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1.
    
“Bryndza” is a traditional Slovak dairy product (type of soft cheese) made from sheep cheese which was ripened for 14 days. Because its manufacture, transporting and/or storing represent conditions which facilitate contamination, the effect of enterocin CCM4231 in “bryndza” was investigated with the aim to reduce the contaminant agents. “Bryndza” was divided into equal portions (50 g). The experimental sample (ES) as well as the control sample one (C1) were inoculated with Listeria innocua Li1 strain. The other control samples C2 and C3 were without Li1 strain. C3 control was selected as a reference control. ES and C2 portions were treated with purified enterocin CCM4231 in a concentration of 6400 AU/ml. Before the experimental inoculation, “bryndza” was checked for the presence of contaminant agents. The experiment lasted 1 week and the samples were stored in the refrigerator at 4 °C. Sampling was performed on day 1, on day 4 and on day 7. The control samples C2 and C3 were checked only on day 1 and then after 1 week. The following contaminant agents were detected in “bryndza” before its experimental inoculation with L. innocua Li1 strain: Escherichia coli in the amount 103 cfu/ml/g, Staphylococcus aureus (102 cfu/ml/g) and enterococci (104 cfu/ml/g). In the control sample C2, the number of E. coli was reduced to 102 cfu/ml/g. Enterococci and staphylococci were totally eliminated there. Concerning C3 control, natural decrease of bacteria was found and/or their unchanged counts. The value of pH (5) was stable during the whole experiment. In the experimental sample inoculated with Li1 strain, its counts were decreased immediately after enterocin CCM4231 addition approximately by one order of magnitude. This inhibitory effect was also detectable on day 4 by the difference of one order of magnitude between ES and C1. On day 7, 103 cfu/ml/g of Li1 strain were detected in both samples (ES, C1). The difference by one order of magnitude indicated, an inhibitory effect of enterocin CCM4231 in “bryndza”. However, bacteriocin activity was not determined by laboratory analyses.  相似文献   
2.
Large quantities of plants are traded annually in South Africa's traditional medicine or ‘muthi’ markets. A resource in high demand in the Faraday (Johannesburg) and Warwick (Durban) markets is uMavumbuka, a root holoparasite usually identified as either Hydnora africana Thunb. or Sarcophyte sanguinea Sparrm. subsp. sanguinea. However, rhizomes regularly observed in Faraday between 1994 and 2008 did not resemble either species, thereby suggesting that a third, and undocumented, species was being harvested. This was confirmed when the rhizomes were identified as H. abyssinica A.Br. by an American parasitic plant expert. An ethno-ecological study was initiated to verify its occurrence in selected muthi markets. The study further aimed to investigate the distribution of H. abyssinica through trader interviews, host species localities and some previously misidentified herbarium specimens. The study revealed that H. abyssinica was the only uMavumbuka species present in Faraday and Warwick in 2009. Furthermore, the rhizomes were being harvested in KwaZulu-Natal—an area not previously known to be part of its distribution range. Re-evaluated herbarium vouchers and recent photographs taken in the Kruger National Park have confirmed that H. abyssinica occurs in KwaZulu-Natal, Limpopo, Mpumalanga, Gauteng and Swaziland and hence eastern southern Africa. Fragments of Acacia xanthophloea Benth. roots were identified on 93% of the samples that had host roots attached, and we suspect that H. abyssinica follows the distribution of A. xanthophloea in suitable habitats north from KwaZulu-Natal and adjoining the South African border with Swaziland and Mozambique. Acacia karroo Hayne and A. grandicornuta Gerstner have also been positively identified as host species in South Africa from herbarium records. Plant harvesters in the markets cited the common names of several other species that uMavumbuka “grows under” that may be identified as hosts to H. abyssinica in the future. The collection of specimens in areas identified by the harvesters and in areas of suitable habitat is important to verify the occurrence, distribution and habitat of H. abyssinica in eastern southern Africa.  相似文献   
3.
    
The traditional medicine based on medicinal plants in the Kingdom of Arabia Saudia presents a strong relationship belonging to natural remedies, health, diet, and folk healing practice recognized by a specific culture. The aim of the current study is to carry out an ethnobotanical review on medicinal plants used in traditional medicine in the Kingdom of Arabia Saudia including information on plant species, used parts, preparation method as well as medical uses. Earlier published data in journals, textbooks, periodicals, websites, and databases written in pharmacological evidence of Suadi medicinal plants were based on gathering information. The present review work reported that 96 species belonging to 47 families have been used in Saudi Pharmacopeia. Amaranthaceae has the highest number of plant species (7) Followed by Asteraceae, Apocynaceae, and Fabaceae with 5 plant species in each. The inventoried plant species in the current work are frequently used for the treatment of various illnesses and to ensure the medication safety of Saudi people. The biological analysis of plant form used in Saudi natural remedies showed the dominance of herb and subshrub form with a percentage of 43% and 30% respectively. The most used preparation method of plant drugs, which used in Saudi Alternative medicine was decoction and infusion. The whole plant, leaves, seeds, and aerial parts were the most useful plant parts in natural preparation in Saudi traditional medicine with a percentage of 29%, 28%, 7%, and 5% respectively as reported in the present review work. The present review work gives big data about medicinal plants used in traditional medicine in the Kingdom of Saudi Arabia including data about plant species, used parts, preparation method as well as medical uses.  相似文献   
4.
刘国瑾 《生物学杂志》2011,28(3):112-113,91
新课程的实施需要运用探究教学法,广大高中生物教师对这一教法的运用还在摸索之中。通过拟从探究教学法的运用,对提高高中生物课堂教学有效性的作用,提出实践性的教学建议。  相似文献   
5.
为了更好地培养学生的能力,必须对传统的教学模式进行改革。针对传统教学模式下生物工程专业细胞生物学教学中学生积极性和主动性不强、缺少综合能力训练内容、作业抄袭、新知识与新进展反映不理想等问题,通过设定合理题目、规定格式和内容、单独报告、择优讲演等方式,利用学生的好胜心理、竞争性和成就感等,提出了新的教学模式。教学实践证明,新的教学模式能够充分调动学生学习的积极性和主动性,提高学生对专业知识的综合与归纳能力、表达演讲能力和电脑使用技能,同时也避免了作业抄袭现象的发生,强化了学生的自信心。另外,也对新模式中存在的问题进行了思考与建议。  相似文献   
6.
We used a quantitative ethnobotanical approach to analyze factors influencing the use value of plant species among men and women of the Rarámuri people in Cuiteco, Chihuahua, Mexico. We constructed a use value index (UV) combining the use frequency (U) and the quality perception (Q) of useful plant species by local people. We identified all plant species used by the Rarámuri and classified them into 14 general use categories. We interviewed 34 households in the village to compare men and women’s knowledge on the five main general use categories (and on their respective subcategories and specific uses), to document how they practice gathering activities and to calculate scores of plants UV. A total of 226 useful plant species were identified, but only 12% of them had high UV scores for the 42 specific uses defined. When the overall knowledge of plant species was examined, no significant differences were detected between men and women, but significant differences were identified in general use categories such as medicinal plants, plants for construction and domestic goods, but not in plants used as food and firewood. We identified a division of labor in gathering activities associated with gender, with women mainly gathering medicinal and edible plants and being involved in preparing medicines and food, whereas men were primarily gathering and using plants for manufacturing domestic goods, firewood, and building materials. Plant species UV associated to gender were significantly different between men and women at the level of specific uses in the general category of domestic goods and building. Frequency of use is highly associated with plant species quality perception.  相似文献   
7.
8.
《生物化学》是生物类专业的一门重要学科基础课程。《糖酵解》属于《糖代谢》一章的其中一节。本节内容的学习需应用前一章《生物氧化与氧化磷酸化》的已学知识,也是《糖代谢》后续内容《三羧酸循环》及《糖异生》等的学习基础,因此是本章教学的重要环节,教学效果的好坏将影响到《糖代谢》一章的整体教学质量。课程教学团队在多年课堂教学实践基础上,对《糖酵解》一节的课堂教学体会及思考进行了总结,供大家交流与参考。  相似文献   
9.
研究生细胞分子生物学教学探索   总被引:1,自引:0,他引:1  
为了培养具有科研思雏、德才兼备的研究生,在细胞分子生物学的教学中,从与人类生活及疾病相关的问题入手,以近年诺贝尔生理学或医学奖获奖相关工作为主线,要求学生阅读指定文献并自己查阅相关文献,采用启发式或讨论式等多种方式开展教学,让学生在学习过程中经历了文献查阅、综述撰写、会议报告的制作等过程,使学生掌握了基础理论,增强了发现问题的意识,培养了解决问题的能力,提高了学术交流的技能。从而使学生的道德修养和综合素质有了显著提高,为今后从事科学研究工作奠定了良好的基础。  相似文献   
10.
All physicians, at some point in their career, are responsible for the education of their peers and junior colleagues. Although medical students are expected to develop clinical and research skills in preparation for residency, it is becoming clear that a student should also be expected to develop abilities as a teacher. A handful of institutions have student-as-teacher programs to train medical students in education, but most students graduate from medical school without formal training in this area. When such a program does not exist, medical students can gain experience in education through participation in peer teaching, course design, educational committees, and medical education scholarship. In doing so, they attain important skills in the development, implementation, and evaluation of educational programs. These skills will serve them in their capacity as medical educators as they advance in their careers and gain increasing teaching responsibility as residents, fellows, and attending physicians.  相似文献   
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