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131.
Clinical and hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery 总被引:1,自引:0,他引:1
H Bolooki W Williams RJ Thurer A Vargas GA Kaiser F Mack AR Ghahramani 《Canadian Metallurgical Quarterly》1976,72(5):756-768
In order to establish criteria for elective use of the intra-aortic balloon pump (IABP) in patients having cardiac surgery, we conducted a retrospective study of 43 patients who required counterpulsation, because of inability to be weaned from cardiopulmonary bypass, between May, 1972, and June, 1974. Patients in cardiogenic shock preoperatively were excluded. The 43 patients included 23 (Group A) who had severe preoperative left ventricular dysfunction with a mean cardiac index less than 1.8 L. per minute per square meter, ejection fraction less than 30 per cent, and end-diastolic pressure greater than 22 mm. Hg; 20 patients (Group B) had a combination of moderate cardiac dysfunction (cardiac index less than 2.2, ejection fraction less than 40, end-diastolic pressure less than 18) in the presence of acute infarction or severe aortic stenosis (gradient greater than 80 mm. Hg) with or without coronary disease. An inverse relationship was noted between survival and delay from completion of operation to the use of 1ABP. Thirty-two of 43 patients were weaned off bypass and were balloon assisted for 12 to 96 hours postoperatively; 25 patients were discharged (58 per cent). In Subgroup A, 14 of 23 (60 per cent) and, in Subgroup B, 9 of 20 (45 per cent) were long-term survivors. Based on these findings, 45 patients were operated upon between June, 1974, and December, 1975, with elective use of 1ABP and were assessed by serial hemodynamic studies. Sixteen had severe preoperative left ventricular dysfunction similar to Subgroup A and 29 had moderate dysfunction in combination with pathology similar to Subgroup B. Fifteen of these patients were hemodynamically unstable at time of arrival in the operating room; 1ABP was inserted under local anesthesia. Thirty-nine patients (87 per cent) were weaned off bypass and were hospital survivors. In Subgroup A, 13 of 16 (81 per cent) and, in Group B, 21 of 29 (72 per cent) were long-term survivors. Criteria for elective use of 1ABP in cardiac surgery should include severe preoperative left ventricular dysfunction or a combination of moderate dysfunction with coronary or valvular pathology. Elective 1ABP improves the survival with trivial iatrogenic morbidity. 相似文献
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Ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered in a dose of 20 mg/kg/d to 21 patients with symptomatic Paget's disease. All patients were treated for 6 months and then followed for an additional 6 months. There was a striking decline in serum alkaline phosphatase and urinary hydroxy-proline excretion observed after 3 months of therapy which was not significantly improved in the succeeding 3 months. Concomitantly there was marked improvement in clinical symptoms and bone scans. Following cessation of therapy, continued biochemical and clinical evidence of remission persisted. Several patients on repeat treatment with EHDP appeared to respond promptly. Side effects were minimal except for a possibly related osteomalacia and increased incidence of pathologic fractures. 相似文献
134.
The effects of total (T-NSB) and subtotal (S-NSB) destruction of the nigrostriatal bundle were compared with the effects of large lateral hypothalamic (LH) lesions on various aspects of the lateral hypothalamic syndrome. The T-NSB and LH lesions produced equivalent decreases in caudate and telencephalic contents of dopamine and norepinephrine, while with the exception of telencephalic dopamine, S-NSB lesions had consistently smaller effect. The T-NSB and LH lesions produced equivalent effects on duration of aphagia and adipsia (Stages 1 to 3) and on long-term decreases in body weight and ad lib water consumption, and these effects were always greater than those produced by the S-NSB lesion. These aspects of the lateral hypothalamic syndrome appeared to be related to the interruption of the nigrostriatal bundle and consequent decrease in caudate dopamine. The T-NSB and S-NSB lesions produced equivalent long-term deficits in water regulation as measured by drinking in the absence of food or in response to intra- and extracellular dehydration, but these deficits were always significantly less than those produced by the LH lesion. It was concluded that these regulatory deficits were not related to destruction of catecholamine pathways. All three lesions totally blocked eating in response to a glucoprivic challenge. This aspect of the lateral hypothalamic syndrome, therefore, results from destruction of a small portion of the lateral diencephalon and may be related to the interruption of the dopaminergic mesolimbic system. 相似文献
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GA Ulett 《Canadian Metallurgical Quarterly》1983,76(4):421-423
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对硫酸庆大霉素/α半水硫酸钙载药体系进行了模拟条件下体外释药研究,并对其晶体结构进行了分析。X-射线衍射分析结果表明,载药体系中一定含量的硫酸庆大霉素不会影响α半水硫酸钙的水化;模拟条件下体外释药研究表明,各种药物含量的载药体系均表现出了良好的缓释性能,持续释放时间超过了360h;随着试样中载药量的增加,其药物释放速率加快;另外,构制了均一分散和核壳结构两种载药体系,研究结果表明,均一分散型在前期释放速度要大于核壳结构型,而后期核壳结构型则比均一分散型要高。 相似文献
140.
根据基底表面客观存在杂相(不同材料、或同一材料的不同晶面等)的实验事实,考虑到粒子进出不同的相界具有不同的能耗,粒子在不同相基底上扩散具有不同的能耗,建立了非均质基底上扩散能量有限的多中心成核的DLA模型,对非均质基底上团簇的生长过程进行了Monte Carlo模拟。模拟结果表明:沉积在此类基底表面的粒子凝聚成具有分形结构的团簇的数目、团簇的回旋半径、团簇的分形维数均呈现一种周期性的变化。 相似文献