全文获取类型
收费全文 | 3623篇 |
免费 | 481篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 107篇 |
妇产科学 | 300篇 |
基础医学 | 320篇 |
口腔科学 | 160篇 |
临床医学 | 1041篇 |
内科学 | 589篇 |
皮肤病学 | 84篇 |
神经病学 | 214篇 |
特种医学 | 280篇 |
外科学 | 270篇 |
综合类 | 97篇 |
预防医学 | 231篇 |
眼科学 | 43篇 |
药学 | 237篇 |
中国医学 | 5篇 |
肿瘤学 | 124篇 |
出版年
2023年 | 50篇 |
2021年 | 32篇 |
2020年 | 57篇 |
2019年 | 47篇 |
2018年 | 87篇 |
2017年 | 111篇 |
2016年 | 97篇 |
2015年 | 130篇 |
2014年 | 141篇 |
2013年 | 161篇 |
2012年 | 125篇 |
2011年 | 134篇 |
2010年 | 157篇 |
2009年 | 143篇 |
2008年 | 111篇 |
2007年 | 143篇 |
2006年 | 125篇 |
2005年 | 112篇 |
2004年 | 94篇 |
2003年 | 117篇 |
2002年 | 92篇 |
2001年 | 106篇 |
2000年 | 73篇 |
1999年 | 108篇 |
1998年 | 116篇 |
1997年 | 129篇 |
1996年 | 117篇 |
1995年 | 113篇 |
1994年 | 84篇 |
1993年 | 69篇 |
1992年 | 59篇 |
1991年 | 79篇 |
1990年 | 44篇 |
1989年 | 87篇 |
1988年 | 66篇 |
1987年 | 51篇 |
1986年 | 63篇 |
1985年 | 63篇 |
1984年 | 47篇 |
1983年 | 43篇 |
1982年 | 27篇 |
1981年 | 31篇 |
1980年 | 34篇 |
1979年 | 31篇 |
1978年 | 36篇 |
1977年 | 30篇 |
1976年 | 22篇 |
1975年 | 22篇 |
1973年 | 20篇 |
1970年 | 12篇 |
排序方式: 共有4117条查询结果,搜索用时 15 毫秒
1.
2.
D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
3.
4.
S M Sheridan 《Journal of the Irish Dental Association》1987,33(2-4):37-40
5.
L E Sheridan 《Clinics in Podiatric Medicine and Surgery》1987,4(1):63-74
A 4.5-year follow-up retrospective study on the use of epiphysiodesis procedure for juvenile hallux valgus deformity and metatarsus primus adductus deformity shows a good reduction of deformity in nine patients with minimal change in one patient that can be explained due to the timing of the procedure. This is a minor operation for juvenile bunion deformities, using epiphyseal arrest techniques. The only complication to this procedure was one case with a noted metatarsus primus elevatus due to incomplete epiphyseal arrest from dorsal to plantar. This procedure has been found to be a safe and effective way of dealing with juvenile hallux valgus deformity when metatarsus primus adductus is the deforming force. It should be stated that in all cases a follow-up biomechanical examination and casting for orthotics took place and to date no complications, other than what has been previously mentioned, has occurred. I shall continue to perform this procedure where indicated and shall report my findings as they become available. 相似文献
6.
BACKGROUND: Previously, complement activation has been associated with decompression sickness (DCS). However data, both in humans and in animals, are controversial. Hypothesis: Complement activation and depletion occurs after exposure to the hyperbaric environment and is associated with increasing risk of DCS. METHODS: We obtained serological samples from 102 dives (120-300 feet of seawater) with a constant partial pressure of O2 set at 1.3 ATA in thirty-five U.S. Navy diver volunteers. Blood was obtained within one hour of diving and within one hour of surfacing. Plasma was extracted and analyzed for complement depletion. The risk of DCS was estimated using a validated model of DCS risk. RESULTS: Pre-post dive concentrations of C3a were significantly related to estimated risk of DCS (Figure 1), but the variation in predicted DCS explained by C3a was small (correlation co-efficient (r2 = 0.19, p < 0.0001). CONCLUSIONS: There was a reduction in total Ca3 levels in divers after exposure to dives with a high estimated risk of DCS. This decomplementation appeared to increase as the estimated risk of DCS increased. 相似文献
7.
V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
8.
9.
10.