全文获取类型
收费全文 | 1351篇 |
免费 | 65篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 45篇 |
妇产科学 | 27篇 |
基础医学 | 148篇 |
口腔科学 | 37篇 |
临床医学 | 166篇 |
内科学 | 253篇 |
皮肤病学 | 23篇 |
神经病学 | 29篇 |
特种医学 | 126篇 |
外科学 | 234篇 |
综合类 | 19篇 |
预防医学 | 51篇 |
眼科学 | 70篇 |
药学 | 119篇 |
肿瘤学 | 100篇 |
出版年
2021年 | 11篇 |
2018年 | 18篇 |
2017年 | 9篇 |
2016年 | 13篇 |
2015年 | 17篇 |
2014年 | 30篇 |
2013年 | 42篇 |
2012年 | 39篇 |
2011年 | 22篇 |
2010年 | 41篇 |
2009年 | 51篇 |
2008年 | 29篇 |
2007年 | 47篇 |
2006年 | 37篇 |
2005年 | 42篇 |
2004年 | 31篇 |
2003年 | 36篇 |
2002年 | 34篇 |
2001年 | 34篇 |
2000年 | 45篇 |
1999年 | 47篇 |
1998年 | 41篇 |
1997年 | 35篇 |
1996年 | 38篇 |
1995年 | 31篇 |
1994年 | 39篇 |
1993年 | 26篇 |
1992年 | 23篇 |
1991年 | 25篇 |
1990年 | 35篇 |
1989年 | 37篇 |
1988年 | 42篇 |
1987年 | 29篇 |
1986年 | 41篇 |
1985年 | 31篇 |
1984年 | 19篇 |
1983年 | 16篇 |
1982年 | 20篇 |
1981年 | 20篇 |
1980年 | 17篇 |
1979年 | 23篇 |
1978年 | 28篇 |
1977年 | 10篇 |
1976年 | 24篇 |
1975年 | 24篇 |
1974年 | 16篇 |
1973年 | 12篇 |
1970年 | 8篇 |
1969年 | 11篇 |
1968年 | 8篇 |
排序方式: 共有1450条查询结果,搜索用时 31 毫秒
101.
Emotional distress in patients with retinal disease 总被引:1,自引:0,他引:1
Scott IU Schein OD Feuer WJ Folstein MF Bandeen-Roche K 《American journal of ophthalmology》2001,131(5):584-589
PURPOSE: To investigate the prevalence of, and potential risk factors for, emotional distress among patients with retinal disease. DESIGN: Cross-sectional study. METHODS: Cases consisted of 86 consecutive patients at Wilmer Eye Institute Retinal Vascular Center. Fifty-one controls with normal visual acuity and no known ocular disease were frequency-matched to the cases by age, sex, and race. Subjects were interviewed using the Community Disability Scale, a functional status questionnaire, and the General Health Questionnaire, a questionnaire assessing emotional distress. RESULTS: The prevalence of probable (General Health Questionnaire score 4 or greater and less than 10) or definite (General Health Questionnaire score 10 or greater) emotional distress was 59.3% among ophthalmic patients and 2.0% among controls. There were significant relationships between emotional distress, as assessed by General Health Questionnaire score, and degree of 1) visual impairment, as assessed by weighted bilateral average logarithm of minimal angle of resolution (logMAR), and 2) functional impairment, as assessed by Community Disability Scale score (P =.001). Univariate analyses identified significant predictors of emotional distress: shorter duration of ocular disease (P =.019), worse visual acuity (P =.001), increased systemic comorbidities (P =.001), and increased functional impairment (P <.001). Multiple regression analysis demonstrates that worse visual acuity, increased systemic comorbidities, and shorter duration of ocular disease each explain over 10% of the variability in General Health Questionnaire score (r(2) = 0.15, 0.12, and 0.11, respectively). Addition of Community Disability Scale score to the regression model eliminates the significance of visual acuity and systemic comorbidities; Community Disability Scale score explains nearly 30% of the variability in emotional distress, as assessed by General Health Questionnaire score (r(2) = 0.29). CONCLUSIONS: Emotional distress is prevalent among patients with retinal disease; potential risk factors for emotional distress among such patients include shorter duration of ocular disease, worse visual acuity, increased systemic comorbidities, and increased functional impairment. 相似文献
102.
103.
104.
Treating hypertension with a device that slows and regularises breathing: a randomised, double-blind controlled study 总被引:1,自引:0,他引:1
Schein MH Gavish B Herz M Rosner-Kahana D Naveh P Knishkowy B Zlotnikov E Ben-Zvi N Melmed RN 《Journal of human hypertension》2001,15(4):271-278
OBJECTIVE: To examine the efficacy of a new device, which slows and regularises breathing, as a non-pharmacological treatment of hypertension and thus to evaluate the contribution of breathing modulation in the blood pressure (BP) reduction. DESIGN AND SETTING: Randomised, double-blind controlled study, carried out in three urban family practice clinics in Israel. PATIENTS: Sixty-five male and female hypertensives, either receiving antihypertensive drug therapy or unmedicated. Four patients dropped out at the beginning of the study. INTERVENTION: Self treatment at home, 10 minutes daily for 8 consecutive weeks, using either the device (n = 32), which guides the user towards slow and regular breathing using musical sound patterns, or a Walkman, with which patients listened to quiet music (n = 29). Medication was unchanged 2 months prior to and during the study period. MAIN OUTCOME MEASURES: Systolic BP, diastolic BP and mean arterial pressure (MAP) changes from baseline. RESULTS: BP reduction in the device group was significantly greater than a predetermined 'clinically meaningful threshold' of 10.0, 5.0 and 6.7 mm Hg for the systolic BP, diastolic BP and MAP respectively (P = 0.035, P = 0.0002 and P = 0.001). Treatment with the device reduced systolic BP, diastolic BP and MAP by 15.2, 10.0 and 11.7 mm Hg respectively, as compared to 11.3, 5.6 and 7.5 mm Hg (P = 0.14, P = 0.008, P = 0.03) with the Walkman. Six months after treatment had stopped, diastolic BP reduction in the device group remained greater than the 'threshold' (P < 0.02) and also greater than in the walkman group (P = 0.001). CONCLUSIONS: The device was found to be efficacious in reducing high BP during 2 months of self-treatment by patients at home. Breathing pattern modification appears to be an important component in this reduction. 相似文献
105.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely prescribed in the United States to treat pain and reduce inflammation from chronic inflammatory disorders such as rheumatoid arthritis and osteoarthritis. Approximately 40% of older Americans take NSAIDs. Chronic NSAID use carries a risk of peptic ulcer and other gastrointestinal disturbances. This article reviews the diagnosis of medication-induced ulcers based on clinical presentation, laboratory tests, and endoscopic findings to assist the clinician in early diagnosis and appropriate therapy. Risk factors for NSAID-induced ulcers include old age, poor medical status, prior ulcer, alcoholism, smoking, high NSAID dosage, prolonged NSAID use, and concomitant use of other drugs that are gastric irritants, such as alendronate, a bone resorption inhibitor prescribed for osteoporosis. Appropriate treatment options for patients with medication-induced ulcers include dosage reduction, medication substitution, medication withdrawal, antiulcer therapy, and discontinuation of other gastrotoxic drugs. 相似文献
106.
PR Hunziker S Smith M Scherrer-Crosbie N Liel-Cohen RA Levine R Nesbitt SA Benton MH Picard 《Circulation》1999,99(5):1-6
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging. 相似文献
107.
It is conceivable to view the peritoneal cavity as a separate and specialized compartment. Any events, which occur within this compartment are initially compartmentalized, but subsequently produce immense pathophysiological changes in the neighboring spaces and organs, and on the whole body as well. This review will focus on the local and systemic consequences of physical changes within the peritoneal compartment, caused by elevated intra-abdominal pressure and the pneumoperitoneum, which is induced during laparoscopic surgery. Intra-abdominal hypertension is yet another factor to consider in the overall management of the surgical and critically ill. Commonly it is relatively silent but contributing to patients SIRS, organ dysfunction and death. It may mimic sepsis and/or contribute to it. This old-new pathophysiological entity, which has been ignored for so long should be recognized, prevented and treated. 相似文献
108.
Concern is often expressed about the extent of unnecessary surgery performed. The surgical histories of 150 hospital patients, 84% of whom had undergone previous surgery (2.4 procedures each) were investigated. The need for improved surgical statistical data and quality control is emphasized. 相似文献
109.
110.