全文获取类型
收费全文 | 256篇 |
免费 | 13篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 7篇 |
妇产科学 | 1篇 |
基础医学 | 21篇 |
口腔科学 | 10篇 |
临床医学 | 11篇 |
内科学 | 31篇 |
皮肤病学 | 1篇 |
神经病学 | 69篇 |
特种医学 | 27篇 |
外科学 | 23篇 |
综合类 | 16篇 |
一般理论 | 2篇 |
预防医学 | 6篇 |
眼科学 | 5篇 |
药学 | 15篇 |
肿瘤学 | 24篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 7篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 16篇 |
2012年 | 17篇 |
2011年 | 30篇 |
2010年 | 18篇 |
2009年 | 16篇 |
2008年 | 25篇 |
2007年 | 26篇 |
2006年 | 16篇 |
2005年 | 9篇 |
2004年 | 6篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1997年 | 1篇 |
1995年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1975年 | 1篇 |
1971年 | 1篇 |
1969年 | 2篇 |
1968年 | 4篇 |
1967年 | 1篇 |
排序方式: 共有270条查询结果,搜索用时 0 毫秒
1.
2.
Chandrika Veerareddy MDS K. Chandrasekharan Nair MDS G. Ramaswamy Reddy MDS 《Journal of prosthodontics》2012,21(7):561-568
Loss of orbital content can cause functional impairment, disfigurement of the face, and psychological distress. Rehabilitation of an orbital defect is a complex task, and if reconstruction by plastic surgery is not possible or not desired by the patient, the defect can be rehabilitated by an orbital prosthesis. The prosthetic rehabilitation in such cases depends on the precisely retained, user‐friendly removable maxillofacial prosthesis. Many times, making an impression of the orbital area with an accurate record of surface details can be a difficult procedure. The critical areas are making a facial moulage, mold preparation, and attaching the retention device, particularly when eyeglass frames are used. This case focuses on these hindrance factors. A simple basket was used for the impression tray to obtain the facial moulage. A putty mold was used, and attachment of the prosthesis to a retention device was accomplished with positional distance. This method proves to be an economical and simple way of making an orbital prosthesis. 相似文献
3.
Divyata R. Hingwala Chandrasekharan Kesavadas Bejoy Thomas Tirur R. Kapilamoorthy P. Sankara Sarma 《Annals of Indian Academy of Neurology》2013,16(2):229-233
Background:
The purpose of this study was to evaluate the difference in the occurrence of the various “traditional” imaging signs of intracranial hypertension (IIH) on magnetic resonance imaging (MRI) in patients with idiopathic (IIH) and secondary intracranial hypertension.Materials and Methods:
In a retrospective analysis, the MRI findings of 21 patients with IIH and 60 patients with secondary intracranial hypertension (41 with tumors; 19 with intracranial venous hypertension) were evaluated for the presence or absence of various “traditional” imaging signs of IIH (perioptic nerve sheath distention, vertical buckling of optic nerve, globe flattening, optic nerve head protrusion and empty sella) using the Fisher’s exact test. Odds ratios were also calculated. Statistical Package for the Social Sciences version 17.0 was used for statistical analysis. Subgroup analysis of the IIH versus tumors and IIH versus venous hypertension were performed.Results:
Optic nerve head protrusion and globe flattening were significantly associated with IIH. There was no statistically significant difference in the occurrence of rest of the findings. On subgroup analysis, globe flattening and optic nerve head protrusion occurred significantly more often in IIH than in tumors. However, there was no statistically significant difference in the occurrence of any of these findings in patients with IIH and venous hypertension.Conclusions:
IIH is a diagnosis of exclusion. While secondary causes of raised intracranial pressure (ICP) have obvious clinical findings on MRI, some conditions like cerebral venous thrombosis may have subtle signs and differentiating between primary and secondary causes may be difficult. In the absence of any evident cause of raised ICP, presence of optic nerve head protrusion or globe flattening can suggest the diagnosis of IIH. 相似文献4.
We report three cases of Vitamin B12 deficiency with symmetrical posterior spinal cord lesions and discuss the differential diagnosis, some of which are not well known. Because the degree of resolution of the clinical symptoms in subacute combined degeneration depends on early detection, MRI findings should not be missed. 相似文献
5.
Swathi Vanaja Chandrasekharan Nithiyanandan Krishnan Siriki Atchimnaidu Gowtham Raj Anusree Krishna P. K. Soumya Sagar Suresh Das Reji Varghese 《RSC advances》2021,11(32):19856
Two-component organogels offer several advantages over one-component gels, but their design is highly challenging. Hence, it is extremely important to design new approaches for the crafting of two-component organogels with interesting optical and mechanical properties. Herein, we report the design of a new class of two-component supergelators obtained from the assembly between acid functionalized tetraphenylethylene (TPE)-based dendrons and alkylated melamine. No gelation behaviour is observed for the individual components, but interestingly, remarkable gelation behaviour is observed for their hydrogen-bonded complex. The primary driving force responsible for the gelation is the strong π–π stacking interaction of TPE units. Because of the strong π-stacking of TPEs in the gel state, the C(sp2)–C(sp2) bond rotation of the TPE segment is completely arrested in the gel state, which results in intense fluorescence emission of the gels. Furthermore, excellent elastic response is observed for the gels as evident from their high storage modulus compared to loss modulus values. Our results clearly demonstrate that by the appropriate selection of the molecular components, this approach can be applied for the creation of functional nanomaterials with emergent properties absent in the individual blocks.Design of a novel class of two-component, highly emissive, low molecular weight supergelator is reported. 相似文献
6.
Savith Kumar Chinmay P. Nagesh Bejoy Thomas Ashalatha Radhakrishnan Ramshekhar N. Menon Chandrasekharan Kesavadas 《Journal of neuroradiology. Journal de neuroradiologie》2018,45(1):6-14
Background and purpose
The study evaluated the utility of arterial spin labeling (ASL) perfusion imaging in Rasmussen's encephalitis (RE).Material and methods
The hospital electronic database was searched using the search words “encephalitis,” “autoimmune encephalitis” and “Rasmussen's encephalitis” for the period of 1 Jan 2015 to 31 Jan 2017. Clinically diagnosed cases of RE for which epilepsy protocol magnetic resonance imaging (MRI) with perfusion imaging (ASL) performed on a 3T scanner were retrieved. The diagnosis of RE was based on Bien's criteria (Bien et al., 2005). We obtained patient's demographic details, clinical features, electrophysiological studies, and follow-up data from electronic hospital records.Results
We included nine patients with RE of whom seven patients showed increased perfusion, and two patients decreased perfusion. Among these patients, MRI changes of gyral hyperintensity without volume loss corresponded to regional ASL hyperperfusion in six patients and ASL hypoperfusion in one patient. Two patients who showed ASL hypoperfusion had corresponding atrophy on MRI. Eight patients of RE had epilepsia partialis continua (EPC) or daily seizures, and one patient was seizure-free post-surgery. Five patients showed a concordance of ASL hyperperfusion with clinical ictal onset zone. Among the seven patients with ASL hyperperfusion, the finding was concordant (complete or partial) with the electroencephalogram (EEG) ictal onset zone in six patients and with interictal epileptiform discharges (IED) in seven patients.Conclusion
Increased perfusion in ASL of the involved brain parenchyma in RE is a common MRI finding and may be due to either active inflammation of the brain involved or a seizure-related finding. 相似文献7.
8.
Advanced MR imaging in Lhermitte-Duclos disease: moving closer to pathology and pathophysiology 总被引:3,自引:0,他引:3
Introduction Lhermitte-Duclos disease (LDD, dysplastic gangliocytoma) is an extremely rare cerebellar lesion of uncertain etiology. The
debate as to whether it constitutes a neoplastic, malformative, or hamartomatous lesion is still continuing. In this report
we explore the usefulness of susceptibility-weighted imaging (SWI), diffusion weighted imaging (DWI), perfusion imaging, and
chemical shift imaging (CSI) in demonstrating the pathology and pathophysiology in two patients with LDD.
Methods MR imaging of the brain and the cervicodorsal spine was performed on a 1.5-T scanner in a 47-year-old woman presenting with
numbness and paresthesia of both upper and lower limbs, and in a 17-year-old male with right frontal headache associated with
neck pain.
Results Routine imaging in the first patient showed a left-side cerebellar mass with characteristic ’tiger-striped’ thick folia associated
with Chiari I malformation, tonsillar herniation and cervicodorsal syringomyelia and in the second patient a right cerebellar
mass with similar findings. The SWI demonstrated the characteristic deep running veins between the folia, which is thought
to be the cause for vascular contrast enhancement. Diffusion showed a T2 shine-through effect with mild increased diffusivity,
and perfusion showed increase in relative cerebral blood volume, relative cerebral blood flow, and mean transit time in the
lesion. MR spectroscopy demonstrated reduction in metabolites and a prominent lactate peak in both the patients. The pathological
and pathophysiological significance of these findings is discussed.
Conclusion MRI with the newer imaging capabilities can demonstrate the pathology and pathophysiology in Lhermitte-Duclos disease better.
SWI helps in detecting the veins around the thickened folia. 相似文献
9.
Augmented‐reality‐based skills training for robot‐assisted urethrovesical anastomosis: a multi‐institutional randomised controlled trial 下载免费PDF全文
10.
Milan Jolapara Satya Narayan Patro Chandrasekharan Kesavadas Jitender Saini Bejoy Thomas Arun Kumar Gupta Narendra Bodhey Vishnupuri Venkatraman Radhakrishnan 《Neuroradiology》2011,53(1):63-68