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171.
Solid dispersions of naltrexone in natural glycerides were used to form injectable implants which continuously release narcotic antagonists in vivo. The dispersions were formed and tested either as small cylindrical pellets, e.g. l x 3.0 mm in size, or as particles with diameters in size ranges between 125-250 mu, that are suspended in an aqueous methyl cellulose solution. Both types of implants delivered naltrexone to mice at rates that were effective in blocking the antiociceptive action of morphine for at least one month. The rate of naltrexone release was controlled by altering its concentration in the dispersion and by varying the glyceride composition. Degradation and absorption of the implants were found to depend on their composition, dimensions and location in the body. No appreciable tissue incompatibility was seen in mice, rats, rabbits, monkeys and swine, even when long-lasting preparations were removed a year after treatment.  相似文献   
172.
A pilot study was conducted in the first of two monkeys using either radiolabeled Dm-Na-P or radiolabeled hydrocortisone sodium succinate, together with lidocaine HCl. This study indicated an approximately tenfold increase in the quantity of Dm-Na-P delivered to the test electrodes (4 mA; 20 minutes) whereas the quantity of hydrocortisone delivered from the test electrodes was only marginally (approximately 10%) increased as compared with that from the controls. In terms of an anti-inflammatory activity, the effective dose of Dm-Na-P in all tissue layers underlying the test electrodes was at least tenfold that of the hydrocortisone. Therefore, further trials with hydrocortisone were abandoned. In the second animal, positive test electrodes (5 mA; 20 minutes, were sited over five joints on the right side of the body and matching control electrodes (0 mA; 20 minutes) were placed over corresponding joints on the left side of the body. The control and test electrodes each contained 1.0 ml tritium-labeled Dm-Na-P (approximately 4.0 mg) and 2.0 ml 4% lidocaine HCl (80 mg). Local tissue concentrations of Dm-Na-P were higher than those that would be obtained by systematic therapy and lower than would be obtained by local injection.  相似文献   
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Cluster analysis was used to identify two homogeneous clusters of 8-9 1/2-year-old children who misarticulated /s/, /r/, or both. The analysis was based on the children's scores on 40 measures of language, reading, auditory processing, and other variables. Discriminant function analysis was then used to identify a subset of five measures and a means of computing classification scores. These measures and the classification scores can be used to identify the cluster membership of new subjects. The use of classification scores for identifying cluster membership was cross-validated against cluster analysis of a second group of children. The two clusters are described in terms of their performance on language and reading measures.  相似文献   
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