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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   
4.
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   
5.
The reliability and accuracy of salivary theophylline levels as a predictor of serum theophylline levels was investigated in 28 hospitalized chronic asthmatics, free of other chronic diseases, on continuous aminophylline infusion for greater than 24 hours. Twenty paired blood and saliva theophylline levels from 12 patients (group 1) were used to develop a formula for predicting serum theophylline levels from salivary levels. Twenty-one paired blood and saliva theophylline levels from 16 patients (group 2) were used to test the formula obtained. The formula predicted the serum theophylline concentration within 1.51 microgram/mL in 76% of the samples and within 1.88 microgram/mL in 100% of the samples. There was an excellent correlation between the predicted and actual serum theophylline concentrations, r = .93; thus under controlled conditions of steady-state pharmacokinetics in patients free of other diseases, salivary theophylline levels can be used to accurately predict serum levels.  相似文献   
6.
We present here a large Israeli-Arab kindred with hereditary deafness. In this family 55 deaf subjects (29M, 26F), who are otherwise healthy, have been identified and traced back five generations to one common female ancestor. The deafness is progressive in nature, usually presenting in infancy and childhood. Audiometry on six deaf and seven unaffected subjects was consistent with severe to profound sensorineural hearing loss. Based on formal family segregation analysis, the inheritance of deafness in this family closely fits the expectation of a two locus model owing to the simultaneous mutation of a mitochondrial gene and an autosomal recessive gene. Thus, this disorder appears to have the unusual features of being an inherited tissue specific mitochondrial disease and apparently requiring the homozygous presence of a nuclear gene for clinical expression. Most importantly, this disorder presents a unique opportunity to investigate the molecular basis of hereditary non-syndromic deafness and normal hearing.  相似文献   
7.
Background

One of the strictest quarantines worldwide to limit the spread of coronavirus was enforced in Jordan during the COVID-19 pandemic.

Objectives

This study investigated reported mental health and changes in lifestyle practices among Jordanian mothers during COVID-19 quarantine. The specific objectives included studying the level of depression, anxiety, and stress symptoms and their potential statistical associations with demographic and lifestyle variables. Furthermore, the study aimed to investigate differences in mental health between different demographic and socio-economic groups and to examine the major lifestyle changes that occurred on mothers during the quarantine.

Methods

An online survey was developed and administered to 2103 mothers. Participants were asked to complete a sociodemographic data form, Depression, Anxiety, and Stress Scale (DASS-21), and a lifestyle section comparing the life of mothers before and during the quarantine. Reported scores of depression, anxiety, and stress were calculated and compared across different levels of demographics including income, education level, employment status, and city of residence.

Results

This study found that mothers with lower income, lower education, not employed, or living in cities outside the capital of Jordan reported having more depression, anxiety, and stress symptoms (p < .005). Changes in their lifestyle practices included weight gain, increased time allocated for teaching children at home, increased familial violence at home, and increased time allocated for caring for their family members (average increase of 5 hours daily).

Conclusions for Practice

The unprecedented times of quarantine have put mothers in unprecedented reported mental health problems. Providing psychological support to this group might be a priority.

  相似文献   
8.
We aimed to evaluate the learning curve of the surgically standardised ‘Omega Sign’ anatomical endoscopic enucleation (AEEP) of the prostate surgery technique for junior surgeons. This study is a retrospective comparison of cases that underwent AEEP by a mentor surgeon and three junior surgeons who have completed their learning curve. A video-based laser enucleation of the prostate assessment tool (LEAT) composed of 8 steps of the technique was used to assess a senior surgeon and junior surgeons’ surgical compatibility and consistency. The surgeon who defined Omega Sign technique was determined as group 1, and cases by three junior surgeons were identified as group 2. The end points were to assess the reproducibility and repeatability and operative post-operative outcomes of the technique. 55 patients’ videos were rated by five experienced endourologists. There was no significant difference in LEAT scores between the groups among all steps. The most symmetry was found in the 1st and 3rd steps. Inter-rater consistency was also high for each step, with no statistically significant difference between the evaluators. The standardised anatomical ‘Omega Sign’ technique is reproducible for the junior surgeons. The operative steps can be performed with high consistency, and the functional and perioperative outcomes are comparable with the senior surgeon.  相似文献   
9.
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   
10.
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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