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Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.  相似文献   
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A relationship between teething and fever was sought by examining mothers' reports of the 20 days before the eruption of the first tooth in 46 healthy infants. Twenty infants had a fever of greater than 37.5 degrees C on day 0 compared with seven infants (or fewer) from day 19 to day 4. The danger of attributing fever to teething is emphasised.  相似文献   
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Measurement of dialysis adequacy in patients with end-stage renal disease involves the use of urea kinetic modeling, which is a reflection of both dietary protein intake and efficiency of small solute clearance. Different dialytic modalities are available for patients in acute renal failure, including intermittent hemodialysis, continuous renal replacement therapies and peritoneal dialysis. In recent years, there has been a growing effort to measure dialysis adequacy in patients with acute renal failure using urea kinetic modeling. This initiative has been driven by the persistently high mortality rates in patients with dialysis-requiring acute renal failure, which may partly be related to inadequate dialysis dosing. In the setting of acute renal failure, dialysis adequacy has been measured using both single-pool and double-pool urea kinetics, as well as blood-based and dialysate-based urea kinetic modeling. Unfortunately, current goals and methods of measuring dialysis adequacy have been extrapolated from the end-stage renal disease patient population. These extrapolations are problematic because of differences in total body water, protein catabolic rate, and vascular access. Continuous renal replacement therapy has theoretical advantages over intermittent hemodialysis, including a decreased tendency to induce hypotension, and improved solute clearance and fluid removal, while allowing intensive nutritional support, and a better clearance of medium- to large-size molecules. The latter may play a significant role in patients with sepsis-associated acute renal failure. To date, comparative studies are scant and equivocal in establishing the superiority of a particular dialysis dose or modality.  相似文献   
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Although several adaptive mechanisms have been identified that mask the existence of Parkinson's disease and delay the onset and aggravation of motor symptoms, the timescale and implications of this compensatory process remain an enigma. In order to examine: (i) the nature of the dopaminergic adaptive mechanisms that come into action; (ii) their sequential activation in relation to the severity of degeneration; and (iii) their efficacy with regard to the maintenance of a normal level of basal ganglia activity, we analysed the brains of mice treated daily with 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP, 4 mg/kg, i.p.) and killed at 5-day intervals from day 0 (D0) to D20. Our results demonstrate the sequential activation of two compensatory mechanisms: (i) an increase in striatal tyrosine hydroxylase (TH) protein content attested by the persistence of TH immunolabelling up to D15, contrasting with the decrease observed in both the number of nigral TH-immunoreactive neurons (-70.2%) and striatal dopamine content (-38.4%); (ii) a downregulation of DA uptake in surviving terminals at D20 (73.4% of nigral degeneration). At this point, the failure of adaptive mechanisms to maintain striatal dopaminergic homeostasis is also illustrated by an increase in the cytochrome oxidase activity of substantia nigra pars reticulata, a marker of neuronal function. It has been postulated that an increase in dopamine release per pulse could constitute an adaptive mechanism. The data we present from our MPTP mice model infirm this hypothesis. This study explores the link between the degree of nigral degeneration and the sequential activation of dopaminergic compensatory mechanisms in the nigrostriatal pathway and, in so doing, proposes a rethink of the paradigm applied to these mechanisms.  相似文献   
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Augmentation pharyngoplasty, in which tissue filler or grafts are used to augment the posterior nasopharynx, is an accepted option to treat velopharyngeal insufficiency. It is generally well tolerated and safe with limited side effects. In this study, we describe a case of a retropharyngeal abscess and Grisel syndrome following hyaluronic acid augmentation pharyngoplasty. Grisel syndrome is a serious condition that requires early diagnosis and prompt intervention to prevent further complications.  相似文献   
8.
We estimate the prevalence and type of urinary incontinence (UI), possible associated risk factors, and the impact of UI on women's social and psychological well-being. The sample consisted of women attending a family medicine clinic at Jordan University Hospital (JUH) who answered a self-administered questionnaire. More than one-third of the sample reported the presence of UI. Stress type was the most frequently reported risk factor, followed by mixed incontinence, then urge. Age, diabetes, chronic cough, parity, and hysterectomy were positively associated with the presence of UI. Incontinence caused low self-esteem in more than half of the women who experienced it.  相似文献   
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Few studies deal with thromboembolic complications in burn patients. The review of the literature and current practice in burn centres point out low, average and high-risk patients, according to the characteristics of the burns wounds. In case of average risk, low molecular weight heparin prophylaxis is suggested. In high risk patients, low molecular weight heparin therapy or continuous intravenous heparin are recommended. This prevention should be continued until the recovery of a normal mobility and complete resolution of inflammation.  相似文献   
10.
Background The value of re-exploration for pancreatic ductal adenocarcinoma after the initial diagnosis of unresectability is unclear. Methods In this study, we analyzed 33 patients who were re-explored after an initial diagnosis of unresectability. Results At the time of reoperation, a resectable tumor was found in 18 patients: therefore, 15 pancreaticoduodenectomies, two total pancreatectomies and one left resection were performed with three vascular resections. Morbidity and mortality rates for the cohort were 6/33 and 1/33, without significant differences between resectable and nonresectable patients. Length of stay, duration of operation, and blood loss were significantly increased in the resection group. Kaplan–Meier survival analysis demonstrated increased median survival for resected patients (1078 days after the initial operation versus 547 days in the group of unresectable patients; p = 0.018). Analysis of the reasons against initial resection showed that, if the patients had been sent to a tertiary referral center for pancreatic surgery, a different decision in favor of resection would probably have been made in 14 out of 33 patients. A review of 10 published reports on reoperation for pancreatic cancer revealed results comparable to our study in terms of low morbidity and mortality as well as a survival benefit. Conclusions Reoperation for pancreatic ductal adenocarcinoma that is initially deemed unresectable can be safely performed in a selected group of patients by experienced surgeons, supporting the concept of patient centralization in pancreatic surgery. Resection at the second operation may confer a survival benefit even when the initial findings preclude a potentially curative approach.  相似文献   
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