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991.
Activating effect of substance P on nerve tissue in culture   总被引:1,自引:0,他引:1  
The effect of substance P on organotypic culture of rat sympathetic ganglia and spinal cord was studied. Substance P was able to stimulate the fibre outgrowth from explant, to increase the numbers of glial and fibroblasttypic cells in ganglia growth zone. The effect was observed in the range from 10(-5) to 10(-12) M (for sympathetic ganglia) and from 10(-5) to 10(-14) M (for spinal cord culture). It is suggested that substance P can be used as a nonspecific growth factor for peripheral and central nervous tissue.  相似文献   
992.
Accidental transmission of Chagas disease to man by blood transfusion is a serious problem in Latin America. This paper describes the testing of several naphthoquinones, some of which were active against blood trypomastigotes in vitro at 4 degrees C and might therefore warrant further study for preventing transmission of Chagas disease by blood transfusion.  相似文献   
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The neuronal morphological development of the avian telencephalic cortex (DMC) is studied in Golgi-stained brain sections. The neuronal types at embryonic days 10, 13, 16, as well as of newborn chick are identified. The immature neurons are characterized by the presence of hair-like processes, growth cones and dendritic varicosities. These characteristics are absent in neuronal types of newborn chick. There are five patterns of differentiation, which produce six neuronal types in the newborn chick: horizontal neurons, pyramidal neurons, bipyramidal neurons, short axon multipolar neurons, long axon multipolar neurons and periventricular neurons. The morphological features of migrating embryonic cells are described. The dendritic spines appear in 16-day embryos in the majority of neuronal types.  相似文献   
998.
Pulmonary atresia with intact ventricular septum   总被引:1,自引:0,他引:1  
Neonates with pulmonary atresia with intact ventricular septum are ductus dependent from birth. The initial approach in these patients is to ensure continued adequate pulmonary blood flow in anticipation of imminent spontaneous closure of the ductus. Our experience and evolving approach in the management of 16 consecutive neonates with pulmonary atresia with intact ventricular septum from 1978 to 1984 is presented. On the basis of the revised classification by Bull and associates, we divided the patients into four different groups according to right ventricular morphology. Basically, three types of palliative surgical procedures were performed: systemic-pulmonary artery shunt; systemic-pulmonary artery shunt with pulmonary valvotomy; and pulmonary valvotomy alone. Systemic-pulmonary artery shunt is the most important part of neonatal palliation. Our present routine is to perform left subclavian-main pulmonary artery shunt with a polytetrafluoroethylene tube in all patients and, in addition, to perform an open transpulmonary valvotomy without cardiopulmonary bypass in patients with a patent infundibular portion of the right ventricle. Our technique and the advantages of this type of shunt procedure are discussed. Patients with right ventricular sinusoidal-coronary artery communications are a subgroup with an additional problem. In our series, patients with this anomaly are categorized into groups with major and minor connections and their surgical significance is discussed. Overall, there was one death among 16 patients after neonatal palliative procedures and one death among five patients after hemodynamic repair.  相似文献   
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