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991.

Background

Neuropathic pain is difficult to control and patient response to current treatment is often inadequate. Opioids have been widely used to treat a variety of pain states, but have several side effects. Endogenous opioids are clinically safe, but are not used for treatment because of rapid metabolism. However, in-vivo transfection of endogenous opioid genes could have a powerful and safe analgesic effect. The purpose of this study was to investigate the efficacy of proopiomelanocortin (POMC, a precursor of the endogenous opioid peptide β-endorphin) gene transfer by use of radial shock waves (RSWs) in a rat neuropathic pain model.

Methods

As a neuropathic pain model, we used the Bennett chronic constriction injury (CCI) method. Immediately after CCI induction, POMC plasmid was injected into the rats’ gastrocnemius muscle followed by exposure to RSW. Mechanical allodynia was measured for 4 weeks and dorsal root ganglion (DRG) neurons were sectioned and immunostained.

Results

β-Endorphin blood levels and the number of β-endorphin-immunoreactive (IR) muscle fibers increased over 28 days. β-Endorphin overexpression caused a decrease in the number of calcitonin gene-related peptide (CGRP)-IR DRG neurons and suppressed neuropathic pain induced by CCI without causing adverse side effects. The size-distribution pattern of CGRP-IR DRG neurons shifted from small to large cells in the CCI group; however, the number of both small and large CGRP-IR cells decreased in the POMC group.

Conclusion

POMC gene transfection alleviated allodynia and reduced CGRP expression in DRG neurons without adverse effects. CGRP is not produced in large neurons under physiologic conditions; however, in this study CGRP expression was shifted to large neurons after nerve injury. This change in cell-size distribution suggests that CGRP expression in large neurons is related to neuropathic pain. These findings suggest that POMC gene transfection using RSWs is a safe and effective treatment for neuropathic pain.  相似文献   
992.
Since it has been shown in a previous study that aspartic acid prevents the development of physical dependence on and tolerance to morphine and antagonizes the abstinence syndrom signs, the biochemical bases of that prevention were investigated in the present study. The brain contents of serotonin, DA, NA, and free amino acids of the rats given aspartic acid and morphine separately and in combination were determined. It has been observed that most of the morphine-induced changes in the brain were normalized in the group given aspartic acid and morphine together. The relative ineffectiveness of aspartic acid in normalizing some amino acid levels decreased by morphine was discussed and some logical explanations were found.  相似文献   
993.
 背景:目前,尽管利用各种材料制备的组织工程化骨研究取得了一定进展,但均表现出诸如支架材料降解速度与新生骨组织形成速率不匹配、组织生长缓慢、降解代谢产物有毒性等缺陷。目的:构建一种新型的仿骨结构诱导性骨组织工程支架材料,评价其物理化学及生物学性能。方法:以壳聚糖包被淫羊藿苷制备微球,检测其体外缓释效果;将载药微球与胶原蛋白复合构建支架材料的管芯;将羟基磷灰石、聚己内酯与胶原蛋白依次以0∶3∶3、1∶3∶3、2∶3∶3、3∶3∶3的比例混合于六氟异丙醇中,通过静电纺丝技术依次电纺制得具有4层结构的支架材料外管;以1%京尼平将经嵌套的管芯与外管交联在一起。利用万能材料试验机、表面接触角仪、红外光谱、扫描电镜、吸水率、透气性、孔隙率、体外降解实验等对交联前后外管材料的结构和特征进行表征,并评价骨髓间充质干细胞与外管材料的生物相容性;Wistar大鼠皮下埋置实验进一步评价交联前后外管材料的组织相容性。结果与结论:药物在管芯中具有良好的缓释效果;制备的骨组织工程支架材料具有良好的均一性,交联后外管材料的力学性能、吸水率、透气性均高于未交联组(P < 0.05),且体外降解速率显著低于未交联组(P < 0.05)。苏木精-伊红染色显示骨髓间充质干细胞可良好贴附于交联前后的外管材料上;交联的外管材料植入Wistar大鼠皮下后均无炎症反应。表明交联后诱导性骨组织工程支架材料具有良好的生物相容性及力学性能。中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程  相似文献   
994.
We discuss a case of a 67‐year‐old male with dementia with Lewy bodies (DLB) that was initially suspected as Creutzfeldt–Jakob disease (CJD) or another type of encephalopathy, because he showed rapidly progressive deterioration, myoclonus, gait disturbance and a decline in activities of daily living. The present study describes a clinically atypical case with probable DLB and reviews similar cases in the literature, and we propose a rapidly progressive clinical subtype of DLB.  相似文献   
995.
护理排班模式改革探讨   总被引:22,自引:5,他引:22  
目的 探讨高效、全程优质服务的护理排班模式。方法 在原有人力基础上 ,改变人力结构 ,实施全夜制 (9PM~ 9AM ) ,2 4h分 3个班次 ,并增设护理骨干值二线班。结果 与传统式比较 ,护士交班、书写次数明显减少 ,抢救病人成功率从 2 5 %提高到 67% ,病人满意度从 94.5 %提高到 10 0 % (P <0 .0 5 )。结论 护理排班模式改革后 ,加强了中午、晚上的薄弱环节 ,为抢救赢得了时间 ,护士业务方面又起到互补互相促进作用  相似文献   
996.
近年来,HBV对肝癌细胞生物学行为的影响受到越来越多的关注.我们前期研究结果表明乙型肝炎病毒X蛋白(HBx)可以诱导肝癌细胞株SMMC-7721发生上皮-间质样表型转化(EMT),并显著增强肝癌细胞侵袭转移潜能[1].  相似文献   
997.
IntroductionAlthough genetic variants of the A disintegrin and metalloproteinase 10 (ADAM10) gene have been shown to be associated with susceptibility to several inflammatory-related diseases, to date little is known about the clinical relationship in the development of sepsis.MethodsTwo genetic variants in the promoter of ADAM10 were selected to analyze the potential association with the risk of sepsis. A total of 440 sepsis patients and 450 matched healthy individuals in two independent Chinese Han population were enrolled. Pyrosequencing and polymerase chain reaction-length polymorphism was used to determine the genotypes of the rs514049 and rs653765. A real-time qPCR method was used to detect the mRNA level of ADAM10. Enzyme-linked immunosorbent assay was used to measure the expression levels of substrates CX3CL1, interleukin (IL)-6R, tumor necrosis factor alpha (TNF-α), and the pro-inflammatory cytokines IL-1β and IL-6. Luciferase assay was used to analyze the activities of the promoter haplotypes of ADAM10.ResultsNo statistically significant differences between sepsis cases and controls in the genotype or allele frequencies were observed, suggesting that ADAM10 single nucleotide polymorphisms (SNPs) may not be risk factors for the occurrence of sepsis. A significant difference in the genotype and allele frequencies of the rs653765 SNP between patients with sepsis subtype and severe sepsis (P = 0.0014) or severe sepsis/sepsis shock (P = 0.0037) were observed. Moreover, the rs653765 CC genotype in severe sepsis showed a higher ADAM10 level compared to healthy groups, and the rs653765 CC polymorphism had a strong impact on the production of the ADAM10 substrates CX3CL1, IL-6R and TNF-α. Furthermore, the functional assay showed that ADAM10 C-A haplotype carriers exhibited significantly higher reporter activity compared with the T-A carriers and T-C carriers in human acute monocytic leukemia cell line.ConclusionsOur data initially indicated the ADAM10 rs653765 polymorphism was associated with the development of severe sepsis; the risk CC genotype could functionally affect the expression level of ADAM10 mRNA and was accompanied by the up-regulation of its substrates. Thus, ADAM10 might be clinically important and play a critical role in the pathogenesis of the development of sepsis, with potentially important therapeutic implications.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0796-x) contains supplementary material, which is available to authorized users.  相似文献   
998.
A prospective randomized clinical trial assessed the efficacy and tolerance of micafungin compared with that of standard fluconazole treatment in patients undergoing hematopoietic stem cell transplantation (HSCT). Adult patients (n = 106) were randomly assigned to receive prophylaxis with either micafungin 150 mg (n = 52), or fluconazole 400 mg (n = 52). Success was defined as the absence of suspected, proven, or probable invasive fungal infection (IFI) through the end of therapy and the absence of proven or probable IFI through the end of the 4-week period following treatment. The overall efficacy of micafungin was comparable to that of fluconazole (94 vs. 88%; difference 6.0%; 95% confidence interval, −5.4 to +17.4%; P = 0.295). A total of 2 (4.0%) of 50 patients in the micafungin arm and 6 (12.0%) of 50 patients in the fluconazole arm received empirical antifungal therapy (P = 0.06). Micafungin treatment did not result in increasing adverse effects and had a safe profile as fluconazole in neutropenic patients. This randomized trial indicates that the efficacy and tolerance of micafungin 150 mg was comparable to that of fluconazole 400 mg, suggesting that micafungin at 150 mg daily represents a valuable new treatment option for antifungal prophylaxis in HSCT recipients.  相似文献   
999.
Pre‐emptive cancer immunotherapy by donor lymphocyte infusion (DLI) using cytokine‐induced killer (CIK) cells may be beneficial to prevent relapse with a reduced risk of causing graft‐versus‐host‐disease. CIK cells are a heterogeneous effector cell population including T cells (CD3+ CD56?), natural killer (NK) cells (CD3?CD56+) and natural killer T (T‐NK) cells (CD3+ CD56+) that exhibit non‐major histocompatibility complex (MHC)‐restricted cytotoxicity and are generated by ex vivo expansion of peripheral blood mononuclear cells in the presence of interferon (IFN)‐γ, anti‐CD3 antibody, interleukin‐2 (IL‐2) and interleukin‐15 (IL‐15). To facilitate selective target‐cell recognition and enhance specific cytotoxicity against B‐cell acute lymphoblastic leukemia (B‐ALL), we transduced CIK cells with a lentiviral vector encoding a chimeric antigen receptor (CAR) that carries a composite CD28‐CD3ζ domain for signaling and a CD19‐specific scFv antibody fragment for cell binding (CAR 63.28.z). In vitro analysis revealed high and specific cell killing activity of CD19‐targeted CIK/63.28.z cells against otherwise CIK‐resistant cancer cell lines and primary B‐ALL blasts, which was dependent on CD19 expression and CAR signaling. In a xenograft model in immunodeficient mice, treatment with CIK/63.28.z cells in contrast to therapy with unmodified CIK cells resulted in complete and durable molecular remissions of established primary pre‐B‐ALL. Our results demonstrate potent antileukemic activity of CAR‐engineered CIK cells in vitro and in vivo, and suggest this strategy as a promising approach for adoptive immunotherapy of refractory pre‐B‐ALL.  相似文献   
1000.
SIRT6 is an important member of sirtuin family that represses inflammation, aging and DNA damage, three of which are causing factors for endothelial dysfunction. SIRT6 expression is decreased in atherosclerotic lesions from ApoE−/− mice and human patients. However, the role of SIRT6 in regulating vascular endothelial function and atherosclerosis is not well understood. Here we show that SIRT6 protects against endothelial dysfunction and atherosclerosis. Global and endothelium-specific SIRT6 knockout mice exhibited impaired endothelium-dependent vasorelaxation. Moreover, SIRT6+/− haploinsufficient mice fed a high-fat diet (HFD) also displayed impaired endothelium-dependent vasorelaxation. Importantly, SIRT6+/−;ApoE−/− mice after HFD feeding exhibited exacerbated atherosclerotic lesion development, concurrent with increased expression of the proinflammatory cytokine VCAM-1. Loss- and gain-of-SIRT6 function studies in cultured human endothelial cells (ECs) showed that SIRT6 attenuated monocyte adhesion to ECs. RNA-sequencing profiling revealed that SIRT6 overexpression decreased the expression of multiple atherosclerosis-related genes, including proatherogenic gene TNFSF4 (tumor necrosis factor superfamily member 4). Chromatin immunoprecipitation assays showed that SIRT6 decreased TNFSF4 gene expression by binding to and deacetylating H3K9 at TNFSF4 gene promoter. Collectively, these findings demonstrate that SIRT6 play a pivotal role in maintaining endothelial function and increased SIRT6 activity could be a new therapeutic strategy to combat atherosclerotic disease.  相似文献   
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