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1.
目的 探讨慢性乙型肝炎(CHB)患者肝X受体α(LXRα)和细胞色素P450亚型7A1(CYP7A1)基因表达水平与肝组织病理学炎症和纤维化程度的关系。方法 2019年1月~2020年10月我院收治的CHB患者118例,均接受肝穿刺活检,将炎症活动度分级>G2和肝纤维化分期>S2定义为肝组织炎症或纤维化程度显著;采用免疫组织化学染色法检测肝组织LXRα和CYP7A1表达,采用RT-PCR法检测LXRα mRNA和CYP7A1 mRNA水平。结果 118例CHB患者肝组织LXRα和CYP7A1蛋白和/或其mRNA阳性分别为78.0%和73.7%;38例肝组织显著炎症组LXRα mRNA和其蛋白(AOD)水平分别为(0.6±0.2)和(0.3±0.1),显著高于80例非显著炎症患者[分别为(0.4±0.1)和(0.1±0.0),P<0.05],CYP7A1 mRNA和其蛋白(AOD)水平分别为(0.8±0.2)和(0.4±0.1),显著高于非显著炎症患者[分别为(0.3±0.1)和(0.1±0.0),P<0.05];48例显著肝纤维化组肝组织LXRα mRNA和其蛋白(AOD)水平分别为(0.7±0.2)和(0.3±0.1),显著高于70例非显著肝纤维化患者[分别为(0.3±0.1)和(0.1±0.1),P<0.05],CYP7A1 mRNA和其蛋白(AOD)水平分别为(0.7±0.2)和(0.3±0.1),显著高于非显著肝纤维化患者[分别为(0.4±0.2)和(0.2±0.1),P<0.05]。结论 LXRα和CYP7A1表达上调可能参与了CHB患者肝组织炎症和肝纤维化发生发展过程,其机制值得进一步研究。  相似文献   
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In the present study, we evaluated the antitumor, anti-tyrosinase, anti-pancreatic lipase, antibacterial, antifungal, and anti-α‐glycosidase activities for all or a subset of 20 known compounds. They included 8 phenyl benzoates, 10 benzophenones, and 2 xanthones. Phenyl benzoate compounds 1–8 did not exhibit evident antitumor activity, which was consistent with existing theories. Compounds 16, 17, and 18 exhibited moderate anti-tyrosinase activity. In addition, compounds 11 and 18 exhibited moderate inhibitory activity against Candida albicans, and compound 20 exhibited stronger anti-α-glycosidase activity than quercetin, with an IC50 of approximately 2.45 μM. These results demonstrated that compounds 11, 16–18, and 20 were promising leads for further structural modification.  相似文献   
3.
《Acta histochemica》2022,124(8):151955
BackgroundAngiogenesis is an essential physiological process in the growth and metastasis of primary tumors. Ca2+ signaling is crucial for tumor angiogenesis. The purpose of this study was to detect the potential role of Ca2+ permeable transient receptor potential vanilloid-3 (TRPV3) in the angiogenesis of non-small cell lung cancer (NSCLC).MethodsSmall interfering RNA was used to down-regulate TRPV3 expression in A549 cells. A laser scanning confocal microscope was used to examine intracellular calcium concentration ([Ca2+]i). Human umbilical vein endothelial cells (HUVECs) tube formation and migration assay, Western blot, MTT and ELISA were performed to detect the potential mechanisms of TRPV3 in tumor angiogenesis. A mouse tumor xenograft model was performed to expound the effects of TRPV3 on tumor cell growth.ResultsInhibition of TRPV3 reduced [Ca2+]i and protein expressions of VEGF and HIF-1α in A549 cells. Moreover, HIF-1α depletion decreased the secretion and expression of VEGF. Depletion of TRPV3 inhibited HUVECs proliferation, tube formation and migration induced by conditioned medium. And TRPV3 inhibition could decrease the volume of xenograft tumors and MVD of CD34+ cells. The expression levels of HIF-1α, VEGF and p-CaMKП in the xenograft tumors in RuR and siTRPV3 groups was reduced.ConclusionsTRPV3 calcium channel protein may play a key role in NSCLC angiogenesis. TRPV3 could promote the angiogenesis through HIF-1α-VEGF signaling pathway. Targeting TRPV3 channel protein by novel approaches would be useful for reversing NSCLC angiogenesis.  相似文献   
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《Dental materials》2022,38(2):397-408
ObjectivesComposite restorations with calcium fluoride nanoparticles (nCaF2) can remineralize tooth structure through F and Ca ion release. However, the persistence of ion release is limited. The objectives for this study were to achieve long-term remineralization by developing a rechargeable nCaF2 nanocomposite and investigating the F and Ca recharge and re-release capabilities.MethodsThree nCaF2 nanocomposites were formulated: (1) BT-nCaF2:Bisphenol A glycidyl dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA); (2) PE-nCaF2:Pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA); (3) BTM-nCaF2:BisGMA, TEGDMA, and Bis[2-(methacryloyloxy)ethyl] phosphate (Bis-MEP). All formulations contained 15% nCaF2 and 55% glass particles. Initial flexural strength and elastic modulus, F and Ca ion release, recharge and re-release were tested and compared to three commercial fluoride-containing materials.ResultsBT and BTM nCaF2 composites were 3–4 times stronger and had elastic modulus 2 times that of resin-modified glass ionomer controls. PE-nCaF2 had comparable strength to RMGIs. All nCaF2 composites had significant F and Ca ion release and ion rechargeability. In F and Ca recharging cycles, PE-nCaF2 had the highest ion recharging capability among nCaF2 groups, followed by BT-nCaF2 and BTM-nCaF2 (p < 0.05). For all recharge cycles, ion release maintained similar levels, demonstrating long-term ion release was possible. Furthermore, after the final recharge cycle, nCaF2 nanocomposites provided continuous ion release for 42 days without further recharge.SignificanceNovel nCaF2 rechargeable nanocomposites exhibited significant F and Ca ion release over multiple recharge cycles, demonstrating continuous long-term ion release. These nanocomposites are promising restorations with lasting remineralization potential.  相似文献   
7.
目的探讨白介素-6(interleukin-6,IL-6)对糖尿病周围神经病变大鼠的干预性作用及可能的机制。方法选取2015年10月至2018年12月80只健康雄性wistar大鼠作为研究对象,随机分为对照组、糖尿病非干预组、糖尿病低剂量IL-6干预组(1μg/kg,每周3次,皮下注射)和糖尿病高剂量IL-6干预组(10μg/kg,每周3次,皮下注射),每组20只。糖尿病大鼠造模应用尾静脉注射链脲菌素45 mg/kg方法,随机血糖>16.7 mmol/L为造模成功。检测各组大鼠外周血IL-6、腓肠神经形态学改变,以及腓肠神经NF-κB、I?Bα、IL-6mRNA及蛋白表达。结果糖尿病大鼠的糖化血红蛋白、血IL-6水平、腓肠神经IL-6、NF-κB、I?Bα表达水平均高于对照组,差异有统计学意义(P<0.05)。腓肠神经病理可见纤维密度减少,截面积减小,呈萎缩趋势,可见少量异常有髓纤维。应用IL-6干预后大鼠的腓肠神经病理改变较非干预组明显改善,且IL-6,NF-κB,I?Bα的mRNA及蛋白表达水平低于非干预组,高剂量IL-6干预后上述炎症因子的表达与非干预组比较差异有统计学意义(P<0.05)。结论 IL-6可通过抑制腓肠神经NF-κB的表达,缓解糖尿病大鼠周围神经病变的进展。  相似文献   
8.
目的研究急性支气管哮喘(BA)经特步他林并布地奈德治疗后白介素-5(IL-5)、白介素-10(IL-10)、肿瘤坏死因子-α(TNF-α)的变化。方法选取2016年1月至2020年12月商丘市中医院收治的122例急性BA患者的临床资料进行分析,根据不同治疗方法分为研究组(n=62,特步他林+布地奈德)和对照组(n=60,特步他林),比较两组临床疗效、肺功能[用力肺活量(FVC)、1秒用力呼气容器(FEV1)、1秒用力呼气容积占用力肺活量的百分比(FEV1/FVC%)、治疗前后IL-5、IL-10、TNF-α变化及不良反应情况。结果研究组总疗效(93.55%)高于对照组(81.67%),差异有统计学意义(P<0.05)。治疗后两组FVC、FEV1、FEV1/FVC%均较治疗前升高,且研究组高于对照组,差异具有统计学意义(P<0.05)。治疗后两组IL-5、TNF-α水平均降低,且研究组低于对照组,两组IL-10水平均上升,且研究组高于对照组,差异有统计学意义(P<0.05)。两组不良反应率比较差异无统计学意义(P>0.05)。结论特步他林与布地奈德联合治疗急性BA的效果显著,能够有效缓解患者的气道炎症反应,促进其肺功能的恢复,且联合用药无不良反应增加。  相似文献   
9.
PurposeTo investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model.Materials and MethodsVX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry.ResultsThe median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 μg/mL (interquartile range [IQR], 7.42–33.5 μg/mL), and its maximal plasma concentration (Cmax) was 0.164 μg/mL (IQR, 0.0798–0.528 μg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 μg/mL (IQR, 3.18–4.79 μg/mL) and 0.677 μg/mL (IQR, 0.315–1.23 μg/mL), respectively, in the DOX-TACE group and 1.68 μg/mL (IQR, 0.795–4.08 μg/mL) and 0.298 μg/mL (IQR, 0.241–0.64 μg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups.ConclusionsThe addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin.  相似文献   
10.
目的:观察干扰素α(interferon-α,IFN-α)联合亚砷酸治疗JAK2V617F突变阳性的真性红细胞增多症(polycythemia vera,PV)和原发性血小板增多症(essential thrombocythemia,ET)患者的有效性及安全性。方法:回顾性分析2015年12月至2021年01月在我院血液科收治的44例PV和ET患者的临床资料,比较IFN-α联合亚砷酸(观察组)以及单用IFN-α(对照组)的疗效及不良反应。结果:观察组血液学总有效率(overall response rate,ORR)为88.5%,高于对照组。至随访截止时,观察组达血液学及分子生物学缓解的ORR均高于对照组。并且观察组并未出现不良反应发生率增加的情况。结论:亚砷酸能加速并增强IFN-α抗肿瘤作用,二者联合治疗能提高JAK2V617F突变阳性的PV和ET的临床缓解率和疗效持续时间,且安全性高。  相似文献   
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