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排序方式: 共有10000条查询结果,搜索用时 208 毫秒
931.
Ivan M. Rosado-Mendez Mark L. Palmeri Lindsey C. Drehfal Quinton W. Guerrero Heather Simmons Helen Feltovich Timothy J. Hall 《Ultrasound in medicine & biology》2017,43(4):790-803
Shear wave elasticity imaging has shown promise in evaluation of the pregnant cervix. Changes in shear wave group velocity have been attributed exclusively to changes in stiffness. This assumes homogeneity within the region of interest and purely elastic tissue behavior. However, the cervix is structurally/microstructurally heterogeneous and viscoelastic. We therefore developed strategies to investigate these complex tissue properties. Shear wave elasticity imaging was performed ex vivo on 14 unripened and 13 misoprostol-ripened cervix specimens from rhesus macaques. After tests of significant and uniform shear wave displacement, as well as reliability of estimates, group velocity decreased significantly from the distal (vaginal) to proximal (uterine) end of unripened, but not ripened, specimens. Viscosity was quantified by the slope of the phase velocity versus frequency. Dispersion was observed in both groups (median: 5.5 m/s/kHz, interquartile range: 1.5–12.0 m/s/kHz), also decreasing toward the proximal cervix. This work suggests that comprehensive assessment of complex tissues such as cervix requires consideration of structural heterogeneity and viscosity. 相似文献
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Amanda Haboush Tara Phebus Denise Tanata Ashby Helen Zaikina-Montgomery Kimberly Kindig 《Journal of community health》2011,36(1):111-120
The goal of the this study was to track and assess children’s health status in Nevada and build relationships between researchers
and school districts through the collection of mutually beneficial health data at a local level. All elementary schools in
Nevada were sent a health survey for parents of kindergarten students to complete. A total of 3,628 surveys were received
with usable height and weight needed to calculate Body Mass Index (BMI). African American and Hispanic children had significantly
higher BMI scores compared to Caucasian and Asian/Pacific Islander children, regardless of income. Children who had diabetes
or mental health concerns also had significantly higher mean BMIs compared to children without these health concerns. Overall
staff within the school districts felt that this surveillance system should be continued as data from this study provided
important information subsequently used to guide programming and when applying for grants. Our children’s welfare depends
on community collaboration to create and implement data-driven initiatives to combat childhood obesity. 相似文献
935.
Poonam R. Bajaj Kanishka Bhunia Leslie Kleiner Helen S. Joyner Denise Smith Girish Ganjyal 《Journal of microencapsulation》2017,34(2):218-230
Unhydrolysed pea protein (UN) forms very viscous emulsions when used at higher concentrations. To overcome this, UN was hydrolysed using enzymes alcalase, flavourzyme, neutrase, alcalase–flavourzyme, and neutrase–flavourzyme at 50?°C for 0?min, 30?min, 60?min, and 120?min to form hydrolysed proteins A, F, N, AF, and NF, respectively. All hydrolysed proteins had lower apparent viscosity and higher solubility than UN. Foaming capacity of A was the highest, followed by NF, N, and AF. Hydrolysed proteins N60, A60, NF60, and AF60 were prepared by hydrolysing UN for 60?min and used further for microencapsulation. At 20% oil loading (on a total solid basis), the encapsulated powder N60 had the highest microencapsulation efficiency (ME?=?56.2). A decrease in ME occurred as oil loading increased to 40%. To improve the ME of N60, >90%, UN and maltodextrin were added. Flowability and particle size distribution of microencapsulated powders with >90% microencapsulation efficiency and morphology of all powders were investigated. This study identified a new way to improve pea protein functionality in emulsions, as well as a new application of hydrolysed pea protein as wall material for microencapsulation. 相似文献
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Paul D. Robinson Rukshana C. Shroff Helen Spencer 《Pediatric nephrology (Berlin, Germany)》2013,28(3):375-386
As survival improves after lung and heart-lung transplants, the long term detrimental impact of current management on renal function becomes more apparent as the number of non-renal solid organ transplant recipients on renal transplant waiting lists increases. Progressive chronic kidney disease (CKD) is a significant cause of morbidity and mortality in the transplant population. In this review we discuss the specific problems prior to lung or heart-lung transplant that predispose to CKD, as well as potential renal complications encountered during the peri- and post-transplant period. Significant acute and chronic nephrotoxicity is caused by calcineurin inhibitors (CNI). Mechanisms to decrease CNI exposure exist but have yet to be adopted in routine clinical care. Modifiable risk factors and the current screening and management approach taken at our institution are described. Pediatric nephrologists should be involved from an early stage. Future work will need to focus on identifying more accurate measures of renal function, given the limitations of current glomerular filtration rate estimation equations in a population where nutritional status may rapidly change post transplant. Multicentre studies of CNI minimisation strategies are required to guide future therapy that aims to minimise CKD development and progression in this vulnerable population. 相似文献
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