全文获取类型
收费全文 | 1981篇 |
免费 | 111篇 |
国内免费 | 75篇 |
学科分类
医药卫生 | 2167篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 11篇 |
2020年 | 14篇 |
2019年 | 15篇 |
2018年 | 31篇 |
2017年 | 22篇 |
2016年 | 22篇 |
2015年 | 39篇 |
2014年 | 47篇 |
2013年 | 57篇 |
2012年 | 34篇 |
2011年 | 37篇 |
2010年 | 88篇 |
2009年 | 84篇 |
2008年 | 50篇 |
2007年 | 87篇 |
2006年 | 50篇 |
2005年 | 53篇 |
2004年 | 24篇 |
2003年 | 17篇 |
2002年 | 27篇 |
2001年 | 36篇 |
2000年 | 28篇 |
1999年 | 28篇 |
1998年 | 128篇 |
1997年 | 155篇 |
1996年 | 131篇 |
1995年 | 108篇 |
1994年 | 114篇 |
1993年 | 97篇 |
1992年 | 28篇 |
1991年 | 35篇 |
1990年 | 36篇 |
1989年 | 54篇 |
1988年 | 46篇 |
1987年 | 42篇 |
1986年 | 49篇 |
1985年 | 45篇 |
1984年 | 26篇 |
1983年 | 15篇 |
1982年 | 24篇 |
1981年 | 29篇 |
1980年 | 25篇 |
1979年 | 4篇 |
1978年 | 8篇 |
1977年 | 18篇 |
1976年 | 25篇 |
1975年 | 14篇 |
1966年 | 1篇 |
排序方式: 共有2167条查询结果,搜索用时 15 毫秒
101.
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone. 相似文献
102.
Adrian B Levine Jason Peng David Farnell Mitchell Nursey Yiping Wang Julia R Naso Hezhen Ren Hossein Farahani Colin Chen Derek Chiu Aline Talhouk Brandon Sheffield Maziar Riazy Philip P Ip Carlos Parra-Herran Anne Mills Naveena Singh Basile Tessier-Cloutier Taylor Salisbury Jonathan Lee Tim Salcudean Steven JM Jones David G Huntsman C Blake Gilks Stephen Yip Ali Bashashati 《The Journal of pathology》2020,252(2):178-188
Deep learning-based computer vision methods have recently made remarkable breakthroughs in the analysis and classification of cancer pathology images. However, there has been relatively little investigation of the utility of deep neural networks to synthesize medical images. In this study, we evaluated the efficacy of generative adversarial networks to synthesize high-resolution pathology images of 10 histological types of cancer, including five cancer types from The Cancer Genome Atlas and the five major histological subtypes of ovarian carcinoma. The quality of these images was assessed using a comprehensive survey of board-certified pathologists (n = 9) and pathology trainees (n = 6). Our results show that the real and synthetic images are classified by histotype with comparable accuracies and the synthetic images are visually indistinguishable from real images. Furthermore, we trained deep convolutional neural networks to diagnose the different cancer types and determined that the synthetic images perform as well as additional real images when used to supplement a small training set. These findings have important applications in proficiency testing of medical practitioners and quality assurance in clinical laboratories. Furthermore, training of computer-aided diagnostic systems can benefit from synthetic images where labeled datasets are limited (e.g. rare cancers). We have created a publicly available website where clinicians and researchers can attempt questions from the image survey ( http://gan.aimlab.ca/ ). © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
103.
104.
Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo. 相似文献
105.
106.
Ventilator-associated pneumonia (VAP) is a common cause of morbidity, antibiotic use, increased length of stay and, possibly,
increased mortality in ICU patients. Colonization of the oropharyngeal cavity with potentially pathogenic micro-organisms
is instrumental in the pathogenesis of VAP, and selective oropharyngeal decontamination (SOD) with antibiotics (AB-SOD) or
antiseptics, such as chlorhexidine gluconate (CHX-SOD), has been associated with reduced incidences of VAP. In a recent issue
of Critical Care Scannapieco and colleagues investigated differences in oropharyngeal colonization between mechanically ventilated patients
receiving oropharyngeal decontamination with 0.12% CHX-SOD either once or twice daily compared to placebo. CHX-SOD was associated
with a reduction in Staphylococcus aureus colonization, but the study was underpowered to demonstrate a reduction in VAP incidence. We urgently need well-designed
and adequately powered studies to evaluate the potential benefits of CHX-SOD on patient outcome in ICUs. 相似文献
107.
在当前医学教育持续变革的背景中,医学教师的专业发展成为广泛关注的焦点.为了解目前美国以提高教师的教学技能为目标的教师专业发展(faculty development,FD)活动的参与率、课程设计、教学方法和评估策略等情况,美国约翰·霍普金斯大学预防、流行病学和临床研究中心采取邮件调查的方式,对美国277家教学医院进行了调查. 相似文献
108.
A Levy Bencheton JM Berenger P Del Giudice P Delaunay F Pages JJ Morand 《Journal of the European Academy of Dermatology and Venereology》2011,25(5):599-602
Background Bedbugs (Cimex lectularius) have been feeding on sleeping human beings since prehistory. In Europe, bed bugs were common and endemic until World War II when improved body and home hygiene, and widespread use of insecticides led to almost complete eradication. Current evidence indicates that bedbugs are making a comeback in Europe, USA, Canada and Australia. In our practice in Southern France, we observed several cases within a period of only 1 year. Objectives Based on this experience, we conducted an epidemiological study to evaluate the status of bedbugs in France. Methods During summer 2009, we mailed a short questionnaire to all hospital professors in the CEDEF (Collège des Enseignants de Dermatologie de France) asking four questions: number of suspected diagnosis of bedbugs in the year 2009, and number of certain positive diagnosis, difficulties in treatment, use of a pest control professional for treatment, and finally personal opinion on actual incidence of bedbugs, compared with past years. Results Of the 84 questionnaires sent, there were only 26 responses despite two reminders. The responses were predominantly southern France, probably as a result of intensive immigration and increased travel and trade. Difficulties encountered during diagnosis and treatment are also mentioned. Utilizing the services of entomological experts and pest control professionals is essential. Conclusions France has the same experience regarding the resurgence of bedbugs as several European countries, USA, Canada and Australia, especially the southern regions. This emerging health problem has to be known by dermatologists. A national programme has been launched in France to assess actual incidence and study C. lectularius‐ related diseases. 相似文献
109.
JM Amici JY Bailly A Taieb 《Journal of the European Academy of Dermatology and Venereology》2010,24(3):308-316
Background Skin cancer surgery is usually performed on the face, and more specifically on and around the midfacial apertures. Each defect generated by the exeresis of a face tumor can be repaired by various advancement, rotation or transposition flaps techniques. Therefore the choice of the closure axis of a defect and its cicatricial and orificial consequences is decisive. Results The closure of a defect is usually made by symmetrically suturing its edges, across the incision axis according to the rule of halves. However, the closure axis of a defect is intentional and characterized by the subcutaneous suture axis which determines the induced tension orientation, and thus the possible displacement of the aperture free margins. The horizontal stretching principle guarantees the lack of impact on the 3 major apertures of the midfacial frame: eye, nostril and mouth. Conclusions This biomechanical concept is decisive to repair midfacial defect with functional and aesthetic results. It also provides objective arguments for the reparative techniques prioritization and the ability to codify those to be recommended as first‐line treatment in the surgical management of the face cutaneous tumours. 相似文献
110.
JM Toohey K Ismail D Lonergan CR Lewis 《Journal of Medical Imaging and Radiation Oncology》2007,51(6):594-596
Amyloid involvement of the breast is infrequently reported and may have clinical and radiological features suspicious for a primary breast malignancy. We describe a case of amyloid of the breast in which asymptomatic mammographic findings were suspicious for locally recurrent disease in a patient with previously treated breast cancer. 相似文献