RESUMO
The relationships between dromotropic and chronotropic components of five reflexes were studied in rabbits: intravenous and intraarterial blood injections, occlusion of the carotid arteries, Aschner maneuver, and stimulation of depressors. All these stimuli reduced heart rate (except carotid artery occlusion, which induced approximately equal number of tachi- and bradycardic responses). The former three stimuli also reduced atrioventricular (AV) conduction velocity, the changes in these two parameters were proportional. Changes in heart rate induced by Aschner maneuver were more pronounced than changes in AV conduction. Stimulation of depressor induced co-directed shifts in these parameters during the first seconds, but then AV conduction increased, while heart rate remained decreased; bradycardia and AV acceleration persisted for long time after termination of stimulation. Our findings attest to independent regulation of heart rate and AV conduction velocity and to the absence of a strict relationship between these two parameters.
Assuntos
Sistema de Condução Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Reflexo , Animais , Pressão Sanguínea/fisiologia , Estimulação Elétrica , Eletrocardiografia , Hemodinâmica/fisiologia , CoelhosRESUMO
The paper shows the high efficiency and moderate toxicity of inductive treatment in children with Young sarcoma and primitive neuroectodermal tumors by ES-Ipo-97 protocol that includes alternate chemotherapy by the scheme: vincristine, 1.5 mg/m2/day, on days 1, 8, 15; adriamycin, 37.5 mg/m2/day, on days 1 and 2 as 24-hour infusion; cyclophosphanum, 2.1 g/m2/day, on days 1 and 2 (Block A); iphosphamide, 2.4 g/m2/day on days 1 to 5, etoposide, 100 mg/m2/day, on days 1-5 (Block B). It provides evidence for that this therapy is promising and awaits further developments.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Sarcoma de Ewing/tratamento farmacológico , Adolescente , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Vias de Administração de Medicamentos , Esquema de Medicação , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Sarcoma de Ewing/patologia , Índice de Gravidade de DoençaRESUMO
The authors examined 8 patients with pretreated relapsing or resistant solid tumors (Wilms'--4, rhabdomyosarcoma--3, synovial sarcoma--1) who received 16 courses of chemotherapy: iphosphamide, 1800 mg/m2/day (days 1-5), vepeside, 100 mg/m2/day (days 1-5), and carboplatin 500 mg/m2/day (day 1) (IVC) and 18 courses of therapy wherein iphosphamide was replaced by cyclophosphanum, 400 mg/m2/day (days 1-5) (CVC). The patients received 2-4 induction courses (n = 18) and 1-5 consolidation courses (n = 16) with reinfusion of peripheral stem cells (PSC). All PSC separations were performed after the first or second courses of IVC/CVE. There were no significant increases in the duration of leukopenia and thrombocytopenia, in the incidence of infection with a higher ordinal of a course performed by PSC maintenance. The findings suggest that the small doses of PSC stimulated by colony-stimulating factor can maintain hemopoiesis and decrease the rate of the estimated bone marrow depletion long after repeated courses of chemotherapy in patients with prognostically poor solid tumors.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Hipersensibilidade a Drogas/prevenção & controle , Doenças Hematológicas/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Neoplasias Renais/terapia , Neoplasias de Tecidos Moles/terapia , Adolescente , Criança , Pré-Escolar , Hipersensibilidade a Drogas/etiologia , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Estudos Retrospectivos , Rabdomiossarcoma/terapia , Sarcoma Sinovial/terapia , Resultado do Tratamento , Tumor de Wilms/terapiaRESUMO
High-dose thiotepa (800-900 mg/m2) polychemotherapy following combined treatment resulted in high toxicity and lethality. 600 mg/m2 proved optimal for double-conditioning regimens since it exerted antitumor effect without causing fatal complications.