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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.
AIMS--To evaluate a safe sputum processing method for detection of tuberculosis in developing countries. METHODS--A sample processing method was developed in which acid fast bacilli were killed with 1% sodium hypochlorite and concentrated by flotation on a layer of xylene before staining by the Ziehl Neelsen or auramine O methods. RESULTS--Best results were obtained by auramine O staining after flotation. Staining by the Ziehl Neelsen method after flotation gave better results than direct Ziehl Neelsen staining without flotation. CONCLUSIONS--The flotation method with Ziehl Neelsen staining offers advantages for smear preparation in the tuberculosis control programmes of developing countries.  相似文献   
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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   
8.
Currently, there are 18 different religious communities living in Lebanon. While evolving primarily within Lebanon, these communities show a level of local isolation as demonstrated previously from their Y-haplogroup distributions. In order to trace the origins and migratory patterns that may have led to the genetic isolation and autosomal clustering in some of these communities we analyzed Y-chromosome STR and SNP sample data from 6327 individuals, in addition to whole genome autosomal sample data from 609 individuals, from Mount Lebanon and other surrounding communities. We observed Y chromosome L1b Levantine STR branching that occurred around 5000 years ago. Autosomal DNA analyses suggest that the North Lebanese Mountain Maronite community possesses an ancestral Fertile Crescent genetic component distinct from other populations in the region. We suggest that the Levantine L1b group split from the Caucasus ancestral group around 7300 years ago and migrated to the Levant. This event was distinct from the earlier expansions from the Caucasus region that contributed to the wider Levantine populations. Differential cultural adaption by populations from the North Lebanese Mountains are clearly aligned with the L1b haplotype STR haplogroup clusters, indicating pre-existing and persistent cultural barriers marked by the transmission of L1b lineages. Our findings highlight the value of uniparental haplogroups and STR haplotype data for elucidating biosocial events among these populations.Subject terms: Population genetics, Computational biology and bioinformatics  相似文献   
9.
DNA microarrays are a powerful experimental tool for the detection of specific genomic sequences and are invaluable to a broad array of applications: clinical diagnosis, personalized medicine, drug research and development, gene therapy, food control technologies, and environmental sciences. Alloimmunization to human platelet antigens (HPAs) is commonly responsible for neonatal alloimmune thrombocytopenia, post-transfusional purpura and platelet transfusion refractoriness. Using DNA microarrays, we developed a diagnosis to type the biallelic HPA-1 platelet group. The region for the human genomic DNA sequence that contains the polymorphism responsible for HPA-1 alleles was amplified by polymerase chain reaction (PCR). The expected DNA fragments were hybridized on DNA microarrays, and the data were analyzed using specially developed software. Our initial results show that the two HPA-1 antigens polymorphisms containing a single base difference were detected using DNA microarrays.  相似文献   
10.
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.

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