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991.
原位缺口平移测定鼻咽癌细胞的放射敏感性   总被引:1,自引:0,他引:1       下载免费PDF全文
报道了以原位缺口平移(ISNT)技术研究鼻咽癌细胞株CNE、CNE-2Z对γ射线的放射效应,以及用存活曲线验证ISNT的可靠性。结果表明,在0~8Gy剂量之间,CNE及CNE-2Z的脱氧三磷酸核苷(dNTP)掺入率与照射剂量间呈良好量效关系;CNE-2Z的放射敏感性高于CNE。相关分析表明,cNE及CNE-2Z细胞ISNT的dNTP掺入率与存活分数之间均有良好的相关关系。表明ISNT可以较好地反映射线对肿瘤细胞的损伤效应,可替代复杂的集落形成试验,可望成为评价肿瘤细胞放射敏感性的一个重要指标。  相似文献   
992.
Fluorine-18 labeled 2beta-carbomethoxy-3beta-(4-chlorophenyl)-8-(2-fluoroethyl)nort ropane (FECNT) was synthesized in the development of a dopamine transporter (DAT) imaging ligand for positron emission tomography (PET). The methods of radiolabeling and ligand synthesis of FECNT, and the results of the in vitro characterization and in vivo tissue distribution in rats and in vivo PET imaging in rhesus monkeys of [18F]FECNT are described. Fluorine-18 was introduced into 2beta-carbomethoxy-3beta-(4-chlorophenyl)-8-(2-fluoroethyl)nort ropane (4) by preparation of 1-[18F]fluoro-2-tosyloxyethane (2) followed by alkylation of 2beta-carbomethoxy-3beta-(4-chlorophenyl)nortropane (3) in 21% radiochemical yield (decay corrected to end of bombardment [EOB]). Competition binding in cells stably expressing the transfected human DAT serotonin transporter (SERT) and norepinephrine transporter (NET) labeled by [3H]WIN 35428, [3H]citalopram, and [3H]nisoxetine, respectively, indicated the following order of DAT affinity: GBR 12909 > CIT > 2beta-carbomethoxy-3beta-(4-chlorophenyl)-8-(3-fluoropropyl) nortropane (FPCT) > FECNT. The affinity of FECNT for SERT and NET was 25- and 156-fold lower, respectively, than for DAT. Blocking studies were performed in rats with a series of transporter-specific agents and demonstrated that the brain uptake of [18F]FECNT was selective and specific for DAT-rich regions. PET brain imaging studies in monkeys demonstrated high [18F]FECNT uptake in the caudate and putamen that resulted in caudate-to-cerebellum and putamen-to-cerebellum ratios of 10.5 at 60 min. [18F]FECNT uptake in the caudate/putamen peaked in less than 75 min and exhibited higher caudate- and putamen-to-cerebellum ratios at transient equilibrium than reported for 11C-WIN 35,428, [11C]CIT/RTI-55, or [18F]beta-CIT-FP. Analysis of monkey arterial plasma samples using high performance liquid chromatography determined that there was no detectable formation of lipophilic radiolabeled metabolites capable of entering the brain. In equilibrium displacement experiments with CIT in rhesus monkeys, radioactivity in the putamen was displaced with an average half-time of 10.2 min. These results indicate that [18F]FECNT is a radioligand that is superior to 11C-WIN 35,428, [11C]CIT/RTI-55, [18F]beta-CIT-FP, and [18F]FPCT for mapping brain DAT in humans using PET.  相似文献   
993.
目的 观察肝卵圆细胞(hepatic oval cell,HOC)对肝纤维化(hepatofibrosis,HF)大鼠肝组织中细胞外信号调节蛋白(extracellular regulated protein kinases,ERK)和丝裂原激活蛋白激酶(mitogen activated protein kinase,P38MAPK)信号通路蛋白的影响.方法 SD大鼠以高脂低蛋白饲养、饮用10%乙醇,皮下注射40%CCl4,隔4 d注射一次,连续8周制备HF模型.HF大鼠采用胶原酶原位灌注法分离,percall纯化原代HOC.HOC悬液0.5 ml(1×109个细胞)经门静脉植入8周HF大鼠的肝脏内,分别于8、15、30d处死大鼠,HE和Masson染色观察HF病理组织学变化,Western blot 法检测肝组织ERK与P38MAPK信号通路蛋白的表达,同时检测ALB、FGF-3、c-kit、HNF-1α、PCNA表达.结果 病理组织学显示,HOC处理组大鼠HF被部分逆转,肝组织胶原纤维增生程度明显减轻,肝组织Ras、ERK、p-ERK、c-fos、c-jun、STAT3、ALB、FGF-3、PCNA蛋白表达显著下降(分别F=91.88,36.28,54.66,93.07,64.76,58.49,52.63,20.45,27.03,均P<0.05),而HNF-α1和c-kit表达上调(分别F=18.63,25.99,均P<0.05).结论 HOC抑制HF活化的ERK信号通路而改善肝纤维化程度,在HOC存在条件下p-P38并不激活c-fos、c-jun、STAT3、5表达,c-kit和HNF-1α表达增加,而肝组织结构损害程度明显减轻,肝纤维化程度明显改善.
Abstract:
Objective To observe the influence of hepatic oval cell (HOC) on the expression ERK and P38MAPK signaling pathway protein in liver tissue of murine experimental hepatofibrosis (HF).Method SD rats were fed with 10% ethanol and food with high-fat and low-protein, and were injected subcutaneously with carbontetrachloride once every four days for 8 weeks to establish hepatic fibrosis. HOGs were isolated from male HF rats by collagenase porfusion of the liver. HF rats at 8th week were transplanted with 0. 5 ml HOC suspension medium at a density of 1 × 109 cell /ml via portal vein, and the rats were sacrificed at 8th, 15th, 30th day respectively. Histopathologic changes of liver tissues were observed by HE and Masson. The expression of ERK and P38MAPK signaling pathway protein were determined by Western blotting. Result Hepatofibrosis was reversed and the degree of hyperplasia fibrilcollagen in hepatic fibrosis rats decreased significantly by HOC transplantion. HOC down-regulated the protein expression of Ras, ERK,p-ERK, c-fos, c-jun, STAT3, ALB, FGF-3, PCNA ( F = 91.88,36.28,54.66,93.07,64.76,58.49,52.63,20.45 ,27.03, all P < 0.05 ), up-regulated the protein expression level of HNF-α1, PDGF-Rβ significantly in liver tissues(F = 18.63,25.99,P <0.05). Conclusions HOC improves the degree of hepatofibrosis through inhibiting hyperplasia of collagen fibril in liver tissue of hepatofibrosis rats. With the presence of HOC the expression of c-fos,c-jun,STAT3,5 was not activated by p-P38MAPK. The expression of c-kit and HNF-1α increased and that liver tissue injury alleviated, and hepatofibrosis was improved.  相似文献   
994.
Ruan L  Zhong WD  Li ZM  Hua X 《中华男科学杂志》2011,17(10):880-883
目的:研究维生素D受体(VDR)基因启动子FokⅠ多态性与良性前列腺增生(BPH)合并组织学前列腺炎的关系。方法:应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)对79例BPH合并前列腺炎患者(炎症组)及81例单纯BPH患者(对照组)的外周血进行FokⅠ多态性检测,分析两组间基因型和等位基因的频率分布。结果:炎症组基因型分布FF:27%(21/79),Ff:30%(24/79),ff:43%(34/79);对照组FF:33%(27/81),Ff:36%(29/81),ff:31%(25/81),其中ff基因型分布在两组中差异有统计学意义(P〈0.05)。炎症组与对照组等位基因F分布频率分别为42%(142/338)和51%(159/312),P〉0.05,f分别为58%(196/338)和49%(153/312),P〈0.05。结论:VDR基因FokⅠ多态性与BPH中组织学前列腺炎发生有一定关系。  相似文献   
995.
目的探讨微波消融治疗小肾癌的合理性、安全性、临床疗效。方法2005年7月至2008年12月,我们对15例小肾癌患者进行了微波消融治疗,术后病检均证实为肾细胞癌。其中男9例,女6例;中位年龄58.2岁。15例患者中2例为孤立肾,1例为双侧肾肿瘤,6例合并肾功能不全,2例合并肾病综合征,1例合并对侧肾结石,3例心脏功能及全身情况差。结果4例为开放微波消融,11例为腹腔镜下微波消融,平均接受1~3个点的微波消融(50W,每个点5~8min)。开放手术时间平均72min,腹腔镜手术时间平均65min,出血量均较少。2例患者术后出现漏尿,放置双J管1个月后无漏尿,其余患者无手术相关并发症。所有患者术后均行CT复查,均未见肿瘤残留,术后随访10~52个月均未见复发及转移。结论微波消融治疗小肾癌是一种安全性好、并发症少、近期疗效好的方法,是小肾癌治疗的一个合理的选择,但目前远期疗效仍需进一步观察。  相似文献   
996.
目的将人文关怀融入护理工作,提高患者满意度。方法 2012年制定并实施"冬梅护理"人文关怀与细节服务举措,要求护士从患者入院到出院全过程,严格按照"冬梅护理"人文关怀与细节服务标准、规范、流程等实施护理。结果 2015年门急诊患者、住院患者、病房主管医生、护士长、责任护士、实习及进修生满意率分别为97.0%、98.1%、98.5%、95.0%、97.9%、98.0%。结论实施"冬梅护理"人文关怀与细节服务可提高护理满意度。  相似文献   
997.
非相干光—红光结合光动力疗法治疗葡萄酒色斑   总被引:4,自引:0,他引:4  
消除葡萄酒色斑且不留瘢痕。方法 采用非相干光-红光结合光动力疗法治疗11例。结果 全部病例获得良好疗效。结论认为用穿透皮肤深的红光有效照射和给药后立即照射能有效闭塞PWS,特别是紫红型和肥厚型PWS的畸形毛细血管。  相似文献   
998.
本文观测了44例老年冠心病患者血清脂质,丙二醛和超氧化物歧化酶,并与健康老年人对照比较,结果显示除胆固醇外其余各项指标2组间均有显著差异,老年CHD组MDA明显高于对照组,而SOD则与之相反。多元回归分析表明,血清低密度脂蛋白胆固醇,而血清高密度脂蛋白胆固醇与SOD呈显著正相关。提示老年CHD患者高脂血症与脂质过氧化间有一定关系,它对判断老年CHD的病情及预后有重要参考意义。  相似文献   
999.
AIM: To explore the role of the matrix metalloproteinase-9 (MMP-9) polymorphism in colorectal cancer (CRC) in a northeast Chinese population. METHODS: Genotyping of MMP-9 -1562C>T and 279R>Q polymorphisms was carried out on blood samples from 137 colorectal cancer patients and 199 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Multivariate logistic regression models were used to calculate adjusted odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: The distribution of MMP-9 -1562C>T and 279 R>Q genotype was not significantly associated with the risk of CRC. However, the risk of llymph node metastasis of CRC was increased in patients with the -1562T allele (OR = 2.601; 95% CI = 1.160-5.835; P = 0.022). The frequency of MMP-9 279RR RQ genotype was higher than the QQ genotype among CRC patients younger than sixty years old (OR = 0.102; 95% CI = 0.013-0.812; P = 0.012). CONCLUSION: Our results indicated that the MMP-9-1562C>T polymorphism affects lymph node metastasis of CRC. In addition, the MMP-9 279R allele may lead to a younger age of onset of colorectal cancer.  相似文献   
1000.
Glucagon-like peptide-1 (GLP-1) is an insulin secretagogue that secreted by intestinal L-cells. After binding with its receptor, GLP-1 stimulates glucose-dependent insulin secretion, β-cell prolifera-tion and differentiation as well as inhibits its apeptosis, decelerates gastric emptying, improves insulin sensi-tivity of periphery tissue. The long-acting GLP-1 analogues decrease hyperglycemia safely without weight gain and hypoglycemia and protect the function of pancreatic islet beta-cell. Using GLP-1 analogues at early stages of the disease,impaired beta-cell function and possibly beta-cell mass appear to be reversible. These agents axe, therefore, considered new therapeutic agents for the treatment of patients with type 2 diabetes.  相似文献   
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