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   5734篇
  免费   656篇
  国内免费   10篇
耳鼻咽喉   81篇
儿科学   164篇
妇产科学   121篇
基础医学   925篇
口腔科学   200篇
临床医学   635篇
内科学   1341篇
皮肤病学   78篇
神经病学   434篇
特种医学   232篇
外科学   686篇
综合类   98篇
一般理论   7篇
预防医学   633篇
眼科学   52篇
药学   378篇
中国医学   3篇
肿瘤学   332篇
  2023年   45篇
  2022年   39篇
  2021年   132篇
  2020年   89篇
  2019年   133篇
  2018年   138篇
  2017年   85篇
  2016年   104篇
  2015年   140篇
  2014年   182篇
  2013年   228篇
  2012年   336篇
  2011年   310篇
  2010年   189篇
  2009年   164篇
  2008年   253篇
  2007年   270篇
  2006年   231篇
  2005年   252篇
  2004年   225篇
  2003年   192篇
  2002年   215篇
  2001年   163篇
  2000年   174篇
  1999年   140篇
  1998年   68篇
  1997年   53篇
  1996年   55篇
  1995年   53篇
  1994年   41篇
  1993年   40篇
  1992年   87篇
  1991年   108篇
  1990年   106篇
  1989年   105篇
  1988年   89篇
  1987年   71篇
  1986年   92篇
  1985年   90篇
  1984年   56篇
  1983年   91篇
  1981年   54篇
  1980年   39篇
  1979年   65篇
  1978年   49篇
  1977年   41篇
  1976年   39篇
  1975年   50篇
  1973年   52篇
  1972年   45篇
排序方式: 共有6400条查询结果,搜索用时 468 毫秒
21.
22.
A case of multiple injuries including blunt rupture of the stomach is reported. It demonstrates that Candida needs to be considered as a possible cause of continued sepsis following a ruptured viscus in the presence of multiple trauma. Surgical drainage is required in this situation, in the same way that abscesses caused by more conventional organisms require aggressive surgical treatment.  相似文献   
23.
Postprandial hyperglycemia in diabetic patients can be modified by delaying the digestion and/or absorption of dietary carbohydrates. We have studied an orally active α-glucosidase inhibitor, Bay 1099, in normal volunteers to determine whether these inhibitors can decrease postprandial rises in serum glucose without causing gastrointestinal symptoms or significant fecal caloric wastage. Six subjects were given 25, 50, or 100 mg of Bay 1099 or placebo before meals for 1 week, each with a 1-week washout period. Fasting and postprandial concentrations of glucose, insulin, glucagon, enteroglucagon, and gastrointestinal inhibitory peptide (GIP) were measured after the first and last dose of Bay 1099, and the fecal excretions of protein, fat, fiber, and total calories were measured on the last three days of each diet. The passage of unabsorbed carbohydrate into the colon was determined by breath hydrogen analysis three times during each study week. Increasing doses of Bay 1099 were found to decrease the postprandial rise in serum glucose concentration, delay the time to peak insulin concentration, and decrease the output of GIP after the meal. No adaptation was apparent after 1 week of therapy. A dose of inhibitor (50 mg tid), which greatly improves postprandial glucose and hormone output in diabetes, was associated with minimal symptoms and no excess fecal caloric losses. Thus, glucosidase inhibitors such as Bay 1099 may be useful in the management of patients with carbohydrate intolerance.  相似文献   
24.
Mesenteric and retroperitoneal cysts.   总被引:10,自引:0,他引:10       下载免费PDF全文
R J Kurtz  T M Heimann  J Holt    A R Beck 《Annals of surgery》1986,203(1):109-112
Mesenteric and retroperitoneal cysts are rare intra-abdominal tumors. Ten new patients are presented as well as 152 other cases reported in the English literature. These 162 cases were then analyzed for significant trends. Patients under 10 years of age were significantly different from the older group with respect to a shorter duration of symptoms, a higher number of patients requiring an emergency operation, a lower number of recurrences and the location of the cyst. Patients with retroperitoneal cysts were more likely to have incomplete excision of the cyst and therefore had a higher incidence of recurrence. They also required marsupialization more often. Retroperitoneal cysts should be considered a different entity from mesenteric cysts even though they present clinically in a similar fashion. The outcome of surgical treatment is less satisfactory in patients with retroperitoneal cysts.  相似文献   
25.
Ear canal cholesteatoma.   总被引:25,自引:0,他引:25  
J J Holt 《The Laryngoscope》1992,102(6):608-613
Although cholesteatomas are more commonly found in the middle ear and the mastoid, the disease can occur in the external ear canal. All cases of ear canal cholesteatoma treated by the author were reviewed. There were nine ears in seven patients, who had an average age of 62 years. The lesions ranged in size from a few millimeters to extensive mastoid destruction. Smaller lesions can be managed by frequent cleaning as an office procedure. Larger lesions require surgery, either canaloplasty or mastoidectomy. The otolaryngologist should suspect this disease in the elderly. Microscopic examination of the ear with meticulous cleaning of all wax, especially in elderly patients, is most useful in detecting early disease. Frequent applications of mineral oil to the canal should be used in the management of the disease and to prevent recurrence.  相似文献   
26.
Highly complex and specialized care plans sometimes overwhelm the comprehension of patients and families. Many optimistic surrogates of critically ill patients err on the side of desiring that everything be done but with a nebulous idea of what 'everything' entails. Physicians must work closely to educate surrogates as to the benefits versus the risks of treatment. Our roundtable experts ponder the question of whether providers possess the authority to interpret unilaterally the nature of requests for everything.  相似文献   
27.
28.
29.
30.
A novel method for estimating the susceptibility of an object by using the magnetic resonance (MR) imaging field distortions in an external-reference water bath next to the object is described. The field measurement was obtained with a phase reconstruction from a gradient-echo acquisition. A field model of an arbitrary object in a static magnetic field was discretely calculated from geometry determined from the magnitude reconstruction. Least-squares estimation yields the susceptibility of the object. Required (and proven) assumptions include validity of superposition, object homogeneity, negligible higher-order field terms, field-model accuracy, geometric-model accuracy, and correlation of gradient-echo phase to field distortion. MR susceptometry estimation of phantoms yielded susceptibility estimates that correlated well with known values (r >.9975). This MR susceptometry method is a first step toward quantitation of iron levels through MR imaging phase information in patients with iron overload.  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