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   11970篇
  免费   640篇
  国内免费   157篇
耳鼻咽喉   128篇
儿科学   250篇
妇产科学   150篇
基础医学   787篇
口腔科学   142篇
临床医学   1392篇
内科学   1160篇
皮肤病学   101篇
神经病学   733篇
特种医学   196篇
外国民族医学   1篇
外科学   1871篇
综合类   2302篇
现状与发展   1篇
一般理论   3篇
预防医学   1340篇
眼科学   240篇
药学   995篇
  8篇
中国医学   273篇
肿瘤学   694篇
  2024年   9篇
  2023年   91篇
  2022年   179篇
  2021年   291篇
  2020年   264篇
  2019年   234篇
  2018年   221篇
  2017年   219篇
  2016年   261篇
  2015年   370篇
  2014年   715篇
  2013年   859篇
  2012年   715篇
  2011年   734篇
  2010年   701篇
  2009年   668篇
  2008年   660篇
  2007年   734篇
  2006年   672篇
  2005年   505篇
  2004年   499篇
  2003年   425篇
  2002年   407篇
  2001年   342篇
  2000年   286篇
  1999年   224篇
  1998年   213篇
  1997年   190篇
  1996年   156篇
  1995年   114篇
  1994年   102篇
  1993年   106篇
  1992年   77篇
  1991年   84篇
  1990年   59篇
  1989年   37篇
  1988年   43篇
  1987年   38篇
  1986年   38篇
  1985年   47篇
  1984年   34篇
  1983年   16篇
  1982年   20篇
  1981年   18篇
  1980年   22篇
  1979年   17篇
  1978年   19篇
  1977年   10篇
  1976年   6篇
  1975年   6篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
3.
Background/PurposeA small number of Hirschsprung disease (HD) patients develop inflammatory bowel disease (IBD)-like symptoms after pullthrough surgery. The etiology and pathophysiology of Hirschsprung-associated IBD (HD-IBD) remains unknown. This study aims to further characterize HD-IBD, to identify potential risk factors and to evaluate response to treatment in a large group of patients.MethodsRetrospective study of patients diagnosed with IBD after pullthrough surgery between 2000 and 2021 at 17 institutions. Data regarding clinical presentation and course of HD and IBD were reviewed. Effectiveness of medical therapy for IBD was recorded using a Likert scale.ResultsThere were 55 patients (78% male). 50% (n = 28) had long segment disease. Hirschsprung-associated enterocolitis (HAEC) was reported in 68% (n = 36). Ten patients (18%) had Trisomy 21. IBD was diagnosed after age 5 in 63% (n = 34). IBD presentation consisted of colonic or small bowel inflammation resembling IBD in 69% (n = 38), unexplained or persistent fistula in 18% (n = 10) and unexplained HAEC >5 years old or unresponsive to standard treatment in 13% (n = 7). Biological agents were the most effective (80%) medications. A third of patients required a surgical procedure for IBD.ConclusionMore than half of the patients were diagnosed with HD-IBD after 5 years old. Long segment disease, HAEC after pull through operation and trisomy 21 may represent risk factors for this condition. Investigation for possible IBD should be considered in children with unexplained fistulae, HAEC beyond the age of 5 or unresponsive to standard therapy, and symptoms suggestive of IBD. Biological agents were the most effective medical treatment.Level of EvidenceLevel 4  相似文献   
4.
目的对某跨区域医联体核心医院的运行效率进行评价,以不完全契约理论为分析视角探讨影响因素,为深化医联体建设提供借鉴和参考。方法收集2014年-2021年核心医院相关数据,采用DEA数据分析方法,计算运行效率变化情况。结果核心医院各项投入明显增加,医疗业务产出同步增长,医院运行效率经历了动态波动后持续向好。结论通过构建管理共同体,逐步优化契约,争取医保政策支持,合作共建初见成效。  相似文献   
5.
6.
《Educación Médica》2020,21(6):403-409
A presentation is made of 12 cases that have a full and detailed clinical history and physical examination, which are essential for obtaining optimal diagnostic-therapeutic planning for quality care. Furthermoe, education in values focused on the patient is considered as another of the essential objectives to be transmitted in university faculties and hospitals. This article, based on anonymised real cases, aims to provide small brushstrokes in this regard, hoping that they will be useful.  相似文献   
7.
The midwifery art has emphasised the uniqueness of human beings throughout its Nordic history. The educated Nordic midwife has in the last decade celebrated several hundred years of memories. This article studies how the key ideas of the midwifery art and patterns of ideas become evident in the zeitgeist from the beginning of the 19th century to the millennium in the Nordic countries. The legacy and pattern of ideas of the art of midwifery are interpreted in relation to the texts of the selected historical sources and based on Ricoeur's phenomenological-hermeneutic approach to the text and further to the dedication of understanding and interpretation. The historical sources refer to unprinted primary sources from historical archives and printed secondary and tertiary sources. The patterns of ideas include a tripartite whole: the true cultivation of the head, the philosophy and aesthetics of the hand, the strength of the heart and the drive of calling. These ideas open for unique visions and attest to the evident in modern midwives. Today's midwives have academic training with examinations, and the education is based on scientific evidence. The midwife profession is authorised by the state and supervised by the authorities.  相似文献   
8.
Introduction and objectivesDeterminants of chronic obstructive pulmonary disease (COPD) in the early stages of its natural history are not well known. Improving our knowledge of these factors will help to design interventions that can modify prognosis.Study objectives are: a) to characterize a COPD population of young adults aged 35-50 years from a multidimensional point of view; b) to compare these patients with smokers with normal lung function; and c) to create a cohort of young adults aged 35-50 years (smokers or former smokers), with and without COPD, who will be followed in the future to improve understanding of the natural history of the disease.Participants and methodThis is a case-control multicenter study aimed at establishing a well-characterized cohort of young adults, smokers or former-smokers, with and without COPD, for subsequent follow-up.A total of 311 participants (101 cases and 210 controls) were selected from approximately 30 primary care settings and 12 hospitals in 8 Spanish regions. Subjects were smokers or former smokers (> 10 pack-years) aged 35-50 years. Diagnosis of COPD was based on a post-bronchodilator result of FEV1/FVC < 70%.The main study variables were: questionnaires on health, symptoms, exacerbations and daily physical activity, lung function tests, blood and sputum samples, and low-dose computed tomography. In the statistical analysis, COPD patient characteristics will be described and compared with control subjects using a logistic regression analysis.  相似文献   
9.
林娟 《北方药学》2020,(2):30-31
目的:探讨美托洛尔(β1受体阻滞剂)用于老年COPD合并冠心病史治疗的临床疗效。方法:选取2018年6月—2019年6月在我院接受治疗的60岁以上(包括60岁)COPD合并冠心病史老年患者,分为对照组与观察组。对照组给予接受布地奈德福莫特罗粉吸入剂治疗,观察组在使用布地奈德福莫特罗粉吸入剂治疗的基础上口服琥珀酸美托洛尔缓释片治疗,观察对比两组治疗效果。结果:观察组临床治疗效果优于对照组,观察组住院时长以及并发症的发生率低于对照组(P<0.05),差异具有统计学意义。结论:老年COPD合并冠心病史接受美托洛尔治疗,可有效缩短住院时长、用药效果明显、有效提升用药安全性,值得临床推广。  相似文献   
10.
Between the 1930s and 1960s Puerto Rico was transformed from a marginal United States territory into an industrialised ‘showcase of development’. This article investigates the organisation of milk station programmes on the island during this crucial period and how these reflected the circulation of child welfare knowledge, nutrition expertise and public health practices. During the Depression, these perspectives fostered a recast of the eugenic regeneration ideologies motivating medical assessments of and sanitary interventions with Puerto Rico’s rural poor since the nineteenth century. Innovations in nutrition knowledge and an emerging rural hygiene movement highlighted the negative health effects of the island’s monocrops economy. In this context, the nourishment of children’s bodies assumed symbolic and instrumental significance for the reconfiguration of colonial and developmental models promoted by the new Popular Democratic Party (PPD). The experience of public health professionals in relief work during the 1930s contributed to the articulation of food and nutrition as key elements of this party’s populist discourse. Programmes like milk stations became part of strategies to rear and manage the labour force needed in the industrial development model promoted by the PPD. From the perspective of poor Puerto Ricans, however, they were part of the materialisation of its promise of social justice for the poorer classes.  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