全文获取类型
收费全文 | 1994篇 |
免费 | 157篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 41篇 |
妇产科学 | 51篇 |
基础医学 | 232篇 |
口腔科学 | 54篇 |
临床医学 | 236篇 |
内科学 | 405篇 |
皮肤病学 | 30篇 |
神经病学 | 140篇 |
特种医学 | 81篇 |
外国民族医学 | 1篇 |
外科学 | 268篇 |
综合类 | 24篇 |
一般理论 | 1篇 |
预防医学 | 178篇 |
眼科学 | 65篇 |
药学 | 122篇 |
中国医学 | 2篇 |
肿瘤学 | 202篇 |
出版年
2023年 | 8篇 |
2022年 | 11篇 |
2021年 | 40篇 |
2020年 | 34篇 |
2019年 | 44篇 |
2018年 | 56篇 |
2017年 | 27篇 |
2016年 | 45篇 |
2015年 | 46篇 |
2014年 | 68篇 |
2013年 | 102篇 |
2012年 | 103篇 |
2011年 | 133篇 |
2010年 | 77篇 |
2009年 | 53篇 |
2008年 | 131篇 |
2007年 | 117篇 |
2006年 | 116篇 |
2005年 | 101篇 |
2004年 | 120篇 |
2003年 | 92篇 |
2002年 | 98篇 |
2001年 | 46篇 |
2000年 | 30篇 |
1999年 | 21篇 |
1998年 | 21篇 |
1997年 | 12篇 |
1996年 | 15篇 |
1995年 | 15篇 |
1994年 | 12篇 |
1993年 | 12篇 |
1992年 | 20篇 |
1991年 | 30篇 |
1990年 | 22篇 |
1989年 | 27篇 |
1988年 | 22篇 |
1987年 | 14篇 |
1986年 | 11篇 |
1985年 | 14篇 |
1984年 | 16篇 |
1983年 | 18篇 |
1982年 | 9篇 |
1981年 | 9篇 |
1980年 | 15篇 |
1978年 | 20篇 |
1975年 | 10篇 |
1971年 | 7篇 |
1970年 | 7篇 |
1969年 | 7篇 |
1966年 | 6篇 |
排序方式: 共有2153条查询结果,搜索用时 265 毫秒
1.
Omar P. Sangüeza Julie K. Salmon Clifton R. White Jr. Jay H. Beckstead 《Journal of cutaneous pathology》1995,22(4):327-335
Juvenile xanthogranuloma (JXC) is a benign histiocylic proliferation of uncertain histogenesis which usually resolves spontaneously. Histopathologically, classic lesions are characterized by diffuse proliferations of foamy histiocytes, many of which may be multinucleated (Toulon cells), admixed with lymphocytes and eosinophils. Histologic variants of JXG, perhaps representing evolving lesions, may lack these typical histopathological features, showing diffuse infiltrates of non-foamy mononuclear histiocytes without Toulon cells, posing problems in differentiation from other histiocylic or melanocylic proliferations. Immunohistochemically, JXG is characterized by variable expressions of several histiocytic markers as well as the absence of staining for SI00 protein. To assess better the spectrum of histopathological and immunohistochemical features of JXG, we studied nine cases of classic or histologic variant of JXG. The cases were evaluated by light microscopy and with an extensive battery of antibodies. All 9 cases, regardless of their light microscopic appearance, showed markedly positive staining with histiocytic markers including CD68, HAM56, cathepsin B and vimentin, but did not stain for S100 protein. Antibodies to factor XIIIa stained positively in 8 cases while staining for other markers was variable. Our results suggest that the histiocytes in JXG lesions have macrophagic differentiation, probably representing a reactive process to an unknown stimulus. 相似文献
2.
I.J. Clifton A.M. Morton N.S. Ambrose D.G. Peckham S.P. Conway 《Journal of cystic fibrosis》2004,3(4):273-275
We report a case of a patient with CF who had a long history of recurrent distal intestinal obstruction syndrome. She had been treated with conventional treatment including gastrografin, n-acetyl cysteine, Klean prep and Picolax. She underwent a modified antegrade continence enema procedure. She currently irrigates her conduit every 2-3 days. She has had no further symptoms of distal intestinal obstruction syndrome. 相似文献
3.
Clifton M. Schor James S. Maxwell Scott B. Stevenson 《Ophthalmic & physiological optics》1994,14(3):279-286
Conjugate gaze is often defined as the equal angle rotation of the two eyes. For fixation at far distances, the optical axes are parallel and conjugacy is defined irrespective of the coordinate system. For nearby or finite fixation distances, the evaluation of conjugacy for many gaze postures depends on the coordinate system used to measure it. For example, if the eye is elevated or depressed and the eye is rotated about a vertical axis, the intersections of lines of sight with a tangent screen will describe either straight lines for arcs depending on whether the vertical axis is fixed with respect to the head or to the eye. Because of the horizontal separation of the two eyes, the binocular fixation of near targets at tertiary positions of gaze will require a vertical vergence component for head-referenced but not eye-referenced measurements. The vertical gaze alignment of three human subjects was measured as they viewed targets placed at secondary and tertiary eye positions at two different distances. Vertical vergence was either held open or closed-loop. The lines of sight were found lo intersect (i.e. vertical gaze was aligned) regardless of target position or viewing condition. 相似文献
4.
采用Barthel指数对120例脑卒中住院患者在发病后5 ̄6周进行日常生活活动(ADL)能力的证实。因脑卒中遗留的功能不全,ADL的受损率达66.7%,肢体的Brunnstrom功能分级与ADL积分高度相关,相关性下肢高于上肢;多元逐步回归分析显示,躯体(偏瘫)和心理(认知障碍和抑郁因素)影响ADL的能力。认为ADL能力的提高,不仅依赖于肢体功能障碍的改善,提高认知功能,改善情感状况,对于脑卒中患 相似文献
5.
Appearances of posterior osteophytes after sound anterior interbody fusion in the cervical spine: a high-definition computed myelographic study 总被引:1,自引:0,他引:1
Summary Whether posterior osteophytes in the cervical spine resorb after anterior interbody fusion is controversial. Previous studies have only used plain films. In order to study remodelling, a retrospective study of 53 patients using high-definition CT was performed. There was no evidence of remodelling or resorption of osteophytes and persistent osteophytes continued to deform the spinal cord for up to 12 years after fusion. The importance of this in relation to cervical spinal surgery is that every effort should be made to remove posterior osteophytes during anterior interbody fusion. 相似文献
6.
The 16-kDa α-crystallin (Acr) protein of Mycobacterium tuberculosis is required for growth in macrophages 下载免费PDF全文
7.
8.
Free-feeding and free-drinking patterns of male rats following treatment with opiate kappa agonists.
Three experiments investigated the effects of PD117302 and U50,488H on the patterns of food and water intake by male rats. Experiment 1 demonstrated early dose-related suppression of food and water intake after PD117302 (0, 1.25, 2.5, 5 mg/kg). The initial suppression of drinking was followed by a sustained increase 4-12 h after drug administration. Experiment 2 demonstrated that 2.5 mg/kg PD117302 failed to increase food intake whether given at the beginning of the night (high baseline food intake) or the beginning of the day (low baseline food intake). Experiment 3 showed that 0.5 mg/kg U50,488H significantly enhanced meal size but, at doses of 0.5, 1.0, and 2.0 mg/kg, had no effect on overall food intake. U50,488H also produced delayed, dose-related increases in water intake. The results suggest kappa receptors may have limited importance in modulating ad lib food intake and demonstrate the behavioural characteristics of increased drinking after excessive urine output. 相似文献
9.
Rachel K. Clifton Barbara A. Morrongiello John M. Dowd 《Developmental psychobiology》1984,17(5):519-536
Infants aged 2 and 6 months were tested with the precedence effect, an auditory phenomenon involving sound localization. Each infant was tested with two types of stimuli: sound from a single loudspeaker and precedence-effect sounds produced by the same sound put through two loudspeakers, with one output leading the other by 7 msec. Older infants localized precedence-effect stimuli as they did single-source stimuli, indicating that they perceived this phenomenon as expected. Two-month-olds turned their heads toward single-source sounds, but did not localize precedence-effect sounds, suggesting that that more difficult perceptual task had not been achieved at this age. In general, headturning toward sound proved far more difficult to elicit in younger infants. A click train was ineffective, but a tape-recorded human voice elicited above-chance low-level turning. The developmental changes in auditory behavior are discussed in terms of the rapid growth of the auditory cortex. 相似文献
10.