假蒟提取物对感染柔嫩艾美耳球虫鸡血液指标的影响

本试验旨在研究假蒟提取物对感染柔嫩艾美耳球虫鸡血液指标的影响。270只1日龄海南文昌公鸡,随机分为6个组,每组3个重复,每重复15只,T1、T2和T3组为对照组(依次分为不感染不给药组、感染不给药组、感染给药组);T4、T5和T6组为假蒟添加组,分别在基础日粮中添加200、400、600mg/kg假蒟提取物粉剂。15日龄时,每组随机抽取30只鸡,除T1组灌服生理盐水外,其他各组鸡均经口接种柔嫩艾美耳球虫卵囊悬液,分别于接种前1d,接种后3、6、9d清晨采血测定其血液指标。结果表明,与感染球虫不给药的T2组相比,假蒟组(T4、T5、T6)可以显著降低感染球虫鸡粪便中球虫卵囊值(P0.05)。假蒟组在感染球虫后第6天,与T1组比,RBC、HGB、HCT、Ca2+、Na+、Cl-、TP、ALB、GLB、TG、CHOL、T4等指标呈下降趋势;但在感染球虫后第9天,TP、GLB含量均显著高于T1组(P0.05);在感染球虫后第6天,假蒟组与对照组相比,ALT、AST浓度水平均显著降低(P0.05)。结果提示,假蒟提取物能提高感染球虫后鸡机体免疫机能,降低肝脏损伤,降低鸡感染球虫后粪便卵囊值,具有一定的抗球虫效果。     

The long-term effects of fire regime on primary production of montane grasslands in South Africa

Natural grasslands deliver essential ecosystem services through plant production, which enhances water supply, nutrient cycling, soil retention and greenhouse gas mitigation. Although the condition of montane grasslands for provision of ecosystem services is maintained by regular annual or biennial burning, controversy exists over the impact of different frequencies and seasons of burning on grassland productivity. The objective of this study was to determine the long-term effects of different burning regimes on primary production and quality of the montane grasslands of the KwaZulu-Natal Drakensberg. There were no significant differences in the mean standing live mass between 30 years of annual winter and biennial spring burning. However, in unburnt areas productivity was 20% lower (118.2?g m?2) than in regularly burnt grassland (144.7–154.5?g m?2). Crude protein did not vary between the annual winter and biennial spring treatments (95–113?kg ha?1), but was significantly lower in unburned areas (45?kg ha^?1). However, an infrequent fire in a protected area caused a temporary spike in crude protein (16%) compared with regular burning (5–10%), which can benefit wildlife. We conclude that montane grasslands can be burnt annually or biennially in the dormant season to promote long-term productivity.     

The influences of ambient temperature and crude protein levels on performance and serum biochemical parameters in broilers

This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28–32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially.     

灵芝孢子受冷等静高压作用破壁提取机理的探讨

按照普通植物种子的情况,推定灵芝孢子的结构有完全充满、部分充满、有大空隙和无种仁4种形式。为此,按照这4种形式分别说明了灵芝孢子受高等静压作用时,孢子壁的破坏方式和灵芝孢子有效成分的溶出方式。     

基于K均值聚类的厚壁组织区域自动提取

桉树是我国南方的速生丰产林,区域提取是定量分析各种组织抑制桉树茎生根原因的重要前提。为此,介绍了基于K均值聚类的在桉树茎切片图像中自适应提取厚壁组织区域的图像处理技术。将桉树茎切片彩色图像转换为CIEL*a*b*彩色空间,用K均值聚类分析算法对描述颜色的a*和b*通道进行聚类分析,提取细胞厚壁,然后填充其中白色的细胞腔,构成完整的厚壁组织区域。实验结果表明,在CIEL*a*b*空间使用该算法可以获得较准确的实验结果。     

茶叶提取物对抗肺癌细胞(A549)体外试验研究

观察表没食子儿茶素没食子酸酯(EGCG)、茶黄素-3、3'-双没食子酸酯(TFDG)、茶黄素(TF)、茶黄素复合物(TFs)、葡萄籽提取物(GrapeSeedExtract,GSE)、松树皮提取物(PineBarkExtract,PBE)、咖啡因(Caf)、槲寄生(VCE)和茶氨酸(The)的体外抗癌活性,通过人肺癌细胞(A549)进行体外试验,结果表明除咖啡因、槲寄生、茶氨酸的作用较小以外其他几种均有很强的促进人肺癌细胞(A549)凋亡的作用,并且EGCG的作用最强,顺序为EGCG、TFs>GSE>PBE、TFDG>TF。用作图法求得EGCG、GSE、PBE、TFDG和TF的IC50值分别为1.01μM、21.91μM、31.01μM、32.87μM和279.67μM。     

朱顶红叶片提取物抑菌效果的初步研究

为开发利用朱顶红提供依据,研究朱顶红叶片提取物对病原真菌的抑菌作用,以石油醚和丙酮为溶剂对朱顶红叶片中的活性物质进行索氏提取,并对其提取物进行了生物测定。结果表明,其活性物质对4种病原真菌菌丝生长都表现出抑制作用,0.06 g/mL以上浓度的抑菌效果明显。相同浓度下的孢子萌发试验结果显示:活性物质除了对枇杷叶斑病菌(Pes-tulotiopsis funerea)的抑制效果较差外,对其他3种病菌孢子的萌发抑制率均在73%以上。     

柱花草浸提液对柑桔幼苗生长的影响

以不同浓度的柱花草（Stylosanthes guianensis）水浸提液根施柑桔(Citrus reticulate Blanco)幼苗,观测柑桔幼苗生长的情况。结果表明,较高浓度的柱花草浸提液对柑桔幼苗生长均有促进作用;柱花草浸提液处理使柑桔植株增高,叶片增多,叶面积增大,生物量增加,植株全磷和全钾量增加。试验结果表明,100 mg.mL-1的柱花草浸提液处理对柑桔幼苗生长的促进作用最佳。     

Phenolic extract of Morchella angusticeps peck inhibited the proliferation of HepG2 cells in vitro by inducing the signal transduction pathway of p38/MAPK

Morchella angusticeps Peck, one of the most popular edible mushrooms, has attracted great attention due to its delicious taste and healthy properties. However, both its biological effects and the possible mechanism of action have not yet been known. We investigated the anti-proliferative activity of the phenolic extract derived from Morchella angusticeps Peck (MPE) against HepG2 human hepatocellular carcinoma cells. Results showed that MPE at non-cytotoxicity doses significantly inhibited the proliferation of HepG2 cells in a dose-dependent manner with inhibitory rates ranging from 18 to 90% (P<0.01). The possible mechanism might be that MPE induced apoptosis through initiating the mitochondrial death pathway by regulating Bax, Bcl-2 and cleaved caspase-3. On the other hand, MPE might trigger cell cycle arrest at G₀/G₁/S phases by managing p21, Cyclin D1, cyclin-dependent kinases-4 (CDK4) and proliferating cell nuclear antigen (PCNA). Additionally, MPE downregulated TRAF-2 and p-p53, while upregulated p-ASK1 and p-p38. Therefore, it could be inferred that MPE might induce the anti-proliferative function to HepG2 cells through the p38/MAPK signal transduction pathway.     

槲树叶提取液对冷藏期间桃品质及抗氧化系统的影响

以生理成熟期‘新泰红’桃果实为试材,分别用0、2.5、5.0、7.5 g/L槲树叶提取液浸泡果实,以蒸馏水为对照,并于0℃冷藏,测定冷藏期间果实可溶性蛋白等品质指标以及酶活力与活性氧等物质,探讨槲树叶提取液对采后桃果实贮藏品质的影响。结果表明:槲树叶提取液处理能够有效延缓冷藏期间桃果实冷害指数升高以及硬度下降,使整个冷藏期间果实可溶性蛋白、可溶性糖、维生素C含量维持相对较高水平,并且能够有效延缓膜脂过氧化产物(丙二醛)以及活性氧物质(超氧阴离子自由基、过氧化氢和羟基自由基)积累;同时,槲树叶提取液处理还能够显著抑制果实多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)活性,从而延缓冷藏期间桃果实褐变程度。综上所述,槲树叶提取液处理能够缓解冷藏期间桃果实冷害症状,以5.0 g/L槲树叶提取液处理效果最为明显。