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   247篇
  免费   7篇
  国内免费   35篇
儿科学   12篇
基础医学   14篇
口腔科学   11篇
临床医学   46篇
内科学   46篇
皮肤病学   6篇
神经病学   4篇
特种医学   89篇
外科学   8篇
综合类   22篇
预防医学   2篇
眼科学   3篇
药学   16篇
肿瘤学   10篇
  2023年   3篇
  2021年   3篇
  2019年   1篇
  2018年   1篇
  2017年   2篇
  2015年   1篇
  2014年   2篇
  2013年   3篇
  2012年   1篇
  2011年   2篇
  2010年   3篇
  2009年   6篇
  2008年   3篇
  2007年   13篇
  2006年   5篇
  2005年   19篇
  2004年   2篇
  2002年   1篇
  2001年   4篇
  2000年   2篇
  1999年   7篇
  1998年   16篇
  1997年   18篇
  1996年   24篇
  1995年   13篇
  1994年   11篇
  1993年   24篇
  1992年   2篇
  1991年   4篇
  1990年   3篇
  1989年   10篇
  1988年   13篇
  1987年   9篇
  1986年   4篇
  1985年   5篇
  1984年   10篇
  1983年   7篇
  1982年   7篇
  1981年   6篇
  1980年   3篇
  1979年   3篇
  1978年   4篇
  1977年   3篇
  1976年   3篇
  1975年   3篇
排序方式: 共有289条查询结果,搜索用时 15 毫秒
51.
Interleukin-5 is at 5q31 and is deleted in the 5q- syndrome   总被引:3,自引:0,他引:3  
Human interleukin-5 (IL-5) is a selective eosinophilopoietic and eosinophil-activating growth hormone. By in situ hybridization this gene is mapped to chromosome 5q23.3 to 5q32. It is shown to be deleted in two patients with the 5q-syndrome and in one patient previously diagnosed with myelodysplasia whose condition had progressed to acute myeloblastic leukemia. The clustering of other genes involved in hematopoiesis (IL-3, granulocyte-macrophage colony-stimulating factor, feline sarcoma viral oncogene homolog, colony-stimulating factor 1) to the same region as IL-5 suggests a nonrandom localization and raises interesting questions concerning the evolution and regulation of these genes.  相似文献   
52.
53.
54.
55.
Respiratory function was evaluated in 11 patients with prune-belly syndrome. Nine had evidence of gas trapping and six of restrictive lung disease. These abnormalities of lung function appear to be secondary to the musculoskeletal disorder associated with prune-belly syndrome rather than parenchymal lung disease.  相似文献   
56.

Purpose

Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.

Materials and methods

Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.

Results

A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10 cm (IQR: 8–12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).

Conclusions

The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates.  相似文献   
57.
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in a prospective study of 48 patients for the detection of metastatic mediastinal lymphadenopathy from bronchogenic carcinoma. The images were interpreted by three experienced radiologists using a five-point rating scale, enabling receiver operating characteristic (ROC) analysis. Imaging results were evaluated against "truth" data based on analysis of surgical specimens from mediastinoscopy and thoracotomy. All MR images were cardiac gated to reduce cardiac motion artifacts in the mediastinum. MR and CT both performed well, as indicated by similar areas under the ROC curves of 0.779 +/- 0.039 for MR imaging and 0.781 +/- 0.038 for CT scanning. No strong correlation between nodal size and metastatic involvement could be found for either MR or CT results. As long as nodal size remains the sole criterion in the detection of metastatic mediastinal lymphadenopathy, MR imaging is unlikely to enable better interpretations than CT scanning.  相似文献   
58.
59.
Posttransfusion purpura following bone marrow transplantation   总被引:1,自引:0,他引:1  
BACKGROUND : Thrombocytopenia is a major cause of morbidity and hospital expense following bone marrow transplantation. Platelet transfusions in these patients are frequently complicated by the recipient's development of antibodies to HLA class I antigens. When these patients become refractory to the transfusion of HLA-matched platelets, the recipient's platelet antigen phenotype must be determined, to ensure that donor platelets will be phenotypically compatible. Cases of alloimmunization to HPA-1a and HPA-1b resulting in refractoriness to transfused platelets and the subsequent development of a posttransfusion purpura-like syndrome are reported. CASE REPORTS: In the first case, a 43-year-old woman with Stage IV infiltrating ductal breast cancer presented to the hospital for a transplant of autologous peripheral blood stem cells. After the transplant, her platelet count remained less than 10 × 109 per L, despite daily platelet transfusions, including HLA-matched platelets. Fourteen days following the transplant, her serum was found to contain anti-HPA-1a. Initially, the patient was refractory to the transfusion of HPA-1a-negative platelets, but after treatment with intravenous immunoglobulin, she had transient increases in posttransfusion platelet counts. She was also treated with a staphylococcal protein A immunoadsorption column and has not had any such subsequent refractoriness. Her genotype has been found, by use of allele-specific oligonucleotide hybridization with white cell DNA, to be HPA-1b/1b. The second case involved a 32-year-old woman with chronic myelogenous leukemia who received an unrelated-donor marrow transplant. Three years later, her CML recurred, and she was treated with interferon-alpha. Four months afterward, she experienced interferon-alpha-induced thrombocytopenia and the interferon therapy was discontinued. She received 12 platelet transfusions in 20 days, but none was effective. Antibodies specific for HLA antigens and HPA-1b were detected, and three HLA-matched, HPA-1b-negative apheresis platelet components were given, but without effect. Two days after treatment with methylprednisolone (1 g intravenously) and prednisone (2 mg/kg/day orally), her platelet count was 26 × 109 per L, and after 8 more days, it was 102 × 109 per L, without further transfusions. She was found to be homozygous for HPA-1a (HPA-1a/1a). CONCLUSION : Anti-HPA- 1a and anti-HPA-1b can cause refractoriness to platelet transfusions in bone marrow transplant patients. Testing for platelet-specific antibodies should be considered in all patients who are refractory to HLA-matched platelets.  相似文献   
60.
BACKGROUND: Chloramphenicol-dependent antibodies are a rare cause of interference in pretransfusion serologic testing. Their presence can be confirmed by the testing of red cells in both the presence and absence of chloramphenicol. CASE REPORT: A 29-year-old, group A, Rh-positive man with no history of chloramphenicol exposure was found to have a chloramphenicol-dependent panagglutinin in his serum. The antibody was IgM with a titer of 8. It showed no blood group specificity when tested with common and rare red cell phenotypes, and it failed to react with platelets and granulocytes. Confirmation attempts using a chloramphenicol sodium succinate solution as the cell-suspending medium led to negative results. The antibody reacted serologically only in the presence of chloramphenicol, which arises from the succinate derivative by the action of blood esterases. CONCLUSION: This case is an additional example of a chloramphenicol-dependent antibody. It demonstrates how the laboratory investigation of drug-related phenomena is dependent on testing the drug from that reacts in vivo.  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