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AJ van Geest† PJM Berretty† PJJM Klinkhamer‡ HAM Neumann§ 《Journal of the European Academy of Dermatology and Venereology》2002,16(5):529-531
BACKGROUND: Acquired cerebriform intradermal naevus (CIN) is a rare form of pseudo cutis verticis gyrata. CASE REPORT: A case of acquired CIN of the scalp in a 46-year-old male patient is presented. The clinical and histopathological presentations of CIN are described and the therapeutic possibilities are discussed. CONCLUSIONS: In each individual case the physician must decide whether to do surgery or follow a wait-and-see policy. There is little risk of malignant change of CIN, and surgical excision of such lesions often involves evident mutilation. 相似文献
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AE Boothroyd BVS Murthy A Darbyshire AJ Petros 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(12):1422-1425
Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2 O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced. 相似文献
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Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
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Congenital mesoblastic nephroma: possible prognostic and management value of assessing DNA content. 总被引:1,自引:0,他引:1 下载免费PDF全文
J C Barrantes C Toyn K R Muir S E Parkes F Raafat A H Cameron H B Marsden J R Mann 《Journal of clinical pathology》1991,44(4):317-320
The case records and pathology of all children with kidney tumours treated in the West Midlands Health Authority Region (WMHAR) from 1957 to 1986 were reviewed. The histology was reviewed by a panel of three paediatric pathologists. Thirteen (6%) out of 211 cases were considered to have congenital mesoblastic nephroma (CMN). Nine were of the conventional type, three of the atypical cellular type, and one mixed. DNA ploidy was investigated and showed two of the tumours to be aneuploid and nine diploid (tissue was not available in the two other cases). The two aneuploid tumours were of atypical cellular and mixed histology, respectively; the diploid tumours were of the conventional type in eight cases and atypical cellular in one. The atypical cellular type has been reported to behave more aggressively, but the benefit of additional treatment after surgery to prevent recurrence remains unclear. Measurement of DNA content by flow cytometry, together with histological subclassification, may be useful in selecting patients who will benefit from further treatment after surgery. 相似文献
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R. N. Lemon R. B. Muir G. W. H. Mantel 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,66(3):621-637
Summary Corticomotor (CM) neurones were identified in three conscious macaque monkeys by the presence of post-spike facilitation (PSF) in spike-triggered averages of e.m.g. recorded from intrinsic hand and forearm muscles during performance of a precision grip task. Post-spike effects were compared with those produced by single-pulse intracortical microstimulation (ICMS), with strengths of 4–20 A, delivered at the site of 47 CM cells. Most muscles facilitated by a CM cell were also facilitated by ICMS at the site of the cell. ICMS effects were stronger: at 10 A, the amplitude of ICMS-evoked facilitation was on average 2.8 times greater than PSF, and 6.9 times greater at 20 A. Onset latency of ICMS-evoked facilitation was consistently longer (by 1.7 and 1.3 ms at 10 and 20 A respectively) than PSF, and it is suggested that this results from the indirect, trans-synaptic excitation of CM cells by ICMS. Post-spike suppression was rarely seen (7/421 compared to 105/421 cases of PSF). In contrast, suppression and facilitation were equally common in response to ICMS. The synaptic mechanisms underlying these effects were explored in 5 anaesthetised macaque monkeys. ICMS facilitated a greater proportion of the tested muscles than did the CM cell recorded at the stimulus site. The results suggest the juxtaposition in the motor cortex of CM neurones with different muscle fields. The merits of STA and ICMS for exploring cortical organisation are discussed. 相似文献
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