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1.
Maria A. Giovino Robert J. Hawley Matt W. Dickerson Roseann Glaser Deborah H. Meshulam Robert Ardtsini Margaret D. Rosa Rod L. Monroy 《Xenotransplantation》1997,4(2):112-119
Abstract: Establishment of mixed bone marrow chimerism in pig-to-primate transplantation, as a means of inducing specific immune tolerance, will require that both immune and nonimmune barriers be overcome. As a preliminary step in evaluating nonimmune barriers in this system, we have developed an in vitro model of engraftment in which long-term culture of porcine bone marrow-derived hematopoietic cells is supported on preformed primate bone marrow stromal layers. In the absence of cytokine supplementation, primate stromal cells were unable to support long-term porcine hematopoiesis in these cultures. Supplementation with porcine Steel Factor was required for long-term maintenance of hematopoietic progenitor cell content and total hematopoietic activity. Addition of porcine IL-3, in combination with porcine Steel Factor, increased long-term progenitor cell content and hematopoietic activity on primate stroma to levels comparable to that obtained in cultures on porcine stroma. The combination of porcine GM-CSF and Steel Factor increased progenitor cell content and hematopoietic activity early in the cultures, but had little effect in long-term cultures. The Steel Factor and IL-3 combination was species-specific in its action in these cultures, as the corresponding human cytokines were unable to effectively support long-term porcine hematopoiesis. Likewise, the combination of porcine cytokines had only minimal effects on long-term bone marrow culture of primate CD34+ cells I on primate stroma. 相似文献
2.
Wynn L. Walker Elliot M. Landaw Richard E. Dickerson David S. Goodsell 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(11):5634-5639
Three- and four-ring polyamides containing N-methylimidazole and N-methylpyrrole, and their hairpin-linked derivatives, bind side-by-side in the minor groove of DNA in a sequence-specific manner. The sequences recognized by side-by-side molecules are dependent on the pairings of the polyamide rings to the bases. In this study we report a mathematical model for estimating the free energies of binding for γ-aminobutyric acid-linked polyamides to 5- and 6-bp DNA sequences. The model parameters are calibrated by a least-squares fit to 35 experimental binding constants. The model performs well in cross-validation experiments and the parameters are consistent with previously proposed empirical rules of polyamide–DNA binding. We apply the model to the design of targeted polyamides, evaluating the ability of the proposed polyamides to bind to a DNA sequence of interest while minimizing binding to the remaining DNA sequences. 相似文献
3.
Dr. Rex O. Brown Pharm.D. Dr. Roland N. Dickerson Pharm.D. Dr. Emily B. Hak Pharm.D. Dr. J. Barret Matthews M.D. Dr. Lawrence J. Hak Pharm.D. 《Pharmacotherapy》1997,17(4):796-800
A pharmacist consult service was developed to evaluate the appropriateness of enteral feeding through a permanent ostomy in 24 nonambulatory patients with severe developmental disabilities. Several problems with enteral nutrition were identified. Policies to improve them were instituted, and several educational presentations were made. Pharmacists' actions were implemented, including assessment of energy needs by indirect calorimetry and rearrangement of enteral feeding schedules to achieve optimal nutrition support and pharmacotherapy administration. By the fourth month of the consult service, body weight in these patients increased from 101 ± 6% of baseline to 109 ± 7% (p<0.05). Weight continued to increase through the seventh month of the consult service to 116 ± 12% of baseline (p<0.0001). Measured resting energy expenditure for the group was 889 ± 170 kcal/day compared with the predicted 1055 ± 163 kcal/day. 相似文献
4.
Laurie M Morgan Roland N Dickerson Kathryn H Alexander Rex O Brown Gayle Minard 《Nutrition in clinical practice》2004,19(5):511-517
BACKGROUND: The intent of this study was to ascertain the adequacy of delivery of enteral nutrition (EN) to critically ill adult multiple trauma patients and to identify potential detrimental factors that affect EN delivery. METHODS: Retrospective observational study. Trauma intensive care unit (TICU) in a university-affiliated hospital. Adult patients (>/=18 years of age) admitted to the TICU who received enteral feeding. RESULTS: Fifty-six adult patients were enrolled for study. Patients received, on average, 67% +/- 19% of what was prescribed for 5.7 +/- 2.0 days. A total of 222 occurrences for temporary discontinuation of tube feeding were identified. Gastrointestinal intolerance, as defined by a gastric residual volume of >150 mL, abdominal pain, or >3 liquid stools per day, accounted for only 11% of the occurrences for discontinuation of feeding. Surgery (27%) and diagnostic procedures (15%) represented the majority of reasons for inadequate nutrient delivery. Minor factors for EN interruptions were mechanical feeding tube problems (8%), pharmacy delivery delay (4%), and miscellaneous factors (3%). Multiple and unknown reasons contributed to 14% and 18% of the occurrences, respectively. CONCLUSIONS: Surgery and diagnostic procedures accounted for the largest factor in enteral feeding discontinuations in our critically ill trauma patients. Gastrointestinal intolerance contributed a minor role in the temporary discontinuation of enteral feeding. 相似文献
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D. Dickerson B. Adams G. Engelbrecht G. Boltman R. Hickman D. Kahn 《Transplant international》1992,5(Z1):S63-S64
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period. 相似文献
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