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101.
102.
Fanconi anemia is an autosomal recessive disease characterized by a high risk of developing bone marrow (BM) failure and acute myelogenous leukemia. We studied growth of hematopoietic progenitor cells in long- term BM culture (LTBMC) in 8 persons with Fanconi anemia and BM failure. Although LTBMC were initiated with very few BM cells, an adherent layer formed in cultures from 7 persons. In these cultures, the number of nonadherent cells increased for 10 to 15 days. Cell growth continued until cultures were terminated at day 35 to 40. During the first 2 weeks of culture, most nonadherent cells were differentiated myeloid cells. By days 35 to 40, the adherent layer contained cells able to initiate secondary LTBMCs. These data indicate that hematopoietic precursors cells able to proliferate and differentiate in vitro are present in the BM of persons with Fanconi anemia and BM failure. They suggest that mechanisms other than absent precursor cells are responsible for BM failure in Fanconi anemia. 相似文献
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P. E. Pizao D. M. Lyaruu G. J. Peters J. van Ark-Otte B. Winograd G. Giaccone H. M. Pinedo 《British journal of cancer》1992,66(4):660-665
This study assessed the growth pattern, cellular organisation and chemosensitivity of established human tumour cell lines growing as postconfluent cultures in ''V''-bottomed, 96-well microtiter plates. Cross-sections of the colon (HT29, SW620, SW1116), ovarian (A2780) and head and neck (UM-SCC-22B) carcinoma microcultures allowed in situ evaluation of the cellular organisation in the wells. After 5 days of growth, every cell line had reached confluence, but each of them displayed a specific pattern of cell stacking which ranged from two to ten layers. Postconfluent HT29 cells displayed morphologic features suggestive of some degree of enterocytic differentiation. Growth and cytotoxicity could be studied reliably and reproducibly in this system with the sulforhodamine B protein assay. Against HT29 postconfluent cultures, the EC50''s (drug concentrations producing absorbance readings 50% lower than those of non-treated wells) of 5-fluorouracil and of the ether lipid, hexadecylphosphocholine, were 1 mM and 50 microM respectively. The possibility to perform chemosensitivity tests using semiautomated microtiter plate technology supports further evaluation of this system as an alternative antitumour drug testing model. 相似文献
105.
In 25 children with lymphoid malignancies, 96 high-dose methotrexate infusions (3 g/m2) with a duration of 24 h have been administered as a part of the treatment schedule. A lumbar puncture was performed to apply methotrexate intrathecally. The moment of lumbar puncture during the infusion was chosen at different times. In 76 of the infusions the concentration of methotrexate in the cerebrospinal fluid and in plasma were determined just prior to the intrathecal administration. From the second to the eighth hour after the initiation of the infusion the concentration of methotrexate in the cerebrospinal fluid appeared to be significantly lower than 16 or 24 h after the initiation of the infusion. Of all samples during the infusions, the plasma concentration varied a tenfold (2-20 X 10-5 mol/L), but the cerebrospinal fluid concentration of methotrexate varied about a 300-fold (3.5-900 X 10 mol/L). No correlation could be found between the plasma concentration of methotrexate and the cerebrospinal fluid concentration. It is concluded that the methotrexate concentration in the cerebrospinal fluid cannot be predicted by determining the plasma concentration. It lakes at least 8 h of infusion before a steady-state concentration of methotrexate is reached in the cerebrospinal fluid. In high-dose methotrexate infusions without intrathecal therapy, the dose of 3 g/m2 is the minimum amount of methotrexate to reach the minimum therapeutic concentration 5 X 107 mol/L) in the cerebrospinal fluid for the treatment of subclinical central nervous system invasion of malignant lymphoid cells. To maintain the minimum therapeutic concentration according to the CxT principle the duration of the infusion should be preferably longer than 24 h. 相似文献
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This article updates our previous article in this journal (Tryon & Winograd, 2001) by examining via meta-analyses results of recent studies, published from 2000 through 2009, that relate goal consensus and collaboration to treatment outcome. Specifically, 15 studies with a total sample size of 1,302 yielded a goal consensus-psychotherapy outcome effect size of .34 (SD = .19, p < .0001, 95% confidence interval = .23-.45), indicating that better outcomes can be expected when patient and therapist agree on therapeutic goals and the processes to achieve these goals. The collaboration-outcome meta-analysis based on 19 studies with a total sample of 2,260 patients yielded a mean correlation of .33 (SD = .17, p < .0001, 95% confidence interval = .25-.42), suggesting that psychotherapy outcome appears to be considerably enhanced when patient and therapist are actively involved in a cooperative relationship. We discuss therapeutic practices that follow from these findings. 相似文献
109.
Nguyen HN Winograd R Domingues GR Lammert F 《World journal of gastroenterology : WJG》2006,12(37):6008-6016
INTRODUCTION The spatial and temporal organization of gastrointestinal contraction waves seems to be a more important determinant of the flow of luminal contents than their number and amplitude[1,2]. Therefore, significant advances in understanding intest… 相似文献
110.
Introduction: A heavier weight in adults is becoming the norm rather than an abnormal weight. Whether the same trend is happening in children is unknown. Objective: To assess the perception of the weight of 4‐ to 5‐year‐old children and the recognition of overweight by both parents. Design: Population‐based survey. Participants: A questionnaire was sent to parents of 1155 4‐ to 5‐year‐old children. Results: In total, 439 questionnaires (35%) were returned. Of all, 90% of the children had a normal weight, 9.3% were overweight and 4.1% were obese. For all weight classes, the parents depicted the child as lighter on both the verbal and visual scale. Of all, 75% of mothers of overweight children stated that the child had a normal weight. In obese children, 50% of the mothers believed that the child had a normal weight. Conclusion: Children with a weight in the normal range were considered by their parents as a little too light or too light. Overweight was considered as normal weight, and obesity as normal or a little too heavy. The perception of a normal weight in children at 4–5 years is distorted. 相似文献