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21.
目的 评价美国国家电器制造协会(National Electrical Manufactures Association, NEMA)最新标准(NU 2-2018)在正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography, PET/CT)设备性能检测中的作用。 方法 依据最新的NEMA NU 2-2018标准,检测西门子Biograph Vision PET/CT的空间分辨率、灵敏度、散射分数、计数丢失、随机符合、飞行时间分辨率、计数丢失率和随机符合校正精度、图像质量、衰减和散射校正精度及PET与CT配准精度指标。 结果 距视野中心1 cm处横向和轴向空间分辨率分别为3.75 mm和3.76 mm;在视野中心和轴向10 cm处的灵敏度分别为16.83 kcps/MBq和16.67 kcps/MBq;放射性浓度为27.37 kBq/mL时,最大等效噪声计数率为258.26 kcps,散射分数为38.58%;系统时间分辨率为209.82 ps;图像质量模型的对比度恢复系数范围为88.9%~96.2%,背景变异系数范围为2.05%~6.80%,平均肺插件残余误差为2.43%;计数丢失和随机符合校正最大误差为3.9%;距离床板末端 5 cm 和 100 cm处,在距视野中心Y轴1 cm处,PET和CT的配准精度分别为0.46 mm和1.07 mm,在距视野中心X轴20 cm处,PET和CT的配准精度分别为1.06 mm和1.45 mm,在距视野中心Y轴20 cm处PET和CT的配准精度分别为0.85 mm和1.15 mm。 结论 NEMA NU 2-2018标准检测条件更加接近临床,能更好地反映PET/CT设备的系统性能。  相似文献   
22.
This meta-analysis was designed to assess the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for patients with low back pain (LBP). Pubmed, Embase, Cochrane's library, PEDro (Physiotherapy Evidence Database), China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched until December 2019 to identify studies assessing the effectiveness and safety of EPSW for LBP. The prime outcome is pain intensity measured by Visual Analog Scale (VAS) or numeric rating scale (NRS). Other outcomes included functional status, quality of life, psychological outcomes measured by Oswestry Disability Index (ODI), as well as the adverse events. Mean differences (MD) were calculated for continuous outcomes, while odd ratios (OR) were calculated for binary outcomes. Revman 5.3 software was used for statistical analysis. Five randomized controlled trials (RCTs) were finally included in this meta-analysis. The pooled mean difference in post-treatment pain scores was −2.37 (P <0.0001), indicating that post-treatment pain scores was significantly higher by 2.37 in control group than in ESWT group. At a mean follow-up time of 4–6 weeks, the pooled mean difference in ODI scores was −14.10 (P <0.00001), indicating that the pooled mean difference of post-treatment ODI scores was 14.10 higher in control group than in ESWT group. The use of ESWT is effective in alleviating pain and improving the general functional state for patients with LBP. However, more evidence was needed to verify its safety.  相似文献   
23.
《Value in health》2022,25(3):340-349
ObjectivesThis study aimed to systematically review recent health economic evaluations (HEEs) of artificial intelligence (AI) applications in healthcare. The aim was to discuss pertinent methods, reporting quality and challenges for future implementation of AI in healthcare, and additionally advise future HEEs.MethodsA systematic literature review was conducted in 2 databases (PubMed and Scopus) for articles published in the last 5 years. Two reviewers performed independent screening, full-text inclusion, data extraction, and appraisal. The Consolidated Health Economic Evaluation Reporting Standards and Philips checklist were used for the quality assessment of included studies.ResultsA total of 884 unique studies were identified; 20 were included for full-text review, covering a wide range of medical specialties and care pathway phases. The most commonly evaluated type of AI was automated medical image analysis models (n = 9, 45%). The prevailing health economic analysis was cost minimization (n = 8, 40%) with the costs saved per case as preferred outcome measure. A total of 9 studies (45%) reported model-based HEEs, 4 of which applied a time horizon >1 year. The evidence supporting the chosen analytical methods, assessment of uncertainty, and model structures was underreported. The reporting quality of the articles was moderate as on average studies reported on 66% of Consolidated Health Economic Evaluation Reporting Standards items.ConclusionsHEEs of AI in healthcare are limited and often focus on costs rather than health impact. Surprisingly, model-based long-term evaluations are just as uncommon as model-based short-term evaluations. Consequently, insight into the actual benefits offered by AI is lagging behind current technological developments.  相似文献   
24.
GIS is increasingly popular in the study of complex social issues, such as homelessness. This study aims to assess how GIS has been leveraged and applied to homelessness research and service delivery. Systematic searching of sixteen databases was completed between January and March of 2021 using the terms “homeless” and “Geospatial Information Systems (GIS).” A final sample of 19 sources were identified from a total of 1719 identified sources. Through quantitative and qualitative methods, the included sources examined 1) static location characteristics associated with homelessness, and 2) mobility of homeless persons.  相似文献   
25.
目的了解北京市房山区梅毒规划(2010—2020年)实施期间梅毒防治效果和各考核指标达标情况,为下一步制定有效的梅毒防治策略提供科学依据。方法根据《中国预防与控制梅毒规划(2010—2020年)》(以下简称《梅控规划》)终期评估的要求,通过专网、现场调查、APP答题等方式对涉及的16个指标进行收集,并将16个指标划分为梅毒防治保障措施的落实、防治工作开展和防治效果3个层面进行评估,同时将评估结果与终期评估标准进行比较。采用SPSS 18.0软件进行描述性统计分析。结果2010—2020年北京市房山区共报告梅毒病例3260例,年均报告发病率27.99/10万,年均增长0.08%,男女比例基本持平,以25岁年龄组病例数最多,历年病例均以隐性梅毒为主。保障措施与能力建设方面均达标;防治工作方面:感染梅毒的孕产妇所生婴幼儿接受规范诊疗服务的比例为50.00%,梅毒患者接受规范化治疗的比例86.11%,两指标未达标,其余均达标;防治效果中一期和二期梅毒年报告发病率增长幅度为3.80%,未达标,先天梅毒年报告发病率为9.25/10万活产数达到了《梅控规划》的工作要求。结论2010—2020年北京市房山区梅毒防治工作取得了一定成效,但部分指标仍未达标,应继续加强梅毒防治工作,尤其是需提高规范化诊疗的比例同时控制新发梅毒发病率。  相似文献   
26.
脑转移瘤是成人最常见的颅内肿瘤,发病率呈上升趋势。影像组学可对医学影像进行定量分析处理来指导临床实践。近年来,基于CT、MRI的影像组学逐渐应用于脑转移瘤的精准诊疗,如肿瘤精准检测和分割、与其他脑肿瘤的鉴别诊断、原发肿瘤的判别、疗效评价及预后预测等。本文就脑转移瘤影像组学研究现状予以综述。  相似文献   
27.
ObjectiveMultiple treatment options for acetabular fractures in geriatric patients exist. However, no large-scale studies have reported the outcomes of acute total hip arthroplasty (THA) in this patient population. We systematically evaluated all available evidence to characterize clinical outcomes, complications, and revisions of acute THA for acetabular fractures in geriatric patients.MethodsMeta-analysis of 21 studies of 430 acetabular fractures with mean follow-up of 44 months (range, 17−97 months). Two independent researchers searched and evaluated the databases of Ovid, Embase, and United States National Library of Medicine using a Boolean search string up to December 2019. Population demographics and complications, including presence of heterotopic ossification (HO), dislocation, infection, revision rate, neurological deficits, and venous thromboembolic event (VTE), were recorded and analyzed.ResultsWeighted mean Harris Hip Score was 83.3 points, and 20% of the patients had reported complications. The most common complication was HO, with a rate of 19.5%. Brooker grade III and IV HO rates were lower at 6.8%. Hip dislocation occurred at a rate of 6.1%, 4.1% of patients developed VTE, deep infection occurred in 3.8%, and neurological complications occurred in 1.9%. Although the revision rate was described in most studies, we were unable to perform a survival analysis because the time to each revision was described in only a few studies. The revision rate was 4.3%.ConclusionsAcute THA is a viable option for treatment of acetabular fracture and can result in acceptable clinical outcomes and survivorship rates in older patients but with an associated complication rate of approximately 20%. Considering the limited treatment options, THA might be a viable alternative for appropriately selected patients.  相似文献   
28.
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
29.
Depression is a heterogeneous disorder with a wide range of presentations. Most patients with depression are seen in primary care, where it is often unrecognized; thus, screening for depression is important. Medical conditions can mimic depression and vice versa. For mild cases of depression, symptom monitoring and nonpharmacologic strategies are generally recommended initially, whereas psychotherapy and antidepressant drugs are first-line treatment for moderate to severe cases. Patients with depression often experience relapse, recurrence, or both, and multiple options are available. Primary care providers are central to screening, diagnosing, and subsequently treating or referring these patients.  相似文献   
30.
ObjectivesSingle-gene testing is associated with psycho-social challenges for cancer patients. Genomic testing may amplify these. The aim of this study was to understand patients’ motivations and barriers to pursue cancer genomic testing, to enable healthcare providers to support their patients throughout the testing process and interpretation of test results.MethodsFive databases were searched for original peer reviewed research articles published between January 2001 and September 2018 addressing motivation for genomic cancer testing. QualSyst was used to assess quality.Results182 studies were identified and 17 were included for review. Studies were heterogenous. Both somatic and germline testing were included, and 14 studies used hypothetical scenarios. 3249 participants were analyzed, aged 18 to 94. Most were female and white. The most common diagnoses were breast, ovarian, lung and colorectal cancer. Interest in testing was high. Motivations included ability to predict cancer risk, inform disease management, benefit families, and understand cancer. Barriers included concerns about cost, privacy/confidentiality, clinical utility, and psychological harm.ConclusionsDespite concerns, consumers are interested in cancer genomic testing if it can provide actionable results for themselves and their families.Practice ImplicationsProviders must manage understanding and expectations of testing and translate genetic information into health-promoting behaviours.  相似文献   
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