人工培育牛黄对小白鼠离体小肠运动的解痉作用

本文证明培育牛黄对乙酰胆硷与氯化钡所引起的小白鼠离体小肠痉挛有解痉作用。培育牛黄的成份中去氧胆酸具有较强的抗乙酰胆硷与氯化钡作用,其浓度与效应呈直线相关。其成分中的胆酸仅有较弱的抗乙酰胆硷作用,且浓度与效应不呈直线相关,也无抗氯化钡作用。     

Stability of Saxitoxin in 50% Methanol Fecal Extracts and Raw Feces from Bowhead Whales (Balaena mysticetus)

In recent decades, harmful algal blooms (HABs) producing paralytic shellfish toxins (including saxitoxin, STX) have become increasingly frequent in the marine waters of Alaska, USA, subjecting Pacific Arctic and subarctic communities and wildlife to increased toxin exposure risks. Research on the risks of HAB toxin exposures to marine mammal health commonly relies on the sampling of marine mammal gastrointestinal (GI) contents to quantify HAB toxins, yet no studies have been published testing the stability of STX in marine mammal GI matrices. An understanding of STX stability in test matrices under storage and handling conditions is imperative to the integrity of toxin quantifications and conclusions drawn thereby. Here, STX stability is characterized in field-collected bowhead whale feces (stored raw in several treatments) and in fecal extracts (50% methanol, MeOH) over multiple time points. Toxin stability, as the percent of initial concentration (T0), was reported for each storage treatment and time point. STX was stable (mean 99% T0) in 50% MeOH extracts over the 8-week study period, and there was no significant difference in STX concentrations quantified in split fecal samples extracted in 80% ethanol (EtOH) and 50% MeOH. STX was also relatively stable in raw fecal material stored in the freezer (mean 94% T0) and the refrigerator (mean 93% T0) up to 8 weeks. STX degraded over time in the room-temperature dark, room-temperature light, and warm treatments to means of 48 ± 1.9, 38 ± 2.8, and 20 ± 0.7% T0, respectively, after 8 weeks (mean ± standard error; SE). Additional opportunistically analyzed samples frozen for ≤4.5 years also showed STX to be relatively stable (mean 97% T0). Mean percent of T0 was measured slightly above 100% in some extracts following some treatments, and (most notably) at some long-term frozen time points, likely due to evaporation from samples causing STX to concentrate, or variability between ELISA plates. Overall, these results suggest that long-term frozen storage of raw fecal samples and the analysis of extracts within 8 weeks of extraction in 50% MeOH is sufficient for obtaining accurate STX quantifications in marine mammal fecal material without concerns about significant degradation.     

杨梅简易气调保鲜过程中气体成分变化及保鲜效果

以东魁杨梅为试材,研究简易自发气调贮藏(MA)和充氮气调贮藏(NA)条件下,杨梅贮藏小环境中气体成分的变化和对贮藏效果的影响。结果表明:在MA中,乙烯浓度在2d达到高峰;O2前4d浓度急剧下降,后维持在2.48%至1.78%;CO2一直呈上升趋势,试验过程浓度提高了124.3%。在NA中,乙烯高峰出现时间明显推迟、峰高降低;O2浓度维持在2.28%-1.82%,CO2变化与MA相似,浓度提高了131.3%。MA和NA均有效延缓杨梅鲜果的软化变质,减缓果实硬度和总糖的下降速率。贮藏至16d,NA和MA中果实变质率分别比对照下降31.6%和22.5%,硬度比对照增加25.93%和21.98%,总糖含量处理与对照无明显差异。     

野大麦盐胁迫rbcS基因的克隆及序列分析(摘要)(英文)

[目的]研究野大麦盐胁迫rbcS基因的克隆及序列分析。[方法]以盐胁迫下的野大麦幼嫩叶片为试材,根据GenBank中小麦和大麦rbcS基因核酸序列的同源性设计引物,对野大麦基因组DNA进行PCR扩增、回收、连接、转化及测序。[结果]在野大麦的基因组中克隆了2个大小不同的rbcS基因序列rbcS1和rbcS2,长度分别为1252和908bp。rbcS1和rbcS2均由2个外显子和1个内含子组成,外显子长度相等,编码序列为525bp,同源性为96%,编码174个氨基酸;rbcS1和rbcS2内含子大小不同,分别为448和107bp。[结论]该研究为进一步探讨rbcS基因在野大麦耐盐机制中的分子机制奠定了基础。     

含肽肝素渣水解物对早期断奶仔猪免疫功能的影响

本试验研究了含肽肝素渣水解物对早期断奶仔猪免疫器官生长发育、血清IgG含量、淋巴细胞数、腹泻指数以及生产性能的影响。试验表明,肝素渣水解后产生的寡肽可促进仔猪免疫器官发育,提高血清免疫球蛋白浓度、猪瘟抗体OD值和血液中淋巴细胞数,提高了断奶仔猪的免疫功能,降低了仔猪的腹泻指数,并能提高仔猪的日增重和饲料转化率。     

党参小包装饮片养护方法研究

[目的]通过对比不同包装、贮藏条件对党参小包装饮片内外质量的影响,建立适合党参小包装饮片的养护贮藏方法.[方法]党参饮片分别采用聚乙烯塑料、铝箔、牛皮凝膜纸袋3种包装材料包装,做真空/非真空处理后,藏于不同温湿度的环境中,定期考察外观性状、水分、浸出物、多糖及其总黄酮等指标的变化.[结果]前6个月内,各组的检测指标均无明显变化;12个月时,非真空包装样品中的多糖、总黄酮含量均呈显著变化,且室温下贮存的纸袋包装样品出现了虫蛀,色泽变暗、变深的现象;18个月时,除真空包装冷藏处理的各样品以及阴凉条件下的铝箔真空包装样品各检测指标与0个月差异不大外,其余均有明显的性状或含测指标变化.[结论]结合养护成本综合考虑,党参小包装饮片可采用真空塑料或铝箔包装,存放于阴凉干燥处.     

王家沟小流域50a土地利用动态变化分析

以经过50多a水土保持综合治理的王家沟小流域为研究对象,利用其1959—2008年土地利用数据,对该流域土地利用动态变化进行分析。结果表明,调整土地利用结构是王家沟小流域水土保持综合治理的一项关键性措施。     

城区道路景观共生模式研究——以金寨县将军大道为例

对小城镇沿河主干道的道路周边用地和道路中央分隔带进行景观设计和植物配置,将生态学中的共生机制原理运用到景观规划中,将地形、地貌、地物的自然景观,满足人类精神需要的人文景观,道路行车安全的功能景观和谐优化,初步探讨出一种共生机制下的小城镇道路景观共生模式。     

我国中小银行成长性综合评价研究

通过构建商业银行成长性评价体系，利用突变级数法对14家中小银行2007~2010年的成长性进行评价，得出中小银行具有振荡向上的成长趋势，且股份制银行整体成长性优于城市商业银行，但对于影响成长性的各因素，银行间的表现不尽相同。这表明中小银行还需调整经营管理思路来保证成长的稳健和持续。     

Oxidative stress drives divergent evolution of the glutathione peroxidase (GPX) gene family in mammals

The molecular basis for adaptations to extreme environments can now be understood by interrogating the ever-increasing number of sequenced genomes. Mammals such as cetaceans, bats, and highland species can protect themselves from oxidative stress, a disruption in the balance of reactive oxygen species, which results in oxidative injury and cell damage. Here, we consider the evolution of the glutathione peroxidase (GPX) family of antioxidant enzymes by interrogating publicly available genome data from 70 mammalian species from all major clades. We identified 8 GPX subclasses ubiquitous to all mammalian groups. Mammalian GPX gene families resolved into the GPX4/7/8 and GPX1/2/3/5/6 groups and are characterized by several instances of gene duplication and loss, indicating a dynamic process of gene birth and death in mammals. Seven of the eight GPX subfamilies (all but GPX7) were under positive selection, with the residues under selection located at or close to active sites or at the dimer interface. We also reveal evidence of a correlation between ecological niches (e.g. high oxidative stress) and the divergent selection and gene copy number of GPX subclasses. Notably, a convergent expansion of GPX1 was observed in several independent lineages of mammals under oxidative stress and may be important for avoiding oxidative damage. Collectively, this study suggests that the GPX gene family has shaped the adaption of mammals to stressful environments.