全文获取类型
收费全文 | 2575篇 |
免费 | 186篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 103篇 |
妇产科学 | 172篇 |
基础医学 | 320篇 |
口腔科学 | 77篇 |
临床医学 | 225篇 |
内科学 | 534篇 |
皮肤病学 | 62篇 |
神经病学 | 319篇 |
特种医学 | 136篇 |
外科学 | 204篇 |
综合类 | 51篇 |
一般理论 | 2篇 |
预防医学 | 209篇 |
眼科学 | 29篇 |
药学 | 123篇 |
中国医学 | 5篇 |
肿瘤学 | 223篇 |
出版年
2021年 | 29篇 |
2019年 | 42篇 |
2018年 | 49篇 |
2017年 | 37篇 |
2016年 | 45篇 |
2015年 | 33篇 |
2014年 | 56篇 |
2013年 | 63篇 |
2012年 | 113篇 |
2011年 | 114篇 |
2010年 | 59篇 |
2009年 | 55篇 |
2008年 | 110篇 |
2007年 | 129篇 |
2006年 | 102篇 |
2005年 | 111篇 |
2004年 | 81篇 |
2003年 | 102篇 |
2002年 | 70篇 |
2001年 | 80篇 |
2000年 | 100篇 |
1999年 | 67篇 |
1998年 | 51篇 |
1997年 | 29篇 |
1996年 | 28篇 |
1995年 | 25篇 |
1994年 | 31篇 |
1993年 | 19篇 |
1992年 | 46篇 |
1991年 | 59篇 |
1990年 | 58篇 |
1989年 | 73篇 |
1988年 | 77篇 |
1987年 | 50篇 |
1986年 | 52篇 |
1985年 | 49篇 |
1984年 | 36篇 |
1983年 | 29篇 |
1982年 | 29篇 |
1981年 | 22篇 |
1980年 | 23篇 |
1979年 | 25篇 |
1978年 | 23篇 |
1977年 | 23篇 |
1976年 | 31篇 |
1975年 | 28篇 |
1974年 | 26篇 |
1973年 | 24篇 |
1971年 | 19篇 |
1970年 | 19篇 |
排序方式: 共有2807条查询结果,搜索用时 15 毫秒
1.
Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [125I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [123I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [123I]HEAT administered. The total-body dose was found to be 58 mrad per mCi. 相似文献
2.
3.
4.
D G Brown J M Greer E M Webster R A Yonker N L Edwards S Longley R S Panush 《Annals of allergy》1987,58(3):162-3, 209-12
5.
Pallavi Parashar Anthony Musella Timothy Novak Robert O Greer 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e66-e70
Melorheostosis is a rare sclerosing bone dysplasia that is characterized by a localized, diffuse thickening of the cortical bone. This condition usually affects the appendicular skeleton and associated soft tissue and rarely affects the craniofacial complex. The etiology of this condition is obscure. Diagnosis of melorheostosis relies on clinical, radiographic, and histological correlation. Only 8 cases of melorheostosis involving the craniofacial complex have been reported. We report 2 new cases of isolated melorheostosis involving the maxilla and mandible, together with differential diagnostic considerations. To our knowledge, involvement of the maxilla only has not been previously reported. 相似文献
6.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
7.
取代四氢异喹啉衍生物的合成及其生物活性 总被引:7,自引:0,他引:7
粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ15,19对正常麻醉大鼠有一定的降压作用、Ⅳ17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α1-受体作用方式可能是形成电荷转移复合物。 相似文献
8.
9.
B G Campling A C Haworth H M Baker D L Greer J J Holden E C Bradley J Pym D F Dexter 《Cancer》1992,69(8):2064-2074
The establishment and characterization of 11 human lung cancer cell lines are described in this article. Nine of these cell lines were established over a 5-year period, from 1983 to 1988, from patients treated at the Kingston Regional Cancer Centre. These include eight definite or probable small cell lung cancer (SCLC) lines and one adenocarcinoma line. In addition, two other SCLC cell lines were characterized. All of the lines have been in continuous culture for more than 2 years. The clinical histories of the patients from whom the cell lines were derived are outlined here. Several features of the cell lines are presented, including the following: (1) a comparison of the histologic features of the cell lines with the original biopsy specimens; (2) the expression of various markers, including cytokeratin, carcinoembryonic antigen, calcitonin, and neuron-specific enolase; (3) activities of the enzymes l-dopa decarboxylase and the brain isoenzyme of creatine kinase; (4) growth characteristics; (5) cloning efficiency in soft agar; (6) tumorigenicity in nude mice; and (7) cytogenetic studies. These cell lines, obtained directly from patients with a spectrum of drug-sensitive and drug-resistant tumors, will be valuable in vitro models of sensitivity and resistance to chemotherapy in lung cancer. 相似文献
10.
Philip Harber Laura Pea Paul Hsu Elizabeth Billet Deborah Greer Katty Kim 《American journal of industrial medicine》1994,25(4):519-526
Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc. 相似文献