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91.

Purpose

To investigate the correlation between the degree of hepatic, splenic, pancreatic, vertebral bone marrow (VBM), and myocardial siderosis, as expressed by relaxation rate (R2 = 1/T2) values, in patients with thalassemia.

Materials and Methods

R2 relaxation rate values of liver, spleen, VBM, pancreas, and myocardium were estimated in 68 consecutive transfusion‐dependent patients with β‐thalassemia major and 10 healthy controls using a respiratory triggered 16‐echo Carr‐Purcell‐Meiboom‐Gill (CPMG) spin echo sequence.

Results

Hepatic R2 values were significantly increased in all 68 patients; VBM, pancreatic, and myocardial R2 values were increased in 67/68, 35/47, and 47/61 patients, whereas five patients showed decreased pancreatic R2 attributed to fatty degeneration. Of the 39 nonsplenectomized patients, splenic R2 values were decreased in 30 and normal in nine patients. Hepatic R2 values correlated with splenic (r = 0.63, P < 0.001), VBM (r = 0.52, P < 0.001), but not with myocardial and pancreatic R2 values.

Conclusion

Despite positive correlations between the degree of hepatic, splenic, and VBM siderosis, as expressed by respective R2 values, there was variability of iron distribution patterns in thalassemic patients. Unpredictable patterns of iron distribution may be seen, such as normal signal of the spleen in the presence of siderotic liver, resembling primary hemochromatosis. Fatty degeneration of the pancreas was not uncommon. J. Magn. Reson. Imaging 2009;29:853–859. © 2009 Wiley‐Liss, Inc.  相似文献   
92.
OBJECTIVE: Transiently evoked (TEOAEs) and distortion-product otoacoustic emissions at the 2f1-f2 frequency (DPOAEs) are being used as a clinical tool for diagnosis of peripheral auditory pathology. Because both tests are fast and non-invasive, they may be an excellent method for hearing screening in infants and children. The purpose of this study was to compare the TEOAE and DPOAE measures obtained in a group of healthy children. METHODS: Sixty-six school-aged children with normal hearing were included in the study. Subjects with recent otologic disease or abnormal tympanograms were excluded. TEOAEs and DPOAEs were performed using a DP Echoport ILO 292 Otodynamics analyzer connected to a portable personal computer. Correlation between TEOAE amplitudes and DPOAE levels was estimated. RESULTS: Correlation between TEOAE amplitudes and DPOAE levels was highly significant across all measured frequencies. Correlation was more significant at the middle frequencies than at the low and high frequencies. CONCLUSIONS: Although frequency specific information may be obtained by both tests, most reliable results were obtained at the middle frequencies. TEOAE values were more prominent at low frequencies, whereas DPOAEs were more effective at high frequencies. Both methods are reliable, objective, fast and useful tests of the cochlear status and should be included in the standard audiological diagnostic work-up of children.  相似文献   
93.
We report on a small-cell lung cancer case that was heralded by the presence of CENP-B specific anti-centromere autoantibodies (ACA) detected well before the diagnosis of cancer. The patient received chemotherapy plus radiotherapy, which resulted in complete remission of the tumor. Serum ACA levels were zeroed at the time of radiological documentation of tumor response and remained undetected at serial follow-up assessments until they rose again along with documentation of tumor recurrence which occurred 12 months later. We review in brief published research and discuss anti-centromere autoantibodies as potential biomarkers in small-cell lung cancer, a highly proliferative tumor which lacks sensitive serum markers.  相似文献   
94.
95.
96.

Purpose  

The increasing availability of fluorescent probes for in vivo optical imaging enables the interrogation of complex biological processes in small animals serving as models for human-like tissue function and disease. However, the validation of probe bio-distribution during their development or the study of different disease models, in support of in vivo imaging studies, is not straightforward.  相似文献   
97.
Karantzoulis V, Liapi C & Papaggelopoulos P
(2012) Histopathology
Large‐scale bone mineral histomorphometry – report of a simplified technique Aims: The aim of this study was the development of a simplified technique for bone mineral histomorphology on large undecalcified bone samples. Established techniques, such as undecalcified bone thin sectioning, ultrathin grinding, surface‐stained block grinding and micro‐computerized tomography (CT), are expensive, time‐consuming and put very high demands on equipment, safety standards, personnel and laboratory facilities. Methods and results: The method is based on the surface‐stained block‐grinding principle; however, its novelty lies in the selection of user‐friendly, safe and low‐cost materials, equipment and digitization techniques. We describe in detail the relevant steps, as well as many practical tips for their successful implementation: accurate bone cutting in thin sections with a customized arrangement on a commercial bandsaw, defatting with sodium hypochlorite, embedding in epoxy resin blocks at room temperature, silicon carbide paper grinding, von Kossa staining, flatbed scanner digitization and image processing. Conclusion: We believe that the proposed methodology could contribute to the expansion of the study of bone tissue, as it enables the rapid examination of bone specimens on a large scale with minimal laboratory requirements and consumables costs.  相似文献   
98.
We report our results from the application of evoked electromyography (EEMG) and facial nerve latency testing (FNLT) in 30 children aged 4–14 years with idiopathic facial palsy. Our aim was to define the value of these tests as prognostic tools in Bell's palsy. From the EEMG results we ascertained that, when the amplitude of the compound muscle action potential varied between 51% and 95% of the normal value, the neuronal damage is slight (neurapraxia). When the percentage value of muscle response decreases, the prognosis is worse. The results of the FNLT showed that, when the latency is within normal limits, the damage to the nerve is slight (neurapraxia). If the latency is prolonged, the prognosis is worse. Evaluation of our results and comparison with the index of facial nerve functional recovery showed that those two tests have a high percentage of correctness (100% for the EEMG and 96.7% for the FNLT) and a low percentage of error. We conclude that these tests are excellent for predicting the outcome of facial nerve palsy in childhood and we suggest that young patents undergo both so that the determination of the lesion may be as correct as possible.  相似文献   
99.
100.
BACKGROUND AND PURPOSE: Although the standard of care for patients with locally advanced uterine cervix carcinoma is cisplatin-(CDDP-)based chemotherapy and irradiation (RT), the optimal regimen remains to be elucidated. A phase I/II study was conducted to evaluate the dose limiting toxicity (DLT) and the maximum tolerated dose (MTD) of liposomal doxorubicin (Caelyx) combined with CDDP and RT for cervical cancer. PATIENTS AND METHODS: 24 patients with stage IIB-IVA were enrolled (Table 1). They all received external RT (up to 50.4 Gy) and two medium-dose rate (MDR) brachytherapy implants (20 Gy each at point A). The Caelyx starting dose of 7 mg/m2/week was increased in 5-mg/m2 increments to two levels. The standard dose of CDDP was 20-25 mg/m2/week. RESULTS: Concurrent chemoradiation (CCRT) sequelae and the DLTs (grade 3 myelotoxicity and grade 3 proctitis in five patients treated at the 17 mg/m2/week Caelyx dose level) are shown in Tables 2, 3, 4, and 5. After a median follow-up time of 17.2 months (range 4-36 months), four patients had died, 15 showed no evidence of progressive disease, and five (20.8%, 95% confidence interval [CI]: 12.5-29.1%) were alive with relapse (Figure 1). There were seven complete (29.1%, 95% CI: 19.8-38.4%) and 17 partial clinical responses (95% CI: 61.1-80.1%). The median progression-free survival was 10.4 months. Causes of death were local regional failure with or without paraaortic node relapse combined with distant metastases (Table 6). CONCLUSION: Conclusion: The MTD of Caelyx given concurrently with CDDP and RT was determined at the 12 mg/m2/week dose level. The above CCRT schema is a well-tolerated regimen, easy to administer in ambulatory patients, and results appear promising.  相似文献   
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