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461.
Sander CJ Verfaillie Sandeep SV Golla Tessa Timmers Hayel Tuncel Chris WJ van der Weijden Patrick Schober Robert C Schuit Wiesje M van der Flier Albert D Windhorst Adriaan A Lammertsma Bart NM van Berckel Ronald Boellaard 《Journal of cerebral blood flow and metabolism》2021,41(3):569
Accumulation of amyloid beta (Aβ) is one of the pathological hallmarks of Alzheimer’s disease (AD), which can be visualized using [18F]florbetapir positron emission tomography (PET). The aim of this study was to evaluate various parametric methods and to assess their test-retest (TRT) reliability. Two 90 min dynamic [18F]florbetapir PET scans, including arterial sampling, were acquired (n = 8 AD patient, n = 8 controls). The following parametric methods were used; (reference:cerebellum); Logan and spectral analysis (SA), receptor parametric mapping (RPM), simplified reference tissue model2 (SRTM2), reference Logan (rLogan) and standardized uptake value ratios (SUVr(50–70)). BPND+1, DVR, VT and SUVr were compared with corresponding estimates (VT or DVR) from the plasma input reversible two tissue compartmental (2T4k_VB) model with corresponding TRT values for 90-scan duration. RPM (r2 = 0.92; slope = 0.91), Logan (r2 = 0.95; slope = 0.84) and rLogan (r2 = 0.94; slope = 0.88), and SRTM2 (r2 = 0.91; slope = 0.83), SA (r2 = 0.91; slope = 0.88), SUVr (r2 = 0.84; slope = 1.16) correlated well with their 2T4k_VB counterparts. RPM (controls: 1%, AD: 3%), rLogan (controls: 1%, AD: 3%) and SUVr(50–70) (controls: 3%, AD: 8%) showed an excellent TRT reliability. In conclusion, most parametric methods showed excellent performance for [18F]florbetapir, but RPM and rLogan seem the methods of choice, combining the highest accuracy and best TRT reliability. 相似文献
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Manabu Inoue Yasuhiro Kojima Akiyo Shinde Hitoshi Satoi Fumi Makino Masutarou Kanda Hiroshi Shibasaki 《Clinical neurology》2007,47(7):423-428
We presented a 43-year-old Japanese woman who acutely developed weakness of all extremities and difficulty in swallowing and drooping of eyelids, characterized by easy fatigability at the end of December, 2005. On general physical examination, she had moderate goiter. No cervical lymphadenopathy, cardiac murmur, or skin rash was noted. Neurologically, she had blepharoptosis, more on the right, only in the upright position with easy fatigability and marked weakness in the neck flexor, trunk, and all limb muscles much more proximally than distally. She had neither muscular atrophy nor upper motor neuron sign. Laboratory data showed slight leukocytosis with eosinophilia (up to 31%), and serum creatine kinase was markedly increased to over 2,000 IU/l. TSH receptor antibody (11.9%) and anti-acetylcholine receptor antibody (46.6 nmol/L) were also increased. Edrophonium test was positive. Electrophysiologically, muscle evoked potentials by repetitive motor nerve stimulation showed 13% and 50% waning in abductor pollicis brevis and deltoid muscle, respectively, at low frequency and no waxing at high frequency. Needle EMG showed fibrillation potentials and positive sharp waves in proximal muscles. Polymyositis was diagnosed by muscle biopsy which showed infiltration of lymphocytes in the endomysium and around non-necrotic muscle fibers. Upper arm muscle MRI showed multifocal high signal intensity lesions on T2-weighted images which were likely related to myositis. This finding is atypical for polymyositis. X-ray and CT of chest showed a mass lesion in the left pulmonary hilum, which was histologically diagnosed as type B1 thymoma. Thus, the present case had myasthenia gravis, polymyositis, thyroidititis and eosinophilia associated with type B1 thymoma. After the thymectomy, corticosteroid administration and immunoadsorption therapy, clinical symptoms and all laboratory abnormalities markedly improved. 相似文献
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A boy aged 1 month presented with profuse rectal bleeding. Chest x-ray film showed pulmonary oedema and at cardiac catheterisation infradiaphragmatic total anomalous pulmonary venous drainage to a dilated portal venous system was found. Ulcerated oesophageal varices were identified at necropsy after unsuccessful cardiac surgery. The late and unique presentation of this case is emphasised. 相似文献
468.
GL BARNES JS LUND L ADAMS A MORA SV MITCHELL A CAPLES RF BISHOP 《Journal of paediatrics and child health》1997,33(4):300-304
Objective: To conduct a phase 1 safety and tolerability trial of an oral rotavirus vaccine candidate RV3 in healthy volunteers.
Methodology: Double blind placebo controlled trial of a single 1 mL oral dose (6.5 × 105 fluorescing focus units [FFU]/mL) in 10 healthy young men, 10 3–4 year old children and 10 3 month old infants with a 4 week surveillance period. The study was undertaken at a children's hospital and nearby community in Melbourne, Australia.
Results: All subjects successfully completed the trial. There were no significant side-effects attributable to the vaccine preparation in any age group. No shedding of vaccine virus was detected by enzyme immunoassay. There was evidence of an. immune response in serum and/or gut secretions in two of five vaccinees in each age group.
Conclusion: RV3 rotavirus vaccine appears to be safe and well tolerated. Evidence of immunogenicity in some subjects after a single dose encourages further trials to determine immunogenicity after three doses, after reduction of viral dose, and without prior administration of buffer. 相似文献
Methodology: Double blind placebo controlled trial of a single 1 mL oral dose (6.5 × 10
Results: All subjects successfully completed the trial. There were no significant side-effects attributable to the vaccine preparation in any age group. No shedding of vaccine virus was detected by enzyme immunoassay. There was evidence of an. immune response in serum and/or gut secretions in two of five vaccinees in each age group.
Conclusion: RV3 rotavirus vaccine appears to be safe and well tolerated. Evidence of immunogenicity in some subjects after a single dose encourages further trials to determine immunogenicity after three doses, after reduction of viral dose, and without prior administration of buffer. 相似文献
469.
Any delivery system for bioactive molecules should have the ability to release the compound in question in a reproducible and predictable way over a certain period. For artificial skin models that are designed to enhance healing by the use of growth factors, this requirement poses another problem: the design of a delivery method that can provide a realistic assessment of the release kinetics. This means that the design should "mimic" conditions encountered in an open wound, i.e., only a certain part of the film can face the wound, from which it can absorb wound fluid that will dissolve the incorporated bioactive molecule and bring it to the open wound. Such a system has been developed and the release of 125I-labelled insulin, incorporated into flexibilized gelatin films, has been determined. The details of this study follow. 相似文献
470.
Twenty five cases of Meckel''s diverticulum were studied between 1985-1995. Eight of these were symptomatic and in the remaining 17 it was an incidental finding. The symptomatic patients presented with intestinal obstruction (5 cases), perforated peritonitis (2 cases) and intussusception (1 case). All cases of acute appendicitis were also subjected to a search for Meckel''s diverticulum. Of the 25 Meckel''s diverticuli encountered, 22 were resected and in 3 patients it was left in situ. Both the patients with perforated Meckel''s diverticulum showed ectopic gastric mucosa. Complications occurred only after surgery for symptomatic Meckel''s diverticulum. All patients undergoing incidental diverticulectomy had a smooth and uncomplicated recovery.KEYWORDS: Incidental diverticulectomy, Meckel''s diverticulum 相似文献