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   4490篇
  免费   270篇
  国内免费   56篇
耳鼻咽喉   85篇
儿科学   62篇
妇产科学   26篇
基础医学   710篇
口腔科学   83篇
临床医学   447篇
内科学   411篇
皮肤病学   22篇
神经病学   1234篇
特种医学   72篇
外国民族医学   1篇
外科学   265篇
综合类   458篇
预防医学   502篇
眼科学   112篇
药学   224篇
  4篇
中国医学   31篇
肿瘤学   67篇
  2023年   54篇
  2022年   56篇
  2021年   120篇
  2020年   152篇
  2019年   118篇
  2018年   137篇
  2017年   148篇
  2016年   142篇
  2015年   117篇
  2014年   211篇
  2013年   262篇
  2012年   237篇
  2011年   241篇
  2010年   187篇
  2009年   155篇
  2008年   173篇
  2007年   144篇
  2006年   150篇
  2005年   109篇
  2004年   104篇
  2003年   124篇
  2002年   93篇
  2001年   102篇
  2000年   81篇
  1999年   67篇
  1998年   75篇
  1997年   77篇
  1996年   61篇
  1995年   93篇
  1994年   73篇
  1993年   69篇
  1992年   65篇
  1991年   82篇
  1990年   50篇
  1989年   56篇
  1988年   58篇
  1987年   46篇
  1986年   63篇
  1985年   78篇
  1984年   54篇
  1983年   60篇
  1982年   55篇
  1981年   40篇
  1980年   40篇
  1979年   27篇
  1978年   21篇
  1977年   19篇
  1976年   26篇
  1975年   8篇
  1974年   19篇
排序方式: 共有4816条查询结果,搜索用时 15 毫秒
1.
Background: Considering the poor prognosis of non-small cell lung cancer (NSCLC), the objective of this study was to examine the potential of plasma-derived vesicles as a source of lung cancer-specific proteins. Extracellular vesicle (EV) cargos are specific to the source cells, hence they have the potential of being a source of cancer-specific proteins.  Methods: The proteins differently expressed in cancer were determined and derived from EVs isolated from the plasma of NSCLC patients at the National Lung Hospital. To this end, purification was done using gel filtration chromatography and ultracentrifugation. In addition, nano liquid chromatography mass spectrometry (LC–MS/MS) was used for analyzing. Results: Fifty-seven EV-derived proteins related to NSCLC were highlighted in this research. Some of them have not been addressed before, such as EEF1A1 (elongation factor 1-α1), KPNB1 (Importin subunit beta 1), SRC (proto-oncogene tyrosine-protein kinase) and ACTC1 (actin, alpha cardiac muscle 1). This list was further confirmed through a comparison with ExoCarta and Vesiclepedia. Conclusion: This study is the first work to show the involvement of several novel proteins of small EV (EEF1A1, KPNB1, SRC, and ACTC1) in the progression of NSCLC. The results suggested that they could serve as novel biomarkers for non-small cell lung cancer in the future.  相似文献   
2.
Objective: To observe the effects and safety of Tongyan Spray (通咽喷雾剂) on the range and time of hyoid motion in patients with ischemic post-stroke dysphagia. Methods: Seventy-two patients with ischemic post-stroke dysphagia were selected and randomly assigned to a treatment group (36 cases) and a control group (36 cases) by a random number table from January 2013 to October 2014. All patients swallowed 4 kinds of barium meals with different traits respectively, and each patient underwent video fluoroscopy (VF) examination twice. In the treatment group, Tongyan Spray was sprayed to the pharynx on both sides and the middle part once respectively. The spray was applied 30 min before the second examination. Purified water at room temperature was used as placebo in the control group. The changes in the range and time of hyoid motion in both groups were observed before and after treatment. Results: Six patients dropped out in each group, and 60 patients completed the study and were included in the final analysis. Significant improvement was observed in the range of superior hyoid excursion distance and the time of hyoid motion in the treatment group compared with the control group (P<0.05). There were no obvious adverse reactions observed in oral mucosa in both groups during the whole study. Conclusion: Tongyan Spray was an effective and safe medicine for improving swallowing function in patients with ischemic post-stroke dysphagia.  相似文献   
3.
目的探讨应用微视频对ICU气管套管带管出院患者的家属实施健康教育的效果。方法选取2018年9月—2020年9月的100例气管套管带管出院患者的家属,根据随机数字表法将其随机分为对照组和试验组各50例,对照组实施常规健康教育和随访;试验组在此基础上将患者出院后面临的共性问题进行归纳总结,制定并应用微视频对其实施健康教育。分别比较两组患者家属在气管套管相关知识知晓率、气管套管护理操作的准确性以及患者气管切开并发症发生率之间的差异。结果试验组家属在气管套管相关知识的知晓率和护理技能的得分均高于对照组家属(P<0.05),但患者气管切开相关并发症发生率低于对照组(P<0.05)。结论应用微视频实施健康教育可有效提高ICU气管套管带管出院患者家属的管路护理水平,提高患者带管期间的安全性。  相似文献   
4.
目的:探讨单孔胸腔镜下肺癌手术术后胸腔引流时间的影响因素。方法:本研究采用回顾性分析方法,回顾我院2018年01月至2019年12月原发性肺癌患者经单孔胸腔镜手术治疗的病例199例。按照术后胸腔引流时间分为两组,Ⅰ组(术后胸腔引流时间<5天)和Ⅱ组(术后胸腔引流时间≥5天)。对于影响术后胸腔引流时间的可能因素在两组间先采用单因素分析的方法筛选,再将筛选出来的对术后胸腔引流时间可能有意义的影响因素进行二项Logistic多因素回归分析。结果:经单因素分析及二项Logistic多因素回归分析结果显示:年龄≥60岁、手术部位、肺段切除术、胸膜粘连、手术时间≥180 min、术后早期下床活动是术后胸腔引流时间的独立影响因素(P<0.05)。结论:对于具有多个延长术后胸腔引流时间的独立影响因素的患者,应制定个体化管理方案,尽可能减少术后胸腔引流时间,减少住院天数,加快患者康复。  相似文献   
5.
目的评估猪尾巴导管在单孔胸腔镜肺肿瘤手术中应用的有效性。方法回顾性分析2020年1月至12月上海交通大学医学院附属仁济医院东院接受单孔胸腔镜肺肿瘤手术的患者共441例,根据是否放置猪尾巴导管分为胸管组和猪尾巴管组,通过倾向性评分匹配法进行1∶1匹配,对比两组患者围手术期的各项指标。结果匹配后每组143例配对成功,匹配后两组间基线特征无统计学差异。对比两组围手术期指标发现,猪尾巴管组患者术后3天胸腔引流总量显著多于胸管组(375.49 ml对285.03 ml,P<0.001),术后两周复查CT示胸腔积液量显著少于胸管组(131.77 ml对178.84 ml,P=0.032),两组术后疼痛评分、引流天数及住院天数无明显统计学差异。结论加放猪尾巴导管可有效改善单孔胸腔镜肺肿瘤术后胸腔引流情况,且不增加患者术后疼痛,不延长胸腔引流及住院天数。  相似文献   
6.
Generalized tonic status epilepticus (TSE) is a rare epileptic condition. It occurs usually in the context of symptomatic generalized epilepsy, in particular, in subjects with a diagnosis of Lennox‐Gastaut syndrome, atypical forms of idiopathic (genetic) generalized epilepsy, or as a paradoxical effect during treatment with diverse antiepileptic drugs. Herein, we describe the case of an elderly woman on chronic treatment with psychotropic drugs who developed an episode of generalized TSE. Motor manifestations were subtle and difficult to recognize as seizures, and a detailed video‐EEG importantly contributed to accurate and prompt diagnosis. TSE was initially refractory to conventional anti‐seizure drug therapy including levetiracetam and valproate but was finally controlled with lacosamide. Our case indicates a potential therapeutic effect of lacosamide on TSE in the elderly after treatment failure with first‐line anti‐seizure drugs. [Published with video sequence on www.epilepticdisorders.com ]  相似文献   
7.
Small‐bowel capsule endoscopy (SBCE) is used widely because of its non‐invasive and patient‐friendly nature. SBCE can visualize entire small‐intestinal mucosa and facilitate detection of small‐intestinal abnormalities. In this review article, we focus on the current status of SBCE. Several platforms for SBCE are available worldwide. Third‐generation SBCE (PillCam® SB3) has a high‐resolution camera equipped with an adaptive frame rate system. Several software modes have been developed to reduce the reading time for capsule endoscopy and to minimize the possibility of missing lesions. The main complication of SBCE is capsule retention. Thus, the main contraindication for SBCE is known or suspected gastrointestinal obstruction unless intestinal patency is proven. Possible indications for SBCE are obscure gastrointestinal bleeding, Crohn's disease, small‐intestinal polyps and tumors, and celiac disease. Colon capsule endoscopy (CCE) can observe inflamed colonic mucosa non‐invasively, and allows for the continuous and non‐invasive observation of the entire intestinal tract (pan‐endoscopy). Recently, application of CCE as pan‐enteric endoscopy for inflammatory bowel diseases (including Crohn's disease) has been reported. In the near future, reading for CE will be assisted by artificial intelligence, and reading CE videos for long periods will not be required.  相似文献   
8.
9.
Background: Studies have demonstrated inconsistent results regarding the association between video gaming time and substance use in teenagers. Understating intricacies of this association can help with substance use reduction in teenagers. Objectives: This study aimed to untangle this complex relationship by theorizing and examining a U-shaped association. Methods: We analyzed two large samples (n1 = 7313 [52.5% female] and n2 = 8079 [51.6% female]) of 8th and 10th graders in the United States. Substance use was operationalized as the sum of self-reported number of lifetime use instances of 14 unprescribed substances. Video game use time (hours per week) was self-reported on a 1 (none) to 9 (40+) scale. Common covariates/risk factors were included. Results: Consistently across datasets, partial-correlation between squared video gaming time and substance use (r?=?.10, p?<?.001 in 2014 and r?=?.08, p?<?.001 in 2015) supported the hypothesized u-shaped association. Analysis of covariance revealed that teenagers playing video games for 1–5?h a week report on significantly fewer instances of substance use compared with non-gamers (p?<?.001–.007). Post hoc analyses revealed that those who play at least 30?h per week report on significantly (p?<?.001) more instances of substance use (3.92 in 2014 and 3.38 in 2015) compared with teenagers playing video games for 1–5?h a week (2.17 in 2015 and 1.96 in 2015). Conclusions: Video gaming time and substance use follow a u-shaped association; light video gaming can be protective in terms of substance use, while too much video gaming is associated with increased substance use.  相似文献   
10.
《Foot and Ankle Surgery》2020,26(4):371-377
BackgroundA good recovery of the physiological mobility of the ankle is an indication of patients’ satisfaction after total ankle arthroplasty, which does not generally match that of other consolidated procedures such as hip and knee replacement. The aim of this study was to investigate the kinematics of the Zimmer Total Metal Total Ankle (ZTMTA) during the different exercises.MethodsFifteen patients with ZTMTA were enrolled in this study. The patients performed non-weightbearing flexion-extension, stair climbing and descending, and fluoroscopic images were taken to capture the ankle movements. A combined images/three-dimensional models method was used to perform a kinematic analysis.ResultsPlantar-dorsiflexion resulted the main plane of movement, with the largest range of motion (ROM) of 23.3 ± 9.0° during flexion-extension. Inversion–eversion and adduction–abduction resulted lower than 10° in any trials.ConclusionsIn the investigated population, the ZTMTA allowed a good recovery of the mobility, with ROMs comparable to the healthy subjects.  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