苦瓜总皂甙含量测定及超声提取最佳条件的研究

建立了苦瓜总皂甙的超声提取和分光光度测定方法,并优化了超声提取的提取温度、乙醇浓度、料液比和提取时间等因素。结果显示,超声波提取法最佳工艺组合为:70%乙醇,液料比为30∶1,振荡频率为60%,70℃超声提取30 m in/次,重复提取2次;且分光光度测定法操作简便、快速、准确,可作为苦瓜制品提取及质量评价方法。     

农村中小学现代远程教育资源利用的问题与策略

随着农村中小学现代远程教育工程的逐步实施和深入,农村中小学在利用农村远程教育资源（以下简称农远资源）的过程中也暴露出越来越多的问题。针对农远资源在农村中小学教育中利用率低的问题,在做了相关调查的基础上,分析了农村中小学农远资源利用中存在的弊端,为提高农远资源的利用率提出了相关的解决策略。     

广西甘蔗新品种区试柳州点7个甘蔗新品种DTOPSIS法综合评价

[目的]对7个甘蔗新品种(系)的田间表现进行综合评价,筛选优良品种,为其在柳州蔗区的推广应用提供参考依据.[方法]在柳州蔗区条件下,对参与广西甘蔗新品种区试的7个甘蔗新品种进行田间一年新植和一年宿根品比试验,并采用DTOPSIS法对其表现进行综合评价.[结果]在7个参试品种中,以桂辐98/296的宿根萌苗率、分蘖率、有效茎数、蔗茎产量、蔗糖分和产糖量表现最好,其他品种表现无明显规律.桂辐98/296、桂糖04/120、玉林1号的综合性状优于对照新台糖22号,而柳城03/362、桂糖04/2278和桂糖02/496低于对照新台糖22号.7个甘蔗品种的C值从高到低排序为桂辐98/296、桂糖04/120、玉林1号、桂糖04/2278、新台糖22号、柳城03/362、桂糖02/496.[结论]桂辐98/296、桂糖04/120、玉林1号适宜在广西柳州地区及气候相似蔗区大面积推广应用,而桂糖04/2278、柳城03/362、桂糖02/496则不宜在该类型蔗区推广应用.     

沼渣在秋马铃薯上的应用试验

采用沼渣作底肥并与普通农家肥作比较,总结其对秋马铃薯生产的作用及其生产施用量,结果表明:施用沼渣作底肥,对秋马铃薯的出苗率有所提高,对块茎的形成、膨大、色泽都有显著的效果,为大面积推广提供了试验依据。     

低温弱光对CMS三系辣椒幼苗形态指标与冷害指数的影响

以辣椒CMS三系的不育系、恢复系与相应杂交一代幼苗为材料,研究了辣椒幼苗对低温弱光及其恢复过程的响应。结果表明:低温弱光胁迫下,辣椒幼苗植株生长减缓或停止,外部形态出现部分变化。低温弱光处理10天后,与对照相比各试验材料株高增加缓慢,基本停止生长,但恢复系表现出较好的低温弱光耐受性。从外部形态与冷害指数综合来看,杂交种与恢复系受害程度明显较轻。     

Regulatory effect of Panax notoginseng saponins on the oxidative stress and histone acetylation induced by porcine circovirus type 2

Porcine circovirus type 2 (PCV2) exists widely in swine populations worldwide, and healthy PCV2 virus carriers have enhanced the severity of the infection, which is becoming more difficult to control. This study investigated the regulatory effect of Panax notoginseng saponins (PNS) on the oxidative stress and histone acetylation modification induced by PCV2 in vitro and in mice. In vitro, PNS significantly increased the scavenging capacities of superoxide anion radicals (O₂^•-) and hydroxyl radicals (^•OH) and reduced the content of hydrogen peroxide (H₂O₂) induced by PCV2 in porcine alveolar macrophages (3D4/2). In addition, PNS decreased the protein expression level of histone H4 acetylation (Ac-H4) by increasing the activity of histone deacetylase (HDAC) in PCV2-infected 3D4/2 cells. In vivo, PNS enhanced the scavenging capacities of ^•OH and O₂^•− and reduced the content of H₂O₂ in the spleens of PCV2-infected mice. PNS also reduced the protein expression level of histone H3 acetylation (Ac-H3) by reducing the activity of histone acetylase (HAT) and increasing the activity of HDAC in the spleens of PCV2-infected mice. PCV2 infection activated oxidative stress and histone acetylation in vitro and in mice, but PNS ameliorated this oxidative stress. The research can provide experimental basis for exploring the antioxidant effect and the regulation of histone acetylation of PNS on PCV2-infected 3D4/2 cells and mice in vitro and in vivo, and provide new ideas for the treatment of PCV2 infection.     

Lipid metabolism is improved by L-carnitinein semi-starved rats fed on high fat diet

AIM: To investigate the effects of exogenous L-carnitine on lipid metabolism in semi-starved rats fed on high fat diet. METHODS: The semi-starved rats were restricted half in calorie intake on high fat diet for 2 week. L-carnitine was supplied at dose of 250 mg/kg·bw. The changes of plasma carnitine concentration, urinary excretion of ketone body, serum lipase activity, muscle carnitine palmitoyl transferase activity, triglyceride secretion and clearance rate were measured. RESULTS: The results showed that the concentration of plasma free carnitine increased significantly in carnitine supplemented rats compared to normal and semi-starved rats.The activities of muscle carnitine palmitoyltransferase and serum lipase were significantly enhanced in carnitine supplemented rats. The triglyceride secretion rate (TGSR) was also improved remarkably by carnitine supplementation. Meanwhile, the urinary excretion of ketone body was reduced significantly in carnitine supplemented rats compared to semi-starved rats. CONCLUSION: It is concluded that carnitine supplementation can significantly increase the plasma concentration of free carnitine and accelerate the lipid metabolism in semi-starved rats fed on high fat diet.     

蔗叶机械化粉碎还田负面效应分析与控制

通过对甘蔗叶粉碎还田前后土壤结构、营养成分以及还田技术方式进行分析和试验对比,初步探讨其主要原因,并提出了从种植、管理、技术手段等多方面相结合的控制技术措施。     

城市生活污水对斑马鱼肝脏组织结构和NF-κB基因表达的影响

为评价生活污水的直接排放对水体中的鱼类的毒性效应,将斑马鱼暴露在25%、50%、100%浓度的污水中,在实验持续到第4天、7天和14天后分别采集各实验组和对照组鱼的肝脏,制作肝脏组织切片,观察肝组织结构的变化。结果发现:随着污水浓度的增大和时间的延长,肝细胞病变程度加深,肝窦隙扩张,细胞核肿大甚至裂解消失,胞质疏松,空泡明显增加。利用RT-PCR分析NF-κB基因表达变化发现斑马鱼经25%、50%、100%浓度生活污水处理不同时间后,表达水平均明显上调。研究表明生活污水的直接排放将对水体中的鱼类的肝脏产生毒性效应并可能出现NF-κB的激活,促进炎症反应的发生。     

加味玉屏风汤对免疫抑制小鼠免疫器官的保护效应

应用动物试验和病理组织学方法,研究了传统中药方剂加味玉屏风汤对环磷酰胺所致免疫抑制小鼠脾和胸腺等免疫器官的保护作用。结果表明,加味玉屏风汤能明显拮抗环磷酰胺所致脾白髓、骨髓造血组织和胸腺淋巴细胞容量下降（Ｐ〈０．０１）,能显著升高下降的胸腺和脾指数（Ｐ〈０．０１）及减少的外周血白细胞和体重（Ｐ〈０．０１）;同时对健康小鼠以上指标也有不同程度的促进作用,提示加味玉屏风汤对脾和胸腺等免疫器官具有一定的