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   17054篇
  免费   1501篇
  国内免费   414篇
耳鼻咽喉   303篇
儿科学   252篇
妇产科学   330篇
基础医学   378篇
口腔科学   417篇
临床医学   2639篇
内科学   1686篇
皮肤病学   67篇
神经病学   368篇
特种医学   499篇
外国民族医学   6篇
外科学   5600篇
综合类   2961篇
现状与发展   3篇
预防医学   557篇
眼科学   634篇
药学   794篇
  33篇
中国医学   502篇
肿瘤学   940篇
  2024年   19篇
  2023年   356篇
  2022年   410篇
  2021年   827篇
  2020年   846篇
  2019年   725篇
  2018年   727篇
  2017年   733篇
  2016年   729篇
  2015年   666篇
  2014年   1127篇
  2013年   1055篇
  2012年   824篇
  2011年   969篇
  2010年   750篇
  2009年   769篇
  2008年   768篇
  2007年   788篇
  2006年   845篇
  2005年   765篇
  2004年   582篇
  2003年   494篇
  2002年   434篇
  2001年   368篇
  2000年   294篇
  1999年   274篇
  1998年   212篇
  1997年   201篇
  1996年   176篇
  1995年   158篇
  1994年   156篇
  1993年   124篇
  1992年   89篇
  1991年   91篇
  1990年   82篇
  1989年   65篇
  1988年   55篇
  1987年   59篇
  1986年   50篇
  1985年   52篇
  1984年   52篇
  1983年   39篇
  1982年   50篇
  1981年   26篇
  1980年   21篇
  1979年   20篇
  1978年   18篇
  1977年   17篇
  1976年   5篇
  1975年   6篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
目的探讨风险前瞻应对模式在肝破裂术后患者并发症预防中的应用效果。方法采用便利抽样法,于2019年1月—2020年12月选取在河南省人民医院肝胆外科收治的130例肝破裂患者作为研究对象。将2020年1—12月就诊的65例肝破裂患者作为研究组,采用风险前瞻应对模式进行干预,将2019年1—12月就诊的65例肝破裂患者作为对照组,采用常规方式进行干预。比较两组肝破裂患者手术耐受优良率、术后并发症发生情况及护理满意度。结果研究组患者手术耐受优良率为95.38%(62/65),高于对照组的80.00%(52/65),研究组患者术后并发症总发生率为7.69%(5/65),低于对照组患者的21.54%(14/65),研究组患者护理满意度为95.38%(62/56),高于对照组患者的83.08%(54/65),以上差异均有统计学意义(均P<0.05)。结论在肝破裂围手术期开展风险前瞻应对模式不仅能够提高患者手术耐受性,降低术后并发症发生率,促进护患关系和谐发展。  相似文献   
22.
23.
24.
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   
25.
肠运动存在昼夜节律,表现为白天活跃,夜间减弱或消失,这是一种内生性的、由时钟基因控制的生物节律。肠运动节律既可与中央节律保持高度一致,也可独立于中央节律而对外周环境刺激做出反馈。外科手术会破坏肠运动的昼夜节律,而围手术期合理使用褪黑素、五羟色胺(5-HT)受体激动剂和非甾体类解热镇痛药等药物则有助于促进此节律的恢复。外科医生了解肠运动节律的机制,有助于加深术后肠麻痹(POI)的认识,再基于时辰药理学,在合适的时机以适宜的剂量给药,或许能进一步缩短POI时间,促进肠运动功能尽早恢复。  相似文献   
26.
目的:探讨建立一种放射治疗全身器官剂量数据库平台的可行性。方法:使用基于深度学习的自动勾画软件DeepViewer?1例食管癌患者的全身CT上勾画全身器官,然后利用基于GPU加速的蒙特卡罗软件ARCHER计算相应的器官剂量分布,最后利用Lyman-Kutcher-Burman(LKB)模型评估放疗患者正常组织并发症概率(NTCP)。结果:针对该病例,成功建立基于DeepViewer?ARCHER和LKB模型的全身器官剂量数据库,发现距离靶区越近的器官剂量越大,其中心脏与靶区间距离最小,剂量为14.11 Gy,但因其模型参数特殊,通过LKB模型计算的NTCP为0.00%;左、右肺的剂量分别为3.19和1.16 Gy,但是NTCP值却很大,分别为2.13%和1.60%。对于距离靶区较远的头颈部器官(视交叉、视神经和眼)和腹部器官(直肠、膀胱和股骨头)剂量分别约为9和2 mGy,并且NTCP均近似为0.00%。结论:研究结果证明通过自动勾画软件DeepViewer?蒙特卡罗软件ARCHER和LKB模型建立全身器官剂量数据库的可行性。  相似文献   
27.
It is unclear which criteria should be used to define readiness for tracheal extubation in the operating theatre. We studied the effects of desaturation in the operating theatre immediately after tracheal extubation on long-term outcomes. Performing a pre-specified, retrospective analysis of 71,025 cases involving previously independent adults undergoing non-cardiac surgery, we evaluated the association between desaturation events (oxygen saturation < 90%) within 10 min of tracheal extubation and adverse discharge (to a skilled nursing facility or long-term care facility). A total of 404 (12.3%) cases with, and 5035 (7.4%) cases without, early postoperative desaturation had an adverse discharge. Early postoperative desaturation was associated with higher odds of being discharged to a nursing facility (adjusted odds ratio 1.36 (95%CI 1.20–1.54); p < 0.001). Increased duration of desaturation augmented the effect (p for trend < 0.001). Desaturation was associated with a higher risk of respiratory, renal and cardiovascular complications as well as increased duration of hospital stay, postoperative intensive care unit admission frequency and cost. Several modifiable factors were associated with desaturation including: high intra-operative long-acting opioid administration; high neostigmine dose; high intra-operative inspired oxygen concentration; and low oxygen delivery immediately before tracheal extubation. There was substantial provider variability between anaesthetists in the incidence of postoperative desaturation unexplained by patient- and procedure-related factors. Early postoperative desaturation is a potentially preventable complication associated with a higher risk of adverse discharge disposition. Anaesthetists may consider developing guidelines to define tracheal extubation readiness that contain postoperative desaturation as an adverse outcome after tracheal extubation.  相似文献   
28.
The purpose of this study was to describe a newly developed procedure for temporary mandibulotomy and subsequent osteosynthesis. Clinical outcomes were evaluated, including complications and the impact on postoperative treatment, particularly postoperative radiotherapy. Twenty-four patients underwent temporary mandibulotomies for the surgical resection of malignancies located in the posterior oral or oropharyngeal region. All were treated with postoperative radiotherapy. An angulated median mandibulotomy was followed by osteosynthesis with three anchor screws directed towards the inferior aspect of the mandible. Anchor screws are modified conventional lag screws that include an additional biconcave washer. This modification prevents the screw heads from cracking into the cancellous bone during tightening, improving their biomechanical qualities considerably. Insertion of screws at any angle to the bony surface therefore becomes possible, which is a precondition for this technique. Minor complications occurred in two patients in the early postoperative period. However, complications causing bony non-union, leading to postponed postoperative radiotherapy were not noted in this cohort.  相似文献   
29.

Background

Regional anaesthesia for upper limb surgery is routinely performed with brachial plexus blocks. A retroclavicular brachial plexus block has recently been described, but has not been adequately compared with another approach. This randomised controlled single-blinded trial tested the hypothesis that the retroclavicular approach, when compared with the supraclavicular approach, would increase the success rate.

Methods

One hundred and twenty ASA physical status 1–3 patients undergoing distal upper limb surgery were randomised to receive an ultrasound-guided retroclavicular or supraclavicular brachial plexus block with 30 mL of a 1:1 mixture of mepivacaine 1% and ropivacaine 0.5%, using a single-injection technique without needle tip repositioning. The primary outcome was block success rate 30 min after local anaesthetic injection, defined as a composite score of 14 of 16 points, inclusive of sensory and motor components. Secondary outcomes included needling time, time to first opioid request, oxycodone consumption, and pain scores (numeric rating scale, 0–10) at 24 h postoperatively.

Results

Success rates were 98.3% [95% confidence interval (CI): 90.8%, 99.9%] and 98.3% [95% CI: 90.9%, 99.9%] in the supraclavicular and retroclavicular groups, respectively (P=0.99). The mean needling time was reduced in the supraclavicular group [supraclavicular: 5.0 (95% CI: 4.7, 5.4) min; retroclavicular: 6.0 (95% CI: 5.4, 6.6) min; P=0.006]. The mean time to first opioid request was similar between groups [supraclavicular: 439 (95% CI: 399, 479) min; retroclavicular: 447 (95% CI: 397, 498) min; P=0.19] as were oxycodone consumption [supraclavicular: 10.0 (95% CI: 6.5, 13.5 mg; retroclavicular: 7.9 (95% CI: 4.8, 11.0) mg; P=0.80] and pain scores at 24 h postoperatively [supraclavicular: 1.2 (95% CI: 2.1, 2.7); retroclavicular: 1.5 (95% CI: 1.6, 2.4); P=0.09].

Conclusions

Ultrasound-guided retroclavicular and supraclavicular brachial plexus blocks share identical success rates, while providing similar pain relief. Reduced needling time in the supraclavicular approach is not clinically relevant.

Clinical trial registration

NCT02641613.  相似文献   
30.
Purpose: To investigate clinical features, visual prognosis, and ocular complications in patients with ankylosing spondylitis (AS)-associated anterior uveitis (AU).

Methods: Data of 211 eyes of 145 patients with AU associated with AS were reviewed retrospectively.

Results: Mean follow-up time was 6.31 ± 6.33 years. Men were younger than women at AS diagnosis (= 0.035). The mean number of uveitis flares was highest during the first quarter of the year and lowest during the third quarter (= 0.017). Immunosuppressive agent use was higher in women than men (= 0.052). Ocular complications developed in 120 eyes (56.9%), and the complication rate was 0.146/eye year. Males developed cystoid macular edema more frequently than females (= 0.05). Glaucoma was observed more often in early-onset disease (age at AS onset <45 years) than late-onset disease (= 0.028).

Conclusions: Visual prognosis of AU in patients with AS was good, although more than half of the eyes developed ocular complications (56.9%).  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