碱裂解法小量制备质粒DNA应注意的问题

质粒DNA的小量制备是基因克隆中的常规操作 ,可快速提取质粒DNA进行各种鉴定或进一步操作 ,本文就碱裂解法谈一下质粒DNA提取操作中应注意的问题。1)无菌条件下挑取琼脂培养板上的单菌落 ,移至 2～ 5ml,含适当抗生素的LB培养液中 ,37℃培养 8～ 10h为最适。2 )取 1 5ml培养液至离心管 12 0 0 0r/min离心 30s,离心机启动时间不应计算在此 30s内。3)弃上清 ,要使菌体和管壁上不残留液体 ,旨在去除细菌生长过程中代谢废物和脱落的细胞壁 ,否则会影响质粒的质量和内切酶酶切效果。4 )溶液Ⅰ、Ⅲ在使用前要预冷。5 )溶液Ⅱ现用现配 ,加溶液…     

关于建立独立企业纳税会计的探讨

纳税会计作为财务会计组成部分的核算模式，使增值税进项税额抵扣，递延流转税、递延所得税等涉税业务的核算存在弊端。解决上述弊端的有效途径是建立独立企业纳税会计，分析了我国建立独立企业纳税会计的可行性：会计电算化的发展为其提供了有效途径；会计制度的改革为其提供了前提条件：税收征管体制的改革为其提供了实施依据．在我国建立独立企业纳税会计的初步构想是：企业纳税会计与财务会计相分离而自成体系．设置系统的独立纳税会计科目和完整的账簿组织体系。根据涉税业务进行相关账务处理。     

The vexing problems of vaccine compensation

Debate continues in the United States over the best way to compensate children who are injured by vaccines administered as part of the public health campaign against childhood diseases. Blaming increased liability costs, several drug companies have stopped production of essential vaccines, raising fears of shortages. Proposals that the federal government sponsor a compensation system have met with approval from parents of injured children, medical associations, and drug companies, although these groups disagree over whether victims should retain the right to sue the vaccine manufacturers as an alternative to receiving federal compensation. Legislation has been introduced in both houses of Congress to establish a compensation program, but Administration opposition is expected to the potential expense and the broad range of coverage.     

浅议新形势下解决乡村债务的途径和措施

乡村债务问题是目前社会各界都非常关注的问题。在新形势下,尤其是在新农村建设中,解决好这一问题意义更加重大。然而,要真正解决好这一问题,除了要有好的思路外,还必须采取正确的方式和有效的措施。本文将围绕这些方面谈一些自己的看法。