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   1639篇
  免费   90篇
  国内免费   6篇
耳鼻咽喉   33篇
儿科学   65篇
妇产科学   61篇
基础医学   174篇
口腔科学   77篇
临床医学   122篇
内科学   338篇
皮肤病学   26篇
神经病学   75篇
特种医学   82篇
外科学   402篇
综合类   21篇
预防医学   43篇
眼科学   91篇
药学   83篇
中国医学   1篇
肿瘤学   41篇
  2024年   1篇
  2023年   8篇
  2022年   10篇
  2021年   40篇
  2020年   22篇
  2019年   39篇
  2018年   46篇
  2017年   42篇
  2016年   59篇
  2015年   82篇
  2014年   97篇
  2013年   118篇
  2012年   132篇
  2011年   134篇
  2010年   67篇
  2009年   56篇
  2008年   116篇
  2007年   107篇
  2006年   89篇
  2005年   94篇
  2004年   105篇
  2003年   67篇
  2002年   54篇
  2001年   40篇
  2000年   25篇
  1999年   29篇
  1998年   7篇
  1997年   5篇
  1996年   5篇
  1995年   4篇
  1994年   5篇
  1992年   4篇
  1991年   2篇
  1990年   5篇
  1989年   6篇
  1988年   5篇
  1987年   4篇
  1985年   1篇
  1984年   1篇
  1982年   1篇
  1980年   1篇
排序方式: 共有1735条查询结果,搜索用时 31 毫秒
1.
2.
A case of synovial chondromatosis of the proximal tibiofibular joint in addition to lateral and medial tibiofemoral spaces and patellofemoral joint has been presented.  相似文献   
3.
BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder characterised by platelet aggregation causing microvascular occlusion. Early diagnosis and utilization of plasmapheresis can provide an improvement in prognosis. CASE REPORT: A 17 year old male with classical findings of TTP was later diagnosed as systemic lupus erythematosus (SLE). Plasmapheresis resulted in the significant amelioration of the course. CONCLUSION: The coexistence of TTP and SLE may facilitate a better understanding of in the pathophysiology of TTP. These association may provide the role of autoimmunity in TTP. SLE should be considered in the differential diagnosis of patients with TTP because of therapeutic implications.  相似文献   
4.
5.
The various methods of prefabricating flaps include vascular induction through staged transfer; pretransfer delay, expansion, and grafting; the use of alloplastic materials; and tissue bioengineering. In this experimental study, vascular induction was used to provide an axial vascular pedicle to randomly nourished tissue. Twenty-six New Zealand rabbits, ages and weights ranging between 6 months-1 year and 1.5-3.5 kg, respectively, were used. The sex difference was not considered. The deep inferior epigastric artery and vein were used to carry blood and were placed into a segment of femur to prefabricate the bone. Four weeks later, the viability of the segment of bone prefabricated by new axial pedicle was shown by scintigraphic study, and the new axial pedicle was ready for free transfer.  相似文献   
6.
Asthma and allergic rhinitis are common problems in children and the causative pollen allergens vary according to the geographical area. The aim of this study was to investigate patterns of sensitization to common inhalant allergens, especially pollens, in Turkish children living in the Trakya region and to determine differences between rural and urban areas. Allergen skin testing was prospectively performed on 539 children aged between 4 and 17 years with respiratory allergy. The reaction was considered to be positive if the mean wheal diameter was at least 3 mm greater than that of the negative controls. We detected positive skin reactions in 420 (77.9%) children. Two hundred and eighty-one (52.1%) mite, 277 (51.4%) pollen, 174 (32.3%) mold, 65 (12.1%) animal dander, 12 (2.2%) cockroach and 6 (1.1%) latex skin sensitivities were detected. Among the pollen allergies 173 were cereal pollen (32.1%), 170 grass pollen (31.5%) and 144 tree pollen allergies (26.7%). The most common positive skin test among the pollens was to cultivated wheat (Titicum vulgare) (n = 116, 21,5%), followed by rye grass (Lolium perenne) and orchard grass (Dactylis glomerata). Positive skin reactions to Alternaria, to Candida albicans, and to all pollens except Ulmus competris, Pinus sylvetris, Platanus vulgaris and Tilia platyphyllos, were higher in children with allergic rhinitis than in those with asthma. In children from rural areas, allergic skin reactivity was found to be more common against Candida albicans, sheep dander and all pollens except Corylus avellana, Fraxinus excelsior, Populus alba, Pinus sylvetris, Platanus vulgaris and Chenopodium album, than in urban children. Although Trakya is close to Greece and other Mediterranean countries, this study suggests that the pollens, which sensitize children, are not similar.  相似文献   
7.
This study was made because of the difficulty of resuscitating Mycoplasma meleagridis from agar cultures received from the field. The type strain of Mm was found viable following culture at 37 degrees C for as long as 10 days and maintenance at room temperature for a further 14 days but only when few colonies were present in the original culture. It is suggested that for the satisfactory subculture of this organism the original culture on mycoplasma agar should not exceed 1 week, or no more than a few days should the colonies appear after this time, and that the period at room temperature should also not exceed 1 week. Non-viable colonies, if small, may however be recognised by immunofluorescence.  相似文献   
8.
Objectives: To determine whether patients with idiopathic systemic lupus erythematosus (SLE) are associated with impaired CYP2D6 activity and to gain insight into whether there is an association between particular CYP2D6 genotypes and susceptibility to SLE, and whether CYP2D6 polymorphism is linked to any specific clinical features of SLE. Methods: Debrisoquine sulfate (10 mg p.o.) was given to 159 healthy volunteers and 39 idiopathic SLE patients. Genotypic assay was carried out in 80 healthy volunteers and 32 patients. A 10-ml blood sample was drawn for genotypic assay. Debrisoquine and 4-hydroxydebrisoquine were determined in 8-h urine samples. Blood samples were analysed for the presence of mutations in the CYP2D6 gene, by using polymerase chain reaction (PCR) specific for CYP2D6*3 and CYP2D6*4 alleles. Results: The metabolic ratio of debrisoquine to 4-hydroxydebrisoquine ranged from 0.01 to 86.98 in healthy subjects and from 0.02 to 96 in SLE patients. We observed the poor metabolizer(PM) debrisoquine phenotype in three of 39 patients with idiopathic SLE (7.6%) and five of 159 healthy subjects (3.1%). There was no significant difference in the frequency of PM phenotypes between idiopathic SLE and healthy subjects (Fisher's exact test, P = 0.19). No significant difference in the distribution of overall genotypes and allele frequencies were observed between the two groups. No significant relationships were found between specific clinical features and the overall genotype. Conclusion: The results of this study confirm that CYP2D6 activity is not impaired in SLE and that there is no association between SLE and phenotypic CYP2D6 status. The results also showed that there was no difference in the frequency of CYP2D6A and CYP2D6B alleles between controls and patients with SLE. Received: 14 May 1998 / Accepted in revised form: 19 October 1998  相似文献   
9.
The purpose of this study was to evaluate the effects (common haemodynamic variables, peak cuff pressures, the incidence of reaction ('bucking') during extubation and the incidence of sore throat after operation) of lidocaine 10% instilled into the endotracheal tube cuff in intubated patients. Plasma concentrations of lidocaine were assayed. Seventy ASA class I-II patients scheduled for plastic surgery were studied. Patients were randomly divided in two groups: the cuff of the endotracheal tube was inflated with either lidocaine 10% (group L) or with saline (group S) immediately after endotracheal intubation. In group L patients, the haemodynamic changes were less (P < 0.05), and the peak cuff pressure was lower (P < 0.01) than for group S. At extubation, more patients reacted ('bucked') in group S (70.5% vs. 19.4%, P < 0.01). The incidence and severity of sore throat were significantly lower in group L 1 and 24-h after extubation. Plasma lidocaine concentrations did not reach toxic values. Lidocaine 10%, compared with saline, in the endotracheal tube cuff was associated with less disturbance of haemodynamic responses and less incidence of bucking during tracheal extubation. Lidocaine was also effective in reducing of incidence and severity of sore throat after operation.  相似文献   
10.
OBJECTIVE: Hydatid disease is a parasitosis and endemic in many sheepraising areas; it is still an important health problem in Turkey. We report our experience with childhood hydatid cyst and discuss the concepts of treatment. METHODS: The clinical courses of 128 children with thoracic and liver hydatid cyst operated on from 1994 to 2000 were reviewed. The group consisted of 71 boys and 57 girls aged from 8 months to 16 years. Intact cysts were found in 144 patients and ruptured cysts in 68. RESULTS: In the postoperative course we have encountered 20 perioperative complications in 16 patients. The most common complication was residual pleural space and delayed air leakage, which occurred in 9 patients. There was no early death. CONCLUSION: Surgery is the treatment of choice for most patients with pulmonary hydatid disease. The aim of surgery is evacuation of the cyst, removal of the endocyst, and management of the residual cavity. Conservative surgical methods that preserve lung parenchyma should be preferred.  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