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31.
Suchi Raghunathan Corey L. Reynolds Robert J. Schwartz M. David Stewart Bradley K. McConnell 《Fundamental & clinical pharmacology》2019,33(1):25-30
Inbred mouse strains are the most widely used mammalian model organism in biomedical research owing to ease of genetic manipulation and short lifespan; however, each inbred strain possesses a unique repertoire of deleterious homozygous alleles that can make a specific strain more susceptible to a particular disease. In the current study, we report dystrophic cardiac calcinosis (DCC) in C.B‐17 SCID male mice at 10 weeks of age with no significant change in cardiac function. Acquisition of DCC was characterized by myocardial injury, fibrosis, calcification, and necrosis of the tissue. At 10 weeks of age, 38% of the C.B‐17 SCID mice from two different commercial colonies exhibited significant calcinosis on the ventricular epicardium, predominantly on the right ventricle. The frequency of calcinosis was more than 50% for mice obtained from Taconic's Cambridge City colony and 25% for mice obtained from Taconic's German Town colony. Interestingly, the DCC phenotype did not affect cardiac function at 10 weeks of age. No differences in echocardiography or electrocardiography were observed between the calcinotic and non‐calcinotic mice from either colony. Our findings suggest that C.B‐17 SCID mice exhibit DCC as early as 10 weeks of age with no significant impact on cardiac function. This strain of mice should be cautiously considered for the study of cardiac physiology. 相似文献
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33.
杨永磊 《长春中医药大学学报》2015,(4):749-750
目的 观察参麦注射液治疗冠心痛的临床效果.方法 选取我院2013年4月-2014年1月间收治的冠心病患者94例,依据治疗方案不同分为治疗组48例,对照组46例,2组患者入院均根据病情给予能量合剂、血管扩张剂、减轻心脏负荷药物,并进行对症、溶栓及抗心律失常等常规治疗,治疗组患者在常规治疗的基础上给予参麦注射液静滴治疗,1次/d,用药2周为1疗程;于治疗2疗程后观察治疗效果,并对比2组患者临床症状、心电图改善情况及红细胞超氧化物歧化酶(E-SOD)平均活性,血浆过氧化脂质(P-LPO)、红细胞过氧化脂质(E-LPO)含量变化.结果 治疗组治疗后总有效率显著高于对照组(P<0.05);治疗组胸闷、心悸、心绞痛及ST段下移、T渡低平或倒置患者改善率显著均高于对照组(P<0.05);治疗组治疗后E-SOD活性显著高于对照组,P-LPO、E-LPO含量显著低于对照组(P<0.05).结论 参麦注射液可有效缓解冠心病患者临床症状,降低血中脂质过氧化物浓度,缓解心肌缺血状态. 相似文献
34.
Stuart J. Dilley Tracey J. Weiland Robert O’Brien Neil J. Cunningham Julian E. Van Dijk Rosie M. Mahoney 《Teaching and learning in medicine》2015,27(1):71-79
Theory: Immersive simulation is a common mode of education for medical students. Observation of clinical simulations prior to participation is believed to be beneficial, though this is often a passive process. Active observation may be more beneficial. Hypotheses: The hypothesis tested in this study was that the active use of a simple checklist during observation of an immersive simulation would result in better participant performance in a subsequent scenario compared with passive observation alone. Methods: Medical students were randomized to either passive or active (with checklist) observation of an immersive simulation involving cardiac arrest prior to participating in their own simulation. Performance measures included time to cardiopulmonary resuscitation (CPR) and time to defibrillation and were compared between first and second scenarios as well as between passive and active observers. Results: Seventy-nine simulations involving 232 students were conducted. Mean time to CPR was 18 seconds (SD = 11.6) for those using the checklist and 24 seconds (SD = 15.8) for those who observed passively (M difference = 6 seconds), t(35) = 1.46, p =.153. Time to defibrillation was 94 seconds (SD = 26.4) for those using the checklist and 92 seconds (SD = 23.8) for those who observed passively (M difference = –2 seconds), t(38) =.21, p =.837. Time to CPR was 24 seconds (SD = 15.8) for passive observers and 31 seconds (SD = 21.0; M difference = 7 seconds), t(35) = 1.13, p =.265, for their first scenario counterparts. Time to CPR was 18 seconds (SD = 11.6) for active observers and 36 seconds (SD = 26.2; M difference = 18 seconds), t(24) = 2.81, p =.010, for their first scenario counterparts. Time to defibrillation was 92 seconds (SD = 23.8) for passive observers and 125 seconds (SD = 32.2; M difference = 33 seconds), t(33) = 3.63, p =.001, for their first scenario counterparts. Time to defibrillation was 94 seconds (SD = 26.4) for the active observers and 132 seconds (SD = 52.9; M difference = 38 seconds), t(28) =.46, p =.008, for their first scenario counterparts. Conclusions: Observation alone leads to improved performance in the management of a simulated cardiac arrest. The active use of a simple skills-based checklist during observation did not appear to improve performance over passive observation alone. 相似文献
35.
目的 探讨非高密度脂蛋白胆固醇水平(non-HDL-C)与冠心病(CHD)患者冠状动脉病变Gensini评分的关系及临床意义。方法 对225例疑诊或既往临床诊断CHD患者予以冠状动脉造影(CAG),将造影阴性的39例作为对照组(HC组),造影阳性的186例患者诊断为CHD,结合临床特点分为心绞痛组(AP组)122例和心肌梗死组(AMI组)64例。采用Gensini评分对冠状动脉病变程度评分,测定患者全套血脂水平,探讨non-HDL-C及相关脂质成分与冠状动脉病变程度Gensini评分的相关性;同时对他汀类药物强化降脂达标,低密度脂蛋白胆固醇(LDL-C)<1.80 mmol/L的AP组患者进行non-HDL-C与冠状动脉病变程度Gensini评分的亚组分析。结果 AMI组non-HDL-C水平高于AP组及HC组,AP组non-HDL-C水平高于HC组,差异均有统计学意义(P<0.05);CHD患者non-HDL-C水平与Gensini评分呈正相关(r=0.562,P<0.05);LDL-C控制达标的AP组患者,高non-HDL-C组(≥2.60 mmol/L)比低non-HDL-C组(<2.60 mmol/L)Gensini评分明显升高,差异均有统计学意义(P<0.05)。结论 non-HDL-C与冠状动脉病变程度密切相关,non-HDL-C在评估LDL-C控制达标患者的冠状动脉病变程度及再发心血管事件风险上有一定价值,可作为LDL-C达标后心血管残余风险新的观察指标。 相似文献
36.
37.
《Ultrasound in medicine & biology》2015,41(12):3172-3181
Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy. 相似文献
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39.
《Patient education and counseling》2020,103(4):854-863
ObjectiveTo examine the effectiveness of a nurse-led multidisciplinary self-management program (NMSP) on self-management behaviors, self-efficacy, health-related quality of life (HRQoL) and unplanned health service utilization (HSU) among Chinese patients with coronary heart disease (CHD) in communities.MethodsA randomized controlled trial with repeated measurements was used. A convenience sample of 144 participants was recruited from a community health center in China. All participants were randomly assigned to an intervention group (n = 72) in the newly developed NMSP or a control group (n = 72) in routine care. Outcome measurement was performed at baseline, 3 months and 6 months using Coronary Artery Disease Self-Management Scale (CADSs), Self-efficacy for Chronic Disease 6-item Scale (SECD6), and Short Form-12 health survey questionnaire (SF-12).ResultsOver the six months, the two groups reported significant differences in disease medical and emotional management of CADSs, confidence in symptom and disease management of SECD6, physical and mental component summary of SF-12, as well as emergency and outpatient visits of unplanned HSU.ConclusionsThe NMSP improves self-management behaviors, self-efficacy, HRQoL and reduces unplanned HSU among CHD patients in communities.Practice implicationsThis study provides an effective approach to empower CHD patients with emphasizing on collaboration support of health professionals in communities. 相似文献
40.