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991.
992.
目的:探讨正常前列腺组织不同区带来源的前列腺间质细胞对前列腺癌细胞生长的影响及其作用机制。方法:以激素非依懒性前列腺癌细胞系DU145细胞为研究对象,取新鲜的正常前列腺外周带(PZ)和移行带(TZ)组织,提取间质细胞并体外培养。收集不同区带来源的间质细胞培养上清作为条件培养液培养DU145细胞,CCK8法测定肿瘤细胞的生长曲线,台盼蓝染色测定细胞数量及活力,细胞划痕实验测定细胞侵袭性,Western印迹法测定间质细胞对肿瘤细胞糖代谢关键酶的影响。结果:1PZ间质细胞的条件培养液能促进肿瘤细胞的生长,而TZ间质细胞的条件培养液抑制肿瘤细胞的生长;2PZ间质细胞的条件培养液明显增加肿瘤细胞糖代谢关键酶己糖激酶2(HK-2)、丙酮酸激酶2(PKM-2)、乳酸脱氢酶(LDHA)、丙酮酸脱氢酶(PDH)的表达,而TZ则抑制上述酶的表达。结论:前列腺不同来源的间质细胞对肿瘤细胞的生长影响不同,其机制可能与不同来源的间质细胞对糖酵解代谢的影响不同有关。 相似文献
993.
DJ Courtemanche WG Cannon RJM Courtemanche JS Williamson D Lyster 《CANADIAN JOURNAL OF PLASTIC SURGERY》2015,23(3):171-176
BACKGROUND:
Choke vessels dilate and contract to regulate blood flow between adjacent arterial angiosomes. In skin flap surgery, when arterial inflow to an angiosome is ligated, choke vessels allow blood supply from an adjacent angiosome. In muscle flap surgery, the vascular anatomy is analogous to skin flaps; however, while it is established that the choke vessels will fully dilate irreversibly after two to three days, no study has yet analyzed the acute changes in each vascular region immediately following ligation of one pedicle.OBJECTIVE:
To establish whether the choke vessels open or close immediately following ligation of a pedicle, and how this change affects blood flow in the adjacent proximal and distal vascular regions.METHODS:
Radioactive and fluorescent microspheres in a pig model were used to study the regional intramuscular blood flow in each anatomical zone of a rectus abdominis flap. Blood flow measurements for each zone were calculated relative to the entire muscle at preligation, ligation and various times (15 min to 90 min) postligation.RESULTS:
There was no statistically significant difference in blood flow across choke zones as a result of ligation. This signifies that the choke vessels do not significantly dilate to produce a statistically significant measureable change in blood flow.CONCLUSIONS:
Given these results and previous literature findings, the anatomical presence of choke vessels in a muscle is the strongest determining factor for acute flap viability in surgery. 相似文献994.
Gabriela Bastidas-Mora Sílvia Be Alba Navarro Eva Gine Dolors Costa Julio Delgado Tycho Baumann Laura Magnano Alfredo Rivas-Delgado Neus Villamor Dolors Colomer Mnica Lopez-Guerra María Rozman Olga Balagu Daniel Martínez Maria Joao Baptista Lourdes Escoda Miguel Alcoceba Margarita Blanes Fina Climent Elías Campo Andrew Wotherspoon Armando Lpez-Guillermo Estella Matutes 《British journal of haematology》2022,196(1):146-155
995.
Laetitia Lacoste-Collin Marion Castiella Xavier Franceries Emmanuelle Cassol Laure Vieillevigne Veronica Pereda Manuel Bardies Monique Courtade-Sa?di 《Dose-response》2015,13(4)
The study of cell survival following exposure to nonuniform radiation fields is taking on particular interest because of the increasing evidence of a nonlinear relationship at low doses. We conducted in vitro experiments using the MCF7 breast cancer cell line. A 2.4 × 2.4 cm2 square area of a T25 flask was irradiated by a Varian Novalis accelerator delivering 6 MV photons. Cell survival inside the irradiation field, in the dose gradient zone and in the peripheral zone, was determined using a clonogenic assay for different radiation doses at the isocenter. Increased cell survival was observed inside the irradiation area for doses of 2, 10, and 20 Gy when nonirradiated cells were present at the periphery, while the cells at the periphery showed decreased survival compared to controls. Increased survival was also observed at the edge of the dose gradient zone for cells receiving 0.02 to 0.01 Gy when compared with cells at the periphery of the same flask, whatever the isocenter dose. These data are the first to report cell survival in the dose gradient zone. Radiotherapists must be aware of this nonlinearity in dose response. 相似文献
996.
Coke is the only batch component that does not soften in blast furnace thermal conditions. It is especially important at the temperatures of the cohesive zone forming because coke layers are the only gas-permeable charge. The aim of the work described in this article is the identification of individual coke layers situation in the cohesive zone. Numerical calculations of the cohesive zone situation are based on the horizontal below burden probe measures, however, coke layers are calculated using analytical geometry. The results can be presented as a bitmap; the individual and total area of the coke layers passing gases through the cohesive zone is also calculated. This form of results allows for subjective but quick assessment of the blast furnace operation by its crew. 相似文献
997.
目的 探讨麝香保心丸对急性心肌梗死后室性心律失常的抑制作用及机制.方法 90只雄性急性心肌梗死大鼠随机分为麝香保心丸高、低剂量(45.0、22.5 mg/kg)组及模型组,每组30只,每组大鼠再均分为第1、2周末2个亚组,每组15只.另取20只大鼠作为假手术组,均分为第1、2周末2个亚组,每组10只.麝香保心丸组第1、2周末2个亚组分别于术后第2天起ig给药1、2周,假手术组和模型组给予等量生理盐水.第1、2周末时以程序电刺激诱发各组大鼠室性心律失常后,假手术组取位于左心室游离壁心肌组织,心肌梗死各组取位于左心室梗死边缘带心肌组织,检测白细胞介素-18(IL-18)表达.结果 第1、2周末时模型组大鼠梗死边缘带心肌组织中IL-18表达水平及室性心律失常诱发率均高于假手术组(P< 0.01).麝香保心丸低剂量组第2周末时梗死边缘带心肌组织中IL-18表达水平及室性心律失常诱发率显著低于模型组(P< 0.05),而第1周末时则无显著差异.麝香保心丸高剂量组第1、2周末梗死边缘带心肌组织中IL-18表达水平及室性心律失常诱发率显著低于模型组(P< 0.01).麝香保心丸高剂量组梗死边缘带心肌组织中IL-18表达水平及室性心律失常诱发率在第1周末(P< 0.01)、第2周末(P< 0.05)时均显著低于低剂量组.结论 麝香保心丸可通过抑制IL-18过度表达而降低急性心肌梗死后室性心律失常诱发率,其作用呈剂量相关性. 相似文献
998.
Radial glia inhibit peripheral glial infiltration into the spinal cord at motor exit point transition zones
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Cody J. Smith Kimberly Johnson Taylor G. Welsh Michael J. F. Barresi Sarah Kucenas 《Glia》2016,64(7):1138-1153
In the mature vertebrate nervous system, central and peripheral nervous system (CNS and PNS, respectively) GLIA myelinate distinct motor axon domains at the motor exit point transition zone (MEP TZ). How these cells preferentially associate with and myelinate discrete, non‐overlapping CNS versus PNS axonal segments, is unknown. Using in vivo imaging and genetic cell ablation in zebrafish, we demonstrate that radial glia restrict migration of PNS glia into the spinal cord during development. Prior to development of radial glial endfeet, peripheral cells freely migrate back and forth across the MEP TZ. However, upon maturation, peripherally located cells never enter the CNS. When we ablate radial glia, peripheral glia ectopically migrate into the spinal cord during developmental stages when they would normally be restricted. These findings demonstrate that radial glia contribute to both CNS and PNS development and control the unidirectional movement of glial cell types across the MEP TZ early in development. GLIA 2016. GLIA 2016;64:1138–1153 相似文献
999.
The maternal brain is remarkably plastic and exhibits multifaceted neural modifications. Neurogenesis has emerged as one of the mechanisms by which the maternal brain exhibits plasticity. This review highlights what is currently known about peripartum-associated changes in adult neurogenesis and the underlying hormonal mechanisms. We also consider the functional consequences of neurogenesis in the peripartum brain and extent to which this process may play a role in maternal care, cognitive function and postpartum mood. Finally, while most work investigating the effects of parenting on adult neurogenesis has focused on mothers, a few studies have examined fathers and these results are also discussed. 相似文献
1000.
库车前陆盆地是发育在南天山山前的中—新生代含盐前陆盆地,受造山作用、基底先存构造、盐湖分布等构造要素的影响,盆地具有明显的南北分带、东西分段变形特征,发育多种类型构造转换带。基于最新的2D、3D 地震资料及钻井、野外露头资料,分析总结了库车前陆冲断带的变形样式特征及构造转换方式。研究结果表明:(1)自南天山至盆地内部,库车前陆盆地表现为垂向分层变形特征,其中盐下冲断带主要集中于南天山至拜城凹陷,根据变形方式可以划分为垂向抬升断褶带、斜向冲断楔形带及近水平向挤压滑脱带3个变形带。(2)库车前陆盆地盐下冲断带可以分为乌什段、阿瓦特—博孜段、大北—克深段及克拉3段4个构造段,共发育走滑型、边缘型、生长型及混合型4种转换带类型。(3)总体上看,东西向一级转换带多为混合型,二级转换带多为边缘型及走滑型,三级转换带多为生长型,一级、二级、三级转换带分别控制了构造带、构造带内各构造段、局部构造的分布。 相似文献