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991.
依那普利治疗原发性高血压对血浆NO、vWF的影响   总被引:1,自引:0,他引:1  
目的:评价依那普利治疗轻、中度原发性高血压对一氧化氮(NO)、内皮血管性血友病因子(vWF)的影响。方法:选取轻、中度原发性高血压患者45例及正常对照组30例,原发性高血压组服用依那普利20mg/d,分别对治疗前、治疗16周后及正常对照组行血浆NO、vWF检测。结果:治疗前血浆NO较正常对照组降低(P<0.05),治疗后血浆NO较治疗前明显升高(P<0.01)。治疗前血浆vWF较正常对照组明显升高(P<0.01),治疗后血浆vWF较治疗前降低(P<0.05)。结论:依那普利明显升高血浆NO、降低vWF,说明它在降压的同时具有保护血管内皮细胞的功能。  相似文献   
992.
The regional distribution of inflammation during acute lung injury (ALI) is not well known. In an ovine ALI model we studied regional alveolar inflammation, surfactant composition, and CT-derived regional specific volume change (sVol) and specific compliance (sC). 18 ventilated adult sheep received IV lipopolysaccharide (LPS) until severe ALI was achieved. Blood and bronchoalveolar lavage (BAL) samples from apical and basal lung regions were obtained at baseline and injury time points, for analysis of cytokines (IL-6, IL-1β), BAL protein and surfactant composition. Whole lung CT images were obtained in 4 additional sheep. BAL protein and IL-1β were significantly higher in injured apical vs. basal regions. No significant regional surfactant composition changes were observed. Baseline sVol and sC were lower in apex vs. base; ALI enhanced this cranio-caudal difference, reaching statistical significance only for sC. This study suggests that apical lung regions show greater inflammation than basal ones during IV LPS-induced ALI which may relate to differences in regional mechanical events.  相似文献   
993.
研究兔骨髓间充质干细胞(BMSCs)经超顺磁性氧化铁(SPIO)标记后,体外成骨、成脂及成软骨诱导能力的变化。体外贴壁培养和扩增兔BMSCs,采用SPIO(25μg/ml)联合硫酸鱼精蛋白转染剂标记兔BMSCs,分别采用适宜的成骨、成脂及成软骨诱导培养液对磁标记BMSCs进行体外定向诱导培养3周,诱导过程中观察细胞形态学变化。3周后对成骨定向诱导组进行钙结节茜素红染色和碱性磷酸酶(ALP)组化染色;对成脂肪定向诱导组行油红-O染色;对成软骨定向诱导组行番红O染色、II型胶原免疫组化染色检测观察胞外基质糖胺多糖、II型胶原的分泌和表达。利用Image-Pro Plus图像分析系统对免疫细胞化学染色进行光密度半定量分析。结果表明:超顺磁性氧化铁粒子标记BMSCs后普鲁士染色和电镜检查显示细胞胞浆内含致密铁颗粒;磁标记BMSCs在成骨、成脂及成软骨潜在多向分化诱导能力上与对照组未标记细胞相比无统计学差异。提示,SPIO联合硫酸鱼精蛋白转染剂能成功标记BMSCs,超顺磁性氧化铁标记对兔BMSCs体外多向分化诱导能力无明显影响,合理应用这种新型细胞标记技术将促进对组织工程种子细胞的研究。  相似文献   
994.
目的 探讨一氧化氮合酶1(nitric oxide synthase 1,NOS1)基因多态性与精神分裂症易感性的相关性.方法 选取NOS1区域的28个标签单核苷酸多态性(single nucleotide polymorphisms,SNPs)位点,应用Illumina GoldenGate定制芯片对382例汉族精神分裂症患者和448名正常人的DNA进行分型,并分析其与精神分裂症的相关性.结果 单位点分析提示SNP位点rs1520811与精神分裂症存在关联,但是经过Bonferroni多重校正后差异无统计学意义(P>0.05).单体型分析未发现单体型与精神分裂症的相关性.结论 未证实NOS1为精神分裂症的易感基因.  相似文献   
995.
目的 研究慢性乙型肝炎(CHB)患者经干扰素治疗前后外周血CD4+T细胞上可诱导共刺激分子( inducible costimulator,ICOS)表达水平的变化情况.方法 CHB患者56例,其中聚乙二醇(PEG)干扰素α2a治疗28例,拉米夫定治疗28例,以健康志愿者20例为正常对照组.采集两治疗组治疗前及治疗后24、48周的患者外周血,以流式细胞技术检测ICOS+ CD4+T细胞在外周血单个核细胞(peripheral blood mononuclear cells,PBMC)中的频数变化;采用real-time PCR法检测患者HBV DNA载量变化.结果 CHB患者CD4+T细胞ICOS表达水平明显高于正常对照者(P<0.001).干扰素治疗后患者ICOS表达水平下降,同拉米夫定组差异有统计学意义(P<0.05).干扰素治疗后患者ICOS改变值同HBV DNA载量变化值呈正相关(r=0.972,P<0.001),而拉米夫定组则未发现相关性(r=-0.101,P=0.608).结论 CHB患者存在着细胞免疫紊乱,其CD4+T细胞ICOS的表达升高.干扰素可下调CD4+T细胞ICOS的表达,纠正细胞免疫偏移,发挥抗HBV作用.  相似文献   
996.
目的 研究超顺磁氧化铁(SPIO)标记对大鼠脂肪干细胞(ADSCs)向肝样细胞诱导分化的影响.方法 0.25%Ⅱ型胶原酶消化SD大鼠脂肪组织,获取原代ADSCs.采用多聚赖氨酸(PLL)介导SPIO(25 μg/ml)标记ADSCs,以肝细胞生长因子(HGF)作为主要诱导因子,分成标记-诱导组、未标记-诱导组、标记-未诱导组及未标记-未诱导组,后2组分别作为对照.光学显微镜检测标记细胞内的铁摄取.台盼兰染色评价ADSCs的细胞活力.SPIO标记-诱导组和未标记-诱导组细胞均向肝样细胞诱导分化.分别在诱导前、诱导后7、14、21d糖原染色分析肝样细胞内糖原储存;免疫细胞化学染色和RT-PCR分析肝样细胞内白蛋白(ALB)的表达.结果 ADSCs胞浆内铁标记率为100%.SPIO标记组与未标记组的细胞活力差异无统计学意义(P>0.05).标记诱导组与未标记诱导组在诱导后14d细胞胞浆糖原染色均为阳性;诱导21d后,2组细胞胞浆内染色阳性的细胞增多.14、21 d ALB mRNA和蛋白表达水平逐渐增强.结论 SPIO标记对大鼠ADSCs的生长及其向肝样细胞诱导分化无明显影响.  相似文献   
997.
The airflow and gas exchange behaviors of the human maxillary sinus were quantified to better understand the effect of an accessory ostium (AO). An anatomically correct numerical domain was constructed using CT data from a male patient with mild nasal obstruction. For the purpose of comparison, a numerical model without an AO was also generated by artificially removing the AO from the original model using CAD software. A steady-flow field through the nasal cavity was simulated using ANSYS-FLUENT v13.0 with a target flow rate of 250 ml/s. The Volume of Fluid (VOF) method was used to investigate the concentration field of nitric oxide (NO) initially filled in the maxillary sinus. The simulation results showed that a transit flow through the maxillary sinus developed in the presence of an AO. As the flow entered the sinus through either a natural or accessory ostium from the middle meatus, the velocity was significantly reduced to a local maximum of approximately 0.034 m/s inside the sinus. This by-pass flow rate through the sinus of 2.186×10(-1) to 3.591×10(-1) ml/s was a small fraction of the total flow rate inhaled from the nostril, but it effectively changed the local flow topology and led to a larger reduction in NO concentration in the maxillary sinus. This more rapid reduction in NO concentration was due to enhanced ventilation activity afforded by convective transport of the transit stream through the flow path connecting the natural ostium and the AO. The inspiration and expiration phases were qualitatively similar in flow pattern except for the flow direction in the maxillary sinus, suggesting that the AO plays a similar physiological role during both inspiration and expiration in terms of ventilation.  相似文献   
998.
In polyglutamine diseases, an abnormally elongated polyglutamine tract results in protein misfolding and accumulation of intracellular aggregates. The length of the polyglutamine expansion correlates with the tendency of the mutant protein to aggregate, as well as with neuronal toxicity and earlier disease onset. Although currently there is no effective cure to prevent or slow down the progression of these neurodegenerative disorders, increasing the clearance of mutant proteins has been proposed as a potential therapeutic approach. The ubiquitin-proteasome system and autophagy are the two main degradative pathways responsible for eliminating misfolded and unnecessary proteins in the cell. We will review some of the studies that have proposed autophagy as a strategy to reduce the accumulation of polyglutamine-expanded protein aggregates and protect against mutant protein neurotoxicity. We will also discuss some of the currently known mechanisms that induce autophagy, which may be beneficial for the treatment of these and other neurodegenerative disorders.  相似文献   
999.
目的: 研究ATP竞争性糖原合成酶激酶3(GSK-3)抑制剂6-溴靛玉红-3'-肟(BIO)作用于食管鳞癌细胞后, 对ATP结合盒(ABC)转运蛋白——P-糖蛋白(P-gp)和多药耐药相关蛋白2(MRP2)、凋亡抑制蛋白Bcl-2以及β-catenin表达的影响,探讨它们表达的相互关系,以及对细胞内游离ATP水平和P-gp、MRP2转运功能的影响,进而初步探讨GSK-3抑制剂对食管鳞癌细胞多药耐药的影响。方法: BIO作用于食管鳞癌EC-109细胞后,运用免疫荧光细胞化学法、流式细胞术以及ATP检测试剂盒分别检测细胞内 MRP2、P-gp、β-catenin和Bcl-2表达的改变、ABC转运蛋白的转运功能以及细胞内游离ATP水平的改变。结果: BIO作用食管鳞癌EC-109细胞后,加药组与对照组相比,β-catenin和Bcl-2在胞浆中的表达增强,并且β-catenin出现胞核内累积,MRP2在胞浆和胞膜中表达增强,P-gp在胞浆和胞膜中表达减弱;细胞内游离ATP水平增加;ABC转运蛋白的转运功能增强。结论: BIO处理食管鳞癌细胞后增强了细胞的多药耐药。  相似文献   
1000.
A better knowledge of the processes by which endothelium can resist to cell death and adapt to injury by specific intracellular signaling pathways and dedicated protein regulation is a key step to understand how vascular inflammation/injury develops and how it is regulated. This review focuses on signaling pathways and molecular effectors that trigger the balance between endothelial cell activation and dysfunction. In addition to the canonical nuclear factor-κB (NF-κB), phosphatidyl inositol 3-kinase (PI-3K) and mitogen-activated protein kinases (MAPK) that orchestrated the inflammatory response and its termination we report here additive pathways such as Notch pathway and protein C/protease activated receptor (PAR) pathway that have been also reported to play a role in the control of EC activation and apoptosis. This review also provides an update of the characteristics of some established and novel protective molecules for the endothelium, identified in transplantation.  相似文献   
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