全文获取类型
收费全文 | 676篇 |
免费 | 34篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 55篇 |
妇产科学 | 3篇 |
基础医学 | 65篇 |
口腔科学 | 15篇 |
临床医学 | 126篇 |
内科学 | 135篇 |
皮肤病学 | 21篇 |
神经病学 | 10篇 |
特种医学 | 140篇 |
外科学 | 47篇 |
综合类 | 9篇 |
预防医学 | 9篇 |
眼科学 | 5篇 |
药学 | 44篇 |
肿瘤学 | 28篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 7篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 11篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 13篇 |
2014年 | 11篇 |
2013年 | 17篇 |
2012年 | 11篇 |
2011年 | 16篇 |
2010年 | 26篇 |
2009年 | 24篇 |
2008年 | 17篇 |
2007年 | 11篇 |
2006年 | 20篇 |
2005年 | 15篇 |
2004年 | 14篇 |
2003年 | 13篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 13篇 |
1998年 | 37篇 |
1997年 | 48篇 |
1996年 | 47篇 |
1995年 | 42篇 |
1994年 | 19篇 |
1993年 | 22篇 |
1992年 | 13篇 |
1991年 | 18篇 |
1990年 | 8篇 |
1989年 | 17篇 |
1988年 | 28篇 |
1987年 | 22篇 |
1986年 | 23篇 |
1985年 | 14篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1981年 | 14篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 8篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 9篇 |
1974年 | 1篇 |
排序方式: 共有714条查询结果,搜索用时 390 毫秒
41.
Nystedt JM Lemberg K Lintunen M Mustonen K Holma R Kontinen VK Kalso E Panula P 《Neurobiology of disease》2004,16(1):254-262
Neuropeptide FF (NPFF) is involved in pain modulation, especially plasticity during inflammatory and neuropathic pain, and opiate interactions. Its nociceptive functions may be mediated by the NPFF2 receptor. To elucidate the role of the NPFF system in plasticity associated with pathologic pain, we studied the changes of NPFF mRNA and NPFF2 receptor mRNA in rat models of acute colonic inflammation, inflammatory pain, and neuropathic pain. Furthermore, we studied the mRNA levels of both NPFF and NPFF2 receptor in morphine-tolerant rats and after acute morphine injections. We found an activation of spinal NPFF and NPFF2 receptor during early inflammatory pain. Supraspinally, we found an up-regulation of NPFF2 receptor mRNA during acute colonic inflammation and neuropathic pain. Acute, but not chronic, morphine activated the genes supraspinally. The results give further evidence for the involvement of the NPFF system in pain modulation and may provide new therapeutic opportunities for pathologic pain. 相似文献
42.
43.
Hanks GW Conno F Cherny N Hanna M Kalso E McQuay HJ Mercadante S Meynadier J Poulain P Ripamonti C Radbruch L Casas JR Sawe J Twycross RG Ventafridda V;Expert Working Group of the Research Network of the European Association for Palliative Care 《British journal of cancer》2001,84(5):587-593
An expert working group of the European Association for Palliative Care has revised and updated its guidelines on the use of morphine in the management of cancer pain. The revised recommendations presented here give guidance on the use of morphine and the alternative strong opioid analgesics which have been introduced in many parts of the world in recent years. Practical strategies for dealing with difficult situations are described presenting a consensus view where supporting evidence is lacking. The strength of the evidence on which each recommendation is based is indicated. 相似文献
44.
Ciprofloxacin, given to a patient successfully treated with methadone for more than 6 years, caused profound sedation, confusion, and respiratory depression. We suggest that this was caused by ciprofloxacin inhibition of CYP1A2 and CYP3A4 activity, two of the cytochrome p450 isozymes involved in the metabolism of methadone. 相似文献
45.
DP Southall WA Arrowsmith JR Oakley G McEnery RH Anderson EA Shinebourne 《Archives of disease in childhood》1979,54(10):776-779
Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS. 相似文献
46.
47.
Magill HL; Clarke EA; Fitch SJ; Boulden TF; Ramirez R; Siegle RL; Somes GW 《Radiology》1986,161(3):625-630
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent. 相似文献
48.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献
49.
50.
Myocardial tagging in polar coordinates with use of striped tags 总被引:1,自引:0,他引:1
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle. 相似文献