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   51831篇
  免费   4566篇
  国内免费   1810篇
耳鼻咽喉   462篇
儿科学   860篇
妇产科学   484篇
基础医学   7938篇
口腔科学   3154篇
临床医学   5611篇
内科学   5052篇
皮肤病学   6157篇
神经病学   1981篇
特种医学   2133篇
外国民族医学   11篇
外科学   7423篇
综合类   6279篇
现状与发展   10篇
预防医学   1554篇
眼科学   636篇
药学   3827篇
  20篇
中国医学   1669篇
肿瘤学   2946篇
  2023年   939篇
  2022年   878篇
  2021年   1618篇
  2020年   1999篇
  2019年   1844篇
  2018年   1814篇
  2017年   1724篇
  2016年   1831篇
  2015年   1826篇
  2014年   3125篇
  2013年   4481篇
  2012年   2720篇
  2011年   3176篇
  2010年   2482篇
  2009年   2510篇
  2008年   2567篇
  2007年   2682篇
  2006年   2383篇
  2005年   2181篇
  2004年   1906篇
  2003年   1696篇
  2002年   1340篇
  2001年   1232篇
  2000年   872篇
  1999年   871篇
  1998年   648篇
  1997年   636篇
  1996年   568篇
  1995年   565篇
  1994年   484篇
  1993年   390篇
  1992年   425篇
  1991年   374篇
  1990年   330篇
  1989年   310篇
  1988年   297篇
  1987年   277篇
  1986年   242篇
  1985年   284篇
  1984年   232篇
  1983年   169篇
  1982年   202篇
  1981年   208篇
  1980年   182篇
  1979年   142篇
  1978年   96篇
  1977年   82篇
  1976年   108篇
  1975年   51篇
  1972年   41篇
排序方式: 共有10000条查询结果,搜索用时 173 毫秒
31.
本文报告1例因牙齿根面畸形导致严重根尖病变及牙周破坏的牙周牙髓联合病变的左上侧切牙,瘘道长期不愈,腭侧窄而深牙周袋,严重根尖病变及牙槽骨垂直吸收。通过显微根管治疗、根尖手术、引导牙周组织再生术治疗,实现了控制根尖及牙周感染,达到了保留患牙的目的。  相似文献   
32.
33.
Depigmented patches in vitiligo, a common dermatosis, cause a great psychological distress to the patients. Hence, apart from halting the disease process, the strategies to impart normal skin colour to these white patches carry an important role in the management of vitiligo. Surgical procedures are often required for stable vitiligo lesions not responding to medical therapies. It involves “shuffling” of melanocytes from the pigmented skin to the depigmented areas. During the last fifty years, the vitiligo surgery has evolved from tissue transplantation via cellular transplantation to reach a stage where the use of stem cells or immunomodulatory cells is contemplating. We would like to depict this wonderful journey of vitiligo surgery through this viewpoint.  相似文献   
34.
35.
Phaeohyphomycosis is a chronic subcutaneous fungal infection caused by dematiaceous fungi, commonly involving the extremities, which present as single or multiple lesions mimicking a benign tumor. Fine‐needle aspiration cytology (FNAC) is an easy method for the diagnosis of the lesion. Morphology of the fungus is characteristic with no difficulty for cytopathologist for identification; with a close differential diagnosis of Candida and Aspergillosis. The special stains like periodic acid schiff (PAS) highlights the fungus and the Masson Fontana confirm the melanin pigment and dematiaceous nature of the fungi. Liquid‐based cytology (LBC) preparation of the aspirated material was attempted, which is not usually performed on day to day basis. However, in our case the conventional smears were better for appreciating the fungal morphology.  相似文献   
36.
Free microsurgical tissue transfer of the latissimus dorsi flap may be indicated for the restoration of intra- and extraoral defects, especially when a large-sized skin island flap is required. In many cases, use of the latissimus dorsi flap for coverage of large-sized intraoral defects results in bulkiness due to the proportion of subcutaneous fat. Prelamination of free flaps appears to be a promising technique to overcome this flap bulkiness. This modification in flap design could improve the postoperative functional outcome, as well as reduce donor site morbidity. This article presents four novel clinical cases, in which the patients underwent prelamination of the latissimus dorsi flap with local skin grafts during oral cancer treatment in order to reduce the thickness of the free flap and allow tension-free primary closure of the donor site. These attempts successfully covered large-sized intraoral defects, achieving good functional outcomes with minimal donor site morbidity.  相似文献   
37.
38.
39.
段海珊  蒋黎  刘慧敏  朱研  郭建琼 《西部医学》2019,31(11):1757-1761
【摘要】 目的 探讨实时超声弹性成像在诊断慢性乙肝肝纤维化程度中的应用价值。方法 以2016年1月~2019年1月我院收治的慢性乙型肝炎(CHB)患者146例为研究对象。分别行肝脏穿刺检查及实时组织弹性成像(RTE)检查,然后进行病理分期,并记录相应的应变均值(MEAN)、标准偏差(SD)、蓝色区域面积比(%AREA)、复杂度(COMP)、峰度(KURT)、偏度(SKEW)、对比度(CONT)、均等性(ENT)、杂乱度(IDM)、一致性(ASM)、相关性(CORR),并计算得出肝纤维化指数(LFI)值。结果 与S0、S1、S2期比较,S4期MEAN显著降低(P<0.05);与S0、S1、S2、S3期比较,S4期%AREA、COMP显著升高(P<0.05);与S0、S1、S2期比较,S4期SKEW、LFI显著升高(P<0.05);与S0期比较,S3期LFI显著升高(P<0.05)。Spearman相关分析结果示,MEAN、ENT与肝纤维化分期呈负相关(P<0.05)。SD、%AREA、COMP、SKEW、IDM、ASM、LFI与肝纤维化分期呈正相关(P<0.05)。RTE参数MEAN、%AREA、COMP、SKEW、IDM、LFI诊断肝纤维化程度的ROC曲线下面积均在0.7~0.9。当MEAN、%AREA、COMP、SKEW、IDM、LFI 6个参数的截断值分别取10029、3014、2752、042、012、281时,诊断肝纤维化程度的准确性和特异性均在70%以上。〖HT5"H〗结论〖HTK〗〓实时组织弹性成像与慢性乙型肝炎肝纤维化分期具有较高的相关性,其中与肝纤维化指数的相关系数最大,其在慢性乙型肝炎肝纤维化的诊断和评估中具有重要应用价值。  相似文献   
40.
Three-dimensional surgical planning is used widely in orthognathic surgery. Although numerous computer programs exist, the accuracy of soft tissue prediction remains uncertain. The purpose of this study was to compare the prediction accuracy of Dolphin, ProPlan CMF, and a probabilistic finite element method (PFEM). Seven patients (mean age 18 years; five female) who had undergone Le Fort I osteotomy with preoperative and 1-year postoperative cone beam computed tomography (CBCT) were included. The three programs were used for soft tissue prediction using planned and postoperative maxillary position, and these were compared to postoperative CBCT. Accurate predictions were obtained with each program, indicated by root mean square distances: RMSDolphin = 1.8 ± 0.8 mm, RMSProPlan = 1.2 ± 0.4 mm, and RMSPFEM = 1.3 ± 0.4 mm. Dolphin utilizes a landmark-based algorithm allowing for patient-specific bone-to-soft tissue ratios, which works well for cephalometric radiographs but has limited three-dimensional accuracy, whilst ProPlan and PFEM provide better three-dimensional predictions with continuous displacements. Patient or population-specific material properties can be defined in PFEM, while no soft tissue parameters are adjustable in ProPlan. Important clinical considerations are the topological differences between predictions due to the three algorithms, the non-negligible influence of the mismatch between planned and postoperative maxillary position, and the learning curve associated with sophisticated programs like PFEM.  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