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971.
MJ Butson JN Mathur PE Metcalfe 《Journal of Medical Imaging and Radiation Oncology》1997,41(2):148-150
Skin-sparing properties of megavoltage photon beams are compromised by electron contamination. Higher energy beams do not necessarily produce lower surface and basal cell layer doses due to this electron contamination. For a 5 ± 5cm field size the surface doses for 6 MVp and 18MVp X-ray beams are 10% and 7% of their respective maxima. However, at a field size of 40x40cm the percentage surface dose is 42% for both 6 MVp and 18 MVp beams. The introduction of beam modifying devices such as block trays can further reduce the skin-sparing advantages of high energy photon beams. Using a 10mm perspex block tray, the surface doses for 6MVp and 18MVp beams with a 5x5cm field size are 10% and 8%, respectively. At 40x40cm, surface doses are 61 % and 63% for 6MVp and 18MVp beams, respectively. This trend is followed at the basal cell layer depth. At a depth of 1 mm, 18 MVp beam doses are always at least 5% smaller than 6 MVp doses for the same depth at all field sizes when normalized to their respective Dmax values. Results have shown that higher energy photon beams produce a negligible reduction of the delivered dose to the basal cell layer (0.1 mm). Only a small increase in skin sparing is seen at the dermal layer (1 mm), which can be negated by the increased exit dose from an opposing field. 相似文献
972.
There is much evidence that the children born in the last decade of the 20th century are healthier and living longer than children born earlier this century, and that children born too small or too soon are now more likely to reach adulthood than similar children born 10 or 20 years ago. Yet measures of social disadvantage (poverty, underachievement in education, lone parenthood) are increasing, putting this generation of children at higher risk of morbidity later in life. 相似文献
973.
V Ramesh R Mountford HM Kingston A Kelsey MJ Noronha MA Clarke 《Archives of disease in childhood》1993,69(4):453-454
A boy with Duchenne muscular dystrophy and facial dysmorphism in conjunction with Klinefelter's genotype 47XXY is presented; this is an unusual situation with two genetic errors evolving over two generations. Karyotyping should be considered in boys with Duchenne muscular dystrophy who have unusual features. 相似文献
974.
Interleukin (IL)-1 and IL-2 may participate in the systemic inflammatory response and hypergammaglobulinaemia observed in patients with cystic fibrosis. Thirty seven patients with cystic fibrosis were compared with 25 normal controls. High IgG and IgM concentrations were associated with more severe pulmonary disease. IL-1 alpha and soluble IL-2 receptor concentrations were higher in the cystic fibrosis group than in the controls and also correlated with concentrations of IgG and IgM. These results suggest that these cytokines may contribute to enhanced immunoglobulin synthesis and silent inflammatory activity in clinically stable patients with cystic fibrosis. 相似文献
975.
976.
977.
Thirty-eight infants and young children with gastroenteritis were investigated for lactose malabsorption. Each of them was given an oral lactose load of either 0.5 g/kg or 2 g/kg after which breath hydrogen excretion was measured, and each was observed to see if he had clinical symptoms of lactose intolerance. Only one patient, given 2 g/kg lactose, had clinical intolerance. His breath hydrogen excretion however was negative. Three of 18 patients given 0.5 g/kg lactose had positive breath hydrogen tests. None of these was symptomatic. Lactose intolerance in gastroenteritis was rare in our study, and the hydrogen breath test was not an appropriate technique for detecting it. 相似文献
978.
Jenner MJ Micallef IN Rohatiner AZ Kelsey SM Newland AC Cavenagh JD 《Medical oncology (Northwood, London, England)》2000,17(4):333-336
A 36-year-old man underwent matched unrelated donor bone marrow transplantation for chronic myeloid leukaemia. He developed
severe hepatic veno-occlusive disease as an early post-transplant complication. Tissue plasminogen activator was initially
felt to be contraindicated since the patient had concomitant pericarditis. Defibrotide was therefore commenced as treatment
for veno-occlusive disease. The pericarditis improved but the veno-occlusive disease continued to worsen (peak bilirubin 353
μmol/I). Tissue plasminogen activator followed by a heparin infusion was therefore administered. However, he proceeded to
develop haemorrhagic cardiac tamponade that required drainage. Thrombolysis was therefore discontinued and treatment with
defibrotide resumed after an interval of 48 h. The veno-occlusive disease gradually resolved and defibrotide was discontinued
once the bilirubin had plateaued. He was discharged home on day +52 post-transplant. 相似文献
979.
A retrospective study was made of 30 children with Leber's amaurosis (congenital retinal blindness). 24 presented with severe visual impairment, typical ophalmological findings, and absent electroretinograms. 6 other children, though presenting with marked visual loss and absent electroetinograms were later shown to be less severely affected. Some of the more severely affected children had associated neurodevelopmental or renal abnormalities. 相似文献
980.
A formula is given, allowing a value for total body fat to be calculated from skinfold thickness measurements at two sites (subscapular and triceps), in conjunction with nine body dimensions. For newborn infants total body fat so calculated accorded satisfactorily with published data from cadaver analyses. The formula has been tentatively applied to infants up to the age of 40 weeks, and to preterm infants. The difference between the growth of male and female infants was analysed in a series of 27 normal infants; the greater growth of musculoskeletal tissue in the male contrasted with the relatively greater growth of fat tissue in the female. 相似文献