山区微尺度环境探测参数拟合“瘴气”曲线

无线探测网络(wireless sensor network,WSN)可以方便采集复杂微环境物理参数,通过对多参数曲线拟合,形成描述微环境的拟合参数集与拟合参数曲线。研究通过具有单向对流通道的山地微环境的WSN多参数连续探测,揭示了微环境的微颗粒搬移过程。山区微环境不同空间存在的植被残屑、花粉等有害粉末与山地团雾混合后,通过对流与山风等微环境气象形成的物质搬迁。当搬迁物质在低地空间产生物质沉积,成为山区瘴气等灾害动因。实验通过沿通道部署多参数WSN,通过对团雾的识别与颗粒密度(搬迁物质)峰值曲线拟合,证实了这种上团雾的迁移规律,部分证实了历史上瘴气存在与影响。     

治疗输入性疟疾30例临床特征分析

目的了解输入性疟疾的临床特点、抗疟药治疗效果,为临床诊治提供参考依据.方法对收治的30例非洲务工疟疾患者的临床表现、实验室检查、治疗方案进行回顾性分析.结果血检疟原虫阳性19例,其中,恶性疟原虫6例,间日疟原虫5例,分型不详8例;30例中单用蒿甲醚治疗10例,青蒿琥酯治疗8例,双氢青蒿素哌喹片治疗5例,氯喹治疗1例,蒿甲醚联合双氢青蒿素哌喹片治疗6例;疗程最短2 d,最长15 d,所有病例最终均有效控制症状.结论输入性疟疾临床症状典型,有急性肝损害、急性血管内溶血、急性肾衰竭、脑型疟疾及肺病变等常见并发症,血检疟原虫阳性率较高,常用抗疟药物能有效控制症状.     

Malarial parasites complete sporogony in axenic mosquitoes

Summary To obtain sporogonic stages of malaria free from microbial contaminants for in vitro studies,Anopheles stephensi were reared under sterile conditions using a mosquito cell line as larval food. The adult females, kept in sterile humidified containers and allowed to engorge on parasitemic hamsters, supported the sporogonic development of the rodent malarial parasitePlasmodium berghei. In 10 experiments, the proportion of infected mosquitoes varied from 0 to 92%, and the geometric mean number of oocysts per female mosquito from 2.5 to 58,6, with a range of 1 to 548. The average number of salivary gland sporozoites per infected mosquito was determined by direct sporozoite counts in the pooled homogenate of the thoraces of all female mosquitoes. In five experiments, it varied from 2.7×10³ to 9.0×10³. The sterile sporozoites, harvested on day 19 or 20 after the infective blood meal, were as infective for rodents as nonsterile ones.Supported in part by Public Health Service research grant AI 18345 from the National Institute of Allergy and Infectious Diseases, by a grant from the Agency of International Development DSPE-5542-G-SS-3042-00, and by a Charles and Johanna Busch award.     

非线性最小二乘法分析疟疾发病率的变化趋势

应用非线性的最小二乘法的L-M算法分析全国流行性疟疾发病率随时间变化规律.结果发现:疟疾发病率呈现出大幅度的周期性变化和长期的缓慢增加.由于标准偏差较小,线性迭加二阶的傅里叶多项式可能代表疟疾发病率的真实变化规律.疟疾发病率周期性变化的周期约为1年,这与长期监测的结果相一致;而1%左右的增加率可能是由于近几年人口流动激增和严重的环境污染造成的。     

Some trends in medical populations genetics

Summary Five topics concerning medical population genetics have been selected for discussion: in the field of population cytogenetics, the frequency of chromosomal aberrations and the roles of mutation and selection in the maintenance of balanced rearrangements are studied; the long term genetic effects of treatment and prevention of genetic diseases are reviewed; the relationships between malaria and the sickle-cell trait are discussed; some recent works concerning human DNA polymorphisms in the field of population, genetics are presented, and finally, some methods of genetic epidemiology are described.     

Malaria prophylaxis in travellers: The current position

Summary Malaria prevention is a main challenge for physicians, nurses, health officers and tour operators. The attack rate of malaria in travellers is 1–10/10,000 departures, and the case fatality rate of imported malaria is around 0.5/100. Travellers should be informed about the risk they are going to take, how to protect against mosquito bites, about the antimalarials they will have to take and about what to do when a malaria breakthrough should occur.The 4-aminoquinolines (chloroquine, amodiaquine) remain the drug of choice for the prevention ofPlasmodium vivax and of sensitiveP. falciparum infections. The problem is to find an effective and safe drug combination for travellers to areas whereP. falciparum is either resistant to chloroquine, to Fansidar (the combination of pyrimethamine plus sulfadoxine) or to both. These travellers will probably best be protected by an individually tailored drug combination, which includes amodiaquine or mefloquine as baseline drugs, and a supplementation with Fansidar, Maloprim (the combination of pyrimethamine with dapsone), paludrine or an antibiotic.     

Pathogenesis of Plasmodium falciparum malaria: the roles of parasite adhesion and antigenic variation

Malaria results in up to 2.5 million deaths annually, with young children and pregnant women at greatest risk. The great majority of severe disease is caused by Plasmodium falciparum. A characteristic feature of infection with P. falciparum is the accumulation or sequestration of parasite-infected red blood cells (RBCs) in various organs, such as the brain, lung and placenta, and together with other factors is important in the pathogenesis of severe forms of malaria. Sequestration results from adhesive interactions between parasite-derived proteins expressed on the surface of infected RBCs and a number of host molecules on the surface of endothelial cells, placental cells and uninfected RBCs. Some receptors for parasite adhesion have been implicated in particular malaria syndromes, such as intercellular adhesion molecule 1 in cerebral malaria and chondroitin sulfate A and hyaluronic acid in placental infection. The principal parasite ligand and antigen on the RBC surface, P. falciparum erythrocyte membrane protein 1 encoded by a multigene family termed var, is clonally variant, enabling evasion of specific immune responses. An understanding of these host-parasite interactions in the context of clinical disease and immunity may reveal potential targets to prevent or treat severe forms of malaria. Received 25 June 2001; received after revision 22 August 2001; accepted 24 August 2001     

青蒿素类药物专利技术分布研究

青蒿素是中国科学家自主创新的倍半萜内酯类抗疟化合物。经几十年的发展，该类药物已经成为
治疗疟疾的首选药物。然而，在巨大的国际市场中，中国企业却基本处于产业链的底端。该文力图从专利保
护的角度分析中国青蒿素产业缺乏市场竞争力的原因，并提出解决问题的建议。     

疟疾子孢子疫苗的研究进展

本文系统地回顾了疟疾疫苗的发展史，将疫苗研究的发展分为与生物技术的发展密切相关的三个时期；重点阐述了疟疾子孢子疫苗在不同时期的研究进展，并分析了疟疾疫苗研究的现状和面临的困难。     

一类疟疾传播模型的稳定性和后向分支

建立了一类关于疟疾传播的SIS-SI模型.首先通过分析模型的无病平衡点的局部渐近稳定性,得到了模型的基本再生数公式;然后证明了当基本再生数大于1时,模型存在唯一的地方病平衡点;当基本再生数小于1时,模型可能存在两个地方病平衡点,这表明模型会存在后向分支.证明了后向分支的存在性.讨论了无病平衡点的全局稳定性;最后对所得理论结果进行了数值模拟.