全文获取类型
收费全文 | 71321篇 |
免费 | 9040篇 |
国内免费 | 370篇 |
专业分类
耳鼻咽喉 | 1245篇 |
儿科学 | 1785篇 |
妇产科学 | 1906篇 |
基础医学 | 7337篇 |
口腔科学 | 4138篇 |
临床医学 | 9679篇 |
内科学 | 15947篇 |
皮肤病学 | 1250篇 |
神经病学 | 6782篇 |
特种医学 | 2727篇 |
外科学 | 10027篇 |
综合类 | 379篇 |
现状与发展 | 12篇 |
一般理论 | 44篇 |
预防医学 | 6287篇 |
眼科学 | 1123篇 |
药学 | 3623篇 |
1篇 | |
中国医学 | 65篇 |
肿瘤学 | 6374篇 |
出版年
2024年 | 192篇 |
2023年 | 1408篇 |
2022年 | 980篇 |
2021年 | 1764篇 |
2020年 | 1945篇 |
2019年 | 1452篇 |
2018年 | 2501篇 |
2017年 | 2338篇 |
2016年 | 2738篇 |
2015年 | 2852篇 |
2014年 | 3676篇 |
2013年 | 4843篇 |
2012年 | 4529篇 |
2011年 | 4681篇 |
2010年 | 3695篇 |
2009年 | 4072篇 |
2008年 | 4003篇 |
2007年 | 4060篇 |
2006年 | 3826篇 |
2005年 | 3697篇 |
2004年 | 3306篇 |
2003年 | 3071篇 |
2002年 | 2803篇 |
2001年 | 796篇 |
2000年 | 615篇 |
1999年 | 853篇 |
1998年 | 1056篇 |
1997年 | 935篇 |
1996年 | 936篇 |
1995年 | 729篇 |
1994年 | 603篇 |
1993年 | 566篇 |
1992年 | 406篇 |
1991年 | 379篇 |
1990年 | 343篇 |
1989年 | 360篇 |
1988年 | 317篇 |
1987年 | 292篇 |
1986年 | 275篇 |
1985年 | 302篇 |
1984年 | 256篇 |
1983年 | 255篇 |
1982年 | 274篇 |
1981年 | 226篇 |
1980年 | 184篇 |
1979年 | 144篇 |
1978年 | 154篇 |
1977年 | 174篇 |
1976年 | 125篇 |
1975年 | 134篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Marieke Peeters Ludo Verhoeven Jan de Moor Hans van Balkom 《Research in developmental disabilities》2009,30(4):712-726
The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech Perception, Speech Production and Nonverbal Reasoning were considered reading precursors. Children with cerebral palsy lag behind on all reading precursors at the beginning of the second year of kindergarten. For the children without disabilities, early reading skills in Grade 1 were best predicted by Phonological Awareness and Phonological STM while Speech Production was the most important predictor of early reading success for the children with cerebral palsy, followed by Phonological Awareness and Speech Perception. Furthermore, for children with cerebral palsy, Speech Production appears to dominate reading development, as Speech Production measured at the beginning of the second year of kindergarten was strongly predictive of all other reading precursors measured at the end of the second year of kindergarten. The results of this study reveal that children with cerebral palsy with additional speech impairments are at risk for limited literacy development. Clinical implications are discussed. 相似文献
82.
83.
84.
85.
86.
Antihypertensive Combination Therapy: Optimizing Blood Pressure Control and Cardiovascular Risk Reduction 总被引:1,自引:0,他引:1
Treating hypertension reduces the rates of myocardial infarction, stroke, and renal disease; however, clinical trial experience suggests that monotherapy is not likely to be successful for achieving goal blood pressure (BP) levels in many hypertensive patients. In multiple recent clinical trials including various subsets of hypertensive patients, the achievement of BP goal has typically required the combination of 2 or more medications, particularly in patients with BP levels >160/100 mm Hg. When initiating combination therapy for hypertension, careful consideration must be given to the choice of medication. Clinical trial evidence has shown the efficacy of various combinations of angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, and diuretics in reducing BP and cardiovascular risk. Ongoing trials should provide additional guidance on the optimal choice of combination regimens in specific clinical settings. 相似文献
87.
Color Stability of Dry Earth Pigmented Maxillofacial Silicone A-2186 Subjected to Microwave Energy Exposure 总被引:2,自引:0,他引:2
Sudarat Kiat-amnuay DDS MS ; Dennis A. Johnston PhD ; John M. Powers PhD ; Rhonda F. Jacob DDS MS 《Journal of prosthodontics》2005,14(2):91-96
PURPOSE: The purpose of this study was to measure spectrophotometrically the color stability of pigmented A-2186 silicone maxillofacial elastomer with 10% by volume of titanium white dry earth opacifier before and after exposure to microwave energy over a simulated 1.5-year period of microwave sterilization. Materials AND METHODS: A-2186 silicone elastomer opacified with titanium white dry earth pigment, pigmented with 5 cosmetic dry earth pigment colors [no pigment (control) group (Pc), red (Pr), yellow ochre (Py), burnt sienna (Po), and a mixture of Pr + Py + Po color group (P3)], was used in this study. Each of the 5 experimental groups consisted of 5 specimens. All specimens were placed in a 250 ml glass beaker filled with 150 ml of water (replenished for each microwave exposure). An exposure of 6 minutes was used 18 times (simulating 1.5 years of microwave sterilization with one 6 minute exposure monthly). Reflectance values were measured by spectrophotometer. Three- and two-way analyses of variance with repeated measures were performed for the color difference (DeltaE*) with the factors of group/color/months, and group/months, respectively. Means were compared by Tukey Honest Significant Difference (HSD) multiple range test calculated at the 0.05 level of significance using SPSS. RESULTS: The trained human eye can detect color changes (DeltaE*) greater than 1.0. Most DeltaE* values of the red pigment group at all intervals and the mixed pigment group at 15- and 18- month intervals increased significantly greater than 1.0 (p < 0.001) compared with the control group. Yellow and burnt sienna groups remained the most color stable over time with DeltaE* values below 0.35. CONCLUSIONS: Lack of color stability of red dry earth pigmented A-2186 silicone maxillofacial elastomers was clinically significant after 12-month exposure to microwave energy as compared with yellow, burnt sienna, and opacified A-2186 dry earth pigments. 相似文献
88.
Lars von Knorring Béla G. L. Almay Jan Häggendal Folke Johansson Lars Oreland Lennart Wetterberg 《European archives of psychiatry and clinical neuroscience》1986,236(3):131-138
Summary The aim of the present study was to investigate the discriminative power of a series of variables (including determination of depressive symptomatology by means of a visual analogue scale, determination of personality traits by means of the Karolinska Scales of Personality, determination of monoamine metabolites in CSF, platelet MAO activities, serum cortisol before and after dexamethasone suppression and urinary melatonin) in differentiating (a) chronic pain patients from healthy subjects, and (b) patients with idiopathic pain syndromes from patients with neurogenic pain syndromes. Separately each of the measures gave a significant but often low contribution to the discrimination, while a combination of several measures gave a complete discrimination both between healthy subjects and patients with chronic pain syndromes and between patients with idiopathic and neurogenic pain syndromes, respectively.Supported in part by grants from the Swedish Medical Research Council (grants no. 3371, 4145 and 5740) and by a grant from Stiftelsen Söderström-Königska Sjukhemmet 相似文献
89.
90.