全文获取类型
收费全文 | 6875篇 |
免费 | 385篇 |
国内免费 | 377篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 12篇 |
妇产科学 | 24篇 |
基础医学 | 831篇 |
口腔科学 | 1299篇 |
临床医学 | 569篇 |
内科学 | 1391篇 |
皮肤病学 | 69篇 |
神经病学 | 86篇 |
特种医学 | 146篇 |
外科学 | 334篇 |
综合类 | 759篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 555篇 |
眼科学 | 57篇 |
药学 | 820篇 |
3篇 | |
中国医学 | 579篇 |
肿瘤学 | 69篇 |
出版年
2024年 | 29篇 |
2023年 | 165篇 |
2022年 | 619篇 |
2021年 | 703篇 |
2020年 | 232篇 |
2019年 | 183篇 |
2018年 | 186篇 |
2017年 | 158篇 |
2016年 | 190篇 |
2015年 | 250篇 |
2014年 | 520篇 |
2013年 | 735篇 |
2012年 | 339篇 |
2011年 | 359篇 |
2010年 | 285篇 |
2009年 | 243篇 |
2008年 | 275篇 |
2007年 | 245篇 |
2006年 | 235篇 |
2005年 | 217篇 |
2004年 | 179篇 |
2003年 | 189篇 |
2002年 | 136篇 |
2001年 | 116篇 |
2000年 | 82篇 |
1999年 | 76篇 |
1998年 | 67篇 |
1997年 | 59篇 |
1996年 | 38篇 |
1995年 | 36篇 |
1994年 | 45篇 |
1993年 | 34篇 |
1992年 | 60篇 |
1991年 | 36篇 |
1990年 | 31篇 |
1989年 | 26篇 |
1988年 | 20篇 |
1987年 | 30篇 |
1986年 | 28篇 |
1985年 | 39篇 |
1984年 | 24篇 |
1983年 | 22篇 |
1982年 | 24篇 |
1981年 | 8篇 |
1980年 | 14篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1977年 | 12篇 |
1976年 | 10篇 |
1975年 | 8篇 |
排序方式: 共有7637条查询结果,搜索用时 0 毫秒
1.
Total global biodiversity is estimated at between 3 and 500 × 106 species of prokaryote and eukaryote organisms spread across 70 or more phyla. The marine macrofauna alone are estimated between 0.5 and 30 × 106 species and represents a broader range of taxonomic diversity than that found in the terrestrial environment, which has been the traditional source of natural products. With a typical eukaryote possessing 50,000 genes, the global marine macrofauna are the source of 2.5 × 1010 to 1.5 × 1012 primary products and an associated extensive range of secondary products. However, only a few thousand novel compounds from marine organisms have been described. These compounds have proven unique in chemical and pharmacological terms but, as yet, no therapeutic agents have resulted. Given a broader drug discovery strategy, and facilitated by technological advances, it is predicted that the characterisation of marine chemical diversity will be accelerated. Strategies for drug discovery from the virtually untapped chemical diversity of marine organisms are discussed. © 1994 Wiley-Less, Inc. 相似文献
2.
一些损伤和疾病平时罕见,特殊情况下可以发生,造成严重危害。特殊情况主要包括严重事故、灾害、战争、恐怖主义活动以及特殊环境与特殊作业的危害等。本阐述了现代战争中发生的贫铀武器伤害、燃料空气炸弹伤害、微波武器伤害和战时精神疾病;可能源于恐怖主义活动的炭疽、天花;严重事故性伤害中的核事故、化学事故和煤矿事故伤害;严重灾害中的地震、海难(海战)落海伤害。中介绍了这些伤病的发生情况、伤害特点与医学救治。 相似文献
3.
4.
5.
医用低值材料采供管理的探讨 总被引:4,自引:2,他引:2
医疗消耗材料是医疗工作开展的基础,本文从医用低值消耗材料的计划制定、材料采购、库房库存结构、材料供应、成本核算等多方面探讨了如何对医疗消耗材料进行科学管理,这对医院的医疗发展和管理建设有着重要意义。 相似文献
6.
Industrial back belts and low back pain: Mechanisms and outcomes 总被引:1,自引:0,他引:1
The recent increased utilization of industrial back belts as personal protective equipment in the workplace has generated considerable controversy among occupational health and safety professionals in the United States. The purpose of this article is to review the literature regarding proposed mechanisms of action of these devices and studies related to outcome of belt utilization in the prevention of low back pain and disability in the workplace. At the present time, neither the suspected mechanisms of action nor the efficacy of these devices in the primary, secondary, and tertiary prevention of work-related low back pain has been adequately demonstrated in clinical trials. As a result, generally accepted guidelines regarding the safe use of belts in the occupational setting have not been established. Based on this review it is recommended that further well-controlled, prospective, randomized clinical trials are necessary to evaluate the effectiveness of these devices as personal protective equipment. During the interim, the decision to prescribe belts to employees in the workplace should be at the discretion of an adequately trained occupational health care provider. These devices should not be provided as an alternative to appropriate administrative and/or engineering controls. 相似文献
7.
本文主要研究了无机玻璃纤维增强聚甲基丙烯酸甲酯(PMMA)/羟基磷灰石(HA)复合材料的制备及相关的性能测试,证明此复合材料性能稳定、物理机械强度高以及工艺简单,有良好的应用前景。 相似文献
8.
9.
In this paper an uncomplicated method for the simultaneous detection and semiquantitation of 11 of the 12 commonly studied antinuclear antibodies (ANA) in a single run is described. This new application of checkerboard immunoblotting (CBIB) is based upon available technology and employs purified antigens which can be either purchased or produced in-house. CBIB requires no electronic instrument, can be formatted to meet the needs of the user, is rapidly performed, and has acceptable labor and materials costs. Data on the use of the method to examine available reference antisera is presented. CBIB has also proven practical for the clinical study of 18 sera, at two dilutions per membrane, for each set of specific antinuclear antibodies, also at two or more dilutions. 相似文献
10.
颌面赝复材料研究进展 总被引:5,自引:0,他引:5
赵信义 《国际生物医学工程杂志》2006,29(3):178-183
综述了目前口腔颌面赝复材料种类、性能要求及各种颌面赝复材料的组成、性能和应用过程,探讨了各种颌面赝复材料的优势及不足,指出目前临床应用的颌面赝复材料以硅橡胶类为主,其中又以中温硫化硅橡胶和室温硫化硅橡胶综合性能较好,应用最为广泛。 相似文献