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   65423篇
  免费   4614篇
  国内免费   1819篇
耳鼻咽喉   429篇
儿科学   943篇
妇产科学   588篇
基础医学   7655篇
口腔科学   1091篇
临床医学   6094篇
内科学   6665篇
皮肤病学   374篇
神经病学   8811篇
特种医学   2062篇
外国民族医学   2篇
外科学   4536篇
综合类   10422篇
现状与发展   6篇
预防医学   9459篇
眼科学   702篇
药学   7376篇
  96篇
中国医学   2270篇
肿瘤学   2275篇
  2024年   81篇
  2023年   940篇
  2022年   1335篇
  2021年   2386篇
  2020年   2406篇
  2019年   1846篇
  2018年   1820篇
  2017年   1853篇
  2016年   2076篇
  2015年   2071篇
  2014年   4226篇
  2013年   4640篇
  2012年   4107篇
  2011年   4472篇
  2010年   3518篇
  2009年   3408篇
  2008年   3500篇
  2007年   3297篇
  2006年   2995篇
  2005年   2533篇
  2004年   2111篇
  2003年   1863篇
  2002年   1466篇
  2001年   1273篇
  2000年   1069篇
  1999年   863篇
  1998年   799篇
  1997年   767篇
  1996年   632篇
  1995年   685篇
  1994年   669篇
  1993年   588篇
  1992年   552篇
  1991年   537篇
  1990年   444篇
  1989年   390篇
  1988年   402篇
  1987年   377篇
  1986年   346篇
  1985年   468篇
  1984年   396篇
  1983年   243篇
  1982年   265篇
  1981年   243篇
  1980年   227篇
  1979年   145篇
  1978年   135篇
  1977年   120篇
  1976年   87篇
  1974年   45篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
81.
《Foot and Ankle Surgery》2022,28(7):950-955
BackgroundLength change pattern of the ankle deltoid ligament during physiological ankle motion is still confused currently and had not been studied in vivo.MethodsThe deltoid ligaments from 7 cadaveric specimens were dissected. Lengths of each band during 30° plantarflexion to 20° dorsiflexion were measured. A dual fluoroscopy imaging system was utilized to capture the images of hindfoot joint of 7 healthy subjects during the stance phase of walking. 3D bone models were reconstructed from CT images. Lengths of each band were calculated after model-image registration utilizing a solid modeling software. Percentage of length variation and poses when the bands were in maximum extension were documented among each band.ResultsThe anterior border of tibiocalcaneal ligament (TCL) had only 1.7% length variation in vitro and 5.7% length variation in vivo. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension at 30° plantarflexion, however, superficial posterior tibiotalar ligament, deep posterior tibiotalar ligament, and the posterior border of TCL were in maximum extension at 20° dorsiflexion. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension during foot flat. The TCL was in maximum extension during midstance. The superficial posterior tibiotalar ligament and deep posterior tibiotalar ligament were in maximum extension during heel off and toe off.ConclusionThe length of TCL did not change during ankle dorsiflexion and plantarflexion. The bands anterior to and posterior to the TCL showed different length change pattern during physiological ankle dorsiflexion and plantarflexion.  相似文献   
82.
以江苏省人民医院为例,介绍医院门诊分诊叫号系统设计。从软硬件实现两方面阐述系统整体架构、具体功能和应用实践,指出该系统有助于改善门诊就医环境、减轻医护人员工作压力、提升患者满意度。  相似文献   
83.
医联体是指一定地域内不同类型层级的公立医疗机构组合起来,成立协作联盟或组建医疗集团,成为利益共同体和责任共同体,即实现金字塔格局的分层诊疗模式。本文以人才流动理论着手,以XX医院医联体"送下去、请上来"的基层单位临床骨干人才的培养方式为例,结合SWOT分析法,SWOT分析法是是一种能够较客观而准确地分析和研究一个组织或单位发展现状的研究方法 ,对该模式的内外部资源以及环境展开分析,探寻为院医联体基层单位临床人才培养的相关制度,为医联体人才培养提供依据,同时探讨该举措在培养医联体成员单位临床骨干人才的作用及需要改进的方面,从积极争取支持、设立集团内绩效制度、实现文化理念相结合、加速信息共享平台的建设等方面进行改善。  相似文献   
84.
ObjectiveIn traditional medicine, the seeds of Thai Mucuna pruriens (T-MP) are used to treat male dysuria and are believed to enhance fertility. However, information pertaining to the toxicity of T-MP and its interaction with other properties is limited. This study was thus conducted to evaluate the antioxidant capacity and subacute toxicity of T-MP in the reproductive system.MethodsTotal phenolic content and antioxidant capacity of T-MP seed extract were determined using total phenolic content, 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assays. Male and female adult rats were treated orally with T-MP at a dosage of 150 or 300 mg/kg body weight for 14 consecutive days. Sex hormones and functional parameters in the liver and kidney were evaluated. Histopathology of all tissue was conducted using Masson’s trichrome staining. Sperm parameters, including concentration, morphology, acrosome reaction status and DNA damage, were also examined. Expression of tyrosine phosphorylated protein (TyrPho), androgen receptor and A-kinase-anchoring protein 4 (AKAP4) were investigated using the Western blot technique.ResultsT-MP seed extract contained phenolic compounds and exhibited high antioxidant capacity with no toxicity at the tested doses. It did not affect liver or kidney function parameters in the male rats, but increased estradiol, aspartate aminotransferase and alanine aminotransferase levels in the females. Additionally, it decreased serum progesterone and alkaline phosphatase levels in female rats. Serum and intratesticular testosterone levels were significantly lower in male rats that received a high dosage of T-MP. Histopathological changes were not observed in any tissue treated with T-MP. T-MP also significantly increased sperm concentration (but did not affect sperm parameters), and enhanced testicular TyrPho protein and androgen receptor and expression of AKAP4 in sperms.ConclusionT-MP seed extract exhibited antioxidant capacity and was not harmful to reproductive tissues. It also had a phytoestrogenic effect on females and increased the expression of testicular and sperm markers of male fertility.  相似文献   
85.
86.
ABSTRACT

Introduction

Fifteen percent of proliferating infantile hemangioma (IH) require intervention because of the threat to function or life, ulceration, or tissue distortion. Propranolol is the mainstay treatment for problematic proliferating IH. Other β-blockers and angiotensin-converting enzyme (ACE) inhibitors have been explored as alternative treatments.  相似文献   
87.
ObjectiveThe American Joint Committee on Cancer 8th edition staging system presents separate classifications for pTNM and post-neoadjuvant ypTNM (ypTNM-8th) to enhance prognostic prediction after neoadjuvant therapy and surgery. We aimed to validate the ypTNM-8th staging system and to compare the prognostication performance of ypTNM-8th with that of pTNM-7th and pTNM-8th in esophageal squamous cell carcinoma (ESCC) patients receiving neoadjuvant chemoradiotherapy (nCRT).MethodsWe reviewed 207 ESCC patients treated with nCRT between January 2007 and December 2014 and compared the Akaike information criterion (AIC) and Harrell's C-index to determine the prognostic performance of each TNM system.ResultsSurvival curve analysis of pTNM-7th and -8th showed a stepwise drop in survival from ypT0N0 to advanced stages, whereas the survival outcome of ypStage III showed a better prognosis than that of ypStage II according to ypTNM-8th. Lymphovascular invasion, perineural invasion, and tumor regression grade were significantly associated with overall survival on univariate analysis. Each TNM system showed significant p-values for trend (p < 0.0001 each), but after adjusting for prognostic factors, ypTNM-8th did not significantly predict survival (p = 0.15), whereas pTNM-7th remained significant (p < 0.001). pTNM-7th incorporating ypT0N0M0 and ypT0 (is)N + M0 as separate groups was superior in prognostication as its AIC was smaller and its C-index was higher than those of pTNM-8th and ypTNM-8th, respectively.ConclusionsBecause ypTNM-8th did not provide sufficient prognostication for patients with ESCC treated with nCRT followed by esophagectomy, more sophisticated prognostic classification should be developed for the ypTNM staging system in these patients.  相似文献   
88.
IntroductionIn Mexico, there are considerable health system delays in the diagnosis and treatment initiation of women with breast cancer. Alerta Rosa is a navigation program in Nuevo Leon that aims to reduce barriers that impede the timely management of these patients.Patients and MethodsSince December 2017, women who registered to receive medical evaluations by Alerta Rosa were stratified based on their clinical characteristics into three priority groups (“Red,” “Yellow,” and “Green”). According to the category assigned, patients were scheduled imaging studies and medical appointments with breast specialists on a preferential basis.ResultsUp until December 2019, 561 patients were scheduled for medical evaluations. Of them, 59% were classified as “Red,” 25% “Yellow,” and 16% “Green” priority. The median time from stratification to first medical evaluation was 4, 6, and 7 days, respectively (p = .003). Excluding those who had a prior breast cancer diagnosis, 21 patients were diagnosed by Alerta Rosa, with the initial “Red” priority classification demonstrating a sensitivity of 95% (95% confidence interval [CI], 75.1%–99.9%) and specificity of 42% (95% CI, 37.1%–47.1%) for breast cancer. The median time elapsed from initial patient contact to diagnosis and treatment initiation was 16 days and 39 days, respectively. The majority (72%) of patients were diagnosed at an early stage (0–II).ConclusionThis patient prioritization system adequately identified women with different probabilities of having breast cancer. Efforts to replicate similar triage systems in resource‐constrained settings where screening programs are ineffective could prove to be beneficial in reducing diagnostic intervals and achieving early‐stage diagnoses.Implications for PracticeLow‐ and middle‐income countries such as Mexico currently lack the infrastructure to achieve effective breast cancer screening and guarantee prompt access to health care when required. To reduce the disease burden in such settings, strategies targeting early detection are urgently needed. Patient navigation programs aid in the reduction of health system intervals and optimize the use of available resources. This article presents the introduction of a triage system based on initial patient concern. Appointment prioritization proved to be successful at reducing health system intervals and achieving early‐stage diagnoses by overcoming barriers that impede early access to quality medical care.  相似文献   
89.
BACKGROUND Accurate detection of gastric infection by Helicobacter pylori(H.pylori) and premalignant lesions are important for effective provision of treatment,preventing the development of gastric neoplasia.Optical enhancement systems with optical magnification improved the identification of mucosal superficial and vascular patterns in patients with dyspepsia.AIM To evaluate an optical enhancement system with high-definition magnification,for diagnosis of normal gastric mucosa,H.pylori-associated gastritis,and gastric atrophy.METHODS A cross-sectional,nonrandomized study from November 2015 to April 2016 performed in a single-tertiary academic center from Ecuador.Seventy-two consecutive patients with functional dyspepsia according to the Rome III criteria,were tested for H.pylori using a stool antigen test and were assigned to an Hp+group or an Hp-control group.Esophagogastroduodenoscopy with highdefinition optical magnification and digital chromoendoscopy was performed,and patients were classified into 4 groups,in accordance to the microvasculararchitecture pattern of the mucosa.Interobserver and intraobserver agreement among operators were calculated.RESULTS Of the 72 participants,35 were Hp+ and 37 were Hp-.Among 10 patients with normal mucosal histology in biopsy samples,90% had a Type I pattern of microvascular architecture by endoscopy.Among participants with type IIa and type IIb patterns,significantly more were Hp+ than Hp-(32 vs 8),and most(31 out of 40) had histological diagnoses of chronic active gastritis.Two of the three participants with a histological diagnosis of atrophy had a type III microvascular pattern.The type I pattern predicted normal mucosa,type IIa–IIb predicted H.pylori infection,and type III predicted atrophy with sensitivities of 90.0%,91.4%,and 66.7%,respectively.The intraobserver and interobserver agreements had kappa values of 0.91 and 0.89,respectively.CONCLUSION High-definition optical magnification with digital chromoendoscopy is useful for diagnosis of normal gastric mucosa and H.pylori-associated gastritis with high accuracy,but further studies are needed to determine whether endoscopic diagnosis of gastric atrophy is feasible.  相似文献   
90.
《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.  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