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51.
52.
There are few reports which discussed normal RI-cisternography in infancy and childhood. The cisternograms of the children between 2 months and 13 year-old were classified under a criteria into three groups; 17 normal cases, 135 borderline cases and 77 abnormal cases. The former two groups were compared with each other and characteristic findings of RI-cisternography in infants and children were appreciated clinically. And we attempted to establish normal RI-cisternography. The characteristic findings are: 1) When the images of cisterna magna is dilated, it can not be concluded directly that the abnormality of posterior fossa are suspected. 2) The bulk flow of CSF in infancy and childhood flows faster in intracranial subarachnoid space as well as intraspinal than the flow of adults. 3) Early ventricular reflux seems to be not valuable clinically. But we would like to emphasize that the incidence of these findings are variable as children grow older. The mechanism of this phenomenon needs further investigation. 相似文献
53.
SD Greenberg GA Hurst SC Christianson WJ Matlage IG Hurst LC Mabry 《Canadian Metallurgical Quarterly》1976,66(5):815-822
Five hundred fifty-four workers, 84% of whom are chronic cigarette smokers, have been examined during the past year with emphasis on the role of sputum cytopathology in the early detection and diagnosis of lung cancer. Of the 554, 232 (42%) have shown squamous metaplasia, 44 (8%), mild to moderate atypias, 18 (3.2%), severe atypias, and two (0.4%), squamous carcinoma. Both of the carcinomas were in x-ray negative, cytopathology-positive elderly cigarette smokers. Ferruginous bodies have been found in the sputa of 187 (33%) workers. Ferruginous bodies in the sputum do not appear to be a marker for severe atypias; rather, their presence correlates best with duration and extent of industrial exposure to asbestos. 相似文献
54.
Rabbits received intravitreal injections of gentamicin and indirect ophthalmoscopy, electroretinography, and histopathology determined relative toxicity. An intravitreal dose of 0.1 to 0.2 mg of commercially available gentamicin was well tolerated in the rabbit eye. A dosage of 0.4 mg or higher consistently produced significant ocular toxicity as evidenced by extinction of the electroretinogram, gross fundus changes, and histopathologic alterations. 相似文献
55.
R Levenson IG Macara RL Smith L Cantley D Housman 《Canadian Metallurgical Quarterly》1982,28(4):855-863
The level of cytoplasmic calcium ions appears to be important in the control of murine erythroleukemia (MEL) cell differentiation. Our interest in this study focuses on the relationship between the regulation of calcium concentration and differentiation. We used the fluorescent membrane probe DiOC6 to examine the relationship between MEL cell mitochondria and changes in cytoplasmic calcium levels occurring at the initiation of commitment. Fluorescence microscopy reveals the selective association of DiOC6 with MEL cell mitochondria, where an enhanced fluorescence is observed. Treatment of cells with dimethylsulfoxide (DMSO) or other inducers causes a decrease in mitochondria-associated fluorescence levels that occurs with the initiation of commitment. A decrease in DiOC6 fluorescence is caused by agents that reduce mitochondrial membrane potential, but is only slightly affected by agents that alter plasma membrane potential. Amiloride and EGTA, agents that prevent commitment and inhibit calcium uptake, also prevent the decrease in DiOC6 uptake caused by DMSO. The effect of DMSO on MEL cell mitochondria is mimicked by FCCP, a proton ionophore that dissipates mitochondrial membrane potential. FCCP also caused MEL cell mitochondria to release calcium into the cytoplasm. When MEL cells are treated with DMSO plus FCCP, commitment is initiated without the lag period observed when cells are treated with DMSO alone. These results are consistent with the hypothesis that mitochondrial transmembrane potential is important in the regulation of cytoplasmic calcium levels at the time of commitment of MEL cells to terminal differentiation. 相似文献
56.
57.
Appropriate low dosages of vincristine stimulate megakaryocytopoiesis and produce thrombocytosis. In this study of the thrombocytotic action of vincristine, administration of a single dose of 0.1 mg/kg to rats produced an increase in megakaryocyte concentration, diameter and 24 h [3H]thymidine labelling index. Transfusion of one body equivalent of platelets from normal donors prevented stimulation of megakaryocytopoiesis by vincristine whereas platelets from vincristine-treated donors did not. These results suggest that vincristine stimulates megakaryocytopoiesis by altering the functional role of circulating platelets in the regulation of thrombopoiesis. 相似文献
58.
MS Siniakov IG Kharitonenkov IM Aref''ev AP Es''kov 《Canadian Metallurgical Quarterly》1980,20(1):42-45
Following acute alcohol administration (80-160 mg/100 g body weight) histamine levels of rat brain cortex and thalamus were elevated and histidine decarboxylase activity was decreased. The effect was less pronounced after chronic alcohol treatment (15% v/v in drinking water for 4 weeks). In the striatum there was no change in the metabolic pattern of histamine. Histamine-N-methyltransferase was unaffected in either case. Depolarisation-induced release of histamine was inhibited by alcohol in the hypothalamus, thalamus and cortex. The results indicate that ethanol affects the histamine metabolism and release processes in the histaminergic pathway of the brain. 相似文献
59.
60.
AA Vazina AM Gadzhiev AM Matiushin IG Fel'dman AG Khabakhpashev 《Canadian Metallurgical Quarterly》1977,22(2):351-353
The results of applying linear position sensitive proportional counters to diffuse small-angle synchrotron radiation scattering to biopolymer solutions are presented. Synchrotron radiation of the VEPP-3 storage ring (Institute of Nuclear Physics, Novosibirsk) was used. On the basis of small-angle scattering curve obtained from protein pepsinogen it has been shown that the exposure is about 100 times less than with conventional X-ray technique. 相似文献