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Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve.  相似文献   
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Results of previous studies have shown that when rats consume higher concentrations of ethanol during initiation both the amount consumed and the pattern of consumption change with the return to a lower concentration. In this study, an across-sessions breakpoint procedure in the sipper-tube model was used to examine the effect that experience with drinking higher concentrations (a concentration manipulation) of both ethanol and sucrose had on appetitive and consummatory behaviors. A follow-up study was then conducted in the ethanol-consuming group with across-session breakpoint and intake examined before, during, and after a 3% sucrose/10% ethanol solution was presented in the sipper tube. As ethanol concentration increased, intake was not changed. Exposure to higher ethanol concentrations had no effect on the amount of 10% ethanol consumed when retested. The exposure tended to increase appetitive behavior (breakpoint), but this effect was not unique to ethanol, as rats self-administering 3% sucrose showed a similar increase. When the combined ethanol-sucrose solution was available, a significant increase in both intake and appetitive responding occurred; however, there was no change from prior intake or breakpoint when 10% ethanol was retested. That the addition of sucrose to the ethanol solution significantly increased appetitive and consummatory behaviors supports the suggestion that the composition of the alcoholic beverage can have a strong influence over the control of self-administration. Because most consumption of ethanol by human beings is in solutions that contain mixers that alter the taste of the solution, this taste factor needs to be considered in the regulation of ethanol drinking.  相似文献   
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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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Abstract: Twenty-six part-time students from a variety of professional backgrounds are enrolled in the first year of a Graduate Diploma in Social Science (Drug Dependence) at the Phillip Institute of Technology in Victoria. The course is conducted under the auspices of the School of Social Work and commenced in 1984. It is argued that the graduates from this unique course could play a key role in providing personnel to fill positions in the areas of clinical work, staff development, drug education, programme development and management and research.  相似文献   
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