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111.
An increasing demand for polycistronic vectors that express multiple genes simultaneously has arisen in recent years to obtain an efficient gene therapy. Armed with the knowledge that the expression of transgene in mammalian cells often requires tight control, we constructed in this study a tetracycline-regulated double-gene adeno-associated virus (AAV) vector carrying green and red fluorescent protein genes and expressed it in PC12 cells. When detected by fluorescence microscope and fluorescence-activated cell sorting, gene expression was induced by 44-66-fold and could be reversibly controlled by doxycycline. This double-gene AAV vector may be useful for regulated expression of two genes or a marker to monitor transgene expression. 相似文献
112.
目的 :研究急性心肌缺血和梗死的多层螺旋CT(MSCT)心肌灌注特点 ,探索MSCT冠状动脉造影对冠状动脉阻断的显示情况。方法 :犬左冠状动脉前降支结扎前、后不同时期分别进行MSCT心肌灌注扫描 ,分析其特点 ,并与病理检查相对照 ;同时做MSCT冠状动脉造影观察冠状动脉阻断的情况。结果 :犬心肌正常灌注量为 ( 69.3±1 3 .9)ml·1 0 0g- 1·min- 1、达峰值时间 ( 1 2 .8± 2 .1 )sec。左冠状动脉前降支结扎 3 0min后MSCT心肌灌注表现为灌注量减低 ,时间密度曲线低平 ,延迟 1 0min扫描局部心肌密度无显著改变。结扎 4h后 ,局部心肌呈明显延迟增强。MSCT冠状动脉造影显示冠状动脉前降支中断。结论 :MSCT心肌灌注结合冠状动脉造影可以判断心肌缺血和梗死 ,同时显示冠状动脉的阻塞状况 相似文献
113.
Neil E Alexis Willie June Brickey John C Lay Ying Wang Robert A S Roubey Jenny P Y Ting David B Peden 《Annals of allergy, asthma & immunology》2008,100(3):206-215
BACKGROUND: Environmental exposure to endotoxin is a known cause of exacerbation of asthma. Inhaled endotoxin protocols have been used to evaluate airway cell surface phenotypes associated with antigen presentation and innate immunity in healthy volunteers, but not in allergic volunteers. OBJECTIVES: To establish the safety of challenge with low-dose endotoxin (10,000 endotoxin units) (lipopolysaccharide [LPS]) inhalation in allergic individuals, to measure airway cell surface phenotypes associated with antigen presentation and innate immunity in induced sputum (IS) after LPS challenge, and to conduct gene expression profiling in IS cells to determine which host genetic networks are modified by LPS inhalation. METHODS: Induced sputum was obtained before and 6 hours after LPS inhalation in 10 allergic volunteers (8 with asthma and 2 with rhinitis). Flow cytometry was used to examine cell surface phenotypes on IS cells. Genomic expression was analyzed on a subset of IS samples (n = 10) using microarray and ingenuity pathway analysis. RESULTS: A total of 10,000 endotoxin units of LPS induced significant up-regulation of membrane CD14, CD11b, CD16, HLA-DR, CD86, and Fcepsilon receptor 1 on sputum phagocytes and increased expression of genes that influence antigen-presenting surface molecules (HLA-DR, chemokine ligand 2 or monocyte chemoattractant protein 1, v-rel reticuloendotheliosis viral oncogene homolog, prostaglandin-endoperoxide synthase 2 or cyclooxygenase 2, and transforming growth factor beta), immune activation (CD14, interleukin 1beta, and regulated upon activation, normal T cell expressed and secreted), and inflammation (intracellular adhesion molecule 1 and inhibitory kappaBalpha). Gene profiles for nuclear factor kappaB, interleukin 1, and tumor necrosis factor pathways were also significantly affected. CONCLUSIONS: Low-dose inhaled endotoxin challenge is safe in allergic individuals with mild to moderate disease. It enhances airway cell surface phenotypes and expression of genes associated with antigen presentation, innate immunity, and inflammation. Microarray with ingenuity pathway analysis can be successfully applied to sputum cells to characterize genetic responses to inhaled exacerbants. 相似文献
114.
目的 了解四川省成人常住居民糖尿病患病情况及其影响因素,为有效预防糖尿病,降低发病风险提供科学的依据。方法 2018年采用多阶段分层整群随机抽样的方法,抽取四川省18岁及以上常住居民进行身体测量、问卷调查、实验室检测。采用SAS 9.4分析四川省成人糖尿病流行情况和患病影响因素。结果 2018年四川省成人糖尿病患病率12.94%,其中男性患病率为13.09%,女性患病率为12.79%,差异无统计学意义(χ2=3.964,P=0.460); 年龄增长(与18~44岁组相比,75岁及以上OR=6.070,95%CI:3.792~9.716)、职业(与农业生产人员相比,离退休人员OR=1.781,95%CI:1.277~2.484)、锻炼频率(与每周0次相比,每周1~3次OR=0.439,95%CI:0.281~0.686)、血脂异常(OR=2.069,95%CI:1.693~2.528)、中心性肥胖(OR=1.938,95%CI:1.619~2.320)、高血压(OR=2.031,95%CI:1.583~2.606)、糖尿病家族史(OR=2.825,95%CI:1.658~4.813)是糖尿病患病的影响因素。结论 四川省糖尿病患病率处于较高水平,每周锻炼1~3次是预防糖尿病的保护因素,年龄增加、离退休人员、血脂异常、中心性肥胖、高血压、糖尿病家族史是糖尿病患病的危险因素,应进一步开展针对性的预防干预措施。 相似文献
115.
目的 评估重庆市2011—2020年结核病防治经费投入产生的社会效益。方法 收集《传染病监测系统》中2011—2020年重庆市登记涂阳肺结核患者(初治涂阳和复治涂阳)治疗转归情况和肺结核患者劳动人口比例,历年各级政府结核病防治经费投入,历年全市人均国内生产总值(gross domestic product,GDP)等数据,采用常用卫生经济学方法评估10年间结核病防治经费投入的社会效果、社会效用和社会效益。结果 2011—2020年,全市共投入结核病防治经费约3.60亿元,成功治疗涂阳肺结核患者60 924例,避免45.69万名健康人受传染,挽救43.41万个伤残调整生命年(disability adjusted life year,DALY),为社会节约医疗费用3.26亿元,挽回社会经济损失约176.25亿。保持目前的设施设备和人员条件不变,每投入787.70元即可避免1名健康人被传染,每投入829.16元即可挽救1个DALY,每额外投入1元即可产生49.87元的经济效益。结论 10年间重庆市结核病防治经费投入产生了较大的卫生经济效益,建议各级政府继续加大结核病防治经费投入。 相似文献
116.
目的:探索有效的重点药品合理使用管控措施,为医疗机构重点监控药品的监管提供参考。方法:基于QRTCC模型,围绕目标、规则、培训、考核、文化5个要素,设置年度重点监控药品管控目标,设立处方点评专家组与处方点评工作小组,遴选医院重点监控药品目录,建立重点监控药品管理制度与重点监控药品医嘱点评制度,对重点监控药品采取动态监测、考核、熔断目录与培训等一定的干预措施。结果:采用此模式对重点监控药品合理使用进行了精细化管理,干预后医院重点监控药品收入、住院患者重点监控药品使用费用、重点监控药品使用强度、医师开具医嘱的不合理率均有所下降,改善效果明显(P<0.05),但中成药、特殊使用抗菌药物的医嘱合理率改善效果不佳,仍需后续进一步研究。结论:基于ORTCC模式的重点监控药品管控措施成效显著,重点监控药品的使用强度与费用均显著下降,医嘱合理率得到较大提升,在一定程度上提升了医院合理用药水平,保障患者用药安全并减轻了就医负担。 相似文献
117.
微流控肝、肾芯片是近年来进行新药研发、药效毒理研究和机制探索、疾病模型构建的优选模型载体。在美国食品药品监督管理局允许当动物疾病模型难以构建时,用体外模型数据代替动物模型数据进行新药申报的大背景下,微流控芯片因为具有高通量、能高度仿生生命体特征、可方便进行重复给药的正常或病理状态下的药物毒性评价且允许对培养物培养过程进行实时诱导、监测过程数据实时采集分析等优点而得到广泛的关注。在毒理学研究中,肝、肾芯片可以通过结合不同物种来源的2D单培养和共培养、3D培养、球状体/类器官细胞、精密切割肝、肾切片、永生化细胞系或夹心培养细胞系等培养物,构建适合不同物质药效毒理学检测的体外模型。该模型最大化模拟或保留肝脏和肾脏的脏器功能和体内微环境,包括特定的生理组织结构、多细胞相互作用/串扰、多器官相互协作/反馈等,以得到与体内实验数据相近或相同的结果,减少了不同种属之间的差异;同时大大减少实验动物的使用,降低了成本。微流控技术提供的微流体不仅能为内容物培养提供必要的剪切力微环境,还能解决目前由于肝、肾芯片培养过程中组织供氧不足、营养物质的缺失、代谢物堆积,导致的细胞凋亡甚至组织坏死纤维化,难以长期维持... 相似文献
118.
目的:探索脑卒中患者促进上肢运动功能恢复中头针与镜像疗法联合应用的临床价值。方法:选取株洲市中心医院2021年8月至2022年11月期间收治的60例脑卒中后上肢功能障碍患者,以随机分组的方式分为两组,每组30例。其中常规康复训练联合镜像治疗纳入对照组,在对照组基础上增加头针治疗纳入观察组。在治疗4周后,比较两组患者临床治疗有效性、Fugl–meyer运动功能评定量表(FMA)上肢部分评分以及Brunnstrom分期。结果:两组患者治疗后FMA评分均高于治疗前,且观察组患者治疗后FMA评分高于对照组,差异具有统计学意义(P<0.05)。观察组患者治疗后上肢Brunnstrom运动功能分期结果优于对照组,差异具有统计学意义(Z=–2.101,P <0.05)。观察组患者治疗后手Brunnstrom运动功能分期结果优于对照组,差异具有统计学意义(Z=–2.152,P <0.05)。结论:在恢复早期,头针、镜像疗法与常规康复训练有效结合,对脑卒中患者软瘫期上肢运动功能恢复具有积极作用。 相似文献
119.
Kyohei Itamura Arthur Wu Elisa Illing Jonathan Ting Thomas Higgins 《JMIR Public Health and Surveillance》2021,7(1)
BackgroundReal-time polymerase chain reaction using nasopharyngeal swabs is currently the most widely used diagnostic test for SARS-CoV-2 detection. However, false negatives and the sensitivity of this mode of testing have posed challenges in the accurate estimation of the prevalence of SARS-CoV-2 infection rates.ObjectiveThe purpose of this study was to evaluate whether technical and, therefore, correctable errors were being made with regard to nasopharyngeal swab procedures.MethodsWe searched a web-based video database (YouTube) for videos demonstrating SARS-CoV-2 nasopharyngeal swab tests, posted from January 1 to May 15, 2020. Videos were rated by 3 blinded rhinologists for accuracy of swab angle and depth. The overall score for swab angle and swab depth for each nasopharyngeal swab demonstration video was determined based on the majority score with agreement between at least 2 of the 3 reviewers. We then comparatively evaluated video data collected from YouTube videos demonstrating the correct nasopharyngeal swab technique with data from videos demonstrating an incorrect nasopharyngeal swab technique. Multiple linear regression analysis with statistical significance set at P=.05 was performed to determine video data variables associated with the correct nasopharyngeal swab technique.ResultsIn all, 126 videos met the study inclusion and exclusion criteria. Of these, 52.3% (66/126) of all videos demonstrated the correct swab angle, and 46% (58/126) of the videos demonstrated an appropriate swab depth. Moreover, 45.2% (57/126) of the videos demonstrated both correct nasopharyngeal swab angle and appropriate depth, whereas 46.8% (59/126) of the videos demonstrated both incorrect nasopharyngeal swab angle and inappropriate depth. Videos with correct nasopharyngeal swab technique were associated with the swab operators identifying themselves as a medical professional or as an Ear, Nose, Throat–related medical professional. We also found an association between correct nasopharyngeal swab techniques and recency of video publication date (relative to May 15, 2020).ConclusionsOur findings show that over half of the videos documenting the nasopharyngeal swab test showed an incorrect technique, which could elevate false-negative test rates. Therefore, greater attention needs to be provided toward educating frontline health care workers who routinely perform nasopharyngeal swab procedures. 相似文献
120.
Benedict Wei Jun Pang Shiou-Liang Wee Lay Khoon Lau Khalid Abdul Jabbar Wei Ting Seah Daniella Hui Min Ng Queenie Lin Ling Tan Kenneth Kexun Chen Mallya Ullal Jagadish Tze Pin Ng 《Journal of the American Medical Directors Association》2021,22(4):885.e1-885.e10
ObjectivesTo describe the normative values of sarcopenia among community-dwelling adults (≥21 years of age); compare the prevalence of sarcopenia using Asian Working Group for Sarcopenia criteria, 2014 (AWGS2014), Asian Working Group for Sarcopenia criteria, 2019 (AWGS2019), and European Working Group on Sarcopenia in Older People criteria, 2018 (EWGSOP2) guidelines; and identify factors associated with sarcopenia.DesignParticipants were recruited through random sampling. Sarcopenia assessments were performed using a dual-energy x-ray absorptiometry scan (muscle mass), handgrip test (muscle strength), and usual walking test (physical performance). Questionnaires were administered to evaluate lifestyle and cognition.Setting and ParticipantsIn total, 542 community-dwelling Singaporeans were recruited (21?90 years old, 57.9% women).MethodsWe assessed anthropometry, body composition, and questionnaire-based physical and cognitive factors, and estimated sarcopenia prevalence according to the AWGS2014, AWGS2019, and EWGSOP2 recommendations, and examined associations using logistic regression.ResultsAccording to AWGS2019, the Singapore population-adjusted sarcopenia prevalence was 13.6% (men 13.0%; women 14.2%) overall, and 32.2% (men 33.7%, women 30.9%) in those aged 60 years and above. The cut-offs derived from young adult reference group for low appendicular lean mass index were 5.28 kg/m2 for men and 3.69 kg/m2 for women (lower than AWGS recommended cut-off); for gait speed it was 0.82 m/s, (AWGS2019 recommended cut-off 1.0 m/s, AWGS2014 cut-off was 0.8 m/s); and for handgrip strength it was 27.9 kg/m2 for men and 16.7 kg/m2 for women (close to AWGS2019 recommendation). Age, sex, marital status, alcoholism, physical activity, body mass index, waist circumference, and global cognition were associated with sarcopenia (P < .05).Conclusions and ImplicationsThis is the first study to provide reference values of muscle mass, strength, and gait speed across the adult lifespan of Singaporeans. Using AWGS2019 criteria, sarcopenia is prominent in older age (32.2% in ≥60 years old), but it is already nontrivial (6.9%) among young and middle-age persons. Multidomain lifestyle modifications addressing muscle strength, cognition, and nutrition over the adult lifespan are important to delay the development of sarcopenia. 相似文献