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   1637篇
  免费   68篇
  国内免费   18篇
耳鼻咽喉   26篇
儿科学   105篇
妇产科学   102篇
基础医学   124篇
口腔科学   110篇
临床医学   123篇
内科学   282篇
皮肤病学   32篇
神经病学   152篇
特种医学   29篇
外科学   321篇
综合类   25篇
预防医学   23篇
眼科学   67篇
药学   78篇
中国医学   1篇
肿瘤学   123篇
  2023年   12篇
  2022年   19篇
  2021年   29篇
  2020年   20篇
  2019年   36篇
  2018年   28篇
  2017年   22篇
  2016年   35篇
  2015年   63篇
  2014年   64篇
  2013年   96篇
  2012年   120篇
  2011年   135篇
  2010年   67篇
  2009年   46篇
  2008年   100篇
  2007年   108篇
  2006年   109篇
  2005年   120篇
  2004年   99篇
  2003年   86篇
  2002年   77篇
  2001年   33篇
  2000年   37篇
  1999年   37篇
  1998年   8篇
  1997年   14篇
  1996年   12篇
  1995年   8篇
  1994年   6篇
  1993年   9篇
  1992年   10篇
  1991年   19篇
  1990年   7篇
  1989年   6篇
  1988年   5篇
  1987年   4篇
  1986年   3篇
  1985年   2篇
  1984年   3篇
  1983年   1篇
  1982年   1篇
  1978年   1篇
  1974年   2篇
  1972年   2篇
  1970年   1篇
  1967年   1篇
排序方式: 共有1723条查询结果,搜索用时 31 毫秒
91.
92.
In this paper, research based on 51 children with a positive antiglobulin test is presented. Eighteen of the children had acute anemia and 33 had chronic anemia. Two clinical patterns were distinguished: an acute transient type and a prolonged chronic type. Corticosteroid therapy was effective in all acute cases but its results were variable in the chronic cases. The acute form was more frequent in young children, while chronic autoimmune hemolytic anemia (AIHA) occurred mainly among children at puberty. In the chronic form of the disease, it was sometimes necessary to add immunosuppressive drugs and in two cases to perform a splenectomy.  相似文献   
93.
In order to determine the prognostic significance of cell size together with expression of biphenotypic markers in childhood acute myeloblastic leukemia (AML), we evaluated the cell size of children with AML, 12 with and 21 without biphenotypic markers. The patients were followed up for at least 12 months. The cells which were stained with FITC conjugated surface marker antibodies were divided into small, middle or large cell groups according to their mean channel number of forward scatter by flow cytometry. Nine of 12 biphenotypic and 15 of 21 non-biphenotypic children either died or relapsed within the first 12 months. The percentages of the small, middle and large cells were similar in children and in deceased patients, regardless of whether or not they expressed biphenotypic markers. We believe that biphenotypic marker expression is a poor prognostic factor regardless of cell size.  相似文献   
94.
CD34/CD117 co-expression in childhood acute leukemia   总被引:3,自引:0,他引:3  
CD117 protein is expressed by the primitive CD34 positive haemopoietic stem cells and also demonstrated on the blasts of 30-100% of AML cases, but rarely on lymphoblasts. Therefore several investigators have used CD117 expression to exclude lymphoblastic origin of blasts. However, conflicting results exist in the literature. We investigated CD34 and CD117 status at initial presentation of 232 children with acute leukemia. CD34 was commonly expressed in all types of acute leukemias, whereas CD117 molecule seemed to be a more specific marker for leukemia of myeloid origin being demonstrated on > 5% of blasts in 60 out of 73 cases of AML patients, but rarely detected in ALL (9/140 patients). Moreover, co-expression of CD34/CD117 was extremely rare on lymphoblasts with only 3/140 ALL patients demonstrating > 5% co-expression of CD34 and CD117, and therefore we suggest that it should be used in the exclusion of ALL.  相似文献   
95.
The coexistence of lung cancer and glomerular lesion is not commonly reported. Malignancy-related glomerulopathy is commonly membranous glomerulonephritis. Other glomerulopathies are seldom reported. We report two cases presenting with non-small-cell lung cancer, acute renal failure and nephrotic syndrome secondary to membranoproliferative glomerulonephritis and amyloidosis.  相似文献   
96.
Intradural spinal lipomas of thoracic cord are quite rare. It is known that lipomas are hamartomas, which change their size with alterations of body fat. An 18-year-old male patient, with a thoracic intradural lipoma showing spontaneous decrease in the size of a residual lipoma and tethering of the cord 4 years after surgery, is presented in this report.  相似文献   
97.
Disorders of elbow extension occur following traumatic or neurologic injuries of the triceps muscle. Restoration of elbow extension is an integral part of the entire upper extremity surgical reconstruction to improve the following daily activities: bringing down an object from above, handwriting, using the hand in the supine position, steering a wheelchair, driving a car, and swimming. The transfer of the posterior head of the deltoid muscle to triceps (Moberg procedure) and the transfer of the biceps to triceps (Friedenberg procedure) are previously described procedures for the functional restoration of triceps function. In conditions where these procedures cannot be used, we describe a new technique for restoration of elbow extension. In 4 cases with obstetrical palsy sequela, where shoulder abduction was established with the latissimus dorsi and teres major transfer, restoration of elbow extension was planned to aid in activities performed while the hand is above the head. To achieve this goal, the brachioradialis muscle was transposed bipedically to the triceps muscle.  相似文献   
98.
BACKGROUND AND AIM OF THE STUDY: We present our experience on patients with renal artery stenosis undergoing myocardial revascularization procedures. METHODS: Eighteen patients with varying degrees of renal artery stenosis were operated for coronary artery bypass grafting between 1996 and 2003. The overall incidence was 0.15%. There were nine male and nine female patients with a mean age of 62 +/- 8.2 (40-72 years). Four had bilateral and eight had significant unilateral (>50%) renal artery stenoses. Preoperatively, three patients had renal arterial intervention (stenting), and one patient was on hemodialysis. The mean preoperative creatinine value was 2.6 +/- 2.7 mg/dL (range 0.7 to 9.3). The patients were followed medically: two patients underwent off-pump coronary bypass grafting and the others were operated on-pump. RESULTS: There was only one mortality and two patients required hemodialysis postoperatively. The postoperative mean creatinine values were 3.4 +/- 4.9 mg/dL (range 1.0 to 12.5). No electrolyte imbalances were noted except that one case revealed a transient metabolic acidosis. Five patients required inotropic support with dopamine and two needed diuretic infusions. Only five patients demonstrated a refractory hyper tensive period postoperatively. CONCLUSIONS: The concomitant correction of renal artery stenosis with CABG is usually not necessary, but the principles for renovascular diseases must be kept in mind and individually oriented strategies must be planned.  相似文献   
99.
BACKGROUND AND AIM: Apoptosis plays a crucial role in glomerulonephritis (GN) as a regulatory mechanism and is controlled by various molecules including Fas antigen, Bcl-2 and p53 oncoproteins. The aim of the present study is to evaluate the correlation between the expression of these molecules and clinical and laboratory data in different types of GN. RESULTS: The expression of Fas antigen, Bcl-2 and p53 protein in five normal human kidney specimens and 55 tissues from patients with several types of GN were examined by immunohistochemistry and correlated with clinical and laboratory findings. The number of Fas-positive intraglomerular cells was significantly increased in proliferative GN when compared with non-proliferative cases. Numbers of Bcl-2- and p53-positive cells in proliferative GN were not different from the non-proliferative cases and there was no correlation between the changes in Fas, Bcl-2 and p53 themselves. Significant correlation of expression of these molecules with clinical and laboratory findings was not found, except between p53 and blood urea nitrogen levels. CONCLUSION: Apoptosis is a complex molecular process and the results of the present study should be supported with other methods to understand whether apoptosis contributes to progression or resolution of GN. Increased glomerular expression of Fas, Bcl-2 and p53 molecules in all types of GN might contribute new therapeutic approaches by modulating the expression of these molecules.  相似文献   
100.
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