全文获取类型
收费全文 | 2319篇 |
免费 | 100篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 124篇 |
儿科学 | 92篇 |
妇产科学 | 94篇 |
基础医学 | 106篇 |
口腔科学 | 63篇 |
临床医学 | 171篇 |
内科学 | 610篇 |
皮肤病学 | 55篇 |
神经病学 | 89篇 |
特种医学 | 106篇 |
外科学 | 545篇 |
综合类 | 40篇 |
预防医学 | 48篇 |
眼科学 | 74篇 |
药学 | 67篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 150篇 |
出版年
2024年 | 3篇 |
2023年 | 14篇 |
2022年 | 23篇 |
2021年 | 50篇 |
2020年 | 41篇 |
2019年 | 38篇 |
2018年 | 54篇 |
2017年 | 51篇 |
2016年 | 77篇 |
2015年 | 74篇 |
2014年 | 103篇 |
2013年 | 139篇 |
2012年 | 195篇 |
2011年 | 165篇 |
2010年 | 92篇 |
2009年 | 87篇 |
2008年 | 187篇 |
2007年 | 208篇 |
2006年 | 165篇 |
2005年 | 169篇 |
2004年 | 136篇 |
2003年 | 112篇 |
2002年 | 97篇 |
2001年 | 33篇 |
2000年 | 21篇 |
1999年 | 14篇 |
1998年 | 15篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1974年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有2437条查询结果,搜索用时 31 毫秒
61.
The aim of this investigation was to compare the traditional method of manual cephalometric tracing with four different computerized tracing programs, where the lateral cephalograms were scanned at 300 dpi and digitized onscreen. Thirty randomly selected cephalometric radiographs were used in this study. Four programs Dolphin Imaging, Vistadent, Nemoceph, and Quick Ceph were evaluated. Three dental, 11 skeletal, and 1 soft tissue parameters were measured that consisted of 5 linear and 10 angular measurements. Statistical analysis was carried out using multivariate analysis of variance and Box's and Levene's tests. No statistically significant difference was found between manual tracing and the computerized tracing programs. The measurements obtained with the cephalometric analysis programs used in the study were reliable. 相似文献
62.
Neurological Sciences - This study aims to evaluate the differences in the sizes and configurations of various structures on brain MRIs of patients with intracranial hypotension (ICH) compared to... 相似文献
63.
64.
Dincer U Cakar E Kiralp MZ Bozkanat E Kilac H Dursun H 《The Tohoku journal of experimental medicine》2007,212(4):423-430
Rheumatic diseases are chronic inflammatory diseases which cause mild to severe functional loss and disability due to articular and extra-articular manifestations. One common form -ankylosing spondylitis (AS)- affects mainly the axial skeleton and sacroiliac joints, and certain extra-articular organs. The pulmonary involvement is a known manifestation of AS and emerges either in the form of interstitial lung disease or in the form of restricted pulmonary functions. The aim of this study is to determine the pulmonary functions in AS patients and to assess its relationship with quality of life, functionality and disease activity. Thirty-six AS patients and 34 healthy volunteers were recruited for the study. A detailed examination, pulmonary function tests, smoking inquiry and quality of life questionnaire were performed on all participants. Also patients were requested to complete functionality and disease activity indexes. The outcomes showed that 15 (41.7%) AS patients had pulmonary involvement: twelve patients with restrictive patterns, one with obstructive pattern, and two with both restrictive and obstructive patterns. Decreased forced expiratory volume in one second was associated with deteriorated functionality (p < 0.05). Decreased chest expansion was also accompanied with decreased forced vital capacity (p < 0.05). There was no statistically significant difference between the smoking and non-smoking patients in regard to disease activity, functionality and pulmonary function test variables (p > 0.05). In conclusion, the pulmonary involvement is common in AS and might have disturbed functionality and the quality of life in AS patients. 相似文献
65.
In this study we have reported a 12-year old girl patient who visited out-patient clinic with the history of headache and convulsion. The patient was diagnosed as miliary tuberculosis and multiple brain tuberculomas. Miliary infiltration was observed in chest x-ray and high-resolution thorax computed tomography (CT), and multiple tuberculomas surrounded with wide edema was observed in Magnetic Resonance Imaging (MRI). Acid-fast bacilli were detected in inducted sputum and gastric fluid. Focal epileptiform activity was seen in electroencephalography (EEG). The patient was administered antitubercular, anti-edema and antiepileptic therapy. The patient had not experienced convulsion for the second time and EEG had been normal; therefore her treatment was completed within 12 months. Chest x-ray and high-resolution thorax CT findings turned to normal and brain MRI findings improved significantly. As a conclusion, tuberculosis disease has very different clinical pattern depending on the organs it involves. The significance of our case is due to the presence of both the miliary tuberculosis and intracranial tuberculomas. The patient was admitted to the hospital due to central nervous system symtoms rather than pulmonary symptoms. 相似文献
66.
Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu2Si monolayer. Pristine Cu2Si, a metallic monolayer, has a planar hexacoordinate structure. Calculations revealed that the most favorable position of a single H atom on the Cu2Si monolayer is at the top of a Si site. Derivatives of Cu2Si monolayer with various H concentrations were investigated, and by performing phonon calculations, it was found that there are three stable hydrogenated structures. Specific heat of these monolayers was found to increase with the hydrogen concentration at temperatures higher than 100 K. Electronically, the hydrogenated derivatives of Cu2Si monolayer preserve the metallic character.Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu2Si monolayer. 相似文献
67.
Dural K Han S Yildirim E Koçer B Kandemir M Ozişik K Sakinci U 《Tüberküloz ve toraks》2005,53(1):57-61
Thoracostomy tube placement (TT) is currently one of the most important treatment modalities used in traumatic pneumothorax patients. In patients with low pneumothorax ratio (percentage), both follow-up without surgery and employing intervention when indicated may be appropriate choice. We presented the outcome of patients with low traumatic pneumothorax ratio treated by follow up without surgical intervention in our clinic. During the period from January 2000 until January 2002, 108 patients who were treated and followed with low percentage traumatic pneumothorax in Ankara Numune Hospital Thoracic Surgery Clinic were allocated into three groups due to blunt trauma of the thorax, penetrating-cutting instrument injury and gunshot injury. All patients were admitted to the clinic with the purpose of observation without surgical intervention and chest roentgenograms were taken at the sixth and twelfth hours and daily thereafter. TT was performed for 46 (43%) patients whose pneumothorax ratio increased during the observation period. TT was more frequent in patients with 20% percentage pneumothorax (69%) as well as with two or more fractured ribs (69%). Follow-up without surgical intervention may one of the appropriate modes of treatment in patients who have minimal traumatic pneumothorax. 相似文献
68.
Emin Turk Erdal Karagulle Gokcen Coban Erkan Yildirim Gokhan Moray 《International surgery》2014,99(2):147-152
We sought to investigate whether application of topical tetracycline has a limiting effect on seroma formation in patients undergoing hernia repair using a polypropylene mesh. This study was conducted in 96 patients undergoing an elective groin hernia repair. Patients were randomized and divided into 2 groups. After the graft was placed, and before external oblique muscle aponeurosis was closed, 5 mL tetracycline was administered on the graft in the tetracycline group (tetra group, n = 50), and 5 mL isotonic saline was administered in the control group (n = 46) without putting in a drain. Seroma checks via surface ultrasonography were done. Seroma amounts measured on the first day were significantly higher in the tetra group (P = 0.04). There were no significant differences regarding seroma measurements on the seventh day or in the first and second months. Topical tetracycline application has no limiting effect on seroma formation after a groin hernia operation.Key words: Lichtenstein technique, Polypropylene mesh, Topical tetracycline, Seroma, UltrasonographyHernia operations are among the most frequently performed surgical operations. Graft use to repair the defect is commonplace because graft use decreases recurrence rate, and defect closure in large abdominal hernias is easier with a mesh.1 The most commonly used and least expensive mesh is the polypropylene mesh. This mesh causes a foreign-body reaction where it is placed, which leads to seroma formation.2 Repeat aspirations of seromas cause infection, and recurrence is seen on follow-up, especially in large hernias.2 While drain use is not recommended in groin hernias, drain use in other abdominal-wall hernias is left to the physician''s discretion. The biggest problem with drain use is transport of the infection by an ascending route.3Tetracycline is an antibiotic, the solution form of which is topically used for pleurodesis in chest surgery.4 Some researchers also report successful topical use of its solution in seroma treatment, taking advantage of its sclerosing effect in cases with breast carcinoma.5,6 Tetracycline has demonstrated increased growth factor–like activity in mesothelial cells exposed to tetracycline leading to fibroblast proliferation.7 This study sought to investigate whether tetracycline has a reducing effect on seroma development in cases undergoing elective groin hernia repair using a polypropylene mesh. 相似文献
69.
Mehmet Erkan Kaplama Ahmet Kürşad Güneş Burak Erden 《Revista brasileira de otorrinolaringologia (English ed.)》2021,87(2):210-216
IntroductionThe diagnostic approach to patients with isolated asymptomatic cervical lymphadenopathy varies between excisional biopsy and follow-up. When the anamnesis, physical examination, laboratory and imaging findings are not sufficient to identify the etiology, an excisional biopsy is performed for the differential diagnosis between early-stage lymphoma and infectious or reactive causes. If the excisional biopsy, which may have some complications, is not performed, it may delay the diagnosis of lymphoma. This diagnostic challenge could be avoided by predictive markers.ObjectivesThis study was planned to determine the predictive value of neutrophil/lymphocyte ratio in the diagnosis of Hodgkin and non-Hodgkin limphoma in patients with asymptomatic, isolated cervical limphadenopathy and underwent excisional biopsy.MethodsA total of 90 patients between the years 2016 ? 2019 admitted to our clinics due to asymptomatic isolated cervical lymphadenopathy, present in at least 4 weeks with lympho nodes in pathological dimensions persisting in the cervical region, were included to our study. An excisional lympho node biopsy was performed in all 90 patients.ResultsOf the 90 patients who underwent excisional biopsy; 34 were diagnosed as reactive lymphadenopathy 30 were non-Hodgkin linphoma, and 26 were Hodgkin linphoma. A total of 56 (62.2%) patients were diagnosed as lymphoma, either Hodgkin or non-Hodgkin, while 34 patients (38.8%) were diagnosed as reactive lymphadenopathy. The median age, total whiteblood count, neutrophil count of the lymphoma groups were significantly higher than reactive lymphadenopathy group, whereas the lymphocyte count was significantly lower in the lymphoma patients. The median neutrophil/ lymphocyte ratio was 1.7 in the reactive lymphadenopathy group, 3.5 in the non-Hodgkin limphoma group, and 3.0 in the Hodgkin limphoma group (p < 0.001).ConclusionAccording to the results of our study, neutrophil/lymphocyte ratio was significantly higher in patients who were admitted with isolated asymptomatic lymphadenopathy and were diagnosed with lymphoma, and who were diagnosed with early-stage Hodgkin and non- Hodgkin lymphoma compared to those who were found to have reactive lymphadenopathy. Neutrophil/lymphocyte ratio, which is a low-cost, fast and easy-to-access test, has a predictive value in the diagnosis of lymphoma in patients with asymptomatic lymphadenopathy. 相似文献
70.
Hemoptysis is symptomatic of potentially serious and life-threatening chest disease and requires urgent evaluation and treatment. The aim of this study was to evaluate the hemostatic efficacy of endobronchial application of Ankaferd Blood Stopper® (ABS) solution in patients with hemoptysis. 相似文献