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排序方式: 共有648条查询结果,搜索用时 15 毫秒
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Ashjaei S Miller WP Cabrera ML Hassan SM 《International journal of environmental research and public health》2011,8(5):1534-1546
In regions of concentrated poultry production, poultry litter (PL) that contains significant quantities of trace elements is commonly surface-applied to pastures at high levels over multiple years. This study examined the effect of long-term applications of PL on soil concentrations of arsenic (As), copper (Cu), Zinc (Zn), and the uptake of these elements by bermuda grass grown on Cecil (well-drained) and Sedgefield (somewhat poorly-drained) soils. The results showed that concentrations of As, Cu, and Zn in soils that had received surface-applied PL over a 14-year period were significantly greater than untreated soil at 0-2.5 and 2.5-7.5 cm depths. However, the levels were well below the USEPA loading limits established for municipal biosolids. Arsenic fractionation showed that concentrations of all As fractions were significantly greater in PL-amended soils compared to untreated soils at 0-2.5 and 2.5-7.5 cm depths. The residual fraction was the predominant form of As in all soils. The water-soluble and NaHCO(3)-associated As were only 2% of the total As. Significant differences were found in concentrations of these trace elements and phosphorus (P) in forage from PL-amended soils compared to that in untreated plots. The concentrations of Cu, Zn, As, and P were significantly greater in forage from Sedgefield amended soil compared to Cecil soil, but were in all cases below levels of environmental concern. 相似文献
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Azin Shayganfar Maryam Moradi Roshanak Moshiri Alireza Khosravi Shadi Ebrahimian 《Current problems in diagnostic radiology》2021,50(3):328-331
PurposeRenal Resistive Index (RRI) is a newly introduced sonographic index in predicting contrast-induced nephropathy (CIN) development. It has been suggested that RRI > 0.69 should be considered as a risk factor for CIN development. The present study aimed to calculate the predictive value of RRI using a cutoff point of 0.69.MethodsA total of 90 patients who were a candidate for coronary vessels angiography were enrolled in this study. Color Doppler ultrasonography was performed and RRI was measured. Patients were followed up for 48 hours after contrast media exposure for the CIN development. The diagnosis of CIN was based on a 25% relative rise or 0.5 mg/dL absolute rise in creatinine level. The predictive values of RRI were measured using 0.69 as a cutoff point.ResultsOut of 90 patients, CIN developed in 3 patients and 17 patients had preprocedural RRI > 0.69. Of 3 patients with CIN, 1 had RRI > 0.69. Using 0.69 as the cutoff point, the measured sensitivity and specificity of RRI were 33.3% and 83.9%, respectively.ConclusionsRRI > 0.69 is not a sensitive index in predicting the CIN development and cannot be used as an independent factor. 相似文献
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Shadi Sepehri Guillaume Poliquin Nora Alfattoh David Boyd Michael Mulvey Andrew Denisuik Sergio Fanella James Karlowsky Andrew Walkty 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2014,25(4):229-231
A case of osteomyelitis in an infant following a burn injury sustained in Pakistan caused by a GES-13-producing Pseudomonas aeruginosa (the first reported in Canada) and an OXA-48 producing Klebsiella pneumoniae is described. The present case serves to highlight the importance of international travel as a risk factor for infection with carbapenemase-producing bacteria and the challenges in the laboratory detection of these organisms. 相似文献
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Annasha Vyas Katherine Moran Joshua Livingston Savannah Gonzales Marlene Torres Ali Duffens Carina Mireles Romo Genevieve Mazza Briana Livingston Shadi Lahham John Christian Fox 《世界急诊医学杂志(英文)》2018,9(3):216
BACKGROUND: Maternal and infant mortality rates reported in rural Panama are greater than those in urban regions. Bocas del Toro is a region of Panama inhabited by indigenous people at greater risk for pregnancy-related complications and deaths due to geographic isolation and limited access to health care. Portable ultrasound training programs have recently been implemented in low-resource settings to increase access to diagnostic imaging. The goal of this study is to determine the feasibility of teaching first-year medical students the Rural Obstetrical Ultrasound Triage Exam (ROUTE) to help identify pathology in pregnant women of the Bocas del Toro region of Panama.METHODS: Eight first-year medical students completed ROUTE training sessions. After training, the students were compared to professional sonographers to evaluate their accuracy in performing the ROUTE. Students then performed the ROUTE in mobile clinics within Bocas del Toro. They enrolled women pregnant in their 2nd or 3rd trimesters and measured biparietal diameter, head circumference, amniotic fluid index, fetal lie and placental position. Any abnormal measurement would be further analyzed by the lead physician for a potential hospital referral.RESULTS: A total of 60 women were enrolled in the study. Four women were detected as having a possible high-risk pregnancy and thus referred to a hospital for further evaluation.CONCLUSION: Based on our data, first-year medical students with additional training can use the ROUTE to identify complications in pregnancy using ultrasound in rural Panama. Additional studies are required to determine the optimal amount of training required for proficiency. 相似文献
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Sean P. Denny William B. Minteer Reece T.H. Fenning Sahil Aggarwal Debora H. Lee Shella K. Raja Kaavya R. Raman Allison O. Farfel Priya A. Patel MarkLieber Megan E. Bernstein Shadi Lahham John C. Fox 《世界急诊医学杂志(英文)》2018,9(1):33
BACKGROUND: Diagnostic imaging is an integral aspect of care that is often insufficient, if not altogether absent, in rural and remote regions of low to middle income countries (LMICs) such as Tanzania. The introduction of ultrasound can significantly impact treatment in these countries due to its portability, low cost, safety, and usefulness in various medical assessments. This study reviews the implementation of a four-week ultrasound course administered annually from 2013-2016 in a healthcare professional school in Mwanza, Tanzania by first-year allopathic US medical students.METHODS: Participants (n=582, over 4 years) were recruited from the Tandabui Institute of Health Sciences and Technology to take the ultrasound course. Subjects were predominantly clinical officer students, but other participants included other healthcare professional students, practicing healthcare professionals, and school employees. Data collected includes pre-course examination scores, post-course examination scores, course quiz scores, demographic surveys, and post-course feedback surveys. Data was analyzed using two-tailed t-tests and the single factor analysis of variance (ANOVA).RESULTS: For all participants who completed both the pre- and post-course examinations (n=229, 39.1% of the total recruited), there was a significant mean improvement in their ultrasound knowledge of 42.5%, P<0.01.CONCLUSION: Our data suggests that trained first-year medical students can effectively teach a point of care ultrasound course to healthcare professional students within four weeks in Tanzania. Future investigation into the level of long-term knowledge retention, impact of ultrasound training on knowledge of human anatomy and diagnostic capabilities, and how expansion of an ultrasound curriculum has impacted access to care in rural Tanzania is warranted. 相似文献
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