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1.
Barnett  MJ; Zussman  WV 《Radiology》1986,160(1):223-225
Granulocytic sarcoma (chloroma), a rare tumor usually associated with myelogenous leukemia, is capable of invading the meninges or brain parenchyma. Radiologic findings in a case of granulocytic sarcoma of the brain, as well as those in 11 previously reported cases of intracranial leukemic masses, are interpreted. On computed tomographic scans, the lesions can appear isodense or hyperdense, edema and necrosis are variable, and there is uniform enhancement following intravenous administration of contrast material. There may be some affinity for the posterior fossa.  相似文献   
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This study was undertaken to derive an index for predicting coronary events in the first year after a myocardial infarction in "low-risk" patients enrolling in a Cardiac Rehabilitation Program. Data from 145 consecutive patients were analysed. The events were classified as follows: angina requiring further therapy, re-infarction and coronary death. Seventy patients had events: Angina--52, Re-infarction--8, Coronary Death--10. A discriminant function analysis was performed to predict such events using data available at the time of discharge from hospital. The following were significant predictors: (1) previous infarction/angina, (2) radiological evidence of cardiomegaly or lung congestion in the Coronary Care Unit, (3) Non-Q wave infarction and (4, 5 and 6) angina, atrial arrhythmias and a decrease in R wave amplitude in V5 during a pre-discharge exercise test. The jack-knife method classified correctly 71.2% of those with events and 72.6% of those without events. In patients with discriminant scores greater than +0.2, 82% developed events.  相似文献   
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Endothelium-dependent relaxation in experimental atherosclerosis in the rabbit   总被引:11,自引:0,他引:11  
The effect of feeding a diet supplemented with lipids and containing 2% cholesterol on the endothelium-dependent relaxation of rabbit aorta to acetylcholine was assessed. The effect of feeding a standard rabbit diet after an initial period of 2% cholesterol feeding was assessed also. Age-matched male, New Zealand white rabbits were fed either a 2% cholesterol diet or a standard rabbit diet. The animals were anesthetized with pentobarbitone sodium (25 mg/kg) and killed either at the beginning of the study (0 weeks) or at 4, 8, or 10 weeks. The animals in the reversal study were fed the 2% cholesterol diet for 6 weeks and killed after an additional 14 and 32 weeks on standard diet. The extent of atherosclerosis in the aorta was assessed by Sudan Red staining, estimation of tissue cholesterol, and light and electron microscopy. The relaxation response to acetylcholine was measured in rings of the thoracic aorta following precontraction with norepinephrine (-6.0 log mol/l). The relaxation was significantly impaired in aortas from rabbits fed the 2% cholesterol diet compared to aortas from animals fed the standard diet. The impairment of relaxation was apparent as early as 4 weeks after the start of the 2% cholesterol diet and remained impaired over the next 6 weeks. No improvement in endothelium-dependent relaxation was seen in rabbits on the reversal diet for 14 and 32 weeks. Thus, endothelium-dependent relaxation is attenuated in animals fed a 2% cholesterol diet, and the loss of relaxation persists for at least 32 weeks after the animals are returned to a standard diet.  相似文献   
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Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school‐age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole‐body and hip scans were measured using the same densitometer (GE‐Lunar iDXA) at a mean age of 6.2 years. Hip dual‐energy X‐ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole‐body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre‐ and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American Society for Bone and Mineral Research.  相似文献   
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Background: Cardiac opioid peptides have been identified to exert important adaptive metabolic signalling for cardioprotection against ischaemia or hypoxia‐related injury. Aims: To determine myocardial methionine‐enkephalin content in children with hypoxemic congenital heart defects and to correlate myocardial content of methionine‐enkephalin with the extent of arterial oxygen desaturation. Methods: Children (n= 20, median age of 16 months), undergoing cardiac surgical repair (tetralogy of Fallot, 17/20), were included in this study. Arterial oxygen saturation was measured on admission. Myocardial samples obtained during surgery were assayed via radioimmunochemistry for methionine‐enkephalin content. Results: Greater methionine‐enkephalin content was measured in the right ventricles of the patients suffering from recent cyanotic spells compared with those with no recent spells (cyanotic spells: 2418 ± 844 pg/g wet weight tissue, n= 6; no spells: 1175 ± 189 pg/g wet weight tissue, n= 14, P= 0.04). An inverse correlation was evident between the arterial oxygen saturation and myocardial methionine‐enkephalin content. Conclusion: Myocardial methionine‐enkephalin levels increase with the severity of hypoxic stress in congenital cardiac disease and may play an important adaptive role in countering adrenergic over‐activity and related excess demand on myocardial metabolic capacity.  相似文献   
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An investigation into the incidence and other features of dry socket in Sri Lanka was considered worthwhile as working conditions, general health of patients and related factors may be different in developing countries. The present study was conducted at two institutes which provide differing facilities and conditions. The overall incidence was found to be 3.5% which is similar to figures reported in the U.K. and Europe. The pattern of dry socket as seen at the two institutes regarding delayed onset, lower molar site specificity, female predominance and relation to difficulty of extraction was similar to each other and to those described in previous studies. These findings support a multifactorial aetiology as does a review of the recent literature.  相似文献   
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【目的】 探讨儿童牙龈炎与恒牙龋的相关关系,为儿童牙龈炎防治工作提供理论依据。 【方法】 采用多阶段分层整群随机抽样的方法共调查广州市12~13岁儿童1 115人。检查方法和标准参考1997年WHO推荐的《口腔健康调查基本方法》,牙龈炎检查六颗指数牙,龋病检查全口恒牙,分别采用牙龈指数(GI)和DMFT记录检查结果。Logistic回归分析儿童牙龈炎与恒牙龋病的关系。 【结果】 广州市12~13岁儿童牙龈炎患病率72.65%,中、重度牙龈炎患病率分别为28.16%和5.83%。恒牙龋患病率为25.83%,其中未充填龋占龋齿的73.73%。Logistic回归分析显示未充填龋是广州市12~13岁儿童牙龈炎患病的危险因素。 【结论】 广州市12~13岁儿童牙龈炎患病率较高,有未充填龋存在的儿童是广州市儿童牙龈炎重点防治人群。  相似文献   
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