全文获取类型
收费全文 | 1264篇 |
免费 | 81篇 |
国内免费 | 10篇 |
专业分类
儿科学 | 74篇 |
妇产科学 | 11篇 |
基础医学 | 114篇 |
口腔科学 | 20篇 |
临床医学 | 138篇 |
内科学 | 295篇 |
皮肤病学 | 14篇 |
神经病学 | 77篇 |
特种医学 | 221篇 |
外科学 | 161篇 |
综合类 | 12篇 |
预防医学 | 64篇 |
眼科学 | 9篇 |
药学 | 77篇 |
中国医学 | 2篇 |
肿瘤学 | 66篇 |
出版年
2022年 | 7篇 |
2021年 | 7篇 |
2020年 | 9篇 |
2018年 | 10篇 |
2017年 | 8篇 |
2016年 | 14篇 |
2015年 | 17篇 |
2014年 | 27篇 |
2013年 | 31篇 |
2012年 | 44篇 |
2011年 | 48篇 |
2010年 | 26篇 |
2009年 | 33篇 |
2008年 | 49篇 |
2007年 | 36篇 |
2006年 | 40篇 |
2005年 | 42篇 |
2004年 | 40篇 |
2003年 | 30篇 |
2002年 | 34篇 |
2001年 | 41篇 |
2000年 | 29篇 |
1999年 | 27篇 |
1998年 | 48篇 |
1997年 | 67篇 |
1996年 | 49篇 |
1995年 | 39篇 |
1994年 | 40篇 |
1993年 | 34篇 |
1992年 | 22篇 |
1991年 | 24篇 |
1990年 | 13篇 |
1989年 | 27篇 |
1988年 | 35篇 |
1987年 | 31篇 |
1986年 | 39篇 |
1985年 | 30篇 |
1984年 | 25篇 |
1983年 | 16篇 |
1982年 | 17篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 13篇 |
1977年 | 15篇 |
1976年 | 7篇 |
1975年 | 12篇 |
1972年 | 10篇 |
1970年 | 7篇 |
1969年 | 11篇 |
排序方式: 共有1355条查询结果,搜索用时 15 毫秒
1.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
2.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
3.
4.
5.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
6.
J C Bousquet A Goze M Hassan E Kieffer P Curet J Grellet 《Journal of ultrasound in medicine》1987,6(1):7-12
Ultrasonographic features of six leiomyosarcomas of the inferior vena cava are described. In most cases, the presentation is typical enough to strongly suggest the histologic diagnosis. The tumor is usually greater than 10 cm long, hypoechoic, heterogeneous. Cystic components can be found. It is sharply demarcated from neighboring organs which are displaced. The mass is located at the very place of the inferior vena cava, the lumen of which is no longer seen. It is fusiform shaped, surprisingly sparing the aorta. Differential diagnosis along with other radiologic examinations, pathologic findings, and prognosis are discussed. 相似文献
7.
Esophageal candidosis in progressive systemic sclerosis: occurrence, significance, and treatment with fluconazole 总被引:1,自引:0,他引:1
L Hendel E Svejgaard I Wals?e M Kieffer A Stenderup 《Scandinavian journal of gastroenterology》1988,23(10):1182-1186
Esophageal mucosal brushings from 51 consecutive patients with progressive systemic sclerosis (PSS) (group I), 18 PSS patients continuously treated with high-dose ranitidine or omeprazole (group II), 34 controls referred to the outpatient clinic for endoscopy (group III), and 10 patients receiving long-term potent antireflux therapy for idiopathic gastroesophageal reflux (group IV) were cultured for Candida albicans. There were 44%, 89%, 9%, and 0% Candida albicans culture-positive patients in groups I through IV, respectively. Fifteen patients with candida esophagitis from group II were treated with fluconazole systemically. Eleven and 14 patients became culture-negative after 2 and 4 weeks' treatment, respectively. Three months after fluconazole withdrawal the recurrence rate was 100%. It is concluded that esophageal dysmotility predisposes for candidosis. Adding gastric acid inhibitory treatment to dysmotility enhances the risk significantly (p less than 0.01). The efficiency of fluconazole treatment was close to 100%, but so was the recurrence rate within a short period. 相似文献
8.
9.
10.
J D Tempé J J Muller J Schieber M Hasselmann P Lutun P Kieffer F Schneider 《Revue de pneumologie clinique》1987,43(6):300-305
From a series of 50 patients with acute decompensation of chronic obstructive lung disease (38 of whom were treated by mechanical ventilation), the authors demonstrate the prognostic value of an easily obtained parameter of respiratory function: the vital capacity restitution curve (VCRC). From daily measurements of vital capacity, beginning on the day of admission, a graph is constructed which shows an initial period of increase in the degree of restitution, followed by stabilization of the values. An analysis of the various parameters embodied in this graph provides information about the prognosis. Such graphs can be divided into 3 zones of prognostic value: a favourable zone, an intermediate zone (mediocre survival with or without mechanical ventilation) and an unfavourable zone (death during the acute phase). Although a favourable prognosis can be made after 4 days of observation and almost always by the 10th day, an unfavourable prognosis cannot be made before the 21st day. 相似文献