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Reg B. Wilcox III PT DPT MS Joel Fallano PT DPT Kenneth J. Shannon PT DPT John A. Carrino MD MPH Jacquelyn Sinclair RPh MM Ramin Khorasani MD MPH 《Journal of digital imaging》2006,19(4):346-350
Imaging plays an increasing role in physical therapy (PT) practice. We sought to determine if picture archiving and communication
system (PACS) deployment would increase the proportion of imaging studies viewed by physical therapists (PTs) at the point
of care and to assess PTs' perception of the value of access to imaging information. The study was performed in a 720-bed
urban teaching hospital where an average of 2,000 rehabilitation visits per month are performed by 12 PTs. We compared the
proportion of imaging studies viewed by PTs before and after PACS implementation. We surveyed PTs to assess their perception
on the value of access to imaging studies. Film library records pre-PACS and web server audit trail post-PACS implementation
were reviewed to measure access. Chi-square was used to compare proportions and trends. During the 3-month period before PACS
usage, PTs viewed 1% (6/505) of imaging studies, citing time as the primary barrier. Post-PACS, the proportion of imaging
studies viewed rose from 28% (95/344, second month) to 84% (163/192, fifth month) (p < 0.0001, chi-square). Most PTs believed that access to imaging studies has high value and has a positive impact on clinical
practice. Physical therapists rarely viewed imaging studies before PACS due to time barriers. They viewed more imaging studies
(84%) post-PACS and felt that access to imaging studies has a positive impact on clinical practice. Further studies are needed
to assess whether PACS enhances PTs' clinical decision making and improves patient outcomes. 相似文献
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Ravindra Rajakariar Naina Jivanji Mira Varagunam Mohammad Rafiq Arun Gupta Michael Sheaff Paul Sinnott MM Yaqoob 《American journal of transplantation》2005,5(8):1922-1925
In renal transplantation, serum soluble CD30 (sCD30) levels in graft recipients are associated with increased rejection and graft loss. We investigated whether pre-transplant sCD30 concentrations are predictive of the grade of rejection. Pre-transplant sera of 51 patients with tubulointerstitial rejection (TIR), 16 patients with vascular rejection (VR) and an age-matched control group of 41 patients with no rejection (NR) were analyzed for sCD30. The transplant biopsies were immunostained for C4d. The median sCD30 level was significantly elevated in the group with VR (248 Units (U)/mL, range: 92-802) when compared with TIR (103 U/mL, range: 36-309, p<0.001) and NR (179 U/mL, range: 70-343, p<0.03). Moreover, patients with TIR had significantly lower sCD30 levels compared to NR. Based on C4d staining, a TH2 driven process, the median sCD30 levels were significantly raised in C4d+ patients compared with C4d- group (177 U/mL vs. 120 U/mL, p<0.05). sCD30 levels measured at time of transplantation correlate with the grade of rejection. High pre-transplant levels are associated with antibody-mediated rejection which carries a poorer prognosis. sCD30 could be another tool to assess immunological risk prior to transplantation and enable a patient centered approach to immunosuppression. 相似文献
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Optical imaging and electrophysiology of rat barrel cortex. II. Responses to paired-vibrissa deflections 总被引:1,自引:0,他引:1
A study was undertaken to investigate the response of the rodent
somatosensory barrel cortex to paired-whisker stimuli. Cortical responses
to controlled whisker deflections were recorded by (i) conventional
multi-unit extracellular recording within the cytochrome oxidase rich
barrels centers, and (ii) intrinsic signal optical imaging, a technique
that measures an optical correlate of neuronal activity thought to be
related to the deoxygenation of hemoglobin in activated regions. Stimuli
were applied to two whiskers in sequence, at temporal separations ranging
from 0 to 60 ms. Over intervals of 10-40 ms, the primary effect of
paired-whisker stimulation was suppressive. We suggest that paired-whisker
inhibition results from the activation of layer IV fast-spike units within
the principle whisker's barrel, by excitatory input arriving from a
surround-whisker. Paired-whisker stimulation produces inhibition in
intrinsic images, because it results in a net reduction in layer II/III
and/or layer IV metabolism. Intra- cortical inhibition may serve to convert
the sequence of inputs from the whisker array into a barrel cortex
magnitude code that can be read by higher cortical areas.
相似文献
1000.
Steven R. Fleagle Daniel R. Thedens William Stanford Roderic I. Pettigrew Nathaniel Reichek David J. Skorton 《Journal of magnetic resonance imaging : JMRI》1993,3(2):409-415
The purpose of the present study was to evaluate the robustness of a method of automated border detection in cardiac magnetic resonance (MR) imaging. Thirty-seven short-axis spin-echo cardiac images were acquired from three medical centers, each with its own image-acquisition protocol. Endo- and epicardial borders and areas were derived from these images with a graph-searching-based method of edge detection. Computer results were compared with observer-traced borders. The method accurately defined myocardial borders in 36 of 37 images (97%), with excellent agreement between computer- and observer-derived endocardial and epicardial areas (correlation coefficients,.94-.99). The algorithm worked equally well for data from all three centers, despite differences in image-acquisition protocols, MR systems, and field strengths. These data suggest that a method of computer-assisted edge detection based on graphsearching principles yields endocardial and epicardial areas that correlate well with those derived by an independent observer. 相似文献