全文获取类型
收费全文 | 1410781篇 |
免费 | 113543篇 |
国内免费 | 3333篇 |
专业分类
耳鼻咽喉 | 18360篇 |
儿科学 | 46573篇 |
妇产科学 | 41061篇 |
基础医学 | 200744篇 |
口腔科学 | 37704篇 |
临床医学 | 126017篇 |
内科学 | 284382篇 |
皮肤病学 | 33366篇 |
神经病学 | 116856篇 |
特种医学 | 53830篇 |
外国民族医学 | 464篇 |
外科学 | 210513篇 |
综合类 | 32790篇 |
现状与发展 | 3篇 |
一般理论 | 489篇 |
预防医学 | 110013篇 |
眼科学 | 31492篇 |
药学 | 98517篇 |
1篇 | |
中国医学 | 3349篇 |
肿瘤学 | 81133篇 |
出版年
2021年 | 10843篇 |
2019年 | 11661篇 |
2018年 | 16568篇 |
2017年 | 12671篇 |
2016年 | 14257篇 |
2015年 | 16008篇 |
2014年 | 22556篇 |
2013年 | 33389篇 |
2012年 | 45371篇 |
2011年 | 47909篇 |
2010年 | 28153篇 |
2009年 | 27050篇 |
2008年 | 44305篇 |
2007年 | 46806篇 |
2006年 | 47381篇 |
2005年 | 45843篇 |
2004年 | 43733篇 |
2003年 | 41679篇 |
2002年 | 40179篇 |
2001年 | 73001篇 |
2000年 | 74528篇 |
1999年 | 61556篇 |
1998年 | 16992篇 |
1997年 | 15437篇 |
1996年 | 15590篇 |
1995年 | 14796篇 |
1994年 | 13404篇 |
1993年 | 12591篇 |
1992年 | 45842篇 |
1991年 | 43483篇 |
1990年 | 41491篇 |
1989年 | 39554篇 |
1988年 | 36181篇 |
1987年 | 35358篇 |
1986年 | 32867篇 |
1985年 | 31285篇 |
1984年 | 23828篇 |
1983年 | 20034篇 |
1982年 | 12214篇 |
1981年 | 10782篇 |
1979年 | 20704篇 |
1978年 | 14578篇 |
1977年 | 12089篇 |
1976年 | 11371篇 |
1975年 | 11621篇 |
1974年 | 13992篇 |
1973年 | 13535篇 |
1972年 | 12635篇 |
1971年 | 11474篇 |
1970年 | 10911篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Jamshid Shirani Jagat Narula William C. Eckelman Navneet Narula Vasken Dilsizian 《Journal of nuclear cardiology》2007,14(1):100-110
Conclusions Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed
for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral
antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization
of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify
the likelihood of adverse and favorable remodeling.74 相似文献
994.
995.
996.
Cytokines play a pivotal role in the pathogenesis of degenerative joint disease but also in inflammatory conditions as well as osteoarthritis (OA) and rheumatoid arthritis (RA). A key role is attributed to interleukin-1 and tumor necrosis factor-α. Certain cytokines that can inhibit the activity of catabolic cytokines have great therapeutic potential and are currently being investigated in numerous clinical studies. Available scientific findings indicate that proinflammatory cytokines stimulate cartilage breakdown and blockade of these cytokines can protect the cartilage. 相似文献
997.
Lesley C Dinwiddie 《Nephrology nursing journal》2004,31(6):653-60, 671; quiz 661-2
Vascular access is the leading cause of morbidity in the hemodialysis patient population. Arteriovenous fistulas (AVFs) have the lowest complication rate while catheters have the highest. Though significant effort is being made to increase the number of AVFs and lower the number of catheters, annual data show that the number of catheters is increasing. To improve vascular access-related patient outcomes, catheter dysfunction needs to be managed by a vascular access team using the CQI process that begins with a comprehensive algorithm for treatment. 相似文献
998.
999.
Claire-Jehanne Dubouloz Diane Laporte Martha Hall Brenda Ashe C Douglas Smith 《The American journal of occupational therapy》2004,58(4):398-407
The purpose of this qualitative study was to examine the process of transformation of personal beliefs, values, feelings, and knowledge (meaning perspectives) underlying occupational change in a small group of clients with rheumatoid arthritis during home-based rehabilitation. A grounded theory approach used to collect and analyze data concurrently included: (1) a sample of five adult clients diagnosed with rheumatoid arthritis in occupational therapy, (2) data collection through 28 semi-directed interviews, and (3) data analysis using the constant comparison method. The study identified meaning perspectives of these clients with rheumatoid arthritis and explored the transformation of perspectives related to the modification of occupational performance. The study suggests that the exploration of meaning perspective transformation by clients and therapists could be a potential part of rehabilitation intervention. 相似文献
1000.
Evagelos N Liberopoulos Eleni Papavasiliou George A Miltiadous Marios Cariolou Kostas C Siamopoulos Alexandros D Tselepis Moses S Elisaf 《Peritoneal dialysis international》2004,24(6):580-589
OBJECTIVE: The more atherogenic lipid profile seen in peritoneal dialysis (PD) patients cannot fully explain the increased incidence of atherosclerosis in this population. Oxidative modification of low-density lipoproteins (LDL) is considered to play a central role in the atherogenic process, whereas high-density lipoprotein (HDL) protects LDL from oxidation. On the other hand, it has been suggested that the LDL and HDL of PD patients are more resistant to oxidation than those of control subjects, while PD-HDL equally protects LDL from oxidation compared to control-HDL. Two HDL-associated enzymes have been shown to protect both LDL and HDL from oxidation: paraoxonase (PON1) and HDL-associated platelet-activating factor acetylhydrolase (HDL-PAF-AH). Furthermore, low PON1 activity and high total plasma PAF-AH concentration, which represents mainly the LDL-associated enzyme, have been shown to be independent risk factors for coronary artery events in the general population. However, there are limited data regarding possible alterations of these enzymes in PD patients. The aim of our study was to examine the possible alterations of PON1 and PAF-AH activities in patients undergoing PD. DESIGN: A cross-sectional study. SETTING: A university medical center. PARTICIPANTS: 56 PD patients of Caucasian origin and 86 matched controls were studied. MEASUREMENTS: In all subjects, serum PON1 activity toward paraoxon (paraoxonase) and phenylacetate (arylesterase), as well as total serum and HDL-PAF-AH activities were measured; PON1 genetic polymorphisms known to influence PON1 activity (Q192R and M55L) were determined. RESULTS: The PD patients exhibited significantly increased serum PON1 (paraoxonase) and PON1 (arylesterase) activities compared to controls, regardless of the PON1 polymorphisms or the levels of HDL cholesterol. Additionally, PD patients had significantly elevated activities of total serum PAF-AH and HDL-PAF-AH, independently of the levels of LDL or HDL cholesterol. The ratio of HDL-PAF-AH/ total PAF-AH, which has recently been suggested to be a potential marker of atherogenicity, was decreased in these patients compared to controls. Moreover, no difference in the prevalence of PON1 polymorphisms between PD patients and controls was found. CONCLUSION: The elevated activities of PON1 and HDL-PAF-AH could explain the increased resistance of PD-HDL to oxidation; the higher activity of total PAF-AH and the decreased HDL-PAF-AH/ total PAF-AH ratio could contribute to the increased incidence of atherosclerosis in these patients. 相似文献