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排序方式: 共有2109条查询结果,搜索用时 15 毫秒
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Leonardo Bonilha MD PhD Paulien M. de Vries Diana J. Vincent MD PhD Chris Rorden MD PhD Paul S. Morgan Mark W. Hurd PhD Nada Besenski MD Kenneth J. Bergmann MD Vanessa K. Hinson MD PhD 《Movement disorders》2007,22(8):1110-1116
We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1‐negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society 相似文献
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Evaluation of a new magnetic resonance imaging method for quantitating adipose tissue areas 总被引:3,自引:0,他引:3
W Sobol S Rossner B Hinson E Hiltbrandt N Karstaedt P Santago N Wolfman A Hagaman J R Crouse 《International journal of obesity (2005)》1991,15(9):589-599
We have developed a new magnetic resonance imaging (MRI) protocol to quantitate intraabdominal and subcutaneous fat and have validated it by comparing measurements of fat areas by MRI with those obtained by computed tomography (CT) in 11 asymptomatic volunteers who all had a single CT and MRI image taken at the level of the umbilicus. The new MRI protocol was based on a water-fat separation method by which the slice selection routines excite water and fat protons in different positions along the slice select direction. This method performed more reliably than earlier methods based on phase differences between water and fat signals. Fat areas measured by MRI exceeded those measured by CT by 8-22 percent, and fat areas and ratios obtained by MRI correlated well with CT (r = 0.98 for areas and, for ratios, r = 0.81). The ratio of intraabdominal/subcutaneous fat measured by MRI in seven males was significantly greater than that in four females. We also compared the new method with a previously published inversion recovery (IR) method in seven additional volunteers. Agreement between the two methods was excellent, and the major differences were technical: the IR protocol produced images that may require custom image processing programs when obtained on some scanners. Comparability of the two methods provides further reassurance of the validity of both. MRI presents an attractive opportunity for directly measuring intraabdominal fat in order to correlate this with metabolic parameters and to visualize changes during weight loss. 相似文献
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This study investigated whether in vitro immunotherapy with rIL-2 which augments human natural cytotoxicity and generation of lymphokine-activated killer cells diminished or inhibits the severity of therapeutically induced human in vitro NK immunosuppression. We demonstrate that rIL-2 induces a rapid and potent enhancement of cytolytic killing and that pretreatment of effector cells for one hour with rIL-2 yields effector cells which are more resistant to drug-induced immunosuppression. Additionally, we demonstrate cells pretreated for 24 hours with rIL-2 were less sensitive to drug inhibitory effects than rIL-2 non-treated or one hour pretreated effector cells. Our data suggest prophylactic treatment with IL-2 for drug induced immunosuppression is feasible. 相似文献
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Strut fixation of an extensive flail chest 总被引:2,自引:0,他引:2
R J Landreneau J M Hinson S R Hazelrigg J A Johnson T M Boley J J Curtis 《The Annals of thoracic surgery》1991,51(3):473-475
The indications for and preferred approaches to operative stabilization of posttraumatic chest wall instability are uncertain. We suggest this simple, rapid, and effective approach to surgical stabilization by Luque rod strutting of the flail segment when operation is required. 相似文献
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Definitive radiation therapy for selected cancers of the rectum 总被引:5,自引:0,他引:5
During the last 15 years, over 400 patients with adenocarcinoma of the rectum have undergone a course of endocavitary irradiation for cure or palliation of Dukes' A and B disease. This treatment method makes use of an unconventional fractionation scheme, by which the tumour receives 10,000-12,000 cGy in approximately four fractions over a period of about 60 days. The treatments are separated by an interval of 2 or 3 weeks. This method of definitive irradiation allows suitable patients to avoid abdominoperineal resection and its drawbacks. Hospitalization is avoided and the patients maintain a normal daily life. Approximately 15-20 per cent of all rectal cancer patients may be expected to fulfil the criteria for selection, which are sufficiently strict that the local control (95 per cent) and 5-year survival rates (94 per cent) can exceed those of surgery for comparable disease. 相似文献
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We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed. 相似文献