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91.
虚拟仿真实验是一种现代信息化和智慧教学的重要方法,对高等医学院校教学质量的发展起到重要的推进作用。我们自主开发建设的“霍乱弧菌检测与防控虚拟仿真实验”,既弥补了因生物安全问题不能开展的实验教学,也解决了微生物学检验实验教学中存在的操作标准化问题。采用“三步进阶”混合教学模式,实现以“学生为中心”的师生互动模式,创建“设计性实验报告”,与育人元素有机结合,培育医学生的职业使命感。细化考核标准,实现过程性评价。探索课前启发铺垫、课中内化升华、课后巩固拓展混合式实验教学模式,有效提高学生的实验技能,实现知行合一、素能共育的教学目标。  相似文献   
92.
Simkania negevensis has been associated with bronchiolitis in infants and community-acquired pneumonia in adults. Reports of exposure to this microorganism are only available from Israel, North America and Western Europe. Currently, no standard method for diagnosis of S. negevensis infection has been established nor have prevalence rates been shown in Japan. For the first time we demonstrated the ability of the microimmunofluorescence (MIF) test to detect S. negevensis-specific immunoglobulin G and exposure to S. negevensis in Japan. The positive rate in healthy volunteers was 4.3% (25/588), with rates increasing with age. Results indicate the usefulness of the MIF test as a serological method for detecting S. negevensis-specific antibodies. A standard serological test for infection with S. negevensis is needed.  相似文献   
93.
目的探讨在高原服用三康胶囊对移居青年体力作业效率的影响.方法对进驻海拔3700 ml年的10名青年在服药前和服药15 d后分别用EGM-II型踏车功量计做坐位蹯车运动,初始负荷功率为50W,每3min递增50W,以60 r/min连续踏车至200w 3 min后终止.用直线回归法计算每位受试者的PWC170.结果服药前PWCl70为(234.63±16.68)W,服药后PWC170为(258.66±16.85)W,服药后较服药前PWG170明显增高,差异有非常显著性意义(P<0.01).结论服用三康胶囊能明显提高高原移居青年的心功能及做功效率.  相似文献   
94.
利用正交设计法对叉叶苏铁ISSR-PCR反应体系的优化研究   总被引:2,自引:1,他引:2  
比较CTAB法和SDS法提取叉叶苏铁(Cycas micholitzii)的总DNA,发现CTAB法是提取叉叶苏铁总DNA的较好方法;对叉叶苏铁ISSR-PCR反应体系中的4个主要因素dNTPs,Taq DNA聚合酶,引物及Mg2+进行最优条件筛选;采用单因素法探讨DNA模板量、退火温度和循环次数的最佳反应条件,建立了适合于叉叶苏铁的最佳ISSR-PCR反应体系 (20 μL体系): 1×Buffer,75 ng DNA模板,dNTPs 250 μmol·L-1, Taq酶1.0U,引物0.2 μmol·L-1,Mg2+ 2.5mmol·L-1,反应程序为:94℃预变性5 min,94℃变性1 min,52℃退火1 min,72℃延伸2 min,循环40次,72℃延伸10 min,4℃保存。本研究结果为苏铁纲植物的分子生物学和分子系统学研究提供理论参考。  相似文献   
95.
Apple replant disease (ARD) is common to all major apple-growing regions in the world. It occurs when new apple trees are replanted on sites where previously the same or closely related crop species were grown. Biotic (fungi, bacteria and nematodes) and abiotic soil factors (poor soil structure, nutrition) contribute to the development and severity of ARD. However, the aetiology of ARD and effects on higher trophic levels are still unknown. In that sense, Collembola might play an important role, since they are one of the dominant mesofauna groups in many soils. They act as decomposer, fungivores and predators, representing different trophic levels in soil food webs. Therefore, any effect of ARD on the occurrence of Collembola could have ecological impacts on the soil quality and health. Here, we examined the colonization behaviour of two Collembolan species, Folsomia candida and Sinella curviseta, in choice tests and population growth tests using Apple Replant Diseased soil (ARD) and non-ARD soil samples from different field sites and standardized laboratory bioassays. Additionally, Collembola behaviour was quantified by continuous video observations to investigate short-term behavioural changes. Results showed that both Collembolan species significantly preferred colonization of the non-ARD soils compared with ARD soils, independent of the origin of the soil samples or specific disinfection treatments. Moreover, the detailed video analysis of the foraging behaviour indicates rapid colonization of soil samples and low dispersal rates. Most likely, volatile compounds and to a lesser extent feeding stimulants play a vital role for the colonization process for both Collembolan species. Finally, results showed negative effects of ARD on population growth of both Collembolan species already after an 8-week period, implying strong nutritional deficiencies in ARD affected soils. The hypothesis that ARD causing microorganisms directly affected orientation, colonization and population development of Collembola is discussed.  相似文献   
96.
BackgroundTo examine changes in prostate cancer incidence and mortality rates, and 5-year relative survival, in relation to changes in the rate of prostate specific antigen (PSA) screening tests and the use of radical prostatectomy (RP) in the Australian population.MethodsProstate cancer stage-specific incidence rates, 5-year relative survival and mortality rates were estimated using New South Wales Cancer Registry data. PSA screening test rates and RP/Incidence ratios were estimated from Medicare Benefits Schedule claims data. We used multiple imputation to impute stage for cases with “unknown” stage at diagnosis. Annual percentage changes (APC) in rates were estimated using Joinpoint regression.ResultsTrends in the age-standardized incidence rates for localized disease largely mirrored the trends in PSA screening test rates, with a substantial ‘spike’ in the rates occurring in 1994, followed by a second ‘spike’ in 2008, and then a significant decrease from 2008 to 2015 (APC −6.7, 95% CI −8.2, −5.1). Increasing trends in incidence rates were observed for regional stage from the early 2000s, while decreasing or stable trends were observed for distant stage since 1993. The overall RP/Incidence ratio increased from 1998 to 2003 (APC 9.6, 95% CI 3.8, 15.6), then remained relatively stable to 2015. The overall 5-year relative survival for prostate cancer increased from 58.4% (95% CI: 55.0–61.7%) in 1981–1985 to 91.3% (95% CI: 90.5–92.1%) in 2011–2015. Prostate cancer mortality rates decreased from 1990 onwards (1990–2006: APC −1.7, 95% CI −2.1, −1.2; 2006–2017: APC −3.8, 95% CI −4.4, −3.1).ConclusionsOverall, there was a decrease in the incidence rate of localized prostate cancer after 2008, an increase in survival over time and a decrease in the mortality rate since the 1990s. This seems to indicate that the more conservative use of PSA screening tests in clinical practice since 2008 has not had a negative impact on population-wide prostate cancer outcomes.  相似文献   
97.
Informed consent is a key condition for prenatal screening programmes to reach their aim of promoting reproductive autonomy. Reaching this aim is currently being challenged with the introduction of non-invasive prenatal testing (NIPT) in first-trimester prenatal screening programmes: amongst others its procedural ease—it only requires a blood draw and reaches high levels of reliability—might hinder women’s understanding that they should make a personal, informed decision about screening. We offer arguments for a renewed recognition and use of informed consent compared to informed choice, and for a focus on value-consistent choices and personalized informational preferences. We argue for a three-step counselling model in which three decision moments are distinguished and differently addressed: (1) professionals explore women’s values concerning whether and why they wish to know whether their baby has a genetic disorder; (2) women receive layered medical-technical information and are asked to make a decision about screening; (3) during post-test counselling, women are supported in decision-making about the continuation or termination of their pregnancy. This model might also be applicable in other fields of genetic (pre-test) counselling, where techniques for expanding genome analysis and burdensome test-outcomes challenge counselling of patients.  相似文献   
98.
The effect of incubation and rearing temperature on muscle development and swimming endurance under a high-intensity swimming test was investigated in juvenile Chinook salmon (Oncorhynchus tshawytscha) in a hatchery experiment. After controlling for the effects of fork length (LF) and parental identity, times to fatigue of fish were higher when fish were incubated or reared at warmer temperatures. Significant differences among combinations of pre- and post-emergence temperatures conformed to 15–15°C > 15–9°C > 9–9°C > 7–9°C > 7–7°C in 2011 when swimming tests were conducted at 300 accumulated temperature units post-emergence and 15–9°C > (7–9°C = 7–7°C) in 2012 when swimming tests were conducted at an LF of c. 40 mm. The combination of pre- and post-emergence temperatures also affected the number and size of muscle fibres, with differences among temperature treatments in mean fibre cross-sectional area persisting after controlling for LF and parental effects. Nonetheless, neither fibre number nor fibre size accounted for significant variation in swimming endurance. Thus, thermal carryover effects on swimming endurance were not mediated by thermal imprinting of muscle structure. This is the first study to test how temperature, body size and muscle structure interact to affect swimming endurance during early development in salmon.  相似文献   
99.
目的建立肝性脑病(HE)动物模型。方法应用四氯化碳联合酒精自饮法制作慢性肝功能衰竭引起HE发生的模型,进行迷宫试验、脑电图、血液生化、形态学、行为活动观察等检测。结果 1.肉眼下可见模型组肝脏普遍肿大,表面较粗糙,有较粗的颗粒,暗红色;正常组肝脏未见异常。模型组肝内有大量纤维增生,肝细胞溶解,弥漫性大片坏死,残留肝细胞成片气球样变。2.与对照组大鼠比较,造模组第九周水迷宫测试逃避潜伏期明显延长,以潜伏期延长超过正常x+2.5 s为标准,本实验有14/20(55%)只大鼠水迷宫潜伏期明显延长;3.HE模型组血氨浓度明显高于正常对照组,组间比较差异有显著性(P〈0.01);4.正常组脑电图以α波为主,无明显异常;模型组出现肝性脑病变化。结论 1.建立了肝硬化合并肝性脑病较为理想的动物模型;2.水迷宫测试联合检测更易检出HE。  相似文献   
100.
The production conditions of the Gomphidius rutilus exopolysaccharides (GREP) in submerged culture were optimised, and the antioxidant activities of GREP in vitro were evaluated. The optimal culture medium constituents were determined as follows: 30 g/L sucrose, 3.0 g/L soybean meal, 0.25 g/L MgSO4, 1.5 g/L K2HPO4, 0.5 g/L KH2PO4, 0.03 g/L ZnSO4, and 0.01 g/L FeSO4. The optimum parameters for the liquid fermentation were as follows: temperature, 25 °C; cultivation time, 6 d; initial pH, 8.0; volume of medium, 150 mL; and rotary speed, 180 rpm. GREP content and dry cell weight in optimised conditions were 540.1 ± 15.9 mg/L and 8.2 ± 0.3 g/L, respectively. GREP content under the optimised conditions was 2.5 times than that under the basic culture medium and initial conditions. GREP demonstrated positive antioxidant potential on superoxide anion radical, 1,1-diphenyl-2-picrylhydrazyl, and hydroxyl radical scavenging, and reducing power.  相似文献   
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