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   128809篇
  免费   12163篇
  国内免费   5660篇
耳鼻咽喉   1141篇
儿科学   1265篇
妇产科学   1753篇
基础医学   13696篇
口腔科学   3097篇
临床医学   15477篇
内科学   11388篇
皮肤病学   1313篇
神经病学   4324篇
特种医学   4169篇
外国民族医学   58篇
外科学   12628篇
综合类   27758篇
现状与发展   25篇
一般理论   5篇
预防医学   12855篇
眼科学   3952篇
药学   12517篇
  99篇
中国医学   11078篇
肿瘤学   8034篇
  2024年   142篇
  2023年   2147篇
  2022年   3974篇
  2021年   5118篇
  2020年   5186篇
  2019年   3046篇
  2018年   3185篇
  2017年   2810篇
  2016年   3233篇
  2015年   4277篇
  2014年   10088篇
  2013年   9544篇
  2012年   14073篇
  2011年   13746篇
  2010年   10095篇
  2009年   8317篇
  2008年   6216篇
  2007年   7671篇
  2006年   6356篇
  2005年   4476篇
  2004年   4473篇
  2003年   4323篇
  2002年   3623篇
  2001年   2608篇
  2000年   2006篇
  1999年   1710篇
  1998年   1072篇
  1997年   948篇
  1996年   626篇
  1995年   269篇
  1994年   216篇
  1993年   202篇
  1992年   249篇
  1991年   186篇
  1990年   187篇
  1989年   88篇
  1988年   62篇
  1987年   40篇
  1986年   22篇
  1985年   15篇
  1984年   3篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
排序方式: 共有10000条查询结果,搜索用时 727 毫秒
1.
2.
This meta-analysis was designed to assess the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for patients with low back pain (LBP). Pubmed, Embase, Cochrane's library, PEDro (Physiotherapy Evidence Database), China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched until December 2019 to identify studies assessing the effectiveness and safety of EPSW for LBP. The prime outcome is pain intensity measured by Visual Analog Scale (VAS) or numeric rating scale (NRS). Other outcomes included functional status, quality of life, psychological outcomes measured by Oswestry Disability Index (ODI), as well as the adverse events. Mean differences (MD) were calculated for continuous outcomes, while odd ratios (OR) were calculated for binary outcomes. Revman 5.3 software was used for statistical analysis. Five randomized controlled trials (RCTs) were finally included in this meta-analysis. The pooled mean difference in post-treatment pain scores was −2.37 (P <0.0001), indicating that post-treatment pain scores was significantly higher by 2.37 in control group than in ESWT group. At a mean follow-up time of 4–6 weeks, the pooled mean difference in ODI scores was −14.10 (P <0.00001), indicating that the pooled mean difference of post-treatment ODI scores was 14.10 higher in control group than in ESWT group. The use of ESWT is effective in alleviating pain and improving the general functional state for patients with LBP. However, more evidence was needed to verify its safety.  相似文献   
3.
BackgroundAlthough there are many treatments for laryngeal contact granuloma (LCG), some patients still fail treatment. Botulinum toxin A injection vocal cords may be a salvage therapy.ObjectivesTo study the efficacy of thyroarytenoid botulinum toxin A injection for the treatment of refractory LCG.Material and methodsFrom May 2021 to March 2022, 23 male patients with refractory idiopathic LCG were treated by injection of botulinum toxin A into the thyroarytenoid muscle via the thyrohyoid membrane approach. Inspiratory-phase laryngoscopy images were collected before treatment and 3 months after injection treatment. The lesion size was evaluated with the Farwell granuloma endoscopic grading system and Image J software.ResultsThe average age of 23 patients was 49 years. The dose of botulinum toxin injection ranged from 2.5 to 5 units. Three months after injection, 17 patients were cured, 2 patients showed marked improvement, and 4 patients did not experience any effect. The total efficacy rate was 82.61% (19/23), and no serious complications occurred. Almost all patients experienced hoarseness within one week after injection; they gradually recovered after one month, and their voice returned to baseline at 3 months.ConclusionsThyroarytenoid botulinum toxin injection is an effective method for resolving refractory LCG.  相似文献   
4.
目的 鉴定与丹参酮合成相关转录因子AP2/ERF家族中SmERF108转录因子,并分析转录因子SmERF108的靶基因。方法 利用生物信息学在线分析平台如NCBI、PFAM等分析SmERF108的序列特征;MEGA-X软件用于构建SmERF108与不同功能转录因子的系统进化树;拟南芥原生质体转化法鉴定SmERF108蛋白的亚细胞定位;通过实时荧光定量PCR(Real-time qPCR)对SmERF108基因在丹参不同器官和组织差异表达进行检测;利用酵母体系对SmERF108的转录激活活性进行探究并用酵母单杂技术确定其靶基因。结果 SmERF108具有典型的AP2/ERF保守结构域,属于ERF-B3亚组,系统进化树和保守基序分析显示SmERF108与丹参中SmERF128、青蒿中AaERF2亲缘关系较近且保守基序分布一致;亚细胞定位显示SmERF108蛋白定位于细胞核;SmERF108基因在周皮中表达最高,且呈现周皮(R1)>韧皮部(R2)>木质部(R3)的规律;酵母自激活验证SmERF108具有转录激活活性,同时酵母单杂交确认其能与关键酶基因SmCPS1启动子结合。结论 鉴定到丹参中一个新转录因子SmERF108,生物信息学分析及差异表达分析预测与丹参酮合成相关,分子互作初步证实靶基因为SmCPS1二萜环化酶。  相似文献   
5.
《Cancer cell》2022,40(2):153-167.e11
  1. Download : Download high-res image (229KB)
  2. Download : Download full-size image
  相似文献   
6.
目的 探究高密度多孔聚乙烯植入体在鼻整形中的应用价值方法 选取2019年5月-2021年8月我院接受综合鼻整形手术的106例患者为研究对象,采用照随机数字表法分为对照组和观察组,各53例。 对照组采用自体肋骨植入术,观察组采用高密度多孔聚乙烯植入体植入治疗,比较两组临床手术指标(手术时间、恢复时间)、整形优良率、鼻指标(鼻高度/鼻长度比例、鼻唇角)、并发症发生率以及疼痛评分结果 观察组手术时间、术后恢复时间均短于对照组(P<0.05);观察组整形优良率为94.34%,高于对照组的86.79%,差异有统计学意义(P<0.05);观察组鼻高度/鼻长度比例高于对照组,鼻唇角小于对照组,差异有统计学意义(P<0.05);观察组并发症发生率为5.66%,低于对照组的15.09%,差异有统计学意义(P<0.05);观察组疼痛评分低于对照组,差异有统计学意义(P<0.05);观察组治疗满意度为 96.23%,高于对照组的84.91%,差异有统计学意义(P<0.05)结论 高密度多孔聚乙烯植入体在鼻整形中的应用效果理想,可减轻患者疼痛度,缩短手术和恢复时间,降低并发症发生率,改善鼻高度/鼻长度比例和鼻唇角,实现理想的整形效果。  相似文献   
7.
Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
8.
ObjectiveThe purpose of this study was to determine the accuracy and intrarater reliability of a palpatory protocol based on a combination of 3 palpatory methods to identify both the C7 spinous process (C7 SP) and the factors that affect the errors and inaccuracy of palpation.MethodsTwenty-five women between the ages of 18 and 60 years were submitted to a palpation protocol of the C7 SP, and a radiopaque marker was fixed on the skin at the possible location of the vertebrae. A radiograph and a photograph of the cervical spine were obtained in the same posture by a first rater. A second rater performed the same palpation protocol and took a second photograph. The accuracy and measurement error of the palpation protocol of C7 SP were assessed through radiographic images. The inter-rater reliability was estimated by the interclass correlation coefficient and assessed using photographs of each rater. The Pearson's correlation coefficients (r), the Fisher exact test, and the χ2 test were used to identify the factors associated with the error and inaccuracy of palpation.ResultsAccuracy of the C7 palpation was 76% with excellent reliability (interclass correlation coefficient = 0.99). There was a moderate correlation between weight and the measurement of palpation error (r = –0.6; P = .003). One hundred percent of inaccuracy palpation was related to the increased soft-tissue thickness (P = .005) in the cervical region.ConclusionThe palpation protocol described in this study was accurate and presented excellent reliability in identifying the C7 SP. Increased weight and dorsocervical fat pad were associated to error and palpation inaccuracy, respectively.  相似文献   
9.
目的分析细棒、PEEK棒固定对寰枢关节稳定性的影响。方法采用6具新鲜成人枕骨(occipital bone,Oc)~颈椎C4节段进行测试,模拟以下手术及固定状态:①完整状态;②损伤状态:枢椎齿状突II型骨折;③坚强固定:寰枢椎均采用普通椎弓根螺钉固定,直径3.5 mm钛棒连接;④PEEK棒:直径3.5 mm的PEEK棒连接;⑤细棒:直径2.0 mm钛棒连接。采用重复测量实验设计,在完整、损伤和不同的固定状态下,通过脊柱试验机对标本分别施加1.5 N·m的前屈/后伸、左/右侧弯和左/右轴向旋转的纯力偶矩。采用Optotrak三维运动测量系统连续采集标本运动,分析寰枢椎之间角度运动范围和中性区。结果采用直径3.5 mm的钛棒,2.0 mm的细棒以及3.5 mm的PEEK棒固定后,在前屈、后伸、侧弯和旋转方向上均显著减小了固定节段的运动范围(P<0.05)。直径3.5 mm和2.0 mm的棒固定后的运动范围,在各个方向上无显著性差异。PEEK棒固定的运动范围仅在侧弯方向上大于坚强固定(P=0.005),其他方向无显著性差异。3种固定方式在屈伸、侧弯和旋转方向上均显著减小了固定节段的中性区(P<0.05)。各种固定方式之间相比较,无显著性差异(P>0.05)。结论在寰枢关节采用直径2.0 mm的细棒固定,与坚强固定的稳定性相当。采用直径3.5 mm的PEEK棒固定,在前屈、后伸、旋转方向上与坚强固定的稳定性相当,在侧弯方向上弱于坚强固定。  相似文献   
10.
In the United States, approximately 400,000 patients with acute stroke are discharged annually to inpatient rehabilitation facilities (IRFs) or skilled nursing facilities (SNFs). Typically, IRFs provide time-intensive therapy for an average of 2-3 weeks, whereas SNFs provide more moderately intensive therapy for 4-5 weeks. The factors that influence discharge to an IRF or SNF are multifactorial and poorly understood. The complexity of these factors in combination with subjective clinical indications contributes to large variations in the use of IRFs and SNFs. This has significant financial implications for health care expenditure, given that stroke rehabilitation at IRFs costs approximately double that at SNFs. To control health care spending without compromising outcomes, the Institute of Medicine has stated that policy reforms that promote more efficient use of IRFs and SNFs are critically needed. A major barrier to the formulation of such policies is the highly variable and low-quality evidence for the comparative effectiveness of IRF- vs SNF-based stroke rehabilitation. The current evidence is limited by the inability of observational data to control for residual confounding, which contributes to substantial uncertainty around any magnitude of benefit for IRF- vs SNF-based care. Furthermore, it is unclear which specific patients would receive the most benefit from each setting. A randomized controlled trial addresses these issues, because random treatment allocation facilitates an equitable distribution of measured and unmeasured confounders. We discuss several measurement, practical, and ethical issues of a trial and provide our rationale for design suggestions that overcome some of these issues.  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