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71.
72.
OBJECTIVE: To construct nomograms of orbital diameters in early pregnancy by transvaginal sonography. DESIGN: A prospective cross-sectional study. METHODS: The study was performed on 923 consecutive normal singleton pregnancies from 10 to 16 weeks of gestation, using transvaginal high-resolution ultrasound technique. The interocular distance (IOD), binocular distance (BOD), as well as the orbital diameter (OD) at each gestational age (GA, days), were recorded. The distribution of the residuals for the different orbital measurements are also described. RESULTS: The increase in each of the ocular parameters studied could be accurately described by a linear model. The regression equation for orbital measurements as a function of GA was: for IOD, y = 0.153 GA (days) - 6.73 (r2 = 0.82); for BOD, y = 0.387 GA (days) - 16.85 (r2 = 0.80), and for OD, y = 0.132 GA (days) - 6.435 (r2 = 0.79). IOD and OD demonstrate a normal distribution of the residuals with uniform variance. CONCLUSION: The presented data obtained in early pregnancy by transvaginal scan offer normative measurements of the orbital diameter which may be useful in the prenatal diagnosis of congenital syndromes that include, among other manifestations, orbit maldevelopment and growth disturbances.  相似文献   
73.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
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75.
The authors evaluate the results of a series of cases treated by surgery for fractures of the astragalus at the IInd Orthopaedic Division of the University of Pisa between 1978 and 1998. Treatment consisted in reduction and stabilization of the fractures by percutaneous route or by anterolateral approach. Prognosis for fractures of the neck worsens as the Hawkins radiographic classification of degrees increases. Based on the Hawkins clinical evaluation form, excellent and good results were obtained in 56% of cases. Radiographic evaluation confirmed the effectiveness of the Hawkins sign for the prediction of necrosis of the body; this necrosis occurred in 37.5% of cases; arthrosis of the astragalus developed in about half of the patients, which was, however, not always associated with stiffness of this joint. A stiff astragalus was the most fastidious complication, after necrosis of the astragalar body.  相似文献   
76.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
77.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
78.
Doppler and direct measurements of right ventricle to right atrial pressure drop were made during cardiac catheterisation on 28 occasions in 26 infants with congenital heart disease. Age was 10 days to 12 months (median 4.5 months), and weight was 3.1 to 9.0 kg (median 4.7 kg). We measured peak velocity of tricuspid regurgitation by continuous wave Doppler, and the pressure drop was calculated using the modified Bernoulli equation (delta p = 4v2). There was a high correlation (r = 0.95) between direct and Doppler measurements. Doppler values tended to underestimate the right ventricle to right atrial pressure drop, but this was not of clinical significance (mean 2 mm Hg). The 95% confidence interval for the Doppler velocity was -0.41 to +0.26 m/sec, and was consistent across the range of pressures studied. Variability between observers was tested, by two observers performing sequential paired examinations on 16 newborn babies with tricuspid regurgitation. The coefficient of repeatability was 6.3 mm Hg (95% confidence interval 4.7 to 9.5 mm Hg) or 0.26 m/sec (0.18 to 0.50 m/sec). This method of right ventricular pressure estimation, validated previously only in older children and adults, is a reproducible and accurate technique in infants with tricuspid regurgitation.  相似文献   
79.
O'Meara A, Tormey W, Fitz Gerald RJ, Fitzgibbon M, Kenny D. Interpretation of random urinary catecholamines and their metabolites in neuroblastoma. Acta Paediatr 1994;83:88–92. Stockholm. ISSN 0803–5253
This study reports experience in the estimation of urinary catecholamines (uCATs) and their metabolites in the diagnosis and follow-up of neuroblastoma. Random urine samples were assayed for dopamine, noradrenaline and adrenaline, together with their metabolites 4-hydroxy 3-methoxyman-delic acid (HMMA) and homovanillic acid (HVA), using HPLC with electrochemical detection. Twenty of 21 patients had elevation of one or more uCATs metabolites at diagnosis. Patients were monitored serially from diagnosis and, in those patients who had delayed resection of primary tumour (n=13), particular attention was paid to levels at the pre-surgical evaluation as an indicator of persistence of viable disease at the time of surgery; dopamine proved to be the most accurate indicator of persistent disease at this time. Five of these patients developed recurrent disease, 4 of whom had elevation of two or more uCATs metabolites at the time of relapse. Several conclusions can be drawn from this study: (a) results for HMMA, HVA and dopamine in random urine samples will detect all but the most biochemically immature or inert tumours; (b) dopamine may be the most reliable indicator of persistent disease and (c) noradrenaline and adrenaline measurements were of little benefit. As results are Expressed in relation to urinary creatinine, excretion of which may be affected by dietary protein and is therefore not constant, borderline results should be repeated.  相似文献   
80.
A 4 year old girl treated with a standard chemotherapy protocol for acute lymphoblastic leukaemia developed hepatic candidosis during the consolidation phase. This relapsed after a prolonged course of amphotericin B and flucytosine. An eight week course of liposomal amphotericin produced a marked clinical improvement which was sustained for one year. A subsequent relapse was associated with transformation to myelodysplastic leukaemia.  相似文献   
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