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61.
利用C8051 F340单片机以及无线控制技术实现对高频X射线机主控平台以及无线控制系统的设计与开发,为临床医生提供良好的人机交互方式,操作界面简单,能在多环境、多疾病、多操作的情况下可以进行远距离曝光操作。  相似文献   
62.
ObjectivesThis study sought to determine the feasibility, safety, and exploratory efficacy of the Embrella Embolic Deflector (EED) system (Edwards Lifesciences, Irvine, California) in patients undergoing transcatheter aortic valve replacement (TAVR).BackgroundFew data exist on the value of using embolic protection devices during TAVR.MethodsThis pilot study included 52 patients who underwent transfemoral TAVR. The EED system was used in 41 patients, whereas 11 patients underwent TAVR without embolic protection (control group). Cerebral diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at baseline and within 7 days and 30 days after TAVR.ResultsThe EED system was successfully deployed at the level of the aortic arch in all patients with no complications. The deployment of the EED system was associated with high-intensity transient signals (HITS) as evaluated by transcranial Doppler (median: 48 [interquartile range: 17 to 198] HITS), and a higher total number of HITS was observed in the EED group (p < 0.001 vs. control group). DW-MRI performed within 7 days after TAVR showed the presence of new ischemic lesions in all patients in both groups, with a median number of 7 (interquartile range: 3 to 13) lesions per patient. The use of the EED system was associated with a lower lesion volume compared with the control group (p = 0.003). All new cerebral lesions had disappeared on the DW-MRI performed at 30 days after TAVR. Two strokes unrelated to the EED system occurred 2 and 29 days after TAVR.ConclusionsThis study showed the feasibility and safety of using the EED system in TAVR procedures. The EED system did not prevent the occurrence of cerebral microemboli during TAVR or new transient ischemic lesions as evaluated by DW-MRI, but it was associated with a reduction in lesion volume. Further studies are warranted to determine the efficacy of using the EED system during TAVR procedures.  相似文献   
63.
医师资格考试是大多数国家普遍采用的医师资格认证形式。医学人文的考核在医师资格考试中占有重要地位。以临床类别考试为例,通过文献分析、比较研究的方法,比较分析中美两国执业医师资格考试和医师资格分阶段考试实证研究考试中的医学人文考核,包括考试内容和形式、考试分值及比例。发现两国医学人文考核内容和比例基本相当,但我国现行考试医学人文考核站数较少,考试形式和呈现方式有待进一步改善,下一步应继续探索标准化病人应用于我国医师资格考试的可行性,充分发挥医师资格考试对医学教育的导向作用。  相似文献   
64.
目的:探讨不同密度胸腺囊肿CT表现差异及其病理基础。方法:回顾分析手术病理证实的45例实性密度胸腺囊肿和23例液性密度胸腺囊肿CT表现及其病理改变。结果:胸腺囊肿密度与囊肿大小有相关性(P<0.01)。实性密度囊肿形态多较规则,液性密度囊肿以不规则、沿大血管间隙塑形多见,组间分布差异有统计学意义(P<0.01)。泪滴状及三角状在2组均可见,组间分布差异无统计学意义(P>0.05)。实性密度囊肿多不膨隆于胸腺轮廓,与液性密度相比差异有统计学意义(P<0.01)。实性密度胸腺囊肿病理表现为有分泌功能的假复层纤毛柱状上皮或纤毛柱状上皮覆盖,囊壁上皮细胞排列较密实,囊液多浑浊;液性密度胸腺囊肿被覆表面为无分泌功能扁平或柱状上皮为主,排列稀疏甚至缺失,基层薄弱,囊液往往较清亮。囊肿密度与被覆上皮类型有相关性(P<0.05)。结论:胸腺实性密度囊肿与液性密度囊肿影像学表现有差异,病理基础对理解不同表现胸腺囊肿有帮助。  相似文献   
65.
Although less extensively studied compared to pulmonary obstructive diseases, restrictive lung disease (RLD) is highly prevalent and frequently disabling in the adult and, more, the elderly population. The underlying conditions may be either primarily pulmonary diseases, such as idiopathic pulmonary fibrosis, or non respiratory conditions secondarily affecting the lung, e. g. congestive heart failure, or else conditions affecting the lung expansion, e. g. obesity or rib cage deformity. The diagnosis is frequently based on the measurement of surrogate indexes such as the forced vital capacity (FVC) used as a proxy for total lung capacity (TLC). As a consequence, diagnosis of RLD is often characterized by poor specificity. In the elderly, worsening in the quality of life and poor prognosis are variably, but significantly, associated to RLD, being the underlying condition an important source of variability. Several causes of RLD are preventable and treatable conditions. A prompt identification of these conditions may allow to slow the decline of respiratory reserve and, thus, to preserve both personal independence and resistance to acute respiratory infections. This review gives an update on the latest evidence available on the prevalence and the prognosis of RLD in the elderly. Studies were identified through systematic searches of the electronic database MEDLINE. Reference list of eligible papers were also manually searched.  相似文献   
66.
BackgroundThe authors conducted an analysis of data from the National Health and Nutrition Examination Survey (NHANES) to understand the association between diabetes and tooth loss in the United States.MethodsThe authors analyzed the oral examination and self-reported diabetes data obtained from the NHANES 2003–2004 cycle and included 2,508 participants representing a civilian, noninstitutionalized U.S. population 50 years and older. The authors calculated the prevalence of edentulism and the number of missing teeth among dentate people, and they used multiple regression analyses to assess the association between diabetes and tooth loss.ResultsThe prevalence of edentulism was 28 percent and 14 percent among people with and without diabetes, respectively. The multiple logistic regression analysis revealed that people with diabetes were more likely to be edentulous than were those without diabetes (adjusted odds ratio = 2.25; 95 percent confidence interval, 1.19–4.21). Among dentate adults, those with diabetes had a higher number of missing teeth than did adults without diabetes (mean [standard error {SE}] = 9.8 [0.67]), mean [SE] = 6.7 [0.29]); P < .01).ConclusionsThese study results revealed that adults with diabetes are at higher risk of experiencing tooth loss and edentulism than are adults without diabetes. One of every five cases of edentulism in the United States is linked to diabetes.Practical ImplicationsAlthough the association between diabetes and periodontal disease is well established, health care professionals also need to recognize the risk of tooth loss and its effect on quality of life among people with diabetes.  相似文献   
67.
Context/Objective: The examination for Spinal Cord Injury (SCI) Medicine subspecialty certification has been administered since 1998, but published information about exam performance or administration is limited.

Design: Retrospective review

Setting/Participants: We examined de-identified information from the American Board of Physical Medicine and Rehabilitation (ABPMR) database for characteristics and performance of candidates (n?=?566) who completed the SCI Medicine Examination over a 10-year period (2005–2014), during which the exam outline and passing standard remained consistent.

Interventions: Not applicable

Outcome Measures: We analysed candidate performance by candidate track, primary specialty, number of attempts, and domains being tested. We also examined candidate perception of the SCI Medicine Exam by analysing responses to a survey taken after exam completion.

Results: Thirty-six percent of candidates who completed the exam during the study period took it for initial certification (23% in the fellowship track and 13% in the practice track offered during the initial “grandfathering” period) and 64% took it for maintenance of certification (MOC) in SCI Medicine. Factors associated with better exam performance included primary specialty certification in Physical Medicine and Rehabilitation (PM&R) and first attempt at passing the exam. For PM&R candidates, ABPMR Part I Examination scores and SCI Medicine Examination scores were strongly correlated. Candidate feedback about the exam was largely positive with 97% agreeing or strongly agreeing that it was relevant to the field and 90% that it was a good test of their knowledge.

Conclusion: This study can inform prospective candidates for the SCI Medicine Examination as well as those guiding them. It may also provide useful information for future exam development.  相似文献   
68.
The aim of this study was to investigate the prevalence of mental disorder and associated factors during an economic recession. Random samples of Finnish general population were collected in 3 consecutive years, 1993-95. The prevalence of mental disorders was assessed by means of the 12-item General Health Questionnaire (GHQ). The prevalence of mental disorders varied among Finnish men from 15.6% to 19.2% and among women from 21 to 24.5%. Mental disorder was more common among women than among men in every study year. Mental disorder was more common among the unemployed than among other respondents both in women and men in every year. Subjective poor health, suicidal thoughts and poor economic situation were constantly associated with mental disorder in both sexes every year. Using logistic regression analyses, problems with a partner, uncertain future orientation and use of psychoactive drugs, in particular, were found to be fairly permanent independent risk factors in relation to mental disorder. As studied by gender no major changes occurred in the mental health status of Finns during economic recession, although in many specific groups mental disorder was markedly more common than in the general population.  相似文献   
69.
目的比较蒙特利尔认知评估量表(MOCA)和简易精神状态量表(MMSE)对脑白质疏松(LA)患者认知功能障碍的筛查能力,并了解lA患者认知功能受损的特点。方法应用MoCA量表及MMSE量表对56倒LA患者及50例对照的认知功能进行测评,比较两组的测试结果,并比较两量表对LA组中VCI患者的诊断能力。结果LA组的MoCA总评分(20.34±3.00)分明显低于对照组(22.20±2.26)分,差异有统计学意义(t-4.02,P〈O.01);其中,LA组的命名、语言、抽象、定向力评分均小于对照组,差异有统计学意义(t分别为3.92,3.43,4.02,5.35;P〈0.01)。LA组的MMSE总评分(27.54±1.36)分低于对照组(28.06±1.92)分,差异有统计学意义(t-2.36,P〈0.05),其中LA组的定向力及延迟回忆评分低于对照组,差异有统计学意义(t分别为2.68,2.60;P〈0.05)。在LA组中,MoCA诊断VCI的敏感度为93.9%、特异度63.6%、假阳性率36.4%、假阴性率9.1%、阳性预测值91.3%、阴性预测值70.0%、诊断符合率84.2%、约登指数0.569;MMSE诊断VCI的上述指标分别为26.7%,90.9%,6.7%,73.3%,92.3%,23.3%,43.4%,0.176。结论LA患者的认知功能受损表现在命名、语言、抽象、定向力及延迟回忆等方面。MoCA量表在筛查LA患者认知功能方面比MMSE量表更敏感。  相似文献   
70.
目的分析儿童盆腔卵黄囊瘤的临床、病理及64层螺旋CT(MSCT)特点,以提高对本病的诊断水平。方法回顾性分析34例经手术病理检查证实的盆腔卵黄囊瘤儿童的临床、病理、MSCT及多平面重建资料。术前均行盆腔MSCT平扫及增强扫描。结果本组34例中,女性21例,男性13例;患儿年龄3个月至7岁3个月,平均(18±15)个月龄。临床表现主要为腹部或骶尾部肿块以及腹痛。33例甲胎蛋白(AFP)明显升高,1例(占2.9%)AFP值为2.2 ng/mL。34例患儿中,18例来源于盆腔腹膜腔内,16例位于腹膜腔外向骶尾部生长,其中9例主体部分位于盆腔,7例主体部分位于骶尾部。MSCT均表现为卵圆形或不规则形囊实性肿块,增强后肿瘤的实性部分明显强化,肿块最大径为2.8~10.7 cm。AFP值与肿块大小及部位无显著相关性。结论盆腔卵黄囊瘤的临床及MSCT表现有一定特征,CT能较准确描述肿瘤内部结构与血供,结合血清AFP检查,有利于盆腔卵黄囊瘤的正确诊断、制订术前手术方案及判断术后复发情况。  相似文献   
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