全文获取类型
收费全文 | 24807篇 |
免费 | 1307篇 |
国内免费 | 150篇 |
专业分类
耳鼻咽喉 | 149篇 |
儿科学 | 610篇 |
妇产科学 | 391篇 |
基础医学 | 3066篇 |
口腔科学 | 659篇 |
临床医学 | 1686篇 |
内科学 | 6435篇 |
皮肤病学 | 464篇 |
神经病学 | 2278篇 |
特种医学 | 806篇 |
外科学 | 3873篇 |
综合类 | 171篇 |
一般理论 | 1篇 |
预防医学 | 642篇 |
眼科学 | 461篇 |
药学 | 1747篇 |
中国医学 | 28篇 |
肿瘤学 | 2797篇 |
出版年
2023年 | 142篇 |
2022年 | 283篇 |
2021年 | 462篇 |
2020年 | 254篇 |
2019年 | 330篇 |
2018年 | 481篇 |
2017年 | 343篇 |
2016年 | 418篇 |
2015年 | 489篇 |
2014年 | 571篇 |
2013年 | 718篇 |
2012年 | 1099篇 |
2011年 | 1212篇 |
2010年 | 684篇 |
2009年 | 579篇 |
2008年 | 1022篇 |
2007年 | 1185篇 |
2006年 | 1166篇 |
2005年 | 1175篇 |
2004年 | 1099篇 |
2003年 | 1030篇 |
2002年 | 1055篇 |
2001年 | 950篇 |
2000年 | 920篇 |
1999年 | 868篇 |
1998年 | 313篇 |
1997年 | 243篇 |
1996年 | 286篇 |
1995年 | 180篇 |
1994年 | 180篇 |
1993年 | 159篇 |
1992年 | 542篇 |
1991年 | 494篇 |
1990年 | 513篇 |
1989年 | 461篇 |
1988年 | 438篇 |
1987年 | 435篇 |
1986年 | 380篇 |
1985年 | 397篇 |
1984年 | 289篇 |
1983年 | 196篇 |
1979年 | 214篇 |
1978年 | 145篇 |
1977年 | 139篇 |
1974年 | 129篇 |
1971年 | 136篇 |
1970年 | 132篇 |
1969年 | 128篇 |
1968年 | 139篇 |
1967年 | 141篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Hideyuki Masuda Makoto Kimura Akiko Nishioka Hiroshi Kato Akimichi Morita 《Journal of dermatological science》2019,93(2):109-115
Background
Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.Objective
We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.Methods
HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.Results
The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.Conclusion
We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas. 相似文献2.
3.
4.
5.
6.
Yasuyuki Suzuki Kazuyuki Daitoku Masahito Minakawa Kozo Fukui Ikuo Fukuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(1):44-46
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary
atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation
which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result
in progressive aortic regurgitation for a short period. 相似文献
7.
Factors associated with levels of physical activity at work and during leisure time were analyzed among 577 subjects who had been selected as population controls for a case-control study by random selection from telephone directories. The intensity of physical activity at work was inversely associated with body mass index, the proportion of professionals & managers, consumption of western style breakfast, coffee, butter/margarine, and whisky; and positively associated with rice intake. Frequency of physical activities during leisure time was positively associated with consumption of vegetables, fruits, mushrooms, milk, cheese and coffee, and moderation in eating; and inversely associated with rice intake and the prevalence of gastrointestinal symptoms and medication. The association of physical activity with these factors should be considered in studying its relationship to disease risk. 相似文献
8.
Tadashi Kato 《Seishin shinkeigaku zasshi》2002,104(6):509-512
9.
10.