全文获取类型
收费全文 | 1335113篇 |
免费 | 100194篇 |
国内免费 | 4271篇 |
专业分类
耳鼻咽喉 | 16797篇 |
儿科学 | 43581篇 |
妇产科学 | 36357篇 |
基础医学 | 197819篇 |
口腔科学 | 35902篇 |
临床医学 | 129549篇 |
内科学 | 258054篇 |
皮肤病学 | 26371篇 |
神经病学 | 111851篇 |
特种医学 | 48169篇 |
外国民族医学 | 366篇 |
外科学 | 184021篇 |
综合类 | 28773篇 |
现状与发展 | 1篇 |
一般理论 | 460篇 |
预防医学 | 114360篇 |
眼科学 | 28979篇 |
药学 | 98823篇 |
6篇 | |
中国医学 | 3167篇 |
肿瘤学 | 76172篇 |
出版年
2021年 | 10903篇 |
2019年 | 11631篇 |
2018年 | 16313篇 |
2017年 | 12285篇 |
2016年 | 13243篇 |
2015年 | 15190篇 |
2014年 | 20795篇 |
2013年 | 32046篇 |
2012年 | 44230篇 |
2011年 | 46878篇 |
2010年 | 27071篇 |
2009年 | 24918篇 |
2008年 | 42707篇 |
2007年 | 45047篇 |
2006年 | 45160篇 |
2005年 | 43583篇 |
2004年 | 41553篇 |
2003年 | 39489篇 |
2002年 | 38300篇 |
2001年 | 60841篇 |
2000年 | 62512篇 |
1999年 | 52275篇 |
1998年 | 14578篇 |
1997年 | 13275篇 |
1996年 | 13115篇 |
1995年 | 12457篇 |
1994年 | 11628篇 |
1993年 | 10921篇 |
1992年 | 41567篇 |
1991年 | 40759篇 |
1990年 | 39445篇 |
1989年 | 37342篇 |
1988年 | 34582篇 |
1987年 | 33696篇 |
1986年 | 32151篇 |
1985年 | 30638篇 |
1984年 | 23035篇 |
1983年 | 19590篇 |
1982年 | 11752篇 |
1979年 | 20804篇 |
1978年 | 14814篇 |
1977年 | 12064篇 |
1976年 | 11876篇 |
1975年 | 12110篇 |
1974年 | 14800篇 |
1973年 | 14472篇 |
1972年 | 13356篇 |
1971年 | 12418篇 |
1970年 | 11485篇 |
1969年 | 10410篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
L L Polla S L Jacques R J Margolis M R Prince R R Anderson J A Parrish O T Tan 《Annales de dermatologie et de vénéréologie》1987,114(4):497-505
Since 1962, lasers have been used in dermatology and have become the first choice in the treatment of superficial, vascular ectasia. Lasers are unique sources of light; they are coherent, monochromatic, collimated and intense. By careful selection of wavelength, pulse duration, and intensity, it is often possible to selectively confine a laser effect to a specific histologic structure in tissue, depending upon the tissue properties. The ideal treatment of Port Wine Stains (PWS) should irreversibly damage the ectatic vessels but minimize heating of the epidermis and superficial dermis. A theory, called selective photothermolysis, predicts the optimal combination of laser parameters of achieving this ideal treatment of PWS to be a wavelength of 577 nm, a pulse duration of 0.35-10 msec, and an energy per surface area of about 7-8 J/cm2. Laser wavelength: The wavelength of 577 nm is preferred because it: maximizes the selective absorption by hemoglobin, minimizes absorption by epidermal melanin, provides sufficient depth of penetration in the blood to coagulate 0.1 mm vessels allows penetration of light into dermis up to 1 mm. Laser pulse duration: A pulse-width in the range of 0.35-10 msec allows the temperature elevation to be uniform inside the vessel and to be confined to the vessel area. Shorter pulses superheat the red blood cells causing explosive boiling and hemorrhage. Longer pulses allow heat to diffuse away from vessels, requiring greater energies per pulse to achieve vessel damage. An increased energy per pulse increases the risk of excessive damage to surrounding tissue.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
To determine the relationship between severity of illness and mortality, therapeutic intervention score (TISS) and acute physiology score (APS) were determined on admission to the Surgical Intensive Care Unit (SICU). Patients were divided into survivors and nonsurvivors and differences were compared by chi-square analysis. The 1524 patients admitted to the SICU during a 12-month period had a mean TISS of 3.03 and a mean APS of 13. The average length of stay (LOS) was 3.75 days. Of the 1524 patients, 97 (6.4%) died. The number of nonsurvivors increased with higher TISS and APS scores (P less than 0.001). There were no deaths in the TISS Category 1 patients or in the APS 0-5 group. Mortality rates dramatically increased with APS greater than 20 (P less than 0.001). There were 1286 patients with APS less than 20, and 24 (2%) of these patients died, whereas 73 (31%) of 238 patients with APS greater than 20 died. Nonsurvivors had a mean TISS of 3.6, mean APS of 27, and LOS of 4.88 days, all of which totals were higher than the survivors' totals. In this study population, risk of death was one in three if the APS was greater than 20. These data indicate that TISS and APS scores are effective means of assessing mortality risk in SICU patients. 相似文献
993.
994.
995.
996.
997.
998.
999.
1000.
The health care supervisor responsible for establishing a therapeutic milieu within a traditional hospital organization will have greater success if these suggested management strategies are employed. Decentralizing, improving organizational communication, and clarifying interdisciplinary role relationships are the strategies that support the integration of differing organizational approaches to management. 相似文献