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41.
Retrorectal cystic hamartomas (RCH) are rare congenital lesions of the presacral space, of which 68 cases are reported under different terms. Clinicopathologic features are usually constant and similar to the present case. A 23-year-old woman complained of abdominal and perineal pains for several months. Physical examination revealed a nodular mass in the posterior part of the rectum. A pelvic MRI showed a 5.5 cm cystic retrorectal mass compressing the rectum. The patient underwent surgical resection. Pathologic examination found an ill-defined nodular mass, composed by numerous cysts surrounded by fibroadipose tissue. Cysts were lined by different epithelia: keratinized and non keratinized squamous, transitional, ciliated and mucus-producing columnar epithelia. Few mucinous glands were noted, connected to some cysts. These epithelial structures were surrounded by connective tissue in which well-differentiated bundles of smooth muscle fibers were present without well-formed muscularis. The RCH differential diagnosis includes principally congenital cysts: epidermal cysts, cystic teratomas, dermoid cysts, anal gland cysts and rectal duplications. An embryologic origin of RCH from remnants of the postanal gut is currently accepted. Loco-regional inflammatory process frequently complicates this lesion and can cause perirectal fistulae. RCH also possesses a malignancy potential, with development of adenocarcinomas. To avoid these complications, complete excision is recommended.  相似文献   
42.
Primary central nervous system lymphoma (PCNSL) is a rare disease. A small number of cytogenetic studies of PCNSL have been conducted and several reports have been published on associated molecular and protein expression data. We combined these approaches in a series of eight PCNSL cases, analyzing the chromosomal abnormalities using comparative genomic hybridization (CGH), testing for Epstein Barr virus (EBV) involvement by in situ hybridization for EBER, assessing expression of p53, Bcl-2, Bcl-6 and CD10 by means of immunohistochemistry, and screening for mutations of the TP53 gene by DGGE. TP53 gene mutations and EBV expression were not detected. Most of the cases showed p53, Bcl-6 and Bcl-2 protein expression. CGH revealed DNA copy number changes in all eight cases. The most frequent changes were gains of chromosome 12 (63%), chromosome 18 (50%) and 20q (38%), and loss of chromosome arm 6q (75%). No correlation between protein expression and chromosomal abnormalities was found in these eight cases. Although gains of chromosome 12, 18 and 20q and loss of 6q have also been reported in systemic diffuse large B-cell lymphomas, the frequency of 6q deletion is clearly higher in PCNSL. This creates a similarity to primary lymphomas of the testes that also frequently have deletions of 6q. This suggests that suppressor genes located on chromosome 6q may play a role in the development of lymphomas at immunoprivileged sites, like the CNS.  相似文献   
43.
Background: The clinical demarcation of the syndrome progressive myoclonus ataxia is unclear, leading to a lack of recognition and difficult differentiation from other neurological syndromes. Objectives: The objective of this study was to apply a refined definition of progressive myoclonus ataxia and describe the clinical characteristics in patients with progressive myoclonus ataxia and with isolated cortical myoclonus. Methods: A retro‐ and prospective analysis was performed in our tertiary referral center between 1994 and 2014. Inclusion criteria for progressive myoclonus ataxia patients were the presence of myoclonus and ataxia with or without infrequent (all types, treatment responsive) epileptic seizures. Inclusion criteria for isolated cortical myoclonus was the presence of isolated cortical myoclonus. Clinical and electrophysiological characteristics data were systematically scored. Results: A total of 14 progressive myoclonus ataxia patients (males, 7; females, 7), median age 14.5 years, and 8 isolated cortical myoclonus patients (males, 2; females, 6), median age 23.5 years, were identified. In 93% of the progressive myoclonus ataxia patients, ataxia started first (median 2 years) followed by myoclonus (4 years) and finally infrequent epilepsy (9.3 years), with a progressive course in 93%. In 64% of the progressive myoclonus ataxia patients, a genetic underlying etiology was identified, including 3 not earlier reported causative progressive myoclonus ataxia genes. In isolated cortical myoclonus patients, myoclonus started at (median) 12 years with progression over time in 63% and a single epileptic seizure in 1 patient. No genetic causes were identified. Conclusion: Using a refined definition, we could create a rather homogenous progressive myoclonus ataxia group. Patients with isolated cortical myoclonus have a different course and do not appear to evolve in progressive myoclonus ataxia. The refined progressive myoclonus ataxia definition is a successful first step toward creating a separate syndrome for both clinical practice and future genetic research. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.  相似文献   
44.
Frontotemporal lobar degeneration (FTLD) is a clinically, genetically and pathologically heterogeneous disorder. Within FTLD with ubiquitin-positive inclusions (FTLD-U), a new pathological subtype named FTLD-FUS was recently found with fused in sarcoma (FUS) positive, TDP-43-negative inclusions, and striking atrophy of the caudate nucleus. The aim of this study was to determine the frequency of FTLD-FUS in our pathological FTLD series, and to describe the clinical, neuroimaging and neuropathological features of FTLD-FUS, especially caudate atrophy. Demographic and clinical data collected prospectively from 387 patients with frontotemporal dementia (FTD) yielded 74 brain specimens. Immunostaining was carried out using a panel of antibodies, including AT-8, ubiquitin, p62, FUS, and TDP-43. Cortical and caudate atrophy on MRI (n = 136) was rated as normal, mild-moderate or severe. Of the 37 FTLD-U cases, 33 were reclassified as FTLD-TDP and four (0.11, 95%: 0.00–0.21) as FTLD-FUS, with ubiquitin and FUS-positive, p62 and TDP-43-negative neuronal intranuclear inclusions (NII). All four FTLD-FUS cases had a negative family history, behavioural variant FTD (bvFTD), and three had an age at onset ≤40 years. MRI revealed mild-moderate or severe caudate atrophy in all, with a mean duration from onset till MRI of 63 months (range 16–119 months). In our total clinical FTD cohort, we found 11 patients (0.03; 95% CI: 0.01–0.05) with bvFTD, negative family history, and age at onset ≤40 years. Caudate atrophy was present in 10 out of 136 MRIs, and included all four FUS-cases. The newly identified FTLD-FUS has a frequency of 11% in FTLD-U, and an estimated frequency of three percent in our clinical FTD cohort. The existence of this pathological subtype can be predicted with reasonable certainty by age at onset ≤40 years, negative family history, bvFTD and caudate atrophy on MRI.  相似文献   
45.
Digital imaging of the chest   总被引:4,自引:0,他引:4  
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.  相似文献   
46.
47.
Effect of warm-up on cycle time trial performance   总被引:2,自引:0,他引:2  
PURPOSE: This study was designed to determine the effect of warm-up on 3-km cycling time trial (TT) performance, and the influence of accelerated VO(2) kinetics on such effect. METHODS: Eight well-trained road cyclists, habituated to 3-km time trials, performed randomly ordered 3-km TT after a) no warm-up (NWU), b) easy warm-up (EWU) (15 min comprised of 5-min segments at 70, 80, and 90% of ventilatory threshold (VT) followed by 2 min of rest), or c) hard warm-up (HWU) (15 min comprised of 5-min segments at 70, 80, and 90% VT, plus 3 min at the respiratory compensation threshold (RCT) followed by 6 min of rest). VO(2) and power output (SRM), aerobic and anaerobic energy contributions, and VO(2) kinetics (mean response time to 63% of the VO(2) observed at 2 km) were determined throughout each TT. RESULTS: Three-kilometer TT performance was (P < 0.05) improved for both EWU (266.8 +/- 12.0 s) (-2.8%) and HWU (267.3 +/- 10.4 s) (-2.6%) versus NWU (274.4 +/- 12.1 s). The gain in performance was predominantly during the first 1000 m in both EWU (48% of gain) and HWU (53% of gain). This reflected a higher power output during the first 1000 m in both EWU (384 W) and HWU warm-up (386 W) versus NWU (344 W) trials. The mean response time was faster in both EWU (45 +/- 10 s) and HWU (41 +/- 12 s) versus NWU (52 +/- 13 s) trials. There were no differences in anaerobic power output during the trials, but aerobic power output during the first 1000 m was larger during both EWU (203 W) and HWU (208 W) versus NWU (163 W) trials. CONCLUSIONS: During endurance events of intermediate duration (4-5 min), performance is enhanced by warm-up irrespective of warm-up intensity. The improved performance is related to an acceleration of VO(2) kinetics.  相似文献   
48.
PURPOSE: To evaluate the use of a computer-aided detection (CAD) system (designed for mammographic mass detection) to help improve mass interpretation and to compare CAD results with independent double-reading results. MATERIALS AND METHODS: Screening mammograms from 500 cases were collected; 125 of these cases were screening-detected cancers, and 125 were interval cancers. Previously obtained screening mammograms (ie, prior mammograms) were available in all cases. All mammograms were analyzed by a CAD system, which detected mass regions and assigned a level of (cancer) suspicion to each mass. Ten experienced screening radiologists read the prior mammograms. For independent interpretation with CAD, the suspicion rating assigned to each finding by the radiologist was weighted with the CAD output at the area of the finding. CAD markers on areas that were not reported by the radiologist were not used. Independent double reading was implemented by using a rule to combine the levels of suspicion assigned to findings by two radiologists. Results were evaluated by using localized-response receiver operating characteristic analysis. RESULTS: In a total of 141 cases, there was a visible abnormality at the location of the cancer on the prior mammogram, and 115 of these were classified as mass cases. For prior mammograms that depicted masses, the mean sensitivity of the radiologists, as averaged among the false-positive rates lower than 10%, was 39.4%; this increased by 7.0% with CAD and by 10.5% with double reading. Differences among single, double, and CAD readings were statistically significant (P <.001). CONCLUSION: Although independent double reading yields the best detection performance, the presence and probability of CAD mass markers can improve mammogram interpretation.  相似文献   
49.
To standardize the maximal static force (Fo) of the arm flexors, the accuracy of an anthropometric method for estimating the mid-arm cross-sectional muscle and bone area (MBA) was investigated. This was done by comparing the anthropometrically determined area (MBA.A) with the area measured by means of computerized tomography (MBA.S). In the same way, the accuracy of Heymsfield's equations (Heymsfield et al., 1982) for predicting MBA (MBA.H) from anthropometric measures was tested. MBA.A was significantly larger than MBA.S, the relative difference increasing with the thickness of the subcutaneous fat layer. This difference was attributed to a 27% underestimation of the fat layer thickness as measured with the skinfold caliper. Women being fatter than men, this caused the standardized maximal static force (Fo/MBA) to be lower in women than in men. MBA.H was 12% smaller than MBA.S. This may have been due to a difference in the way of measuring the arm circumference between the present authors and Heymsfield et al.  相似文献   
50.
Having a relative with an eating disorder (ED) affects the life of family caregivers and may thus affect their quality of life. To study this aspect, 40 caregivers of ED patients filled out a health-related quality of life questionnaire (Short Form-36) and a questionnaire on the impact of the ED on various areas of life domains, and on the relationship with the ED patient and the need for professional support. Quality of life of caregivers was worse than in a normal reference group. Specifically, mental health, vitality and emotional role functioning were reported to be most impaired. ED appeared to affect families’ lives substantially. In response to the ED, caregivers felt anxious, powerless, sad, or desperate. The relationship of the caregiver with the ED patient had also changed. Caregivers were more worried, lost their trust, and reported more conflicts. Seventy five percent welcomed professional support. Caregivers need practical advice, information on ED, and emotional support. Quality of life of caregivers should be addressed in the treatment of ED.  相似文献   
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