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Exposure to air pollution affects pulmonary functions adversely. Effect of exposure to pollution on diurnal variation of peak flow was assessed in healthy students. Three hundred healthy age-matched nonsmoker students were studied. They were categorized into two groups on the basis of their residence: commuters and living on campus. Peak expiratory flow (PEF) recordings were made twice daily for 2 days with the Pink City Flow Meter. The measurement was then used to calculate for each subject the amplitude percentage mean, which is an index for expressing PEF variability for epidemiological purposes (Higgins BG, Britton JR, Chinns Jones TD, Jenkinson D, Burnery PG, Tattersfield AE. Distribution of peak expiratory flow variability in a population sample. Am Rev Respir Dis 1989; 140:1368-1372). Air pollution parameters were quantified by measurement of sulfur dioxide (SO2), oxides of nitrogen (NO2), carbon monoxide (CO), and respirable suspended particulate matter (RSPM) in the ambient air at the campus and on the roadside. The mean values of PEF variability (amplitude percent mean) in the students living on campus and in the commuters were 5.7 +/- 3.2 and 11 +/- 3.6, respectively (P < .05). Among the commuters, maximum number of subjects showed amplitude percentage mean PEFR at the higher end of variability distribution, as compared to the students living on campus, among whom the majority of subjects fell in the lower ranges of variability distribution. The ambient air quality parameters, namely SO2, NO2, CO, and RSPM were significantly lower on the campus. It can be concluded that long-term periodic exposure to air pollution can lead to increased PEF variability even in healthy subjects. Measurement of PEF variability may prove to be a simple test to measure effect of air pollution in healthy subjects. 相似文献
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A 12.5% corn oil-emulsion (COE) was tested as an oral contrast agent for abdominal computed tomography (CT) examinations in 100 patients. The results were compared with those obtained from another group of patients who received a conventional, high-density, oral contrast agent (2-3% iodinated solution). There was no statistically significant difference in the subjects' tolerance to the two agents (P greater than 0.05). There was, however, a significant improvement in image quality with COE (P less than 0.05). Gastrointestinal tract discrimination, and mucosal and mural visualisation was of higher quality with fat density oral contrast medium than with the high-density contrast agent. These data suggest that COE should be considered for routine use as an alternative to conventional high density oral contrast agents in upper abdominal CT. 相似文献
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The histamine metabolitetele-methylhistamine (t-MH) was identified and measured in crude and purified peritoneal mast cells (MCs). Peritoneal dialysates, peritoneal cells, and purified MCs all containedt-MH in concentrations representing about 0.2% of the corresponding histamine (HA) levels.T-MH levels in crude cells represented about 70% of the total dialysate levels, indicating the presence of extracellular as well as intracellulart-MH.T-MH levels per MC in purified fractions were similar to those of crude fractions, indicating a MC origin for the intracellulart-MH. Histamine methyltransferase activity was not detected in crude or purified MC fractions, and incubations with the monoamine oxidase inhibitor pargyline failed to increase the content or release oft-MH in either fraction, suggesting a very slow or non-existent histamine methylation in MCs. Compound 48/80 produced a temperature-dependent release of HA andt-MH in crude and purified preparations, and Triton X-100 also released both amines. In all cases, the degree of release of both amines was correlated, consistent with a granular origin fort-MH in MCs. The low concentrations oft-MH in MCs do not necessarily indicate a role for MCs in HA metabolism, but suggest thatt-MH may be a valuable marker for non-MC HA. 相似文献
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Jordana Laks Christine Khandelwal Eleni Footman Margaret Jamison Ellen Roberts 《Teaching and learning in medicine》2016,28(2):210-218
Problem: Medical students have limited exposure to Geriatrics in their traditional training. Service-learning offers students the opportunity to engage with older adult communities and become more comfortable interacting with this population. Intervention: A preclinical elective course was developed to expand medical students' experiences in Geriatrics through service-learning. In this course, students conducted needs assessments in diverse older adult communities, created health education projects to address community-identified needs, and reflected on their experiences through written assignments and presentations. The course instructor presented lectures on special topics in Geriatrics, including ageism and health literacy. The curriculum aimed to familiarize students with older adults' needs in a variety of settings. Context: Over 3 years, 74 students participated in the service-learning course. Students were assigned to older adult community sites, where they conducted needs assessments and designed and implemented original educational projects targeting community concerns. Program evaluation methods included a validated survey assessing students' attitudes toward older adults, course evaluations, review of student assignments and projects, and feedback from older adult participants and site coordinators. Outcome: Students gained hands-on experience working with older adults and designing appropriate health education projects. Analysis of attitude surveys demonstrated students' increased interest in Geriatrics as a career. Both students and older adult participants described enjoyable, valuable experiences gained from service-learning activities. Lessons Learned: Students appreciated the combination of community and classroom learning about Geriatrics. Service-learning was most constructive at sites with responsive coordinators, engaged older adults, and a need for health education resources. The course challenged students to assess health needs in communities that included cognitively impaired elders and to design educational projects tailored to older adults. 相似文献
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Kushaljit Singh Sodhi Akshay Kumar Saxena Niranjan Khandelwal Y. K. Chawla 《The Indian journal of surgery》2014,76(5):413-414
Pseudolipoma of inferior vena cava refers to a normal variant of adipose collection that is seen in typical pericaval or juxtacaval location; however, it mimics an intracaval mass lesion, especially fat-containing lesions such as lipoma. Awareness of this entity is very important to avoid misdiagnosis and unnecessary diagnostic procedures. 相似文献
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