全文获取类型
收费全文 | 1381篇 |
免费 | 119篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 27篇 |
妇产科学 | 20篇 |
基础医学 | 110篇 |
口腔科学 | 38篇 |
临床医学 | 145篇 |
内科学 | 182篇 |
皮肤病学 | 6篇 |
神经病学 | 72篇 |
特种医学 | 108篇 |
外科学 | 406篇 |
综合类 | 50篇 |
预防医学 | 100篇 |
眼科学 | 12篇 |
药学 | 129篇 |
中国医学 | 1篇 |
肿瘤学 | 85篇 |
出版年
2022年 | 11篇 |
2021年 | 28篇 |
2020年 | 16篇 |
2019年 | 19篇 |
2018年 | 23篇 |
2017年 | 18篇 |
2016年 | 16篇 |
2015年 | 46篇 |
2014年 | 42篇 |
2013年 | 65篇 |
2012年 | 57篇 |
2011年 | 56篇 |
2010年 | 48篇 |
2009年 | 36篇 |
2008年 | 52篇 |
2007年 | 48篇 |
2006年 | 55篇 |
2005年 | 62篇 |
2004年 | 50篇 |
2003年 | 47篇 |
2002年 | 38篇 |
2001年 | 34篇 |
2000年 | 38篇 |
1999年 | 32篇 |
1998年 | 27篇 |
1997年 | 28篇 |
1996年 | 26篇 |
1995年 | 20篇 |
1994年 | 18篇 |
1993年 | 19篇 |
1992年 | 12篇 |
1991年 | 23篇 |
1990年 | 24篇 |
1989年 | 32篇 |
1988年 | 20篇 |
1987年 | 26篇 |
1986年 | 17篇 |
1985年 | 13篇 |
1984年 | 24篇 |
1983年 | 15篇 |
1982年 | 13篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 12篇 |
1976年 | 13篇 |
1975年 | 12篇 |
1974年 | 11篇 |
1972年 | 13篇 |
1968年 | 11篇 |
1966年 | 11篇 |
排序方式: 共有1504条查询结果,搜索用时 15 毫秒
1.
2.
T E Dolmage T K Waddell F Maltais G H Guyatt T R J Todd S Keshavjee S van Rooy B Krip P LeBlanc R S Goldstein 《The European respiratory journal》2004,23(2):269-274
Although the influence of lung volume reduction surgery (LVRS) on incremental- and constant-power exercise is important in the evaluation of this procedure for patients with chronic obstructive pulmonary disease (COPD), it is rarely reported even in large randomised controlled trials. This report describes 39 patients with severe COPD ((mean +/- SE) forced expiratory volume in one second 32 +/- 2% pred, functional residual capacity 195 +/- 6% pred) who participated in a randomised controlled trial of LVRS and who completed incremental exercise tests at 6 months as well as endurance tests (constant power of 25 +/- 1 W) at 3, 9 and 12 months. Peak oxygen uptake (V'O2,pk) was similar between the treatment (n = 19) and control groups (n = 20) at baseline. After LVRS, the treatment group had a significantly greater V'O2,pk (mean difference (95% CI) 1.28 (0.07-2.50) mL x kg x min(-1)) and power (13 (6-20) W). The treatment group achieved a significantly greater minute ventilation (7.1 (2.9-11.3) L x min(-1)) with a greater tidal volume (0.16 (0.04-0.28) L). Baseline endurance was similar between groups. After surgery, there were significant between-group differences in endurance time, which were maintained at 12 months (7.3 (3.9-10.8) min). Lung volume reduction surgery is associated with an increase in exercise capacity and endurance, as compared with conventional medical treatment. 相似文献
3.
4.
James P. Waddell 《Canadian journal of surgery》2007,50(1):4-5
5.
James P. Waddell 《Canadian journal of surgery》1996,39(5):354-355
The objectives of this study were to assess trends in referral patterns for joint replacements (JRs) in Ontario between the fiscal year 1988/89 and the fiscal year 1993/94; to assess the redistribution of financial resources if services were provided to residents in the region where they reside; and to estimate the financial implications of the devolution of primary JRs from tertiary-care hospitals to community hospitals. Despite rapid growth in the provision of JRs, there was no significant change in their regional distribution. Community hospitals have increased their share of JRs at the expense of teaching hospitals. For hospitals located in Central east Ontario, the cost of providing JRs to nonresidents increased from $5.9 million in 1988/89 to $8.3 million in 1993/94. Devolution of primary JRs requires a minimum reallocation sum of $25.1 million, with potential cost savings of $4.3 million. Many obstacles limit the devolution and local provision of health care services, including modifications to referral patterns and the availability of provider expertise, especially when a substantial redistribution of resources is required. Better clinical data to evaluate outcomes and better patient-specific costing data are required. Devolution of services should be addressed in the context of appropriate institutional compensation for medical education. 相似文献
6.
7.
8.
9.
H. Kaneda T. K. Waddell M. de Perrot X.-H. Bai C. Gutierrez T. Arenovich C. Chaparro M. Liu S. Keshavjee 《American journal of transplantation》2006,6(3):544-551
While current donor selection with clinical findings is generally effective, the imprecise nature of the assessment forces clinicians to remain on the conservative side. A reliable biological marker would assist donor selection and would improve donor organ utilization. We collected biopsies from 169 donor lungs before implantation. Expression levels of IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma and IL-1beta were measured by quantitative real-time RT-PCR (qRT-PCR). Seventeen cases died within 30 days after transplantation. No donor factor was significantly associated with 30-day mortality. Univariate analysis of the 84 cases for development of the prediction model showed that IL-6, IL-8, TNF-alpha and IL-1beta were risk factors for mortality and IL-10 and IFN-gamma were protective factors. We analyzed the cytokine expression ratios of risk to protective cytokines. A stepwise logistic regression for 30-day mortality demonstrated that a model containing the ratio of IL-6/IL-10 was the most predictive (p = 0.0013). When applied to the remaining 85 cases for validation, the test of model fit was significant (p = 0.039). Using the cytokine ratio, we were able to define three risk groups with striking differences in survival (p = 0.0003). Multi-cytokine analysis of the donor lung graft with qRT-PCR shows significant promise as a strategy to biologically evaluate the donor lung prior to implantation. 相似文献
10.
Cristiano Feijó Andrade Thomas K. Waddell Shaf Keshavjee Mingyao Liu 《American journal of transplantation》2005,5(5):969-975
Traditionally, the recognition and tolerance of transplanted grafts has been considered to be within the realm of the adaptive immune system. Innate immunity, on the other hand, as the first line of host defense, plays a role in fighting against invading microorganisms. Recently, with the discovery of the Toll-like receptors (TLRs), the role of innate immune responses in the control of adaptive immunity has become a new area of interest. Emerging evidence suggests that in addition to responding to pathogen-associated molecular patterns of microorganisms, TLRs can be activated by endogenous ligands, expressed by mammalian cells. These 'danger signals' may participate in ischemia-reperfusion related organ damage and subsequently influence function and survival of transplanted grafts. Furthermore, it has been suggested that adaptive immune responses can enhance the acute inflammatory responses controlled by innate immunity in organ transplantation. This review addresses the potential involvement of TLRs in different stages of organ transplantation. Intriguing and controversial findings are presented and discussed in order to stimulate more attention to this emerging and potentially important area of research in organ transplantation. 相似文献