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   2212篇
  免费   139篇
  国内免费   11篇
耳鼻咽喉   5篇
儿科学   163篇
妇产科学   31篇
基础医学   296篇
口腔科学   110篇
临床医学   288篇
内科学   370篇
皮肤病学   39篇
神经病学   87篇
特种医学   303篇
外科学   181篇
综合类   43篇
预防医学   189篇
眼科学   62篇
药学   88篇
  1篇
中国医学   1篇
肿瘤学   105篇
  2022年   9篇
  2021年   26篇
  2020年   14篇
  2019年   23篇
  2018年   28篇
  2017年   22篇
  2016年   24篇
  2015年   42篇
  2014年   48篇
  2013年   38篇
  2012年   66篇
  2011年   64篇
  2010年   62篇
  2009年   67篇
  2008年   70篇
  2007年   65篇
  2006年   59篇
  2005年   48篇
  2004年   55篇
  2003年   50篇
  2002年   55篇
  2001年   46篇
  2000年   48篇
  1999年   43篇
  1998年   94篇
  1997年   90篇
  1996年   106篇
  1995年   74篇
  1994年   61篇
  1993年   59篇
  1992年   64篇
  1991年   44篇
  1990年   36篇
  1989年   63篇
  1988年   62篇
  1987年   69篇
  1986年   49篇
  1985年   61篇
  1984年   42篇
  1983年   33篇
  1982年   29篇
  1981年   24篇
  1980年   12篇
  1979年   15篇
  1978年   10篇
  1977年   14篇
  1976年   15篇
  1975年   17篇
  1974年   9篇
  1968年   8篇
排序方式: 共有2362条查询结果,搜索用时 0 毫秒
1.
2.
Others have reported that spinal cord transection non-uniformly affects the activities of the cardiac, renal and splenic nerves. We were unable to confirm this finding while recording the wide band (1-1000 Hz) discharges of these sympathetic nerves in baroreceptor-denervated, chloralose-anesthetized cats. Most of the power in nerve discharges was below 6 Hz. There was high coherence between the low frequency discharges of different nerves, and power below 15 Hz was essentially eliminated by spinal transection. Evidence is presented that the disparities between this and past studies are, in part, due to the use of a 30-Hz high-pass filter in the earlier studies.  相似文献   
3.
4.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease.  相似文献   
5.
We describe a patient with bilateral ureteral pseudodiverticulosis of 10 years’ duration before developing transitional carcinoma of the pelvis.  相似文献   
6.
Chronic low back pain: comparison of bone SPECT with radiography and CT   总被引:1,自引:0,他引:1  
Ryan  PJ; Evans  PA; Gibson  T; Fogelman  I 《Radiology》1992,182(3):849
  相似文献   
7.
To determine the clinical features, course and outcome of patients with cardiac tamponade, 57 consecutive patients with new, large pericardial effusions were prospectively studied. Twenty-five patients (44%) developed cardiac tamponade with venous hypertension and a pulsus paradoxus greater than 10 mm Hg. Electrocardiography, radiographic studies and echocardiography did not differentiate patients with and without tamponade. All 57 patients underwent thorough diagnostic evaluation followed by subxiphoid pericardial biopsy and drainage. A diagnosis was obtained in 53 patients (93%). Collagen vascular disease was significantly more frequent in the 25 patients with than in the 32 without cardiac tamponade (24 vs 3%; p less than 0.05). The frequency of malignant and uremic effusions was equal in both groups, whereas radiation-induced effusions seldom produced tamponade. At 1-year follow-up, 3 patients (12%) with tamponade had recurrent effusions, and 1 needed reoperation. This was not significantly different from the 32 patients without tamponade. Twelve-month mortality was also similar in both groups (36 vs 44%). This prospective series disclosed several unexpected findings: (1) Cardiac tamponade occurred in almost 50% of patients with new large pericardial effusions; (2) both malignancy and collagen vascular disease occurred with equal frequency as etiologies, whereas radiation-induced tamponade was unusual; (3) thorough clinical evaluation resulted in few idiopathic etiologies; and (4) subxiphoid pericardiotomy was effective for both diagnosis and therapy of tamponade.  相似文献   
8.
Incidental detection of renal mass in a transplant patient is a diagnostic challenge. These patients are at risk for the development of neoplasms and, more commonly, infection with atypical organisms. Symptomatology may be lacking in either, and both conditions may present with similar symptoms. Magnetic resonance imaging (MRI) evaluation with gadolinium DTPA is helpful in the evaluation of asymptomatic renal mass, with enhancement effectively excluding simple and hemorrhagic cysts. Because the MRI appearances of renal cell neoplasm and renal abscess overlap, both must be considered in the differential diagnosis.  相似文献   
9.
Huntington's disease (HD) is a neurodegenerative disorder associated with expansion of CAG trinucleotide repeats in the huntingtin gene. A minimum of 36 CAG repeats is usually reported in patients with clinical features of HD; 30 to 35 repeats represent an intermediate range. Here we report a 65-year-old male with autopsy-proven HD and 29 CAG repeats.  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