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为了探讨WPBL教学法在"微生物学检验"教学中的应用效果,对本院2008级检验医学专业66名学生进行分组教学,实验组采用WPBL教学法,对照组采用传统教学法。课后对2组学生进行理论测试,同时对实验组进行问卷调查。经统计,实验组的测试成绩明显优于对照组(P0.01),且2组学生测试成绩的及格率差异有统计学意义(P0.05);问卷调查显示90%以上的学生对WPBL教学法感兴趣,认为WPBL教学法能提高学习兴趣、自学能力和分析解决问题的能力。从结果看,WPBL教学法能够提高"微生物学检验"教学质量。 相似文献
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Jaqueline Inês Alves de Andrade Eduardo Akifumi Ono Glauber Cruz de Menezes Elenice Martins Brasil Rodrigo Roubach Elisabeth Criscuolo Urbinati Marcos Tavares-Dias Jaydione Luiz Marcon Elizabeth Gusmo Affonso 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):576
This study evaluated the influence of diets supplemented with 500, 800, 1200 mg kg− 1 of vitamin C (ascorbic acid or AA) and vitamin E (α-tocopherol or α-T) on the physiological responses of pirarucu fed for 2 months. Weight and mortality were not affected by dietary vitamin type or their concentrations. Significant increase (p < 0.05) on the red blood cells count was obtained on treatments with 800 and 1200 mg AA kg− 1 and on the hemoglobin concentration on treatment with 500 mg α-T kg− 1 relatively to control. Mean corpuscular volume presented a significant decrease (p < 0.05) on treatment with 800 and 1200 mg AA kg−1 when compared to control. Mean corpuscular hemoglobin concentration was significantly high (p < 0.05) on treatment with 500 mg α-T kg− 1. Only in vitamin C treatments, we noticed a significant increase (p < 0.05) in the number of leucocytes relative to control. All fish in the vitamin-supplemented treatments, except 500 mg AA kg− 1, had high total protein values compared to control. Fish treated with 800 or 1200 mg α-T kg− 1 also showed increases in plasma glucose concentrations. Our results suggest that 800 and 1200 mg AA kg− 1 are probably the most suitable concentrations for pirarucu diets, although high vitamin E diets are not necessary for quantitative leucocyte increases for this species. 相似文献
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Nitric oxide (NO) is a short lived diatomic free radical species synthesized by nitric oxide synthases (NOS). The physiological
roles of NO depend on its local concentrations as well as availability and the nature of downstream target molecules. At low
nanomolar concentrations, activation of soluble guanylyl cyclase (sGC) is the major event initiated by NO. The resulting elevation
in the intracellular cyclic GMP (cGMP) levels serves as signals for regulating diverse cellular and physiological processes.
The participation of NO and cGMP in diverse physiological processes is made possible through cell type specific spatio-temporal
regulation of NO and cGMP synthesis and signal diversity downstream of cGMP achieved through specific target selection. Thus
cyclic GMP directly regulates the activities of its downstream effectors such as Protein Kinase G (PKG), Cyclic Nucleotide
Gated channels (CNG) and Cyclic nucleotide phosphodiesterases, which in turn regulate the activities of a number of proteins
that are involved in regulating diverse cellular and physiological processes. Localization and activity of the NO-cGMP signaling
pathway components are regulated by G-protein coupled receptors, receptor and non receptor tyrosine kinases, phosphatases
and other signaling molecules. NO also serves as a powerful paracrine factor. At micromolar concentrations, NO reacts with
superoxide anion to form reactive peroxinitrite, thereby leading to the oxidation of important cellular proteins. Extensive
research efforts over the past two decades have shown that NO is an important modulator of axon outgrowth and guidance, synaptic
plasticity, neural precursor proliferation as well as neuronal survival. Excessive NO production as that evoked by inflammatory
signals has been identified as one of the major causative reasons for the pathogenesis of a number of neurodegenerative diseases
such as ALS, Alzheimers and Parkinson diseases. Regenerative therapies involving transplantation of embryonic stem cells (ES
cells) and ES cell derived lineage committed neural precursor cells have recently shown promising results in animal models
of Parkinson disease (PD). Recent studies from our laboratory have shown that a functional NO-cGMP signaling system is operative
early during the differentiation of embryonic stem cells. The cell type specific, spatio-temporally regulated NO-cGMP signaling
pathways are well suited for inductive signals to use them for important cell fate decision making and lineage commitment
processes. We believe that manipulating the NO-cGMP signaling system will be an important tool for large scale generation
of lineage committed precursor cells to be used for regenerative therapies.
Special issue dedicated to John P. Blass. 相似文献
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留学生教育作为高等院校国际化程度的一个重要尺度,已经成为高等教育的重要任务之一。留学生教育质量的高低在留学生教育事业上有着举足轻重的地位。我们体会到,通过采取以下措施,可以提高留学生教学质量:加强师资队伍建设,提高授课教师专业素质;多种教学模式,提高学生学习兴趣;加强师生交流,提高学习热情。 相似文献