全文获取类型
收费全文 | 8562篇 |
免费 | 525篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 126篇 |
儿科学 | 264篇 |
妇产科学 | 264篇 |
基础医学 | 879篇 |
口腔科学 | 139篇 |
临床医学 | 781篇 |
内科学 | 2238篇 |
皮肤病学 | 81篇 |
神经病学 | 838篇 |
特种医学 | 327篇 |
外科学 | 947篇 |
综合类 | 99篇 |
一般理论 | 6篇 |
预防医学 | 987篇 |
眼科学 | 157篇 |
药学 | 562篇 |
中国医学 | 3篇 |
肿瘤学 | 415篇 |
出版年
2024年 | 10篇 |
2023年 | 35篇 |
2022年 | 58篇 |
2021年 | 174篇 |
2020年 | 84篇 |
2019年 | 167篇 |
2018年 | 190篇 |
2017年 | 159篇 |
2016年 | 146篇 |
2015年 | 170篇 |
2014年 | 279篇 |
2013年 | 391篇 |
2012年 | 631篇 |
2011年 | 688篇 |
2010年 | 377篇 |
2009年 | 372篇 |
2008年 | 567篇 |
2007年 | 686篇 |
2006年 | 640篇 |
2005年 | 613篇 |
2004年 | 576篇 |
2003年 | 527篇 |
2002年 | 463篇 |
2001年 | 103篇 |
2000年 | 66篇 |
1999年 | 85篇 |
1998年 | 104篇 |
1997年 | 77篇 |
1996年 | 60篇 |
1995年 | 69篇 |
1994年 | 48篇 |
1993年 | 46篇 |
1992年 | 48篇 |
1991年 | 29篇 |
1990年 | 37篇 |
1989年 | 60篇 |
1988年 | 35篇 |
1987年 | 24篇 |
1986年 | 21篇 |
1985年 | 17篇 |
1984年 | 30篇 |
1983年 | 20篇 |
1982年 | 23篇 |
1981年 | 18篇 |
1980年 | 16篇 |
1979年 | 7篇 |
1978年 | 14篇 |
1977年 | 11篇 |
1976年 | 9篇 |
1971年 | 6篇 |
排序方式: 共有9113条查询结果,搜索用时 15 毫秒
101.
Ear,nose and throat disorders in children with Down syndrome 总被引:1,自引:0,他引:1
OBJECTIVE: To document the reasons for which children with Down syndrome were referred to a pediatric otolaryngology practice, the underlying causes for these referrals, and the complications of routine surgical therapy. STUDY DESIGN: The study is a retrospective review of children referred to the Pediatric Otolaryngology Clinic at the University of New Mexico Health Sciences Center (Albuquerque, NM) during a period of 2.5 years. METHODS: Data were collected on 55 parameters related to ethnicity, demographics, diagnosis, surgical therapy, complications, and systemic comorbid conditions. RESULTS: The ethnicity of the study population was predominantly Hispanic or Latino (62%). The majority of children (76%) were referred for upper airway obstruction. Obstructive sleep apnea and laryngomalacia were the most common disorders in these children. An otological disorder was diagnosed in 70% of the children. Complications occurred after 27% of procedures for insertion of pressure equalization (PE) tubes to treat recurrent otitis media. Systemic comorbid conditions were present in 93% of the children, and the most common was gastroesophageal reflux disease. CONCLUSIONS: Obstructive sleep apnea and laryngomalacia were the most common reasons for referral of children with Down syndrome. Routine surgical procedures that required general anesthesia caused complications that are not common in other children. Treatment for systemic comorbid conditions should be considered as a component of therapy for otolaryngological disorders in children with Down syndrome. 相似文献
102.
Systemic vasculitides can cause retinal vascular pathology, including cotton-wool spots, retinal hemorrhages, vascular occlusion, and capillary nonperfusion. Two main causes of visual decline include macular edema and retinal neovascularization. Presumably, both of these complications are caused by increased intraocular levels of vascular growth and permeability factors. We report a patient with occlusive retinal vasculitis associated with mixed connective tissue disease who was treated with intravitreal bevacizumab for chronic macular edema. One month after treatment, visual acuity improved from 20/80 to 20/60, and foveal thickness decreased from 543 microns to 306 microns. This effect persisted for at least 3 months after treatment. No complications, including increased retinal ischemia, were observed. 相似文献
103.
PURPOSE: Lutein and zeaxanthin are largely transported in plasma by high-density lipoprotein (HDL). The Wisconsin hypoalpha mutant (WHAM) chicken has a recessive sex-linked mutation in the ABCA1 transporter gene that results in a severe deficiency of HDL. In this study, the transport and tissue distribution of lutein and zeaxanthin were examined in newly hatched and 28-day-old WHAM chicks compared with control chicks. METHODS: One-day-old WHAM and control chicks were randomized to be fed a high-lutein or a control diet for 28 days. The plasma and tissues were analyzed for lutein, zeaxanthin, and lipoproteins on days 1 and 28. RESULTS: The WHAM chicks had very low plasma levels of HDL cholesterol (5.3% of normal). They also had very low concentrations of lutein in the plasma and all other tissues compared with control chicks. The plasma and retina were only 9% and 6% of control levels (P < 0.01), respectively. Zeaxanthin levels were similarly low (9% of control, P < 0.01). The high-lutein diet increased the content of lutein in the plasma and tissues of control chicks (P < 0.01). In contrast, in WHAM chicks, lutein increased greatly in the plasma, liver, and heart, but little in the retina (6% of control). CONCLUSIONS: HDL deficiency in the WHAM chicks was associated with a deficiency of lutein and zeaxanthin in the tissues, especially in the retina. The high-lutein diet increased the lutein content of some tissues via LDL and VLDL transport, but retinal lutein remained very low. These data support the prime role of HDL as the specific transporter of lutein and zeaxanthin into the retina. The WHAM chick provides an excellent model for the study of the role of HDL in the retinal uptake of lutein and zeaxanthin. 相似文献
104.
Schoofs MW van der Klift M Hofman A de Laet CE Herings RM Stijnen T Pols HA Stricker BH 《Annals of internal medicine》2003,139(6):476-482
Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. 相似文献
105.
Incidence of thrombotic stent occlusion during the first three months after sirolimus-eluting stent implantation in 500 consecutive patients 总被引:6,自引:0,他引:6
Regar E Lemos PA Saia F Degertekin M Tanabe K Lee CH Arampatzis CA Hoye A Sianos G de Feyter P van der Giessen WJ Smits PC van Domburg RT Serruys PW 《The American journal of cardiology》2004,93(10):1271-1275
Sirolimus-eluting stents have been used in our institution for all percutaneous interventions, without clinical or anatomic exclusion criteria, as part of the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital registry. We analyzed the incidence of (sub)acute stent thrombosis after sirolimus-eluting stent implantation in an unselected population of 510 consecutive patients. At 3-month follow-up, (sub)acute stent thrombosis was diagnosed in 2 patients (0.4%) 6 hours and 11 days after the procedure, respectively. These cases occurred in diabetic women with complex coronary lesions. Intravascular ultrasound examination showed inadequate stent expansion and uncovered distal dissection as possible mechanical explanations for the thrombosis. 相似文献
106.
107.
Davis MA Landesman R Tadmor B Hopmeier M Shenhar G Barker T Pozner CN Binstadt ES Nelson S Look R Shubina M Walls RM 《Annals of emergency medicine》2008,51(4):420-5, 425.e1-5
108.
109.
110.
Ebenezer Oni Oluseye Ogunmoroti Norrina Allen Mouaz H. A-Mallah Ron Blankstein Seth S. Martin Irfan Zeb Mary Cushman Parag H. Joshi Matthew J. Budoff Michael J. Blaha Roger S. Blumenthal Emir Veledar Khurram Nasir 《The American journal of medicine》2021,134(4):519-525
BackgroundThe American Heart Association (AHA) has defined Life's Simple 7 (LS7) as a measure of overall cardiovascular health . Nonalcoholic fatty liver disease (NAFLD) has been involved as a risk factor for cardiovascular disease. We evaluated the association between LS7 and NAFLD.MethodsWe evaluated participants form the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Cardiovascular health score was calculated from the Life's Simple 7 metrics. A score of 0-8 was considered inadequate, 9-10 average, and 11-14 optimal. NAFLD was defined using noncontrast cardiac computed tomography (CT) and a liver/spleen attenuation ratio (L/S) < 1. Multivariable regression were performed to evaluate the association.ResultsOur cross-sectional analysis of 3901 participants showed 19% (n = 747) had optimal cardiovascular health, 33% (n = 1270) had average, and 48% (n = 1884) had inadequate. White participants were most likely to have an optimal score (51%, n = 378), whereas African American participants had the lowest proportion with optimal scores (16%, n = 120; P < 0.001). The overall prevalence of NAFLD was 18% with a distribution of 7%, 14%, and 25% in the optimal, average, and inadequate score categories, respectively (P < 0.001). Adjusted for risk factors, average and optimal health categories had lower odds of NAFLD compared to those with inadequate scores: odds ratio for average, 0.44 (95% confidence interval 0.36-0.54); optimal, odds ratio 0.19 (95% confidence interval 0.14-0.26). This association was similar across gender, race and age groups.ConclusionA more favorable cardiovascular health score was associated with a lower prevalence of NAFLD. This study may suggest a potential of Life's Simple 7 in the prevention of liver disease. 相似文献