全文获取类型
收费全文 | 1009篇 |
免费 | 63篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 65篇 |
妇产科学 | 6篇 |
基础医学 | 130篇 |
口腔科学 | 15篇 |
临床医学 | 118篇 |
内科学 | 278篇 |
皮肤病学 | 6篇 |
神经病学 | 20篇 |
特种医学 | 149篇 |
外科学 | 102篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 63篇 |
眼科学 | 15篇 |
药学 | 56篇 |
中国医学 | 2篇 |
肿瘤学 | 40篇 |
出版年
2021年 | 8篇 |
2020年 | 9篇 |
2019年 | 11篇 |
2018年 | 6篇 |
2017年 | 9篇 |
2016年 | 9篇 |
2015年 | 15篇 |
2014年 | 15篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 34篇 |
2010年 | 19篇 |
2009年 | 22篇 |
2008年 | 24篇 |
2007年 | 30篇 |
2006年 | 26篇 |
2005年 | 31篇 |
2004年 | 20篇 |
2003年 | 27篇 |
2002年 | 21篇 |
2001年 | 15篇 |
2000年 | 16篇 |
1999年 | 14篇 |
1998年 | 42篇 |
1997年 | 64篇 |
1996年 | 42篇 |
1995年 | 34篇 |
1994年 | 34篇 |
1993年 | 26篇 |
1992年 | 35篇 |
1991年 | 23篇 |
1990年 | 18篇 |
1989年 | 37篇 |
1988年 | 30篇 |
1987年 | 39篇 |
1986年 | 38篇 |
1985年 | 33篇 |
1984年 | 18篇 |
1983年 | 12篇 |
1982年 | 18篇 |
1981年 | 7篇 |
1980年 | 12篇 |
1979年 | 5篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 11篇 |
1975年 | 13篇 |
1974年 | 10篇 |
1972年 | 8篇 |
1971年 | 5篇 |
排序方式: 共有1082条查询结果,搜索用时 62 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.
Between 1979 and 1988 43 percutaneous transluminal angioplasties (PTA) of the deep femoral artery were performed for treatment of severe claudication (n = 15) or for limb salvage (n = 28). Ateriographically, all patients had a long occlusion of the superficial femoral artery. Additional PTA of significant obstructions in the iliac and common femoral artery were performed in 6 patients of each group. Technical success was achieved in 41 of the 43 procedures (95%). Early clinical success was 60% for claudicants and 68% for patients with limb threatening ischemia. Success rates tended to be higher if additional PTA of the inflow tract was performed (75% versus 61%, n.s.). Patient with a good distal outflow benefited more frequently from PTA if they were treated for limb salvage (p less than 0.05). Within a follow-up period up to 24 months (mean 18.0 months) 5 patients died and one late failure occurred. Life table analysis lasting success in patients dilated for limb salvage, whereas success rate decreased to 48% in claudicants. PTA of the deep femoral artery is a less invasive and efficient treatment particularly for patients with limb threatening ischemia, an appropriate obstruction morphology provided. 相似文献
4.
5.
6.
Prof. Dr. Bollinger 《Virchows Archiv : an international journal of pathology》1873,58(3-4):329-348
Ohne Zusammenfassung 相似文献
7.
Kim Mudd Mary Elizabeth Bollinger Van Doren Hsu Michele Donithan Arlene Butz 《The Journal of asthma》2006,43(8):597-600
Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications. 相似文献
8.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
9.
A pattern of enlarged capillaries densely packed with red cells and not filled by the intravital dye Na-fluorescein for 10-20 min is described. Probably it corresponds to microvascular thrombosis. Alternative explanations like prolonged stasis appear unlikely. Up to now the pattern has been detected in severe chronic venous incompetence, collagen vascular disease and essential thrombocytosis. 相似文献
10.