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101.
目的:以四川省自贡市富顺县为例,探究乡镇卫生院急救服务能力状况,并以农药中毒的急救为例,了解急救点空间可及性。方法:在富顺县城集中26所乡镇卫生院负责人,采用自编问卷了解急救服务相关情况;收集行政区划、水系路网、人口分布、急救点位置等数据,基于GIS软件平台运用行进成本法定量测量急救点空间可及性。结果:富顺县能够开展指定抢救项目的医院所占比例较低;农药中毒急救点平均可达时间为13.57分钟,可达性较差的地区主要分布在富顺县西南边界。结论:富顺县乡镇卫生院急救资源软硬件水平均较低,乡级急救网络亟待健全;提高急救点空间可及性可考虑在县域西南边界增加急救点数量或加强路网建设;利用GIS技术评价急救点空间可及性直观易懂、具有可操作性。  相似文献   
102.

Introduction

Daytime sleepiness is highly prevalent in the general adult population and has been linked to an increased risk of workplace and vehicle accidents, lower professional performance and poorer health. Despite the established relationship between noise and daytime sleepiness, little research has explored the individual-level spatial distribution of noise-related sleep disturbances. We assessed the spatial dependence of daytime sleepiness and tested whether clusters of individuals exhibiting higher daytime sleepiness were characterized by higher nocturnal noise levels than other clusters.

Design and Methods

Population-based cross-sectional study, in the city of Lausanne, Switzerland.Sleepiness was measured using the Epworth Sleepiness Scale (ESS) for 3697 georeferenced individuals from the CoLaus|PsyCoLaus cohort (period?=?2009–2012). We used the sonBASE georeferenced database produced by the Swiss Federal Office for the Environment to characterize nighttime road traffic noise exposure throughout the city. We used the GeoDa software program to calculate the Getis-Ord Gi* statistics for unadjusted and adjusted ESS in order to detect spatial clusters of high and low ESS values. Modeled nighttime noise exposure from road and rail traffic was compared across ESS clusters.

Results

Daytime sleepiness was not randomly distributed and showed a significant spatial dependence. The median nighttime traffic noise exposure was significantly different across the three ESS Getis cluster classes (p?<?0.001). The mean nighttime noise exposure in the high ESS cluster class was 47.6, dB(A) 5.2?dB(A) higher than in low clusters (p?<?0.001) and 2.1?dB(A) higher than in the neutral class (p?<?0.001). These associations were independent of major potential confounders including body mass index and neighborhood income level.

Conclusions

Clusters of higher daytime sleepiness in adults are associated with higher median nighttime noise levels. The identification of these clusters can guide tailored public health interventions.  相似文献   
103.
The optimal combination of region-of-interest (ROI) size and strain length (SL) allowing two-segment strain and strain rate analyses in term neonates was investigated. The impact of different ROI sizes and SLs on the strain and strain rate beat-to-beat variation (BBV) was assessed in 80 good-quality tissue velocity images. Both BBVs decreased with increased ROI length and with increased SL (p < 0.05). There were no significant differences in the BBVs for ROI width 2, 3 and 4 mm (p > 0.05). Among the combinations eligible for two segment analysis, the lowest BBVs were found using SL 10 mm, ROI length 1 mm and ROI width 3 mm. Using this combination, the mean difference between the single-cycle value and two-cycle compound value for peak systolic strain rate was 6.2%, peak systolic strain was 2.9% and end systolic strain was 3.2% of the two-cycle compound mean values. Hence, strain and strain rate measurement in tissue velocity images in neonates is feasible and reliable.  相似文献   
104.
计算机X线摄影系统在床边胸部X线摄影中的应用价值   总被引:8,自引:0,他引:8  
目的 通过对CR系统在床边胸部X线摄影中若干技术要素的研究 ,提高床边X线胸片质量。方法 ①设置最佳的床边胸部曝光条件表和影像后处理技术参数表 ;②运用影像工作站窗宽 (s shift)、窗位 (c shift)实施对影像密度和对比度的调节。③运用谐调处理和空间频率处理技术实施影像细节的调节。结果 易于给定曝光条件 ,曝光剂量减少了18% ,10 0 %地保证了胸片的质量 ,废片率为零。结论 掌握好床边X线摄影和CR系统各项技术 ,有助于提高图像质量和胸部病变的检出率  相似文献   
105.
An investigation has been carried out on the velocity resolution, spatial resolution and accuracy of Doppler images as part of a study into the Doppler display of cardiac tissue motion. Test-phantoms were designed to perform this work and images were captured on a computer. The characteristics of the phantom images and of the image capture process were studied. The smallest spatial detail that was observed in the Doppler image was 3 mm by 3 mm. Doppler receive gain and Doppler ensemble size both affected velocity resolution. Different target materials gave different measures for velocity resolution. This could be related to the different back-scatter intensities of the materials.  相似文献   
106.

Introduction

The optimal treatment of high energy tibial fractures remains controversial and a challenging orthopaedic problem. The role of external fixators for all these tibial fractures has been shown to be crucial.

Methods

A five-year consecutive series was reviewed retrospectively, identifying two treatment groups: Ilizarov and Taylor Spatial Frame (TSF; Smith & Nephew, Memphis, TN, US). Fracture healing time was the primary outcome measure.

Results

A total of 112 patients (85 Ilizarov, 37 TSF) were identified for the review with a mean age of 45 years. This was higher in women (57 years) than in men (41 years). There was no significant difference between frame types (p=0.83). The median healing time was 163 days in both groups. There was no significant difference in healing time between smokers and non-smokers (180 vs 165 days respectively, p=0.07), open or closed fractures (p=0.13) or age and healing time (Spearman''s r=0.12, p=0.18). There was no incidence of non-union or re-fracture following frame removal in either group.

Conclusions

Despite the assumption of the rigid construct of the TSF, the median time to union was similar to that of the Ilizarov frame and the TSF therefore can play a significant role in complex tibial fractures.  相似文献   
107.
Mitophagy, a selective autophagy of mitochondria, clears up damaged mitochondria to maintain cell homeostasis. We performed high-content analysis (HCA) to detect the increase of PINK1, an essential protein controlling mitophagy, in hepatic cells treated with several nanoparticles (NPs). PINK1 immunofluorescence-based HCA was more sensitive than assays and detections for cell viability and mitochondrial functions. Of which, superparamagnetic iron oxide (SPIO)-NPs or graphene oxide-quantum dots (GO-QDs) was selected as representatives for positive or negative inducer of mitophagy. SPIO-NPs, but not GO-QDs, activated PINK1-dependent mitophagy as demonstrated by recruitment of PARKIN to mitochondria and degradation of injured mitochondria. SPIO-NPs caused the loss of mitochondrial membrane potential, decrease in ATP, and increase in mitochondrial reactive oxide species and Ca2+. Blocking mitophagy with PARKIN siRNA aggravated the cytotoxicity of SPIO-NPs. Taken together, PINK1 immunofluorescence-based HCA is considered to be an early, sensitive, and reliable approach to evaluate the bioimpacts of NPs.  相似文献   
108.
Objectives:To assess the root proximity and the insertion angles of miniscrews after miniscrew placement at a variety of maxillary and mandibular buccal sites using cone-beam computed tomography (CBCT) and to determine the differences in root proximity between CBCT and panoramic radiography (PR).Materials and Methods:This retrospective study included 50 patients (mean age, 22.0 ± 4.5 years) who underwent postoperative CBCT and PR after miniscrew placements for intermaxillary fixation in orthognathic surgery. Twelve miniscrews were placed in the buccal bone of each patient: at sites between the central incisor and lateral incisor (SII), sites between the canine and first premolar (SCP), and sites between the second premolar and first molar (SPM) on the right and left sides of the mandible and maxilla. The insertion angles were measured on CBCT, and the root proximity was assessed on CBCT and PR.Results:The mean vertical placement angles ranged from 84.27° to 95.12°, and the mean horizontal placement angles ranged from 90.93° to 101.1°. The rates of no contact between the root and the miniscrew were 68.0% in the SII, 50.5% in the SCP, and 57.8% in the SPM, which were significantly different (P = .000). The total concordance rate between PR and CBCT was 41.3%.Conclusions:Clinicians should use extreme caution during placement of miniscrews in the SCP. There are limitations on the use of PR for evaluating the root proximity of miniscrews.  相似文献   
109.

OBJECTIVE

To analyze the methodology used for assessing the spatial distribution of specialized cardiac care units.

METHODS

A modeling and simulation method was adopted for the practical application of cardiac care service in the state of Santa Catarina, Southern Brazil, using the p-median model. As the state is divided into 21 health care regions, a methodology which suggests an arrangement of eight intermediate cardiac care units was analyzed, comparing the results obtained using data from 1996 and 2012.

RESULTS

Results obtained using data from 2012 indicated significant changes in the state, particularly in relation to the increased population density in the coastal regions. The current study provided a satisfactory response, indicated by the homogeneity of the results regarding the location of the intermediate cardiac care units and their respective regional administrations, thereby decreasing the average distance traveled by users to health care units, located in higher population density areas. The validity of the model was corroborated through the analysis of the allocation of the median vertices proposed in 1996 and 2012.

CONCLUSIONS

The current spatial distribution of specialized cardiac care units is more homogeneous and reflects the demographic changes that have occurred in the state over the last 17 years. The comparison between the two simulations and the current configuration showed the validity of the proposed model as an aid in decision making for system expansion.  相似文献   
110.

Objective

A number of studies provide supporting evidence for changes in synchronization during anesthetic-induced unconsciousness. This study investigates how anesthetic administration affects the widespread patterns of phase synchrony.

Methods

The recently introduced method of Spatial Analytic Phase Difference (SAPD) was used to measure changes in synchrony in the electroencephalogram (EEG) activity of 29 patients undergoing routine surgery. Analysis was performed over 9 frequency bands: (i) δ (1.5–3.5 Hz); (ii) θ (3.5–7.5 Hz); (iii) α1 (8–10 Hz); (iv) α2 (10.5–12 Hz); (v) β1 (12.5–18 Hz); (vi) β2 (18.5–21 Hz); (vii) β3 (21.5–30 Hz); (viii) γ1 (30.5–40 Hz); and (ix) γ2 (60–80 Hz).

Results

Anesthesia was characterized by (a) large and localized synchrony increases in mid-frequency bands (8–12 Hz), (b) smaller and widespread synchrony increases in higher frequency bands (30.5–40 Hz, 60–80 Hz), and (c) both increase and decrease of synchrony in low frequency bands (1.5–7.5 Hz).

Conclusions

This study supports anesthetic-induced changes in synchrony, with the inducement of persistent and reversible widespread γ synchrony being most prominent.

Significance

Our findings have implications in the study of consciousness, support existing literature in the field and contribute towards the theoretical understanding of the mechanisms behind loss of consciousness. Future investigations could result in a synchrony-based measure for monitoring the level of hypnosis of patients during surgery.  相似文献   
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