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81.
NMR imaging in the recognition of giant intracranial aneurysms 总被引:2,自引:0,他引:2
B S Worthington D M Kean R C Hawkes G N Holland W S Moore R Corston 《AJNR. American journal of neuroradiology》1983,4(3):835-836
Most giant aneurysms present clinically as intracranial mass lesions. Many contain an organized lamellated thrombus with only a small eccentric lumen remaining that can be opacified at angiography. Four patients with such aneurysms were studied using flow-dependent nuclear magnetic resonance scanning sequences. The aneurysms show a smooth rounded margin, and the thrombus within is clearly distinguishable from the blood flowing through the patent lumen, which gives a low signal. By using different scan sequences it is possible to prove that the area of low signal is indeed fluid in rapid motion, thus confirming the diagnosis. 相似文献
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Cengiz??zcanEmail author Handan?Zeren Derya?ümit?Talas Melek?Kü?üko?lu Kemal?G?rür 《European archives of oto-rhino-laryngology》2005,262(1):55-60
Antrochoanal polyp (ACP) is a soft tissue mass originating from the maxillary antrum, emerging from the ostium and extending to the choana through the nasal cavity. Our aim was to investigate the light microscopic and ultrastructural features of ACP and to compare these with nasal polyps originating from the middle meatus (MMP). Seven ACP and seven MMP specimens were evaluated by transmission electron microscopy (TEM) and light microscopy. TEM examination showed epithelial cells with intact cilia covering both polyps. In some MMP cases, degeneration of the epithelium associated with some cilia loss was noted. Goblet cell hyperplasia was more prominent in MMP cases. Degeneration and partial destruction of the endothelial cells of the blood vessels were common findings in ACP cases; however, in the MMP group, endothelial cells were mostly intact with a few aggregates of ribosomes, and intact cell junctions were noted. Light microscopic examination revealed that inflammatory cells in the ACP group were numerous. However, eosinophils were predominant in MMP cases. Squamous metaplasia of the surface epithelium was detected in five ACP cases, but in none of the MMP cases. Basement membrane thickening was detected in two cases of the ACP and in four cases of the MMP group. There was a statistically significant difference between the two groups for inflammatory cells, eosinophilic cell infiltration, squamous cell metaplasia, endothelial cell destruction and goblet cell metaplasia. In conclusion, the low number of eosinophils, the high number of other inflammatory cells, the normal appearing basement membrane and intact and normal surface epithelium may reveal that the etiology of ACP might arise from chronic inflammatory processes rather than allergy. The destruction of the endothelium may be considered as a further sign of chronic inflammation. 相似文献
84.
Payton A Gibbons L Davidson Y Ollier W Rabbitt P Worthington J Pickles A Pendleton N Horan M 《Molecular psychiatry》2005,10(12):1133-1139
Dysfunction of the serotonergic pathway disrupts normal cognitive functioning and is believed to be the underlying basis for a variety of psychiatric disorders. Two functional polymorphisms within the serotonin transporter (SLC6A4) gene (promoter 44 bp insertion/deletion (HTTLPR) and an intron two 16 or 17 bp variable number tandem repeat (VNTR2)) have been extensively studied in psychiatric conditions but not in the cognitive functioning of normal individuals. We have investigated these two polymorphisms for association with both the level of cognitive abilities and their decline with age using a cohort consisting of over 750 elderly nondemented individuals with a follow-up of up to 15 years. We found that volunteers homozygous for the VNTR2 12 allele had a faster rate of decline for all cognitive tests. This reached significance for both tests of fluid intelligence (novel problem solving) (AH1 P=0.002, AH2 P=0.014), the test of semantic memory (P=0.010) and general cognitive ability (P=0.006). No association was observed between the HTTLPR polymorphism and the rate of cognitive decline when analysed either independently or in combination with the VNTR2 polymorphism based on their influence on expression in vitro. No associations were observed between the two polymorphisms and the baseline level of cognitive abilities. This is only the second gene that has been reported to regulate the rate of cognitive decline in nondemented individuals and may be a target for the treatment of cognitive impairment in the elderly. 相似文献
85.
Worthington J 《Rheumatology (Oxford, England)》2005,44(Z4):iv5-iv8
The contribution of the arc Epidemiology Unit over its 50-yr history to the study of the genetic epidemiology of rheumatoid arthritis (RA) has been reviewed. Early family and population based studies carried out by John Lawrence were important in establishing the role of both genetic and environmental factors in determining susceptibility to RA. More recently, under the leadership of Alan Silman, population-based cohorts, twin- and family-based studies have formed the basis for an extensive programme of research aimed at identifying specific genetic factors that might influence susceptibility and outcome. A review of linkage and association studies is presented. 相似文献
86.
AIM: To evaluate the effect of abdominal aortic aneurysm wall calcification on subsequent sac shrinkage after endovascular repair. MATERIALS AND METHODS: Seventy-three patients underwent endovascular aneurysm repair. The degree of sac wall calcification on pre-procedural computed tomography (CT) examination was graded from 1 to 4 according to the degree of circumferential involvement. On follow-up CT imaging, the maximum transverse diameter (MTD) of the sac was recorded, as well as the presence or absence of endoleak. In those patients with a non-shrinking aneurysm, but no CT evidence of endoleak, contrast-enhanced ultrasound (USS) was performed. Any patient with an endoleak, however diagnosed, was excluded from the study. Kruskal-Wallis and Spearman's rank correlation coefficient testing was applied to compare the degree of calcification and change in MTD. RESULTS: Sixty-three pre-procedural CT images were available for calcification grading. Six of this group had endoleaks resulting in 57 sets of data being available for the study. A reduction in MTD occurred in 68.25% of these patients by 1 year post-procedure. Our figures show aortic calcification is inversely associated with MTD reduction at 6 months (p = 0.01), 1 year (p = 0.05) and 2 years (p = 0.05). CONCLUSION: This study indicates that the degree of aortic wall calcification is significant in predicting MTD reduction post-endovascular repair. The possible mechanisms and implications of this are discussed. 相似文献
87.
Macfarlane TV Blinkhorn AS Davies RM Kincey J Worthington HV 《Journal of dental research》2004,83(9):712-717
Orofacial pain is often persistent, but it is not clear why it lasts in some patients but not in others. We aimed to describe the natural course of orofacial pain in a general population sample over a four-year period and to identify factors that would predict the persistence of pain. A cross-sectional population-based survey was conducted in the United Kingdom, involving 2504 participants (participation rate 74%), of whom 646 (26%) reported orofacial pain. Overall, 424 (79% adjusted participation rate) of these individuals participated at the four-year follow-up, of whom 229 (54%) reported orofacial pain and 195 (46%) did not report such pain. Persistent orofacial pain was associated with females, older age, psychological distress, widespread body pain, and taking medication for orofacial pain at baseline. These findings may have implications for the identification and treatment of patients with orofacial pain. 相似文献
88.
Patients' beliefs about illness are important because they influence adherence and adjustment, but they are often surprising and idiosyncratic. Qualitative research can identify them in ways that are not shaped by psychological theory, but quantification is necessary if clinicians are to be informed about the beliefs that are likely to be prevalent in their patients. Qualitative analysis of interviews with 16 haemodialysis (HD) patients identified beliefs about end-stage renal failure (ESRF) and its treatment that were formed into a questionnaire, completed by 156 similar patients. Patients attributed ESRF to diverse factors including lack of self-care and inadequate medical care. Patients lacked a clear belief in the mechanism of action of dietary control, and its necessity was not readily acknowledged. The common view of haemodialysis as 'cleansing' extended to the reassuring belief that it would purge the body of disallowed food or drink. Many patients regarded haemodialysis and dietary control as externally imposed challenges that dominated life. The findings identify potential targets for educational intervention to improve adherence and adjustment and predictions about effects of patients' beliefs that can be tested in future prospective studies. 相似文献
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