全文获取类型
收费全文 | 635篇 |
免费 | 37篇 |
国内免费 | 5篇 |
专业分类
儿科学 | 36篇 |
妇产科学 | 20篇 |
基础医学 | 85篇 |
口腔科学 | 2篇 |
临床医学 | 73篇 |
内科学 | 164篇 |
皮肤病学 | 53篇 |
神经病学 | 39篇 |
特种医学 | 25篇 |
外科学 | 43篇 |
综合类 | 13篇 |
预防医学 | 64篇 |
眼科学 | 7篇 |
药学 | 40篇 |
肿瘤学 | 13篇 |
出版年
2021年 | 8篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 10篇 |
2017年 | 9篇 |
2016年 | 8篇 |
2015年 | 9篇 |
2014年 | 13篇 |
2013年 | 24篇 |
2012年 | 16篇 |
2011年 | 14篇 |
2010年 | 17篇 |
2009年 | 10篇 |
2008年 | 24篇 |
2007年 | 22篇 |
2006年 | 29篇 |
2005年 | 23篇 |
2004年 | 25篇 |
2003年 | 18篇 |
2002年 | 32篇 |
2001年 | 21篇 |
2000年 | 19篇 |
1999年 | 19篇 |
1998年 | 16篇 |
1997年 | 4篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 18篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 16篇 |
1989年 | 20篇 |
1988年 | 19篇 |
1987年 | 20篇 |
1986年 | 16篇 |
1985年 | 18篇 |
1984年 | 9篇 |
1983年 | 19篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 4篇 |
1975年 | 2篇 |
1974年 | 4篇 |
1961年 | 2篇 |
1956年 | 3篇 |
1838年 | 2篇 |
排序方式: 共有677条查询结果,搜索用时 312 毫秒
1.
2.
3.
4.
5.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
6.
7.
The neurotoxic actions of kainate were examined in incubated slices of adult and immature rat cerebellum using light- and electron-microscopy. In the adult, Purkinje cells and inhibitory interneurones became selectively necrotic at concentrations between 5 micro M and 20 micro M. At 30 micro M, granule cells also became affected. In the immature cerebellum, at an age (8 days after birth) when the parallel fibres (thought to use glutamate as transmitter) are largely yet to be developed, selective toxicity was still evident but Purkinje cells and inhibitory interneurones were about 10-fold, and granule cells about 30-fold, less sensitive to kainate than in the adult. Kainate and other excitotoxins also increased cyclic GMP levels in cerebellar slices, apparently through the activation of excitatory amino acid receptors. In the adult tissue, the dose-cyclic GMP response curve to kainate was biphasic suggesting the presence of two components. The lower concentrations of kainate eliciting the first component mirrored those inducing selective necrosis of Purkinje cells and inhibitory interneurones while the second component correlated with necrosis of granule cells. Similar correlations applied to the immature cerebellum, but here kainate neurotoxicity appeared to be associated with the activation of receptor types different from those evident in the adult. It is suggested that kainate receptors, whose activation is associated with both neurotoxic damage and elevation of cyclic GMP levels, are located on all cell types in the adult cerebellum, with Purkinje cells and inhibitory interneurones displaying a higher sensitivity to kainate than granule cells. The lower sensitivity of immature cerebellum to the neurotoxic effect of kainate is probably due to lower levels of kainate receptors. 相似文献
8.
C Camenzuli AN DiMarco KE Isaacs Y Grant J Jackson A Alsafi C Harvey TD Barwick N Tolley FF Palazzo 《Annals of the Royal College of Surgeons of England》2021,103(1):29
IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes. 相似文献
9.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
10.
A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed. 相似文献