《自然-细胞生物学》：延长细胞寿命的内部机制研究

随着年龄的增长，一种分子在人体中的浓度会自然减少，然而，科学家们发现，通过对这种分子实施管理。则可以显著提高细胞的寿命。新发现发表在日前在线出版的《自然-细胞生物学》期刊上，清楚地显示出通过何种努力可以延长某种特定细胞的生命。     

银杏对果蝇寿命的影响

银杏对果蝇寿命的影响赵伯涛,张卫明（内贸部南京野生植物综合利用研究所）银杏作为古老的保健珍品,其滋补强壮及抗衰老作用历来引入注目,各国对银杏的研究方兴未艾,各种银杏食品和药品纷纷推向市场。我们在开发银杏食品的同时,用银杏浆汁对果蝇进行了实验研究,以探...     

不同保鲜液对郁金香切花保鲜及其贮藏的影响

 本文研究了不同保鲜液及贮藏20-40天后对郁金香切花瓶插寿命的影响。结果表明：1. 保鲜液延长了切花的插瓶保鲜时间;2. 预处理提高了开花率及开花时间;3. 经一个月以上贮藏,开花率及插瓶保鲜时间明显下降;4. 不同品种的耐贮性能不同。     

博莱霉素A_5、Fe~（2＋）、O_2混合的化学发光研究

利用超弱发光仪测得博莱霉素Ａ５（ＢＬＭＡ５）、Ｆｅ２＋、Ｏ２混合物有微弱化学发光,最大发射波长约为５９０ｎｍ;发光强度随ＢＬＭＡ５或Ｆｅ２＋浓度增大而增强;·ＯＨ清除剂甘露醇对发光无影响;Ｃｕ２＋、ＥＤＴＡ、ＤＮＡ对化学发光均有不同程度的抑制作用。上述结果说明：ＢＬＭＡ５与Ｆｅ２＋、Ｏ２混合可形成某种激发态复合物,并显示该激发态的形成与·ＯＨ无关,提示该激发态复合物可能是ＢＬＭＡ５降解ＤＮＡ的启动因子。     

不同pH条件下R-藻红蛋白和C-藻蓝蛋白荧光寿命的研究

采用自己研制的时间分辨毫微秒荧光谱仪对R-藻红蛋白(R-PE )和C-藻蓝蛋白(C-PC)进行了荧光寿命的测定和研究,并对能量传递过程进行了分析和讨论.测得R-PE的荧光寿命为3.1±0.1ns,C-PC的荧光寿命为1.3±0.1ns,且在pH5—pH9的范围内不变;当pH<5时,两者的荧光寿命都有变短的趋势.我们还测定了R-PE和C-PC混合溶液中R-PE的荧光寿命不变,而C-PC的荧光寿命变长,从而表明存在着R-PE向C-PC的辐射能量传递.     

毫微秒荧光谱仪的自动数据处理系统

本文描述了时间相关单光子毫微秒荧光谱仪的自动数据处理系统,介绍了它的工作原理、设计特点及其应用。     

《应激医学》出版

人类的寿命一直呈现出稳步延长的趋势,据科学家预测,一旦抗衰老新科技研制成功,到2050年,人类寿命至少能延长20年,百岁寿星将不再稀罕。不过,这个福音的背后却包含着许多人们意想不到的变化,到时候,西方工业国家的退休年龄至少要顺延至85岁。     

Influence of host age and host deprivation on longevity, egg load dynamics and oviposition rate in Microplitis rufiventris

Adult size, longevity, egg load dynamics and oviposition ofMicroplitis rufiventris Kok. which began their development in the first, second, third （preferred hosts） or fourth （non-preferred hosts） instar larvae of Spodoptera littoralis （Boisd.） were studied. The parasitoid size was largely determined by the initial host size at parasitism. Non-ovipositing females derived from older hosts lived for longer periods than those derived from younger ones. However, the ovipositing females, irrespective of their size, lived for almost the same periods. At emergence, the oviducts of adult females contain a significant amount of mature eggs available for oviposition for a few hours on eclosion day. Egg load increases during the early phase of adult life. The amount of additional mature eggs and rate of egg maturation per hour was greater for wasps derived from preferred hosts compared with those in females derived from non-preferred hosts. The pattern of egg production in M. rufiventris females depended on the availability of hosts for parasitization. Host-deprived females depleted the egg complement with aging; the longer the host deprivation, the lower the oviduct egg load. Marked reduction in both realized or potential fecundity of host-deprived females was observed following host availability. Host privation for more than 3 days induced a marked deficit fecundity pattern through the female＇ s life. The realized fecundity was determined by the interaction among host availability, the number of eggs that are matured over the female＇ s life span, oviposition rate and host size from which the female was derived. These results suggest that： （i） M. rufiventris wasp is a weak synovigenic species; （ii） the maturation of additional eggs is inhibited once the maximum oviduct egg load is reached; （iii） the egg load of the newly emerged female is significantly less than the realized fecundity; and （iv） because M. rufiventris females oviposit fewer eggs when they begin depleting their egg supply at 3 days, augmentative releases will require release immediately following emergence to ensure the highest parasitization rate in the field.     

补充营养对枹栎象成虫寿命的影响

在饲养笼内分别饲喂枹栎(Quercus serrata Murray)幼果、枹栎嫩枝、清水和10%蔗糖水,以不饲喂任何食物为对照,研究营养补充对枹栎象Curculio haroldi Faust成虫寿命的影响。同时,还研究枹栎象的个体大小和性别对其寿命是否有潜在影响。结果表明:补充不同营养对枹栎象的寿命有显著影响,其中10%蔗糖水组的寿命最长,是其他营养组的3~4倍。另外,虫体大小(即体长)对枹栎象寿命也有显著影响,且雌虫寿命一般比雄性略长,但性别间无显著差异。研究结果说明,营养品质和虫体大小可显著影响枹栎象寿命,进而影响其繁殖以及对寄主植物的危害。