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11.
不同粘结剂对瓷-牙本质粘结剪切强度的研究   总被引:1,自引:0,他引:1  
目的:观察比较不同树脂粘结剂对IPS Empress 2全瓷基底粘结剪切强度的效果。方法:选择无龋坏的人磨牙24个,随机分为4组,每组6个。第1组用RelyX Veneer进行粘结。第2组用RelyX unicem进行粘结。第3组用RelyX ARC进行粘结。第4组用Variolink 2进行粘结。所有样本在37°C蒸馏水中储存24h后,进行测试,记录剪切强度值,用SPSS11.0对结果进行单因素方差分析,并在光学显微镜下观察粘结破坏情况。结果:RelyX Veneer、RelyX ARC、Variolink 2的剪切强度显著高于RelyX unicem的剪切强度(P〈0.05),破坏界面多发生在牙本质与粘结剂之间。结论:RelyX Veneer、RelyX ARC、Variolink 2都可以用于IPS Empress 2全瓷系统的粘结。  相似文献   
12.
目的 分析破裂和未破裂腹主动脉瘤(AAA)曲率和血流动力学参数差异,探讨AAA破裂相关风险。方法 回顾性分析2019年10月至2020年12月在重庆医科大学附属第一医院确诊并接受治疗的35例AAA患者临床资料,其中瘤体破裂13例,未破裂22例。依据患者CTA影像资料,采用计算流体力学(CFD)方法分析比较两组患者解剖学因素和血流动力学参数间差异和相关性。结果 破裂组AAA破裂处壁剪切应力(WSS)显著小于最大血流冲击处WSS[0.025(0.049/0.018) Pa比0.549(0.839/0.492) Pa,P=0.01]。未破裂组瘤体最大血流冲击处WSS显著大于破裂组[(1.378±0.255) Pa比0.549(0.839/0.492) Pa,P<0.01]。破裂组与未破裂组瘤体最大直径[(79.847±10.067) mm比(52.320±14.682) mm,P<0.01]、曲率[(0.139±0.050)比0.080(0.123/0.068),P=0.021]差异均有统计学意义。瘤体最大直径与瘤颈直径呈负相关(r=-0.732,P<0.01),与曲率呈正...  相似文献   
13.
百令胶囊在肾移植术后早中期的应用研究   总被引:4,自引:1,他引:4  
为研究百令胶囊在肾移植术后早,中期的免疫抑制作用,将肾移植患者分为3组,A组为百令胶囊+Pred+CsA,B组为百令胶囊+Pred+CsA+AzaC组为Pred+CsA+Aza。结果:1.急性排斥发生情况:A组16.5%(33/200),B组11.79%(33/280),C组16%(16/100),2.肝功能损害情况;A组18.5%,B组为21.07%,C组25%,3.白细胞下降,A组无,B组12  相似文献   
14.
目的:观察治伤巴布剂对大鼠急性软组织损伤模型骨骼肌中AQP-1表达的影响.方法:SD大鼠54只,随机分成3组,分别为正常对照组、模型组和药物处理组.造模后1h、6h、1d、3d、5d、7d6个时相点处死动物,每组每个时相点3只,在标记的区域内肌肉组织取材,采用干湿比重法测定骨骼肌组织的含水量,应用Western Blot、qPCR法检测AQP-1蛋白及基因的表达水平,并进行相关分析.结果:检测的6个时相点中,模型组和药物处理组的肌肉组织含水量均高于正常对照组,在3d、5d、7d3个时相点,药物处理组的含水量低于模型组,药物处理组、模型组的AQP-1蛋白及基因表达水平均高于正常对照组,而药物处理组与模型组相比,差异具有统计学意义.结论:治伤巴布剂具有减轻急性软组织肿胀的作用,从而加速急性软组织损伤后修复的进程.  相似文献   
15.
3D printing (or more formally called additive manufacturing) has the potential to revolutionize the way objects are manufactured, ranging from critical applications such as aerospace components to medical devices, making the materials stronger, lighter and more durable than those manufactured via conventional methods. While the mechanical properties of Ti-6Al-4V parts manufactured with two major 3D printing techniques: selective laser melting (SLM) and electron beam melting (EBM), have been reported, it is unknown if the corrosion resistance of the 3D-printed parts is comparable to that of the alloy made with isothermal forging (ISF). The aim of this study was to identify the corrosion resistance and mechanisms of Ti-6Al-4V alloy manufactured by SLM, EBM and ISF via electrochemical corrosion tests in 3.5% NaCl solution, focusing on the effect of microstructures. It was observed that the equiaxed α + β microstructure in the ISF-manufactured Ti-6Al-4V alloy had a superior corrosion resistance to the acicular martensitic α′ + β and lamellar α + β microstructures of the 3D-printed samples via SLM and EBM, respectively. This was mainly due to the fact that (1) a higher amount of β phase was present in the ISF-manufactured sample, and (2) the fraction of phase interfaces was lower in the equiaxed α + β microstructure than in the acicular α′ + β and lamellar α + β microstructures, leading to fewer microgalvanic cells. The lower corrosion resistance of SLM-manufactured sample was also related to the higher strain energy and lower electrochemical potential induced by the presence of martensitic twins, resulting in faster anodic dissolution and higher corrosion rate.  相似文献   
16.
BackgroundRepeated transcatheter arterial chemoembolization (TACE) could cause ischemia of the tumor tissue and increases production of angiogenic factors in patients with hepatocellular carcinoma (HCC). Lenvatinib can inhibit the expression of angiogenic factors induced by ischemia after TACE and reduce angiogenesis and tumor recurrence. TACE-lenvatinib sequential therapy may improve clinical outcomes. There have been few investigations of TACE-lenvatinib sequential therapy for the treatment of unresectable HCC. We aimed to evaluate the efficacy and safety of TACE-lenvatinib sequential therapy for unresectable HCC.MethodsFrom May 2018 to May 2021, 53 consecutive patients who underwent TACE-lenvatinib sequential therapy were retrospectively reviewed. Of these, 30 patients who met the inclusion criteria were selected. Lenvatinib treatment started within 1 or 2 weeks after TACE at a dose of 8 or 12 mg once daily. Treatment response was assessed using dynamic magnetic resonance imaging (MRI) according to the modified response evaluation criteria in solid tumor (mRECIST). Blood tests were also performed at every response evaluation. Patients with complete response (CR) or partial response (PR) and stable disease (SD) received continuous lenvatinib therapy, and patients with progressive disease (PD) received repeated TACE. The progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and adverse events (AEs) were calculated. Statistical analysis was performed using the Kaplan-Meier method.ResultsThe median age was 58.5±9.1 years, and 16.7% (5/30) of patients were female. A total of 12 patients were categorized as Barcelona Clinic Liver Cancer (BCLC) Stage B and 18 were BCLC Stage C. The mean follow-up time was 15.7 months. The ORR was 76.7% (23/30), and the DCR was 96.7% (29/30). The median PFS was 6.1 months, and the median OS was 20.7 months. The most common lenvatinib-related AE was rash, and the most common TACE-related AE was elevated aspartate aminotransferase (AST). No treatment-related mortality was observed.ConclusionsFrom our findings, TACE-lenvatinib sequential therapy may prolong OS and PFS in patients with unresectable HCC, and the side effects are acceptable. The efficacy and safety of the sequential therapy should be confirmed in multiple center randomized controlled trials (RCTs) with a large sample and sufficient follow-up period.  相似文献   
17.
目的:观察声门癌及癌旁组织中SKP2及MRP-1/CD9蛋白的变化意义及其对声门癌手术安全切除范围的指导意义。方法:用免疫组织化学SP法检测38例声门鳞状细胞癌组织及距癌组织边缘2、5、10mm的组织中SKP2及MRP-1/CD9蛋白的表达,并取10例声带息肉组织作对照。结果:SKP2蛋白产物异常表达按息肉黏膜组织、癌旁组织(2、5、10mm)及癌组织的顺序依次递减,差异有统计学意义(均P<0.05);MRP-1/CD9蛋白产物异常表达按息肉黏膜组织、癌旁组织(2、5、10mm)及癌组织的顺序依次递增,差异有统计学意义(均P<0.05)。结论:SKP2及MRP-1/CD9均可作为判断喉癌生物学特性的参考指标,声门癌手术安全切缘以距肿瘤≥5mm的标准较为适宜。  相似文献   
18.
Immune checkpoint blockade(ICB) therapy has recently shown promise in treating several malignancies. However, only a limited number of patients respond to this treatment, partially because of the “immune cold” condition of the tumor immune microenvironment. Pyroptosis is a type of gasdermin-mediated programmed cell death that often leads to inflammation and immune responses. Many studies on the mechanism and function of pyroptosis have led to increasing recognition of the role of pyroptosis in m...  相似文献   
19.
为了研究小胶质细胞和血中炎症细胞对脑炎症的影响,在正常和白细胞减少大鼠的黑质致密部(SNpc)、皮层和海马注射脂多糖(LPS),用特异标记来研究中性粒细胞、小胶质细胞和单核细胞的行为学。CD11b+和Iba-1+阳性细胞在正常脑和LPS注射后6h反应相似。注射后12hIba-1+细胞消失而CD11b+变成圆形。CD11b/Iba-1双阳性网状小胶质细胞在LPS注射后6h死亡。注射后12h检测到的CD11b+细胞是MPO+细胞。这些CD11b+/MPO+细胞在白细胞减少的大鼠脑内不出现,提示中性粒细胞浸润。MPO+中性粒细胞表达一氧化氮合酶(iNOS)、IL-1β、环氧合酶-2(COX-2)和单核细胞趋化蛋白-1(MCP-1),但在注射后18h死亡。在24h检测到的CD11b+细胞是浸润的单核细胞,因为这些细胞曾经是Iba-1+而且在白细胞减少的大鼠脑内不出现。而且,在LPS注射的脑内可以检测到移植的单核细胞。这些结果提示,在发生炎症的脑内,至少有一部分中性粒细胞和单核细胞被认为是活化的小胶质细胞。  相似文献   
20.
Correction for ‘Preparation and characterization of a novel drug-loaded Bi-layer scaffold for cartilage regeneration’ by Yunqing Yue et al., RSC Adv., 2022, 12, 9524–9533, https://doi.org/10.1039/D2RA00311B.

The authors regret that part of Fig. 1 and the Graphical Abstract were reproduced from a published article without appropriate acknowledgment. The reference to be included is Girão et al., Compos. B. Eng., 2018, 154, 99–107, https://doi.org/10.1016/j.compositesb.2018.08.001.Girão et al. have granted permission for part of their Fig. 1 to be used in “Preparation and characterization of a novel drug-loaded Bi-layer scaffold for cartilage regeneration”.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
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