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   221634篇
  免费   17202篇
  国内免费   5066篇
耳鼻咽喉   1614篇
儿科学   3166篇
妇产科学   5364篇
基础医学   26403篇
口腔科学   4078篇
临床医学   16446篇
内科学   25482篇
皮肤病学   2546篇
神经病学   13451篇
特种医学   7381篇
外国民族医学   25篇
外科学   18608篇
综合类   33354篇
现状与发展   27篇
一般理论   10篇
预防医学   18608篇
眼科学   2935篇
药学   28823篇
  125篇
中国医学   18712篇
肿瘤学   16744篇
  2023年   2752篇
  2022年   3999篇
  2021年   8295篇
  2020年   7670篇
  2019年   7605篇
  2018年   7512篇
  2017年   8272篇
  2016年   8386篇
  2015年   8020篇
  2014年   10793篇
  2013年   13966篇
  2012年   11859篇
  2011年   14221篇
  2010年   10162篇
  2009年   8910篇
  2008年   10231篇
  2007年   11468篇
  2006年   10721篇
  2005年   9586篇
  2004年   8125篇
  2003年   7423篇
  2002年   5670篇
  2001年   5206篇
  2000年   4260篇
  1999年   3552篇
  1998年   2641篇
  1997年   2679篇
  1996年   2461篇
  1995年   2346篇
  1994年   2267篇
  1993年   1852篇
  1992年   1724篇
  1991年   1599篇
  1990年   1382篇
  1989年   1135篇
  1988年   1088篇
  1987年   974篇
  1986年   902篇
  1985年   1679篇
  1984年   1529篇
  1983年   1110篇
  1982年   1173篇
  1981年   1051篇
  1980年   999篇
  1979年   855篇
  1978年   646篇
  1977年   466篇
  1976年   531篇
  1975年   439篇
  1974年   342篇
排序方式: 共有10000条查询结果,搜索用时 32 毫秒
1.
BackgroundPerianal abscesses and anal fistulas are common. The principle of intention-to-treat has not been considered in previous systemic reviews. Thus, the comparison between primary and post-recurrence management was confused, and the recommendation of primary treatment is obscure. The current study aims to identify the optimal initial treatment for pediatric patients.MethodsUsing PRISMA guidelines, studies were identified from MEDLINE, EMBASE, PubMed, Cochrane Library, and Google Scholar without any language or study design restriction. The inclusion criteria include original articles or articles with original data, studies of management for a perianal abscess with or without anal fistula, and patient age of <18 years. Patients with local malignancy, Crohn's disease, or other underlying predisposing conditions were excluded. Studies without analyzing recurrence, case series of <5, and irrelevant articles were excluded in the screening stage. Of the 124 screened articles, 14 articles had no full texts or detailed information. Articles written in a language other than English or Mandarin were translated by Google Translation first and confirmed with native speakers. After the eligibility process, studies that compared identified primary managements were then included in the qualitative synthesis.ResultsThirty-one studies involving 2507 pediatric patients met the inclusion criteria. The study design consisted of two prospective case series of 47 patients and retrospective cohort studies. No randomized control trials were identified. Meta-analyses for recurrence after initial management were performed with a random-effects model. Conservative treatment and drainage revealed no difference (Odds ratio [OR], 1.222; 95% Confidential interval [CI]: 0.615–2.427, p = 0.567). Conservative management had a higher risk of recurrence than surgery without statistical significance (OR 0.278, 95% CI: 0.109–0.707, p = 0.007). Compared with incision/drainage, surgery can prevent recurrence remarkably (OR 4.360, 95% CI: 1.761–10.792, p = 0.001). Subgroup analysis of different approaches within conservative treatment and operation was not performed for lacking information.ConclusionStrong recommendations cannot be made due to the lack of prospective or randomized controlled studies. However, the current study based on real primary management supports initial surgical intervention for pediatric patients with perianal abscesses and anal fistula to prevent recurrence.Level of evidenceType of study: Systemic review; Evidence level: Level II.  相似文献   
2.
目的:分析子野个数限值对宫颈癌固定野调强放疗(fixed-field intensity-modulated radiotherapy,ff-IMRT)计划的影响,寻求最优的子野个数限值。方法:选取10例接受ff-IMRT的宫颈癌患者,基于Monaco 5.11.03计划系统,以45 Gy/25 f处方剂量分别对同一患者设计8种ff-IMRT计划(ff-IMRT计划依据子野个数限值命名,子野个数限值分别为40、60、70、80、100、120、130、150),采用SPSS 20.0软件比较除plan100之外7个ff-IMRT计划与plan100剂量学参数、优化时间和治疗参数的差异。结果:8种ff-IMRT计划归一化后,plan40和plan60的D2%、Dmin、CI和HI均劣于plan100(P<0.05)。8种ff-IMRT计划均能较好保护危及器官(organ at risk,OAR)和正常组织。plan40小肠V45;plan40和plan60小肠D2cc,直肠、膀胱V45、D40%,两侧股骨头V40和正常组织 V35、V40均高于plan100(P<0.05)。plan40和plan60优化时间、治疗参数均优于plan100(P<0.05);plan120、plan130和plan150子野面积、子野个数(51~150 cm2和>150 cm2)和出束时间均劣于plan100(P<0.05)。结论:子野个数限值为70~100时,ff-IMRT计划能兼顾剂量学参数满足临床要求、优化时间和治疗参数最优化,建议在设计宫颈癌ff-IMRT计划时在该范围内设置子野个数限值。  相似文献   
3.
4.
5.
6.
目的:观察评判性护理干预对乳腺癌手术后患者疼痛和睡眠质量的影响。方法:选取2019年1月至2020年5月蚌埠医学院第一附属医院肿瘤内科收治的乳腺癌手术患者126例作为研究对象,按照随机数字表法分为观察组和对照组,每组63例。对照组给予常规护理干预,观察组给予评判性护理干预。采用抑郁自评量表(Self-rating Depression Scale,SDS)、焦虑自评量表(Self-rating Anxiety Scale,SAS)比较2组患者干预前后抑郁、焦虑状态改善情况,采用匹兹堡睡眠指数量表(Pittsburgh Sleep Quality Index,PSQI)比较2组患者睡眠质量变化,同时观察2组患者并发症发生率、中度、重度疼痛患者所占比例。结果:干预后,观察组SAS评分、SDS评分显著低于对照组,观察组PSQI评分显著低于对照组,患者中度、重度疼痛比例降低,并发症发生率降低,观察组的干预效果优于对照组,2组比较差异有统计学意义(P<0.05)。结论:对乳腺癌患者手术后采用评判性护理,可有效缓解患者手术后疼痛程度,改善患者睡眠质量,降低患者焦虑及抑郁情绪,降低并发症发生风险,值得推广使用。  相似文献   
7.
《Radiography》2022,28(2):353-359
Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.  相似文献   
8.
9.
目的 测定儿童1型糖尿病(T1DM)患者骨密度(BMD),分析探讨骨密度变化的影响因素。方法 选取于2018年1月—2021年6月于我院收治的儿童1型糖尿病患者76例,收集性别、年龄、发病年龄、身高、体重、BMI、病程等基本资料,检测空腹血糖、空腹C肽、糖化血红蛋白(HbA1c)、血碳酸氢根(HCO3-)、血清碱性磷酸酶(ALP),应用双能X线吸收测定法测定骨密度,获取Z值。结果 76例儿童1型糖尿病患者骨密度Z值为-0.93±2.14。HbA1c、病程与骨密度Z值呈负相关,差异具有统计学意义(分别B=-0.334,P<0.001;B=-0.191,P=0.017)。结论 儿童1型糖尿病患者骨密度低于健康儿童,血糖控制不良、病程长是1型糖尿病儿童骨密度减低的危险因素。  相似文献   
10.
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