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71.
Background and Aims: Dyspnea may signal serious disease with increased morbidity/mortality. Dyspnea screening would only be valid if reproducible. The study aim was to determine the reliability (reproducibility) of assessing dyspnea through a simple questionnaire among a rural population. Methods: Participants were recruited from a Health Effects of Arsenic Longitudinal Study in Araihazar, Bangladesh. Dyspnea assessment used a questionnaire among 129 participants at two time points: at baseline and after 2 weeks to 9 months by trained physicians. All subjects were asked about the presence/absence of dyspnea in the last 6 months. At the second interview, a physician (blinded to questionnaire) conducted a clinical heart/lung examination and obtained a pulse oximeter reading. Results: Dyspnea prevalence by baseline questionnaire was 2.4%. Overall dyspnea reliability was 94% (121 out of 129). If the initial response was ‘yes’ for the presence of dyspnea, reliability was 91% (49 out of 54). For an initial response of ‘no’ for the presence of dyspnea, reliability was 96% (72 out of 75). The pulmonary examination and pulse oximeter readings were significantly more likely to be abnormal in those with dyspnea (P < 0.01). Conclusions: The reliability of a simple question on dyspnea is very high when obtained by physicians. Although validity was not the primary outcome, the increased likelihood of an abnormal chest examination or low pulse oximeter saturation for those reporting ‘yes’ to the dyspnea question suggests more significant underlying cardiopulmonary disease in those reporting recent dyspnea. Please cite this paper as: Pesola GR, Parvez F, Jasmin S, Hasan AKM R and Ahsan H. Dyspnea reproducibility in a rural Bangladesh population. The Clinical Respiratory Journal 2009; 3: 222–228.  相似文献   
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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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The authors report an 8-year-old girl with refractory status epilepticus due to hypertensive encephalopathy, secondary to end-stage renal disease. Brain magnetic resonance imaging (MRI) in the acute phase showed striking hyperintensities in the brain stem and medial thalamus along with subtle cortical lesions. After successful control of hypertensive crisis and status epilepticus, the patient recovered to her baseline. Near total resolution of the lesions was noted on follow-up imaging performed 9 days later. Predominant brainstem involvement as a feature of posterior reversible encephalopathy syndrome due to hypertensive crisis is extremely rare in children and has not been well documented.  相似文献   
75.
一体化PET/MR检查护理规范是关于PET/MR检查过程中对于护理人员的工作要求,包括检查前准备、注射药物护理、检查时护理、检查后护理、对比剂不良反应处理和个人辐射防护。旨在为核医学科护士在临床PET/MR检查中提供实用且行之有效的处理操作规范。  相似文献   
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Bone marrow imaging: magnetic resonance studies related to age and sex   总被引:9,自引:0,他引:9  
Measurements of T1 and T2 relaxation values and spin density of the lumbar vertebral bone marrow were performed in 212 patients, and the results were correlated with the patients' age and sex. T1 and T2 relaxation times for bone marrow in the lumbar vertebral bodies showed a progressive decrease with age for both sexes (except for the T2 relaxation values in female patients). The replacement of hematopoietic marrow by fatty marrow could explain the decrease in T1 and T2. The T1 and T2 values were in the same range for the first two age groups (age 1-10 years and age 21-40 years) and became slightly greater for the older female patients (age 51 years and older) than for the older males. This could be due to the loss of bone and mineral content, which is more rapid and significant for women. These normal T1 and T2 values may provide a baseline for future evaluation of diseases involving the lumbar spine.  相似文献   
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Oral delivery of proteins: progress and prognostication   总被引:1,自引:0,他引:1  
The delivery of proteins has gained momentum with the development of biotechnology sector that provided large-scale availability of therapeutic proteins. The availability is mostly due to the advances in recombinant DNA technology. The low oral bioavailability, however, continues to be a problem for several proteins because of their large molecular size, low permeation through biological membranes, and susceptibility to molecular changes in both biological and physical environments. The demand for effective delivery of proteins by the oral route has brought a tremendous thrust in recent years both in the scope and complexity of drug delivery technology. The important therapeutic proteins and peptides being explored for oral delivery include insulin, calcitonin, interferons, human growth hormone, glucagons, gonadotropin-releasing hormones, enkephalins, vaccines, enzymes, hormone analogs, and enzyme inhibitors. This article reviews the progress in oral delivery of these proteins, provides comments on the strategies to improve their oral bioavailability, and highlights their current market trends.  相似文献   
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