Malaria parasites--discovery of the early liver form

Infections of mammalian malaria parasites start when sporozoites from an infected anopheline mosquito are injected into the bloodstream of the host. The sporozoites enter the hepatocytes and become transformed into exoerythrocytic schizonts. Since the discovery of the primate parasite Plasmodium cynomolgi in monkey hepatocytes and the rodent parasite Plasmodium berghei in hamster hepatocytes, the ultrastructure of these stages has been extensively studied both in primate and rodent plasmodia. These observations relate only to the development of the exoerythrocytic schizont 25 h after sporozoite injection until the final maturation (of P. berghei) 50 h post-inoculation. Recently, we have studied the route of entry of sporozoites across the cellular lining of liver sinusoids and invasion of the liver parenchymal cells by using transmission electron microscopy. The results of these studies in combination with other physiological experiments strongly suggested that the sporozoite was initially harboured by the Kupffer cell, from which the parasite escaped into the neighbouring hepatocyte. The migration of sporozoites from liver sinusoids to hepatocytes can be achieved within a few minutes. We present here the first ultrastructural observations on the natural transformation of intrahepatocytic sporozoites into exoerythrocytic forms in vivo, using the rodent malaria parasite P. berghei in a laboratory host, the Brown Norway rat. These observations complete the search for the final link in the life cycle of malaria parasites.     

国家纺织标准与ISO标准接轨的探讨

本文就我国纺织产品的标准与国际ISO标准进行了比较与分析．提出了我国纺织产品标准与国际ISO标准接轨的可行性措施。     

浅析1943年喜饶嘉措进藏受阻事件

1942年,正在抗日战争的关键时期,西藏发生所谓“外交局”事件,意欲造成中央与西藏地方政治关系对等的假相,以期实现最终分裂国土的企图。消息一出,全国上下反对之声不绝。国民政府发出最后通告,并陈兵于康藏、青藏交界。这时中央与西藏地方政府的关系陷入困境之中,在此紧要关头,拉然巴格西喜饶嘉措受命于1943年前往西藏,主要是希望借助其声望及地位开展爱国活动。喜饶嘉措一行在黑河(今那曲)受阻,被迫内返。关于这一事件由于缺乏原始资料,故一直没有详细的记载。2005年台湾蒙藏委员会发行的《蒙藏委员会驻藏办事处档案汇编(1-6)》中有部分原始档案正可弥补这一缺失。     

九十年代科学技术进入主战场的几点思考

本文就开发、研制新产品为龙头,较深入地探讨了九十年代我国科学技术如何进入主战场?进入主战场应以选好主攻方向和相应的战略重点为突破口;以全球科技信息开发、研制新产品重要技术依据。并结合我国当前教育界、科技界存在的问题。强调教育的战略重点,育人的重要机制;最后,就目前我国当政的各级政府应该履行、从事的几项工作及做好工作的几点建议。