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Mohandas  N; Clark  MR; Kissinger  S; Bayer  C; Shohet  SB 《Blood》1980,56(1):125-128
Because of discrepancies between electronically and manually measured values of mean cell hemoglobin concentration (MCHC) encountered in studies of pathologic red cells, we studied the effect of cell water content on MCHC measurements by both methods. A series of red cell samples with varying water contents (54%-164% normal) were prepared from normal cells using the antibiotic nystatin. MCHC was then measured, using the microhematocrit centrifuge and three different electronic cell counters in common laboratory use. For MCHC values above 36 g/dl as measured by the spun hematocrit method, all three electronic counters under estimmated the MCHC, with increasing error as the true MCHC increased. For MCHC values below 30 g/dl, the values from two conductivity based instruments agreed with those from the spun hematocrit method, whereas one instrument based on light scattering overestimated the MCHC. These results indicate that inaccuracies in the measured mean cell volume (MCV) of dehydrated or otherwise undeformable cells may lead to spurious values for MCHC when electronic cell counters are used.  相似文献   
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This pilot study compared the effects of acute high-intensity intermittent exercise (HIIE) and moderate-intensity continuous exercise (MICE) on post-exercise VO2, fat utilization, and 24-hours energy balance to understand the mechanism of higher fat mass reduction observed after high-intensity interval training in post-menopausal women with overweight/obesity. 12 fasted women (59.5 ± 5.8 years; BMI: 28.9 ± 3.9 kg·m−2) completed three isoenergetic cycling exercise sessions in a counterbalanced, randomized order: (a) MICE [35 minutes at 60%-65% of peak heart rate, HRmax], (b) HIIE 1 [60 × (8-s cycling-12-s recovery) at 80%-90% of HRmax], and (c) HIIE 2 [10 × 1min at 80%-90% of HRmax − 1-min recovery]. Then, VO2 and fat utilization measured at rest and during the 2 hours post-exercise, enjoyment, perceived exertion, and appetite recorded during the session and energy intake (EI) and energy expenditure (EE) assessed over the next 24 hours were compared for the three modalities. Overall, fat utilization increased after exercise. No modality effect or time-modality interaction was observed concerning VO2 and fat oxidation rate during the 2 hours post-exercise. The two exercise modalities did not induce specific EI and EE adaptations, but perceived appetite scores at 1 hour post-exercise were lower after HIIE 1 and HIIE 2 than MICE. Perceived exertion was higher during HIIE 1 and HIIE 2 than MICE, but enjoyment did not differ among modalities. The acute HIIE responses did not allow explaining the greater fat mass loss observed after regular high-intensity interval training in post-menopausal women with overweight/obesity. More studies are needed to understand the mechanisms involved in such adaptations.  相似文献   
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小儿淋巴管瘤的MRI诊断   总被引:7,自引:0,他引:7  
目的分析小儿淋巴管瘤的磁共振表现及其病理基础。方法对6例经手术病理证实的、年龄7天至7岁的小儿淋巴管瘤患者的磁共振表现进行回顾性分析。结果淋巴管瘤磁共振表现为T1WI上呈与肌肉相似或稍高的信号,T2WI上高于脂肪信号。5例瘤内可见低信号分隔,1例瘤内见血管流空影,3例见明显包膜,3例边界不清。2例病理诊断为海绵状淋巴管瘤,4例诊断为囊状淋巴管瘤。结论磁共振成像可较好地显示肿瘤的大小、形态及范围,从而指导手术治疗。  相似文献   
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Background Subcutaneous zygomycosis is an uncommon condition observed in tropics. Few series have been published, particularly from the northern regions of India. Objectives The aim of this study was to describe clinical, investigative and therapeutic details in subcutaneous zygomycosis observed in two teaching hospitals in Delhi. Patients and methods Ten patients seen over a period of 10 years (1999–2009) form the material for this report. Results There were four children and six adults. In four children, the presentation was a subcutaneous localized mass or gradually spreading plaque. In the others, it was observed over nasal region of face, spreading inward into mucosal sites and paranasal sinuses, and outward to the contiguous areas. Regional lymphadenopathy was present in two with facial lesions. Majority showed a granulomatous infiltrate with admixture of other cells, mainly eosinophils. Aseptate or poorly septate hyphae were observed in seven. In one patient in whom no hyphae were observed, there was dense perivascular inflammation. Organisms were cultured from four patients, Basidiobolus ranarum in two and Syncephalastrum racemosum in two. The main therapy used was a saturated solution of potassium iodide (KI). Four received only KI of which two attained cure after 3 months and 9 months respectively, and the other two showed signs of regression. In one boy subsidence was associated with reduced circumference of thigh. Ketoconazole or itraconazole was given with KI to hasten regression when response was slow or there were side‐effects to KI. Conclusion Awareness and early recognition will prevent disfigurement produced by advanced disease, misdiagnosis and unnecessary surgical intervention.  相似文献   
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INTRODUCTION: The objectives of this paper are to review the environmental factors, the different erythrocyte ligands and the corresponding endothelial receptors involved in adhesion. CURRENT KNOWLEDGE AND KEY POINTS: Leukocyte adhesion to vascular endothelium is related to inflammation and has been widely studied. The adhesion of erythrocytes to vascular endothelium has been investigated more recently, mainly in the physiopathology of three diseases: diabetes mellitus, sickle cell disease and malaria. The three diseases are characterized by microvascular complications and are deleterious for the red blood cell membrane. They lead to abnormal erythrocyte adhesion to vascular endothelium. Thus better understanding of the mechanisms involved in red blood cell adhesion to the endothelium is important since it might lead to the development of new therapeutic targets. Progress in this field might contribute to therapeutic improvement in sickle cell disease and to the development of an antimalarial vaccine. FUTURE PROSPECTS AND PROJECTS: However, additional studies focusing on in vivo endothelium heterogeneity, the different subpopulations of red blood cells and the diversity of Plasmodium falciparum strains are required. The consequences of such erythrocytes/endothelium interactions on the endothelial functions remain to be established.  相似文献   
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