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L C Jameson C A Smith J A Dempsey 《Journal of applied physiology (Bethesda, Md. : 1985)》1983,55(5):1623-1629
We developed a method to produce stable alterations in the ionic composition of the medullary chemoreceptor environment. A double-lumen catheter system (Hustead epidural needle and epidural catheter) was placed through a plastic cisternal guide tube into the cisterna magna of awake goats. A push-pull perfusion system using a modified infusion pump delivered matched cerebrospinal fluid (CSF) perfusate inflow and outflow of 3.1 ml/min. Ventilation changed within 15 min of the initiation of perfusion and reached steady state within 45-65 min. Steady-state ventilatory responses could be maintained for up to 240 min and were readily reversed in response to a change in [HCO-3]. Perfusions with normal mock CSF ( [HCO-3] = 23 meq/l) caused no change from nonperfused values. Over the range of CSF perfusate [HCO-3] used (13.5-34.4 meq/l), the gain of the steady-state ventilatory response averaged 0.6 Torr X meq-1 X l. [3H]inulin and [HCO-3] were equal in inflow and outflow by 20-30 min of perfusion indicating complete mixing of bulk CSF in the cistern. Anatomic study after methylene blue dye perfusion showed dye distribution to subarachnoid spaces of midbrain, cervical cord, cerebellum, medulla, and most of the cortex but not to any ventricles. This perfusion technique produces prolonged, stable, reproducible, and repeatable changes in the medullary chemoreceptor ionic environment of awake goats, is relatively atraumatic, and permits high flow through the cisternal subarachnoid space. 相似文献
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R Hast L Engstedt S Jameson A Killander B Lundh P Reizenstein K O Sk?rberg A M Udén B Wadman 《Blut》1978,37(1):19-26
In order to study the effect of oxymetholone therapy in advanced myelofibrosis, 11 patients (4 females, 7 males) were given, 3--5 mg per kg body weight, long-term oxymetholone treatment in a prospective multicenter study. Five cases had previously had a diagnosis of polycythemia vera. All patients had anemia initially, 4 leukocytopenia and 10 thrombocytopenia in addition. Hepato-splenomegaly was present in all cases but in varying degree. Five patients required regular blood transfusions before treatment. In 9 of the 15 courses given, there was normalization of the peripheral blood or substantial improvement (better than 3 g hemoglobin/dl or 50 X 10(9) platelets/1) after androgens. Significant effects were noted both on hemoglobin values and platelet counts. The need for blood transfusions ceased completely in all 5 cases. When oxymetholone treatment was reduced or interrupted 4 patients relapsed; 2 of them responded to a renewed course. The red cell counts returned to previous polycythemic values in one patient and another died from acute leukemia. The results of this study suggest that androgens might be of value in advanced cases of myelofibrosis with transfusion-requiring anemia or severe thrombocytopenia. 相似文献