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991.
The newly synthesized naftopidil analogue HUHS1015 reduced cell viability in malignant pleural mesothelioma cell lines MSTO‐211H, NCI‐H28, NCI‐H2052, and NCI‐H2452, with the potential greater than that for the anticancer drugs paclitaxel or cisplatin at concentrations higher than 30 μM. HUHS1015 induced both necrosis and apoptosis of MSTO‐211H and NCI‐H2052 cells. HUHS1015 upregulated expression of mRNAs for Puma, Hrk, and Noxa in MSTO‐211H and NCI‐H2052 cells, suggesting HUHS1015‐induced mitochondrial apoptosis. HUHS1015 clearly suppressed tumor growth in mice inoculated with NCI‐H2052 cells. Taken together, the results of the present study indicate that HUHS1015 could be developed as an effective anticancer drug for treatment of malignant pleural mesothelioma.  相似文献   
992.
Radiofrequency ablation (RFA) is commonly used as a treatment for small hepatocellular carcinoma (HCC). Although several complications such as intraperitoneal bleeding are often observed after RFA, hepatic arterioportal fistula (APF) is a less frequently occurring complication. In this study, we describe two cases of APF caused by RFA, which was successfully occluded by an interventional approach. Case 1 involved a 68-year-old man with solitary HCC in segment VIII of the liver. Both contrast-enhanced computed tomography and color Doppler sonography indicated an APF between the anterosuperior branch of the right hepatic artery (A8) and the portal branch (P8). Concordant with these findings, digital subtraction angiography (DSA) revealed an APF in segment VIII of the liver. Subsequently, the APF was successfully occluded by transarterial embolization (TAE) using gelatin sponge particles. Case 2 involved a 67-year-old man with solitary HCC in segment VII of the liver. Although he developed obstructive jaundice because of hemobilia after RFA, it was improved by endoscopic nasobiliary drainage and the systemic administration of antibiotics. In addition, color Doppler sonography revealed a disturbed flow of the right branch of the portal vein. Similar to case 1, DSA showed an APF between A8 and P8. The APF was successfully embolized by TAE using microcoils. In conclusion, it appears that the formation of APF should be checked after RFA. It is preferable to treat RFA-induced APF promptly by an interventional approach to avoid secondary complications such as portal hypertension and liver dysfunction.Key words: Hepatocellular carcinoma, Radiofrequency ablation, Arterioportal fistula, Transarterial embolization  相似文献   
993.
Although chronic arsenic exposure is a well-known risk for cardiovascular disease and has a strong correlation with hypertension, the molecular pathogenesis underlying arsenic exposure-induced hypertension remains poorly understood. To delineate the pathogenesis, we examined changes in the mRNA levels of 2 angiotensin II Type I receptor (AT1R) subtypes, AT1AR and AT1BR, in a mouse aortic endothelial cell line, END-D. Quantitative real-time PCR analysis revealed significant increases in the mRNA levels of 2 AT1R subtypes, AT1AR and AT1BR following sodium arsenite (SA) treatment. Flow cytometry analysis revealed that SA increases the generation of reactive oxygen species (ROS) in a dose-dependent manner. In addition, western blot analysis revealed that SA enhances the phosphorylations of c-Jun N-terminal kinases (JNK) and activated protein 1 (AP-1). These phosphorylations were inhibited by N-acetylcysteine (NAC), an anti-oxidant. Finally, SA-induced AT1R expression was found to be prevented both by NAC and specific JNK inhibitor, SP6001325, strongly indicating that AT1R upregulation is a result of the ROS-mediated activation of the JNK signaling pathway. Taken together, our results indicate that arsenic indeed upregulates the AT1R expression, thus highlighting a role of arsenic-induced aberrant AT1R signaling in the pathogenesis of hypertension.  相似文献   
994.
995.
This study evaluated the in vitro activity of combinations of doripenem (DRPM) with aminoglycosides (tobramycin or amikacin) or fluoroquinolone (ciprofloxacin) against 92 isolates of Pseudomonas aeruginosa from 16 clinical facilities in 2004 in Japan. We also tested combination effect of other carbapenems (imipenem (IPM), meropenem, biapenem) with aminoglycosides or fluoroquinolone by checkerboard dilution methods. DRPM showed synergistic or additive effects with the aminoglycosides or the fluoroquinolone against 90% of the isolates. The combination of DRPM and aminoglycosides showed the strongest synergistic effects against IPM-intermediate resistant and IPM resistant strains among the tested combinations. These results suggested that combination of DRPM with aminoglycosides would be useful for the treatment of infections caused by P aeruginosa including IPM-resistant strains.  相似文献   
996.
A precise and convenient high-performance liquid chromatography (HPLC) method has been established to assay nilotinib in human plasma. Chromatographic separation of nilotinib was performed on a LiChrosphere(?)100 RP-18(e) column (250 mm×4.0 mm, 5 μm) using a mixture of acetonitrile and 0.01 M phosphate buffer (pH 3.0) (42 : 58, v/v) under isocratic conditions at a flow rate of 1.0 ml/min with ultraviolet (UV) detection at 266 nm. The calibration curve showed linearity at concentrations between 250 ng/ml and 5000 ng/ml (r(2)>0.999). The mean±S.D. absolute recovery of nilotinib from plasma was 99.2±3.3%. The coefficients of variation of both intra- and inter-day precision were below 9.1%. These results indicate that this new HPLC-based quantification may be useful for therapeutic drug monitoring of nilotinib to help manage treatment in patients with chronic myeloid leukemia in clinical practice.  相似文献   
997.
Small‐for‐size syndrome (SFSS), which is characterized by synthetic dysfunction and prolonged cholestasis, is a major cause of worse short‐term prognoses after living donor adult liver transplantation (LDALT). However, the risks of SFSS remain unclear. The aim of this study was to clarify the risks of SFSS, which were analysed in 172 patients who underwent LDALT for chronic liver disease. Graft types included left lobe with caudate lobe graft (n = 110) and right lobe graft (n = 62). Thirty‐four cases (24 with left lobe grafts and 10 with right lobe grafts) were determined as SFSS. SFSS developed even if the actual graft‐to‐recipient standard liver volume ratio was >40%. Logistic regression analysis revealed three independent factors associated with SFSS development in left and right lobe grafts: donor age, actual graft‐to‐recipient native liver volume ratio, and Child’s score. Donor age and actual graft‐to‐recipient native liver volume ratio may become predictive factors for SFSS development in left and right lobe grafts in patients undergoing LDALT.  相似文献   
998.
Oxidative stress has been implicated in cancer initiation and progression. Fbxw7 (also known as Fbw7, SEL-10, hCdc4, or hAgo) is the F-box protein subunit of an Skp1-Cul1-F-box (SCF)-type ubiquitin ligase complex that plays a central role in the degradation of oncoproteins such as c-Myc, c-Jun, Notch, and cyclin E. Fbxw7 is therefore thought to function as a tumor suppressor, and indeed the Fbxw7 gene is frequently mutated in many human malignancies. The Fbxw7 gene locus encodes three protein isoforms: Fbxw7α, Fbxw7β, and Fbxw7γ. Whereas Fbxw7α and Fbxw7γ are resident in the nucleus, Fbxw7β shows a cytoplasmic distribution suggestive of localization to the endoplasmic reticulum (ER). The specific function of Fbxw7β has remained unknown, however. We now show that Fbxw7β contains a putative transmembrane domain near its NH(2) -terminus, and topological analysis revealed that Fbxw7β is inserted in the ER membrane. Fbxw7β assembled with Skp1, Cul1, and Rbx1 to form an SCF complex, although the efficiency of this process appeared lower than that for Fbxw7α or Fbxw7γ. To explore the physiological role of Fbxw7β, we generated mice specifically lacking this isoform of Fbxw7. Although these animals did not exhibit any apparent abnormalities in development, primary cultures of neurons prepared from the mutant mice were more vulnerable to oxidative stress than were those prepared from wild-type mice. Conversely, overexpression of Fbxw7β rendered cells resistant to oxidative stress, without affecting sensitivity to ER stress or other apoptosis-inducing agents. Our results thus suggest that Fbxw7β contributes to the protection of cells from oxidative stress.  相似文献   
999.
1000.
Oral vaccines that elicit a mucosal immune response may be effective against human immunodeficiency virus type 1 (HIV-1) because its transmission occurs mainly at the mucosa. The aim of this study was to construct recombinant Lactobacillus for oral delivery of oral vaccines against HIV-1 and to evaluate their immunogenicity. A recombinant Lactobacillus acidophilus strain expressing the HIV-1 Gag on the bacterial cell surface was established by fusion with the signal peptide and anchor motif of a mucus binding protein (Mub) from L. acidophilus with or without coexpression of Salmonella enterica serovar Typhimurium flagellin (FliC) fused to a different Mub signal peptide and anchor. Using HEK293 cells engineered to express Toll-like receptor 5 (TLR5), the biological activity of FliC on the bacterial cell surfaces was determined. The surface-exposed flagellin retained its TLR5-stimulating activity, suggesting that the recombinant strain with Gag and FliC dual display might provide a different immunopotency than the strain expressing only Gag. The immunological properties of the recombinant strains were assessed by coculture with human myeloid dendritic cells (DCs). The heterologous antigens on the cell surface affected maturation and cytokine responses of DCs. Acquired immune responses were also investigated by intragastric immunization of mice. The enzyme-linked immunosorbent spot assay showed induction of gamma interferon-producing cells at local mucosa after immunization of mice with the Gag-producing strain. Meanwhile, the immunization with L. acidophilus displaying both Gag and FliC resulted in an increase of Gag-specific IgA-secreting cells. These results suggested that the Gag-displaying L. acidophilus elicited specific immune responses and the coexistence of FliC conferred an adjuvant effect on local IgA production.  相似文献   
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