全文获取类型
收费全文 | 2174篇 |
免费 | 151篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 127篇 |
妇产科学 | 84篇 |
基础医学 | 209篇 |
口腔科学 | 54篇 |
临床医学 | 281篇 |
内科学 | 372篇 |
皮肤病学 | 29篇 |
神经病学 | 52篇 |
特种医学 | 412篇 |
外科学 | 196篇 |
综合类 | 25篇 |
一般理论 | 13篇 |
预防医学 | 227篇 |
眼科学 | 23篇 |
药学 | 54篇 |
肿瘤学 | 131篇 |
出版年
2023年 | 9篇 |
2021年 | 23篇 |
2020年 | 12篇 |
2019年 | 19篇 |
2018年 | 29篇 |
2017年 | 21篇 |
2016年 | 21篇 |
2015年 | 32篇 |
2014年 | 47篇 |
2013年 | 65篇 |
2012年 | 76篇 |
2011年 | 72篇 |
2010年 | 70篇 |
2009年 | 59篇 |
2008年 | 67篇 |
2007年 | 99篇 |
2006年 | 75篇 |
2005年 | 80篇 |
2004年 | 67篇 |
2003年 | 44篇 |
2002年 | 55篇 |
2001年 | 43篇 |
2000年 | 48篇 |
1999年 | 55篇 |
1998年 | 105篇 |
1997年 | 78篇 |
1996年 | 83篇 |
1995年 | 57篇 |
1994年 | 60篇 |
1993年 | 68篇 |
1992年 | 18篇 |
1991年 | 20篇 |
1990年 | 21篇 |
1989年 | 48篇 |
1988年 | 33篇 |
1987年 | 44篇 |
1986年 | 28篇 |
1985年 | 39篇 |
1984年 | 35篇 |
1983年 | 22篇 |
1982年 | 25篇 |
1981年 | 29篇 |
1980年 | 36篇 |
1979年 | 15篇 |
1978年 | 19篇 |
1977年 | 26篇 |
1976年 | 25篇 |
1975年 | 19篇 |
1922年 | 14篇 |
1921年 | 13篇 |
排序方式: 共有2339条查询结果,搜索用时 0 毫秒
101.
Postembolic colonic infarction 总被引:12,自引:0,他引:12
102.
103.
Silva P Bruce IA Malik T Homer J Banerjee S 《The Journal of laryngology and otology》2005,119(1):8-11
Nodular fasciitis is an unusual benign reactive process affecting superficial and deep fascia. Its rapid growth, rich cellularity, high mitotic activity and poorly circumscribed nature result in it being easily misdiagnosed as a sarcomatous lesion. Three cases of nodular fasciitis presenting as neck lumps are reported. They were successfully treated with local excision, with no signs of recurrence following two years of follow up. This paper describes the clinical presentation and microscopic features of this rare benign lesion and it emphasizes the need for accurate histopathology and clinical suspicion, if inappropriate aggressive management is to be avoided. 相似文献
104.
Hyperbaric oxygen therapy, a treatment alternative for chronic wounds, has been used for several decades yet little is known about factors that influence physicians to incorporate this therapy into practice. To assess wound care physician knowledge of, attitudes toward, and adoption of hyperbaric oxygen therapy and to identify factors associated with physician adoption of this therapy, a 23-item questionnaire, based on Rogers' diffusion of innovation model, was developed by the authors and distributed to 653 American Academy of Wound Management Board-certified physicians. Of the 246 (43%) physicians in the study population who responded to the study survey, 167 (68%) reported they had used or referred patients for hyperbaric oxygen therapy during the past 12 months. More than half of the respondents reported a relatively high level of familiarity with and a positive attitude toward the effects of hyperbaric oxygen therapy on wound healing. Physician adoption of hyperbaric oxygen therapy was significantly associated with a community of >100,000 residents (adjusted odds ratio = 2.29, 95% confidence interval = 1.05 to 5.04); patient request for hyperbaric oxygen therapy (adjusted odds ratio = 5.38, 95% confidence interval = 2.50 to 11.56); positive attitude toward (adjusted odds ratio = 3.38, 95% confidence interval = 1.49 to 7.66) and high level of familiarity with hyperbaric oxygen therapy (adjusted odds ratio = 5.33, 95% confidence interval = 1.72 to 6.49); and practice location in either Florida or Texas (adjusted odds ratio = 3.44, 95% confidence interval = 1.24 to 9.54). Although the majority of the respondents reported adoption of hyperbaric oxygen therapy, most adopters are concentrated only in a few geographic areas. Despite the limitations of this study, especially the potential effects of sampling and response bias, the results help explain factors that have facilitated and hindered the adoption of this technology into practice. 相似文献
105.
Focal FDG uptake in mediastinal brown fat mimicking malignancy: a potential pitfall resolved on PET/CT 总被引:11,自引:0,他引:11
Truong MT Erasmus JJ Munden RF Marom EM Sabloff BS Gladish GW Podoloff DA Macapinlac HA 《AJR. American journal of roentgenology》2004,183(4):1127-1132
OBJECTIVE: A potential source of false-positive FDG PET interpretations in oncologic imaging is FDG uptake in brown fat. The purpose of this study was to determine the prevalence, location, and appearance of hypermetabolic brown fat in the mediastinum. MATERIALS AND METHODS: All PET/CT scans obtained at our cancer institution from August to October 2003 were retrospectively reviewed for increased FDG uptake in the mediastinum localized to fat on CT. The following features were recorded: location, appearance, maximal standard uptake value (SUV(max)) of hypermetabolic mediastinal brown fat, and presence of extramediastinal brown fat. RESULTS: PET/CT scans were obtained in 845 oncologic patients. Fifteen patients (1.8%) with focal hypermetabolic mediastinal brown fat were identified: nine women and two men (age range, 27-79; mean, 55.1 years) and four children (age range, 5-16 years; mean, 10 years). Hypermetabolic mediastinal brown fat (mean SUV(max), 5.7) was more common in children (4/8) than in adults (11/837) and more common in women (9/372) than in men (2/465). Foci of hypermetabolic brown fat were localized to the paratracheal, paraesophageal, prevascular, and pericardial regions; interatrial septum; and azygoesophageal recess. Five patients had focal hypermetabolic brown fat isolated to the mediastinum. Ten patients also had extramediastinal hypermetabolic brown fat in the neck, thorax, and abdomen. There was no difference in the body weight (p = 0.876) or body mass index (p = 0.538) of patients with hypermetabolic brown fat compared with age- and sex-matched control subjects. CONCLUSION: Hypermetabolic brown fat can be localized to the mediastinum and manifests as focal increased FDG uptake. Knowledge of this potential pitfall and precise localization with fusion PET/CT are important in preventing misinterpretation as malignancy. 相似文献
106.
Alveolar macrophages from HIV-infected subjects are resistant to Mycobacterium tuberculosis in vitro
Day RB Wang Y Knox KS Pasula R Martin WJ Twigg HL 《American journal of respiratory cell and molecular biology》2004,30(3):403-410
HIV-infected individuals frequently develop Mycobacterium tuberculosis (MTB) infection. Alveolar macrophages (AM) are the initial host defense against this organism. We measured MTB growth in AM from normal and HIV-infected subjects after in vitro exposure. Intracellular growth of MTB was reduced in AM from HIV-infected subjects compared with normal macrophages. This was confined to subjects with CD4 counts greater than 200/microl. Growth of avirulent mycobacteria in HIV macrophages was significantly less than virulent MTB. Because avirulent MTB is more sensitive to tumor necrosis factor-alpha (TNF-alpha), we examined the relationship between cytokine secretion and mycobacterial growth. Higher AM spontaneous TNF-alpha secretion was associated with reduced MTB growth in normal AM. This relationship was not seen in HIV-infected subjects, suggesting that other factors contributed to mycobacteria resistance. Mycobacteria-induced TNF-alpha secretion was inversely associated with growth in normal AM but not in HIV-infected subjects. Finally, binding and internalization of MTB was augmented in HIV macrophages compared with normal, demonstrating that reduced intracellular MTB growth was not due to impaired phagocytosis. In conclusion, the increased incidence of MTB infection in HIV-infected subjects does not appear to be due to a defect in macrophage innate immunity. 相似文献
107.
108.
109.
Passant L Homer C Wills J 《Australian journal of midwifery : professional journal of the Australian College of Midwives Incorporated》2003,16(4):18-21
In 2001, a new model of midwifery care was established in the Birth Centre at St George Hospital, a metropolitan hospital in NSW. The new model was designed to encompass the principles and recommendations from numerous government reports and research. The model also build on the previous successful implementation of a team midwifery program (Homer et al 2001b; Homer et al 2001a). Four newly graduated midwives, together with four more experienced midwives were employed to work in the models of midwifery care. This small study evaluates the first 10 months' using qualitative and quantitative data. As this is a small study, no firm conclusion can be reached. The results of the evaluation however demonstrated that with appropriate support and mentoring, newly graduated midwives can work in an innovative model of midwifery care within a birth centre environment. 相似文献
110.
Flying at altitude soon after myringoplasty may theoretically have an adverse effect on graft take rates owing to variation in external air pressure, together with suboptimal Eustachian tube function, causing graft displacement. We wished to assess the effect of flying after myringoplasty by comparing success rates of patients flying within a week postoperatively (n = 37) with a control group (n = 37) by carrying out a retrospective, controlled cohort study. The primary outcome measure was graft success, defined as a 100% closure at first outpatient follow-up (2.5 months). Our results showed that there was no difference in early graft success rates between the flying group (32/37: 86%) and non-flying group (29/37: 78%)(P = 0.32; 95% CI of difference: -9% to 27%). In conclusion, flying at altitude in a pressurized environment within a week of myringoplasty does not adversely affect early operative success. 相似文献