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41.
目的 通过与LBL教学法对比,探讨PBL教学法在核医学科课间实习教学中的应用效果.方法 选取哈尔滨医科大学2016级临床医学专业本科二班学生72人,随机分为实验组和对照组,每组各36人,在课间实习教学中分别实施PBL教学法和LBL教学法.实习结束后,通过考试及问卷调查,进行教学法评价.结果 观察组在考试成绩、学习兴趣、学习热情、教学满意度、培养临床思维、增强知识点掌握等教学法评价指标均优于对照组,具有统计学意义(P<0.05).结论 与LBL教学法相比,PBL教学法应用于核医学科课间实习教学中更能激发学生学习兴趣、增强综合素质,从而提高教学效果. 相似文献
42.
Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献43.
44.
Ewelina Kazimierczyk Andrzej Eljaszewicz Paula Zembko Ewa Tarasiuk Malgorzata Rusak Agnieszka Kulczynska-Przybik Marta Lukaszewicz-Zajac Karol Kaminski Barbara Mroczko Maciej Szmitkowski Milena Dabrowska Bozena Sobkowicz Marcin Moniuszko Agnieszka Tycinska 《Pharmacological reports : PR》2019,71(1):73-81
Background
Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.Methods
In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.Results
AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.Conclusions
These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium. 相似文献45.
《Journal of pharmaceutical sciences》2019,108(7):2500-2504
Accurately predicting the hepatic clearance of compounds using in vitro to in vivo extrapolation (IVIVE) is crucial within the pharmaceutical industry. However, several groups have recently highlighted the serious error in the process. Although empirical or regression-based scaling factors may be used to mitigate the common underprediction, they provide unsatisfying solutions because the reasoning behind the underlying error has yet to be determined. One previously noted trend was intrinsic clearance-dependent underprediction, highlighting the limitations of current in vitro systems. When applying these generated in vitro intrinsic clearance values during drug development and making first-in-human dose predictions for new chemical entities though, hepatic clearance is the parameter that must be estimated using a model of hepatic disposition, such as the well-stirred model. Here, we examine error across hepatic clearance ranges and find a similar hepatic clearance-dependent trend, with high clearance compounds not predicted to be so, demonstrating another gap in the field. 相似文献
46.
目的 探究黄石、荆门地区产后妇女母乳喂养自我效能的现状及影响因素,为改善母乳喂养率提供更多理论依据。方法 对2017年12月—2018年3月在湖北省黄石市、荆门市的三所医院住院分娩的产妇进行问卷调查,获得产妇社会人口特征、孕产相关资料、母乳喂养相关情况。采用多元线性回归分析母乳喂养自我效能的影响因素。结果 共1 023名产妇纳入分析,平均年龄(29.0±5.7)岁。已婚占98.3%,初产占54.0%,大专及以上学历占53.9%。研究对象的母乳喂养自我效能平均得分为(45.5±12.3)分。多元线性回归的结果显示:当前不存在乳腺问题(B=2.08,P=0.036)、有母乳喂养经历(B=3.62,P<0.001)、家人提供母乳喂养指导或经验(B=3.20,P=0.001)、丈夫支持母乳喂养(B=5.87,P=0.001)及产后30 min内有医护母乳喂养帮助(B=3.02,P=0.003)的产妇母乳喂养自我效能得分更高。结论 产后妇女的母乳喂养自我效能可能与其健康状况、母乳喂养经历、社会支持及母乳喂养卫生服务有关。应对产后妇女提供广泛的社会支持,加强母乳喂养卫生服务提供,以提高其母乳喂养的自我效能,促进母乳喂养。 相似文献
47.
《Transfusion and apheresis science》2020,59(1):102608
Serum eye drops (SED) have shown beneficial effects in patients suffering from dry eye syndrome and are manufactured for an increasing number of patients in Australia every year. Previous studies have examined the stability of serum growth factors during storage in either experimental vessels not used as the final packaging system or in eye drop bottles. To ensure the quality and safety of SED product manufactured in Australia, the stability of growth factors in serum packaged into two different systems during storage at different temperatures was examined. Healthy blood donors provided a whole blood donation, from which serum was prepared, diluted to 20% and dispensed into either a tube or a vial packaging system. The stability of growth factors, fibronectin and total protein in tube segments was comparable to matched vials samples during storage at −30 °C, 4 °C, 22 °C and 37 °C, with the exception of EGF and fibronectin in 20% SED stored in tube segments, which were more sensitive to storage conditions at 4 °C and 22 °C when compared to vials. Additionally, the growth factor, fibronectin and total protein concentration in both tube segments and vials was stable during storage at −30 °C for at least 9 months. This study highlights the impact of different manufacturing procedures on serum growth factor stability during storage. 相似文献
48.
49.
目的调查嘉兴市新居民儿童心理发育行为问题及影响因素,为改善新居民儿童心理健康提供理论依据。方法随机抽取新居民儿童548例,本地儿童1248例,采用自编量表评估儿童家庭影响因素,长处与困难问卷评估儿童心理发育行为问题,心理痛苦温度计评估主观心理痛苦程度,儿童心理虐待与忽视量表评估家庭教养方式,社会支持量表评估社会支持程度。结果新居民儿童主观评定心理痛苦程度高于本地儿童(P=0.002)。新居民儿童亲社会化行为低于本地儿童(P=0.000),多动/注意缺陷问题高于本地儿童(P=0.011)。儿童忽视虐待量表本地儿童5个因子得分低于新居民儿童:责骂因子(P=0.000)、恐吓因子(P=0.000)、情感忽视因子(P=0.000)、教育忽视因子(P=0.000)、身体忽视因子(P=0.000)。社会支持量表本地儿童3个因子得分均高于新居民儿童:客观支持(P=0.032)、主观支持(P=0.000)、对支持的利用度(P=0.000)。新居民儿童在新居民儿童学校、混合学校、本地儿童学校的3类学校中亲社会化行为、忽视因子、虐待因子、社会支持均有统计学差异(均P<0.05)。结论新居民儿童较本地儿童心理发育行为明显落后,良好的家庭教养方式和有效的社会支持系统能够更快更好地促进其身心发育。 相似文献
50.