全文获取类型
收费全文 | 3404篇 |
免费 | 182篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 69篇 |
妇产科学 | 75篇 |
基础医学 | 376篇 |
口腔科学 | 122篇 |
临床医学 | 231篇 |
内科学 | 688篇 |
皮肤病学 | 115篇 |
神经病学 | 89篇 |
特种医学 | 171篇 |
外国民族医学 | 4篇 |
外科学 | 701篇 |
综合类 | 86篇 |
一般理论 | 2篇 |
预防医学 | 273篇 |
眼科学 | 77篇 |
药学 | 285篇 |
中国医学 | 14篇 |
肿瘤学 | 200篇 |
出版年
2024年 | 3篇 |
2023年 | 35篇 |
2022年 | 127篇 |
2021年 | 205篇 |
2020年 | 101篇 |
2019年 | 131篇 |
2018年 | 144篇 |
2017年 | 90篇 |
2016年 | 111篇 |
2015年 | 131篇 |
2014年 | 169篇 |
2013年 | 195篇 |
2012年 | 255篇 |
2011年 | 311篇 |
2010年 | 187篇 |
2009年 | 154篇 |
2008年 | 208篇 |
2007年 | 210篇 |
2006年 | 181篇 |
2005年 | 144篇 |
2004年 | 121篇 |
2003年 | 136篇 |
2002年 | 101篇 |
2001年 | 21篇 |
2000年 | 23篇 |
1999年 | 21篇 |
1998年 | 9篇 |
1997年 | 5篇 |
1996年 | 12篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1984年 | 4篇 |
1976年 | 7篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1969年 | 3篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1924年 | 1篇 |
1923年 | 1篇 |
1921年 | 1篇 |
排序方式: 共有3606条查询结果,搜索用时 2 毫秒
71.
72.
73.
74.
Khaled M. Kebaish Christopher T. Martin Joseph R. O'Brien Ivan E. LaMotta Gabor D. Voros Stephen M. Belkoff 《The spine journal》2013,13(12):1897-1903
Background contextVertebral compression fractures at the proximal junction are common complications of long spinal fusion surgeries that can contribute to the development of proximal junctional kyphosis or proximal junctional failure. To our knowledge, no biomechanical studies have addressed the effect of vertebral augmentation at the proximal junction.PurposeTo evaluate the effectiveness of prophylactic vertebroplasty in reducing the incidence of vertebral compression fractures at the proximal junction after a long spinal fusion in a cadaveric spine model.Study designBiomechanical cadaveric study.MethodsWe divided 18 cadaveric spine specimens into three groups of six spines each: a control group, a group treated with one-level prophylactic vertebroplasty at the upper instrumented vertebra, and a group treated with two-level prophylactic vertebroplasty at the upper instrumented vertebra and the supra-adjacent vertebra. In all spines, the pedicles were instrumented from L5 to T10. Using eccentric axial loading, the specimens were then compressed until failure. Failure was defined as a precipitous decrease in load with increasing compression. The effect of augmentation on load-to-failure was checked using linear regression. The effect of augmentation on incidence of adjacent fractures was checked using logistic regression. Differences at the level of p<.05 were considered significant. KyphX cement introducer was donated by Kyphon, and the pedicle screws were donated by DePuy.ResultsFractures occurred in 12 of 18 specimens: five in the control group, six in the one-level group, and only one in the two-level group; these differences were statistically significant.ConclusionsProphylactic vertebroplasty at the upper instrumented level and its supra-adjacent vertebra reduced the incidence of junctional fractures after long posterior spinal instrumentation in this axially loaded cadaveric model. Additional studies are necessary to determine if these results are translatable to clinical practice. 相似文献
75.
Mahmoud Rafaat Kandil Kawthar Abdel-Motagally Fadel Hossam Eldin Khalifa Mostafa Kamel Ghanem Khaled Osama Mohamed 《Neurological research》2013,35(3):232-241
AbstractObjectives: Headache is one of the most common complaints in medicine. Epidemiological and population-based studies reported that migraine has a variable prevalence worldwide. This study was done to estimate the prevalence of migraine across various age groups in Assiut district, Egypt.Methods: This is a door-to-door study. It included 4700 randomly selected individuals.Results: Headache was reported in 1668 subjects (35.49%), of them, 87.65% (n = 1462) had primary headaches. Migraine prevalence was 10.51% with female-to-male ratio of 2.4:1 particularly in ages of 20–40 years. The mean age of patients was 31.46 ± 13.39 years and age at onset was 24.16 ± 12.10 years. Nearly, 63.5% had frequent attacks, 65.2% of the attacks were severe enough to stop daily activities and lasted for >1 day in 32.5% of females compared to 40.7% and 14.5% for males. Chronic or daily migraine was more in females (35.3% versus 20.7% for males). Approximately, 5.6% had chronic migraine and 1.2% had daily migraine from the start, while 24.2% had transformation from episodic to chronic migraine within 6.1 ± 4.4 years. Migraine was prevalent among those with middle educational levels and labor workers. The duration of migraine attacks was found to reduce with age but the chronic/daily migraine increased with age. Hypertension, anxiety, irritable bowel syndrome, and depression were common comorbidities with migraine.Conclusions: We believe that the work done in this study is informative as it determined the actual prevalence of migraine across various age groups and the important predictors of change in the severity, duration, and frequency of migraine in our locality. 相似文献
76.
77.
78.
79.
80.