全文获取类型
收费全文 | 1688篇 |
免费 | 106篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 82篇 |
妇产科学 | 69篇 |
基础医学 | 251篇 |
口腔科学 | 40篇 |
临床医学 | 210篇 |
内科学 | 299篇 |
皮肤病学 | 32篇 |
神经病学 | 105篇 |
特种医学 | 214篇 |
外国民族医学 | 1篇 |
外科学 | 156篇 |
综合类 | 36篇 |
预防医学 | 112篇 |
眼科学 | 17篇 |
药学 | 124篇 |
中国医学 | 1篇 |
肿瘤学 | 39篇 |
出版年
2023年 | 5篇 |
2022年 | 11篇 |
2021年 | 25篇 |
2020年 | 17篇 |
2019年 | 37篇 |
2018年 | 26篇 |
2017年 | 30篇 |
2016年 | 24篇 |
2015年 | 33篇 |
2014年 | 42篇 |
2013年 | 58篇 |
2012年 | 60篇 |
2011年 | 63篇 |
2010年 | 39篇 |
2009年 | 49篇 |
2008年 | 78篇 |
2007年 | 70篇 |
2006年 | 73篇 |
2005年 | 60篇 |
2004年 | 45篇 |
2003年 | 63篇 |
2002年 | 55篇 |
2001年 | 40篇 |
2000年 | 43篇 |
1999年 | 53篇 |
1998年 | 49篇 |
1997年 | 58篇 |
1996年 | 47篇 |
1995年 | 48篇 |
1994年 | 29篇 |
1993年 | 31篇 |
1992年 | 33篇 |
1991年 | 37篇 |
1990年 | 27篇 |
1989年 | 32篇 |
1988年 | 31篇 |
1987年 | 38篇 |
1986年 | 28篇 |
1985年 | 27篇 |
1984年 | 19篇 |
1983年 | 12篇 |
1982年 | 24篇 |
1981年 | 16篇 |
1980年 | 22篇 |
1979年 | 10篇 |
1978年 | 16篇 |
1977年 | 27篇 |
1976年 | 16篇 |
1975年 | 10篇 |
1973年 | 4篇 |
排序方式: 共有1808条查询结果,搜索用时 15 毫秒
1.
2.
R Matorras J Diez M Saez F Montoya G Aranguren F J Rodríguez-Escudero 《International journal of gynaecology and obstetrics》1991,36(4):323-327
Two pregnancies in a patient with a fixed-rate pacemaker are reported. The first pregnancy was uneventful. The second had no maternal complications either. A moderate tachysystolia was detected during the second period. The newborn was delivered with forceps applied under spinal anesthesia. Newborn infant evolution presented no hazards, but umbilical cord analysis revealed a severe acidosis, in spite of a normal scalp analysis 45 min earlier. Epidural anesthesia is recommended for such patients. 相似文献
3.
Three dimensional computed tomography was performed in 150 children suffering from a bone lesion of the base of the skull and face. These lesions were either malformative, neoplastic, infectious or traumatic. 3D CT provided an essential anatomical approach to the lesions facilitating the choice of the most appropriate treatment. 3D CT is also indicated in the follow-up of these operated children, particularly of the growth of the operated bone segment and its relations with adjacent structures. 相似文献
4.
5.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
6.
7.
Localised agenesis of the scalp is the most frequent patern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20% of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment. 相似文献
8.
导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12). 相似文献
9.
10.
Detection of St. Louis encephalitis virus antigen in mosquitoes by capture enzyme immunoassay. 总被引:1,自引:4,他引:1 下载免费PDF全文
T F Tsai R A Bolin M Montoya R E Bailey D B Francy M Jozan J T Roehrig 《Journal of clinical microbiology》1987,25(2):370-376
Surveillance methods that measure St. Louis encephalitis (SLE) virus activity in nature may provide forewarning of its epidemic occurrence in humans. An antigen capture enzyme immunoassay was developed to detect SLE virus in infected mosquitoes. The assay detected purified SLE viral antigen at a concentration of 62 pg/0.1 ml when antigen was incubated overnight; 250 pg/0.1 ml was detected in a single-day assay (antigen incubated for 3 h). The assay detected 67.9 and 70.8% of laboratory-prepared pools of infected mosquitoes after 3 h and overnight incubation, respectively. The sensitivity of the procedure was 90.5% in identifying pools with infectious titers greater than dex 3.0. The specificity of the assay was controlled by retesting positive pools preincubated with SLE virus and normal antibodies, which led to a diminution of signal in the pools containing viral antigen. The procedure was suitably specific in discriminating between SLE and related flaviviruses, detecting only high infectious doses of heterologous antigens. 相似文献