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61.
吴卫辉  潘皎 《微生物学通报》2020,47(4):1095-1099
目前在全球化形势下,推进全英文教学对于国际合作与交流至关重要。但是如何让全英文教学不流于形式,使其能与提高教学质量充分结合、相辅相成,从而使全英文教学真正起到传授知识、搭建科学体系、提升学生兴趣、引领科学思维及知识应用的目的,值得探究。在近几年来的教学过程中,我们采用循序渐进的方式,从专业基础课"微生物学"的双语教学,推进至专业选修课"微生物遗传学"的全英文教学。在教学内容上,由浅入深,由面至点,将基础知识与实验技术贯通讲解;在教学方法和手段上,充分运用课上测验、课后作业与课上分析讨论等多种形式,达到了全英文授课与提升学生注意力、灵活运用知识能力相结合的目的。经过几年的不断探索与实践,全英文授课调动了学生积极参与和主动学习的热情,使学生在充分掌握课堂内容的基础上,锻炼了使用英文进行学习、探索、解决问题和交流的能力。学生学习兴趣和热情的激发也检验了全英文的教学效果。  相似文献   
62.
以山女鳟(Oncorhynchus masou masou)群体中出现的银化体色个体为研究对象,系统研究了在人工养殖条件下银化体色个体在群体中所占比率、银化体色个体与正常体色个体的体色差异,以及银化体色个体生长性状等.结果表明:①群体中不同家系间银化体色个体所占比率在O~0.21范围内,采用3×2列联表法进行卡方检验,...  相似文献   
63.
王易  刘丹  王莉新 《微生物学通报》2011,38(11):1718-1720
细菌的结构是病原生物学课程教学中最为基础的教学内容.随着科学技术和研究方法的发展,人们对细菌结构的认识也愈加深入.对国内教材普遍采用的细菌“特殊结构”概念提出不同的观点,试与同行切磋探讨.  相似文献   
64.
We propose and test a method to determine the proportion of specific animal national populations included in a network of protected areas. The proposed method further allows identifying the best potential new sites to be included in the network, to reach target population sizes and so to test whether a network extension is realistic or not. We used data from the French Breeding Bird Survey (BBS) and spatial interpolation models known as kriging to predict the relative abundance of species at a national scale. We applied the proposed methodology to Special Protection Areas (SPAs) and a sample of 20 bird species concerned by the Directive of the Council of the European Community on the Conservation of Wild Birds. We estimated which relative part of the national population is included within the boundaries of all national SPAs. Our results suggest that the current SPA network is probably not efficient to ensure favorable national conservation status for the most widespread species, but allows reaching a 5% target value for more localized ones. Consequently, we discuss the limit of such a protected area network to ensure the global conservation of widespread species, and therefore the need for other large-scale conservation measures.  相似文献   
65.
Trait diversity is believed to influence ecosystem dynamics through links between organismal traits and ecosystem processes. Theory predicts that key traits and high trait redundancy—large species richness and abundance supporting the same traits—can buffer communities against environmental disturbances. While experiments and data from simple ecological systems lend support, large‐scale evidence from diverse, natural systems under major disturbance is lacking. Here, using long‐term data from both temperate (English Channel) and tropical (Seychelles Islands) fishes, we show that sensitivity to disturbance depends on communities’ initial trait structure and initial trait redundancy. In both ecosystems, we found that increasing dominance by climatically vulnerable traits (e.g., small, fast‐growing pelagics/corallivores) rendered fish communities more sensitive to environmental change, while communities with higher trait redundancy were more resistant. To our knowledge, this is the first study demonstrating the influence of trait structure and redundancy on community sensitivity over large temporal and spatial scales in natural systems. Our results exemplify a consistent link between biological structure and community sensitivity that may be transferable across ecosystems and taxa and could help anticipate future disturbance impacts on biodiversity and ecosystem functioning.  相似文献   
66.
While the population growth rate in long‐lived species is highly sensitive to adult survival, reproduction can also significantly drive population dynamics. Reproductive parameters can be challenging to estimate as breeders and nonbreeders may vary in resighting probability and reproductive status may be difficult to assess. We extended capture–recapture (CR) models previously fitted for data on other long‐lived marine mammals to estimate demographic parameters while accounting for detection heterogeneity between individuals and state uncertainty regarding reproductive status. We applied this model to data on 106 adult female bottlenose dolphins observed over 13 years. The detection probability differed depending on breeding status. Concerning state uncertainty, offspring were not always sighted with their mother, and older calves were easier to detect than young‐of‐the‐year (YOY), respectively, 0.79 (95% CI 0.59–0.90) and 0.58 (95% CI 0.46–0.68). This possibly led to inaccurate reproductive status assignment of females. Adult female survival probability was high (0.97 CI 95% 0.96–0.98) and did not differ according to breeding status. Young‐of‐the‐year and 1‐year‐old calves had a significantly higher survival rate than 2‐year‐old (respectively, 0.66 CI 95% 0.50–0.78 and 0.45 CI 95% 0.29–0.61). This reduced survival is probably related to weaning, a period during which young are exposed to more risks since they lose protection and feeding from the mother. The probability of having a new YOY was high for breeding females that had raised a calf to the age of 3 or lost a 2‐year‐old calf (0.71, CI 95% 0.45–0.88). Yet, this probability was much lower for nonbreeding females and breeding females that had lost a YOY or a 1‐year‐old calf (0.33, 95% CI 0.26–0.42). The multievent CR framework we used is highly flexible and could be easily modified for other study questions or taxa (marine or terrestrial) aimed at modeling reproductive parameters.  相似文献   
67.
目的:探讨宫颈特殊染色法(FRD)、液基薄层细胞学(TCT)及人乳头瘤病毒(HPV)检测对宫颈癌前病变筛查的应用价值。方法:选取2015年1月~2018年1月于我院行宫颈癌筛查的1794例妇女作为研究对象,所有研究对象均接受FRD、TCT、HPV检测,以经阴道镜取样活检结果为阳性标准,对比分析三种不同检测方法以及联合检测的诊断效能。结果:病理科活检检出阳性111例,检出率为6.19%;FDR检测检出阳性114例,检出率为6.35%,漏诊率为16.22%;TCT检测检出阳性115例,检出率为6.41%,漏诊率为19.82%;HPV检测检出阳性108例,检出率为6.02%,漏诊率为19.82%;FRD检测与TCT、HPV检测的检出率比较差异无统计学意义(P0.05)。FRD检测敏感度为83.78%,特异度为98.75%,阳性预测值为81.58%,阴性预测值为98.93%;TCT检测敏感度为80.18%,特异度为98.46%,阳性预测值为77.39%,阴性预测值为98.69%;HPV检测敏感度为80.18%,特异度为98.87%,阳性预测值为82.41%,阴性预测值为98.70%;FRD、TCT、HPV联合检测敏感度为93.69%,特异度为99.52%,阳性预测值为92.86%,阴性预测值为99.58%;FRD、TCT、HPV联合检测与FRD、TCT、HPV单独检测的敏感度、阳性预测值比较差异具有统计学意义(P0.05)。结论:FRD、TCT、HPV检测对宫颈癌前病变的诊断效能相当,而FRD、TCT、HPV联合检测的诊断效能优于各方法单独检测。  相似文献   
68.
《生物化学与分子生物学基础》既是一门重要的专业课,又指向发展迅速的前沿科研领域。四年的全英教学实践通过采用英文原版教材、英文授课、课堂问答测验、作业、文献阅读与研讨、代谢通路的戏剧表演等方式丰富了课程的教学内容,使考核评价体系多样化,既激发了学生的学习兴趣,又培养了他们的学术素养和综合能力。教学方法的改进提高了教学质量,形成了受学生好评、教学效果良好、有特色的全英教学模式。  相似文献   
69.
目的:通过分析抗菌药物临床应用专项治理前后住院患者抗菌药的使用情况,以促进合理用药。方法:随机抽取我院2010年1至2011年12月病例1680份,抽取甲状腺/乳腺/疝气/闭合性骨折I类切口手术病历100份,分析治理前后抗菌药物使用率、使用强度、病原送检率、DDDs、DUI及I类切口抗菌药物应用情况。结果:治理前住院患者抗菌药物使用率、使用强度分别为68.50%、49.8DDD;治理后分别为56.2%、37.8DDD,显著降低(P<0.05)。治理前有四种抗菌药物DUI>1,依次为头孢哌酮/舒巴坦钠>头孢噻吩钠=头孢唑啉>头孢呋辛;治理后有两种抗菌药物DUI>1,依次为磺苄西林>头孢哌酮/舒巴坦钠;治理后I类切口手术患者预防使用抗菌药物比例略为下降,疗程符合率、用药合理率明显上升(P<0.05)。结论:我院住院患者抗菌药使用情况基本达到《抗菌药物临床应用专项工作方案》要求。但在某些方面,如I类切口使用率、疗程、用药选择上需要持续改进,应加强对I类切口的监管力度,以确保用药的经济、有效、合理。  相似文献   
70.
The phytoplankton composition was investigated at two fixed stations in the north-eastern English Channel from November 1997 to December 2005. The warmest temperatures in European historical records were recorded in August 2003. This event was associated with an exceptional abundance peak of the dinoflagellates Akashiwo sanguinea (9600 cells L(-1)) and Ceratium fusus. The lowest February temperatures for the 1998-2005 period were recorded in 2005, coinciding with the absence, for the first time in recent decades, of the spring bloom of Phaeocystis globosa. The 'de-eutrophication', mainly the reduction of river nutrient loads, is progressively reducing the magnitude of the Phaeocystis blooms. Exceptionally in 2005, the colder temperatures increased water column mixing, favouring the dominance of tychoplanktonic diatoms until early March (pre-bloom period). The delay in spring stratification, lower light availability due to turbidity (resuspended sediment) and organic matter, and competition with tychoplanktonic diatoms contributed to retard the timing of the spring phytoplankton bloom and disadvantage the development of Phaeocystis. The summer 2003 European heat wave is expected to have had little influence on total annual primary production, because it occurred at mid-summer, the period of lowest annual phytoplankton abundance. However, the anomalous weather in the second half of winter 2005 did affect the annual primary production.  相似文献   
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