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1.
Cerebral infarction is rare in premature newborns and is most commonly the result of arterial embolization from the placenta. A focal echodense area was identified on prenatal cranial ultrasonography (US) in a premature infant (34 weeks of gestation). After birth, cerebral infarction was confirmed by magnetic resonance imaging (MRI). The clinical findings, imaging findings and pathogenesis are discussed. New diagnostic methods such as MRI show to be a useful approach in the neonatal period facilitating recognition of cerebrovascular accidents also in low-birth-weight infants.  相似文献   
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BACKGROUND: Chronic kidney disease patients who are resistant to erythropoietin (EPO) treatment may suffer from malnutrition and/or inflammation. METHODS: In a cross-sectional study of haemodialysis patients, we investigated the relationship between the natural logarithm of the weekly EPO dose normalized for post-dialysis body weight and outcome measures of nutrition and/or inflammation [BMI, albumin and C reactive protein (CRP)] by means of multiple linear regression analysis. On the basis of the decile distribution of weekly EPO doses, we also evaluated four groups of patients: untreated, hyper-responders, normo-responders and hypo-responders. RESULTS: Six hundred and seventy-seven adult haemodialysis patients were recruited from five Italian centres. BMI and albumin were lower in the hypo-responders than in the other groups (21.3+/-3.8 vs 24.4+/-4.7 kg/m(2), P<0.001; and 3.8+/-0.6 vs 4.1+/-0.4 g/dl, P<0.001), whereas the median CRP level was higher (1.9 vs 0.8 mg/dl, P = 0.004). The median weekly EPO dose ranged from 30 IU/kg/week in the hyper-responsive group to 263 IU/kg/week in the hypo-responsive group. Transferrin saturation linearly decreased from the hyper- to hypo-responsive group (37+/-15 to 25+/-10%, P = 0.003), without any differences in transferrin levels. Ferritin levels were lower in the hypo-responsive than in the other patients (median 318 vs 445 ng/ml, P = 0.01). At multiple linear regression analysis, haemoglobin, BMI, albumin, CRP and serum iron levels were independently associated with the natural logarithm of the weekly EPO dose (R(2) = 0.22). CONCLUSIONS: Our findings support a clear association between EPO responsiveness and nutritional and inflammation variables in haemodialysis patients; iron deficiency is still a major cause of hypo-responsiveness.  相似文献   
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Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
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人体液中喷布洛尔及其代谢物的GC/MS分析   总被引:1,自引:0,他引:1  
用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。  相似文献   
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BACKGROUND AND OBJECTIVE: The complications of 25-gauge transconjunctival sutureless vitrectomy based on the surgical indications were reviewed. PATIENTS AND METHODS: Thirty-eight patients underwent 25-gauge transconjunctival sutureless vitrectomy. Indications for vitrectomy, preoperative and postoperative best-corrected visual acuity, preoperative and postoperative intraocular pressure, and any intraoperative or postoperative complications were recorded. RESULTS: Complications included the need to suture a leaking sclerotomy intraoperatively in four eyes (9%), all of which involved oil removal; postoperative hypotony with choroidals in two eyes (5%); mild progression of nuclear sclerotic cataract in one eye (2% of all eyes, 4% of phakic eyes); the need to switch to 20-gauge pars plana vitrectomy in one eye (2%); corneal abrasion in one eye (2%); and retinal detachment in one eye (2%). Sclerotomy leakage and hyopotony with choroidals were only encountered in cases involving previously vitrectomized eyes, whereas none of the eyes without previous vitrectomy had leakage-related complications. CONCLUSIONS: Previously vitrectomized eyes have a higher incidence of complications related to postoperative leakage, possibly due to the lack of plugging effect of peripheral vitreous on the unsutured sclerotomy. One should consider suturing any leaking sclerotomy at the conclusion of surgery involving previously vitrectomized eyes.  相似文献   
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The concept of central shunting in smaller children with the Waterston shunt was initially well accepted. It has been abandoned because of the difficult estimation of lumen size, preferential flow to the right side, and difficulty in the take-down of the shunt. We have replaced the Waterston shunt with a short segment of polytetrafluoroethylene between the ascending aorta and the main pulmonary artery. From January 1979 to December 1986, 190 shunt operations were performed in 157 patients, with the use of 26 classic Blalock-Taussig shunts (13.7%), six Waterston shunts (3.1%), nine Glenn shunts (4.7%), 80 central aortopulmonary polytetrafluoroethylene shunts (42.2%), and 69 modified Blalock-Taussig shunts (36.3%). Polytetrafluoroethylene grafts were used for 149 of the 190 (78.4%) shunts. Overall mortality was 15.2%, with nine early deaths (4.7%) and 20 late deaths (10.5%). Deaths were due to the complex nature of the congenital anomaly or definitive surgical repair. The patients weighed from 1.6 to 48 kg and ages ranged from 1 day to 22 years. We have modified our technique so that (1) graft length is less than 0.5 cm and both ends are beveled, (2) the aortotomy is fashioned with a punch, (3) the center of the polytetrafluoroethylene graft is never clamped, (4) heparin is given during the construction of the shunt, and (5) aspirin (10 mg/kg/day) is administered daily. Patency ranges from 1 to 4 years. We conclude that the polytetrafluoroethylene shunt provides excellent palliation and that the central shunt, in the smaller child and infant, offers the benefits of shunting without distortion of the peripheral pulmonary arteries.  相似文献   
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