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We recently diagnosed subcutaneous fat necrosis in a newborn female infant using fine needle aspiration cytology. The neonate had perinatal asphyxia and her mother a difficult labor, but otherwise the neonate was well developed and healthy and within a few days developed well-defined areas of subcutaneous induration all over. On cytologic examination of the aspirated material, many necrotizing fat cells were found with refractile, needle-shaped crystals arranged in a sheaflike or starburst pattern. Subcutaneous fat necrosis of the newborn is uncommon today, and although the histologic findings from excised tissue are known, this appears to be the first case in which the diagnosis was possible from a sample of fine needle aspirate. 相似文献
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radon and radon daughter concentrations have been measured in 33 “energy-efficient” homes in a small subdivision in Kanata, Ontario. Integrated radon measurements were determined over three month periods for a year using solid state nuclear track detectors. Radon and radon daughter grab sample determinations were made during corresponding periods and confirm the distributions of the integrated radon measurements.Annual average individual home radon concentrations show an 8 fold concentration range between homes. This variability in radon concentrations is not reflected in the range of air exchange rates for the homes. A distinct seasonal variation is noted for the median values of the radon and radon daughter concentrations and the equilibrium factor F in the dwellings. 相似文献
24.
OBJECTIVES: Our purpose was to determine those factors affecting the route of delivery decisions and the effect of delivery route on maternal and newborn outcomes with the macrosomic fetus. Do higher cesarean rates result in improved newborn outcomes? STUDY DESIGN: A 10-year (1985 to 1994) retrospective data set was used to analyze patients with newborns weighing > or = 4536 and 4000 to 4535 gm at two Green Bay hospitals. Patients with newborns weighing 2500 to 3999 gm were similarly analyzed for comparison purposes. Individual and obstetrician group cesarean rates and newborn and maternal outcomes were identified. RESULTS: Cesarean birth rates for the fetus weighing > 4000 gm were low and varied from 12.8% in the low obstetrician cesarean rate group to 24.0% in the high group. Higher obstetrician group cesarean rates did not result in improved newborn outcomes. Newborn morbidity and mortality were very low but significantly higher for cesarean birth newborns. Maternal complications were fairly low with cesarean birth and rare after vaginal delivery. CONCLUSION: Patients with a suspected macrosomic fetus should be given the same opportunity to achieve a vaginal delivery as patients with smaller fetuses. 相似文献
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RK Batra JC Olsen DK Hoganson B Caterson RC Boucher 《Canadian Metallurgical Quarterly》1997,272(18):11736-11743
Gene therapy may be an important adjuvant for treating cancer in the pleural space. The initial results of retroviral gene transfer to cancer cells in malignant pleural effusions revealed that transduction was markedly inhibited, and studies to characterize the inhibitory factor(s) were performed. The inhibition was contained within the soluble, rather than cellular, components of the effusions and was demonstrated with amphotropic, gibbon ape leukemia virus, and vesicular stomatitis virus-glycoprotein pseudotyped retroviral vectors. After excluding complement proteins, a series of studies identified chondroitin sulfates (CSs) as the inhibitory substances. First, treatment of the effusions with mammalian hyaluronidase or chondroitinases, but not Streptomyces hyaluronidase, abolished the inhibitory activity. Second, addition of exogenous CS glycosaminoglycans mimicked the inhibition observed with pleural effusions. Third, immunoassays and biochemical analyses of malignant pleural effusion specimens revealed CS in relevant concentrations within pleural fluid. Fourth, proteoglycans/glycosaminoglycans isolated from the effusions inhibited retroviral gene transfer. Analyses of the mechanism of inhibition indicate that the chondroitin sulfates interact with vector in solution rather than at the target cell surface. These results suggest that drainage of the malignant pleural effusion, and perhaps enzymatic pretreatment of the pleural cavity, will be necessary for efficient retroviral vector mediated gene delivery to pleural metastases. 相似文献
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STUDY DESIGN: The study of two patients whose rib deformity was treated using a new endoscopic thoracoplasty technique is reported. OBJECTIVES: To report a new endoscopic thoracoplasty technique for the treatment of rib deformities associated with idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Thoracoplasty has traditionally been performed as an open procedure, often necessitating additional incisions and/or tissue dissection. METHODS: Two children with significant rib humps associated with idiopathic scoliosis were treated with a new endoscopic thoracoplasty technique. RESULTS: Both children showed dramatic cosmetic improvement of their rib deformity. CONCLUSIONS: The indications for the use of video-assisted thoracoscopic surgery in the treatment of pediatric spinal deformity are expanding. We have extended our video-assisted thoracoscopic surgery repertoire to include endoscopic thoracoplasty for treatment of rib deformities associated with idiopathic scoliosis. The technique for endoscopic thoracoplasty is discussed, and illustrative cases are presented. 相似文献
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RK Manoff 《Canadian Metallurgical Quarterly》1997,57(3):260-265
The possible contamination of groundwater by the insecticide carbofuran was assessed with the behavior assessment model (BAM) and groundwater pollution-potential model (GWP). Dissipation coefficients of this insecticide in two subtropical soils at different moisture contents and soil temperatures were studied by determining the degradation and adsorption of the herbicide in soils. Movement of carbofuran was studied by leaching the insecticide in a soil column in the laboratory. Under 40% field capacity and at 25 degrees C, more than 80% of carbofuran residue was found in both Luchu clay and Yuanlin silty clay loam after incubation for 63 days. The results indicate that the higher the moisture content in the soil, the less the carbofuran residue under the soil moisture below the field capacity. Carbofuran tends to dissipate more easily in Yuanlin soil than in Luchu soil. The distribution coefficient (Kd) with r2 of 0.69 and 0.92 for Luchu and Yuanlin soils, respectively, was found using the first-order kinetics law. In leaching experiment, carbofuran exhibited easier movement in Luchu than in Yuanlin soil. 相似文献
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