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11.
Lymphangiomas in children: MR imaging   总被引:9,自引:0,他引:9  
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence.  相似文献   
12.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
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Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age.  相似文献   
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BACKGROUND AND OBJECTIVE: The aim was to examine the immediate effects of short-term anaesthesia on the different components of psychomotor performance of the upper extremity and cognitive functions, and to find out if there were any differences in the sensitivities of the different tests. The measured psychomotor aspects were simple reaction time, choice reaction time, speed of movement, index finger-tapping speed, co-ordination, visual spatial memory capacity, digit-symbol substitution and the Maddox Wing test. METHODS: The subjects were 30 female patients aged 24-50 yr who had been through a minor gynaecological operation. Anaesthesia had been induced with propofol and alfentanil. The measurements were mainly made with the HPM/BEP system, and the tests were performed 1 h before the anaesthesia and immediately after the wake-up. RESULTS: Short-term anaesthesia prolonged the simple reaction time by 7% and the choice reaction times by 25% (one-choice) and 7% (two-choice) and decreased the speed of movement by 10% (one-choice) and 19% (two-choice), index finger-tapping speed by 7% and co-ordination by 7%. In addition, visual spatial memory capacity decreased by 21%, digit-symbol substitution increased by 5% and the Maddox Wing test increased by 68%. CONCLUSIONS: Based on the results, it seems that short-term anaesthesia reduces both signal processing at the central level, and motor control and co-ordination of movements at the peripheral level, and has a decreasing effect on motor performance in the above-mentioned aspects measured immediately after wake-up.  相似文献   
17.
Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%.  相似文献   
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Conflicting data on circannual variation in birth rates of urogenital malformations have been reported previously. To assess risk factors of cryptorchidism we studied the seasonal variation of cryptorchidism in Finland. We performed a prospective cryptorchidism study in Turku, Finland, from 1997 to 2001 to evaluate the incidence of cryptorchidism. Clinical examinations were performed at birth and at 3 months. Of 9511 liveborn boys (1471 preterm boys) 216 (53 preterm boys) were cryptorchid at birth and 106 (19 preterm boys) at 3 months. The incidence of cryptorchidism was significantly higher in spring (February-April) (3.0%) than in summer (May-July) (1.7%) (OR 1.79; 95% CI: 1.23-2.63). This seasonal difference was observed both among preterm and term boys. We conclude that a circannual fluctuation in the incidence of cryptorchidism exists, which indicates an influence by environmental factors. The underlying reason for cyclicity affects similarly both preterm and term boys.  相似文献   
20.
In the course of a health survey covering 561 inhabitants of Tampere, Finland, aged 85 or over, morning urine specimens were studied. 82% of the participants were women. Significant bacteriuria was recorded in 27% of the subjects, 13% of the men and 30% of the women. Pyuria was recorded in 47% of the total material. Replying to the questionnaire, 5% of the subjects reported urinary symptoms and 7% reported to be suffering from urinary tract infection (UTI) diagnosed by a physician. The prevalence of drug-treated UTI was 9% of the subjects replying to the questionnaire. Although positive urinary 'abnormalities' are common in very old people, they do not cause significant distress and do not constitute a disease requiring drug treatment in asymptomatic old people.  相似文献   
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