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31.
Classical and anaplastic seminoma: difference in survival   总被引:1,自引:0,他引:1  
Bobba  VS; Mittal  BB; Hoover  SV; Kepka  A 《Radiology》1988,167(3):849-852
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma.  相似文献   
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The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods.  相似文献   
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Comparison of the results of tuberculin diagnosis in patients with tuberculosis during two studies made by the same procedure in 1973 and 1998 showed a marked increase in delayed hypersensitivity, which is indicative of higher sensitization in persons inoculated with Mycobacterium tuberculosis. This appears to be associated with the higher frequency and spread of exogenous reinfections and with the increased virulence of the causative agent.  相似文献   
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Studies were made of the effects of various classes of lipoproteins (LP) from the blood of rabbits with experimental hypercholesterolemia and human subjects with pronounced atherosclerosis on the vascular tone of rat thoracic aorta specimens. In hypercholesterolemia, there was a considerable weakening of a vasodilatory action of atherogenic LP fractions--LDL and VLDL. A vasodilatory effect of HDLP was not changed. In subjects suffering from atherosclerosis vasodilatory effects of both atherogenic and antiatherogenic HDLP decreased significantly. The revealed changes were related to shifts in lipid and protein components of LP complexes manifesting in the development of dyslipoproteinemia and dysapoproteinemia. In atherosclerosis accompanied with more profound changes suppression of vasodilatory effects of LP is greater than in transient experimental hypercholesterolemia. Consequently, changes of lipid and apo composition of LP and weakening of their vasodilatory action play a considerable role in the vessel tone changes in atherogenic situation.  相似文献   
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Examination of 42 first-year students from the Pomor State University in Arkhangelsk has shown that 61.91% of them had obvious signs of social disadaptation and high reactive and personality anxiety and 38.09% had no social disadaptation with low and moderate anxiety. Examination was performed in the intersession period. Students with phenomena of social disadaptation displayed reduced functioning of basic cognitive mental processes: memory, thinking, attention. The individual properties predisposing to disadaptation were as follows: instability of central nervous system performance and the personality features were hypersensitivity, sensitiveness, emotional liability, some demonstrativeness in behavior, high anxiety, inclination to phobias. The detected changes in cognitive mental processes show it necessary to develop and to introduce comprehensive sociopsychological rehabilitative programmes for students of higher educational establishments for early assessment and adequate correction of social disadaptation phenomena.  相似文献   
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The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings.  相似文献   
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