全文获取类型
收费全文 | 28224篇 |
免费 | 1701篇 |
国内免费 | 205篇 |
专业分类
耳鼻咽喉 | 279篇 |
儿科学 | 669篇 |
妇产科学 | 679篇 |
基础医学 | 3288篇 |
口腔科学 | 992篇 |
临床医学 | 2606篇 |
内科学 | 6185篇 |
皮肤病学 | 565篇 |
神经病学 | 1563篇 |
特种医学 | 738篇 |
外国民族医学 | 6篇 |
外科学 | 3867篇 |
综合类 | 766篇 |
一般理论 | 21篇 |
预防医学 | 2200篇 |
眼科学 | 1026篇 |
药学 | 2681篇 |
中国医学 | 306篇 |
肿瘤学 | 1693篇 |
出版年
2024年 | 38篇 |
2023年 | 369篇 |
2022年 | 993篇 |
2021年 | 1489篇 |
2020年 | 983篇 |
2019年 | 1212篇 |
2018年 | 1404篇 |
2017年 | 993篇 |
2016年 | 1051篇 |
2015年 | 1025篇 |
2014年 | 1444篇 |
2013年 | 1697篇 |
2012年 | 2323篇 |
2011年 | 2401篇 |
2010年 | 1400篇 |
2009年 | 1083篇 |
2008年 | 1636篇 |
2007年 | 1527篇 |
2006年 | 1266篇 |
2005年 | 1131篇 |
2004年 | 935篇 |
2003年 | 775篇 |
2002年 | 686篇 |
2001年 | 198篇 |
2000年 | 193篇 |
1999年 | 201篇 |
1998年 | 116篇 |
1997年 | 86篇 |
1996年 | 89篇 |
1995年 | 82篇 |
1994年 | 66篇 |
1993年 | 63篇 |
1992年 | 95篇 |
1991年 | 82篇 |
1990年 | 98篇 |
1989年 | 84篇 |
1988年 | 86篇 |
1987年 | 76篇 |
1986年 | 75篇 |
1985年 | 57篇 |
1984年 | 59篇 |
1983年 | 41篇 |
1982年 | 39篇 |
1981年 | 25篇 |
1980年 | 36篇 |
1979年 | 43篇 |
1977年 | 33篇 |
1976年 | 33篇 |
1974年 | 23篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Arthur J. Matas Raja Kandaswamy Kristen J. Gillingham Lois McHugh Hassan Ibrahim Bertram Kasiske Abhinav Humar 《American journal of transplantation》2005,5(10):2473-2478
Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good. 相似文献
52.
Mohammad Khalid Jamal M.D. Eric J. DeMaria M.D. Jason M. Johnson D.O. Brennan J. Carmody M.D. Luke G. Wolfe M.S. John M. Kellum M.D. Jill G. Meador R.N. 《Surgery for obesity and related diseases》2005,1(6):655-516
BACKGROUND: We hypothesized that major co-morbidities affect survival and complications after gastric bypass. METHODS: A total of 1465 patients undergoing laparoscopic and open gastric bypass between 1995 and 2002 were studied. Patients with a body mass index >or= 35 kg/m(2) and major co-morbidities (group 1, n = 1045) were compared with patients with a body mass index >or= 40 kg/m(2) with minor/no co-morbidities (group 2, n = 420). RESULTS: Group 1 patients were older (43 versus 36 years, P < 0.001) and had a greater BMI (53 versus 50 kg/m(2), P < 0.001). Early postoperative complications were greater in group 1 than in group 2 and included leaks (4.1% versus 1.2%, P < 0.0032) and wound infections (3.9% versus 1.4%, P < 0.0133). Procedure-related mortality in the series was 1.7%. Mortality was 10-fold greater in group 1 (2.3% versus 0.2%, P < 0.0032). The incidence of small bowel obstruction, incisional hernia, and pulmonary embolism was similar in the two groups. Excess weight loss was significantly greater in group 2 (68% versus 62%, P < 0.001) at 1 year. Resolution of group 1 co-morbidities was great, including hypertension in 62%, diabetes in 75%, venous stasis disease in 96%, and pseudotumor cerebri in 98%. CONCLUSION: Outcomes analysis of obesity surgery requires risk stratification. The very low mortality rates in published studies are likely explained by surgical treatment of low-risk patients with minor co-morbidities, such as those seen in group 2. However, despite the increased perioperative risk, the group 1 patients (with major co-morbidities) demonstrated dramatic resolution of their co-morbid conditions, justifying the decision to go forward with surgery. The data support a radical change in treatment philosophy in which morbidly obese individuals should be offered bariatric surgery before major co-morbid conditions develop as a strategy to decrease the operative risk. 相似文献
53.
Omidvari Shapour MD Nezakatgoo Nosrat MD † Ahmadloo Niloofar MD Mohammadianpanah Mohammad MD Mosalaei Ahmad MD 《Dermatologic surgery》2005,31(5):499-501
BACKGROUND: Hemangioma is the most common tumor of infancy. Although it has a basically benign nature and usually spontaneously regresses, a small percentage (5%) have complications that need treatment. Many different therapeutic modalities can be used in this tumor. OBJECTIVE: To investigate the effect of a new method of treatment (intralesional bleomycin injection) in complicated hemangiomas. MATERIALS AND METHODS: In the Department of Radiation Oncology at Nemazee Hospital in Shiraz, Iran, from April 1992 to October 1998, 32 patients with complicated hemangioma were treated with four to six courses of direct injection of bleomycin into the lesion. RESULTS: After a minimum follow-up of 6 years, there was 70 to 100% regression in 18 patients, 50 to 70% in 7 cases, and less than 50% reduction in 7 patients. CONCLUSION: Intralesional injection of bleomycin is an easy, safe, and effective therapeutic modality in complicated cutaneous hemangiomas. 相似文献
54.
Chris Fussman David Todem Johannes Forster Hassan Arshad Radvan Urbanek Wilfried Karmaus 《The Journal of asthma》2007,44(2):99-105
The effect of cow's milk consumption on childhood asthma has been debated for several years. This study attempts to provide further insight into this association through the use of a longitudinal study design. Newborns from parents with atopic history were recruited from Germany, Austria, and England (n = 696). For five repeated ascertainments, information was collected on cow's milk exposure, incidence of doctor-diagnosed asthma, and confounders. Generalized estimation equations, incorporating different models (concurrent, delayed, combined, and reverse causation), were used to determine this association. No association between cow's milk consumption and childhood asthma was found for the concurrent effects model (OR = 0.81, 95% confidence interval [CI]: 0.55, 1.20). In the delayed effects model, the direction of the association varied with time of follow-up. Thus, we stratified by period, which resulted in a significant protective delayed effect at 36 months (OR = 0.18, 95% CI = 0.06, 0.49). However, reverse causation negated this finding since the presence of asthma in prior months led to a reduction in further exposure to cow's milk (OR = 0.40, 95% CI = 0.16, 0.99). Hence, cow's milk consumption does not protect against childhood asthma. The apparent protection of cow's milk against asthma may result from parents of asthmatic children avoiding cow's milk, rather than actual prophylaxis. 相似文献
55.
56.
A. J. Pijl K. A. Solen† S. F. Mohammad R. Monson† L. S. Yu J. M. T. van Griensven D. B. Olsen W. J. Kolff 《Artificial organs》1990,14(2):125-129
Device-induced thrombogenesis was studied in an in vitro model using human blood circulated through an artificial ventricle. A new constant pressure filtration technique was used to detect circulating microemboli, the activated partial thromboplastin time (APTT) test was used to monitor the blood for the presence of anticoagulant activity of heparin, and hemolysis was quantified by measuring the plasma free hemoglobin level. Circulation of blood through a 20-ml stroke volume pneumatically driven ventricle for 6-9 h resulted in a significant reduction of APTT, indicating the loss of the anticoagulant effect of heparin. Microemboli concentration was minimal until the APTT decreased below 125 s, at which time the microemboli concentration increased rapidly. This was presumed to be due to the formation of thrombi following a decrease in heparin activity. A significant increase in hemolysis was also noted when blood was pumped. None of these changes was noted in the nonpumped control blood. Spontaneous loss of heparin activity in blood circulated by a pneumatically driven pump may have clinical implications and may help understanding of the problems associated with device-induced thrombogenesis. 相似文献
57.
58.
59.
60.
Background Germinal matrix and intraventricular hemorrhage (GMH/IVH) is a known complication occurring in the first week of life in preterm neonates. However, the precise time of its occurrence and the ideal time to perform diagnostic imaging studies remain controversial. The purpose of this paper is to address these two issues in our patient population to allocate our resources to those at highest risk.Materials and methods This study included 282 premature newborns (under 37 weeks of gestation) that were admitted to our neonate ICU in a year’s time and screened for GMH/IVH. They were grouped in four categories according to their weight at birth, and according to their gestational age. All patients had a daily cranial ultrasound during the first week. It was then repeated once in the second week and once in the third.Results We found that the incidence of GMH/IVH among preterm neonates was 44.68%. It was inversely related to the weight and the age of the newborn. The onset of bleeding coordinated with the occurrence of hypoxia and respiratory distress requiring mechanical ventilation. The majorities occurred in the first 7 days of life; they were mostly grade I and II according to the Papule classification and silent for the most part. Complications were present in 41% of the survivors. 相似文献