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The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
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Percutaneous transluminal coronary angioplasty (PTCA) of heavily calcified rigid coronary arteries has decreased success and increased complication rates. Three cases are presented describing a new technique for the dilatation of severely calcified coronary arteries that were not dilatable by conventional angioplasty methods. This technique involves the use of a balloon dilatation catheter system parallel to a guide wire. © 1993 Wiley-Liss, Inc.  相似文献   
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Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.  相似文献   
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Medical records of 158 patients with bipolar depression were analysed for the incidence of a switch from depression to maniform states (mania and hypomania). Relation to psychopharmacological treatment was investigated. Thirty-nine (25%) patients of the total sample had switched to a maniform state during the treatment period in the hospital. Among that group the phenomenon occurred in 23 patients (15%) as a hypomania and in 16 patients (10%) as a mania. Patients with a switch were significantly more often treated with tricyclic antidepressants (TCA) than patients without switch (79.5% vs 51.3%). Mood stabilising medication might reduce the risk for switching, especially in patients treated with TCA; however, it seems not totally sufficient, since 59% of the switched patients received mood stabilisers. The switch phenomenon was not associated with sociodemographic or clinical data. Received: 23 September 1998 / Accepted: 28 September 1998  相似文献   
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The number of aeromedical transport services accepting pediatric patients (ATSP) in the United States has increased greatly over the past decade. Most aeromedical transport services are primarily designed for adults but will also transport children. Suggested guidelines for ATSP were published by the American Academy of Pediatrics (AAP) in 1986. This survey of 65 ATSP and their abidance by the major AAP guidelines showed that two thirds of the ATSP were based at facilities with pediatric tertiary care capabilities; most ATSP were not directed by pediatric critical care (PCC) or pediatric emergency care (PEC) specialists; most transport team personnel were not trained in PCC or PEC; most ATSP had specific protocols for different clinical situations; most ATSP had separate equipment appropriate for pediatric patients; and there was little variation in transport team composition based on different clinical situations. In summary, all ATS surveyed transported children, but few were aware of the AAP guidelines, and only one in 65 was in complete abidance with the recommendations.  相似文献   
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