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41.
Purpose:National Accreditation Board for Hospitals and Healthcare Providers operates the health-care accreditation program in India. Research on impact of accreditation on eye-care centers is scarce. This article was conceptualized to scientifically evaluate the changes in documentation brought about by accreditation and its effects on staff in the Ophthalmology Department of an Indian Medical College.Methods:This was conducted as a quasi-experimental study in four steps. First, a point-based evaluation of case sheets in both pre-accreditation and postaccreditation phase, along with statistical analysis of the results, was done. Step two involved analysis of quality indicators and patient safety indices in successive years from inception of data to post-accreditation phase. Step three comprised a survey of staff employing a validated tool, and finally, face-to-face semistructured interviews with designated authorities, including finance departmental head, completed the study.Results:A statistically significant difference was seen in scores achieved by the pre and postaccreditation case sheets, with the postphase case sheets achieving 15% increased scores over the prephase case sheets. Quality indicator indices displayed improvements post-accreditation. There was an accompanying increase in quantity of documentation. Financial data analysis showed increased expenditure for accreditation under multiple heads. Staff believed that accreditation led to increased workload but did not express decreased satisfaction and felt that accreditation was eventually beneficial. However, staff believed rewards for improving quality can be enhanced.Conclusion:Accreditation increases quality and quantity of documentation, and staff workload. Increased financial costs also ensue.Staff believe that accreditation improves quality, is beneficial, but desire enhanced rewards.  相似文献   
42.

Introduction

Anterior cervical decompression and fusion is a well-established procedure for treatment of degenerative disc disease and cervical trauma including flexion-distraction injuries. Low-profile interbody devices incorporating fixation have been introduced to avoid potential issues associated with dissection and traditional instrumentation. While these devices have been assessed in traditional models, they have not been evaluated in the setting of traumatic spine injury. This study investigated the ability of these devices to stabilize the subaxial cervical spine in the presence of flexion-distraction injuries of increasing severity.

Methods

Thirteen human cadaveric subaxial cervical spines (C3–C7) were tested at C5–C6 in flexion–extension, lateral bending and axial rotation in the load-control mode under ±1.5 Nm moments. Six spines were tested with locked screw configuration and seven with variable angle screw configuration. After testing the range of motion (ROM) with implanted device, progressive posterior destabilization was performed in 3 stages at C5–C6.

Results

The anchored spacer device with locked screw configuration significantly reduced C5–C6 flexion–extension (FE) motion from 14.8 ± 4.2 to 3.9 ± 1.8°, lateral bending (LB) from 10.3 ± 2.0 to 1.6 ± 0.8, and axial rotation (AR) from 11.0 ± 2.4 to 2.5 ± 0.8 compared with intact under (p < 0.01). The anchored spacer device with variable angle screw configuration also significantly reduced C5–C6 FE motion from 10.7 ± 1.7 to 5.5 ± 2.5°, LB from 8.3 ± 1.4 to 2.7 ± 1.0, and AR from 8.8 ± 2.7 to 4.6 ± 1.3 compared with intact (p < 0.01). The ROM of the C5–C6 segment with locked screw configuration and grade-3 F-D injury was significantly reduced from intact, with residual motions of 5.1 ± 2.1 in FE, 2.0 ± 1.1 in LB, and 3.3 ± 1.4 in AR. Conversely, the ROM of the C5–C6 segment with variable-angle screw configuration and grade-3 F-D injury was not significantly reduced from intact, with residual motions of 8.7 ± 4.5 in FE, 5.0 ± 1.6 in LB, and 9.5 ± 4.6 in AR.

Conclusions

The locked screw spacer showed significantly reduced motion compared with the intact spine even in the setting of progressive flexion-distraction injury. The variable angle screw spacer did not sufficiently stabilize flexion–distraction injuries. The resulting motion for both constructs was higher than that reported in previous studies using traditional plating. Locked screw spacers may be utilized with additional external immobilization while variable angle screw spacers should not be used in patients with flexion-distraction injuries.  相似文献   
43.
A retrospective analysis of endovenous glue-closure therapy (EVGC) performed in 76 greater saphenous veins (GSVs) from February 2016 to December 2017 was conducted to assess the incidence and characteristics of endovenous glue-induced thrombosis (EGIT), a phenomenon unique to nonthermal EVGC for GSV insufficiency. Kabnick and Lawrence classifications for endovenous heat-induced thrombosis were adopted. Seven instances of EGIT were detected among 54 patients (13%), with median/mode Kabnick and Lawrence classifications of 2/2 and 4/5, respectively. EGIT resolved with observation within an average of 5.2 wk after detection (range, 2–8 wk) without deep vein thrombosis or pulmonary embolism. EGIT was associated with significantly greater mean age (+7.75 y; P = .0308).  相似文献   
44.

Background

There is a paucity of data demonstrating the effect race and insurance status have on postoperative outcomes for patients with rectal cancer. We evaluated factors impacting short-term outcomes following rectal cancer surgery.

Design

Patients who underwent surgery for rectal cancer using the University Health System Consortium database from 2011 to 2012 were studied. Univariate and multivariable analyses were used to identify patient related risk factors for 30-day outcomes after proctectomy: complication rate, 30-day readmission, ICU stay, and length of hospital stay (LOS).

Results

A total of 9272 proctectomies were identified in this cohort. After adjustment for potential confounders, black patients were more likely to have 30-day readmissions (OR 1.51, 95 % CI 1.26–1.81), ICU stays (OR 1.25, 95 % CI 1.03–1.51), and longer LOS (+1.67 days, 95 % CI 1.21–2.13) when compared to whites. Compared to those with private insurance, patients with public or military insurance or who were self-pay had a higher likelihood of having postoperative complications.

Conclusions

In patients who undergo elective proctectomy for rectal cancer, non-white and non-privately insured status are associated with significantly worse short-term outcomes. Further studies are needed to determine the implications with respect to receipt of adjuvant therapy and survival.
  相似文献   
45.
Li B  Avinash GB  Hsieh J 《Medical physics》2007,34(10):3732-3738
Until recently, most studies addressing the trade-off between spatial resolution and quantum noise were performed in the context of single-slice CT. In this study, we extend the theoretical framework of previous works to volumetric CT and further extend it by taking into account the actual shapes of the preferred reconstruction kernels. In the experimental study, we also attempt to explore a three-dimensional approach for spatial resolution measurement, as opposed to the conventional two-dimensional approaches that were widely adopted in previously published studies. By scanning a finite-sized sphere phantom, the MTF was measured from the edge profile along the spherical surface. Cases of different resolutions (and noise levels) were generated by adjusting the reconstruction kernel. To reduce bias, the total photon fluxes were matched: 120 kVp, 200 mA, and 1 s per gantry rotation. All data sets were reconstructed using a modified FDK algorithm under the same condition: Scan field-of-view (SFOV) = 10 cm, and slice thickness = 0.625 mm. The theoretical analysis indicated that the variance of noise is proportional to > 4th power of the spatial resolution. Our experimental results supported this conclusion by showing the relationship is 4.6th (helical) or 5th (axial) power.  相似文献   
46.
Efficient delivery of viruses, proteins and biological macromelecules into a micrometer-sized focal spot of an XFEL beam for coherent diffraction imaging inspired new development in touch-free particle injection methods in gaseous and vacuum environments. This paper lays out our ongoing effort in constructing an all-optical particle delivery approach that uses piconewton photophoretic and femtonewton light-pressure forces to control particle delivery into the XFEL beam. We combine a spatial light modulator (SLM) and an electrically tunable lens (ETL) to construct a variable-divergence vortex beam providing dynamic and stable positioning of levitated micrometer-size particles, under normal atmospheric pressure. A sensorless wavefront correction approach is used to reduce optical aberrations to generate a high quality vortex beam for particle manipulation. As a proof of concept, stable manipulation of optically-controlled axial motion of trapped particles is demonstrated with a response time of 100ms. In addition, modulation of trapping intensity provides a measure of the mass of a single, isolated particle. The driving signal of this oscillatory motion can potentially be phase-locked to an external timing signal enabling synchronization of particle delivery into the x-ray focus with XFEL pulse train.OCIS codes: (140.7010) Laser trapping, (350.4855) Optical tweezers or optical manipulation  相似文献   
47.
We report a rare case of a 44-year-old male who underwent a diagnostic coronary angiogram following a non-ST elevation myocardial infarction complicated by an aortic valve leaflet tear requiring surgical intervention. Routine transthoracic echocardiogram demonstrated a mobile echogenic structure prolapsing into the left ventricular outflow tract. An intraoperative transesophageal echocardiogram confirmed that the structure originated from the ventricular side of left coronary cusp, causing malcoaptation between left and right coronary cusps, and subsequent moderate to severe aortic regurgitation.  相似文献   
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OBJECTIVE: To assess the efficacy and toxicity of moricizine in treating patients with serious ventricular arrhythmias and inducible sustained ventricular tachycardia. DESIGN: Uncontrolled clinical trial. SETTING: The intensive care and telemetry units of Northwestern Memorial Hospital, St. Francis Hospital and Medical Center, and Lenox Hill Hospital. PATIENTS: Twenty-six patients with sustained ventricular arrhythmias or hemodynamically significant nonsustained ventricular tachycardia, most of whom failed therapy with at least one class I antiarrhythmic agent. INTERVENTION: Patients were treated with moricizine, 400 to 1000 mg/d. MEASUREMENT: Efficacy was assessed by the results of programmed ventricular stimulation done during moricizine therapy. MAIN RESULTS: Seven of the 26 patients (27%) developed life-threatening ventricular proarrhythmia during moricizine loading. Three patients had incessant sustained ventricular tachycardia, two had incessant nonsustained ventricular tachycardia, one had new sustained ventricular tachycardia, and one had new cardiac arrest. One of these patients died of intractable ventricular fibrillation. No clinical or electrophysiologic variables clearly identified those at risk for proarrhythmia. Only 3 of 26 patients (12%) became noninducible on moricizine. CONCLUSION: Moricizine has a low rate of efficacy and carries a considerable risk for life-threatening proarrhythmia in patients with serious ventricular arrhythmias and inducible ventricular tachycardia who have failed therapy with other class I antiarrhythmic agents.  相似文献   
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