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J DeMarco N Brodtmann 《Journal of environmental pathology, toxicology and oncology》1987,7(7-8):199-212
The first attempt to provide a data base for comparing a pilot and full scale system for various organics produced results that require further investigation. Although both of the pilot systems had longer average contact times than their respective full scale systems, a uniform pattern of longer service time for the different substances evaluated did not occur. These results may not be consistent with the data collected using pilot contactors in series to observe the effect of contact time. The series pilot contactor system provided data that show the effect of varying empty bed contact time on the removal of the organic substances studied. Improved effluent quality was generally achieved with increased contact time. A pilot series system similar to the one used is considered essential in collecting and interpreting design data. A method of statistical interpretation of the results was developed that shows promise for use in evaluating pilot column results. Further evaluation is required to assess that all pertinent factors were properly controlled during the investigation. Also, repeat testing will be conducted, attempting to control more closely the contact times between the pilot and full scale systems. The comparative granular activated carbon particle sizes also will be more closely examined. Although pilot to full-scale comparisons have been successfully performed for single parameters, the results for multiple organics have not been previously reported. Such a data base, if properly collected, will provide invaluable background in assessing what types of design safety factors are required when using pilot column data to predict full scale results for a naturally occurring mixture of organic substances. 相似文献
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Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
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DL-2-amino-4-phosphonobutyric acid does not eliminate "ON" responses in the visual system of goldfish.
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P J DeMarco Jr J Bilotta M K Powers 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(9):3787-3791
DL-2-Amino-4-phosphonobutyric acid (APB) suppresses activity in retinal ON pathways. It is generally assumed that loss of the ON pathway would result in loss of ON responses in the visual system. We tested this assumption by recording activity from the optic nerves of intact goldfish (Carassius auratus) before and after intraocular injection of APB. Whole-nerve responses to increments and decrements of light were compared to electroretinogram responses and to tectal evoked potentials. APB severely reduced the amplitude of the electroretinogram b-wave but left ON and OFF responses from the optic nerve and tectum intact, although decreased in sensitivity. We conclude that APB does not completely eliminate ON responses in the visual system, at least in goldfish. The selectivity and effectiveness of APB must be evaluated in other species before this agent can be relied upon as a useful tool in understanding the roles of ON and OFF pathways in visual function. 相似文献
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Jonathan H. Marsh Willi Kreis Barbara Barile Silvia Akerman Philip Schulman Steven L. Allen Linda C. DeMarco Michael W. Schuster Daniel R. Budman 《Cancer chemotherapy and pharmacology》1993,31(6):481-484
Summary Eight patients, of whom four had acute myeloid leukemia (AML) and four had chronic myeloid leukemia (CML) blast crisis, were treated with a combination of cytosine arabinoside (ARA-C: 1,600 mg/m2 in three patients, 1,200 mg/m2 in five patients), tetrahydrouridine (THU: 2,800 mg/m2 in two patients, 2,646 mg/m2 in one patient, 2,100 mg/m2 in five patients), and carboplatin (900 mg/m2 in four patients, 720 mg/m2 in one patient, 450 mg/m2 in three patients). As a result of this treatment, five of the eight patients became aplastic. Two of the four patients with CML blast crisis reverted to the chronic phase and two of the four patients with acute nonlymphocytic leukemia (ANLL) attained a remission (one partial remission and one complete remission). The major toxicities included myelosuppression, unacceptable hepatotoxicity, and diarrhea. Pharmacokinetics studies revealed that the addition of carboplatin did not significantly change the disposition of ARA-C. ARA-C levels were not significantly changed in comparison with those obtained in a prior study of ARA-C with THU (ARA-C plasma levels at 3 h, 2630±1170 ng/ml).Supported by the Don Monti Memorial Research Foundation 相似文献