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21.
Infarcts of the corpus callosum have not been well documented in the radiologic literature. We present five cases that were unusual in either their clinical or radiologic presentation or both. Biopsies were performed in three of the five cases, and in time, all lesions evolved in a pattern consistent with infarct. Recognition of the varied clinical and radiologic presentation of infarcts of the corpus callosum will obviate the need for biopsy in most patients.  相似文献   
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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   
24.
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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BACKGROUND AND PURPOSE: Discrimination between enhancing mass lesions in acquired immunodeficiency syndrome (AIDS) patients with conventional CT and MR imaging remains difficult. We determined the effect of lesion size on thallium-201 brain single-photon emission tomography (SPECT) imaging in differentiating primary brain lymphoma from cerebral toxoplasmosis. METHODS: We retrospectively identified 35 AIDS patients with a total of 48 focal enhancing mass lesions on contrast-enhanced brain CT and/or MR images who subsequently underwent thallium-201 brain SPECT imaging. The thallium index of each lesion was evaluated on the basis of the ratio of mean uptake in the lesion compared with the corresponding contralateral side. Receiver operator curves were drawn to determine the optimal thallium index threshold. The effect of lesion size on scan accuracy was evaluated. RESULTS: Malignant lesions in 20 patients had a mean thallium index of 2.4 (range, 1-11). Infectious lesions in 15 patients had a mean thallium index of 1.6 (range, 1-3.6). Twenty-five lesions were <2 cm (14 malignant, 11 nonmalignant) and 23 lesions were > or =2 cm (14 malignant, 9 nonmalignant). Thallium index was not a significant predictor of malignancy in the lesions <2 cm by using the logistic regression (P = .27). Receiver operator curve analysis by using thallium index of 2 in small lesions yielded 50% sensitivity and 82% specificity. In contrast, thallium index was a significant predictor of malignancy in lesions > or =2 cm (P < .01), yielding 100% sensitivity and 89% specificity. CONCLUSION: Lesion size is a significant determinant of the accuracy of thallium-201 brain SPECT imaging, which should be the initial diagnostic tool for lesions > or =2 cm.  相似文献   
27.
Background The timing of aggressive airway intervention in adult epiglottitis is controversial. Aims To correlate Friedman’s staging of epiglottitis on admission with the airway interventions undertaken. Methods A retrospective study of 23 adult patients, mean age 51 years (range 29–81 years), who had been admitted with acute supraglottitis between March 1988 and December 2000 was undertaken. Results Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous therapy. Conclusions Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should probably be lowered to those patients with rapid-onset stage III (moderate respiratory distress, stridor, respiratory rate >30 per minute, pCO2 >45mmHg) disease.  相似文献   
28.
The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives.  相似文献   
29.
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131).  相似文献   
30.
Gastroduodenoscopy and retrograde cholangiopancreatography has been performed on 25 occasions in 20 children aged between 7 and 16. Radiographs of the clinically relevant duct or ducts were achieved in 96% of attempts, with no complications. The diagnostic information proved useful clinically; in particular it provided a precise map if biliary or pancreatic surgery was being contemplated. Several unexpected congenital duct anomalies were found. This and other recent reports, particularly from Germany, indicate that endoscopic retrograde cholangiopancreatography deserves greater application in children, and can also be used in babies.  相似文献   
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