全文获取类型
收费全文 | 8797篇 |
免费 | 533篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 93篇 |
儿科学 | 332篇 |
妇产科学 | 211篇 |
基础医学 | 903篇 |
口腔科学 | 353篇 |
临床医学 | 717篇 |
内科学 | 2015篇 |
皮肤病学 | 164篇 |
神经病学 | 516篇 |
特种医学 | 195篇 |
外国民族医学 | 2篇 |
外科学 | 1419篇 |
综合类 | 368篇 |
一般理论 | 18篇 |
预防医学 | 476篇 |
眼科学 | 267篇 |
药学 | 710篇 |
中国医学 | 117篇 |
肿瘤学 | 517篇 |
出版年
2024年 | 9篇 |
2023年 | 107篇 |
2022年 | 294篇 |
2021年 | 449篇 |
2020年 | 242篇 |
2019年 | 293篇 |
2018年 | 362篇 |
2017年 | 183篇 |
2016年 | 265篇 |
2015年 | 345篇 |
2014年 | 382篇 |
2013年 | 467篇 |
2012年 | 682篇 |
2011年 | 769篇 |
2010年 | 369篇 |
2009年 | 337篇 |
2008年 | 529篇 |
2007年 | 492篇 |
2006年 | 470篇 |
2005年 | 428篇 |
2004年 | 381篇 |
2003年 | 307篇 |
2002年 | 319篇 |
2001年 | 119篇 |
2000年 | 80篇 |
1999年 | 84篇 |
1998年 | 52篇 |
1997年 | 47篇 |
1996年 | 42篇 |
1995年 | 41篇 |
1994年 | 32篇 |
1993年 | 26篇 |
1992年 | 39篇 |
1991年 | 35篇 |
1990年 | 29篇 |
1989年 | 29篇 |
1988年 | 25篇 |
1987年 | 16篇 |
1986年 | 21篇 |
1985年 | 13篇 |
1984年 | 16篇 |
1983年 | 24篇 |
1982年 | 19篇 |
1981年 | 15篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1977年 | 11篇 |
1976年 | 11篇 |
1975年 | 12篇 |
1974年 | 11篇 |
排序方式: 共有9393条查询结果,搜索用时 15 毫秒
1.
Objectives
Iatrogenic injury of the Profunda Femoris Artery (PFA) at time of hip fixation surgery can increase morbidity and mortality and prolong the hospital stay. This is an injury that tends to pass unnoticed as a cause of postoperative deterioration despite being frequently reported in the literature. Our study aims to describe the anatomy of the PFA in relation to the medial femoral cortex with specific emphasis on its orientation relative to the position of a sliding hip screw side plate construct. By doing so we are able to present clear guidance to orthopaedic surgeons on how to avoid iatrogenic PFA injury at the time of hip fracture fixation.Methods
Using Computed Tomography Angiographic (CTA) studies, the course of the PFA in relation to the medial femoral cortex was traced in 44 patients (28 males and 16 females) with mean age of 65.6 years. Coronal and axial CT sections were cross-linked to specify the position of the PFA at 1?cm intervals.Results
The course of the artery could be divided into three parts relative to a fixed reference point. Proximal and distal parts of the artery were in a safer position in comparison to the middle part of the artery that was found very close to the femoral cortex and along the coronal axis of the femur (mean angle 2.9° from the femoral coronal axis and 13.8?mm from the medial femoral cortex). Using the commercially available side plate constructs, this part of the artery corresponded to the distal part of the plate (third and fourth holes).Conclusion
Special attention needs to be practiced by the operating surgeon while drilling into the third and fourth holes of the side plate. 相似文献2.
Andrea DiMartini Nancy Day Mary Amanda Dew Lubna Javed Mary Grace Fitzgerald Ashok Jain John J Fung Paulo Fontes 《Liver transplantation》2006,12(5):813-820
For patients who receive a liver transplant (LTX) for alcoholic liver disease (ALD), investigators are focusing beyond survival to determine specific alcohol use outcomes. Studies suggest the use of alcohol ranges from 8 to 22% for the first post-transplant year with cumulative rates reaching 30 to 40% by 5 years following transplantation. Yet while investigators are interested in determining specific rates of alcohol use and predictors of use, only three studies since 1990 have been prospective. In 1998, we began a prospective study of post-LTX alcohol consumption in ALD recipients using multiple repeated measures of alcohol use. After 5 years of follow-up, we found that 22% had used any alcohol by the first year and 42% had a drink by 5 years. By 5 years, 26% drank at a heavier use (binge) pattern and 20% drank in a frequent pattern. In a univariate model, predictors of alcohol use included pre-transplant length of sobriety, a diagnosis of alcohol dependence, a history of other substance use, and prior alcohol rehabilitation. 相似文献
3.
4.
Michael Hutchinson Jonathon O'Riordan Mohammed Javed Etain Quin Donal Macerlaine Teresa Willcox Nollaig Parfrey Tamas G. Nagy Elisabeth Tournier-Lasserve 《Annals of neurology》1995,38(5):817-824
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently described familial cerebrovascular disorder shown to map to chromosome 19q12. Familial hemiplegic migraine has also been shown in some families to map close to the CADASIL locus. The fully developed CADASIL phenotype consists of recurrent strokes developing in the fourth decade, progressing to a pseudobulbar palsy, spastic quadriparesis, and subcortical dementia. In an Irish family 15 members were fully investigated by magnetic resonance scanning; 10 had typical magnetic resonance features of CADASIL. Five members of this family had familial hemiplegic migraine and 4 of these had magnetic resonance evidence of CADASIL. Two other members had migraine with and without aura as a presenting clinical symptom of CADASIL. This disorder has been shown by linkage analysis to map to the CADASIL locus at chromosome 19. The phenotype at presentation of CADASIL in this family was variable and age related and included familial hemiplegic migraine, migraine with and without aura, transient ischemic attacks, strokes, and spinal cord infarction. This family study increases our understanding of the spectrum of clinical manifestations of this underrecognized familial cerebrovascular disorder. 相似文献
5.
A. Rashid Choudhury Mohamed S. Al Amin Kamal A. Chaudhri Khalaf R. Al Moutaery 《Child's nervous system》1995,11(2):115-117
A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma. 相似文献
6.
M. Perwaiz Iqbal M. Khalid Ashfaq Sarfaraz K. Niazi M. Mahboobali Khalid N. Khawaja 《Biopharmaceutics & drug disposition》1994,15(2):173-177
Pharmacokinetic parameters of two antifolates, trimethoprim and aditoprim, were studied in buffalo calves. The elimination half-life of aditoprim (6.14 h) was nearly twice as long as that of trimethoprim (3.08 h) and compares well with values observed in heifers. This longer half-life of aditoprim is a result of its much larger distribution volume (four to five times larger) because the clearance of aditoprim was about twice as high as that of trimethoprim. The longer half-life of aditoprim is expected to give a longer duration of in vivo bacteriostatic activity than that of trimethoprim. 相似文献
7.
8.
Normal cerebral perfusion measurements using arterial spin labeling: reproducibility, stability, and age and gender effects. 总被引:4,自引:0,他引:4
Laura M Parkes Waqar Rashid Declan T Chard Paul S Tofts 《Magnetic resonance in medicine》2004,51(4):736-743
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males. 相似文献
9.
Khalid Irshad Samuel Millar Raj Velu Allan W Reid Edward B Diethrich Donald B Reid 《Journal of endovascular therapy》2007,14(2):198-207
PURPOSE: To report early clinical experience with virtual histology intravascular ultrasound (VH IVUS) in carotid endoluminal repair. TECHNIQUE: A 2.9-F, 20-MHz catheter that utilizes computer software to demonstrate the histological components of arteriosclerotic plaque was evaluated during carotid angioplasty and stenting. VH IVUS images were created following a pullback through the carotid stenosis and produced a color-coded map of the different histological constituents of the disease (dark green: fibrous, yellow/green: fibrofatty, white: calcified, and red: necrotic lipid core plaque). CONCLUSION: VH IVUS produces a color-coded map of the different histological components of artery plaque. It has the potential to predict how the plaque is likely to behave at the moment of endoluminal treatment. 相似文献
10.
Ahmed M. Abu El-Asrar Eman S. Kahtani Khalid F. Tabbara 《Documenta ophthalmologica. Advances in ophthalmology》1995,89(4):313-320
In this report we describe, herewith, a patient with primary pigmentary dystrophy of the retina (retinitis pigmentosa) associated with unilateral retinal arteriovenous communication and exudative retinal detachment. The patient had complete resolution of the retinal detachment following laser photocoagulation treatment. Such association has not been previously reported. 相似文献