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71.
Raddeanin A is one of the triterpenoid saponins in herbal medicine Anemone raddeana Regel which was reported to suppress the growth of liver and lung cancer cells. However, little was known about its effect on gastric cancer (GC) cells. This study aimed to investigate its inhibitory effect on three kinds of different differentiation stage GC cells (BGC-823, SGC-7901 and MKN-28) in vitro and the possible mechanisms. Proliferation assay and flow cytometry demonstrated Raddeanin A’s dose-dependent inhibitory effect and determined its induction of cells apoptosis, respectively. Transwell assay, wounding heal assay and cell matrix adhesion assay showed that Raddeanin A significantly inhibited the abilities of the invasion, migration and adhesion of the BGC-823 cells. Moreover, quantitative real time PCR and Western blot analysis found that Raddeanin A increased Bax expression while reduced Bcl-2, Bcl-xL and Survivin expressions and significantly activated caspase-3, caspase-8, caspase-9 and poly-ADP ribose polymerase (PARP). Besides, Raddeanin A could also up-regulate the expression of reversion inducing cysteine rich protein with Kazal motifs (RECK), E-cadherin (E-cad) and down-regulate the expression of matrix metalloproteinases-2 (MMP-2), MMP-9, MMP-14 and Rhoc. In conclusion, Raddeanin A inhibits proliferation of human GC cells, induces their apoptosis and inhibits the abilities of invasion, migration and adhesion, exhibiting potential to become antitumor drug.  相似文献   
72.
73.
1植物名称 长唇羊耳蒜(Liparis pauliana Hand.-Mazz.). 2材料类别 种子。  相似文献   
74.
通过施用不同类型的杀螨剂对苹果山楂叶螨Tetranychus viennensis和天敌塔六点蓟马Scolothrips takahashii的影响进行分析,结果表明,15%哒螨灵EC(0.4 mL/L)、73%炔螨特EC(0.5 mI/L)表现出较好的速效性和持效性,但是对塔六点蓟马有一定的杀伤作用,240 g/L螺螨酯SC(0.2 mL/L)、5%唑螨酯SC(0.4 mL/L)对山楂叶螨相对防效较好.对塔六点蓟马影响较小,500 s/L四螨嗪SC(0.2 mL/L)速效性较差,但对天敌安全,20%甲氟菊酯EC(0.5 mL/L)对山楂叶螨防治效果差,且对天敌杀伤率始终较高,从而可能造成山楂叶螨的爆发.复配药剂10%阿维·四螨SC(0.67 mL/L)综合了单剂的优点,15.6%阿维·丁醚EC(0.5 mL/L)、6%阿维·哒EC(0.5 mL/L)相对单剂对天敌杀伤率有所降低,1.8%阿维·甲氰EC(0.83 mL/L)则主要表现出单剂甲氰菊酯相同的特点.  相似文献   
75.

Background

Several angiostrongyliasis outbreaks have been reported in recent years but the disease continues to be neglected in public health circles. We describe an outbreak in Dali, southwest China in order to highlight some key problems for the control of this helminth infection.

Methodology/Principal Findings

All available medical records of suspected angiostrongyliasis patients visiting hospitals in Dali in the period 1 October 2007–31 March 2008 were reviewed, and tentative diagnoses of varying strengths were reached according to given sets of criteria. Snails collected from local markets, restaurants and natural habitats were also screened for the presence of Angiostrongylus cantonensis. A total of 33 patients met criteria for infection, and 11 among them were classified as clinically confirmed. An additional eight patients were identified through a surveillance system put in operation in response to the outbreak. The epidemic lasted for 8 months with its peak in February 2008. Of the 33 patients, 97.0% complained of severe headache. 84.8% patients had high eosinophil cell counts either in the peripheral blood or in cerebrospinal fluid (CSF). Three-quarters of the patients were treated with a combination of albendazole and corticosteroids, resulting in significantly improved overall conditions. Twenty-two patients reported the consumption of raw or undercooked snails prior to the onset of the symptoms, and approximately 1.0% of the Pomacea canaliculata snails on sale were found to be infected with A. cantonensis. The snails were also found in certain habitats around Dali but no parasites were detected in these populations.

Conclusions/Significance

The import and sale of infected P. canaliculata is the likely trigger for this angiostrongyliasis outbreak. Awareness of angiostrongyliasis must be raised, and standardized diagnosis and treatment are needed in order to provide clinicians with a guide to address this disease. Health education campaigns could limit the risk, and a hospital-based surveillance system should be established in order to detect future outbreaks.  相似文献   
76.
圆形碘孢虫单链抗体库的筛选与阳性克隆特征分析   总被引:1,自引:0,他引:1  
噬菌体抗体库已成为单克隆抗体生成的重要技术之一。本文通过用圆形碘孢虫相关抗原对已构建的鼠源免疫噬菌体展示单链组合抗体文库进行生物淘选,并对几株相对亲和力较高的阳性单克隆序列特征、相对亲和力及热稳定性等进行了分析。ELISA、间接免疫荧光及免疫印迹等进行特征鉴定。结果表明,噬菌体抗体库技术对于分离抗圆形碘孢虫不同表位抗原是可行的,将为粘体动物的抗原物质及分布、寄生虫一宿主相互关系等研究提供丰富的抗体来源。  相似文献   
77.
波叶青牛胆胰蛋白酶抑制剂的纯化及其性质研究   总被引:4,自引:0,他引:4  
采用亲和层析及电泳制备等方法 ,从防已科植物波叶青牛胆 (Tinosporacrispa)根茎中分离到一种胰蛋白酶抑制剂TCTI。对其性质研究表明 :TCTI的相对分子量约为 10 0kD ,对牛胰蛋白酶的抑制常数Ki为 2 0 8× 10 7mol/L (BAPNA为底物时 ) ,摩尔抑制比为 1∶3 5 ,是一种抑制活力很强的竞争性抑制剂。TCTI具有很高的耐热性 ,在 10 0℃加热 60min ,仍保持 93%的抑制活力。另外 ,TCTI在低温容易结晶  相似文献   
78.
Electrophysiological characterization of T-type Ca2+ channel isoforms (Cav3.1, Cav3.2, and Cav3.3) has shown that all of the isoforms are low voltage-activated around resting membrane potential, but their current kinetics are distinctly different, with the activation and inactivation kinetics of the Cav3.1 and Cav3.2 channels being much faster than those of the Cav3.3 channel. We previously reported that multiple structural regions of the Cav3.3 T-type channel participate in determining its current kinetics. Here we have evaluated the relative contributions of individual cytoplasmic and trans-membrane regions to the current kinetics of the channel, by systematically replacing individual regions of Cav3.3 with the corresponding regions of Cav3.1. Introduction of the Cav3.1 III-IV loop into the Cav3.3 backbone accelerated both the activation and inactivation kinetics more prominently than any other intracellular loop or tail. Among the trans-membrane domains, introduction of the domain I of Cav3.1 into Cav3.3 accelerated both the activation and inactivation kinetics most effectively. These findings suggest that the current kinetics of the Cav3.3 channel are differentially controlled by several structural regions, among which the III-IV loop and domain I are the most prominent in governing both activation and inactivation kinetics.  相似文献   
79.
同色兜兰的组织培养与快速繁殖   总被引:4,自引:0,他引:4  
1植物名称同色兜兰[Paphiopedilum concolor(Bateman)Pfitz.]。 2材料类别种子。 3培养条件种子萌发培养基:(1)MS+100mL·L^-1香蕉汁;(2)1/2MS+100mL·L^-1香蕉汁。原球茎继代增殖培养基:(3)1/2MS+NAA0.2mg·L^-1(单位下同)+100mL·L^-1香蕉汁;(4)1/2MS+NAA0.4+100mL·L^-1香蕉汁;(5)1/2MS+6-BA0.5+NAA0.2+100mL·L^-1。  相似文献   
80.
对松林丁香S. pinetorum W. W. Sm.复合体内各学者发表的5个新种进行了分类修订。根据居群取样、性状分析和主坐标分析结果, 圆叶丁香S. wardii W. W. Sm.、S. mairei (H. Lév.) Rehder、S. rugulosa McKelvey和川西丁香S. chuanxiensis S. Z. Qu &; X. L. Chen被处理为松林丁香的异名, 其中S. mairei为新异名。此复合体只有一种, 即松林丁香。  相似文献   
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