全文获取类型
收费全文 | 1206篇 |
免费 | 107篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 50篇 |
妇产科学 | 4篇 |
基础医学 | 155篇 |
口腔科学 | 30篇 |
临床医学 | 114篇 |
内科学 | 225篇 |
皮肤病学 | 26篇 |
神经病学 | 29篇 |
特种医学 | 264篇 |
外科学 | 196篇 |
综合类 | 65篇 |
预防医学 | 54篇 |
眼科学 | 9篇 |
药学 | 122篇 |
肿瘤学 | 31篇 |
出版年
2022年 | 3篇 |
2021年 | 14篇 |
2020年 | 3篇 |
2018年 | 9篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 13篇 |
2014年 | 23篇 |
2013年 | 24篇 |
2012年 | 12篇 |
2011年 | 20篇 |
2010年 | 29篇 |
2009年 | 41篇 |
2008年 | 33篇 |
2007年 | 65篇 |
2006年 | 34篇 |
2005年 | 56篇 |
2004年 | 25篇 |
2003年 | 28篇 |
2002年 | 21篇 |
2001年 | 35篇 |
2000年 | 20篇 |
1999年 | 37篇 |
1998年 | 58篇 |
1997年 | 67篇 |
1996年 | 59篇 |
1995年 | 60篇 |
1994年 | 35篇 |
1993年 | 45篇 |
1992年 | 23篇 |
1991年 | 33篇 |
1990年 | 28篇 |
1989年 | 49篇 |
1988年 | 46篇 |
1987年 | 37篇 |
1986年 | 37篇 |
1985年 | 49篇 |
1984年 | 17篇 |
1983年 | 15篇 |
1982年 | 19篇 |
1981年 | 22篇 |
1980年 | 22篇 |
1979年 | 16篇 |
1978年 | 11篇 |
1977年 | 24篇 |
1976年 | 15篇 |
1975年 | 11篇 |
1974年 | 3篇 |
1972年 | 3篇 |
1966年 | 2篇 |
排序方式: 共有1376条查询结果,搜索用时 0 毫秒
71.
Hypocaloric near isosmotic infusions of crystalline amino acids have the same effect on nitrogen balance as do equal caloric infusions of glucose in burned patients with and without bacteremia. The effects of the two substrates on balance appeared equal and additive. Infusion of a 10 per cent soybean oil emulsion was indistinguishable from low dosage glucose when administered with amino acids. Near isosmotic hypocaloric diets containing glucose and amino acids significantly diminish nitrogen loss in severely burned patients. A combination of both substrates in the infusate is to be preferred. 相似文献
72.
Spontaneous rupture of the kidney with perirenal hematoma. 总被引:4,自引:0,他引:4
73.
74.
75.
76.
77.
78.
Tarsal navicular stress fractures: radiographic evaluation 总被引:3,自引:0,他引:3
Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated. 相似文献
79.
In vitro models are being used to evaluate the toxic and irritating effects of JP-8, a kerosene-based jet fuel. JP-8 components are volatile, which makes in vitro studies difficult to evaluate dose-response relationships due to changes in chemical dosimetry caused by evaporation from the exposure medium. An in vitro approach testing volatile chemical toxicity that we have recently developed was used to evaluate the toxicity of the JP-8 components m-xylene, 1-methylnaphthalene (1-MN), and n-nonane in keratinocytes. Partition coefficients were measured and used to estimate the chemical concentration in the keratinocytes. The EC50 for m-xylene and 1-MN decreased significantly (P < or = 0.05) at 1, 2, and 4h. For n-nonane, no significant decreases in the EC50 values were observed over time; marginal cytotoxicity of n-nonane in keratinocytes was observed at 1h. Within 4h, about 75-90% of each volatile chemical was observed to be lost from the exposure medium when tissues were exposed in unsealed 24-well plates. This decrease resulted in significantly higher medium chemical concentrations needed to obtain EC50 values when compared to tissues exposed in sealed vials. This study demonstrates that chemical evaporation during in vitro exposures can significantly affect toxicological endpoint measurements. Ultimately, relating target cell chemical concentration to cellular responses in vitro could be used in determining an equivalent external dose using a biologically-based mathematical model. 相似文献
80.