全文获取类型
收费全文 | 47031篇 |
免费 | 5174篇 |
国内免费 | 1401篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 2895篇 |
妇产科学 | 417篇 |
基础医学 | 4055篇 |
口腔科学 | 250篇 |
临床医学 | 4008篇 |
内科学 | 6838篇 |
皮肤病学 | 355篇 |
神经病学 | 1065篇 |
特种医学 | 853篇 |
外国民族医学 | 1篇 |
外科学 | 12535篇 |
综合类 | 7069篇 |
现状与发展 | 4篇 |
一般理论 | 1篇 |
预防医学 | 2759篇 |
眼科学 | 295篇 |
药学 | 3117篇 |
22篇 | |
中国医学 | 6225篇 |
肿瘤学 | 763篇 |
出版年
2024年 | 192篇 |
2023年 | 1093篇 |
2022年 | 1909篇 |
2021年 | 3113篇 |
2020年 | 2418篇 |
2019年 | 2249篇 |
2018年 | 2061篇 |
2017年 | 2191篇 |
2016年 | 2182篇 |
2015年 | 2064篇 |
2014年 | 3388篇 |
2013年 | 3401篇 |
2012年 | 2478篇 |
2011年 | 2727篇 |
2010年 | 2189篇 |
2009年 | 1986篇 |
2008年 | 1922篇 |
2007年 | 1837篇 |
2006年 | 1712篇 |
2005年 | 1437篇 |
2004年 | 1282篇 |
2003年 | 1106篇 |
2002年 | 912篇 |
2001年 | 870篇 |
2000年 | 661篇 |
1999年 | 569篇 |
1998年 | 535篇 |
1997年 | 432篇 |
1996年 | 420篇 |
1995年 | 417篇 |
1994年 | 366篇 |
1993年 | 321篇 |
1992年 | 308篇 |
1991年 | 318篇 |
1990年 | 255篇 |
1989年 | 259篇 |
1988年 | 223篇 |
1987年 | 199篇 |
1986年 | 183篇 |
1985年 | 216篇 |
1984年 | 186篇 |
1983年 | 113篇 |
1982年 | 161篇 |
1981年 | 141篇 |
1980年 | 102篇 |
1979年 | 123篇 |
1978年 | 78篇 |
1977年 | 72篇 |
1976年 | 75篇 |
1975年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion. 相似文献
3.
目的 运用核磁共振弥散张量成像技术(DTI),从皮质脊髓束损伤程度评价的角度,探讨肾虚髓亏证与急性缺血性脑卒中运动功能缺损程度相关性,丰富中风病病机及证候诊断,拓宽缺血性脑卒中的中医药防治思路,为急性缺血性脑卒中肾虚髓亏证患者运动功能损伤程度提供临床依据,强调肾虚髓亏证在急性缺血性脑卒中运动功能损伤中的重要意义。方法 纳入符合诊断标准的90例病例,根据证候分别归入肾虚髓亏组和非肾虚髓亏组,每组各45例。每组患者均给予常规西药治疗。对两组患者入院后行弥散张量成像检测,同时分别于治疗前及治疗后14天,记录两组患者NIHSS评分、改良Barthel指数量表及简化Fugl-Meyer运动功能评分量表评分,比较两组病例发病时的轻重程度及治疗前后两组病例组间的恢复差异。结果 研究显示,治疗前肾虚髓亏组在NIHSS评分方面高于非肾虚髓亏组(P<0.05);治疗前肾虚髓亏组在改良Barthel指数量表及简化Fugl-Meyer运动功能评分方面低于非肾虚髓亏组(P<0.05)。治疗前后NIHSS评分、改良Barthel指数评分及简化Fugl-Meyer运动功能评分改善情况,非肾虚髓亏组要优于肾虚髓亏组(P<0.05)。治疗前两组患者在健侧内囊后肢及大脑脚外侧处FA值及ADC值无明显差异;肾虚髓亏组在患侧内囊后肢及大脑脚外侧处FA值及ADC值均低于非肾虚髓亏组(P<0.05)。相关性分析得出,两组患者患侧内囊后肢FA值与患者治疗前NIHSS评分呈负相关;两组患者患侧内囊后肢FA值与患者改良Barthel指数评分及简化Fugl-Meyer运动功能评分呈正相关;肾虚髓亏组患者患侧内囊后肢FA值与肾虚髓亏证中医证候评分呈负相关。结论 肾虚髓亏是急性缺血性脑卒中运动功能障碍的重要病机。研究结果显示,两组皮质脊髓束损伤程度与神经功能及运动功能损伤存在相关性,且肾虚髓亏组在皮质脊髓束的损伤程度方面与其中医证候评分呈负相关。 相似文献
4.
5.
6.
Martin R. Späth Malte P. Bartram Nicolàs Palacio-Escat K. Johanna R. Hoyer Cedric Debes Fatih Demir Christina B. Schroeter Amrei M. Mandel Franziska Grundmann Giuliano Ciarimboli Andreas Beyer Jayachandran N. Kizhakkedathu Susanne Brodesser Heike Göbel Jan U. Becker Thomas Benzing Bernhard Schermer Martin Höhne Markus M. Rinschen 《Kidney international》2019,95(2):333-349
7.
Jose M. Morales Jose Angel Martinez-Flores Manuel Serrano Maria José Castro Francisco Javier Alfaro Florencio García Miguel Angel Martínez Amado Andrés Esther González Manuel Praga Estela Paz-Artal Antonio Serrano 《Journal of the American Society of Nephrology : JASN》2015,26(3):735-745
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation. 相似文献
8.
9.
10.
Caroline E. Sloan Judy Zhong Dinushika Mohottige Rasheeda Hall Clarissa J. Diamantidis Leight E. Boulware Virginia Wang 《Seminars in dialysis》2020,33(6):440-448
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD. 相似文献