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61.
Diallyl disulfide (DADS) is a major constituent of garlic. Previously, we found that DADS both inhibited proliferation in human gastric cancer cells in vitro and in vivo, and induced G2/M arrest. In this study, we investigated whether this differentiation effect was induced by DADS in human gastric cancer MGC803 cells, and whether it was related to an alteration in ERK activity. The results showed that the growth of MGC803 cells was inhibited by DADS. Cells treated with DADS displayed a lower nucleocytoplasmic ratio and tended to form gland and intercellular conjunction structures. The ConA-mediated cell agglutination ratio and cells’ ALP specific activity decreased. In MGC803 cells, dye transfer was limited to a few cells neighbouring the dye-injected cell and to a depth of 1–2 layers beneath the scrape site. However, after treatment with DADS, the LY (Lucifer Yellow) was transferred to several cells immediately neighbouring the microinjected cell and to a depth of 2–4 cell layers from the scrape site. This indicated that DADS induced differentiation in MGC803 cells. Western blot analysis revealed that although DADS did not influence the quantity of ERK1/2 protein expressed, it did decrease its phosphorylation in a concentration-dependent manner, compared with the controls. At 30 mg·L−1, DADS inhibited the activation of ERK1/2 in 15–30 min. These results suggested that the DADS-induced differentiation of MGC803 cells involved an alteration of the ERK1/2 signaling pathway.  相似文献   
62.
The development of digestive organs in vertebrates involves active epithelial-mesenchymal interactions. In the chicken proventriculus (glandular stomach), the morphogenesis and cytodifferentiation of the epithelium are controlled by the inductive signaling factors that are secreted from the underlying mesenchyme. Previous studies have shown that Fgf10 is expressed in the developing chicken proventricular mesenchyme, whereas its receptors are present in the epithelium. In our present study, we show that FGF10 is an early mesenchymal signal that is critically associated with the developmental processes in the proventricular epithelium. Furthermore, virus-mediated Fgf10 overexpression in ovo results in a hypermorphic epithelial structure and an increase in epithelial cell number. In contrast, the overexpression of a secreted FGFR2b (sFGFR2b), an FGF10 antagonist, blocks cell proliferation and gland formation in the proventricular epithelium in ovo. This downregulation of proliferative activity was subsequently found to retard gland formation and also to delay differentiation of the epithelium. These results demonstrate that FGF10 signaling, mediated by FGFR1b and/or FGFR2b, is required for proliferation and gland formation in the epithelium in the developing chick embryo.  相似文献   
63.
B. Vicandi, J.A. Jiménez‐Heffernan, P. López‐Ferrer, P. González‐Peramato, M. Patrón and J.M. Viguer
Fine needle aspiration cytology of basal cell adenoma of the salivary gland: a cytohistological correlation study of 35 cases Objective: In order to evaluate the possibility of a specific cytological recognition of basal cell adenoma (BCA) we reviewed our experience with 35 histologically proven cases. Few series describing cytological features of BCA are available and diagnostic cytological criteria are not well established. Methods: This study was based on 41 cytology samples from 35 patients with BCA. Thirty‐five aspiration procedures were performed pre‐operatively and six on tumour recurrence. Nineteen of the 35 patients were men and 16 women. The mean age at diagnosis was 55 years old (range 24–92). The series includes one non‐representative case. Except for one tumour located in the upper lip, all of them involved the parotid gland. Results: Aspirates were cellular, showing groups with dense, homogeneous metachromatic stroma and single cells. Relevant features were the trident‐like configuration of groups, intimate relationship between neoplastic cells and stroma and cellular polymorphism. In approximately half of the cases a precise diagnosis was given. Most of the remaining tumours were diagnosed as benign but they were difficult to differentiate from pleomorphic adenoma. Regarding malignancy, there were two misdiagnoses of acinic cell carcinoma, due to high epithelial cellularity along with scarcity of stroma, and one case was considered to be suspicious of malignancy. Conclusion: BCA shows characteristic cytological features that allow a precise diagnosis. The main differential diagnosis is epithelial‐rich pleomorphic adenoma, while acinic cell carcinoma is a potential false positive.  相似文献   
64.
目的:评估胃癌根治术同时性射频消融治疗在治疗胃癌肝转移的临床意义。方法:收集2008年1月至2010年12月19例胃癌肝转移患者,合计转移灶33个,转移灶小于4厘米,且合计不超过4个转移灶。射频消融治疗在术中超声引导下完成。Kap-lan—Meier法分析无病生存期,无肝转移生存期及总生存期。对临床病理学因子及肝转移相关因子采用Log-rank法Cox风险比例模型解析。结果:中位无病生存、无肝转移生存及总生存期为355,394及488天。有3例患者获得长期的无复发生存。单因素分析显示,较早的T分期、N分期,较少的转移灶数量,较小的转移灶直径与良好的预后相关。多因素分析提示,病灶数量与病灶直径为独立预后因子。结论:肝转移射频消融治疗安全性好,对单发的小于4cm转移灶,以及多发病灶合计直径小于4cm者射频消融治疗较为适用,可有显著生存获益。部分患者可迭临床治愈。对于胃癌肝转移的合适病例,射频消融治疗值得推广。  相似文献   
65.
罗飞  李志英 《生命科学》2012,(4):346-349
Th17细胞是近年发现的一种新型CD4^+效应性T细胞,以其特异性的分泌IL-17而命名。介导免疫耐受的Treg细胞和介导炎症反应的Th17细胞间功能和分化过程相互对抗,在正常状态下,两者保持平衡,但机体发生功能异常时常表现出Treg/Th17失衡,引起炎性反应、自身免疫性疾病、移植物抗宿主病等的发生和发展,并决定疾病的转归和预后,在肿瘤免疫中亦发挥了重要作用。该文就Treg/Th17失衡在肿瘤,尤其是子宫颈癌发生发展中的作用进行综述。  相似文献   
66.
目的:探讨肥大细胞(mast cell,MC)及类胰蛋白酶(tryptase)与甲状腺肿瘤微血管密度(microvessel density,MVD)的相关性及其对甲状腺癌发生发展的影响。方法:采用甲苯胺蓝组织化学染色和PV免疫组织化学染色对116例甲状腺癌、56例甲状腺腺瘤和10例正常甲状腺组织中MC和tryptase及其CD31的表达进行了检测;对MC和tryptase与MVD的关系进行了统计学分析。结果:甲状腺肿瘤中MC的数量和tryptase阳性表达高于正常甲状腺,而且与肿瘤的类型有关(P<0.01);Spearman等级相关分析显示各组甲状腺组织MC数量和tryptase表达与MVD呈正相关(r=0.900,r=0.636,P<0.05)。结论:MC及其分泌的tryptase有促进血管新生的作用,因而可促进甲状腺肿瘤的浸润和转移。  相似文献   
67.
目的:研究替吉奥联合顺铂治疗晚期胃癌的疗效和安全性.方法:42例晚期胃腺癌患者随机分为观察组(21例)与对照组(21例)两组,观察组采用替吉奥联合顺铂,对照组采用卡培他滨联合顺铂.结果:两组患者疗效间差异无统计学意义(P>0.05).两组的不良反应主要为骨髓抑制、消化道反应和乏力,观察组Ⅲ~Ⅳ度血小板减少发生率显著低于对照组(P<0.05),Ⅲ~Ⅳ度手足综合征的发生率亦显著低于对照组(P<0.05).结论:替吉奥联合顺铂治疗晚期胃癌疗效与卡培他滨联合顺铂相当,但其患者耐受性更好,值得临床进一步研究推广使用.  相似文献   
68.
在有丝分裂过程中BUBR1监视微管与着丝点的结合,是保证染色体均等分离的重要分子机制之一.BUBIB变异家谱研究及其敲除模型的研究表明,BUBR1缺陷与染色体不稳定性及肿瘤的发生直接相关.近来在数种人类肿瘤,对BUBR1蛋白过度表达有所报道.但在直结肠癌,BUBR1的过度表达是否与染色体不稳定性的发生有关目前仍无定论.在人类结直肠癌的遗传不稳定性主要表现为两种类型,染色体不稳定性及微卫星不稳定性,它们提示了两条独立的肿瘤发生路径.一般认为不存在高频度微卫星不稳定性表型的肿瘤通过染色体不稳定途径癌变.P53蛋白通过多种机制对维护遗传稳定性起到重要的作用,TP53基因突变经常与染色体不稳定现象并存.DNA倍体情况也是染色体不稳定研究不可缺少的指标.本研究采用免疫组织化学法检测了一组93例进展期散发结直肠癌BUBR1蛋白的表达情况,直接测序法检测TP53变异.高分辨率荧光标记微卫星不稳定检测技术检测微卫星状态,固相激光扫描细胞仪技术检测DNA倍体情况.我们分析了BUBR1表达与三种反映遗传背景的因子的关系.BUBR1蛋白过度表达在人结直肠癌较为常见.在非高频度微卫星不稳定的结直肠癌,BUBR1蛋白过度表达率明显为高(P<0.01),在TP53基因突变的病例其过度表达率亦较高(P<0.05).BUBR1蛋白的过度表达与DNA异倍体无统计学相关,但DNA异倍体病例的BuBRl过度表达有偏高倾向.BuBRl表达情况与常用的临床病理学指标无统计学相关.BuBRl过度表达同微卫星状态及TP53突变的关系明确的提示,在人类散发结直肠癌,BUBR1蛋白过度表达与染色体不稳定状态有关.BUBR1过度表达作为一种常见的分子异常,对于肿瘤的早诊预防提供新的标志物.并可能成为治疗的新靶点.  相似文献   
69.
This study examines seasonal and spatial patterns in the diet composition, stomach fullness and condition of a landlocked population of brown trout (2.5–61.3 cm) in the lake-fed River Laxá in NE-Iceland. The stomach contents consisted predominantly of benthic invertebrates, such as blackfly larvae Simulium vittatum (58%), chironomids (24%) and the freshwater snail Radix peregra (7%). The seasonal and spatial patterns of S. vittatum in the stomach contents were consistent with published studies on the life cycle and production of S. vittatum in the River Laxá. Close to the Lake Myvatn outlet (0–16 km), S. vittatum constituted 63% of the stomach content volume, and exhibited two peaks (i.e., generations) in its seasonal contribution to the stomach contents, whereas further downstream (16–35 km) S. vittatum constituted 45% of the volume and showed only clear evidence of one generation. Seasonal fluctuations in S. vittatum availability appear to affect the stomach fullness and the condition factor of the trout, especially close to the lake outlet where the fluctuations are pronounced.  相似文献   
70.
人胎胃壁内NOS阳性神经元发育的研究   总被引:2,自引:0,他引:2  
研究用NADPH-d组织化学法对第3个月胎龄至足月人胎胃壁内NOS阳性神经元的分化,迁移和生长发育进行了观察。结果表明:第5个月龄时,肌层神经节处的圆形细胞出现一氧化氮合酶(nitric oxide synthase,NOS)阳性反应。第6个月龄时,NOS阳性细胞分化演变成NOS阳性神经细胞,细胞呈圆形或椭圆形,核大,细胞质极少,由细胞发出短小的6个月龄时,NOS阳性细胞分化演变成NOS阳性神经细胞,细胞呈圆形或椭圆形,核大,细胞质极少,由细胞发出短小的突起,有部分NOS阳性细胞分化演变成梭形的NOS阳性神经细胞,呈条索状排列和粘膜下层延伸,吸的到达粘膜层,在粘膜层形成网状细胞,第7个月龄时,神经元细胞明显增大,细胞质增多,染色加深,在肌层形成神经节,神经节细胞突起投射到整个肌层,第8-10个月龄时,肌层和粘膜下层神经元日趋成熟,细胞质增多,染色强度加深,肌层神经纤维分布密度增加,大多数神经纤维增粗,有的呈弹簧样弯曲,其走向与肌纤维长轴平行。结果提示;人胎胃壁内NOS阳性神经元来源于胚胎早期肌层神经节处的圆形细胞,通过分化,生长发育形成成熟的NOS阳性神经元。  相似文献   
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