全文获取类型
收费全文 | 1772篇 |
免费 | 70篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 75篇 |
儿科学 | 72篇 |
妇产科学 | 84篇 |
基础医学 | 192篇 |
口腔科学 | 18篇 |
临床医学 | 106篇 |
内科学 | 434篇 |
皮肤病学 | 17篇 |
神经病学 | 237篇 |
特种医学 | 56篇 |
外科学 | 209篇 |
综合类 | 5篇 |
一般理论 | 2篇 |
预防医学 | 80篇 |
眼科学 | 24篇 |
药学 | 119篇 |
肿瘤学 | 120篇 |
出版年
2023年 | 12篇 |
2022年 | 23篇 |
2021年 | 44篇 |
2020年 | 23篇 |
2019年 | 40篇 |
2018年 | 37篇 |
2017年 | 21篇 |
2016年 | 24篇 |
2015年 | 33篇 |
2014年 | 51篇 |
2013年 | 72篇 |
2012年 | 106篇 |
2011年 | 143篇 |
2010年 | 68篇 |
2009年 | 52篇 |
2008年 | 107篇 |
2007年 | 148篇 |
2006年 | 123篇 |
2005年 | 104篇 |
2004年 | 150篇 |
2003年 | 104篇 |
2002年 | 95篇 |
2001年 | 6篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 14篇 |
1997年 | 5篇 |
1996年 | 13篇 |
1995年 | 5篇 |
1994年 | 8篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 10篇 |
1990年 | 14篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1984年 | 5篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1976年 | 6篇 |
1974年 | 6篇 |
1973年 | 8篇 |
1963年 | 4篇 |
1960年 | 4篇 |
1948年 | 4篇 |
1931年 | 5篇 |
1930年 | 6篇 |
1912年 | 3篇 |
排序方式: 共有1850条查询结果,搜索用时 125 毫秒
41.
Ricardo Petraco Rasha Al-Lamee Matthias Gotberg Andrew Sharp Farrel Hellig Sukhjinder S. Nijjer Mauro Echavarria-Pinto Tim P. van de Hoef Sayan Sen Nobuhiro Tanaka Eric Van Belle Waldemar Bojara Kunihiro Sakoda Martin Mates Ciro Indolfi Salvatore De Rosa Christian J. Vrints Steven Haine Hiroyoshi Yokoi Flavio L. Ribichini Martjin Meuwissen Hitoshi Matsuo Luc Janssens Ueno Katsumi Carlo Di Mario Javier Escaned Jan Piek Justin E. Davies 《American heart journal》2014
42.
43.
Brehm MA Racki WJ Leif J Burzenski L Hosur V Wetmore A Gott B Herlihy M Ignotz R Dunn R Shultz LD Greiner DL 《Blood》2012,119(12):2778-2788
Immunodeficient mice engrafted with human HSCs support multidisciplinary translational experimentation, including the study of human hematopoiesis. Heightened levels of human HSC engraftment are observed in immunodeficient mice expressing mutations in the IL2-receptor common γ chain (IL2rg) gene, including NOD-scid IL2rγ(null) (NSG) mice. Engraftment of human HSC requires preconditioning of immunodeficient recipients, usually with irradiation. Such preconditioning increases the expression of stem cell factor (SCF), which is critical for HSC engraftment, proliferation, and survival. We hypothesized that transgenic expression of human membrane-bound stem cell factor Tg(hu-mSCF)] would increase levels of human HSC engraftment in nonirradiated NSG mice and eliminate complications associated with irradiation. Surprisingly, detectable levels of human CD45(+) cell chimerism were observed after transplantation of cord blood-derived human HSCs into nonirradiated adult as well as newborn NSG mice. However, transgenic expression of human mSCF enabled heightened levels of human hematopoietic cell chimerism in the absence of irradiation. Moreover, nonirradiated NSG-Tg(hu-mSCF) mice engrafted as newborns with human HSCs rejected human skin grafts from a histoincompatible donor, indicating the development of a functional human immune system. These data provide a new immunodeficient mouse model that does not require irradiation preconditioning for human HSC engraftment and immune system development. 相似文献
44.
Orlin Belyaev MD Sonja RosenkranzJohanna Munding MD Torsten Herzog Ansgar M. Chromik Andrea Tannapfel Waldemar Uhl 《The Journal of surgical research》2013
Background
Hard pancreas is welcome by surgeons performing resective pancreatic surgery, because it is believed to offer better suture holding capacity (SHC), thus decreasing the risk for a postoperative leak. However, neither the actual SHC of pancreatic tissue in humans nor its determinants have been studied.Methods
We directly measured SHC for polydioxanone 5–0 suture and tissue hardness at the pancreatic isthmus in 53 human pancreata using a dynamometer and a durometer. A histologic score based on fibrosis grade, fat content, pancreatic duct size, and signs of chronic pancreatitis was calculated for every sample. We tested the hypothesis that SHC of the pancreas was proportional to tissue hardness, and evaluated the role of different possible histomorphologic determinants of SHC.Results
Suture-holding capacity correlated perfectly with tissue hardness (r = 0.98; P < 0.001; 95% confidence interval, 0.96–0.99). The histologic score showed a stronger correlation with both parameters than any single histologic parameter. The SHC of transductal sutures was significantly higher than that of pure transparenchymal sutures. The SHC and hardness were significantly lower in patients who developed a clinically relevant pancreatic fistula postoperatively.Conclusions
A mixture of histomorphologic features of human pancreas determines its tissue hardness and SHC. Involvement of the main pancreatic duct in the suture line appears to increase the mechanical strength of the pancreatic anastomosis. 相似文献45.
46.
47.
48.
49.
Luszczki JJ Swiader MJ Swiader K Paruszewski R Turski WA Czuczwar SJ 《Neuroscience letters》2007,421(1):87-90
This study focused on the evaluation of anticonvulsant properties of isonicotinic acid benzylamide (iso-Nic-BZA) in numerous experimental seizure models (maximal electroshock [MES]-, bicuculline [BIC]-, pentylenetetrazole [PTZ]-, pilocarpine [PILO]-, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid [AMPA]-, kainic acid [KA]- and N-methyl-d-aspartic acid [NMDA]-induced seizures). Moreover, acute adverse-effect profile of the agent with respect to impairment of motor coordination was assessed in animals subjected to the chimney test. The evaluation of time-course and dose-response relationships for iso-Nic-BZA provided evidence that the compound produced the peak to maximum antielectroshock action and acute adverse effects at 5min after its systemic (i.p.) administration. Iso-Nic-BZA exerted a clear-cut anticonvulsant action against maximal electroshock-induced seizures in mice and its ED(50) value was 70.6 (56.4-88.4)mg/kg. The assessment of acute adverse effects in the chimney test revealed that the agent produced acute neurotoxic effects and its TD(50) value was 135.6 (108.8-169.0)mg/kg. Additionally, iso-Nic-BZA showed the anticonvulsant activity in numerous chemically-induced seizures (AMPA-, BIC-, KA-, and PTZ-evoked clonic convulsions), remaining virtually ineffective (at doses up to 200mg/kg) in PILO- and NMDA-induced seizures in mice. Based on this study, one can conclude that iso-Nic-BZA due to the short time to peak of its maximum anticonvulsant effects (5min after its i.p. administration), deserves more attention as a potential antiepileptic drug for patients in status epilepticus. 相似文献
50.
Ryberg C Rostrup E Stegmann MB Barkhof F Scheltens P van Straaten EC Fazekas F Schmidt R Ferro JM Baezner H Erkinjuntti T Jokinen H Wahlund LO O'brien J Basile AM Pantoni L Inzitari D Waldemar G;LADIS study group 《Neurobiology of aging》2007,28(6):955-963
Corpus callosum (CC) is the main tract connecting the hemispheres, but the clinical significance of CC atrophy is poorly understood. The aim of this work was to investigate clinical and functional correlates of CC atrophy in subjects with age-related white matter changes (ARWMC). In 569 elderly subjects with ARWMC from the Leukoaraiosis And DISability (LADIS) study, the CC was segmented on the normalised mid-sagittal magnetic resonance imaging (MRI) slice and subdivided into five regions. Correlations between the CC areas and subjective memory complaints, mini mental state examination (MMSE) score, history of depression, geriatric depression scale (GDS) score, subjective gait difficulty, history of falls, walking speed, and total score on the short physical performance battery (SPPB) were analyzed. Significant correlations between CC atrophy and MMSE, SPPB, and walking speed were identified, and the CC areas were smaller in subjects with subjective gait difficulty. The correlations remained significant after correction for ARWMC grade. In conclusion, CC atrophy was independently associated with impaired global cognitive and motor function in subjects with ARWMC. 相似文献