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   2835篇
  免费   192篇
  国内免费   4篇
耳鼻咽喉   18篇
儿科学   153篇
妇产科学   71篇
基础医学   375篇
口腔科学   441篇
临床医学   140篇
内科学   434篇
皮肤病学   127篇
神经病学   182篇
特种医学   67篇
外科学   325篇
综合类   187篇
一般理论   1篇
预防医学   144篇
眼科学   120篇
药学   118篇
中国医学   8篇
肿瘤学   120篇
  2023年   31篇
  2022年   43篇
  2021年   134篇
  2020年   77篇
  2019年   73篇
  2018年   101篇
  2017年   69篇
  2016年   64篇
  2015年   77篇
  2014年   120篇
  2013年   113篇
  2012年   168篇
  2011年   193篇
  2010年   104篇
  2009年   89篇
  2008年   140篇
  2007年   163篇
  2006年   160篇
  2005年   129篇
  2004年   130篇
  2003年   107篇
  2002年   105篇
  2001年   57篇
  2000年   66篇
  1999年   57篇
  1998年   22篇
  1997年   19篇
  1996年   22篇
  1995年   12篇
  1994年   14篇
  1993年   11篇
  1992年   35篇
  1991年   38篇
  1990年   34篇
  1989年   32篇
  1988年   20篇
  1987年   23篇
  1986年   20篇
  1985年   22篇
  1984年   15篇
  1983年   11篇
  1982年   19篇
  1979年   9篇
  1977年   8篇
  1976年   5篇
  1975年   6篇
  1974年   10篇
  1972年   11篇
  1971年   16篇
  1970年   8篇
排序方式: 共有3031条查询结果,搜索用时 15 毫秒
61.

INTRODUCTION

Microalbuminuria is an early sign of kidney damage. The prevalence of microalbuminuria in Singapore has been reported to be 36.0%–48.5%. However, the prevalence of microalbuminuria reported in these studies was determined with one urine sample using a qualitative urine test. The aim of this study was to determine the prevalence of micro- and macroalbuminuria using a more stringent criterion of two positive quantitative urine albumin-creatinine ratio (ACR) tests.

METHODS

We conducted a cross-sectional study of patients with type 2 diabetes mellitus (T2DM) who were followed up at a primary care clinic in Singapore. Patients were diagnosed to have albuminuria if they had two positive ACR tests within a seven-month period.

RESULTS

A total of 786 patients with T2DM met the study’s inclusion criteria. 55.7% were already on an angiotensin-converting enzyme inhibitor (ACEI) and/or angiotensin receptor blocker (ARB). The prevalence rates of micro- and macroalbuminuria were 14.2% and 5.7%, respectively. Patients with albuminuria were more likely to have hypertension (odds ratio [OR] 3.47, 95% confidence interval [CI] 1.55–7.80). Diabetics with poorer diabetic control (OR 1.88, 95% CI 1.26–2.79), and higher systolic (OR 1.69, 95% CI 1.14–2.49) and diastolic (OR 1.96, 95% CI, 1.20 to 3.22) blood pressures were more likely to have albuminuria.

CONCLUSION

In the present study, the prevalence of microalbuminuria is significantly lower than that previously reported in Singapore. The presence of hypertension, poor diabetic control and suboptimal blood pressure control are possible risk factors for albuminuria in patients with T2DM.  相似文献   
62.
INTRODUCTIONNear-peer teaching is gaining popularity as a teaching modality, as it improves the learner’s understanding, is targeted at an appropriate level and promotes familiarisation. This study was initiated to evaluate the effectiveness of incorporating near-peer instruction into simulation-based training within a junior residency programme.METHODS42 first-year residents from an internal medicine junior residency programme were recruited. Participants underwent a simulation-based training programme conducted over five weeks. Each week involved either an emergency or acute clinical scenario. A structured questionnaire was administered prior to and after the course to compare participants’ perceived knowledge, experience and confidence in managing the clinical scenarios.RESULTSIn our study, 83% of participants agreed/strongly agreed that the scenarios were realistic. There were improvements in perceived knowledge, experience and confidence after the course. The greatest improvement was seen for experience (post-simulation: median 7.00 [interquartile range (IQR) 6.00‒8.00] vs. pre-simulation: median 5.00 [IQR 3.00–6.25]). 65% of participants were keen to help with future training.CONCLUSIONNear-peer simulation training was found to be a viable and valuable method of instruction for first-year residents for increasing experience, instilling confidence and improving perceived knowledge. Integration of such programmes within medical education curricula shows good promise of continuity, with many first-year residents inspired to organise subsequent sessions.  相似文献   
63.
64.

Introduction

Minimally-invasive options for the management of choledocholithiasis in patients undergoing laparoscopic cholecystectomy include laparoscopic and endoscopic approaches. This study reviews the effectiveness of both approaches in an emergency setting.

Methods

A retrospective chart review was performed for a cohort of patients who underwent laparoscopic cholecystectomy. Outcomes assessed were duct clearance, the number of procedures performed (NPP), length of stay (LOS) and complication rate.

Results

A total of 182 patients who underwent emergency laparoscopic cholecystectomies received intervention for choledocholithiasis. The duct clearance rate was lower in the laparoscopic group, 63% versus 86% (P = 0.001). However, the median NPP was also lesser in the laparoscopic group, 1 (interquartile range (IQR) 1–2) versus 2 (IQR 2–2) (P < 0.001), as was the median LOS, 5 days (IQR 3–8) versus 7 days (IQR 6–10) (P = 0.009). Forty-eight laparoscopic endobiliary stents were attempted; stent deployment was successful in 37 patients. A larger proportion of patients with laparoscopic endobiliary stents had duct clearance by endoscopic retrograde cholangiopancreatography (ERCP) compared with those without, although this was not statistically significant (P = 0.208).

Conclusion

Laparoscopic clearance is not as effective as post-operative ERCP in an emergency cohort, but is associated with fewer procedures required and a shorter inpatient stay. Thus, laparoscopic clearance may still be an attractive option for surgeons especially where conditions are favourable during an emergency laparoscopic cholecystectomy.  相似文献   
65.
66.
[目的]分析茜草及茜草炭的红外原谱及二阶导数谱,提取红外谱图特征。[方法]利用现代红外光谱技术,对茜草及茜草炭进行分析。[结果]茜草炒炭前后红外原谱、二阶导数谱有明显的变化,表明红外技术用于中药材及其炮制品的鉴别是可行的。[结论]红外光谱法样品的制备较简单,仪器设备普及性较强,在中药材饮片的快速鉴别中占据一定的优势。  相似文献   
67.

Aims/hypothesis

A 10 s sprint has been reported to provide a means to prevent acute post-exercise hypoglycaemia in young adults with type 1 diabetes because of its glycaemia-raising effect, but it is unclear whether this effect is impaired by antecedent hypoglycaemia. The purpose of this study was to investigate whether antecedent hypoglycaemia impairs the glycaemia-raising effect of a 10 s sprint in individuals with type 1 diabetes.

Methods

Eight individuals underwent a hyperinsulinaemic–hypoglycaemic or hyperinsulinaemic–euglycaemic clamp on two separate mornings. Thereafter, the participants underwent a basal insulin–euglycaemic clamp before performing a 10 s sprint on a cycle ergometer. The levels of blood glucose and glucoregulatory hormones and rates of glucose appearance (Ra) and disappearance (Rd) were compared between conditions.

Results

During the morning clamps, blood glucose levels were significantly different between conditions of hypoglycaemia (2.8?±?0.1 mmol/l) and euglycaemia (5.4?±?0.2 mmol/l; p?<?0.001). Mean glycaemia prior to sprinting was similar (5.6?±?0.4 and 5.5?±?0.3 mmol/l for hypoglycaemic and euglycaemic conditions, respectively; p?=?0.83). In response to the afternoon sprint, the pattern of increase in blood glucose levels did not differ between conditions, reaching similar maximal levels 45 min after exercise (6.5?±?0.4 and 6.6?±?0.3 mmol/l, respectively; p?=?0.43). The early post-exercise patterns in glucose Ra and Rd and increases in plasma adrenaline (epinephrine), growth hormone and cortisol levels did not differ between conditions.

Conclusions/interpretation

Hypoglycaemia in the morning does not diminish the glycaemia-raising effect of an afternoon 10 s sprint in young adults with type 1 diabetes, suggesting that sprinting is a useful strategy for opposing hypoglycaemia, regardless of prior hypoglycaemia.  相似文献   
68.
Cardiovascular Disease (CVD) is the leading cause of deaths worldwide, contributing to about 30% of all deaths. Half of the cases of CVD are estimated in Asia, the world's most populous continent. Hypertension, a major modifiable risk factor for CVD, results in more deaths than any other CV risk factors in the Asian regions. The total number of patients with hypertension is likely to grow as the population ages. The proportion of the elderly population aged 65 years or more in Asia is expected to increase from 7.4% in 2015 to 10.9% in 2030. It is important to note that more than half (54%) of the world's population live in Asia. Aside of being the biggest single risk factor for global deaths, hypertension is also an important precursor and most common risk factor of heart failure (HF). An increase in HF prevalence is clearly related to the rapid epidemiological transition caused by changes in lifestyle in Asian countries. However, the availability of data on HF burden and health care delivery is limited in Asia compared with Europe and North America. This reality has driven the working group of Asian experts for example the HOPE Asia Network to concentrate on hypertension as risk factors for CVD, with the mission to improve the management of hypertension resulting in organ protection toward a goal of achieving “ZERO” CV event in Asia. This paper aims to give an overview regarding the heart problems caused by hypertension in Asia, focus on HF.  相似文献   
69.
Ambulatory blood pressure monitoring (ABPM) can measure 24‐hour blood pressure (BP), including nocturnal BP and diurnal variations. This feature of ABPM could be of value in Asian populations for preventing cardiovascular events. However, no study has yet investigated regarding the use of ABPM in actual clinical settings in Asian countries/regions. In this study, 11 experts from 11 countries/regions were asked to answer questionnaires regarding the use of ABPM. We found that its use was very limited in primary care settings and almost exclusively available in referral settings. The indications of ABPM in actual clinical settings were largely similar to those of home BP monitoring (HBPM), that is, diagnosis of white‐coat or masked hypertension and more accurate BP measurement for borderline clinic BP. Other interesting indications, such as nighttime BP patterns, including non‐dipper BP, morning BP surge, and BP variability, were hardly adopted in daily clinical practice. The use of ABPM as treatment guidance for detecting treated but uncontrolled hypertension in the Asian countries/regions didn't seem to be common. The barrier to the use of ABPM was primarily its availability; in referral centers, patient reluctance owing to discomfort or sleep disturbance was the most frequent barrier. ABPM use was significantly more economical when it was reimbursed by public insurance. To facilitate ABPM use, more simplified indications and protocols to minimize discomfort should be sought. For the time being, HBPM could be a reasonable alternative.  相似文献   
70.
The Hypertension Cardiovascular Outcome Prevention and Evidence in Asia (HOPE Asia) Network was set up to improve the management of hypertension in Asia with the ultimate goal of achieving “zero” cardiovascular events. Asia is a diverse continent, and the prevalence of hypertension has increased over the last 30 years. There are a number of Asia‐specific features of hypertension and hypertension‐related cardiovascular complications, which means that a region‐specific approach is needed. White‐coat hypertension will become more of an issue over time as Asian populations age, and masked hypertension is more prevalent in Asian than in Western countries. Identifying and treating masked hypertension is important to reduce cardiovascular risk. Abnormal patterns of blood pressure (BP) variability common in Asia include exaggerated early morning BP surge and nocturnal hypertension. These are also important cardiovascular risk factors that need to be managed. Home blood pressure monitoring (HBPM) is an important tool for detecting white‐coat and masked hypertension, and monitoring BP variability, and practices in Asia are variable. Use of HBPM is important given the Asia‐specific features of hypertension, and strategies are needed to improve and standardize HBPM usage. Development of HBPM devices capable of measuring nocturnal BP along with other information and communication technology‐based strategies are key developments in the widespread implementation of anticipation medicine strategies to detect and prevent cardiovascular events in patients with hypertension. Region‐wide differences in hypertension prevalence, control, and management practices in Asia highlight the importance of information sharing to facilitate best practices.  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