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   75805篇
  免费   4407篇
  国内免费   1592篇
耳鼻咽喉   661篇
儿科学   914篇
妇产科学   1009篇
基础医学   6832篇
口腔科学   4096篇
临床医学   5960篇
内科学   4990篇
皮肤病学   245篇
神经病学   2107篇
特种医学   4527篇
外国民族医学   3篇
外科学   25746篇
综合类   11179篇
现状与发展   1篇
预防医学   2876篇
眼科学   464篇
药学   5423篇
  71篇
中国医学   2461篇
肿瘤学   2239篇
  2024年   129篇
  2023年   813篇
  2022年   1814篇
  2021年   2470篇
  2020年   2301篇
  2019年   1827篇
  2018年   1945篇
  2017年   2010篇
  2016年   2487篇
  2015年   2491篇
  2014年   4888篇
  2013年   4956篇
  2012年   4481篇
  2011年   5067篇
  2010年   4319篇
  2009年   4329篇
  2008年   4031篇
  2007年   4091篇
  2006年   3712篇
  2005年   3506篇
  2004年   2896篇
  2003年   2422篇
  2002年   1857篇
  2001年   1631篇
  2000年   1497篇
  1999年   1307篇
  1998年   1095篇
  1997年   993篇
  1996年   790篇
  1995年   759篇
  1994年   640篇
  1993年   550篇
  1992年   444篇
  1991年   386篇
  1990年   304篇
  1989年   278篇
  1988年   268篇
  1987年   227篇
  1986年   234篇
  1985年   216篇
  1984年   172篇
  1983年   110篇
  1982年   160篇
  1981年   143篇
  1980年   124篇
  1979年   131篇
  1978年   109篇
  1977年   92篇
  1976年   67篇
  1973年   43篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
目的:探讨轴向载荷分担比用于胫腓骨骨干骨折术后指导外固定器轴向动力化促进骨折愈合的有效性。方法:选取外固定器治疗的胫腓骨骨干骨折患者100例,随机分为观察组50例,对照组50例。观察组在轴向载荷分担比指导下行外固定器轴向动力化治疗,对照组未行动力化,随访比较两组的治疗效果。结果:所有患者均获随访,随访时间4~12个月,平均6.5个月,治疗期间所有患者均未出现外固定针断裂、松动及再骨折等并发症,观察组1例骨搬移患者轴向载荷分担比5%,X线片显示骨折断端有连续性骨痂通过,拆除外固定器连接杆后发生移位,恢复原数值行轴向加压再动力化,现已愈合。观察组除外1例骨搬移患者,其余49例患者外固定器固定时间为[(24.4±4.7)周],骨折临床愈合时间为[(22.4±4.7)周],与对照组50例患者外固定器固定时间[(29.3±5.6)周],骨折临床愈合时间[(27.3±5.6)周]比较,显著减少(P0.05)。结论:外固定器轴向载荷分担比指导胫腓骨骨干骨折外固定术后轴向动力化可以加速骨折愈合,但不适合骨搬移截骨端已硬化患者。  相似文献   
43.
目的探讨不同剂量骨水泥PKP联合雌激素对绝经后女性骨质疏松性腰椎体压缩性骨折患者的影响。方法选取2015年1月至2018年6月我院收治的120例老年女性骨质疏松性腰椎体压缩性骨折患者为研究对象,按行PKP手术治疗时骨水泥注入的剂量不同分为三组(A组2-4 mL、B组4-5 mL、C组5-6 mL),所有患者均随访1年,比较术后三组患者VAS评分、ODI评分、伤椎椎体前缘高度、椎体中部高度及并发症的发生率。结果三组患者相比,治疗前VAS评分、ODI评分组间比较差异无显著性(P0.05);术后3天及1年后随访时,三组患者各项指标均较治疗前显著改善,组内比较差异具有显著性(P0.05),组间比较差异无显著性(P0.05);治疗前伤椎椎体前缘高度及椎体中部高度组间比较差异无显著性(P0.05);术后3天及1年后随访时,三组患者治疗后椎体前缘、中间高度均较术前明显增加(P0.05),组间比较椎体前缘高度:C组B组A组,椎体中间高度:C组B组A组,且组间比较有统计学差异(P0.05); A组患者并发症的发生率(12.5%)明显低于B组(30.0%)、C组(41.0%),有统计学差异(P0.05)。结论 PKP术中注入小剂量骨水泥(2-4 mL)对于治疗老年女性OVCFs具有良好的治疗效果及较高的安全性。  相似文献   
44.
In normal tissue repair, macrophages exhibit a pro-inflammatory phenotype (M1) at early stages and a pro-healing phenotype (M2) at later stages. We have previously shown that M1 macrophages initiate angiogenesis while M2 macrophages promote vessel maturation. Therefore, we reasoned that scaffolds that promote sequential M1 and M2 polarization of infiltrating macrophages should result in enhanced angiogenesis and healing. To this end, we first analyzed the in vitro kinetics of macrophage phenotype switch using flow cytometry, gene expression, and cytokine secretion analysis. Then, we designed scaffolds for bone regeneration based on modifications of decellularized bone for a short release of interferon-gamma (IFNg) to promote the M1 phenotype, followed by a more sustained release of interleukin-4 (IL4) to promote the M2 phenotype. To achieve this sequential release profile, IFNg was physically adsorbed onto the scaffolds, while IL4 was attached via biotin-streptavidin binding. Interestingly, despite the strong interactions between biotin and streptavidin, release studies showed that biotinylated IL4 was released over 6 days. These scaffolds promoted sequential M1 and M2 polarization of primary human macrophages as measured by gene expression of ten M1 and M2 markers and secretion of four cytokines, although the overlapping phases of IFNg and IL4 release tempered polarization to some extent. Murine subcutaneous implantation model showed increased vascularization in scaffolds releasing IFNg compared to controls. This study demonstrates that scaffolds for tissue engineering can be designed to harness the angiogenic behavior of host macrophages towards scaffold vascularization.  相似文献   
45.
Myelofibrosis (MF) is a BCR-ABL1 myeloproliferative neoplasm that arises from hematopoietic stem and progenitor cells frequently harboring a somatic driver mutation in 1 of 3 genes: JAK2, CALR, or MPL. The pathologic features of this hematologic malignancy include myeloproliferation, diffuse bone marrow fibrosis, and overactivation of the JAK-STAT pathway, resulting in enhanced inflammatory cytokine release. The common clinical manifestations of MF include systemic symptoms, abnormal peripheral blood count levels, and splenomegaly. However, it has become increasingly appreciated that significant clinical heterogeneity exists among patients with MF. Two distinct MF clinical phenotypes include the myeloproliferative and myelodepletive phenotype, with peripheral blood counts being the main discerning feature. Patients with the myeloproliferative phenotype will present with elevated peripheral blood counts and often experience significant constitutional symptoms and progressive splenomegaly. In contrast, patients with the myelodepletive phenotype will have low peripheral blood counts and will frequently require transfusion support. Current frontline therapies for MF, include ruxolitinib and fedratinib, which can exacerbate cytopenias and thereby pose an impediment to effective treatment of the myelodepletive patient. The present review discusses the clinical and prognostic implications of the myelodepletive phenotype and the therapeutic options and limitations for this subset of patients, representing an unmet clinical need.  相似文献   
46.
47.
48.
Different methods have been used throughout the years for syndesmotic injury but there is no consensus on the ideal treatment. Some methods are expensive and some have more complications. The aim of this study is to compare single suture endobutton with double suture endobutton and screw fixation for syndesmotic injury.Sixty nine patients with syndesmotic injury with fibular fractures whom were treated with a single interosseous suture endobutton system (ZipTightTM, Zimmer Biomet), a double interosseous suture endobutton system (ZipTightTM, Zimmer Biomet) and 1 syndesmotic screw (TST, Istanbul, Turkey) were included in this study. Functional and radiological results from patient records between 2015 and 2018 were retrospectively evaluated.Twenty patients were treated with the double interosseous suture endobutton, 23 were treated with the single interosseous suture endobutton, and 26 were treated with traditional AO screw fixation. Three patients from the screw fixation group (11.5%) required revision surgery (P < .05). All the radiologic and clinical outcomes were statistical similar in all 3 groups.Our findings showed that the interosseous suture endobutton system is at least as safe as the screw fixation technique for treatment of syndesmosis joint injuries and can be used as an alternative to the screw method. The interosseous suture endobutton system eliminates the need for a second surgery to remove the hardware, which minimizes the probability of re-diastasis. Since our results showed no statistical difference between single and double interosseous suture endobutton systems, the less costly single endobutton system may be the better alternative.  相似文献   
49.
50.
目的:探讨可调式外固定支具治疗第5掌骨颈骨折的可行性及有效性。方法:选取2014年1月~2017年6月我院收治的54例第5掌骨颈骨折患者作为研究对象,随机分为A组和B组,每组27例。A组行闭合复位交叉克氏针固定,B组行手法整复可调式外固定支具固定,比较两组末次随访第5掌指关节活动度和主观满意度。结果:随访4~10个月,两组患者第5掌指关节活动度(ROM)值相比较,差异无统计学意义,P0.05;两组的主观满意度相比较,差异无统计学意义,P0.05。结论:手法整复可调式外固定支具固定可为第5掌骨颈骨折提供可靠、有效的固定,有助于患者的早期功能恢复,是一种有效的治疗方法。  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