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661.
Purpose. Changes in retinal vascular caliber measured from digital color fundus photographs have been independently associated with systemic outcomes in epidemiologic studies, but the effect of image resolution and compression on vascular measurements has not been previously evaluated. Methods. To explore image compression, 40 natively digital fundus images were selected with good photo quality, high spatial resolution, and no previous image compression. Using Adobe Photoshop, these images were compressed at progressively higher levels up to 147:1, and then retinal vascular caliber was measured at each level using semiautomated software. To examine resolution, 40 fundus photographs acquired on high-resolution film were scanned with settings corresponding to 10, 7, 5, 3, and 1 megapixel fundus cameras. After adjusting for scale factor, vascular caliber was measured at each level of resolution. Data were analyzed by comparing the calculated central retinal arteriole equivalent (CRAE) and the central retinal venular equivalent (CRVE) of the original and altered images, using repeated measures ANOVA. Results. CRAE became significantly wider with increasing levels of compression at the 25:1 threshold (~1 μm wider, P < 0.001) and was ~5 μm wider with 147:1 compression. CRVE also increased, but less than CRAE. Using 7 (megapixel)-MP resolution as the standard, CRVE was significantly narrower at the 5-MP simulation (~2 μm, P < 0.001) and was ~12 μm narrower at the 1-MP simulation. CRAE also decreased, but less than CRVE. Conclusions. Increasing digital image file compression and decreasing fundus image spatial resolution led to skewed measurements of the retinal vascular caliber.  相似文献   
662.
This prospective study reports significant hypoglycaemic and hypolipidaemic effects in type 2 diabetic subjects who were provided the complete diet plan to be on low glycaemic index (GI) and low-medium glycaemic load (GL) Indian vegetarian snacks and mixed meals for 4 continuous weeks. Five millilitres of fasting blood sample drawn at weekly intervals for 4 weeks were analysed for blood glucose, HbA1c and lipid profile. Four weeks later mean blood glucose level of 173.6?mg% decreased to 137.8?mg%, HbA1c of 8% also decreased to 7.1% which reflected the blood glucose level during the study period and hence correlated well with the fall in blood glucose level. Triglyceride level of 244.5?mg% decreased to 164.7?mg% (p?相似文献   
663.

Objectives

To determine how grant funds are shared between academic institutions and community partners in community‐based participatory research (CBPR).

Methods

Review of all 62 investigator‐initiated R01 CBPR grants funded by the National Institutes of Health from January 2005 to August 2012. Using prespecified criteria, two reviewers independently categorized each budget item as being for an academic institution or a community partner. A third reviewer helped resolve any discrepancies.

Results

Among 49 evaluable grants, 68% of all grant funds were for academic institutions and 30% were for community partners. For 2% of funds, it was unclear whether they were for academic institutions or for community partners. Community partners’ share of funds was highest in the categories of other direct costs (62%) and other personnel (48%) and lowest in the categories of equipment (1%) and indirect costs (7%).

Conclusions

A majority of CBPR grant funds are allocated to academic institutions. In order to enhance the share that community partners receive, funders may wish to specify a minimum proportion of grant funds that should be allocated to community partners in CBPR projects.  相似文献   
664.
Although annual breast magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer as an adjunct to screening mammography, breast MRI use remains low. We examined factors associated with breast MRI use in a cohort of women with a family history of breast cancer but no personal cancer history. Study participants came from the Sister Study cohort, a nationwide, prospective study of women with at least 1 sister who had been diagnosed with breast cancer but who themselves had not ever had breast cancer (n = 17 894). Participants were surveyed on breast cancer beliefs, cancer worry, breast MRI use, provider communication, and genetic counseling and testing. Logistic regression was used to assess factors associated with having a breast MRI overall and for those at high risk. Breast MRI was reported by 16.1% and was more common among younger women and those with higher incomes. After adjustment for demographics, ever use of breast MRI was associated with actual and perceived risk. Odds ratios (OR) were 12.29 (95% CI, 8.85‐17.06), 2.48 (95% CI, 2.27‐2.71), and 2.50 (95% CI, 2.09‐2.99) for positive BRCA1/2 test, lifetime breast cancer risk ≥ 20%, and being told by a health care provider of higher risk, respectively. Women who believed they had much higher risk than others or had higher level of worry were twice as likely to have had breast MRI; OR = 2.23 (95% CI, 1.82‐2.75) and OR = 1.76 (95% CI, 1.52‐2.04). Patterns were similar among women at high risk. Breast cancer risk, provider communication, and personal beliefs were determinants of breast MRI use. To support shared decisions about the use of breast MRI, women could benefit from improved understanding of the chances of getting breast cancer and increased quality of provider communications.  相似文献   
665.
666.
667.

Objective  

To assess the iodine status among primary school children of Dhankuta and Dharan in eastern Nepal.  相似文献   
668.

Objective

To develop and validate a detector that identifies ripple (80–200?Hz) events in intracranial EEG (iEEG) recordings in a referential montage and utilizes independent component analysis (ICA) to eliminate or reduce high-frequency artifact contamination. Also, investigate the correspondence of detected ripples and the seizure onset zone (SOZ).

Methods

iEEG recordings from 16 patients were first band-pass filtered (80–600?Hz) and Infomax ICA was next applied to derive the first independent component (IC1). IC1 was subsequently pruned, and an artifact index was derived to reduce the identification of high-frequency events introduced by the reference electrode signal. A Hilbert detector identified ripple events in the processed iEEG recordings using amplitude and duration criteria. The identified ripple events were further classified and characterized as true or false ripple on spikes, or ripples on oscillations by utilizing a topographical analysis to their time-frequency plot, and confirmed by visual inspection.

Results

The signal to noise ratio was improved by pruning IC1. The precision of the detector for ripple events was 91.27?±?4.3%, and the sensitivity of the detector was 79.4?±?3.0% (N?=?16 patients, 5842 ripple events). The sensitivity and precision of the detector was equivalent in iEEG recordings obtained during sleep or intra-operatively. Across all the patients, true ripple on spike rates and also the rates of false ripple on spikes, that were generated due to filter ringing, classified the seizure onset zone (SOZ) with an area under the receiver operating curve (AUROC) of >76%. The magnitude and spectral content of true ripple on spikes generated in the SOZ was distinct as compared with the ripples generated in the NSOZ (p?<?.001).

Conclusions

Utilizing ICA to analyze iEEG recordings in referential montage provides many benefits to the study of high-frequency oscillations. The ripple rates and properties defined using this approach may accurately delineate the seizure onset zone.

Significance

Strategies to improve the spatial resolution of intracranial EEG and reduce artifact can help improve the clinical utility of HFO biomarkers.  相似文献   
669.
670.
How responsive neurostimulation (RNS) decreases seizure frequency is unclear. Stimulation may alter epileptic networks during inter-ictal epochs. Definitions of the epileptic network vary but fast ripples (FRs) may be an important substrate. We, therefore, examined whether stimulation of FR-generating networks differed in RNS super responders and intermediate responders. In 10 patients, with subsequent RNS placement, we detected FRs from stereo-electroencephalography (SEEG) contacts during pre-surgical evaluation. The normalized coordinates of the SEEG contacts were compared with those of the eight RNS contacts, and RNS-stimulated SEEG contacts were defined as those within 1.5 cm3 of the RNS contacts. We compared the post-RNS placement seizure outcome to (1) the ratio of stimulated SEEG contacts in the seizure-onset zone (SOZ stimulation ratio [SR]); (2) the ratio of FR events on stimulated contacts (FR SR); and (3) the global efficiency of the FR temporal correlational network on stimulated contacts (FR SGe). We found that the SOZ SR (p = .18) and FR SR (p = .06) did not differ in the RNS super responders and intermediate responders, but the FR SGe did (p = .02). In super responders, highly active desynchronous sites of the FR network were stimulated. RNS that better targets FR networks, as compared to the SOZ, may reduce epileptogenicity more.  相似文献   
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