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991.
MW Fried DG Connaghan S Sharma LG Martin S Devine K Holland A Zuckerman S Kaufman J Wingard TD Boyer 《Canadian Metallurgical Quarterly》1996,24(3):588-591
Hepatic venoocclusive disease (VOD) is a common, life-threatening complication of bone marrow transplantation (BMT). Portal hypertension is usually present and accounts for many of the clinical manifestations of this syndrome. We describe the results of transjugular intrahepatic portosystemic shunt (TIPS) for the management of VOD after BMT TIPS was performed in six patients with histologically confirmed VOD who had progressive jaundice and ascites. Portal hypertension was improved by TIPS in all patients (mean portal pressure gradient before TIPS, 20.2 +/- 4.6 vs. 6.7 +/- 1.9 mm Hg post-TIPS, P < .004). Three patients who underwent TIPS late in the course of VOD did not demonstrate any clinical improvement after TIPS and expired within 2 weeks of the procedure. The remaining three patients had less advanced disease and demonstrated decreases in serum bilirubin, improvement in coagulopathy, and decreased ascites after TIPS. Two patients subsequently expired, one with persistent histological changes of VOD. The lone survivor continues to do well with resolution of ascites, jaundice, and coagulopathy as of her last outpatient visit. TIPS was an effective method for portal decompression in patients with VOD after BMT, and was associated with clinical improvement in some patients. However, these effects may be transient and may not improve overall survival. 相似文献
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993.
Cows, ewes, and mares varied considerably in susceptibility to toxicoses from the oral administration of the piperidine alkaloid, coniine. Cows were most susceptible and ewes least. Only calves had teratogenic effects from maternal administration of coniine during gestation; lambs and foals were apparently resistant. Results suggest that the marked differences between cattle and sheep are probably not due to variation in gut absorption or rumen metabolism. 相似文献
994.
Hemoglobin synthesis in cell hybrids formed between teratocarcinoma and Friend erythroleukemia cells
MW McBurney 《Canadian Metallurgical Quarterly》1977,12(3):653-662
Viable hybrid cells have been isolated following fusion of Friend erythroleukemia cells and undifferentiated teratocarcinoma cells. The hybrids formed between near-diploid parental cells resembled Friend cells in the ability to grow in suspension and to synthesize hemoglobin in the presence of the chemical inducers dimethyl sulfoxide (DMSO) and ouabain. Erythropoietin (EPO) was effective in inducing hemoglobin synthesis in some of the hybrid cell lines. The hemoglobins synthesized by the hybrids were of the adult forms, but were quantitatively different from those hemoglobins synthesized by the parental Friend cells, suggesting that the fusion event modulated the expression of the hemoglobin chain genes. 相似文献
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The effects of intracerebral microinjections of Nembutal into different brain areas, with the purpose of reproducing the behavioural and EEG signs of barbiturate narcosis, have been studied and analyzed. Cats were implanted for polygraphic study of the sleep-wakefulness cycle and bilateral brain canulae were also placed in strategic brain areas. The most striking results was the controlateral turning after unilateral injections of Nembutal in the nigra, suggesting a loss of balance among the actions of the nigro-striatal-cortical pathways on both sides. The sequence of events produced by intravestibular injections of Nembutal suggests that the drug, when injected intraperitoneally, acts also upon the vestibular system. This data stresses the importance of localized intracerebral microinjections of drugs to determine and differentiate their action mechanisms when injected in an intraperitoneal or intravenous way. 相似文献
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Sture Hägglund Johan Elfström Hans Holmgren Olle Rosin Ove Wigertz 《Computers & Education》1982,6(1):67-76
When using the computer as a tool for learning, it is useful to distinguish between the contents and the realization aspects of an interactive session. We describe an approach which makes this distinction explicit to the author by viewing the programming process as one of giving independent specifications of: (a) data. i.e. what is to be learned, and (b) control, i.e. the particulars of the dialogue.A system. MEDICS, for training medical students in clinical decision making is presented as an illustration of the approach. We stress the importance of providing an interactive environment supporting powerful editing operations as the primary tool for the author. The paper specifically describes the MEDICS environment for construction of medical simulations and how control of execution is specified. 相似文献