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31.
Patients with primary immunodeficiencies such as the Wiskott-Aldrich syndrome (WAS) are prone to develop Epstein-Barr virus (EBV) related lymphoproliferative disorders (LPDs). EBV LPD is most frequently seen in patients receiving immunosuppressive treatment after organ transplantation (post-transplant lymphoproliferative disorder), but can also arise in the primary immunodeficiencies. Typically, EBV LPD presents as a diffuse systemic disease with lymphadenopathy and organ involvement. A rare angiocentric and angiodestructive form of EBV associated B cell LPD, lymphomatoid granulomatosis (LyG), has also been reported in association with WAS. LyG most commonly involves the lung, but can also be seen in brain, kidney, liver, and skin. This report describes the case of a 16 year old boy with WAS who presented with an isolated non-healing ulcerating skin lesion. Biopsy revealed an EBV related LPD with the histological features of LyG. This cutaneous lesion responded dramatically to treatment with specific anti-CD20 immunotherapy and the patient remains clinically free of LPD at 18 months.  相似文献   
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Several studies have reported previously that acute myeloid leukemia (AML) may express WT1 detected by RT-PCR and/or Northern blotting. The diagnostic utility of WT1 expression in AML using immunohistochemistry has not been reported previously. Paraffin-embedded tissue sections from 55 AML, 12 acute lymphoblastic leukemia (ALL), and 10 normal bone marrow specimens were immunostained for WT1 (anti-N terminus antibody). 22/55 AML cases (40%) demonstrated nuclear immunopositivity for WT1, including 20/47 bone marrow trephines and 2/4 granulocytic sarcomas. All the ALL and normal bone marrow specimens were negative. A significant proportion of AML expresses nuclear immunostaining for WT1, a finding that has only been described previously in Wilms' tumor and desmoplastic small round cell tumor. This finding is important for the correct interpretation of immunohistochemical findings in the diagnosis of “small round cell” tumors of childhood, especially in cases of extramedullary deposits of AML, in which traditional myeloid markers may be negative.  相似文献   
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Baird  DM; Royle  NJ 《Human molecular genetics》1997,6(13):2291-2299
A high level of sequence polymorphism combined with linkage disequilibrium has created a limited number of highly diverged haplotypes across the human Xp/Yp telomere junction region. To gain insight into the unusual genetic characteristics of this region, we have examined the orthologous sequences in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla) and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp sequence is higher (average 2.6-fold) than that observed at other loci. The position of the human Xp/Yp telomere is unique, as additional sequences are present at this location in the other three species. These included an array of subterminal satellite in the chimpanzee and, in the gorilla a small interstitial array of telomere-like repeats followed by sequences with strong homology to the human 18p subterminal region. In the orang-utan, two alleles with different structures were identified. These differ by the presence or absence of a short interspersed nuclear element (SINE) sequence just proximal to long arrays of telomere-like repeat sequences that probably represent the proximal end of the orang-utan Xp/Yp telomere. In addition, a high level of sequence divergence between the two orang-utan structures was identified. This divergence is similar to that observed between the human Xp/Yp telomere-adjacent haplotypes. The high sequence divergence and evidence of gross rearrangements indicate that the Xp/Yp telomeric region has evolved faster than the rest of the genome.   相似文献   
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Inflammatory myofibroblastic tumor (IMT), previously described as inflammatory pseudotumor, can occur at any age but is a recognized soft tissue tumor of childhood. Less than 10 previous cases have been described of IMT affecting the heart, in patients ranging from 5 months to 17 years of age. We present three unusual, but similar, cases of IMT in infants, which were all predominantly intravascular in location, one of which was associated with death due to angiodestructive lesions of the coronary and cerebral arteries. These cases demonstrate an apparently distinct phenotype, with a predominant intravascular location of the tumor. Furthermore, this series highlights the difficulty in categorizing such lesions as benign versus malignant on histological grounds alone. IMT should be considered in the differential diagnosis of unusual pediatric intravascular spindle cell lesions.  相似文献   
38.
Maternal serum inhibin A and free β human chorionic gonadotrophin (β-hCG) were measured in 759 chromosomally normal, pregnant women at 10–14 weeks of gestation. There were nine who subsequently developed pre-eclampsia and in these women the maternal serum inhibin A concentration was significantly higher than in the normotensive controls.  相似文献   
39.
Three hundred and ninety-six babies born in Sheffield between 1982 and 1990 identified as being at "very high risk" of unexpected infant death by means of a scoring system, received an intensive programme of health care including a case discussion between a paediatrician, the GP and the health visitor held in the family doctor's surgery, weekly visits from the health visitor and informal hospital admission. Significantly fewer sudden unexpected infant deaths occurred in this group than were expected by logistic regression anlysis or occurred in the best available control group with comparable scores ( p = 0.024). Problems in evaluation include identification of an adequate control population, ethical difficulties in introducing a controlled study when the programme is already perceived as effective, and the calculation of "expected death rates". The results of this study indicate that very energetic programmes of intervention may prevent some deaths in vulnerable infants.  相似文献   
40.
To determine the outcome of congenital lung abnormalities, data were collected retrospectively between January 1991 and December 1996 on any foetus found to have a lung lesion on antenatal ultrasound. A total of 23 foetuses had lung lesions on antenatal ultrasound. In two foetuses the antenatal ultrasound showed bilateral enlarged "bright" echogenic lungs with evidence of hydrops. Both pregnancies were terminated and tracheal atresia was confirmed. In 15 foetuses the antenatal ultrasound appearance was of a unilateral "bright" echogenic lung. There was one case of bronchial atresia and two cases of congenital lobar emphysema, which all had surgery. In nine cases there was a reduction in the size of the lesion on serial antenatal ultrasounds and no lesion was detected after birth. In three cases a small lesion was present after birth on chest radiography. In six foetuses the antenatal ultrasound appearance was of unilateral cystic or mixed cystic and echogenic lung lesions. Two pregnancies were terminated; both had congenital cystic adenomatoid malformation. Four pregnancies were continued and three infants had surgery soon after birth and were confirmed to have had congenital cystic adenomatoid malformation. One infant has been managed conservatively. In conclusion, a definitive diagnosis cannot usually be made antenatally. A large lesion on initial scan does not necessarily predict a poor outcome. The natural history of small asymptomatic postnatal lesions is unknown and a long-term prospective study is needed to determine the outcome of these lesions.  相似文献   
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