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81.
82.
生物化学实验室教学改革与建设问题的探讨   总被引:1,自引:0,他引:1  
随着科学技术的不断发展,生物化学技术发展日新月异。结合玉林师范学院的实际情况,通过实际教学工作,针对生物化学实验室完善教学制度、更新硬件设施、增加实验室的投资、加强实验室维护和降低成本损耗、管理实验室的经费等建设方面的问题进行了思考和探索,提出了一些具体的解决策略,并对实验室的建设和发展前景进行了展望。  相似文献   
83.
义乌游泳馆采用凹形屋盖,对这种屋盖结构的风荷载研究还比较少.为此,制作了比例为1:100的刚性模型,采用同步测压技术,进行了义乌游泳馆凹形屋盖的风压测量,得到了其屋盖上的平均风压系数分布并与凸形屋盖的试验结果进行比较.结果表明:凹形屋盖上的“吸力”要远大于凸形屋盖上的“吸力”;迎风向挑棚上、下表面压力出现不利的负相关,应引起设计人员的注意;周边建筑对义乌游泳馆屋盖风荷载的影响不大.最后还给出了义乌游泳馆屋盖上的前10个最小极值风压.  相似文献   
84.
凌育赵 《安徽农业科学》2009,35(19):9279-9281
介绍了模拟化学实验室在绿色化学教育中的重要性,分析了模拟化学实验的优势与作用。  相似文献   
85.
我国《教育信息化十年发展规划(2011-2020年)》提出“推进信息技术与高等教育的深度融合”,目前部分高校已开始采用慕课形式开展实验室安全及规范操作教育。在分析慕课优势以及当前高校实验室安全及规范操作慕课建设不足的基础上,提出了慕课建设应以教师结合学生的需求为核心,并对课程的内容和评价体系给出了思路。  相似文献   
86.
• Developed a two-step synthetic route to anti-plant-virus candidate NK0238. • NK0238 exhibited a broad antivirus spectrum in greenhouse. • NK0238 showed comparable antivirus activities as controls in field trials. • NK0238 was safe to birds, fish, bees and silkworms. • NK0238 has a very good prospect in commercial development. It has previously been shown that tryptophan, the biosynthesis precursor of Peganum harmala alkaloids, and its derivatives have anti-TMV activity both in vitro and in vivo. Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of l-tryptophan with triphosgene to produce l-tryptophan-N-carboxylic anhydride, which then reacts with n-octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a>40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.  相似文献   
87.
88.
The surgical success of laparoscopic castration without orchidectomy results from avascular necrosis of the testes. However, failures and subsequent production of testosterone and stallion‐like behaviour have been previously identified. Laparoscopic castration without removal of the testes was performed in 32 horses with 2 normal descended scrotal testes between July 2006 and October 2012. The objectives of our study were to evaluate the success rate of laparoscopic castration without orchidectomy on descended testes in our population and assess complications and recovery time. Endocrine tests were performed after surgery and owners also asked to report on their horse's behaviour and ability to resume exercise. Castration was deemed successful if endocrine test results were in accordance with gelding values. Failed horses were castrated using a conventional technique and histology performed when possible. Basal testosterone levels decreased below 3 nmol/l after surgery in 30/32 cases. However, in 2 horses, stallion behaviour persisted and histological evaluation after inguinal castration showed residual viable tissue. Two horses maintained high testosterone levels after surgery associated with stallion‐like behaviour. Based on these results, 12.5% of horses (4/32 horses) failed to be considered a gelding based on either endocrine tests and/or histology. All horses, with one exception, were able to resume exercise less than a week after the procedure. Laparoscopic castration without orchidectomy appears to be a safe procedure. When assessing the success of laparoscopic castration, our total failure rate was 12.5% (4/32 horses) which is significantly higher than previously reported.  相似文献   
89.
Two infection protocols, individual oral (IO) and waterborne infection (WB), were evaluated to challenge Penaeus (Litopenaeus) vannamei with White Spot Syndrome Virus (WSSV). Five different batches of full and half-sib families were infected experimentally and tested for growth performance under commercial growth conditions. The genetic variance for WSSV resistance was estimated using a linear sire-dam repeatability model that considers test-day survival as the dependent variable. The heritability estimates using the IO protocol ranged from 0.01 ± 0.00 to 0.02 ± 0.01, whereas the heritability estimates using the WB infection protocol were not significantly different from zero. The genetic correlations measured as the product moment correlation between full-sib family breeding values for resistance to WSSV and harvest body weight in ponds were unfavourable in three of the five batches and favourable in one of them. The dosage of WSSV was better controlled with IO oral infection than with other methods, with all animals being exposed to approximately the same risk of infection at the same time. This should improve the accuracy of the genetic parameters and hence improve the accuracy of the breeding values. It should, however, be noted that once the outbreak was established and the mortalities began, the shape and the magnitude of the slope of the mortality curves showed little difference in the infection pattern between batches irrespective of the dosage and infection protocol, and in most of the cases the cumulative mortality was greater than 80%. The main reason for this is probably the high densities of animals in the tanks needed for the genetic evaluations.  相似文献   
90.
为探讨河南省部分地区鸭肝炎病免疫失败的原因,对分离到的鸭肝炎野毒株(LY株)在雏鸭、鸭胚及鸡胚上进行免疫保护试验、交叉中和试验。结果表明DH-Ⅰ型血清对该LY株的免疫保护指数较低,明显低于LY株血清的保护指数,表明该疫区部分鸭肝炎野毒株的抗原性已发生改变;交叉中和试验对该结果进行了进一步的验证;另采用LY株和DHV-I病毒疫苗联合制备鸭肝炎高免蛋黄抗体用于临床免疫防治可使临床保护率达到90%以上。  相似文献   
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