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21.
Native associations of early hematopoietic stem cells and stromal cells isolated in bone marrow cell aggregates 总被引:4,自引:3,他引:4
In suspensions of murine bone marrow, many stromal cells are tightly entwined with hematopoietic cells. These cellular aggregations appear to exist normally within the marrow. Previous studies showed that lymphocytes and stem cells adhered to stromal cells via vascular cell adhesion molecule 1 (VCAM1). Injection of anti-VCAM1 antibody into mice disrupts the aggregates, showing the importance of VCAM1 in the adhesion between stromal cells and hematopoietic cells in vivo. Early hematopoietic stem cells were shown to be enriched in aggregates by using a limiting-dilution culture assay. Myeloid progenitors responsive to WEHI-3CM in combination with stem cell factor (c-kit ligand) and B220- B-cell progenitors responsive to insulin-like growth factor-1 in combination with interleukin-7 are not enriched. We propose a scheme of stromal cell-hematopoietic cell interactions based on the cell types selectively retained within the aggregates. The existence of these aggregates as native elements of bone marrow organization presents a novel means to study in vivo stem cell-stromal cell interaction. 相似文献
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M ODowd T Geoghegan PL Munk G McAuley WC Torreggiani 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):386-388
Osseous haemophilic pseudotumours are uncommon. The commonest sites of involvement are the femur and the pelvis. Trauma is the initiating factor in most reported cases and repeated bleeding into the lesion contributes to their growth. Most lesions grow slowly and are often asymptomatic. Complications include massive haemorrhage, infection and pathological fracture. We present an extremely unusual presentation where a large haemophilic pseudotumour of the pelvis extended to impinge the adjacent colon, resulting in large bowel obstruction. 相似文献
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The coeliac iceberg in Italy. A multicentre antigliadin antibodies screening for coeliac disease in school-age subjects 总被引:8,自引:0,他引:8
C Catassi E Fabiani IM Rätsch GV Coppa PL Giorgi R Pierdomenico S Alessandrini G Iwanejko R Domenici E Mei A Miano M Marani G Bottaro M Spina M Dotti A Montanelli M Barbato F Viola R Lazzari M Vallini G Guariso M Plebani F Cataldo G Traverso C Ughi G Chiaravalloti M Baldassarre P Scarcella F Bascietto L Ceglie A Valenti P Paolucci M Caradonna E Bravi A Ventura 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(S412):29-35
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched. 相似文献
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Antignani PL 《Current vascular pharmacology》2003,1(2):205-216
Peripheral arterial disease (PAD) is a common but under-recognized problem. Intermittent claudication is the most frequent symptom of PAD, although the diagnosis of PAD is often overlooked until the patient is presented with limb-threatening ischemia. Importantly, PAD is a marker of generalized atherosclerosis and is closely associated with coronary and cerebrovascular disease. The primary causes of death in patients with PAD are myocardial infarction and stroke. Reducing risk factors is an integral and aggressive part of the treatment regimen. The recognition and diagnosis of PAD, combined with its appropriate medical management, may well reduce the overall risk of cardiovascular morbidity. When diagnosed early, both exercise and pharmacotherapy can ameliorate symptoms of claudication. augment functional performance, and improve quality of life. This review focuses on the general medical management and specific therapeutic options. Because PAD is a manifestation of generalized atherosclerosis, the principal issue in medical management of PAD is a treatment plan that modifies known risk factors for atherosclerosis and its atherothrombotic complications. All patients with PAD should be receiving antiplatelet therapy to prevent ischemic events and ACE inhibitors should be used if appropriate. Medical treatment for patients with claudication includes exercise in rehabilitation and drug therapy. It is also recognized that selected patients with claudication symptoms may benefit from catheter-based interventions, and most PAD patients with critical leg ischemia require revascularization procedures. Although many therapies for claudication have been thoroughly investigated, research continues on new treatments. In contrast, more prospective, randomized trials are needed to evaluate various therapies for treating patients with PAD. 相似文献
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Posteroanterior (PA) and caudally angulated PA views were obtained in 20 patients undergoing routine coronary arteriography. Although the left main coronary artery (LMCA) was seen well on both views in all patients, the PA-caudal view improved depiction of the LMCA bifurcation in 15 (75%). In addition, the PA-caudal view markedly improved depiction of the circumflex artery, affording optimal depiction of this artery and its branches in 78%-89% of patients. Neither the PA nor the PA-caudal view allowed adequate depiction of the left anterior descending artery. Thus, the PA-caudal view should supplant the PA view in routine coronary arteriography. 相似文献