全文获取类型
收费全文 | 2233篇 |
免费 | 173篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 100篇 |
儿科学 | 61篇 |
妇产科学 | 30篇 |
基础医学 | 195篇 |
口腔科学 | 29篇 |
临床医学 | 223篇 |
内科学 | 507篇 |
皮肤病学 | 228篇 |
神经病学 | 134篇 |
特种医学 | 143篇 |
外科学 | 238篇 |
综合类 | 41篇 |
预防医学 | 207篇 |
眼科学 | 52篇 |
药学 | 99篇 |
肿瘤学 | 143篇 |
出版年
2021年 | 20篇 |
2020年 | 10篇 |
2019年 | 15篇 |
2018年 | 35篇 |
2017年 | 26篇 |
2016年 | 48篇 |
2015年 | 49篇 |
2014年 | 66篇 |
2013年 | 97篇 |
2012年 | 79篇 |
2011年 | 68篇 |
2010年 | 54篇 |
2009年 | 77篇 |
2008年 | 66篇 |
2007年 | 71篇 |
2006年 | 65篇 |
2005年 | 57篇 |
2004年 | 76篇 |
2003年 | 46篇 |
2002年 | 32篇 |
2001年 | 43篇 |
2000年 | 49篇 |
1999年 | 65篇 |
1998年 | 83篇 |
1997年 | 67篇 |
1996年 | 72篇 |
1995年 | 61篇 |
1994年 | 67篇 |
1993年 | 50篇 |
1992年 | 76篇 |
1991年 | 45篇 |
1990年 | 69篇 |
1989年 | 70篇 |
1988年 | 75篇 |
1987年 | 47篇 |
1986年 | 39篇 |
1985年 | 23篇 |
1984年 | 46篇 |
1983年 | 27篇 |
1982年 | 24篇 |
1981年 | 28篇 |
1980年 | 23篇 |
1979年 | 9篇 |
1978年 | 14篇 |
1976年 | 16篇 |
1975年 | 10篇 |
1973年 | 10篇 |
1971年 | 9篇 |
1966年 | 9篇 |
1964年 | 14篇 |
排序方式: 共有2430条查询结果,搜索用时 15 毫秒
1.
D Monnier† C Vidal‡ L Martin§ A Danzon¶ F Pelletier† E Puzenat† MP Algros†† D Blanc† R Laurent† PH Humbert† F Aubin† 《Journal of the European Academy of Dermatology and Venereology》2006,20(10):1237-1242
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating. 相似文献
2.
3.
4.
In rodents, chronic estrogenization has been shown to induce degeneration of dendrites and myelin figures in the hypothalamic arcuate nucleus adjacent to peroxidase-positive astrocyte processes. Because in this brain region estradiol is metabolized to 2-hydroxyestradiol (catecholestrogen), we hypothesized that the latter may be oxidized by the astrocytic peroxidase activity to cytotoxic ortho-semiquinones as occurs in peripheral tissues. Cysteamine induces nonenzymatic peroxidase activity in cultured astroglia identical to that observed in vivo. Using electron spin resonance, we demonstrate robust peroxidase-catalyzed oxidation of 2-hydroxyestradiol and dopamine by cysteamine-pretreated astrocyte cultures relative to untreated controls. These results implicate the peroxidase-positive astrocytes in the pathogenesis of estradiol-related hypothalamic damage, parkinsonism, and other free-radical-related neurologic disorders. 相似文献
5.
L. TIMMER-DE MIK M.D. D.M. BROEKHUIJSEN-VAN HENTEN M.D. † J.M. OLDHOFF M.D. PH.D. D.B. DE GEER M.D. ‡ V. SIGURDSSON M.D. PH.D. S.G.M.A. PASMANS M.D. PH.D. 《Pediatric dermatology》2009,26(3):358-360
Abstract: In Sweet's syndrome, the essential features are the characteristic morphology of the lesions, their histologic appearance, the dramatic response to corticosteroids and the absence of scarring. We report an 8-month-old infant in whom Sweet's syndrome was diagnosed and who developed acquired cutis laxa in the skin lesions. 相似文献
6.
Fiona C.L. Bull Ph.D. M.Sc. Elise C.C. Schipper M.A. Konrad Jamrozik M.B.B.S. D.Phil. FAFPHM Brian A. Blanksby Ph.D. M.Sc. Dip.Ed. 《Preventive medicine》1997,26(6):866-873
Background.Physical inactivity is recognized as an important public health issue. Yet little is known about doctors' knowledge, attitude, skills, and resources specifically relating to the promotion of physical activity. Our survey assessed the current practice, perceived desirable practice, confidence, and barriers related to the promotion of physical activity in family practice.Methods.A questionnaire was developed and distributed to all 1,228 family practitioners in Perth, Western Australia.Results.We received a 71% response (n= 789). Family practitioners are most likely to recommend walking to sedentary adults to improve fitness and they are aware of the major barriers to patients participating in physical activity. Doctors are less confident at providing specific advice on exercise and may require further skills, knowledge, and experience. Although they promote exercise to patients through verbal advice in the consultation, few use written materials or referral systems.Conclusions.There are significant differences between self-reports of current practice and perceived desirable practice in the promotion of physical activity by doctors. Future strategies need to address the self-efficacy of family physicians and involve resources of proven effectiveness. The potential of referral systems for supporting efforts to increase physical activity by Australians should be explored. 相似文献
7.
HUGH F. MOLLOY F.A.C.D. ERIC LAMONT-GREGORY M.SC. CHRIS IDZIKOWSKI PH.D. F.B.PS.S. TERENCE J. RYAN D.M. F.R.C.P. 《International journal of dermatology》1993,32(9):668-672
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive. 相似文献
8.
Ch. Offergeld J. Kromeier A. Aschendorff W. Maier Th. Klenzner Th. Beleites Th. Zahnert J. Schipper R. Laszig 《European archives of oto-rhino-laryngology》2007,264(4):345-351
Imaging is an essential diagnostic tool in reconstructive middle ear surgery, especially in pre-operative planning. Due to ongoing improvement of imaging quality and development of new imaging techniques like e.g. rotational tomography (RT) post-operative follow-up and immediate evaluation of surgical results may become more important. The aim of this experimental study was to evaluate RT as a new tool for postoperative determination of middle ear anatomy and implant position in temporal bones. RT was performed in ten temporal bone specimen after insertion of different middle ear prostheses concerning material, shape and length (PORP; TORP; Stapes piston). An implantable hearing device (Symphonix Soundbridge®) was also implanted and visualized. For comparison some specimen additionally underwent conventional computed tomography (CT), including the newest technology. Characterization of anatomical structures of the temporal bone using RT was of comparable quality to conventional CT-scans in all investigated specimen while requiring approximately 30% of the CT’s irradiation exposure. Unlike CT the RT showed almost no problems due to metallic artefacts of the implanted prostheses. Furthermore RT enabled a 3-dimensional view of the temporal bone and angle determination of inserted prostheses towards the tympanic membrane and/or the malleus handle. Detailed imaging of the prostheses allowed determination of shape, material and localization within the specimen’s reconstructed middle ear. The new imaging technique of RT allows precise presentation of anatomical structures and middle ear implants in temporal bones. Following these experimental results it will be our future work to evaluate this method in clinical practise. 相似文献
9.
10.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797