis with stemness, and synergistically improved the survival rate when used in combination with radiotherapy and temozolomide in orthotopic GBM-CD133+-transplanted immunocompromised mice. Therefore, PU-PEI-miR145 is a novel therapeutic approach for malignant brain tumors. 相似文献
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994.
Dissection of the internal carotid artery is an under-recognized cause of transient ischemic attack and cerebral vascular accident. Spontaneous dissections, in which no precipitating cause can be identified, occur infrequently. Endovascular intervention is an evolving treatment option in patients in whom anticoagulation therapy alone is not adequate, who are not suitable candidates for major surgery, or who have extremely distal dissections that are difficult to access. We report a case of successful endovascular stenting and coil application in a patient with spontaneous dissection of the distal cervical internal carotid artery with extension to its petrous portion and an accompanying pseudoaneurysm at the level of the skull base. 相似文献
995.
Wu RS Wu KC Yang JS Chiou SM Yu CS Chang SJ Chueh FS Chung JG 《Anticancer research》2011,31(6):2203-2208
Etomidate is an important tool in the arsenal of the emergency physician, and it has been used in a variety of scenarios for both intubation and procedural sedation. In the present study, we investigated the cytotoxicity of etomidate including induction of apoptosis, and levels of protein and gene expressions associated with apoptotic cell death in murine leukemia RAW264.7 cells in vitro. Cytotoxic and apoptotic responses to etomidate of RAW264.7 cells, including cell morphological changes and cell viability were examined and measured by phase-contrast microscopy and flow cytometric assay, respectively. Results indicated that etomidate increased apoptotic cell morphological changes and reduced cell viability in RAW264.7 cells. 4',6-Diamidino-2-phenylindole (DAPI) staining also showed that etomidate induced the formation of apoptotic bodies, a characteristic of apoptosis. Results from Western blotting indicated that etomidate enhanced the levels of cytochrome c, apoptosis-inducing factor (AIF), endonuclease G (Endo G), caspase-9, caspase-3 active form and Bax proteins, but it inhibited the expression of Bcl-xl, leading to apoptosis. DNA microarray assay indicated that etomidate increased the expression of 17 genes (LOC676175; Gm14636; 2810021G02Rik; Iltifb; Olfr1167; Ttc30b; Olfr766; Gas5; Rgs1; LOC280487; V1rd4; Hist1h2bc; V1rj3; Gm10366; Olfr192; Gm10002 and Cspp1) and reduced the expression of 15 genes: (Gm10152; Gm5334; Olfr216; Lcn9; Gm10683; Gm5100; Tdgf1; Cypt2; Gm5595; 1700018F24Rik; Gm10417; Maml2; Olfr591; Trdn and Apol7c). In conclusion, etomidate induced cytotoxic and apoptotic effects the in murine leukemia RAW264.7 cells in vitro. 相似文献
996.
997.
998.
The purpose of this study was to investigate the impact of MCP-1 and its receptor CCR2 gene polymorphisms on the susceptibility and clinicopathological characteristics of oral cancer, as well as the synergistic effect between these gene polymorphisms and well-known risk factors including alcohol, tobacco, and areca consumptions. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique for polymorphism analysis, 344 healthy controls and 216 oral cancer patients were recruited to reveal a significant association between V64I CCR2 gene polymorphism and oral cancer susceptibility. After adjusting for other confounders, individuals with GA (AOR=1.84; 95%CI=1.10-3.20) or at least one A allele (AOR=1.78; 95%CI=1.05-3.02) had a higher risk for oral cancer, compared to GG genotypes. Moreover, results also revealed that for subjects with GA or at least one A allele of V64I CCR2 gene polymorphism, those exposed to environmental risk factors possessed a significantly higher risk for oral cancer than those unexposed subjects. Therefore, genetic polymorphism of CCR2-64I may contribute to the susceptibility to oral cancer. 相似文献
999.
1000.
Chen LH Loong CC Su TL Lee YJ Chu PM Tsai ML Tsai PH Tu PH Chi CW Lee HC Chiou SH 《Biochemical pharmacology》2011,81(5):24-605
In a previous study, BO-1051, an N-mustard linked with a DNA-affinic molecule, was shown to target various types of cancer cell lines. In the present study, we aimed to investigate the cytotoxicity, as well as the underlying mechanism, of BO-1051. We found that BO-1051 simultaneously induced apoptosis and autophagy in hepatocellular carcinoma cell lines. DNA double strand breaks induced by BO-1051 activated the ATM signaling pathway and subsequently resulted in caspase-dependent apoptosis. When autophagy was inhibited in its early or late stages, apoptosis was significantly enhanced. This result indicated autophagy as a cytoprotective effect against BO-1051-induced cell death. We further inhibited ATM activation using an ATM kinase inhibitor or ATM-specific siRNA and found that while apoptosis was blocked, autophagy also diminished in response to BO-1051. We not only determined a signaling pathway induced by BO-1051 but also clarified the linkage between DNA damage-induced apoptosis and autophagy. We also showed that BO-1051-induced autophagy acts as a cytoprotective reaction and downstream target of the ATM-signaling pathway. This research revealed autophagy as a universal cytoprotective response against DNA damage-inducing chemotherapeutic agents, including BO-1051, cisplatin, and doxorubicin, in hepatocellular carcinoma cell lines. Autophagy contributes to the remarkable drug resistance ability of liver cancer. 相似文献