全文获取类型
收费全文 | 1022篇 |
免费 | 49篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 45篇 |
妇产科学 | 75篇 |
基础医学 | 99篇 |
口腔科学 | 47篇 |
临床医学 | 91篇 |
内科学 | 226篇 |
皮肤病学 | 20篇 |
神经病学 | 70篇 |
特种医学 | 25篇 |
外科学 | 210篇 |
综合类 | 14篇 |
一般理论 | 1篇 |
预防医学 | 18篇 |
眼科学 | 33篇 |
药学 | 28篇 |
中国医学 | 1篇 |
肿瘤学 | 49篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 14篇 |
2021年 | 26篇 |
2020年 | 23篇 |
2019年 | 22篇 |
2018年 | 26篇 |
2017年 | 21篇 |
2016年 | 39篇 |
2015年 | 53篇 |
2014年 | 55篇 |
2013年 | 57篇 |
2012年 | 83篇 |
2011年 | 67篇 |
2010年 | 46篇 |
2009年 | 53篇 |
2008年 | 60篇 |
2007年 | 89篇 |
2006年 | 75篇 |
2005年 | 69篇 |
2004年 | 61篇 |
2003年 | 50篇 |
2002年 | 33篇 |
2001年 | 8篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 3篇 |
1989年 | 8篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1982年 | 1篇 |
1964年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有1075条查询结果,搜索用时 281 毫秒
1.
Evaluation of Adult versus Pediatric Transesophageal Echocardiography Probe Efficiency for Guiding Septal Puncture during Atrial Fibrillation Ablation
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
2.
3.
Baki Hazer Alipaa Ayas Necati Beirli Necdet Saltek Bahattin M. Baysal 《Macromolecular chemistry and physics.》1989,190(8):1987-1996
Some new macroinitiators ( 5 ) containing azo and peroxy groups were synthesized by transformation of esters of poly(ethylene glycol) ( 1 ) (PEG) of different molecular weight with hydroxyl end groups and an azo group in the middle into the corresponding polymers with tert-butylperoxycarbonyl end groups by reaction with terephthaloyl chloride and subsequently with tert-butyl hydroporoxide. Decomposition in the presence of styrene at 60°C or with 3,6,9-triazaun-decane-1,11-diamine in presence of methyl methacrylate gave the corresponding ABA block copolymer 6 and the ABBA block copolymer 7 , respectively. Both block copolymers were used as polymeric initiators. The ABCBA block copolymer 8 was synthesized from 6 and methyl methacrylate or from 7 and styrene by thermally induced polymerization at 80°C. The resulting block copolymers were separated from the homopolymers by selective solvent extraction and characterized by spectroscopic and fractional precipitation methods. 相似文献
4.
The use of neuronal nuclear antigen (NeuN) as a reliable neuronal marker in the differential diagnosis of clear cell neoplasms of the central nervous system was determined in a biopsy series of 23 cases. Immunohistochemical analyses were carried out by antisera against neuronal nuclear antigen, synaptophysin, neuron-specific enolase, microtubule-associated protein 2, and glial fibrillary acidic protein. All eight central neurocytomas were characteristically immunolabeled by NeuN. NeuN immunoreactivity was uniformly strong and basically located in the nuclei of neurocytes. Despite this uniform staining pattern of central neurocytomas, 12 cases of oligodendrogliomas and three cases of ependymoma were negative for NeuN. As the diagnostic criteria for central neurocytoma include immunohistochemical and/or ultrastructural evidence for neuronal differentiation, NeuN as a sensitive and specific neuronal marker in formalin-fixed, paraffin-embedded tissues may greatly facilitate the differential diagnosis of central neurocytomas. 相似文献
5.
Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>
Abdulkadir Bayir A. Necdet Sirkecioğlu Harun Polat N. Mevlüt Aras 《Comparative clinical pathology》2007,16(2):119-126
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in
winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate
dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz,
which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively
affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters
are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal
changes of blood biochemistry in fish. 相似文献
6.
Lucas R Tacchini-Cottier F Guler R Vesin D Jemelin S Olleros ML Marchal G Browning JL Vassalli P Garcia I 《European journal of immunology》1999,29(12):4002-4010
To investigate the role of membrane lymphotoxin (LT)alpha1 / beta2 and its LTbeta receptor (LTbetaR) in the protective immune response to Mycobacterium bovis bacillus Calmette-Guérin (BCG) infection, we have used a soluble fusion molecule (LTbetaR-IgG1). LTbetaR-Ig treatment interferes with granuloma formation mainly in the spleen by inhibiting macrophage activation and nitric oxide synthase activity. In addition, a large accumulation of eosinophils was observed in the spleen of LTbetaR-Ig-treated infected mice. Decreased blood levels of IFN-gamma and increased IL-4 were also observed, suggesting that the LTbetaR pathway is important in BCG infection to favor a Th1 type of immune response. The treatment of transgenic mice expressing high blood levels of a soluble TNFR1-IgG3 fusion protein with LTbetaR-Ig resulted in a still higher sensitivity to BCG infection, and extensive necrosis in the spleen. In conclusion, these results suggest that the LTbetaR and the TNFR pathways are not redundant in the course of BCG infection and protective granuloma formation: the LTbetaR pathway appears to be important in spleen granuloma formation, whereas the TNFR pathway has a predominant role in other tissues. 相似文献
7.
Andrew Kochan Shaun Ong Sabina Guler Kerri A Johannson Christopher J Ryerson Gillian C Goobie 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundPatients use Facebook as a resource for medical information. We analyzed posts on idiopathic pulmonary fibrosis (IPF)-related Facebook groups and pages for the presence of guideline content, user engagement, and usefulness.ObjectiveThe objective of this study was to describe and analyze posts from Facebook groups and pages that primarily focus on IPF-related content.MethodsCross-sectional analysis was performed on a single date, identifying Facebook groups and pages resulting from separately searching “IPF” and “idiopathic pulmonary fibrosis.” For inclusion, groups and pages needed to meet either search term and be in English, publicly available, and relevant to IPF. Every 10th post was assessed for general characteristics, source, focus, and user engagement metrics. Posts were analyzed for presence of IPF guideline content, useful scientific information (eg, scientific publications), useful support information (eg, information about support groups), and potentially harmful information.ResultsEligibility criteria were met by 12 groups and 27 pages, leading to analysis of 523 posts. Of these, 42% contained guideline content, 24% provided useful support, 20% provided useful scientific information, and 5% contained potentially harmful information. The most common post source was nonmedical users (85%). Posts most frequently focused on IPF-related news (29%). Posts containing any guideline content had fewer likes or comments and a higher likelihood of containing potentially harmful content. Posts containing useful supportive information had more likes, shares, and comments.ConclusionsFacebook contains useful information about IPF, but posts with misinformation and less guideline content have higher user engagement, making them more visible. Identifying ways to help patients with IPF discriminate between useful and harmful information on Facebook and other social media platforms is an important task for health care professionals. 相似文献
8.
Murat Yilmaz Orhan Kalemci Hakan Yilmaz Necdet M. Palaz 《International journal of surgery case reports》2013,4(8):645-647
INTRODUCTIONSymtomatic lumbar ligamantum flavum calcification is quite rare in the young age group.PRESENTATION OF CASEThe authors report a case of young adult with diagnosis of lumbar spinal stenosis, presenting with leg pain and neurological deficits. Computerized tomography (CT) scan and magnetic resonance (MR) imaging studies revealed ossification of the ligamantum flavum as the causative factor of the disease and the patient recovered completely after the decompressive operation.DISCUSSIONIt is emphasized that attention should be given to this rare etiological factor of lumbar spinal stenosis.CONCLUSIONComplete relief can be achieved with early and adequate surgery. 相似文献
9.
Aylin Yaba Umit Kayisli Gamze Tanriover Necdet Demir 《International journal of developmental neuroscience》2011,29(2):131-136
Vasodilator-stimulated phosphoprotein (VASP) is a member of the Ena/VASP protein family and was for the first time identified in human platelets. VASP plays a role for cell adhesion and cell migration because of E/DFPPPPXD/E amino acid sequence in its structure which gives reaction with focal adhesion proteins. In this study we suggest that VASP expression may have important role for neural cell migration, differentiation, axonal growth and angiogenesis during prenatal cerebral cortical development. Our aim is to detect VASP expression by means of immunohistochemistry and Western blot analysis in developing human neocortex and adult brain cortex (n = 12 samples from first, second, and third trimesters and n = 3 adult normal cerebral cortex). Our results suggest that VASP showed different immunostaining patterns between cerebral cortical plates in prenatal and adult human brain samples. We observed that the expression patterns of the VASP protein are clearly identified in fibers, cytoplasm of neural cells and endothelial cells of vessels. We detected that VASP indicates progressive expression from the adult brain to second trimester neocortexes. Therefore, we suggest that VASP may play a crucial role in the regulation of human neonatal cerebral cortical development. 相似文献