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排序方式: 共有573条查询结果,搜索用时 265 毫秒
21.
Erin E. Hillhouse Stéphanie Thiant Moutuaata M. Moutuou Félix Lombard-Vadnais Rachel Parat Jean-Sébastien Delisle Imran Ahmad Denis-Claude Roy Martin Guimond Jean Roy Sylvie Lesage 《Biology of blood and marrow transplantation》2019,25(1):19-25
Chronic graft-versus-host disease (cGVHD) is a major complication, affecting 50% to 80% of long-term survivors of allogeneic hematopoietic stem cell transplantation. Current cGVHD therapies are neither specific nor curative, and patients are typically maintained for several months to years under immunosuppressive regimens that are associated with important side effects and increased susceptibility to life-threatening infections. As a result, continued investigation into the pathology of the disease and the search for novel diagnostic and therapeutic strategies to treat cGVHD remains a high priority. We report that the cellular dynamics of various immune cell subsets are related to cGVHD onset and severity in a cohort of allogeneic hematopoietic stem cell transplantation recipients. We document a decrease in the proportion of CD45RO+ CD4?CD8? (double-negative [DN]) T cells at the onset of cGVHD, a time at which serum levels of B cell activating factor and B cells are increased. We also find that DN T cell levels are correlated with cGVHD severity. Our present findings are in line with the view that activated DN T cells exhibit their immunoregulatory potential by eliminating B cells in vivo. Taken together, these findings suggest that maintaining elevated DN T cell numbers before the onset of cGVHD may prevent pathological B cell responses. 相似文献
22.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
23.
Mutations in the LEMD3 gene were recently incriminated in Buschke–Ollendorff syndrome (BOS) and osteopoikilosis, with or without melorheostosis. The relationship of this gene with isolated sporadic melorheostosis is less clear. We investigated LEMD3 in a two-generation BOS family showing an extremely variable expression of the disease, in a sporadic patient with skin features of BOS, and in an additional subject with isolated melorheostosis. We identified two different mutations, both resulting in a premature stop codon, in the two cases of BOS. The mutation (c.2564G>A) reported in the familial case is novel, while that observed in the sporadic case (c.1963C>T) has been previously reported in an American woman with osteopoikilosis and melorheostosis who had a family history of isolated osteopoikilosis. The search for mutations in DNA extracted from the peripheral blood, as well as skin and bone biopsies of the patient with melorheostosis failed to identify any pathogenic change. Our results further expand the LEMD3 mutation repertoire, corroborate the extreme interfamilial and intrafamilial clinical variability of LEMD3 mutations, and underline the lack of a clear phenotype–genotype correlation in BOS. The present study supports the general conclusion that LEMD3 mutations do not contribute to isolated sporadic melorheostosis. The genetic or epigenetic influences that are responsible for the development of melorheostosis require further investigation. 相似文献
24.
Protein energy malnutrition (PEM) is known to depress cell-mediated immunity. Its effect on humoral immunity is less clear-cut. The purpose of the study was to assess seroconversion following measles vaccination according to child nutritional status as assessed by anthropometry and serum thyroxine-binding prealbumin (TBPA). Prior to vaccination, 200 Malian children aged 8-22 months (mode: 9 months) and free of infection were weighed and measured. A venous blood sample was drawn for determination of serum TBPA by radial immunodiffusion and of measles specific immunoglobulins (Ig) by Enzyme-linked Immuno-Sorbent Assay (ELISA). IgG and IgM were again assayed 6 weeks post-vaccination after excluding pre-immune subjects. Seroconversion took place in 91 per cent of the children (95 per cent confidence interval: 86-96 per cent). Based on the NCHS standards, 30 per cent of the children were wasted (weight-for-height less than -2.0 SD) and 18 per cent were stunted (height-for-age less than -2.0 SD). Low serum TBPA (less than 10 mg/dl) was found in 38 per cent of them. TBPA was significantly correlated with weight-for-height and weight-for-age (P less than 0.001), but not with height-for-age. Seroconversion was not significantly related to age, anthropometric indices or TBPA. This study using sensitive methods for the assessment of protein status and of the immune response confirms that children should be vaccinated against measles irrespective of their nutritional status, and PEM was not shown to impair their antibody response. 相似文献
25.
26.
This paper focuses on changes in vitamin A (VA) intakes as part of the evaluation of a pilot project on social marketing of red palm oil (RPO) as a VA supplement for mothers and children in central-north Burkina Faso. The objectives of the 30-month project are to demonstrate the feasibility and effectiveness of introducing RPO in non-consuming areas. RPO is collected from women in the South-West region and it is sold in project sites by village volunteers. RPO is promoted by community workers trained in persuasive communication and social marketing. The target population is free to buy and consume RPO. Evaluation design includes data collected at onset, then 12 and 24 months later, from the same sample of 210 mothers and their children randomly selected in seven project sites. Children were 1 to 3 years old at onset. Blood samples were collected at baseline from mothers and children for serum retinol determination by HPLC. VA intakes are estimated by a semi-quantitative food frequency questionnaire, using the conventional beta-carotene to retinol conversion factors and the newly revised lower factors. VA deficiency is a major public health problem in the area: 64% of mothers and 85% of children had serum retinol concentrations < 0,70 mumol/l at baseline. VA came mainly from plant foods, particularly fruits and dark green vegetables which provided more than 90% of the dietary VA at onset of the project. Mean vitamin A intakes are low. We found 138 106 mug ER for the children and 302 +/- 235 microg ER for the mothers with conventional factors and 64 +/- 58 microg ER and 133 +/- 162 microg ER, respectively, with the revised factors. One year later, one third of respondents had consumed RPO in the previous week, and it supplied around 56% of the VA intake of children and 67% of mothers (36% and 46% respectively for the whole group). VA intakes were significantly increased at 510 +/- 493 microg ER and 801 +/- 913 microg ER for the children and their mothers respectively (347 +/- 443 microg ER and 568 +/- 803 microg ER respectively, with the revised factors). Analyzing serum retinol and dietary data collected at baseline, it was found that VA intakes < 62,5% of safe level of intake were highly sensitive to low serum retinol (< 0,70 micromol/l) and using revised conversion factors to assess total VA intake slightly enhanced sensitivity. The proportion of mothers and children at risk of inadequate VA intake changed from nearly 100% at baseline to 60% one year later. The results show that promoting RPO (and other VA rich foods) was effective in improving VA intakes. This improvement will hopefully be sustained and even further enhanced during the remaining 12 months of the project, after which repeated measurement of serum retinol and VA intakes will allow the actual impact of the project to be truly assessed. 相似文献
27.
Background
Fanconi anemia (FA) is a complex recessive genetic disease characterized by progressive bone marrow failure (BM) and a predisposition to cancer. We have previously shown using the Fancc mouse model that the progressive BM failure results from a hematopoietic stem cell defect suggesting that function of the FA genes may reside in primitive hematopoietic stem cells. 相似文献28.
29.
Delisle MF Valimohamed F Money D Douglas MJ 《The Journal of maternal-fetal medicine》2000,9(4):242-247
A 30-year-old woman with von Hippel-Lindau disease presented at 30 weeks' gestation with a symptomatic cerebellar hemangioblastoma. She underwent a craniotomy for complete removal of the tumor. The postoperative period and the remaining of the pregnancy were uneventful. She delivered under epidural anesthesia after induction for postterm. 相似文献
30.