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11.
采用粗纤维法、凯氏定氮法、斐林试剂法、索氏浸提法、干灰化法和重量法等多种化学分析方法对云南翠雀花的化学成分进行了分析.结果显示,云南翠雀花含有丰富的维生素、矿质元素以及异亮氨酸、蛋氨酸、赖氨酸等17种氨基酸,其中粗纤维、VB2和蛋氨酸含量尤为丰富,分别为32.83%、3.26 mg·g-1、3.27 mg· g-1.  相似文献   
12.
In neutrophils, adenosine triphosphate (ATP) release and autocrine purinergic signaling regulate coordinated cell motility during chemotaxis. Here, we studied whether similar mechanisms regulate the motility of breast cancer cells. While neutrophils and benign human mammary epithelial cells (HMEC) form a single leading edge, MDA-MB-231 breast cancer cells possess multiple leading edges enriched with A3 adenosine receptors. Compared to HMEC, MDA-MB-231 cells overexpress the ectonucleotidases ENPP1 and CD73, which convert extracellular ATP released by the cells to adenosine that stimulates A3 receptors and promotes cell migration with frequent directional changes. However, exogenous adenosine added to breast cancer cells or the A3 receptor agonist IB-MECA dose-dependently arrested cell motility by simultaneous stimulation of multiple leading edges, doubling cell surface areas and significantly reducing migration velocity by up to 75 %. We conclude that MDA-MB-231 cells, HMEC, and neutrophils differ in the purinergic signaling mechanisms that regulate their motility patterns and that the subcellular distribution of A3 adenosine receptors in MDA-MB-231 breast cancer cells contributes to dysfunctional cell motility. These findings imply that purinergic signaling mechanisms may be potential therapeutic targets to interfere with the motility of breast cancer cells in order to reduce the spread of cancer cells and the risk of metastasis.  相似文献   
13.
精准医疗是近年来医学的发展方向,精准医疗依赖于精准的诊断,而精准诊断则需要高质量病理学切片技术作为支撑。武汉大学人民医院病理科将精细化管理理念融入病理学技术质控和管理工作的每一环节,通过采用不同颜色包埋框对组织分类、时间梯度法调控出片时间、根据人员资质及医疗风险对病理学技术人员分级授权、专人专机负责制、信息化管理、PDCA循环法持续改进等管理措施为精准病理学诊断打好基础,大大提高了诊断准确率和及时率,为临床病理学诊断提供了可靠的技术支撑。  相似文献   
14.
目的探讨原发性乳腺弥漫性大B细胞淋巴瘤(primary breast diffuse large B-cell lymphoma,PB-DLBCL)的临床病理学特点、诊断及鉴别诊断、治疗及预后。方法采用HE染色和免疫组织化学SP法分析5例PB-DLBCL患者的临床表现、病理学及免疫表型特征,并复习相关文献。结果 5例均为女性患者,发病年龄48~70岁,中位年龄59.2岁,均为单侧乳腺肿块,其中左乳3例,右乳2例。镜下见乳腺正常结构被破坏,成片的中等偏大的肿瘤细胞弥漫浸润乳腺小叶、导管周围、间质及周围脂肪组织。根据免疫组织化学表型,4例为非生发中心型,1例为生发中心型;Ki67增殖指数为60%~90%;根据 Ann Arbor 分期标准,5例均为II E期。病例随访时间截止至2018年6月,随访期内,有2例复发,分别于7和19个月后死亡;2例健在,分别已存活12和72个月;另外一例失访。结论 PB-DLBCL是一种少见的恶性淋巴瘤,临床表现为单侧乳腺无痛性包块进行性增大,以右侧多见。确诊主要依靠病理活检及免疫表型,免疫表型以非生发中心为主,以化疗联合放疗等综合治疗方案为宜。  相似文献   
15.
为了解国产绿‘奇楠’沉香的化学成分,采用色谱和波谱方法从其乙醚和乙醇提取物中分离鉴定了7个化合物,分别鉴定为顺式-7-羟基菖蒲烯(1),(5R,6R,7S,8R)-2-(苯乙基)-6,7,8-三羟基-5,6,7,8-四氢-5-[2-(2-苯乙基)色酮基-6-氧代]色酮(2), 1-羟基-1,5-二苯基戊-3-酮(3),丁香树脂酚葡萄糖苷(4),(3β)-齐墩果-12-烯-3,23-二醇(5),β-谷甾醇(6)和棕榈酸-α-单甘油酯(7)。化合物1、3~5和7均为首次从沉香中分离得到,其中化合物1表现出非常甜的芳香气味。乙酰胆碱酯酶体外抑制活性测试结果表明,50μmol L~(–1)的化合物1对乙酰胆碱酯酶抑制率为(49.9±1.4)%。  相似文献   
16.
Dopamine D1 receptors play an important role in movement, reward, and learning and are implicated in a number of neurological and psychiatric disorders. These receptors are concentrated in dendritic spines of neurons, including the spine head and the postsynaptic density. D1 within spines is thought to modulate the local channels and receptors to control the excitability and synaptic properties of spines. The molecular mechanisms mediating D1 trafficking, anchorage, and function in spines remain elusive. Here we show that the synaptic scaffolding protein PSD-95 thought to play a role in stabilizing glutamate receptors in the postsynaptic density, interacts with D1 and regulates its trafficking and function. Interestingly, the D1-PSD-95 interaction does not require the well characterized domains of PSD-95 but is mediated by the carboxyl-terminal tail of D1 and the NH(2) terminus of PSD-95, a region that is recognized only recently to participate in protein-protein interaction. Co-expression of PSD-95 with D1 in mammalian cells inhibits the D1-mediated cAMP accumulation without altering the total expression level or the agonist binding properties of the receptor. The diminished D1 signaling is mediated by reduced D1 expression at the cell surface as a consequence of an enhanced constitutive, dynamin-dependent endocytosis. In addition, genetically engineered mice lacking PSD-95 show a heightened behavioral response to either a D1 agonist or the psychostimulant amphetamine. These studies demonstrate a role for a glutamatergic scaffold in dopamine receptor signaling and trafficking and identify a new potential target for the modulation of abnormal dopaminergic function.  相似文献   
17.
该文系统回顾了华南国家植物园近百年来几个关键时期的历史发展、主要成就和社会贡献,从国家、中国科学院、地方政府三个层面分析了华南国家植物园率先设立的缘由,展望了华南国家植物园的未来发展前景,提出了我国国家植物园体系建设的思考和建议。  相似文献   
18.
SWEET(sugar will eventually be exported transporter)家族是一种新型的糖转运体,该家族基因在碳水化合物运输、发育、环境适应性和寄主-病原相互作用等多个过程中发挥着重要作用.为更好地了解南瓜发育的分子机理,该研究基于已知的南瓜基因组数据库,利用生物信息学方法对中国南瓜SW...  相似文献   
19.
Two representatives of a new class of cationic lipids were found to have high pore-forming activity in planar bilayer membranes. These molecules, called BHHD-TADC and BHTD-TADC, have qualitatively similar effects on phospholipid membranes. Addition of 2.5-5 micro M of either of them to the membrane bathing solutions resulted in formation of long-lived anion-selective pores with conductance in the range 0.1-2 nS in 0.1 M KCl. Pore formation was found to be dependent on the potential applied to the membrane. When negative potential was applied to membrane at the side of addition, the rate of pore formation was much lower compared to when the positive potential was applied. Dependence of pore formation on compound concentration was highly nonlinear, indicating that this process requires assembly of molecules in the membrane. Addition of any of these compounds on both sides of the membrane increased the efficiency of pore formation by one to two orders of magnitude. Pore formation was strongly pH dependent. Although pores were formed with high efficiency at pH 6.5, only occasional fluctuations of membrane conductance were observed at pH 7.5. Possible mechanisms of new compounds biological activity are discussed.  相似文献   
20.
兰花蕉花部维管束系统的解剖学研究   总被引:10,自引:5,他引:5  
兰花蕉花梗的维管束分散排列.子房基部的维管束排成两部分,外方为一轮大维管束环,中央为分散排列的小维管束区。前者的纸管束进入子房壁,后者进入子房的中轴,形成股座纸管束;及至延长都以后,股座维管束逐渐消失.子房壁上的维管束较易识别的有心皮背束、心皮背束伴束和隔膜束.三束心皮背束经延长部最终进入花柱和柱头.心皮背束指心皮背束务与其紧靠的大维管束,三枚心皮背束伴束最终分别进入三枚外轮雄蓝.三枚隔膜束中远轴面的两枚分别进入两校内轮雄蕊,而近轴面的一枚伴随着第六枚雄蓝的缺失最后进入唇瓣中央.子房壁其余的维管束进入延长部后,先向外分出一轮纸管束进入花幕,余下的中央部分排成一轮心形的线管来环.该环远轴面的维管束分为两半分别进入两枚侧生花瓣;近轴面即心形凹陷一侧初为两轮即外轮大的维管束与内轮小的维管束,后排成一轮并与近轴面的隔膜束一同进入唇瓣.兰花蕉的唇瓣既为花瓣成员,又含一枚缺失的雄蓝维管束,与姜目已报道的只来自退化雄蕊的竹芋科的兜状结构和美人蕉科、姜科、闭鞘姜科的唇瓣有明显区别.在旅人蕉科尚未有研究资料的情况下,作者根据已有资料,对姜目雄蕊维管束系统来源和结构进行比较,初步认为在姜目的系统演化上,兰花蕉科与芭蕉料更近.  相似文献   
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