首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2003篇
  免费   153篇
  国内免费   3篇
  2159篇
  2024年   2篇
  2023年   26篇
  2022年   28篇
  2021年   60篇
  2020年   30篇
  2019年   47篇
  2018年   66篇
  2017年   51篇
  2016年   81篇
  2015年   87篇
  2014年   112篇
  2013年   163篇
  2012年   175篇
  2011年   155篇
  2010年   102篇
  2009年   91篇
  2008年   125篇
  2007年   122篇
  2006年   105篇
  2005年   72篇
  2004年   69篇
  2003年   70篇
  2002年   64篇
  2001年   30篇
  2000年   31篇
  1999年   29篇
  1998年   15篇
  1997年   10篇
  1996年   9篇
  1995年   6篇
  1994年   4篇
  1993年   2篇
  1992年   15篇
  1991年   16篇
  1990年   11篇
  1989年   6篇
  1988年   7篇
  1987年   7篇
  1986年   5篇
  1985年   11篇
  1984年   8篇
  1983年   3篇
  1982年   4篇
  1981年   4篇
  1979年   4篇
  1976年   2篇
  1975年   4篇
  1974年   4篇
  1965年   1篇
  1962年   1篇
排序方式: 共有2159条查询结果,搜索用时 0 毫秒
81.

Background

Although sorafenib is accepted as the standard of care in advanced hepatocellular carcinoma (HCC), its therapeutic benefit is marginal. Here, we aimed to compare the efficacy and safety of sorafenib monotherapy (S-M) and sorafenib-based loco-regional treatments (S-LRTs) in advanced HCC.

Methods

From 2007 to 2012, 290 patients with advanced HCC (Barcelona Clinic Liver Cancer stage C) with S-M (n = 226) or S-LRTs (n = 64) were reviewed retrospectively. Survival outcomes and treatment-related toxicities between two groups were analyzed.

Results

Variables related to tumor burden and liver function were similar between the groups (all P > 0.05). Within the entire population, the S-LRTs group had both longer median overall survival (OS) (8.5 vs 5.5 months, P = 0.001) and progression-free survival (PFS) (5.3 vs 3.0 months, P = 0.002) than the S-M group. Furthermore, the S-LRTs group had longer Os than the S-M group in a subgroup with neither extrahepatic spread (EHS) nor regional nodal involvement (RNI) (18.0 vs 7.8 months, P = 0.019) and in a subgroup with EHS and/or RNI (8.3 vs 4.8 months, P = 0.028). In addition, the S-LRTs group had longer PFS than the S-M group in the subgroup with neither EHS nor RNI (9.6 vs 3.2 months, P = 0.027).

Treatment

Related toxicity was similar between two groups.

Conclusion

Combined use of sorafenib and LRTs may provide better treatment outcomes without significantly increasing treatment-related toxicities, even in patients with EHS and/or RNI. Therefore, addition of active LRTs might be considered, if feasible.  相似文献   
82.
Park SG  Kho CW  Cho S  Lee DH  Kim SH  Park BC 《Proteomics》2002,2(2):206-211
Here we describe a proteomic approach to detect fibrinolytic enzymes from the culture supernatant of Bacillus subtilis 168. Following isoelectric focusing without dithiothreitol, two gels, one for sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and the other for zymography, were run in parallel. After silver staining of SDS-PAGE and activity staining of zymography gel, the two gels were superimposed to detect protein spots that coincided with clear zones on the zymography gel. We identified four protein spots and characterized them with matrix-assisted laser desorption/ionization mass spectrometry. Database search revealed that four spots contained at least one of the extracellular serine proteases such as WprA and Vpr. This combined method of two-dimensional gel and zymography can be used as a powerful tool to detect proteases from various organisms.  相似文献   
83.
Highly conductive and ultrathin 2D nanosheets are of importance for the development of portable electronics and electric vehicles. However, scalable production and rational design for highly electronic and ionic conductive 2D nanosheets still remain a challenge. Herein, an industrially adoptable fluid dynamic exfoliation process is reported to produce large quantities of ionic liquid (IL)‐functionalized metallic phase MoS2 (m‐MoS2) and defect‐free graphene (Gr) sheets. Hybrid 2D–2D layered films are also fabricated by incorporating Gr sheets into compact m‐MoS2 films. The incorporated IL functionalities and Gr sheets prevent aggregation and restacking of the m‐MoS2 sheets, thereby creating efficient and rapid ion and electron pathways in the hybrid films. The hybrid film with a high packing density of 2.02 g cm?3 has an outstanding volumetric capacitance of 1430.5 F cm?3 at 1 A g?1 and an extremely high rate capability of 80% retention at 1000 A g?1. The flexible supercapacitor assembled using a polymer‐gel electrolyte exhibits excellent resilience to harsh electrochemical and mechanical conditions while maintaining an impressive rate performance and long cycle life. Successful achievement of an ultrahigh volumetric energy density (1.14 W h cm?3) using an organic electrolyte with a wide cell voltage of ≈3.5 V is demonstrated.  相似文献   
84.
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value.  相似文献   
85.
Hierarchical likelihood approach for frailty models   总被引:5,自引:0,他引:5  
  相似文献   
86.
87.
88.
The polyaniline (PANi)-Nafion composite film was prepared onto the ceramic plate by the cyclic voltammetry (CV) method with the various cycle numbers. When the PANi-Nafion/Au/ceramic plate with the preparing cycle number of 5 was as working electrode, the cathodic peak current was achieved as 84.0 microA in 60 mg dl(-1) NH4Cl buffer solution. On the other hand, the small cathodic peak currents for buffer solution in the presence of 60 mg dl(-1) LiOH, NaCl and KCl, respectively, were found with the same composite electrode as working electrode. The cathodic peak current decreased from 84.0 to 16.3 microA in the 60 mg dl(-1) NH4Cl buffer solution when the cycle number for preparing PANi-Nafion/Au/ceramic plate composite electrode with the CV method increased from 5 to 15. The enzyme of urease was immobilized onto the PANi-Nafion/Au/ceramic plate composite film by the electrochemical immobilization and the casting methods and used as sensing electrode to detect the concentration of urea in the buffer solution. The sensitivity of composite electrode immobilized with the casting method was greater than that of electrochemical immobilization method. The sensitivity and the detecting limit of the urea sensor were found to be 0.7 and 5.27 microA (mg dl(-1))(-1)cm(-2), as well as 6 and 0.3 mg dl(-1), respectively, when urease was immobilized by glutaraldehyde (GA) cross-linker and Nafion network, respectively.  相似文献   
89.
The Vero cell line, a non-phagocytic cell, has supported the intracellular mechanism of Leishmania (L.) chagasi. This strain (MHOM/BR/501/MS00) was isolated from a human case of visceral leishmaniasis in Mato Grosso do Sul, Brazil and cultivated in Schneider's Drosophila medium with 20% of heat inactivated fetal calf serum. It was allowed to infect the Vero cells at a ratio of 10 to 20 promastigotes per cell. Within six hours of incubation, promastigote forms were found attached to Vero cells without any particular orientation. The number of amastigotes per cell increased during the incubation period. Results showed that promastigotes of L. (L.) chagasi could interact, transform to amastigote forms and multiply in non-phagocytic cells, demonstrating a new model to study the intracellular cycle of this protozoan.  相似文献   
90.
Antiviral immunity requires recognition of viral pathogens and activation of cytotoxic and Th cells by innate immune cells. In this study, we demonstrate that hepatitis C virus (HCV) core and nonstructural protein 3 (NS3), but not envelope 2 proteins (E2), activate monocytes and myeloid dendritic cells (DCs) and partially reproduce abnormalities found in chronic HCV infection. HCV core or NS3 (not E2) triggered inflammatory cytokine mRNA and TNF-alpha production in monocytes. Degradation of I-kappa B alpha suggested involvement of NF-kappa B activation. HCV core and NS3 induced production of the anti-inflammatory cytokine, IL-10. Both monocyte TNF-alpha and IL-10 levels were higher upon HCV core and NS3 protein stimulation in HCV-infected patients than in normals. HCV core and NS3 (not E2) inhibited differentiation and allostimulatory capacity of immature DCs similar to defects in HCV infection. This was associated with elevated IL-10 and decreased IL-2 levels during T cell proliferation. Increased IL-10 was produced by HCV patients' DCs and by core- or NS3-treated normal DCs, while IL-12 was decreased only in HCV DCs. Addition of anti-IL-10 Ab, not IL-12, ameliorated T cell proliferation with HCV core- or NS3-treated DCs. Reduced allostimulatory capacity in HCV core- and NS3-treated immature DCs, but not in DCs of HCV patients, was reversed by LPS maturation, suggesting more complex DC defects in vivo than those mediated by core or NS3 proteins. Our results reveal that HCV core and NS3 proteins activate monocytes and inhibit DC differentiation in the absence of the intact virus and mediate some of the immunoinhibitory effects of HCV via IL-10 induction.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号