金斑蝶生物学与规模化饲养的初步研究

记述了金斑蝶Danaus chrysippus chrysippus(Linnaeus)的形态特征、生物学特性与规模化饲养的方法.该蝶在海南尖峰岭地区全年发生、世代重叠,1年发生15代左右,完成1个世代冬季需29～37d,夏季14～18d.成虫抗逆性与生命力强,耐高温,嗜食的寄主植物有马利筋Asclepias curassavica L.和牛角瓜Calotropis gigantean(L).金斑蝶色彩艳丽、飞翔姿态缓慢优美,宜在生态蝴蝶园与喜庆等场合放飞,良好的生态环境是金斑蝶规模化饲养成功的关键,而幼虫饲养是它规模化饲养的重要环节.成虫卵散生,幼虫5龄,初孵幼虫宜室外套网袋饲养,5龄后期用塑料盆室内饲养并使之化蛹于盆盖上,将盆盖挂入羽化室内,通过空调和喷雾装置温度控制在25～28℃,湿度控制在60～80%,使蛹能正常发育和羽化.     

沙蒿木蠹蛾生物学特性研究

沙蒿木蠹蛾Holcocerus artemisiae Chou et Hua是危害油蒿Artemisia ordosica Krasch和籽蒿A. sphaerocephala Krasch的重要钻蛀性害虫, 以幼虫蛀食根部, 导致寄主植物长势衰弱甚至死亡。为有效控制其危害, 我们对该虫形态和生物学特征结合野外调查和室内饲养观察进行了研究。结果表明： 在宁夏, 该虫2年发生1代, 以幼虫在被害油蒿根部越冬; 老熟幼虫于5月中旬从受害根部钻出, 在周围的沙土里结茧化蛹, 蛹期平均19.5±3.5 d; 成虫始见于6月初, 终见于8月末, 期间经历3次羽化高峰, 分别为6, 7, 8月的上旬。成虫羽化主要在14:00-17:00, 整个过程持续30~45 min; 羽化当日即可交配, 交配时间为20:00-21:00, 高峰期为20:30左右; 雄虫有2次交尾现象。雄虫寿命2~3 d, 雌虫寿命1~3 d, 极少4 d。雌雄性比约为1∶2.16。卵初见于6月中旬, 初孵幼虫初见于6月下旬。幼虫常单独危害, 且具有转移危害的习性, 蛀食坑道不规则。5-9月, 油蒿受害率为11%~44%, 平均24%, 株虫口密度为0.13头/株。幼虫对油蒿的树龄和地径有较明显的选择性, 主要危害1~4年生、 地径16~34 mm的油蒿。沙蒿木蠹蛾生物学特征的系统研究为其控制措施的制定提供了科学依据。     

陕西凤翔孙家南头秦墓出土人骨中C和N同位素分析

本文对陕西凤翔孙家南头秦墓出土的春秋战国时期人骨中C和N稳定同位素组成进行了测试分析。结果表明: 人骨样品均可用于食谱分析; 由δ13C和δ15N值综合分析可知, 春秋战国时期陕西凤翔地区秦先民是以C4类植物为主食、辅以少量肉食的杂食性食谱; 经济模式可能为农业与畜牧兼营, 以种植黍、粟类等旱地作物的农业形式为主, 并辅以驯养牲畜; 根据墓主与殉人的δ13C和δ15N值对比分析, 推测殉人可能是与墓主饮食方式较为相近的姬妾或仆从之类的人;春 秋中期至战国晚期秦先民的食物结构较为稳定, C4植物比例与δ15N发生变化的原因可能与当时历史的变迁与社会的发展有一定的关系。     

施氮肥对落叶松和水曲柳人工林土壤动物群落的影响

土壤动物对环境变化反应敏感, 全球变化导致土壤氮(N)有效性增加将影响土壤动物群落结构和功能。本文以落叶松(Larix gmelinii)和水曲柳(Fraxinus mandshurica)人工林为研究对象, 通过施肥处理, 在不同季节和土层取样, 研究土壤N有效性增加对土壤动物的数量、类群数和不同功能团的影响。结果表明: (1) 施肥影响两林分土壤动物密度, 导致当年密度增加, 翌年则下降, 这种先增加后降低的趋势在不同土层中均表现出来; (2) 施肥增加了两林分土壤动物类群数, 其中落叶松林分从34类增加到43类, 水曲柳林分从43类增加到48类; (3) 施肥改变了两林分不同食性土壤动物的密度, 腐食性土壤动物数量降低、植食性数量增加、捕食性数量变化不明显。这些结果说明: 土壤N有效性增加显著影响两林分土壤动物群落结构, 可能改变地下碳分配格局和养分循环过程。     

Intra-specific isotope variations of franciscana dolphin Pontoporia blainvillei regarding biological parameters and distinct environments

The franciscana dolphin Pontoporia blainvillei is the most endangered small endemic cetacean species of the southwestern South Atlantic Ocean. We assessed intra-specific variation in the diet of franciscana regarding biological parameters (sex, total body length, age class and sexual maturity) and between distinct environments (open marine area vs. an area adjacent to an estuary) from the Buenos Aires coast, Argentina, using both stable isotopes and stomach content analysis. We found a significant isotopic enrichment in ¹⁵N in neonates and nursing calves, representative of the lactation period. We found differences in the diet of franciscana between dolphins from the open marine area and dolphins living in waters influenced by the estuary, by both diet estimating methods. The lower δ¹⁵N values in dolphins living in waters adjacent to the estuary could be associated with a higher consumption of small sizes of the striped weakfish (Cynoscion guatucupa), which has lower isotope values than the larger sizes consumed in the open marine area. This trophic differentiation between locations is in agreement with the existence of two genetically distinct populations recently found in the study area. This study reveals geographical variations in the diet of franciscana dolphin, supporting the new delineation of distinct franciscana populations in Argentine waters. Considering the small home range and the limited movement pattern of the species, the population living near the estuary would likely need protection due to its low level of genetic diversity and feeding preferences. Therefore, the preservation and conservation of the mentioned habitat is recommended to ensure population viability of franciscana in the region.     

长江口两种重要石首鱼类的摄食习性

通过对2006年夏、秋季在长江口及其毗邻海域采集的575尾白姑鱼(Argyrosomus argentatus)和1089尾小黄鱼(Pseudosciaena polyactis)胃含物样品的分析,利用多元统计分析方法,研究了它们的摄食习性以及随栖息地、季节和体长的变化规律。结果表明:该水域的白姑鱼是底栖动物食性,小黄鱼是混合动物食性,甲壳类在它们食物中均占83%以上的比例,2种石首鱼类的食物重叠系数为0.55。由于摄食的优势饵料种类的差异,使这2种石首鱼类之间不存在严重的食物竞争。与20世纪80年代的研究结果相比,两种石首鱼类所摄食的鱼类的比例均有所下降。结果还表明:白姑鱼的摄食习性较为稳定,受栖息环境、季节以及体长变化的影响较小;而小黄鱼随栖息环境、季节以及体长的变化较大,且109mm是其发生食性转换的一个关键的临界体长。     

Flowering Patterns in a Seasonal Tropical Lowland Forest in Western Amazonia

The phenological behavior of many tropical plant species is highly dependent on rainfall, but these plants may also respond to changes in photoperiod. Without a better knowledge of the proportion of species responding to different factors, it is difficult to predict how global climate change may affect natural ecosystem processes. The aim of this study was to describe flowering patterns for more than 100 species in Tinigua Park, Colombia, and to propose which factors may trigger flower production ( e.g. , rainfall, temperature, cloud cover, and photoperiod). Data gathered in 5.6 km of phenological transects during 4 yr and complementary information indicated that the vast majority of species showed intraspecific synchronization, and annual production was the most common pattern, followed by episodic frequency. The annual patterns were common in tree species, while episodic patterns were common in lianas. Simple and multiple regression analyses suggested several aspects of photoperiod as the most likely triggers for flowering in most species. However, the fact that many of these species produce flowers in different periods each year, suggests that the proportion of species responding to photoperiodic cues is less that 23 percent in this community. The flowering times of taxonomically related species seldom showed significantly staggered distributions; however they do not necessarily occur at the same time, suggesting that flowering patterns are not strongly constrained by phylogeny.     

饮食疗法对妊娠期糖尿病孕妇血脂代谢动态变化的研究

目的:探讨脂代谢紊乱在妊娠期糖尿病(GDM)中的作用,为妊娠期糖尿病的预防及指导临床干预提供理论依据。方法:观察妊娠期糖尿病患者和糖耐量正常孕妇血脂水平及胰岛素抵抗程度差异,分析妊娠期糖尿病患者饮食治疗前后的血脂及炎症标志物的动态变化,于孕12W、24W及36W分别抽取两组孕妇空腹静脉血,测定糖、脂代谢指标及炎症标志物水平,计算血浆致动脉粥样硬化指数(atherogenic index of the plasma,AIP);应用稳态模型胰岛素抵抗指数(HOMA-IR)及胰岛分泌功能指数(HBCI),评价胰岛素抵抗指数(IR)程度及胰岛功能。结果:(1)GDM组的C肽、FINS、HOMA-IR明显高于糖耐量正常组(normal glucose tolerance,NGT)组(p0.05),GDM组HBCI指数低于NGT组(p0.05)。(2)干预组与对照组比较,12W时,TC、TG、HDL、LDL差异均无统计学意义(p0.05);24W及32W差异均有统计学意义(p0.05),均较对照组高。(3)对GDM组中TC、TG、HDL、LDL、AIP、hs-CRP、N及WBC值进行分析,TG、TC、LDL、AIP、hs-CRP、N及WBC值24W较36W及12W高(p0.05);HDL水平24W较36W及12W低(p0.05)。(4)NGT组中TG、TC、LDL、AIP、hs-CRP、N及WBC值36W较24W及12W高(p0.05);HDL水平36W较24W及12W高(p0.05)。结论:GDM孕妇存在着明显的胰岛素抵抗和胰岛β细胞分泌功能受损。GDM孕妇合并较正常妊娠更为严重的炎症反应,血脂水平明显升高,饮食治疗后对改善IR有益,提示在妊娠期糖尿病患者中,通过适当的饮食治疗进而对血糖及血脂的调整可以显著减少母儿并发症。     

饮食和生活习惯与胃癌的相关性研究进展

胃癌是起源于胃粘膜上皮细胞的恶性肿瘤。近年来,虽然大部分国家胃癌发生率呈下降趋势,但我国胃癌的发病率和死亡率仍居高不下。胃癌的发生是多因素共同参与的复杂过程,如与种族、遗传、年龄、性别、幽门螺旋杆菌感染、饮食等因素相关,其中饮食及生活习惯被认为与胃癌的发生关系密切。而且早期胃癌的预后相对良好,降低发生率是防治胃癌的一项关键措施。因此,通过了解饮食及生活习惯因素与胃癌之间的关系,可以加强胃癌的一级预防,从而改善胃癌患者预后。本文就高盐、高脂饮食,蛋白质、蔬菜水果摄入以及吸烟、饮酒等因素与胃癌关系的研究进展进行综述,以期对胃癌的预防奠定一定基础。