首页 | 官方网站   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   16897篇
  免费   1399篇
  国内免费   47篇
医药卫生   18343篇
  2021年   304篇
  2020年   177篇
  2019年   319篇
  2018年   303篇
  2017年   237篇
  2016年   252篇
  2015年   295篇
  2014年   430篇
  2013年   597篇
  2012年   881篇
  2011年   922篇
  2010年   486篇
  2009年   465篇
  2008年   752篇
  2007年   841篇
  2006年   803篇
  2005年   784篇
  2004年   804篇
  2003年   729篇
  2002年   721篇
  2001年   479篇
  2000年   407篇
  1999年   427篇
  1998年   171篇
  1997年   141篇
  1996年   142篇
  1995年   116篇
  1994年   135篇
  1993年   112篇
  1992年   340篇
  1991年   314篇
  1990年   316篇
  1989年   306篇
  1988年   246篇
  1987年   261篇
  1986年   256篇
  1985年   261篇
  1984年   201篇
  1983年   155篇
  1982年   100篇
  1979年   214篇
  1978年   148篇
  1977年   142篇
  1976年   114篇
  1975年   146篇
  1974年   166篇
  1973年   142篇
  1972年   154篇
  1971年   118篇
  1970年   115篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis.  相似文献   
72.
The effects of region of interest (ROI) selection and correction for Compton-scattered photons using a buildup factor on radionuclide left ventricular volumes calculated by the Links method were compared in 19 humans with contrast ventriculography and in phantoms. Three different methods of ROI selection were compared: a manual ROI, a second derivative ROI and a 50% count-threshold ROI. In phantoms without Compton scatter correction, volumes were overestimated by 30% (manual ROI), 20% (derivative ROI) and 1% (count threshold ROI). In subjects, results without Compton scatter correction were similar with overestimates of 50% (manual ROI) and 20% (derivative ROI) and an underestimate by 3% (count threshold method). Correction for Compton-scattered photons with the use of a phantom-derived buildup factor resulted in improved accuracy for the manual ROI (+15%) and the derivative ROI (0%). A 50% count threshold ROI following interpolative background subtraction allows the accurate calculation of cardiac volumes without the need for scatter correction, while a second derivative ROI method requires a correction for Compton scatter with the use of a buildup factor.  相似文献   
73.
Compression plating for child and adolescent femur fractures.   总被引:3,自引:0,他引:3  
Twenty-five children ranging in age from 6-16 years underwent AO compression plate fixation for treatment of a femur fracture. Generally, the most common reason for plate fixation was to simplify nursing care and rehabilitation of children with an associated severe head injury or polytrauma. Twenty-three fractures healed in 11 weeks on the average, most by periosteal bone formation. Leg length discrepancy was not a clinical problem. Nursing care and polytrauma rehabilitation were simplified in all children. We believe that plate fixation is a reasonable treatment option for femoral fracture care in children aged less than 11 years with severe head injury or associated polytrauma.  相似文献   
74.
J H Levy  M S Texidor 《Pain》1988,33(1):79-80
Fifty patients with a presumptive diagnosis of acute appendicitis based on usual Western medicine criteria (e.g., McBurney point tenderness, increase WBC, history of nausea, etc.) were examined prospectively for tenderness of the Lanwei acupoint, just prior to the administration of general anesthesia, to evaluate this well known 'Appendix' point as a useful aid to diagnosing appendicitis. The presence or absence of tenderness was statistically not a good indicator of appendicitis.  相似文献   
75.
One of the most exciting developments in pediatric dermatology has been the use of the flashlamp-pumped, 585-nm, pulsed dye laser for treatment of vascular birthmarks. In many cases the results are miraculous. The increase in self-esteem and happiness of many children and adolescents has been overwhelming; for some, depression has been lifted, stuttering has ceased, social involvement has increased, and antidepressants have been discontinued. There are many success stories to tell.
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser.  相似文献   
76.
Non-digestible oligosaccharides — potential anticancer agents?   总被引:1,自引:0,他引:1  
  相似文献   
77.
78.
Arthroscopic assisted rotator cuff repair: preliminary results   总被引:2,自引:0,他引:2  
Arthroscopic assisted rotator cuff repair is a method of performing an arthroscopic subacromial decompression with repair of the rotator cuff through a limited deltoid splitting approach. We evaluated 25 patients with a minimum of 1 year follow-up. Based on the UCLA shoulder rating, 80% of the patients were rated as excellent or good. There was significant improvement in pain, function, motion, and strength. Ninety-six percent of the patients were satisfied with the procedure. Of the patients with small or moderate size tears, 100% received a satisfactory rating. Arthroscopic assisted rotator cuff repair is presented as an attractive alternative in treating symptomatic patients with complete tears of the rotator cuff.  相似文献   
79.
80.
We have examined 6 construction workers who developed chronic skin diseases on their hands over a period of 15 years (1970–1985). 4 developed a Trichophyton rubrum infection, and the other 2 an irritant contact dermatitis. All of them carried out jobs which caused traumatization of the skin, due to the presence of ethylene glycol and mineral oils during operation of pneumatic hammers in winter. They also suffered other types of skin trauma during their work. Construction workers may be at risk of developing an occupational skin disease involving fungal infection.  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-23

京公网安备 11010802026262号