全文获取类型
收费全文 | 3138221篇 |
免费 | 395732篇 |
国内免费 | 42296篇 |
专业分类
耳鼻咽喉 | 44564篇 |
儿科学 | 94306篇 |
妇产科学 | 82035篇 |
基础医学 | 461747篇 |
口腔科学 | 85546篇 |
临床医学 | 304565篇 |
内科学 | 631855篇 |
皮肤病学 | 63201篇 |
神经病学 | 261172篇 |
特种医学 | 125395篇 |
外国民族医学 | 1129篇 |
外科学 | 478134篇 |
综合类 | 114009篇 |
现状与发展 | 1篇 |
一般理论 | 1173篇 |
预防医学 | 262109篇 |
眼科学 | 84660篇 |
药学 | 264683篇 |
7篇 | |
中国医学 | 52193篇 |
肿瘤学 | 163765篇 |
出版年
2019年 | 34496篇 |
2018年 | 43524篇 |
2017年 | 37496篇 |
2016年 | 38329篇 |
2015年 | 41490篇 |
2014年 | 53923篇 |
2013年 | 75690篇 |
2012年 | 97159篇 |
2011年 | 103393篇 |
2010年 | 68867篇 |
2009年 | 71962篇 |
2008年 | 96671篇 |
2007年 | 98938篇 |
2006年 | 99238篇 |
2005年 | 96882篇 |
2004年 | 95454篇 |
2003年 | 91808篇 |
2002年 | 90361篇 |
2001年 | 143847篇 |
2000年 | 144976篇 |
1999年 | 126930篇 |
1998年 | 42863篇 |
1997年 | 38885篇 |
1996年 | 38423篇 |
1995年 | 37218篇 |
1994年 | 35303篇 |
1993年 | 32773篇 |
1992年 | 101199篇 |
1991年 | 97556篇 |
1990年 | 94048篇 |
1989年 | 90668篇 |
1988年 | 84542篇 |
1987年 | 82973篇 |
1986年 | 78957篇 |
1985年 | 74918篇 |
1984年 | 56748篇 |
1983年 | 48956篇 |
1982年 | 31800篇 |
1981年 | 28291篇 |
1979年 | 53696篇 |
1978年 | 38278篇 |
1977年 | 32961篇 |
1976年 | 30866篇 |
1975年 | 32466篇 |
1974年 | 39475篇 |
1973年 | 37499篇 |
1972年 | 35414篇 |
1971年 | 32472篇 |
1970年 | 30649篇 |
1969年 | 28443篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Jeffrey J. Silbiger 《Echocardiography (Mount Kisco, N.Y.)》2019,36(5):954-957
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR. 相似文献
52.
53.
54.
【摘要】目的 观察川陈皮素对糖尿病肾病大鼠的治疗作用,并从腺苷酸蛋白活化激酶(AMPK)和内皮型一氧化氮酶(eNOS)途径探讨其作用机理。方法 采用高脂高糖饲料喂养+链脲佐菌素(STZ)腹腔注射复制2型糖尿病肾脏损害大鼠模型,模型构建成功后,将其随机分为正常组、模型组、贝那普利干预组以及川陈皮素低、中和高剂量治疗组(n=20)。实验中密切监测大鼠一般情况,治疗期结束后收集尿液检测24h蛋白尿,收集血液检测肾功能指标、抗氧化指标,收集肾脏观察肾脏病理学,同时检测肾脏组织中AMPK及eNOS蛋白和mRNA的表达结果。结果 正常组肾小球正常,无明显病理特征;模型组出现肾小球增大,系膜和肾间质纤维组织增生;贝那普利组和川陈皮素三个剂量组相较于模型组明显减轻。与正常组相比,模型组24h尿蛋白定量、UREA、CREA和MDA明显升高(P<005);SOD和GSH明显降低(P<005),与模型组相比,贝那普利和川陈皮素三个剂量组24h尿蛋白定量、UREA、CREA和MDA明显降低(P<005),SOD和GSH明显升高(P<005)。与正常组相比,模型组p AMPK、AMPK和eNOS蛋白和mRNA表达均明显降低(P<005);与模型组相比,贝那普利组和川陈皮素低、中和高剂量组AMPK和eNOS蛋白和mRNA表达明显升高(P<005)。结论 川陈皮素可保护肾功能,提高血清和肾脏抗氧化指标,同时增加AMPK和eNOS蛋白和mRNA表达,最终保护糖尿病肾脏损害。 相似文献
55.
Breanne E. Kunstler Jill L. Cook Joanne L. Kemp Paul D. O’Halloran Caroline F. Finch 《Journal of Science and Medicine in Sport》2019,22(1):2-10
Objectives
To determine: (i) the behaviour change techniques used by a sample of Australian physiotherapists to promote non-treatment physical activity; and (ii) whether those behaviour change techniques are different to the techniques used to encourage adherence to rehabilitation exercises.Design
Cross-sectional survey.Method
An online self-report survey was advertised to private practice and outpatient physiotherapists treating patients with musculoskeletal conditions. The use of 50 behaviour change techniques were measured using five-point Likert-type scale questions.Results
Four-hundred and eighty-six physiotherapists responded to the survey, with 216 surveys fully completed. Most respondents (85.1%) promoted non-treatment physical activity often or all of the time. Respondents frequently used 29 behaviour change techniques to promote non-treatment physical activity or encourage adherence to rehabilitation exercises. A similar number of behaviour change techniques was frequently used to encourage adherence to rehabilitation exercises (n = 28) and promote non-treatment physical activity (n = 26). Half of the behaviour change techniques included in the survey were frequently used for both promoting non-treatment physical activity and encouraging adherence to rehabilitation exercises (n = 25). Graded tasks was the most, and punishment was the least, frequently reported technique used to promote non-treatment physical activity and encourage adherence to rehabilitation exercises.Conclusions
Respondents reported using similar behaviour change techniques to promote non-treatment physical activity and encourage adherence to rehabilitation exercises. The variability in behaviour change technique use suggests the behaviour the physiotherapist is promoting influences their behaviour change technique choice. Including the frequently-used behaviour change techniques in non-treatment physical activity promotion interventions might improve their efficacy. 相似文献56.
目的 探讨不同年龄阿尔茨海默病(AD)患者ADC值与年龄的相关性。方法 选取30例AD患者(AD组)和年龄与之相匹配的30名志愿者(对照组),按年龄段各分为6个亚组[55~59岁(n=3)、60~64岁(n=4)、65~70岁(n=9)、71~74岁(n=5)、75~80岁(n=6)、>80岁(n=3)],测量双侧海马、红核、尾状核、杏仁体、壳核ADC值,并进行配对t检验、独立样本t检验、单因素方差分析及Pearson相关分析。结果 AD组红核左、右侧ADC值有统计学差异(P=0.022)。AD组不同年龄亚组右侧海马、双侧尾状核、右侧壳核ADC值差异有统计学意义(P均<0.05);2组不同年龄亚组双侧海马、壳核、尾状核ADC值差异有统计学意义(P均<0.05)。AD组右侧海马(r=0.615,P<0.001)、右侧壳核(r=0.653,P=0.001)及双侧尾状核(左侧:r=0.397,P=0.030;右侧:r=0.429,P=0.020)ADC值与年龄呈正相关。结论 AD患者右侧海马和壳核、双侧尾状核ADC值随年龄增加而增大。ADC值可为临床预测和早期诊断AD脑内右侧海马和壳核、双侧尾状核神经退行性病变提供参考。 相似文献
57.
Widder Randolf A. Lappas Alexandra Rennings Corinna Hild Matthias Roessler Gernot F. Dietlein Thomas S. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(11):2581-2581
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild... 相似文献
58.
59.
60.
Alexander E. J. Trevatt David R. Thomson Robert Miller Matthew Colquhoun Akinyemi I. Idowu Shakeel Rahman 《Journal of plastic surgery and hand surgery》2019,53(2):97-104
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia. 相似文献