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61.
将194例小肝癌患者纳入小肝癌组,185例肝细胞结节患者纳入结节组,所有患者均行MRI扩散加权成像(DWI-MRI),评估患者在DWI-MRI上的形态学表现及ADC值,检测患者血清AFP水平,比较不同检测方法诊断小肝癌的准确度、灵敏度、特异度。结果显示,应用DWI-MRI联合血清AFP诊断小肝癌的特异度、灵敏度和准确度均显著高于单独应用DWI-MRI,或血清AFP(P<0.05)。表明DWI-MRI联合血清AFP对小肝癌的诊断价值显著,可为病情评估提供切实可行的参考。  相似文献   
62.
Nasopharyngeal carcinoma (NPC) is a common malignant head and neck tumor. Drug resistance and distant metastasis are the predominant cause of treatment failure in NPC patients. Hispidulin is a flavonoid extracted from the bioassay-guided separation of the EtOH extract of Salvia plebeia with strong anti-proliferative activity in nasopharyngeal carcinoma cells (CNE-2Z). In this study, the effects of hispidulin on proliferation, invasion, migration, and apoptosis were investigated in CNE-2Z cells. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and the colony formation assay revealed that hispidulin could inhibit CNE-2Z cell proliferation. Hispidulin (25, 50, 100 μM) also induced apoptosis in a dose-dependent manner in CNE-2Z cells. The expression of Akt was reduced, and the expression of the ratio of Bax/Bcl-2 was increased. In addition, scratch wound and transwell assays proved that hispidulin (6.25, 12.5, 25 μM) could inhibited the migration and invasion in CNE-2Z cells. The expressions of HIF-1α, MMP-9, and MMP-2 were decreased, while the MMPs inhibitor TIMP1 was enhanced by hispidulin. Moreover, hispidulin exhibited potent suppression tumor growth and low toxicity in CNE-2Z cancer-bearing mice at a dosage of 20 mg/kg/day. Thus, hispidulin appears to be a potentially effective agent for NPC treatment.  相似文献   
63.
发展了一种基于免疫磁性纳米球(IMNs)快速、高效、准确检测淋巴结转移癌细胞(LNMCCs)的策略.首先利用本课题组发展的方法制备了具有磁性和生物靶向双功能的IMNs,然后利用IMNs通过免疫磁分选对淋巴结转移癌病人淋巴结穿刺物中的LNMCCs进行分离和富集,最后采用瑞氏染色法和免疫细胞化学(ICC)对富集的LNMCCs进行鉴定,实现对LNMCCs的快速高效准确检测.免疫磁分选实现了LNMCCs的分离和富集,可以有效降低淋巴结穿刺物中的背景干扰;瑞氏染色法和ICC鉴定为准确诊断提供了更多可靠依据,因此,传统细胞学敏感性、特异性和诊断准确率不高的问题得到明显改善.其次,淋巴结穿刺物与IMNs的孵育只需5 min,简便快速,完整保留了LNMCCs的形态学特征,为淋巴结转移癌(LNMC)的分类和后续病理学分析提供了重要基础.此外,IMNs对淋巴结穿刺物中上皮来源癌细胞的特异性捕获可以确诊捕获的细胞为LNMCCs,实现了LNMC和恶性淋巴瘤的鉴别诊断.最后,采用本方法检测了110例病人淋巴结穿刺物中的LNMCCs,总诊断准确率高达98.2%,特异性为100.0%,敏感性为98.0%,相比于传统细胞学诊断都有明显的提高.因此,IMNs用于LNMC病人淋巴结穿刺物中LNMCCs的检测是一次新的尝试,为LNMC的诊断和研究提供了新思路.  相似文献   
64.
ABSTRACT

The Ductal carcinoma in situ (DCIS) model has wide applications in the diagnosis of breast cancer, and has been attracted much attention in recent years. In this paper, an effective method has been provided for solving the direct problem of the DCIS model. Moreover, the uniqueness result is established for a kind of inverse problems of DCIS model. Based on the uniqueness theorem, an optimization method has been developed for dealing with the related inverse problem of the DCIS model. The numerical experiments show that the algorithms in this paper are efficient, accurate, robust against noise and fast.  相似文献   
65.
《Mendeleev Communications》2020,30(6):706-708
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  相似文献   
66.
采用微核检测技术,研究了亚硒酸钠对启东肝癌高发区不同类型饮用水诱发健康人外周血淋巴细胞微核的拮抗作用。结果表明:(1)各实验水体对细胞的毒性作用,宅沟水〉泯沟水〉自来水〉双蒸水。微核率随着实验水体剂量的增加而升高;(2)1mg/L的亚硒酸钠浓度对泯沟水,自来水诱发的微核效应有是显的抑制和/或拮抗作用,呈现明显的剂量-效应关系,提示肝癌高发区饮用水体中确存在与肝癌发病相关的致畸因子,补硒确有防与治原  相似文献   
67.
Having made use of the micropipette aspiration technique, we here investigated the viscoelastic properties of hepatocellular carcinoma (HTC) cells from the view of cell cycle. The synchronous G1 and S phase cells were achieved through thymine-2-desoryriboside and colchicine sequential blockage method and double thymine-2-desoryriboside blockage method, respectively. The synchronization results detected with flow cytometer showed that it could meet the requirements of the experiments nicely. Experimental results were analyzed with a standard linear solid viscoelastic model, in which an elastic element, K1, is in parallel with a Maxwell element composed of another elastic element, K2, in series with a viscous element, μ. The results indicated that high K1, K2 values and low μ value was the general characteristics of the cells; G1 phase cells had higher K1 values and low μ value than S phase cells, which endowed G1 phase cells with higher elasticity and faster passive deformability than S phase cells. The results maybe also reflected the difference of cytoskeleton between G1 and S phase cells, and suggested that G1 phase cells were more suitable for surviving and metastasis in blood circulation than S phase cells.  相似文献   
68.
57例胃癌癌灶内锌值为(13.740±4.150)×10~(-6),低于癌边缘组织(15.677±4.567)×10~(-6)(P<0.01),亦低于正常组织(15.897±3.580)×10~(-6)(P<0.01)。癌灶铜值为(7.91±6.19)×10~(-6),高于正常组织(5.62±12.01)×10~(-6)(P<0.05),癌灶铜/锌比值亦高于正常组织(P<0.01),但与边缘组织无显著性差异。分化较好的胃腺癌与未分化癌间七种微量元素含量均无显著性差异。这些结果提示,胃癌组织中锌值的降低与铜/锌比值的升高可作为胃癌的辅助诊断指标,而且锌值的检测更具意义。但与分化程度无关。  相似文献   
69.
3-(Fluoroacyloxy)quinoline-2,4(1H,3H)-diones react with triethyl phosphite to afford either the product of the Perkow reaction or the corresponding 4-ethoxyquinolin-2(1H)-one. In both reactions, the fluorocarboxylate anion acts as the leaving group. For the corresponding 3-(fluoroiodoacetoxy) derivative this observation precludes the application of the intramolecular Wittig-Horner synthesis to modify quinoline-2,4(1H,3H)-diones by the annulation of a fluorinated but-2-enolide moiety.  相似文献   
70.
Introduction Gastriccancerisoneofthemostcommonlyen counteredmalignantdiseasesworldwide,especiallyin AsiaandAfrica[1].Thecombinationofoperation,chemotherapyandradiotherapyisusedfortreatinggas triccarcinoma.However,the5yearsurvivalrateof patientsofgastricca…  相似文献   
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