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排序方式: 共有122条查询结果,搜索用时 171 毫秒
71.
肝素作为传统抗凝剂,常用来治疗癌症患者静脉血栓。临床和实验数据证实,肝素具有抗肿瘤活性。同时也有大量研究发现,肝素有抗肿瘤转移的作用。肝素可以通过各种机制抑制肿瘤转移,包括抑制细胞间的相互作用;抑制肝素酶的表达;调节各种生长因子以及调节机体凝血功能等。选凝素(seletin)是介导肿瘤转移初始阶段的重要因子,而肝素能够抑制选凝素介导的的肿瘤细胞与白细胞、血小板及内皮细胞的相互作用,从而达到抗转移的效果。本文综述了肝素抑制选凝素介导的肿瘤转移的作用机制,为肝素在抗肿瘤转移方面的临床应用提供参考。 相似文献
72.
73.
Ming-Feng Yang Jie Song Bao-Shan Wang Key Laboratory of Plant Stress Research College of Life Sciences Sh ong Normal University Jinan China Institute of Botany the Chinese Academy of Sciences Beijing China 《Acta Botanica Sinica》2010,(3)
Suaeda salsa L. is a halophytic species that is well adapted to high salinity. In order to understand its salt tolerance mechanism, we examined the growth and vacuolar H+-ATPase (V-ATPase) response to NaCl within the shoots and roots. The growth of shoots, but not roots, was dramatically stimulated by NaCl. Cl? and Na+ were mainly accumulated in shoots. V-ATPase activity was significantly increased by NaCl in roots and especially in shoots. Interestingly, antisera ATP95 and ATP88b detected three V1 subunits... 相似文献
74.
移植胎鼠间充质干细胞的抗衰老作用 总被引:4,自引:0,他引:4
本文旨在研究BALB/c小鼠胎鼠源干细胞同种异体移植的抗衰老作用。采用无菌剖宫产取胎鼠,密度梯度离心法分离干细胞,贴壁培养法纯化扩增间充质干细胞,连续3次尾静脉注射P1代细胞植入15月龄雌性BALB/c小鼠体内。超声检查小鼠心脏,检查血清总超氧化物歧化酶活力、丙二醛含量、谷胱甘肽过氧化物酶活力,各器官做解剖学检查以及组织学衰老程度比较、评分。结果显示,Y染色体原位杂交实验检测到移植后干细胞长期存活,移植后移植组小鼠存活日期明显长于对照组,移植3个月后评价心功能的各指标,心脏质量指数、脾脏质量指数,心脏、肾脏、肺脏、皮肤、结肠等器官组织学衰老程度评分结果以及血液生化指标,皆优于对照组(均P0.05)。以上结果提示,移植小鼠胎鼠源干细胞能有效地延缓小鼠衰老进程。 相似文献
75.
Zhichao Tang Sana Akhter Ankita Ramprasad Xiao Wang Mikhail Reibarkh Jinan Wang Sadikshya Aryal Srinivas S Thota Junxing Zhao Justin T Douglas Philip Gao Erik D Holmstrom Yinglong Miao Jingxin Wang 《Nucleic acids research》2021,49(14):7870
Risdiplam is the first approved small-molecule splicing modulator for the treatment of spinal muscular atrophy (SMA). Previous studies demonstrated that risdiplam analogues have two separate binding sites in exon 7 of the SMN2 pre-mRNA: (i) the 5′-splice site and (ii) an upstream purine (GA)-rich binding site. Importantly, the sequence of this GA-rich binding site significantly enhanced the potency of risdiplam analogues. In this report, we unambiguously determined that a known risdiplam analogue, SMN-C2, binds to single-stranded GA-rich RNA in a sequence-specific manner. The minimum required binding sequence for SMN-C2 was identified as GAAGGAAGG. We performed all-atom simulations using a robust Gaussian accelerated molecular dynamics (GaMD) method, which captured spontaneous binding of a risdiplam analogue to the target nucleic acids. We uncovered, for the first time, a ligand-binding pocket formed by two sequential GAAG loop-like structures. The simulation findings were highly consistent with experimental data obtained from saturation transfer difference (STD) NMR and structure-affinity-relationship studies of the risdiplam analogues. Together, these studies illuminate us to understand the molecular basis of single-stranded purine-rich RNA recognition by small-molecule splicing modulators with an unprecedented binding mode. 相似文献
76.
Yang J Wang J Zhu S Chen X Wu H Yang D Zhang J 《Molecular and cellular biochemistry》2008,310(1-2):215-226
C-reactive protein (CRP) is an important predictive factor for cardiac disorders including acute myocardial infarction. Therapeutic
inhibition of CRP has been shown to be a promising new approach to cardioprotection in acute myocardial infarction in rat
models, but the direct effects of CRP on cardiac myocytes are poorly defined. In this study, we investigated the effects of
CRP on cardiac myocytes and its molecular mechanism involved. Neonatal rat cardiac myocytes were exposed to hypoxia for 8 h.
Hypoxia induced myocyte apoptosis under serum-deprived conditions, which was accompanied by cytochrome c release from mitochondria into cytosol, as well as activation of Caspase-9, Caspase-3. Hypoxia also increased Bax and decreased
Bcl-2 mRNA and protein expression, thereby significantly increasing Bax/Bcl-2 ratio. Cotreatment of CRP (100 μg/ml) under
hypoxia significantly increased the percentage of apoptotic myocytes, translocation of cytochrome c, Bax/Bcl-2 ratio, and the activity of Caspase-9 and Caspase-3. However, no effects were observed on myocyte apoptosis when
cotreatment of CRP under normoxia. Furthermore, Bcl-2 overexpression significantly improved cellular viability through inhibition
of hypoxia or cotreatment with CRP induced Bax/Bcl-2 ratio changes and cytochrome c release from mitochondria to cytosol, and significantly blocked the activity of Caspase-9 and Caspase-3. The present study
demonstrates that CRP could enhance apoptosis in hypoxia-stimulated myocytes through the mitochondrion-dependent pathway but
CRP alone has no effects on neonatal rat cardiac myocytes under normoxia. Bcl-2 overexpression might prevent CRP-induced apoptosis
by inhibiting cytochrome c release from the mitochondria and block activation of Caspase-9 and Caspase-3.
Jin Yang and Junhong Wang contributed equally to this work. 相似文献
77.
离子交换色谱法对大肠杆菌表达的人重组骨形态发生蛋白-7的纯化 总被引:1,自引:0,他引:1
重组大肠杆菌高量表达重组人骨形态发生蛋白-7(rhBMP-7),每升培养液约得到湿菌体3g,其中目的蛋白约占菌体总蛋白量的40%。裂解离心,用低浓度变性剂洗涤初步纯化包涵体,上清中无目的蛋白损失;将包涵体溶解于高浓度变性剂溶液中,目的蛋白纯度提高到60%;然后在不同条件下用离子交换色谱法对变性状态下的蛋白质进行纯化,绝大部分杂蛋白被除去,目的蛋白纯度达95%以上;改变条件,可以减少rhBMP-7损失;用Western blot对目的蛋白进行特异性鉴定。 相似文献
78.
因子Xa抑制剂研究进展 总被引:2,自引:0,他引:2
因子X位于内外源性凝血途径的交汇处,其活性形式因子Xa(FXa)与因子Va、Ca^2 、PF3一起激活凝血酶原,产生凝血酶,触发凝血级连发应的发生。由于其在凝血途径中的重要位置,FXa抑制剂成为抗凝治疗新药开发中很有吸引力的靶位点。 相似文献
79.
带有pBV221-hBMP-7的E.coli表达得到的rhBMP-7以不溶的包涵体形式存在,用高浓度的变性利溶解后,经过DEAE-FF纯化,得到高纯度的目的蛋白,达95%以上。分别用尿素浓度梯度降低法、添加促复性剂及人工分子伴侣法对蛋白质进行复性,并通过不同方法对复性结果进行比较。Western blot中辉度扫描结果显示,GSH/GSSG法样品二聚体/单体比例为79.5/20.5,尿素浓度梯度降低法二聚体/单体比例为73.6/26.4,表明GSH/GSSG法复性样品溶液上清中含较高比例的蛋白质二聚体。根据不同复性样品对NIH3T3细胞ALP活性影响大小的比较结果,氧化还原剂最有助于二聚体的形成,蛋白质活性最高。 相似文献
80.