全文获取类型
收费全文 | 2355篇 |
免费 | 150篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 65篇 |
妇产科学 | 12篇 |
基础医学 | 207篇 |
口腔科学 | 24篇 |
临床医学 | 248篇 |
内科学 | 297篇 |
皮肤病学 | 11篇 |
神经病学 | 133篇 |
特种医学 | 54篇 |
外科学 | 71篇 |
综合类 | 298篇 |
预防医学 | 822篇 |
眼科学 | 10篇 |
药学 | 180篇 |
中国医学 | 61篇 |
肿瘤学 | 26篇 |
出版年
2024年 | 4篇 |
2023年 | 59篇 |
2022年 | 149篇 |
2021年 | 156篇 |
2020年 | 136篇 |
2019年 | 117篇 |
2018年 | 90篇 |
2017年 | 82篇 |
2016年 | 64篇 |
2015年 | 63篇 |
2014年 | 138篇 |
2013年 | 135篇 |
2012年 | 147篇 |
2011年 | 167篇 |
2010年 | 114篇 |
2009年 | 138篇 |
2008年 | 119篇 |
2007年 | 128篇 |
2006年 | 94篇 |
2005年 | 67篇 |
2004年 | 42篇 |
2003年 | 37篇 |
2002年 | 35篇 |
2001年 | 31篇 |
2000年 | 23篇 |
1999年 | 24篇 |
1998年 | 14篇 |
1997年 | 16篇 |
1996年 | 22篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 10篇 |
1992年 | 13篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 1篇 |
排序方式: 共有2529条查询结果,搜索用时 31 毫秒
81.
Sfar S El Heni J Laporte F Braham H Jawed A Amor S Sfar MT Kerkeni A 《Experimental gerontology》2012,47(3):243-249
Micronutrients as well as essential fatty acids are indispensable for the correct functioning of the organism. The risk of disturbance in the associated nutrition and metabolism is expected to increase during ageing. In addition, it seems that trace elements are involved in the fatty acids metabolism. The aim of the present study was then to assess age-related changes in trace elements status and in plasma essential fatty acids composition with an emphasis on the desaturase activity estimation. Two hundred healthy Tunisian subjects (30-85 years old) were recruited and separated into two subgroups: elderly (65-85 years old) and middle-aged (30-60 years old). The findings revealed that plasma zinc and calcium concentrations significantly decreased according to age. The prevalence of zinc deficiency was therefore shown to increase in old age (over 60% of elderly subjects were deficient or at risk of deficiency). No age-related changes were obtained for copper or magnesium status. The Δ6 desaturase, involved in the EFAs conversion, was shown to decrease according to age and to be associated with the plasma zinc level. Since elderly subjects were at risk of nutritional imbalance, it would be interesting to set optimal dietary proportion. This will help to prevent age-associated alterations and diseases for a better and healthy ageing. 相似文献
82.
83.
Ghuncha Firdaus Ateeque Ahmad 《International Journal of Mental Health Promotion, The》2013,15(5):279-288
Urban environment has now been recognized as significant risk factor of depression; however, there remains a gap in the literature regarding specific stressors associated with urbanization. Therefore, the present study is designated to examine the strength of association between urban environment and depression in temporal manner, and to identify significant risk factors. A household survey based on a questionnaire was conducted in 2003 and 2013, covering 1326 and 1965 households, respectively, from 12 wards of Delhi, India, to procure household-level data. Prevalence of depression was measured using the Centre for Epidemiologic Studies Depression Scale. The individual response rate within participating households was 88.3% in 2003, while it was 82.7% in 2013. During the period of study, the percentage of depressed people increased from 30.9% (2003) to 33.4% (2013). At the univariate level, significant confounders that were associated with depression were being female, unmarried and underemployed. The risk of being depressed due to inaccessibility to basic facilities reduced by ? 1.5%, while fear of crime and reducing social support recorded a phenomenal increase of 31.1% and 14.4%, respectively, during the period of study. Within domain analysis, after adjusting for confounding factors, indoor noise pollution (OR 3.04, p < 0.001), overcrowding (OR 2.35, p < 0.001), increasing crime (OR 1.72, p < 0.001), less supportive neighbours (OR 1.16, p < 0.001) and lacking park/playground (OR 1.12, p < 0.001) remained significantly associated with being depressed. This study confirms an association between the urban environment and depression across a range of domains. This study highlights the need to intervene on both physical and social features of urban centres to promote mental well-being. 相似文献
84.
目的 评估正常人动脉顺应性与糖化血红蛋白之间的关联.方法 横断面调查福建沿海地区30岁以上健康人1175例,行肱-踝脉搏波传导速度和糖化血红蛋白等检测,采用单因素分析和Logistic多元回归分析评价糖化血红蛋白与肱-踝脉搏波传导速度相关情况.结果 (1)肱-踝脉搏波传导速度与糖化血红蛋白具有相关性(r=0.147,P<0.05);(2)糖化血红蛋白四分法组间显示,肱-踝脉搏波传导速度在四组间差异有统计学意义(P<0.001);随着糖化血红蛋白水平升高,脉搏波传导速度增快,异常肱-踝脉搏波传导速度的比例升高;异常肱-踝脉搏波传导速度组糖化血红蛋白大于正常肱-踝脉搏波传导速度组(P<0.05);(3) Logistic回归分析显示,年龄、收缩压、舒张压、糖化血红蛋白、尿酸为正常人群肱-踝脉搏波传导速度独立危险因素(均P <0.05),其中糖化血红蛋白比值比最大(OR=2.692,P<0.05).结论 糖化血红蛋白与肱-踝脉搏波传导速度独立相关,提示非糖尿病健康人群中中间高血糖水平参与了大动脉血管壁早期功能或结构性损伤. 相似文献
85.
86.
《Journal of family psychotherapy》2013,24(1-2):235-250
Abstract Members of Florence Kaslow's family of procreation share their insights into the myriad ways in which her professional contributions in family psychology and international psychology have had an impact on their family life. Particular attention is paid to the family life of psychotherapists, healthy family functioning, healthy long-term marriages, sex therapy, military psychology, family business consulting and the use of projective genograms, and international family psychology. 相似文献
87.
Torres-Gallegos I Zavala-Alonso V Patiño-Marín N Martinez-Castañon GA Anusavice K Loyola-Rodríguez JP 《Australian dental journal》2012,57(2):151-156
Background: Dental fluorosis requires aesthetic treatment to improve appearance and etching of enamel surfaces with phosphoric acid is a key step for adhesive restorations. The aim of this study was to evaluate surface roughness and a depth profile in healthy and fluorotic enamel before and after phosphoric acid etching at 15, 30 and 60 seconds. Methods: One hundred and sixty enamel samples from third molars with no fluorosis to severe fluorosis were evaluated by atomic force microscopy. Results: Healthy enamel showed a statistically significant difference (p < 0.05) between mean surface roughness at 15 seconds (180.3 nm), 30 seconds (260.9 nm) and 60 seconds (346.5 nm); depth profiles revealed a significant difference for the 60 second treatment (4240.2 nm). For mild fluorosis, there was a statistically significant difference (p < 0.05) between mean surface roughness for 30 second (307.8 nm) and 60 second (346.6 nm) treatments; differences in depth profiles were statistically significant at 15 seconds (2546.7 nm), 30 seconds (3884.2 nm) and 60 seconds (3612.1 nm). For moderate fluorosis, a statistically significant difference (p < 0.05) was observed for surface roughness for 30 second (324.5 nm) and 60 second (396.6 nm) treatments. Conclusions: Surface roughness and depth profile analyses revealed that the best etching results were obtained at 15 seconds for the no fluorosis and mild fluorosis groups, and at 30 seconds for the moderate fluorosis group. Increasing the etching time for severe fluorosis decreased surface roughness and the depth profile, which suggests less micromechanical enamel retention for adhesive bonding applications. 相似文献
88.
李立明 《中华流行病学杂志》2023,44(1):81-84
我国已快速进入老龄化社会, 人口老龄化及老年人群的健康问题日益突出, 长寿老人作为"健康老人模板", 对其开展健康相关的流行病学研究, 建设健康老龄社会有重要的指导意义。目前长寿老人流行病学研究前瞻性研究仍然较少, 尚需涵盖人口社会学、生活习惯、饮食结构、疾病谱、心理精神状态、医学影像指标、生物标志物、基因等诸多层面的长寿老人队列数据的长期随访收集以及生物样本库的建立完善。本期重点号展示了中国海南百岁老人队列研究基于7年随访数据, 围绕百岁老人全因死亡的风险因素展开的研究成果, 以期为长寿老人流行病学研究的深入和健康老龄化策略的制定提供科学依据。 相似文献
89.
《Joint, bone, spine : revue du rhumatisme》2022,89(4):105370
ObjectivesTo assess the interest of MRI and ultrasonography (US) in identifying early and advanced interphalangeal (IP) OA.MethodsWe conducted a case-control study including patients with symptomatic hand OA (n = 33) and young healthy volunteers (n = 26). Proximal and distal IP joints were graded according to Kellgren and Lawrence (KL) grades. In OA patients, we separated IP joints into 2 groups: “at risk of OA” joints (potential early pre-radiographic OA joints, KL = 0) and OA joints (KL = 2–4). All IP joints from healthy participants were KL = 0 and were considered strictly normal IP joints. Concurrently, synovitis, effusion, erosions, osteophytes, bone marrow lesions, cysts and cartilage space loss were graded by MRI and/or US. We assessed their prevalence, severity and diagnostic performance in hand OA and then compared normal IP joints from healthy participants and “at risk of OA” IP joints from OA patients as well as “at risk of OA” and OA IP joints from OA patients.ResultsThe prevalence and grade of most MRI/US-detected lesions were higher in IP joints from OA patients than healthy participants. Except for osteophyte assessment, MRI seemed more sensitive than US. We found more MRI/US-detected lesions in “at risk of OA” IP joints than normal joints but also in OA than “at risk of OA” joints from OA patients. US appeared both sensitive and specific for detecting osteophytes in joints without radiographic abnormalities.ConclusionsMRI and US give good performance for detecting radiographic and pre-radiographic OA lesions and could be interesting tools to identify early hand OA. 相似文献
90.
Lauren T. Ptomey Felicia L. Steger Jaehoon Lee Debra K. Sullivan Jeannine R. Goetz Jeffery J. Honas Richard A. Washburn Cheryl A. Gibson Joseph E. Donnelly 《Journal of the Academy of Nutrition and Dietetics》2018,118(6):1087-1096