不同品种菊花和贵州产野菊花中木犀草素的含量比较

目的测定并比较不同品种菊花和贵州产野菊花中木犀草素的含量。方法用高效液相色谱法测定木犀草素的含量。色谱柱为ODS柱（4．6mm×250mm,5μm）,流动相为甲醇-水-冰醋酸（体积比45：55：0．4）,检测波长为254nm,流速1．0mL／min。结果7个菊花样品的木犀草素含量,以贵州野菊花的木犀草素含量最高（3．876mg／g）,杭菊的木犀草素含量最低（0．302mg／g）。结论贵州产野菊花中木犀草素的含量均高于其他品种菊花,具有较高的药用价值。     

高速逆流色谱法分离凤尾草中的芹菜素和木犀草素

建立了高速逆流色谱分离纯化芹菜素和木犀草素的方法。两相溶剂系统为氯仿-甲醇-水（4：3：2）,上相为固定相,下相为流动相进行洗脱。从100mg粗提物中一步分离得到17．0mg芹菜素和22．5mg木犀草素,经高效液相色谱分析,纯度分别为92％和96％。其化学结构由1H和13CNMR鉴定。     

岩生植物金发草对作物的化感效应

采用生物测定法研究金发草根、茎、叶水浸提液对水稻、小麦、油菜和莴苣等4种受体植物的化感作用。结果表明,金发草根、茎、叶水浸提液对4种受体植物种子萌发和幼苗生长均具化感作用,且随着水浸提液浓度的增高而增强。除水稻外,小麦、油菜、莴苣的发芽速率均受金发草水浸提液的显著抑制,但对最终发芽率影响不显著,说明金发草对植物种子萌发的化感作用主要是延迟种子发芽时间;金发草对作物幼苗生长的化感作用总体上表现为促进地上部分生长而抑制地下部分的生长。受体植物不同发育期对金发草化感作用的敏感程度不同,幼苗期高于萌发期;金发草叶的化感作用最强,其综合效应分别为根与茎的2.14倍和2.56倍。     

HPLC同时测定药用白菊花中绿原酸、木犀草素、芹菜素和金合欢素

采用高效液相色谱法(HPLC)建立同时测定药用白菊花中绿原酸、木犀草素、芹菜素和金合欢素含量的方法,样品采用离子液体分散液相微萃法提取。采用Phenomenex C18色谱柱(250 mm×4.6 mm,5μm);流动相:甲醇-0.2%冰醋酸溶液(65∶35);检测波长350 nm;柱温35℃;流速0.8 mL/min。绿原酸、木犀草素、芹菜素和金合欢素的质量浓度与峰面积分别在0.0005~100(r=0.9999)、0.00095~190(r=0.9999)、0.0008~160(r=0.9997)、0.00061~122μg/mL(r=0.9996)呈良好的线性关系;回收率分别为90.52%~100.44%、90.88%~98.58%、94.40%~98.82%、93.68%~100.54%。该方法快速,简便,重复性好,适合于同时测定药用白菊花中绿原酸、木犀草素、芹菜素和金合欢素的含量。     

赤豆种子萌发中幼苗酰脲含量及尿囊素酶活力变化动态

赤豆种子萌发过程中,幼苗迅速合成酰脲,在酰脲含量达到最大值前,尿囊酸含量高于尿囊素含量,子叶合成酰脲最迅速;酰脲含量达到最大值后,茎带叶的酰脲含量最高。幼苗累积酰脲在品种间相似。种子萌发过程中,幼苗尿囊素酶活力迅速呈线性增加,且与酰脲含量变化趋势一致。幼苗尿囊素酶较耐热。     

不同季节灰毡毛忍冬茎叶中绿原酸和木犀草苷含量的分析

目的：比较分析不同季节的灰毡毛忍冬茎叶中绿原酸和木犀草苷的含量,为综合利用茎叶资源提供参考依据.方法：采用蒸制晒干法对灰毡毛忍冬的茎叶进行干燥处理,利用超声波法提取样品中的绿原酸和木犀草苷并通过高效液相色谱法进行含量测定.结果：绿原酸和木犀草苷含量在不同季节的灰毡毛忍冬茎叶中差异明显.绿原酸含量依次为花＞叶＞茎,以秋季（11月份）叶片样品中的绿原酸含量最高（3.031％）,是花蕾中含量的96％;木犀草苷含量总体趋势为叶＞花和茎,以冬季（2月份）叶片样品中的含量最高（0.558％）,是花蕾中含量的4.6倍;二者均高于2010版《中国药典》对山银花和金银花指标物质含量的规定.结论：秋冬季节对灰毡毛忍冬进行休眠期整型修剪,副产物叶片资源丰富,药源成分充足,具有广阔的开发应用前景.     

土壤有效硅对大豆生长发育和生理功能的影响

人工调节土壤有效硅含量及盆栽试验,研究土壤有效硅对大豆生长发育和生理功能的影响。结果表明,土壤有效硅含量在55．1～202.8mg·kg^-1范围内,随着土壤有效硅含量的提高,大豆种子萌发过程中蛋白酶和脂肪酶活性升高,淀粉酶活性无显著变化,呼吸速率加快,种子活力升高,萌发速度加快,种子萌发率无显著变化;幼苗生长过程中叶片叶绿素含量无显著变化,光合速率加快,根系活力、硝酸还原酶活力升高,蒸腾强度减弱,水分利用效率和叶含水量升高,抗旱保水能力提高。大豆幼苗含硅量与土壤有效硅含量呈线性正相关趋势(r=0．994)。土壤有效硅含量大于2028mg·kg^-1,生理功能不再显著变化,说明土壤中的硅被大豆吸收后,改善了大豆萌发种子和幼苗的生理功能,使种子萌发和幼苗生长加快。     

不同产地野菊花中黄酮类成分含量的HPLC分析

野菊花为菊科(Compositae)植物野菊[Dendranthema indicum (L.) Des Moul.]的头状花序,具有清热解毒和疏风散热等功效.黄酮类化合物为野菊花最主要的有效成分之一,最早从野菊花中分离出的黄酮类化合物为木犀黄酮苷,此后相继得到刺槐素、木犀草素、芹菜素和蒙花苷等黄酮类化合物,以蒙花苷和木犀草素含量最高,其中蒙花苷含量是野菊花药材的主要质量检测指标[1].     

HPLC-MS/MS法测定黄山贡菊花、叶和茎中酚类物质

采用HPLC-MS/MS检测技术分析了黄山贡菊花、叶、茎中酚类物质。结果表明,黄山贡菊花、叶、茎中酚类物质主要为黄酮及酚酸类化合物,其中贡菊花中含有13种黄酮类化合物,9种酚酸类化合物;叶中含有11种黄酮类化合物,6种酚酸类化合物;茎中含有8种黄酮类化合物,5种酚酸类化合物。贡菊花、叶、茎中共有的酚性成分包括:绿原酸、1,5-二咖啡酰奎尼酸、3,5-二咖啡酰奎尼酸、4,5-二咖啡酰奎尼酸、芹菜素-6-C-木糖-8-C-葡萄糖、芹菜素-6-C-葡萄糖-8-C-阿拉伯糖、芹菜素-6-C-阿拉伯糖-8-C-葡萄糖、木犀草苷、木犀草素-7-O-葡萄糖醛酸苷、香叶木素-7-O-6"-丙二酰-葡萄糖苷、金合欢素-7-O-6"-丙二酰-葡萄糖苷。金合欢素-7-O-半乳糖苷存在于贡菊茎、叶中,而在贡菊花中未发现;芹菜素-7-O-葡萄糖醛酸苷只存在于贡菊叶中,在贡菊花和茎中均未发现。     

玉米AGO基因的克隆与表达分析

以玉米自交系‘昌7-2’三叶期前后2个时间点(种子萌发后5d和8d)幼苗不同组织部位的总RNA为研究对象,采用实时荧光定量PCR技术,对玉米中6个Argonaute(AGO)蛋白家族基因(AGO1、AGO2、AGO4、AGO5、AGO7和AGO10)在幼苗不同发育时期及不同组织部位的表达谱进行了研究。结果表明:(1)AGO1、AGO2、AGO4和AGO7在种子萌发后5d和8d幼苗不同组织中均有表达,种子萌发后5d幼苗中的平均表达量均高于萌发8d的幼苗,且在地上部分新生组织或细胞分裂比较旺盛的组织中表达较多,表明AGO1、AGO2、AGO4和AGO7可能在玉米幼苗发育早期的分生组织分裂生长中发挥调控作用。(2)AGO5和AGO10只在叶片和茎尖中表达,其他组织中不表达;其中AGO5主要集中在新生叶和种子萌发后8d的茎尖中,AGO10在玉米叶发育过程中可能存在着迁移的现象。     

Embryo and Endosperm Function and Failure inSolanumSpecies and Hybrids

Although the importance of the endosperm as a food store inmany angiosperm seeds is well known, its significance duringearly embryogenesis has been neglected. In many interspecifichybrids, and in some other situations, embryos do not developfully and abort. It has often been stated that this is causedby the endosperm failing to conduct sufficient nutrients tothe embryo, but seldom has it been suggested that the endospermactively controls most of the early stages of morphogenesisof the embryo. Information gleaned from a broad survey of theliterature, combined with additional evidence presented here,obtained fromSolanum incanumand interspecific hybrids, indicatethat the endosperm is dynamic and very active in regulatingearly embryo development. This requires highly integrated geneticcontrol of rapidly changing metabolism in the endosperm. Ininterspecific hybrids, lack of coordination may cause unbalancedproduction of growth regulating substances by the endospermand hence abortion of the embryo, or even unregulated productionof nucleases and proteases resulting firstly in autolysis ofthe endosperm and then digestion of the embryo. The endospermmay thus serve to detect inappropriate hybridization of speciesor ploidy levels and so prevent waste of resources by producingseeds that would result in sterile hybrids or unthrifty subsequentgenerations. This discriminatory function of the endosperm hasdiminished during evolution and domestication of the crop plantSolanummelongenaL.Copyright 1998 Annals of Botany Company Solanum, embryo morphogenesis, endosperm, hybrid, seed development.     

Pragmatic Women and Body Politics and Maternities and Modernities: Colonial and Postcolonial Experiences in Asia and the Pacific

Pragmatic Women and Body Politics. Margaret Lock and Patricia A. Kaufert. eds. Cambridge, UK: Cambridge University Press, 1998. xii +364 pp.
Maternities and Modernities: Colonial and Postcolonial Experiences in Asia and the Pacific. Kalpana Ram and Margaret Jolly. eds. Cambridge, UK: Cambridge University Press, 1998. xiv. 305 pp.     

HIFs and tumors--causes and consequences

For most organisms oxygen is essential fo life. When oxygen levels drop below those required to maintain the minimum physiological oxygen requirement of an organism or tissue it is termed hypoxia. To counter act possible deleterious effects of such a state, an immediate molecular response is initiated causing adaptation responses aimed at cell survival. This response is mediated by the hypoxia-inducible factor-1 (HIF-1), which is a heterodimer consisting of an alpha- and a beta-subunit. HIF-1 alpha protein is stabilized under hypoxic conditions and therefore confers selectivity to this response. Hypoxia is characteristic of tumors, mainly because of impaired blood supply resulting from abnormal growth. Over the past few years enormous progress has been made in the attempt to understand how the activation of the physiological response to hypoxia influences neoplastic growth. In this review some aspects of HIF-1 pathway activation in tumors and the consequences for pathophysiology and treatment of neoplasia are discussed.     

Morphological and constitutional features and self-esteem in children and adolescents

Studies of human constitution and mental features are traditionally among the main concepts of anthropological research. In this research, we attempted to discover connections between morphological and constitutional features and self-esteem in children and adolescents. Such a connection was discovered in some studied age groups. The obtained results could serve as a basis for further studies in this field.     

白蚁与动物及微生物的共生类型及其机制

综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生（宾主共栖和异种共栖）、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌（原生动物、细菌、真菌和放线菌）和外生菌（蚁巢伞菌等）间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用（如纤维素酶）及今后研究物种间的协同进化提供了基础资料。