全文获取类型
收费全文 | 155987篇 |
免费 | 31602篇 |
国内免费 | 2393篇 |
专业分类
耳鼻咽喉 | 5262篇 |
儿科学 | 5534篇 |
妇产科学 | 2591篇 |
基础医学 | 3826篇 |
口腔科学 | 1580篇 |
临床医学 | 27176篇 |
内科学 | 48095篇 |
皮肤病学 | 7672篇 |
神经病学 | 15093篇 |
特种医学 | 6620篇 |
外国民族医学 | 1篇 |
外科学 | 42034篇 |
综合类 | 279篇 |
现状与发展 | 72篇 |
一般理论 | 8篇 |
预防医学 | 7420篇 |
眼科学 | 3458篇 |
药学 | 1293篇 |
中国医学 | 10篇 |
肿瘤学 | 11958篇 |
出版年
2024年 | 687篇 |
2023年 | 4811篇 |
2022年 | 1212篇 |
2021年 | 3124篇 |
2020年 | 6096篇 |
2019年 | 2217篇 |
2018年 | 7445篇 |
2017年 | 7390篇 |
2016年 | 8499篇 |
2015年 | 8517篇 |
2014年 | 15622篇 |
2013年 | 15773篇 |
2012年 | 5695篇 |
2011年 | 5683篇 |
2010年 | 10491篇 |
2009年 | 14352篇 |
2008年 | 5957篇 |
2007年 | 4209篇 |
2006年 | 6684篇 |
2005年 | 3968篇 |
2004年 | 3190篇 |
2003年 | 2169篇 |
2002年 | 2258篇 |
2001年 | 3984篇 |
2000年 | 3212篇 |
1999年 | 3365篇 |
1998年 | 3723篇 |
1997年 | 3514篇 |
1996年 | 3401篇 |
1995年 | 3255篇 |
1994年 | 1989篇 |
1993年 | 1598篇 |
1992年 | 1475篇 |
1991年 | 1502篇 |
1990年 | 1190篇 |
1989年 | 1268篇 |
1988年 | 1080篇 |
1987年 | 927篇 |
1986年 | 962篇 |
1985年 | 798篇 |
1984年 | 623篇 |
1983年 | 587篇 |
1982年 | 557篇 |
1981年 | 437篇 |
1980年 | 409篇 |
1979年 | 386篇 |
1978年 | 371篇 |
1977年 | 447篇 |
1975年 | 346篇 |
1972年 | 353篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
152.
Ferrari Angela MD Lozzi Gian Piero MD Fargnoli Maria Concetta MD Peris Ketty MD 《Dermatologic surgery》2005,31(11):1448-1450
Background. A combined nevus most commonly consists of a blue nevus in combination with a Clark or Spitz nevus. Dermoscopically, combined nevus can mimic melanoma owing to the presence of dermoscopic features common to both types of lesions. Benign clinical and dermoscopic changes can occur in nevi over time, especially in children and young adults.
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
153.
154.
Kun Hwang MD PhD Ei Tae Kim MD Se Il Lee MD DMSc 《The Journal of foot and ankle surgery》2005,44(6):473-477
The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence. 相似文献
155.
156.
Ullmann Yehuda MD Shoshani Oren MD Fodor Adriana MD Ramon Yitzhak MD Carmi Nurit PhD Eldor Liron MD Gilhar Amos MD 《Dermatologic surgery》2005,31(10):1304-1307
BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient. 相似文献
157.
158.
159.
160.
Weiss Robert A. MD McDaniel David H. MD † Geronemus Roy G. MD ‡ MARGARET A. WEISS MD KAREN L. BEASLEY MD § Munavalli Girish M. MD§ § Bellew Supriya G. MD ¶ 《Dermatologic surgery》2005,31(S3):1199-1205
Background. Light-emitting diode (LED) photomodulation is a novel nonthermal technology used to modulate cellular activity with light.
Objective:. We describe our experience over the last 2 years using 590 nm LED photomodulation within a dermatologic surgery environment.
Methods. Practical use of nonthermal light energy and emerging applications in 3,500 treatments delivered to 900 patients is detailed.
Results. LED photomodulation has been used alone for skin rejuvenation in over 300 patients but has been effective in augmentation of results in 600 patients receiving concomitant nonablative thermal and vascular treatments such as intense pulsed light, pulsed dye laser, KTP and infrared lasers, radiofrequency energy, and ablative lasers.
Conclusion:. LED photomodulation reverses signs of photoaging using a new nonthermal mechanism. The anti-inflammatory component of LED in combination with the cell regulatory component helps improve the outcome of other thermal-based rejuvenation treatments. 相似文献
Objective:. We describe our experience over the last 2 years using 590 nm LED photomodulation within a dermatologic surgery environment.
Methods. Practical use of nonthermal light energy and emerging applications in 3,500 treatments delivered to 900 patients is detailed.
Results. LED photomodulation has been used alone for skin rejuvenation in over 300 patients but has been effective in augmentation of results in 600 patients receiving concomitant nonablative thermal and vascular treatments such as intense pulsed light, pulsed dye laser, KTP and infrared lasers, radiofrequency energy, and ablative lasers.
Conclusion:. LED photomodulation reverses signs of photoaging using a new nonthermal mechanism. The anti-inflammatory component of LED in combination with the cell regulatory component helps improve the outcome of other thermal-based rejuvenation treatments. 相似文献