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51.
An experimental animal hypoxia model has been developed. It consists of two sensors (an in vitro and in vivo model), an experimental device and a computer signal processing system. This method can easily be applied to determine and analyse blood oxygen saturation at various hypoxia levels. It can also be used to evaluate the accuracy of pulse oximetry over a wide range of oxyhemoglobin desaturation levels. The DC and AC components of recorded red and infra-red signals, the dual-wavelength ratio R12 and the reading of a pulse oximeter (SpO2) can be automatically calculated and displayed on a computer screen. Preliminary results of the animal hypoxia test indicate that the measurements made by the instrument correlate well with the oxygen saturation readings of the automatic blood gas analyser AVL945. The computer analysis system is suitable for repeated estimations in the animal model.  相似文献   
52.
胸部体表导纳变化与胸腔中血管导纳变化的关系   总被引:1,自引:1,他引:1  
目的:探讨胸部体表导纳变化与胸腔中血管导纳变化的关系。方法:根据导纳与阻抗互为倒数的关系,导出胸部体表导纳变化公式,并用模型实验证明。结果:单根血管在胸部体表引起的导纳变化与血管本身的导纳变化和基础导纳的比值成正比,与血管的长度和胸部体表两检测电极之间的基础导纳成正比,与血管到两检测电极连线的距离成反比;多根血管在胸部体表共同引起的导纳变化等于各血管单独在胸部体表产生的导纳变化的代数和,即在电导纳图测量中导纳变化遵从标量迭加原理。结论:本文结果可为心导纳图的波形重建奠定理论基础。  相似文献   
53.
CLINICALSIMULATEDEXPERIMENTONTHESYNDROMISTANDARDSOFPULMONARYSYSTEMDISEASESMulinXuQiouqinWang(HubeiAcademyofTraditionalChinese...  相似文献   
54.
目的研究不同给药方式对实体肿瘤抗癌药物疗效的影响,并通过动物实验验证。方法分别建立体内药代动力学和肿瘤内药物输运的集中参数模型,模拟单次快速注射和等时间间隔三次快速注射时肿瘤间质组织药物浓度Ct随时间的变化。实验小鼠分为两组,分别进行抗癌药羟基喜树碱(HCPT)单次快速注射和等时间间隔3次快速注射,观察其肿瘤内药物平均浓度。对数值模拟结果和动物实验结果进行比较。结果数值模拟结果显示,对于相同总量药物,等量等间隔的三次给药,肿瘤间质组织药物浓度Ct高于单次给药。动物实验的实测结果相同。结论3次给药的效果显著优于单次给药。集中参数模型基本能够定量反映不同给药方式的效果。  相似文献   
55.
兔激素性股骨头坏死的血液流变学改变   总被引:3,自引:0,他引:3  
目的 探讨血液流变学指标在激素性股骨头坏死过程中的变化规律及其作用。方法 20只兔随机分成2组,每组10只。A组(激素性股骨头坏死动物模型组):间隔24h耳缘静脉内2次注射大肠杆菌内毒素,每次40μg/kg,注射内毒素后注射醋酸泼尼松龙20mg/kg。B组(正常对照组)。两组分别在注射后24h、72h、7d、14d 及21d,进行血浆黏度、全血黏度、血小板计数及血脂测定,21d取股骨头和肝脏行病理组织学观察。结果 A组用药后24h血浆黏度、全血黏度升高,血脂升高(P<0.01)血小板计数减少(P<0.01),用药后72h、7d、14d 及21d,持续异常,与B组相比差异显著。A组21d时病理切片见股骨头骨细胞和肝细胞变性、坏死。结论 在激素性股骨头坏死动物模型中,血液流变学指标异常在引起血栓前状态,形成血栓导致骨坏死过程中可能发挥了重要作用。  相似文献   
56.
幼儿攻击性行为游戏矫正的倒返设计研究   总被引:2,自引:0,他引:2  
目的:探讨幼儿集体游戏用于矫正幼儿攻击性行为的效果。方法:采用倒返实验,对三名被试进行了游戏矫正。结果:三名被试在实验的基线阶段有明显的攻击性行为,游戏介入后攻击性行为明显减少,游戏取消后攻击性行为再度增加,游戏再次介入后,攻击性行为再次明显减少;方差检验的结果表明,被试在基线阶段的攻击性行为与游戏矫正后的攻击性行为差异极显著。结论:运用自然的幼儿集体游戏可以矫正幼儿的攻击性行为。  相似文献   
57.
呼吸功能不全综合实验改革的探索   总被引:3,自引:0,他引:3       下载免费PDF全文
目的:为了探索如何在一次教学实验中将生理学、病理生理学和药理学三个机能学科的实验有机地结合起来, 形成综合性实验以培养学生的综合思维和实验研究能力。方法:在病理生理学的呼吸功能不全实验的基础上, 增加了呼吸的生理调节和不同类型的呼吸衰竭采用不同的针对性药物治疗, 并且采用启发式教学方法。结果:学生学习兴趣明显提高, 学生不仅学到了更多的研究方法, 而且综合分析和科研创新能力都有明显提高。结论:这种改进明显提高了实验课的教学水平和教学质量。  相似文献   
58.
Front of pack food labels (FOPLs) provide accessible nutritional information to guide consumer choice. Using an online experiment with a large representative British sample, we aimed to examine whether FOPLs improve participants’ ability to identify the healthiness of foods and drinks. The primary aim was to compare ability to rank between FOPL groups and a no label control. Adults (≥18 years), recruited from the NatCen panel, were randomised to one of five experimental groups (Multiple Traffic Light, MTL; Nutri-Score, N-S; Warning Label, WL; Positive Choice tick, PC; no label control). Stratification variables were year of recruitment to panel, sex, age, government office region, and household income. Packaging images were created for three versions, varying in healthiness, of six food and drink products (pizza, drinks, cakes, crisps, yoghurts, breakfast cereals). Participants were asked to rank the three product images in order of healthiness. Ranking was completed on a single occasion and comprised a baseline measure (with no FOPL), and a follow-up measure including the FOPL as per each participant’s experimental group. The primary outcome was the ability to accurately rank product healthiness (all products ranked correctly vs. any incorrect). In 2020, 4504 participants had complete data and were included in the analysis. The probability of correct ranking at follow-up, and improving between baseline and follow-up, was significantly greater across all products for the N-S, MTL and WL groups, compared to control. This was seen for only some of the products for the PC group. The largest effects were seen for N-S, followed by MTL. These analyses were adjusted for stratification variables, ethnicity, education, household composition, food shopping responsibility, and current FOPL use. Exploratory analyses showed a tendency for participants with higher compared to lower education to rank products more accurately. Conclusions: All FOPLs were effective at improving participants’ ability to correctly rank products according to healthiness in this large representative British sample, with the largest effects seen for N-S, followed by MTL.  相似文献   
59.
ObjectivesTo determine what information is most important to registered nurses' (RNs) decisions to call clinicians about suspected urinary tract infections (UTIs) in nursing home residents.DesignWeb-based discrete choice experiment with 19 clinical scenarios.Setting and ParticipantsOnline survey with a convenience sample of RNs (N = 881) recruited from a health care research panel.MethodsClinical scenarios used information from 10 categories of resident characteristics: UTI risk, resident type, functional status, mental status, lower urinary tract status, body temperature, physical examination, urinalysis, antibiotic request, and goals of care. Participants were randomized into 2 deliberation conditions (self-paced, n = 437 and forced deliberation, n = 444). The degree to which evidence- and non–evidence-based information was important to decision-making was estimated using unconditional multinomial logistic regression.ResultsFor all nurses (22.8%) and the self-paced group (24.1%), lower urinary tract status had the highest importance scores for the decision to call a clinician about a suspected UTI. For the forced-deliberation group, body temperature was most important (23.7%), and lower urinary tract status was less important (21%, P = .001). The information associated with the highest odds of an RN calling about a suspected UTI was painful or difficult urination [odds ratio (OR) 4.85, 95% confidence interval (CI) 4.16–5.65], obvious blood in urine (OR 4.66, 95% CI 3.99–5.44), and temperature at 101.5° (OR 3.80, 95% CI 3.28–4.42). For the self-paced group, painful or difficult urination (OR 5.65, 95% CI 4.53–7.04) had the highest odds, whereas obvious blood in urine (OR 4.39, 95% CI 3.53–5.47) had highest odds for the forced-deliberation group.Conclusions and ImplicationsThis study highlighted the importance of specific resident characteristics in nurse decision-making about suspected UTIs. Future antimicrobial stewardship efforts should aim to not only improve the previously studied overprescribing practices of clinicians, but to improve nurses' assessment of signs and symptoms of potential infections and how they weigh resident information.  相似文献   
60.
目的探讨在产科护理教学中应用正常分娩综合性实验教学取得的效果研究。方法选取2018年9月—2019年6月在该院实习120名护理本科生作为研究对象,依据奇数偶数分配原则分为两组,其中对照组60名学生进行常规的消毒操作和外阴清洁考核,观察组的60名学生应用正常分娩综合性实验进行考核,对比两组学生护理技能测试成绩以及取得的教学效果。结果观察组优良率(98.33%)高于对照组(88.33%),差异有统计学意义(P<0.05);观察组团队协作能力、学习兴趣、解决问题能力、沟通能力及操作能力评分高于对照组,差异有统计学意义(P<0.05)。结论产科护理教学中应用正常分娩综合性实验教学取得的效果显著,能提升教学成绩,让实习护理本科生更快掌握护理技巧,为医院输送优质护理人才,能缓解产科护理人员缺乏的现象,正常分娩综合性实验教学方案值得应用。  相似文献   
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