全文获取类型
收费全文 | 10409篇 |
免费 | 1100篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 184篇 |
儿科学 | 409篇 |
妇产科学 | 219篇 |
基础医学 | 1315篇 |
口腔科学 | 131篇 |
临床医学 | 1118篇 |
内科学 | 1820篇 |
皮肤病学 | 447篇 |
神经病学 | 1051篇 |
特种医学 | 380篇 |
外科学 | 1440篇 |
综合类 | 319篇 |
现状与发展 | 30篇 |
一般理论 | 5篇 |
预防医学 | 1278篇 |
眼科学 | 145篇 |
药学 | 696篇 |
中国医学 | 7篇 |
肿瘤学 | 545篇 |
出版年
2023年 | 206篇 |
2021年 | 115篇 |
2020年 | 121篇 |
2019年 | 131篇 |
2018年 | 180篇 |
2017年 | 168篇 |
2016年 | 132篇 |
2015年 | 166篇 |
2014年 | 267篇 |
2013年 | 344篇 |
2012年 | 348篇 |
2011年 | 389篇 |
2010年 | 278篇 |
2009年 | 281篇 |
2008年 | 416篇 |
2007年 | 524篇 |
2006年 | 427篇 |
2005年 | 380篇 |
2004年 | 375篇 |
2003年 | 371篇 |
2002年 | 362篇 |
2001年 | 345篇 |
2000年 | 415篇 |
1999年 | 340篇 |
1998年 | 182篇 |
1997年 | 138篇 |
1996年 | 143篇 |
1995年 | 138篇 |
1994年 | 124篇 |
1993年 | 125篇 |
1992年 | 277篇 |
1991年 | 225篇 |
1990年 | 262篇 |
1989年 | 227篇 |
1988年 | 226篇 |
1987年 | 203篇 |
1986年 | 178篇 |
1985年 | 212篇 |
1984年 | 132篇 |
1983年 | 92篇 |
1982年 | 106篇 |
1981年 | 79篇 |
1980年 | 82篇 |
1979年 | 116篇 |
1978年 | 105篇 |
1977年 | 79篇 |
1976年 | 102篇 |
1975年 | 89篇 |
1974年 | 96篇 |
1973年 | 93篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
42.
W F Tatu W S Holmes W C Black R Mainwaring T Carter 《The Journal of computed tomography》1988,12(1):32-35
We report the imaging findings of an abdominal aggressive angiomyxoma, which communicated with the gastrointestinal tract. The literature on this rare tumor is reviewed. 相似文献
43.
Lincoln C. L. Lee Ian W. Black rew Hopkins Warren F. Walsh 《Internal medicine journal》1992,22(5):527-531
Cardiac ultrasound and upper gastrointestinal endoscopy are relatively old technologies. With the introduction of new ultrasound probes and by incorporating ultrasound technology into conventional endoscopes, ‘new tricks’ in cardiac imaging were discovered. Posterior structures of the heart are now able to be imaged clearly by the ultrasound probe from the oesophagus. Consequently, better resolution of cardiac anatomy allows more accurate diagnosis of cardiac pathologies which is not possible using conventional transthoracic (TT) approach. Over a period of two years, 1200 cases of transoesophageal echocardiography (TOE) were undertaken in our institution. The major indications were diseases of the aorta (10%), source of cardioembolism (28%), assessment of native and prosthetic valve function (20%), suspected endocarditis and its complication (17%), pre and post percutaneous transluminal mitral valvotomy (PTMV [13%], congenital heart disease (2%) and others (10%). The greatest impact with TOE is in the diagnosis of aortic dissection and transection, TOE is superior to conventional TT approach in detecting potential source of embolism, valvular vegetations and its complication, native and prosthetic valve dysfunction and LA thrombus prior to PTMV. Observations by TOE such as spontaneous echo contrast (SEC) in the left atrium open new challenges for further research in its role in the pathogenesis of LA thrombus and its association with cardioembolic event. Other areas of interest include; reclassification of distal aortic dissection and the use of TOE in intra-operative work. 相似文献
44.
45.
Spinal cords of myelin-deficient and normal age-matched (control) rats were removed and their conduction and pharmacological properties studied in an in vitro brain slice chamber. The conduction velocity of the myelin-deficient dorsal column axons was reduced to about 25% of control axons; however, the amyelinated myelin-deficient axons displayed refractory periods and the ability to sustain high-frequency action potential discharge similar to that of dorsal column axons in control rats. Pharmacological results suggest that the myelin-deficient dorsal column axons qualitatively express a normal complement of ion channels and receptors. The demonstration of a normal representation of channels and receptors on these axons supports the proposal that the oligodendrocyte, and not the axon, is the site of the primary defect in the myelin-deficient rat mutant. It is concluded that, unlike acutely demyelinated axons which display marked frequency-dependent conduction block, amyelinated axons of the myelin-deficient rat spinal cord develop compensatory mechanisms to stabilize action potential conduction. 相似文献
46.
Judith L. Black Peter R. A. Johnson Lorraine Alouan Carol L. Armour 《European journal of pharmacology》1990,180(2-3):311-317
This study investigated the effects of neurokinin A (NKA) on cholinergic neural responses in human bronchus. NKA (0.1 nM) did not alter the contractile response to submaximal electrical field stimulation. However, K+ channel blockade with 4-aminopyridine (4-AP) (0.1 mM) potentiated the response to electrical field stimulation (to 182 ± 25% of control, n = 4, P < 0.05) and subsequent addition of NKA in the presence of 4-AP produced further potentiation (to 123 ± 6% of the response to 4-AP n = 4, P < 0.05). Neither 4-AP (0.01 or 0.1 mM) nor NKA in the presence of 4-AP potentiated the actions of exogenous acetylcholine but in these experiments 4-AP itself produced a marked direct contractile response. Thus NKA in the presence of K+ channel blockade potentiates cholinergic neural response in human bronchus and this occurs at a prejunctional site. 相似文献
47.
P. Kalina K. E. Drehobl K. Black R. Woldenberg M. Sapan 《Postgraduate medical journal》1995,71(836):378-379
A woman with an eight-year history of polycythemia vera presented with numbness and weakness of both legs. A large spinal haematoma was revealed on magnetic resonance imaging which was treated clinically and which subsequently resolved. 相似文献
48.
49.
Prevalence of hallucinations and delusions was studied in 1,763 patients with unipolar major depression, bipolar affective disorder, and schizoaffective disorder. The authors found that the presence of psychotic features was negatively associated with age of onset for the group as a whole, and bipolar affective disorder (manic or mixed type) specifically. The clinical implications of the findings are discussed. 相似文献
50.
High resolution computed tomography as a predictor of lung histology in systemic sclerosis 总被引:2,自引:0,他引:2 下载免费PDF全文
A U Wells D M Hansell B Corrin N K Harrison P Goldstraw C M Black R M du Bois 《Thorax》1992,47(7):508-512
Background The relative proportions of fibrosis and inflammation seen by open lung biopsy examination is a predictor of disease outcome in fibrosing alveolitis. This study was designed to assess the ability of high resolution computed tomography to predict the histological appearance of open lung biopsy specimens from patients with systemic sclerosis. 相似文献