Mesoglia & microglia--a historical review of the concept of mononuclear phagocytes within the central nervous system

More than a century and a half has elapsed since the first accounts of mesodermal phagocytic elements were proposed within the central nervous system. Over the intervening decades, body and substance were added to this concept through the advancement of histological techniques at the disposal of the researcher and the acute and keen-minded skills of the pathologist. Notable among these pioneering efforts were the contributions of W. Ford Robertson, Santiago Ramon y Cajal, Pio del Rio-Hortega and Wilder Penfield amongst an entire cavalcade of other noteworthy figures. The term 'mesoglia' and 'third element of the nervous system' was bestowed upon these cells towards the beginning of the twentieth century to account for their separate origins from neurons and macroglia. It was later amended by del Rio-Hortega in 1919, to 'microglia' in order to further discriminate between true mesodermal elements and oligodendrocytes, previously regarded as a component of 'mesoglia'. This particular contention sparked much controversy among del Rio-Hortega's peers and resulted in an escalation of fruitful research throughout Europe that eventually declined up to the outbreak of the Second World War. The post-war years were a period of the 'dark ages' that cast doubt on the very existence and nature of microglia, until the 'renaissance' of research was once again rejuvenated in the 1960s, by a new cohort of intrigued minds: Cammermeyer, Blinzinger, Kreutzberg and others who saw in the 'third element' the potential that is now commonly ascribed to microglia: the intrinsic immune effector cells of the CNS. It is now universally accepted that microglia are involved as the first line of rapid defence in any pathology of the nervous system, and as such, present a diagnostic tool for the neuropathologist. Although our knowledge of microglia stems from an extensive body of work conducted over the last two decades, much of the earlier work (pre-1960s) has remained somewhat obscure. This is partly accountable due to the limited availability of translated works, and additionally to the lack of a compendium of these articles. This paper will present a comprehensive overview of the pioneering research on mononuclear phagocytes within the central nervous system, which has direct bearing on our present-day understanding of the concept of microglia.     

中国早期人造蓝色颜料──硅酸铜钡

鉴定出在中国汉代（208Bc－220AD彩陶器上的一种人工生产的矿物──硅酸铜钡（BaCuSi_4O_(10)）,并观察到这个矿物是属于我国战国（475-221BC）或汉代的八面棒的一个主要成分。这个人造矿物迄今还未作为古代中国颜料被报道过。     

《作为人类生态学的考古学》(节译)

第一章考古学的综合性引言考古学现在正处在十字路口上。从六十年代晚期到七十年代早期,在北美考古学的中心舞台上,人们不再是争相解释历史过程而是在讨论新考古学。这是一场公开的论战,其起因在相当程度上是由于在1960年以前的三十多年里考古学的实际资料指数地增加,但资料收集的增多并不能等同于真实知识的增长,资料的综合只是呈现为描述性的、简单化的和推测性的趋势。新考古学作为美国两代人之间冲突的产物,作为对考古学方     

新加坡的地理学

在新加坡,地理学高等教育一直在拉费尔斯学院进行,这所学院是由英国殖民政府在1928年建立的.从1949年开始,随着马来亚大学的成立才设置了地理学学位课程.地理学第一任主席由E.H.G.多比担任.1959年,一些地理教师转到了新成立的吉隆坡的马来亚大学.随着政治上的变化,新加坡马来亚大学从吉隆坡大学中分离出去,并在1962年成为新加坡大学.1980年这所新加坡大学与一所1953年成立的私立华人学校合并成国立新加坡大学,并在肯特山建立了新的校园.从这时候起,新加坡一直只有一个负责地理学高等教育的地理系.     

脆弱铁器的清洗

易碎的铁制品或表面带有涂料和有机化合物的铁器,采用化学还原剂如碱性亚硫酸盐或胺类等处理是不行的,需要做脱盐处理,即使氯离子的含量不能完全去除,这也是必要的.而铁器的脱盐清洗通常是水洗的过程,最好是要在情性的气氛或无氧化作用的条件下进行.采用索格利特萃取器（以下简称索氏萃取器）通氮的方法排除氧气,并用蒸馏水有效地去除氯离子.目前保护铁器中还未广泛地使用这一方法,本文主要介绍这一方法,以求引起注意.清洗过程是自动的,可同时处理好几件小型的铁器.要处理的铁器的尺寸大小取决于索氏萃取器自身的容积. 】     

From temporary to permanent townsmen: migrants from the Malalaua District,Papua New Guinea

An attempt is made to explain how a group of people moved from being newcomers to town in the 1940s to being one of the most permanent and stable residential elements in Papua New Guinea's towns in the 1970s. Circular and permanent migration, as Young maintains, are not 2 distinct processes, and both initial rural urban movements and migrants' decisions to return or not to return home are examined simultaneously. The hypothetical career of a migrant is considered all the way from village residence to permanent urban residence along with the different decision points that might vary this career. In this case study focus is on 2 sets of factors that affect migration decisions: an imbalance in rural and urban economic conditions and the effects of the migration process itself. The people discussed come from what is now known as the Malalaua District of the Gulf Province and are referred to as Malalauas. Historically, there are several feastures of Malalaua urban migration that are important. Malalaua migration began earlier than that of most urban migrant groups in Papua New Guinea. In the 1963 urban population there were a number of Malalauas who first came to Port Moresby before or during World War 2. Migration from the Malalaua District has continued in a steady stream from the 1940s to the 1970s, although there is no evidence on absolute numbers of new migrants in any 1 year. The pattern of Malalaua migration to towns over the entire period has been largely one of the movement of young single adult males and young female adults moving to town on marriage. Both the absolute numbers of migrants and the proportion of Malalauas absent from the District have risen rapidly over the 20 years to 1972. Finally, children are being born to Malalaua migrants in town. Malalauas are possibly the migrant group most firmly established in town. The Malalauas are one of the most longterm and residential groups in Port Moresby. In Papua New Guinea as a whole they must be one of the migrant groups with the greatest commitment to urban living. Economic factors have been very important in Malalau decisions to leave the village, particularly the decisions of adult males. The migration process itself has increasingly affected migrant decisions: factors such as the diminished attraction of a depopulated rural community, a change in tastes towards urban based ways of living, the growth of strong personal and family ties among urban residents, and a simultaneous reduction in such ties with rural residents. It is argued that this 2nd set of factors over time increases in importance relative to rural-urban economic imbalance as an explanation of migration behavior. In general, rural urban economic opportunities have become less important over time. So in the 1970s and 1980s it would be argued that many Malalauas would not respond to increases in urban unemployment of rural incomes by moving back to the village. They would be permanent townspeople. This explanation of migration decisions is dynamic: in the history of individuals and groups the context and thus the explanation of decisions change.