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   3085篇
  免费   175篇
  国内免费   23篇
耳鼻咽喉   47篇
儿科学   212篇
妇产科学   168篇
基础医学   271篇
口腔科学   93篇
临床医学   305篇
内科学   643篇
皮肤病学   97篇
神经病学   203篇
特种医学   105篇
外科学   575篇
综合类   54篇
一般理论   1篇
预防医学   99篇
眼科学   111篇
药学   155篇
  1篇
中国医学   1篇
肿瘤学   142篇
  2024年   1篇
  2023年   38篇
  2022年   32篇
  2021年   100篇
  2020年   56篇
  2019年   79篇
  2018年   131篇
  2017年   87篇
  2016年   127篇
  2015年   132篇
  2014年   170篇
  2013年   230篇
  2012年   233篇
  2011年   244篇
  2010年   131篇
  2009年   113篇
  2008年   229篇
  2007年   215篇
  2006年   187篇
  2005年   222篇
  2004年   185篇
  2003年   118篇
  2002年   127篇
  2001年   21篇
  2000年   13篇
  1999年   23篇
  1998年   9篇
  1997年   9篇
  1996年   4篇
  1995年   3篇
  1994年   3篇
  1993年   3篇
  1992年   1篇
  1991年   2篇
  1990年   2篇
  1989年   2篇
  1981年   1篇
排序方式: 共有3283条查询结果,搜索用时 421 毫秒
141.
A 47‐year‐old male presented to our clinic with complaints of mass in both breasts. In the patient's history, he had undergone low anterior resection for rectum mucinous adenocarcinoma 2 years ago. The masses in both breasts of the patient were excised. Mucinous adenocarcinoma metastases were reported in the pathologic evaluation of the masses. Metastasis should be considered in patients with bilateral breast mass and previously diagnosed cancer even if the patient is male.  相似文献   
142.
Baboon syndrome is a special form of systemic contact dermatitis to systemic or local administration of contact allergens. Baboon syndrome without known previous cutaneous sensitisation was also described as drug-related baboon syndrome or symmetrical drug-related intertriginous and flexural exanthema (SDRIFE). The major drugs causing SDRIFE was beta-lactam antibiotic such as amoxicillin and ampicillin. We report a case of 16-year-old woman who developed pruritic eruptions after oral metronidazole treatment for diarrhea. She was diagnosed SDRIFE according to her clinical and histopathological findings. To our knowledge, our patient is the first case who developed SDRIFE due to metronidazole in the literature.  相似文献   
143.
144.
Journal of Interventional Cardiac Electrophysiology - Aortic cusps might be the source of supraventricular or ventricular arrhythmias. For many years, aortic cusp ablation has been widely used to...  相似文献   
145.
The study was conducted to determine the validity and reliability of the tool used to assess nurses’ attitudes towards futility, and to explore intensive-care nurses’ attitudes towards futility. Principal components analysis revealed that 18item scale was made up of four subdimensions that assess Identifying(beliefs), Decision-Making, Ethical Principles and Law, and Dilemma and Responsibilities related to futile treatments. The internal consistency of the scale was in the acceptable range, with a total Cronbach’s alpha value of 0.72. Overall the results of study suggest that scale can be used as a valid and reliable assessment tool to assess nurses’ attitudes towards futility.  相似文献   
146.
147.

Aim

Over the past 2 decades, transcatheter occlusion of patent ductus arteriosus (PDA) with coils and the duct occluders evolved to be the procedure of choice. A new device, the Occlutech PDA® occluder (ODO) device has been designed. Herein, we aimed to evaluate the characteristics and short‐term results of patients who underwent transcatheter closure of PDA using the ODO.

Methods

We reviewed the clinical records of 60 patients from different centers in Turkey between December 2013 and January 2016. The medical records were reviewed for demographic characteristics and echocardiographic findings. Device size was selected on the narrowest diameter of PDA.

Results

The median patient age was 2.5 years (6 months–35 years), and median PDA diameter was 2.5 mm (1.2–11 mm). Fifty‐eight of 60 patients (96.6%) had successful ODO implantation. The occlusion rates were 37/58 (63.7%) at the end of the procedure, 51/58 (87.9%) at 24–48 hours post‐procedure, and 57/58 (98.2%) on echocardiography at a median follow‐up of 7.6 months.

Conclusion

Our results indicate that transcatheter closure of PDA using the ODO is effective. Larger studies and longer follow‐up are required to assess whether its shape and longer length make it superior to other duct occluders in large, tubular, or window‐type ducts. (J Interven Cardiol 2016;29:325–331)
  相似文献   
148.
Sustainable development (SD) as popularized by the Brundtland Commission and politically enshrined in the Sustainable Development Goals has been the explicit focus of sustainability science. While there is broad agreement that the trend of human well-being (W) over time should serve as a sustainability criterion, the literature so far has mostly addressed this in terms of its determinants rather than focusing on W itself. There is broad agreement that an indicator for W should have multiple constituents, clearly going beyond gross domestic product. Here, we propose a tailor-made indicator to serve precisely this purpose following a set of specified desiderata, including its applicability to flexibly defined subnational populations by gender, place of residence, ethnicity, and other relevant characteristics. The indicator, years of good life (YoGL), reflects the evident fact that in order to be able to enjoy any quality of life, one has to be alive and thus is primarily based on life expectancy. However, since mere survival is not considered good enough, life years are counted conditional on meeting minimum standards in two dimensions: the objective dimension of capable longevity (consisting of being out of absolute poverty and enjoying minimal levels of physical and cognitive health) and the subjective dimension of overall life satisfaction. We illustrate the calculation of this indicator for countries and subpopulations at different stages of development and with different degrees of data availability.

Sustainability science refers to the most comprehensive scholarly effort to understand the interactions between natural and social systems in order to assess whether certain developmental pathways can be considered sustainable. This should also include the possible negative effects of environmental changes, such as climate change and biodiversity loss, on future human well-being. In this paper, we propose a tailor-made indicator to assess long-term human well-being as the ultimate end of sustainable development. This indicator, called “years of good life” (YoGL), is designed in such a way that it can be both empirically measured—which is the focus of this paper—and modeled in its long-term future trends—which will be the focus of future work.When assessing changes over time in the well-being of certain human populations (or subpopulations, as defined, e.g., by gender, ethnicity, urban/rural place of residence, or other social groupings), one can focus on the determinants or the constituents of well-being. In sustainability science, thus far, empirical and theoretical research has placed more emphasis on studying the determinants, including environmental services (1), whereas specifying its constituents has received less systematic attention, often leaving us with nothing but the unspecific notion of “utility.” The focus on determinants has led to the concept of “inclusive wealth” (IW) which can be used to assess whether a society is on a sustainable development trajectory in terms of the productive base necessary to maintain a high standard of living in the future (2). However, empirically measuring the values and relative effects of the different capitals determining human well-being remains extremely challenging and “no current attempt to date can be said to be fully inclusive” (3).The idea behind YoGL, on the other hand, is to study sustainability by focusing explicitly on the constituents of well-being and its change over time. In doing so, YoGL avoids several of the pitfalls by which the IW approach is plagued (3, 4). For example, rather than making contestable quantitative assessments of the relative contributions of the different determinants of well-being, the demographic approach underlying YoGL provides numerical values of human well-being directly, expressed as the average number of years of good life a person can expect to live as part of a given subpopulation under the conditions of a specified point in time. Based on the assumed universal nature of its unit of measurement—YoGL lived today in one specific population has the same meaning as YoGL lived in the future or in another population—the indicator has a time-independent meaning. This also avoids the pitfalls of specifying a rate at which to discount future well-being, which have become apparent at least since the debates around the Stern report (5). YoGL allows us to directly compare human well-being across different subpopulations and generations. Moreover, while all estimates of the different determinants of future human well-being are highly sensitive to population growth, as a measure referring to per-person well-being the derivation of YoGL is not directly affected by assumptions about the future trajectory of population size. Finally, as stressed by Dasgupta (6), the nature of determinants can change over time and across places depending on different commodities and technological regimes, whereas the constituents of well-being—as used in YoGL—are arguably shared across space and time.In the following, we will first present the proposed design of the indicator. We will then provide a step-by-step user’s guide for empirically deriving YoGL based on the most appropriate available data source, before offering examples of how it can be calculated based on auxiliary information on populations for which the necessary data are not yet fully available. We will close with a discussion and brief outlook as to what is still needed to use this indicator for the assessment of sustainability.  相似文献   
149.
150.
GOALS To investigate the relationships between gastric emptying and autonomic dysfunction in hepatic cirrhosis and to assess the effects of cisapride on gastric emptying in cirrhotic patients.STUDY Twenty-four cirrhotic patients (8 patients in each Child-Pugh classification) and 25 healthy controls were enrolled. All the patients had viral (B or C) hepatitis. Patients with DM, alcoholic cirrhosis, active peptic ulcer, gastric malignancy and pyloric obstruction were excluded by esophagogastroduodenoscopy. Parasympathetic and sympathetic functions were assessed by the criteria set forth by Ewing and Clark. Drugs affecting GI motility and smoking were discontinued 48 hours and 12 hours prior to the study respectively. A solid-phase of gastric emptying study was conducted by scintigraphic method for the calculation of gastric half-emptying time (GET1/2). RESULTS The study revealed that 9 patients with Child-Pugh B and C cirrhosis had autonomic neuropathy and none of Child-Pugh A cirrhosis had autonomic neuropathy. Prolonged GET1/2 was noted in cirrhotics compared with the control group (p < 0.05). However, there was significant difference between 9 patients (Child B-C) with autonomic neuropathy compared with patients 15 patients without autonomic neuropathy. Again there was a significant difference in GET1/2 between Child A cirrhotic and Child B-C cirrhotic whether they had autonomic neuropathy or not. Cisapride decreased GET1/2 significantly in cirrhotic patients (Child B-C cirrhotic). Clearly, patients with autonomic neuropathy in Child B-C cirrhosis had significantly reduced GET1/2 after cisapride administration. Even though cisapride decreased GET1/2 in patients with Child B-C cirrhosis without autonomic neuropathy, this was not significant. CONCLUSION Autonomic neuropathy in advanced cirrhosis from viral hepatitis may cause prolonged gastric emptying. Cisapride can shorten gastric emptying time in such patients.  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