中国肿瘤防治工作进入新时期

 肿瘤在历史长河中一直是比较罕见的疾病,但到20世纪30年代,首先在发达国家,随后在发展中国家,肿瘤开始步入常见病之列。近50多年来,中国肿瘤的发病率不断缓慢攀升,因癌症导致的死亡在所有居民死亡原因中已经占首位,而且已经超过全球平均水平,肿瘤防治成为中国面临的一项严峻任务。本文从中国肿瘤现状出发,综述肿瘤高发区研究、抗肿瘤新药研究、临床肿瘤学科发展、精准医学等方面的进展,并提出中国肿瘤防治工作的建议。     

一种新的杀线虫担子菌

YL14是一种首次发现具杀线虫活性的担子菌,12h内对松材线虫（Bursaphelenchus xylophilus)的致病率达90％以上,是一株有应用前景的线虫生防菌。本试验观察了该菌对线虫的致病过程,证明其杀线虫机制是产生杀线虫毒素。经液体发酵,活性组分存在于发酵液中,不需线虫诱导能稳定生成,为水溶性,对热不敏感。     

Culture of a new medicinal leech: growth,survival and reproduction of Hirudo orientalis Utevsky and Trontelj, 2005 under laboratory conditions

The increasing demands for medicinal leeches around the world has increased the need for new sources of leeches. To assess the feasibility of culturing a new medicinal leech species, growth, survival and reproduction of Hirudo orientalis was investigated under laboratory conditions (28°C; 9.5D:14.5L light regime; monthly feeding by sheep blood) from hatching until sexual maturity. Several interesting results emerged from this study. (1) The first copulation was observed in 5.5-month-old leeches and cocoon deposition started by six months. (2) Cocoon length and diameter did not differ significantly between six- and nine-month-old leeches, but the percentage of leeches depositing cocoons was significantly higher in the nine-month old group. (3) The growth curve was saltatory, similar to other sanguivorous species. The mean (±SE) wet weight of 6-month-old individuals was 4.70 (±0.86) g. (4) Weight gain rate decreased with increasing age. (5) Mortality only occurred in the one-, seven- and eight-month age groups at the rate of 5.7%, 23.1% and 14.3%, respectively.     

不同低温条件下吉富罗非鱼的耐受性研究

应用室内人工降温,以0.5 ℃/2 h的降温方法研究吉富罗非鱼的低温耐受能力,分析比较不同低温条件下吉富罗非鱼的昏迷情况和死亡情况,评价其低温耐受性.结果表明:在8、9、10和11 ℃持续低温胁迫下,吉富罗非鱼的昏迷温度在8.9～10.5℃,半数昏迷温度为9.6℃左右;从开始出现昏迷到全部死亡的经历时间分别为14.5、18.5、24.5和28.5 h;昏迷维持时间与累计死亡率呈显著的线性相关,分别为:y=-0.0489x2+1.4330x-9.5078(R2=0.9999)、y=-0.0136x2+0.5024x-3.6385(R2=0.9649)、y=0.0038x2-0.0461x-0.1344(R2=0.9843)和y=-0.0034x2+0.2443x-3.2131(R2=0.9945).吉富罗非鱼的耐受性与时间和温度密切相关,其中8℃组耐受时间最短,11℃组最长.     

基于数据差异的Lee-Carter模型的估计与应用

Lee-Carter模型是死亡率预测中最常用的模型,鉴于我国人口死亡率数据的来源差异,在Lee-Carter模型的参数估计中纳入数据质量因子,对不同数据质量的数据分配不同的权重,然后利用极大似然法得到各参数的估计值.在此基础上,对中国男性人口死亡率的Lee-Carter模型各参数进行估计与预测.     

Retrospective Testing of Mortality Forecasting Methods for the Projection of Very Elderly Populations in Australia

The purpose of this paper is to present the results of retrospective tests of various extrapolative methods to forecast adult mortality and very elderly populations for Australia. Direct extrapolation methods tested include the Geometric method, Ediev variant, Lee‐Carter method, BMS variant and a relational model. Indirect methods include the extrapolation of parameters of models fitted to the age profile of death rates and a new method involving the extrapolation of features of death frequency distributions namely the modal age and concentration. The geometric, Ediev and Lee‐ Carter BMS methods were very successful in projecting death rates and very elderly populations. Differences between these methods were small. The extrapolation of parametric functions proved successful for males but less so for females. Very elderly populations can be viably projected by directly extrapolating death rates by age when rates of decline in death rates show consistent relationships between ages and are stable over time. Copyright © 2016 John Wiley & Sons, Ltd.     

基于层次分析法的死亡率影响因素的分析

通过层次分析法对死亡率的影响因素进行分析，得出经济水平下的国民收入指标对死亡率的影响程度最大，社会结构下的工业化水平指标次之，为保险公司在制定寿险型产品时提供一定的理论依据．     

Alleviation of mortality induced by salicylate and stress

Protection from the deleterious effects of the interaction of environmental stress and salicylate by calcium supplement was investigated in 96 pigmented rats. Within a 2×2×4 factorial design, rats were assigned to groups defined by:A) ad lib access to 1) plain tap water, or 2) 50 mM calcium chloride solution;B) exposure to stressors consisting of daily 10 h periods of 1) 98 dB SPL noise, or 2) confinement precluding movements;C) daily injections of 233, 350, or 410 mg/kg of sodium salicylate or the saline vehicle. For subjects maintained on tap water, weight loss and mortality increased with salicylate levels, with all subjects dying in the group drinking water and injected with 410 mg/kg. Calcium protected all of the subjects in the noise stress group but not in the confined group.     

死亡率和通胀风险下的DC型养老金最优投资

针对非系统性风险(死亡率风险)和系统性风险(通货膨胀风险)在DC型养老金最优投资策略中产生的影响,提出了基于死亡率风险和通货膨胀下对冲负债的DC型养老金最优投资策略问题,其中死亡率危险和通货膨胀风险是相互独立的因素;假设养老金缴费成员退休前将养老金投资于股票市场和银行,通货膨胀、投资股票和银行的收益、成员工资以及养老金负债均为随机过程,死亡率预测采用Lee-Carter模型;建立连续时间下的对冲负债的DC型养老金动态价值模型,结合随机控制理论推出对应的HJB方程,利用Legendre转化法得到基于死亡率和通货膨胀风险下对冲负债的DC型养老金最优投资比例,最后通过数值模拟分析得到最优投资策略随着投资期限的增加受到通货膨胀风险的影响大于死亡率风险所产生的影响。     

Notes on the overwintering Apanteles-Tetrastichus-Lysibia complex (Hymenoptera: Parasitica), parasitoids of the large white butterfly

Apanteles glomeratus (L.) (Hymenoptera: Braconidae) is the main parasitoid responsible for limiting populations of Pieris brassicae (L.) (Lepidoptera: Pieridae), but Tetrastichus galactopus (Ratzeburg) (Hymenoptera: Eulophidae) and Lysibia nana (Gravenhorst) (Hymenoptera: Ichneumonidae), in turn, greatly limit the primary parasitoid population, reducing its potential for constraint of the future pierid population. The patterns of spring emergence of these species from overwintering A. glomeratus cocoon clusters have functional significance. The sex ratio of emerging A. glomeratus is significantly correlated with the cluster size, higher proportions of females emerging from the larger clusters. Non-ovipositional attacks by T. galactopus appear to cause heavy mortality in the Apanteles cocoon clusters. L. nana oviposits in cocoons of A. glomeratus, whatever they contain, and very active female L. nana lay higher proportions of diploid eggs than do lower status females.