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苗慧  肖文彬  秦伯益 《药学学报》1990,25(9):646-651
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dtmax,Vmax,Vpm和LVSP,延长T-dp/dtmax,减慢心率。MHDF还能舒张大鼠胸主动脉,ED50为6.5×10-6mol/L;非竞争拮抗NA和CaCl2致主脉收缩,pD2′为3.11±0.21和3.73±0.07;抑制高K+致主动脉收缩,IC50为1.76×10-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。  相似文献   
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Metabolic disorders during hepatic transplantation can be partly induced by blood transfusion. A retrospective survey of perioperative biological data recorded in patients under 18 years of age having liver transplantation was performed. Blood transfusion was also studied. For this evaluation, patients were divided in a paediatric group I (n = 20; mean age: 3.7 years) and an adolescent group II (n = 11; mean age: 14.3 years). Blood transfusion was significantly (p less than 0.05) more important in group I (302 +/- 286 ml X kg-1) than in group II (148.5 +/- 156 ml X kg-1). Autotransfusion of washed red cells was performed in six patients, allowing a mean 17 +/- 7% saving in blood transfusion. Severe hypernatraemia over 152 mmol X l-1 due to blood transfusion was observed only in five patients in group I. Hyperglycaemia increasing till the revascularization of the new liver was constant in both groups, but significantly more pronounced in group II. Cardiac arrest occurred twice in group I at initial revascularization. In group I, children with biliary atresia were not significantly different from the others for the duration of operation and the volume of blood transfusion; however the latter was more abundant. Conversely, in group II, the duration of operation was longer (p less than 0.05) in patients with previous abdominal surgery than in others. Finally the paediatric group differs from the adolescent group by obvious differences in anaesthesia and intensive care and specifically in hepatic transplantation by larger volume of blood transfusion leading to severe hypernatraemia. In further studies, adolescents should be distinct from the paediatric group and included in the adult group.  相似文献   
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BACKGROUND: The effects on morbidity were examined of providing an educational intervention and a written guided self-management plan to the parents of pre-school children following a recent attendance at hospital for asthma or wheeze. METHODS: A prospective, randomised, partially blinded, controlled trial was designed at two secondary care centres. Over a 13 month period 200 children aged 18 months to 5 years at the time of admission to a children's ward or attendance at an accident and emergency department or children's (emergency) assessment unit (A&E/CAU) with a primary diagnosis of acute severe asthma or wheezing were recruited. 101 children were randomised into the control group and received usual care and 99 were assigned to the intervention group and received: (1) a pre-school asthma booklet; (2) a written guided self-management plan; and (3) two 20 minute structured educational sessions between a specialist respiratory nurse and the parent(s) and child. Subjects were assessed at 3, 6, and 12 months. The main outcomes were GP consultation rates, hospital re-admissions, and attendances at A&E/CAU. Secondary outcomes included disability score, caregivers' quality of life, and parental knowledge of asthma. RESULTS: There were no statistically significant differences between the two groups during the 12 month follow up period for any of the main or secondary outcome measures. CONCLUSIONS: These results do not support the hypothesis that the introduction of an educational package and a written guided self-management plan to the parents of pre-school children with asthma who had recently attended hospital for troublesome asthma or wheeze reduces morbidity over the subsequent 12 months.  相似文献   
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