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排序方式: 共有1968条查询结果,搜索用时 31 毫秒
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A model is developed to describe protein release kinetics from injectable, polymer solution depots which undergo rapid phase inversion on injection. The model consists of a polymer-rich phase and a solvent-rich phase, consistent with experimentally observed phase inversion morphology. Equations in the polymer-rich phase are based on diffusion-reaction mass balances for solvent, water and dissolved drug, and the rate of dissolution of dispersed drug particles. Equations in the water-rich phase are also of the diffusion-reaction type. Transport parameters in the polymer-rich phase are coupled to the ternary thermodynamics through friction formalism, and remaining parameters are estimated from literature data, leaving two free parameters: volume fraction of water-rich phase (epsilon) and k, the mass-transfer coefficient for bath-side transfer of the protein. Variations of these parameters lead to predictions of release profiles that vary from a rapid, burst-like behavior followed by a locking-in of the polymer-rich phase, to a uniform, zero-order profile. Comparisons are made to lysozyme release data for three systems: PLGA solutions in N-methlypyrollidinone (NMP), PLA solutions in NMP, and the latter with added Pluronic. Good agreement between model predictions and data is shown; in particular, the transition from rapid release to zero-order kinetics that occurs on addition of Pluronic is illustrated. 相似文献
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S. H. Pross Y. Nakano S. McHugh R. Widen T. W. Klein H. Friedman 《Immunopharmacology and immunotoxicology》1992,14(3):675-687
Marijuana, and specifically its psychoactive component, THC, can up or down regulate lymphocyte proliferation in murine spleen cells depending in part on the method used to stimulate the cells. This study identifies a difference in THC induced disregulation using cells derived from two different secondary lymphoid organs, the spleen and the lymph node. It was found that THC treatment of mitogen (concanavalin A or phytohemagglutinin) stimulated cells derived from either organ resulted in suppression of the proliferative response. In contrast, spleen cells stimulated with anti-CD3 antibody and treated with low doses of THC displayed an enhanced proliferation whereas the response in lymph nodes did not change. The cell type involved with this THC immunoenhancement in spleen cells was found to be the Ly2 cell. Further differences in the THC modulation of Ly2 spleen cells as compared to lymph node cells were noted following stimulation with PHA. Proliferation of Ly2 cells of splenic origin was inhibited with low doses of THC whereas the Ly2 cells of lymph node origin were more resistant to this drug induced suppression. This study, therefore, demonstrates differences in the immunomodulatory capability of THC dependent upon the organ source of the lymphocytes. 相似文献
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Gordon Winocur Fergus I M Craik Brian Levine Ian H Robertson Malcolm A Binns Michael Alexander Sandra Black Deirdre Dawson Heather Palmer Tara McHugh Donald T Stuss 《Journal of the International Neuropsychological Society》2007,13(1):166-171
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed. 相似文献
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Mechanisms of quinolone resistance in Escherichia coli: characterization of nfxB and cfxB, two mutant resistance loci decreasing norfloxacin accumulation. 总被引:29,自引:23,他引:6 下载免费PDF全文
D C Hooper J S Wolfson K S Souza E Y Ng G L McHugh M N Swartz 《Antimicrobial agents and chemotherapy》1989,33(3):283-290
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Renal transplantation for patients 60 years of older. A single-institution experience. 总被引:1,自引:0,他引:1 下载免费PDF全文
E Benedetti A J Matas N Hakim C Fasola K Gillingham L McHugh J S Najarian 《Annals of surgery》1994,220(4):445-460
OBJECTIVE: The authors reviewed renal transplant outcomes in recipients 60 years of age or older. BACKGROUND: Before cyclosporine, patients older than 45 years of age were considered to be at high risk for transplantation. With cyclosporine, the age limits for transplantation have expanded. METHODS: The authors compared patient and graft survival, hospital stay, the incidence of rejection and rehospitalization, and the cause of graft loss for primary kidney recipients 60 years of age or older versus those 18 to 59 years of age. For those patients > or = 60 years transplanted since 1985, the authors analyzed pretransplant extrarenal disease and its impact on post-transplant outcome. In addition, all surviving recipients > or = 60 years completed a medical outcome survey (SF-36). RESULTS: Patient and graft survival for those > or = 60 years of age versus those 18 to 59 years of age were similar 3 years after transplant. Subsequently, mortality increased for the older recipients. Death-censored graft survival was identical in the two groups. There were no differences in the cause of graft loss. Those 60 years of age or older had a longer initial hospitalization, but had fewer rejection episodes and fewer rehospitalizations. Quality of life for recipients 60 years of age or older was similar to the age-matched U.S. population. CONCLUSION: Renal transplantation is successful for recipients 60 years of age or older. Most of them had extrarenal disease at the time of transplantation; however, extrarenal disease was not an important predictor of outcome and should not be used as an exclusion criterion. Post-transplant quality of life is excellent. 相似文献
10.
G Nestadt A J Romanoski J F Samuels M F Folstein P R McHugh 《The American journal of psychiatry》1992,149(9):1228-1233
OBJECTIVE: The aim of this study was to assess the relationships between specific personality disorders and DSM-III axis I conditions in a community sample. METHOD: A total of 810 subjects were examined by psychiatrists in the second stage of the Eastern Baltimore Mental Health Survey, part of the Epidemiological Catchment Area Program of the National Institute of Mental Health. A semistructured examination, the Standardized Psychiatric Examination, was employed to assess axis I and axis II conditions. Scales for compulsive and antisocial personality disorders were derived from DSM-III criteria. The relationships between scores on these personality disorder scales and the presence of generalized anxiety disorder, alcohol use disorders (alcohol abuse and alcohol dependence), and simple phobia were evaluated by using logistic regression. RESULTS: Higher compulsive personality scores were associated with a greater odds of generalized anxiety disorder and simple phobia but a smaller odds of alcohol use disorders. In contrast, higher antisocial personality scores were associated with a greater odds of alcohol use disorders but a smaller odds of generalized anxiety disorder. There was no relationship between antisocial personality scores and simple phobia. CONCLUSIONS: Personality disorders have specific relationships to axis I conditions, which suggests different vulnerabilities but also different protective influences. 相似文献