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151.
针对目前大多数小型呼吸机中呼吸动力学参数监测模块功能较弱的现状,采用新型传感器和基于ARM核的微处理器,设计了一种新型呼吸机动力学参数监测模块。该模块提高了呼吸动力学参数检测的精度,满足了实时监测的需要。通过使用USB接口,既提供了模块供电电源又实现了即插即用功能,控制系统通过USB接口可实时设置测量模块各种参数,对测量功能进行灵活配置。测试结果表明该模块适用于呼吸机及ICU病房中呼吸动力学参数的监测。 相似文献
152.
红心大白菊挥发油成分的GC-MS分析 总被引:2,自引:4,他引:2
目的 :分析我国中药材GAP基地红心大白菊挥发油的化学成分 ,为其质量评价提供科学依据。方法 :采用水蒸气蒸馏法提取红心大白菊挥发油 ,用GC毛细管柱进行分析 ,归一化法测定其相对含量 ,并用GC-MS法鉴定化学成分。结果 :检出 136个色谱峰 ,鉴定出 47个化合物 ,占挥发油总量的 62.24%。结论 :红心大白菊挥发油中 ,雪松醇、喇叭醇和 1-(1,5-二甲基-4-己烯基 )-4-甲基苯是其主要成分 ,以倍半萜类化合物喇叭醇含量最高 ,占总挥发油量的 13.9%。 相似文献
153.
目的 :探讨我国维生素C制造业核心竞争力的发展途径。方法 :分析我国维生素C产业特点及在我国加入WTO后形成的新竞争态势 ;研究我国维生素C制造企业内部价值链。结果与结论 :发展新的核心竞争力应着重培育以创新为基本特征的企业价值链内核。 相似文献
154.
目的:克隆丝裂原活化蛋白激酶激酶6(mitogen-activated protein kinase kinase 6,MKK6)基因启动子,研究泛
素水解酶22(ubiquitin specific peptidase 22,USP22)对MKK6转录活性的调控作用。方法:采用PCR扩增MKK6基因启动
子片段,并以该片段为模板对USP22结合位点进行定点突变,将野生型与突变型启动子片段定向插入荧光素酶表达
载体pGL3-Basic;用重组载体与内参质粒pRL-TK共转染HeLa细胞,行双荧光素酶活性检测以确定其转录活性;利用
染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)实验观察USP22蛋白与MKK6启动子是否存在直接的结合;下
调USP22表达后,检测MKK6转录活性的变化。结果:成功扩增MKK6启动子及其突变体并构建荧光素酶表达载体;
USP22结合位点的突变导致该启动子活性在HeLa细胞中明显降低(P<0.05);USP22与MKK6启动子在细胞中存在直接结
合;抑制USP22的表达导致MKK6转录水平明显下降(P<0.05)。结论:在HeLa细胞中,USP22有效地调控MKK6基因的
转录。 相似文献
155.
目的探讨躯干核心肌群训练的强度对脑卒中患者躯干控制、平衡步行及日常生活能力的康复效果。方法选择2017年4月至2018年3月在华中科技大学同济医学院附属协和医院康复医学科住院治疗的90例脑卒中偏瘫患者为研究对象,按照随机数字表法将患者分为A、B、C组,每组各30例,3组患者均在常规治疗基础上联合不同强度的躯干核心肌群训练,其中A组每天训练1次,B组每天训练2次,C组每天训练3次,每次训练30 min,每周5天,共训练3个月。3组患者治疗1个月、2个月和3个月时采用躯干控制能力测试(TCT)、Berg平衡量表(BBS)评价躯干控制能力,采用步行功能评级(FAC)评定平衡步行功能、采用日常生活能力(MBI)评定日常生活能力。比较3组患者上述评分差异。结果治疗前3组患者躯干控制能力、平衡步行功能和生活能力评分比较差异无统计学意义(P> 0. 05),3组患者治疗1个月、2个月、3个月后躯干控制、平衡步行和日常生活能力评分均逐渐提高,差异均有统计学意义(P均<0. 05);且在1~3个月期间躯干控制和平衡能力评分C组高于B组,B组高于A组,差异均有统计学意义(P均<0. 05),但3个月时差异无统计学意义(P> 0. 05)。3组患者步行和日常生活能力在1个月期间组间差异无统计学意义(P> 0. 05),但1个月后C组较B组,B组较A组均有统计学意义(P均<0. 05)。结论强化躯干核心肌力量可以显著提高患者躯干控制、平衡步行和日常生活能力,缩短康复时间。 相似文献
156.
Polymorphisms in the upstream regulatory region of the HLA class II DQA1 gene are currently defined by 10 different alleles. Two of them carrying a Y-box mutation are associated with susceptibility to oligoarticular juvenile idiopathic arthritis (OA-JIA). We investigated allele-dependent differences in HLA-DQA1 gene expression in OA-JIA patients. In cells from affected joints compared to peripheral blood, gene expression of HLA-DRA as well as total HLA-DQA1 was significantly upregulated. Differential analyses of HLA-DQA1 allelic expression showed DQA1*02 and *04 to be comparatively increased. Intra-articular upregulation of HLA-DQA1 was predominantly observed for the OA-JIA associated allele HLA-DQA1*04. Nevertheless, the Y-box mutation of the disease-associated allele DQA1*0401 was not a common denominator for expression behaviour. 相似文献
157.
158.
《International journal of hygiene and environmental health》2014,217(8):839-844
BackgroundSigmoidal (S-shaped) dose–cancer incidence relationships are often observed in animal bioassays for carcinogenicity. Ultraviolet (UV) radiation is an established skin carcinogen. The aim of this study is to examine if S-shaped curves describe the relationship between solar UV doses and skin cancer incidences, and if such relationships can be used to estimate threshold levels of non-carcinogenic UV exposure, as well as maximal incidence rates.MethodsWe studied the incidence rate–annual erythema-effective UV dose relationship for squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and cutaneous melanoma (CM) among different Caucasian populations in Europe, Australia and New Zealand.ResultsOur analysis indicates that S-shaped associations describe the data well (P < 0.0001). The age-adjusted incidence rates for cases expected to be due to other causes than solar UV exposure (at zero UV dose) were found to be around 0.6, 9.7 and 4.0 per 100,000 for women in 1997–2007 for SCC, BCC and CM, respectively, and around 1.2, 14.3 and 2.6 per 100,000 for men. The analysis indicates that SCC, BCC and CM have maximal incidence of 361 ± 24, 1544 ± 49 and 36 ± 4 per 100,000 for women, and 592 ± 35, 2204 ± 109 and 50 ± 4 per 100,000 for men.ConclusionsBetween 89 and 95% of the annual CM cases, around 99.8% SCC and 99.4% BCC cases are caused by solar UV exposure. The analysis did not identify any “safe” UV dose below which the risk for skin cancer was absent. Avoidance of UV radiation has a potential to reduce the incidence of skin cancer in fair-skinned population. 相似文献
159.
M. Garg J. Collyer D. Dhariwal 《The British journal of oral & maxillofacial surgery》2018,56(4):327-331
Training in oral and maxillofacial surgery (OMFS) in the UK has undergone considerable changes during the last 10 years, and “core” surgical training has replaced “basic” surgical training. In 2014 a pilot “run-through” training programme from specialist training year one (ST1)-ST7 was introduced to facilitate early entry into the speciality. Run-through training guarantees that a trainee, after a single competitive selection process and satisfactory progress, will be given training that covers the entire curriculum of the speciality, whereas uncoupled training requires a second stage of competitive recruitment after the first one (for OMFS only) or two years of “core” training to progress to higher specialty training.The first two years of run-through training (ST1-ST2) are the same as for core surgical training. Dual-qualified maxillofacial aspirants and those in their second degree course are curious to know whether they should go for the uncoupled core surgical training or the run-through programme in OMFS. The General Medical Council (GMC) has now agreed that run-through training can be rolled out nationally in OMFS. To assess the two pathways we used an online questionnaire to gain feedback about the experience from all OMFS ST3 and run-through trainees (ST3/ST4) in 2016–2017. We identified and contacted 21 trainees, and 17 responded, including seven run-through trainees. Eleven, including five of the run-through trainees, recommended the run-through training programme in OMFS. Six of the seven run-through trainees had studied dentistry first. The overall mean quality of training was rated as 5.5 on a scale 0–10 by the 17 respondents. This survey gives valuable feedback from the current higher surgical trainees in OMFS, which will be useful to the GMC, Health Education England, OMFS Specialist Advisory Committee, and those seeking to enter higher surgical training in OMFS. 相似文献
160.
《International journal of audiology》2013,52(8):497-506
AbstractObjective: To identify relevant aspects of functioning, disability, and contextual factors for adults with hearing loss (HL) from hearing health professional perspective summarized using the ICF classification as reference tool. Design: Internet-based cross-sectional survey using open-ended questions. Responses were analysed using a simplified content analysis approach to link concept to ICF categories according to linking rules. Study sample: Hearing health professionals (experts) recruited through e-mail distribution lists of professional organizations and personal networks of ICF core set for hearing loss steering committee members. Stratified sampling according to profession and world region enhanced the international and professional representation. Results: Sixty-three experts constituted the stratified sample used in the analysis. A total of 1726 meaningful concepts were identified in this study, resulting in 209 distinctive ICF categories, with 106 mentioned by 5% or more of respondents. Most categories in the activities & participation component related to communication, while the most frequent environmental factors related to the physical environment such as hearing aids or noise. Mental functions, such as confidence or emotional functions were also frequently highlighted. Conclusions: More than half (53.3%) of the entire ICF classification categories were included in the expert survey results. This emphasizes the importance of a multidimensional tool, such as the ICF, for assessing persons with hearing loss. 相似文献