全文获取类型
收费全文 | 1772篇 |
免费 | 135篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 64篇 |
妇产科学 | 23篇 |
基础医学 | 190篇 |
口腔科学 | 59篇 |
临床医学 | 214篇 |
内科学 | 281篇 |
皮肤病学 | 19篇 |
神经病学 | 151篇 |
特种医学 | 111篇 |
外科学 | 235篇 |
综合类 | 28篇 |
一般理论 | 3篇 |
预防医学 | 130篇 |
眼科学 | 10篇 |
药学 | 202篇 |
中国医学 | 6篇 |
肿瘤学 | 158篇 |
出版年
2021年 | 29篇 |
2019年 | 26篇 |
2018年 | 19篇 |
2017年 | 14篇 |
2016年 | 13篇 |
2015年 | 24篇 |
2014年 | 30篇 |
2013年 | 47篇 |
2012年 | 70篇 |
2011年 | 69篇 |
2010年 | 19篇 |
2009年 | 34篇 |
2008年 | 41篇 |
2007年 | 54篇 |
2006年 | 55篇 |
2005年 | 45篇 |
2004年 | 63篇 |
2003年 | 67篇 |
2002年 | 60篇 |
2001年 | 74篇 |
2000年 | 74篇 |
1999年 | 53篇 |
1998年 | 23篇 |
1997年 | 14篇 |
1996年 | 14篇 |
1995年 | 16篇 |
1994年 | 18篇 |
1993年 | 31篇 |
1992年 | 63篇 |
1991年 | 62篇 |
1990年 | 69篇 |
1989年 | 40篇 |
1988年 | 36篇 |
1987年 | 59篇 |
1986年 | 58篇 |
1985年 | 43篇 |
1984年 | 42篇 |
1983年 | 26篇 |
1982年 | 23篇 |
1981年 | 22篇 |
1980年 | 26篇 |
1979年 | 38篇 |
1978年 | 27篇 |
1977年 | 15篇 |
1976年 | 16篇 |
1975年 | 13篇 |
1974年 | 14篇 |
1972年 | 15篇 |
1970年 | 19篇 |
1969年 | 14篇 |
排序方式: 共有1908条查询结果,搜索用时 12 毫秒
1.
Aim : The study was designed to determine the effect of computerized nutrition information on consumer food choice in two workplace restaurants, one in which customers had to pay for their lunch and the other providing a free lunch. Methods : Customers entering the restaurants were asked to make selections from the menu on a computer screen. The energy, saturated fatty acids, non-milk extrinsic sugars and non-starch polysaccharide content of the meal selected was displayed graphically in proportion to the dietary reference values. They were given the opportunity to change their selected meal and the composition of all meals was recorded. Results : The nutritional composition of the first meal provoked 16% of customers to make a second selection. The proportion of energy in the first selection had been 31% higher for saturated fatty acids and 23% higher for non-milk extrinsic sugars than the first selection made by people who were satisfied with their first choice. In their second attempt they succeeded in reducing both nutrients to levels similar to those present in the meals selected by people who had been satisfied with their first selection. Customers>> selections for non-starch polysaccharide and energy did not differ between the groups. The main changes made by customers to achieve improved second choices were to omit dishes (44%), add dishes (19%), make changes within a menu category (46%), and make changes from one menu category to another (26%). Conclusion : It was concluded that provision of graphical nutrition information on a computer screen could be used by a subset of the users of both restaurants to enable them to improve their menu selections to a similar composition to that selected by the other people who used the computer system. 相似文献
2.
Dermal absorption of the insecticide lindane was determined following topical application of ring 14C-labeled lindane to the tail of Sprague-Dawley rats. The tail was tested as a practical alternative to the rat mid-dorsal (back) region, and the data obtained were compared to those with rat back and with those of rhesus monkeys in our previous reports. There was no significant difference between total percentage urinary 14C recovery for rats dosed on the tail with occlusive tail covers (52 +/- 6.2%; t1/2 = 2.7 d) compared to those with nonocclusive covers (55 +/- 4.4%; t1/2 = 2.9 d). Neither the total percentage urinary recovery nor the t1/2 values obtained for the rat tail and rat back models differed significantly. Carbon-14 activity was still detectable in urine samples taken after 72 d post-treatment. However, an extensive tissue analysis failed to demonstrate 14C activity persisting at 72 d, with the exception of trace levels detected in blood serum and tail tissue. Advantages of the rat tail model are highlighted. 相似文献
3.
4.
A total of 277 third and fourth year medical students and 304 house officers and senior house officers were asked to prioritise the content and methods of clinical teaching. Response rates were poor, but similar to that in market surveys. Bedside teaching and medical clerking were considered the most valuable methods of teaching and training in practical procedures such as venepunctures and urinary catheterisation was seen as valuable. The design of new curricula in medical education will need to accommodate the views of its clients. 相似文献
5.
6.
7.
8.
9.
10.