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   1507篇
  免费   131篇
  国内免费   22篇
耳鼻咽喉   8篇
儿科学   36篇
妇产科学   6篇
基础医学   124篇
口腔科学   21篇
临床医学   176篇
内科学   240篇
皮肤病学   6篇
神经病学   104篇
特种医学   202篇
外科学   171篇
综合类   57篇
预防医学   207篇
眼科学   18篇
药学   120篇
肿瘤学   164篇
  2022年   11篇
  2021年   21篇
  2020年   17篇
  2019年   31篇
  2018年   22篇
  2017年   17篇
  2016年   14篇
  2015年   19篇
  2014年   27篇
  2013年   40篇
  2012年   51篇
  2011年   64篇
  2010年   54篇
  2009年   49篇
  2008年   42篇
  2007年   74篇
  2006年   47篇
  2005年   78篇
  2004年   46篇
  2003年   53篇
  2002年   40篇
  2001年   60篇
  2000年   53篇
  1999年   39篇
  1998年   53篇
  1997年   56篇
  1996年   40篇
  1995年   33篇
  1994年   22篇
  1993年   20篇
  1992年   17篇
  1991年   20篇
  1990年   28篇
  1989年   27篇
  1988年   37篇
  1987年   27篇
  1986年   29篇
  1985年   30篇
  1984年   16篇
  1983年   17篇
  1982年   24篇
  1981年   11篇
  1980年   21篇
  1979年   10篇
  1978年   16篇
  1977年   16篇
  1976年   24篇
  1975年   9篇
  1969年   10篇
  1968年   11篇
排序方式: 共有1660条查询结果,搜索用时 15 毫秒
1.
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.  相似文献   
2.
Bilateral Achilles tendon rupture is an unusual injury. This rare entity usually occurs in patients on chronic steroid therapy or with underlying disease. Bilateral Achilles tendon rupture is extremely rare in a previously healthy individual. A case involving traumatic Achilles tendon rupture as a result of a sky diving accident is reported. Evaluation of patients with suspected Achilles tendon rupture is briefly reviewed.  相似文献   
3.
4.
Five members in three generations of a family were affected by an illness that had many clinical features of the hypokalemic form of periodic paralysis (HPP). The serum potassium was either moderately reduced or normal during attacks, and there was no evidence of myotonia or cold-intolerance. All of the patients improved to a variable degree with oral potassium supplements, and 3 responded favorably to triamterene. The usually beneficial drug acetazolamide, however, invariably caused weakness in these patients, an effect previously described in only one other family with HPP. In addition, amphetamine-like sympathomimetic drugs effectively aborted or prevented paralysis in several members. Muscle biopsy in two patients revealed some unusual features, and electromyography showed myopathic potentials. There was no evidence of diabetes. The urine electrolyte concentrations during glucose tolerance tests, however, were different from those previously reported in HPP. This family may represent a variant form of HPP.  相似文献   
5.
6.
7.
8.
9.
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
10.
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