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1.
银杏化学成分及药理作用的研究和应用进展 总被引：7，自引：0，他引：7
银杏（Gimkgo biloba）又名白果树，为银杏科，银杏属植物。银杏具有多种化学成分、毒性成分和有效成分，银杏中有效成分的药理作用促进了银杏有效成分分离提取技术的研究。我国银杏制剂研究开发在经历了一哄而上的局面后已逐步走向成熟和规范。 相似文献
2.
黄晓梅 《十堰职业技术学院学报》2007,20(5):89-91
分析5种高毒农药的发展的基本情况以及高毒农药禁用的必要性与可行性,及其禁用高毒农药应采取的对策。最后提出了相关的结论与建议。 相似文献
3.
近年来冰毒的市场在不断扩大,冰毒的制备方法也在不断发展和变化,α-溴代苯丙酮已经成为了制备冰毒新的原料。本文简要介绍了α-溴代苯丙酮的理化性质、生产和应用情况;研究了α-溴代苯丙酮的鉴别方法、制备麻黄素的方法;提出了α-溴代苯丙酮的管制建议,以期为更好的监管α-溴代苯丙酮提供重要基础。 相似文献
4.
硼及其化合物在动物营养方面的研究进展 总被引：2，自引：0，他引：2
生理量硼对动物具有营养作用,高剂量硼则有不利影响,甚至具有毒性作用。本文从动物对硼的吸收和排泄,硼在动物机体内的分布,硼与钙、镁、磷等微量元素代谢的关系,硼对骨代谢、生长性能、能量底物代谢、血细胞、血液生化指标、免疫功能、生殖细胞、胚胎发育和神经内分泌功能的影响,以及硼的毒性作用等方面论述了硼对动物的营养和毒性作用,并对有待研究的问题进行了探讨。 相似文献
5.
阐述了水体中一些微量毒性元素，如Pb, Hg, Cd, Cr, Se, Tl, As, Be, Al等的水化学特性，分析了它们的环境地球化学特征，并对自然水体中毒性微量污染物的来龙去脉以及对人体的可能危害性进行了初步的探讨。 相似文献
6.
目的:观测小鼠依次口服大剂量曼陀罗、闹羊花、马钱子、斑蝥等10种广西产有毒中药的半数致死量,以评价其安全性。方法:每种中药在死亡率0%(Dn)和100%(Dm)范围内确定5～7个给药剂量,每个剂量组用20只小鼠进行观察7天,用Bliss法计算出半数致死量(LD50)等数据。结果:从半数致死量看,半夏的毒性在所有10种受试中药中最低;斑蝥毒性最高。毒性大小顺序为:斑蝥>蟾酥>马钱子>曼陀罗>闹羊花>木鳖子>山豆根>蛇床子>木通>半夏。结论:①多数受试有毒中药与药典标注的毒性程度基本相符;②根据不同毒性中药的半数致死量,可为中毒案件的侦破和定论提供科学的依据。 相似文献
7.
本文研究了不同浓度Hg2+对苦草O2.-、MDA含量和抗氧化酶系统的影响。实验结果表明:随着Hg2+浓度的增加,对苦草的毒性效应呈现加重趋势,具体表现为O2.-和MDA含量先升后降,MDA峰值较O2.-滞后,SOD、POD活性先升后降,体现植物具有一定的抗性机制;CAT活性持续下降,在清除活性氧自由基过程中作用不明显。 相似文献
8.
John Smyth 《Educational Philosophy and Theory》2020,52(7):716-725
AbstractThis article deploys critical sociology to examine institutions of higher learning, worldwide, within a context of a more utopian set of possibilities. The article contests the idea of universities as marketplaces – competition, commercialisation and vocationalisation; the synthetic values of docility, conformity, and image/impression management; the calibration and metrification of all facets of university activity; and the containment of universities as places of dissent and social critique, shackling them instead to the whims of capitalism. As an alternative, the author explores Klein's elements of a social imaginary that involves extirpating the alien interloper neoliberal ideology that has been allowed to invade and colonise universities, and instead allowing indigenous ideologies to emerge from the discourses of those who do academic work. The austerity logic that has so poisoned universities, is replaced by the humanising and democratising practices and voices of those who have been wilfully excluded. Above all, what the author pitches towards is not ‘fixing’ our broken universities, for that would be in Klein's terms ‘fitting into the box’ that has been constructed for universities over the past half-century, but rather an ‘exploding of the box’. Examples from the author's prior community-based research are used to illustrate humanising, transformative possibilities. 相似文献
9.
本文介绍了含游离甲醛低、黏结强度大的建筑行业用脲醛树脂黏合剂的制备方法 .研究了树脂合成过程中原材料纯度、尿素和甲醛的摩尔比、反应温度以及反应时间等对黏度和固含量等性能的影响 .在一定酸度和温度条件下 ,分批加入尿素进行阶段反应 ,得到一种胶液性能稳定、黏结强度高的建筑板材用黏合剂 . 相似文献
10.
Herman Sunil D'Souza Geraldine Menezes T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2003,18(2):154-160
Heavy metals are important toxicants known to exert adverse effects in humans and animals, given sufficient exposure and accumulation
in the body. This has a great concern both at personal and public health risk. Heavy metals are also known to interact with
the essential trace minerals at the level of absorption and also during the metabolism. The adverse effects of the absorbed
and accumulated heavy metals include neurological, reproductive, renal and hematological systems. Children are more sensitive
than adults to the effects of lead. Efforts are made to understand the mechanism of the interactions of heavy metals with
essential trace minerals at the level of absorption. With available sensitive and specific methodologies like Anodic Stripping
Voltammetry for the evaluation of the levels of toxic heavy metals such as lead, cadmium, mercury etc., better understanding
of heavy metal absorption is made possible.
Due to the poor nutritional standards, risk of heavy metal exposure is still a major concern in developing countries. Studies
carried out by the author have provided evidence towards the understanding of the prevailing mechanisms of metal-metal interaction
at the intestinal level. During growth and development the demand for the essential minerals being at higher level, differentiation
of various essential metals and heavy metals pose an inherent problem due to certain common properties shared by them. With
this approach to the problem of heavy metal toxicity, it is preventable not only with environmental intervention but also
by the nutritional management. 相似文献