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991.
目的 对江西省医疗机构医用X射线诊断设备进行应用频度抽样调查,掌握江西省医用X射线诊断应用频度水平和受检者的分布特点,估算全省普通X射线诊断、计算机X射线断层摄影装置(CT)、介入放射学的应用频度水平。方法 采用分层典型抽样方法,在全省范围内抽取三级、二级、一级和其他各级样本医院,以发放调查问卷的形式对样本医院进行应用频度的调查与分析。结果 医用X射线诊断受检者男性多于女性;年龄分布中"0~"组比例最低,"40~"组占比例最高;估算出江西省2016年度X射线诊断频度约为543.07次/千人口,CT诊断频度约为244.79次/千人口,介入放射学频度约为6.28次/千人口。结论 江西省医用X射线诊断应用频度迅猛发展,给放射卫生工作提出了巨大的挑战,因此应加强医用X射线诊断医疗照射的监督管理并合理配置使用各类医疗资源。  相似文献   
992.
心率变异和RT变异频域分析的方法学研究   总被引:5,自引:3,他引:5  
心率变异作为检测自主神经系统功能平衡状态的无创性指标,日益受到重视,已成为心电信号处理中的研究热点之一。QT是心室肌复极化时间,从另一方面来反映自主神经系统的平衡状态。QT变异分析在临床应用上与心率变异分析是否有互补作用,目前这方面研究工作开展得不多。由于QT间期检测困难,一般以RT间期代替QT间期。建立了心率变异和QT变异测定方法。在采集24h心电信号后,首先要完成标志点的检测。较好地实现了心电R波标志点的检测和异位心跳的剔除,并采用以相关系数为条件的模板匹配方法检测出T波标志点。频域分析方法分别通过快速傅里叶变换法(FFT)和自回归谱估计法(AR)实现了24h三维频谱显示图以及24hHF/LF和高频能量变化趋势图。以不同的频率控制受试者的呼吸,采集其心电数据,从RR间期和RT间期谱分析的结果可以看到,高频峰受到呼吸频率的调制,高频峰可能与迷走神经活动有关。这一过程也检验了心电信号采集、检测和谱分析方法的可靠性。建立的方法为今后进一步深入研究打下了基础。随着心率变异和QT变异的检测和分析技术的日趋成熟,一定会在一些疾病的早期诊断、监护及预后评估等方面发挥更大的作用  相似文献   
993.
Airway management during carinal resection should provide adequate ventilation and oxygenation as well as a good surgical field, but without complications such as barotraumas or aspiration. One method of airway management is high frequency jet ventilation (HFJV) of one lung or both lungs. We describe a patient undergoing carinal resection, who was managed with HFJV of one lung, using a de-ballooned bronchial blocker of a Univent tube without cardiopulmonary compromise. HFJV of one lung using a bronchial blocker of a Univent tube is a simple and safe method which does not need additional catheters to perform HFJV and enables the position of the stiffer bronchial blocker more stable in airway when employed during carinal resection.  相似文献   
994.
The study focuses on 12 breasts of six breast cancer patients sequential µm-wavelength imaging, taken by two different 3–5 μm wavelength area indium antimony (InSb) photovoltaic cameras. The aim of the study was to compare the functionality of area and pixel-based frequency analyses. Comparisons between these frequency analysis methods were made according to their relevancy to mammographic findings. Another objective of the study was to find reliable imaging conditions by specifying the border conditions for the patient stabilizing imaging bed and managing the imaging situation. According to the results, the match of pixel based frequency analysis to the mammography findings is better than using area frequency analysis. The results also indicate that when the optical axis of the camera in relation to the surface of the breast to be imaged grows to more than 40°, the emissivity changes dramatically and at that point reliable results will not be obtained. Consequently the analysis of the imagined breast requires more images to be fused into one analysis image to cover the whole breast.  相似文献   
995.
Background and study aimsBarrett's Esophagus (BE) is a well-recognized pre-malignant condition. Previous data indicate histologically confirmed BE frequency varies by ethnicity in the United States. However, clinical factor assessment to explain this has only occurred in a veteran population to date. The study aim was to determine which clinical factors may be associated with the ethnic variation seen in histologically confirmed BE among a general population.Patients and methodsThe University of Florida-Jacksonville endoscopy database was searched for all cases of endoscopic BE from September 2002 to October 2012. Histologic BE was diagnosed only if salmon colored, columnar-appearing esophageal mucosa was seen at endoscopy and biopsy revealed intestinal metaplasia with Alcian blue-stained goblet cells. Data collected included: age/BMI at diagnosis, ethnicity, sex, GERD history, atypical manifestations, endoscopic BE length, presence of esophageal stricture/ulcer/hiatal hernia, presence/absence of dysplasia and medication use (aspirin/NSAIDs/statin/PPI).ResultsSalmon colored esophageal mucosa was observed in 1105 of 15,564 patients (7.1%) with BE histologically confirmed in 249 of 1105 patients (23%). Ethnic distribution of histologic BE patients: 83% non-Hispanic white (nHw), 13% African American (AA) and 4% other. No difference was seen between groups with regard to BMI, GERD symptom/complications, BE length, and cigarette, alcohol or medication use.ConclusionBE occurs primarily in nHw in north Florida. This occurs despite similarities in GERD history, cigarette/alcohol use, medications prescribed and BMI. Molecular level investigation is necessary to explain this observed disparity between nHw and AA.  相似文献   
996.
997.
为掌握我国X射线诊断的基本情况及其应用频度与分布,为X射线诊断应用的监督管理提供基础数据,本项目组设计相关调查表并通过预调查进行优化,采用分层配额抽样方法,在全国25省市选择了共557家医疗机构进行基本情况调查,并按照类型、性别、年龄组等分别统计人次数,进行多重线性回归分析估算我国2016年X射线诊断应用频度。估算结果表明,2016年我国10个省份的X射线诊断频度为379~1 228人次/千人口。全国X射线诊断应用发展迅速,与"九五"期间相比明显增加,应进一步加强X射线诊断应用管理。  相似文献   
998.
Documenting assistive technology outcomes has grown in importance, but outcome measurement remains problematic. A new approach uses natural science measures and a model (selectionism) from the field of Behavior Analysis. Selectionism defines behaviors by their effects (functional performance) and the environment (including technology) within which they occur, and explicitly treats variation in patterns of behavior over time for individuals (intervention effects). Its basic metric is frequency of behaviors (count per unit time) which is similar to robust engineering measures like centimeters, grams, and seconds. This approach eliminates many of the problems inherent to more traditional psychometrics. Selectionism based on frequencies also provides an empirical structure or taxonomy to organize efforts and outcomes, unified by the notion of fluency. Composite behaviors are combinations of smaller component behaviors that are required for performance of the composite. A frequency above which a component behavior is readily retained, generalized, and recruited into the more complex composite behavior is called fluency; thus individuals fluent on the critical components easily and efficiently demonstrate the composite. This model suggests that when assistive technology interventions raise component behavior frequencies to fluent levels, they will be integrated usefully into an individual's life. This selectionistic approach has been used successfully in the field of education. It has the added benefit of not only empirically defining measurable outcomes, but also of providing useful ongoing measurement of change during treatment. This paper briefly describes this “Precision Measurement” strategy and its data-driven feedback process and makes suggestions for further research and development efforts. The method provides a basis for better documentation, control, and outcomes of assistive technology and related interventions.  相似文献   
999.
Gastroesophageal reflux disease (GERD) is common in patients with many chronic diseases, but has not been well recognized in rheumatoid arthritis (RA). We investigated the prevalence of GERD symptoms in 278 outpatients with RA and their association with such clinical factors as age, sex, height, weight, body mass index, medications drugs, and functional status evaluated by the Modified Health Assessment Questionnaire (MHAQ). GERD symptoms were evaluated by Frequency Scale for the Symptoms of GERD (FSSG). The mean FSSG score for all patients was 5.6, and 82 patients were considered to have GERD symptoms (FSSG score ≥8), thus the overall prevalence of GERD symptoms was 29.5%. MHAQ score and height were significantly higher and lower, respectively, and prednisolone usage was significantly more in the patients with GERD symptoms than those without. These three clinical factors were also significantly associated with GERD symptoms by univariate logistic regression. Multivariate logistic regression analysis demonstrated that MHAQ was the only clinical factor related to GERD symptoms. In conclusion, the prevalence of GERD symptoms in RA patients was high and strongly associated with decreased functional status, suggesting that physicians should pay attention to GERD symptoms in RA management, especially for patients with low functional status.  相似文献   
1000.
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