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   765篇
  免费   43篇
  国内免费   6篇
耳鼻咽喉   3篇
儿科学   32篇
妇产科学   17篇
基础医学   92篇
口腔科学   25篇
临床医学   42篇
内科学   132篇
皮肤病学   23篇
神经病学   29篇
特种医学   20篇
外科学   161篇
综合类   24篇
预防医学   46篇
眼科学   19篇
药学   48篇
中国医学   6篇
肿瘤学   95篇
  2022年   10篇
  2021年   17篇
  2020年   5篇
  2019年   24篇
  2018年   24篇
  2017年   13篇
  2016年   19篇
  2015年   22篇
  2014年   51篇
  2013年   38篇
  2012年   78篇
  2011年   72篇
  2010年   42篇
  2009年   23篇
  2008年   35篇
  2007年   41篇
  2006年   35篇
  2005年   36篇
  2004年   31篇
  2003年   25篇
  2002年   20篇
  2001年   17篇
  2000年   7篇
  1999年   13篇
  1997年   5篇
  1995年   3篇
  1994年   2篇
  1993年   3篇
  1992年   4篇
  1991年   6篇
  1990年   4篇
  1988年   2篇
  1987年   2篇
  1986年   7篇
  1985年   4篇
  1984年   3篇
  1983年   13篇
  1982年   3篇
  1981年   3篇
  1980年   2篇
  1979年   5篇
  1978年   3篇
  1977年   4篇
  1976年   3篇
  1975年   5篇
  1974年   6篇
  1973年   2篇
  1972年   4篇
  1971年   3篇
  1970年   3篇
排序方式: 共有814条查询结果,搜索用时 0 毫秒
81.
82.
83.
We present a previously-healthy 12-year old girl from a rural community and who was admitted to a district general hospital in Malaysia with coagulopathy and septic shock. Despite receiving intensive care, she succumbed to her illness. Blood cultures grew Burkholderia pseudomallei. Melioidosis is an unusual cause of paediatric Gram-negative sepsis among children in Malaysia.  相似文献   
84.
85.

Summary

The goal in this study was to examine the hormonal and dietary predictors of true fractional Ca absorption (TFCA) in adult women and to determine whether TFCA differs due to body weight. Results showed that TFCA is higher in obese individuals and dietary fat, estradiol, and 1,25-dihydroxy vitamin D are the most significant positive predictors of TFCA in adult women.

Introduction

Calcium absorption is an important determinant of calcium balance and is influenced by several factors. Previous studies have identified that age, intake of protein, fat and fiber, and hormones such as 1, 25-dihyroxyvitamin D (1,25(OH)2D3) influence absorption. The determinants of TFCA using the double isotope method, the gold standard estimate of absorption, have not been examined previously in adult women nor has the role of obesity been addressed.

Methods

In this study, we examined the hormonal and dietary predictors of TFCA in adult women with a wide range of age, body weights, and nutrient intake. TFCA was measured using dual stable isotope (42Ca and 43Ca) technique. Serum was analyzed for bone-regulating hormones, and dietary information was obtained through food records. The independent dietary factors and hormonal predictors (25-hydroxyvitamin D, 1,25(OH)2D3, parathyroid hormone, and estradiol) of TFCA were analyzed using multiple regression analysis.

Results

Two hundred twenty-nine women aged 54?±?11?years old (24–75?years) and with BMI of 31?±?7.0?kg/m2 were eligible and were categorized into tertiles of body mass index (BMI) into leaner, overweight, and obese. In the entire group of women, total fat intake, estradiol, and 1,25(OH)2D3 are significant positive predictors (p?<?0.05). As expected, age is a significant negative predictor of TFCA (R 2?=?26%). TFCA is higher in obese women compared to non-obese women (p?<?0.05).

Conclusion

Together, these data show that dietary fat is the most significant positive predictor of TFCA which may have implications for dietary intake for non-obese individuals who are more likely to have lower and potentially compromised Ca absorption.  相似文献   
86.
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Adverse outcomes after radical prostatectomy are more often recorded in the elderly. In the USA, elderly patients undergoing radical prostatectomy are treated at institutions where suboptimal outcomes are recorded.

OBJECTIVE

  • ? To assess the rate of adverse outcomes after open radical prostatectomy (ORP) in the elderly and to examine the effect of annual hospital caseload (AHC) and academic institutional status on adverse outcomes in these of patients.

PATIENTS AND METHODS

  • ? Within the Health Care Utilization Project Nationwide Inpatient Sample, we focused on ORPs performed between 1998 and 2007. Subsequently, we restricted to patients aged ≥75 years.
  • ? In both datasets, we examined transfusion rates, intra‐operative and postoperative complication rates, and in‐hospital mortality rates.
  • ? Stratification was performed according to AHC tertiles and academic status.
  • ? Multivariable logistic regression analyses were fitted.

RESULTS

  • ? Of 115 554 ORP patients, 2109 (1.8%) were aged ≥75 years.
  • ? In multivariable analyses performed in the entire cohort, elderly age increased homologous blood transfusion rates (P < 0.001), intra‐operative (P= 0.001) and postoperative (P < 0.001) complication rates, and the mortality rate (P= 0.007).
  • ? Most elderly were treated at low or intermediate AHC (68.5%) and non‐academic centres (56.2%).
  • ? Within the elderly cohort, intra‐operative (2.9%) and postoperative (22.2%) complications tended to be highest at low AHC institutions compared to institutions of intermediate (2.7% and 17.4%) and high AHC (1.7% and 14.5%). Similarly, intra‐operative (2.7% vs 2.1%) and postoperative complications (19.1% vs 13.9%) tended to be higher at non‐academic than academic centres.
  • ? In multivariable analyses performed in the elderly subgroup, low AHC predicted higher intra‐operative complications and higher homologous transfusions, whereas non‐academic status predicted higher postoperative complications.

CONCLUSIONS

  • ? Adverse outcomes are more often recorded in the elderly.
  • ? Most elderly are treated at institutions where suboptimal outcomes are recorded.
  相似文献   
87.
The troubled life and death of William Thomas Green Morton has been described in several texts. His first public demonstration of ether anesthesia was the highpoint of a life that was less than successful in many of his endeavors. Close examination of this life reveals a pattern of behavior that progresses from narcissistic traits to narcissistic personality pathology. This retrospective psychiatric analysis of Morton's life was undertaken to theorize as to why Morton, after having successfully demonstrated ether anesthesia, did not continue to develop anesthesia as a clinical specialty. Biographies about Morton were used to explore details of his life. The Diagnostic and Statistical Manual of Mental Disorders classification of narcissistic personality disorder was used to analyze his life. We conclude that Morton progressed from displaying narcissistic personality trait to disorder over his lifetime.  相似文献   
88.
Rupture of the sinus of valsalva into the pulmonary artery   总被引:2,自引:0,他引:2  
Congenital aneurysms of the sinus of Valsalva are rare lesions that can rupture into any cardiac chamber, due to the central position of the aortic root. Rupture into the pulmonary artery, however, is very rare. We encountered an 18-year-old girl with rupture of the right coronary sinus into the pulmonary artery. During surgical correction, the girl was also found to have a small outlet ventricular septal defect, which was obscured by multiple hypertrophied septal trabeculae in the right ventricular outflow tract.  相似文献   
89.
90.

INTRODUCTION

A total of 17 cases of penetrating neck injury were managed by the otolaryngology team at King’s College Hospital over a 3-year period in the 1980s. In April 2010 King’s College Hospital became the major trauma centre for South East London. This prospective cohort study compares the incidence, changing demographic features and treatment outcomes of penetrating neck trauma in South East London over the previous 23 years.

METHODS

Data were collected over a 12-month period (April 2010 to March 2011) and a selective management protocol was introduced to standardise initial investigations and further treatment.

RESULTS

The past 23 years have seen a 550% increase in the incidence of penetrating neck injuries in South East London, with a marked increase in gun crime. Only 38% of cases underwent negative neck exploration in 2011 compared with 65% in 1987. Selective conservative management based on the absence of haemodynamic instability or radiological findings reduces length of hospital stay, lightens surgical workload and cuts costs without affecting morbidity or mortality.

CONCLUSIONS

The increased incidence of penetrating neck injury is a reflection of more interpersonal violence rather than a consequence of the larger South East London trauma centre catchment area. Tackling this problem requires focus on wider issues of community prevention. Sharing of data between the four London trauma centres and the police is needed to help prevent interpersonal violence and develop a universal treatment algorithm for other institutions to follow.  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