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171.
68Ga-prostate specific membrane antigen (PSMA)-11 PET/CT has been widely used in the diagnosis of prostate cancer (PCa); however, the urine lead shielding resulting from the urinary metabolism of tracers may obstruct the detection of surrounding metastasis. In this research, the additive value of super early scanning in diagnosing primary lesions and metastasis in the pelvic cavity was evaluated. Firstly, the differentiation efficiency of 68Ga-PSMA-11 PET scanned at 3 min post-injection (min P.I.) was measured in PSMA-positive (22rv1 cells) and PSMA-negative (PC3 cells) model mice. Secondly, 106 patients were scanned at 3 min P.I. for the pelvic cavity and then scanned as a standard protocol at 45 min P.I. In the results, the differential diagnosis of PSMA expression was completely reflected as early as 3 min P.I. for mice models. For patients, when correlated with the Gleason score, the quantitative results of the super early scan displayed a comparable correlation coefficient with the routine scan. The target to bladder ratios increased from 1.44 ± 2.40 at 45 min to 10.10 ± 19.10 at 3 min (p < 0.001) for the primary lesions, and it increased from 0.99 ± 1.88 to 9.27 ± 23.03 for metastasis. Meanwhile, the target to background ratios increased from 2.21 ± 2.44 at 3 min to 19.13 ± 23.93 at 45 min (p < 0.001) for the primary lesions, and it increased from 1.68 ± 2.71 to 12.04 ± 18.73 (p < 0.001) for metastasis. In conclusion, super early scanning of 68Ga-PSMA-11 PET/CT added referable information for metastasis detection in order to avoid disturbing tracer activity in the urinary system.  相似文献   
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173.
Fatty acid synthase (FASN) is highly expressed in multiple types of human cancers and is recognized as one of the targets for treating cancer metastasis. α-Linolenic acid is an omega-3 essential fatty acid and it possesses various biological activities. The present study was designed to reveal the effects of α-linolenic acid on osteosarcoma and to reveal whether the mechanism of α-linolenic acid in anticancer activity may be related to FASN inhibition. The cytotoxicity of α-linolenic acid was assessed in osteosarcoma MG63, 143B, and U2OS cells. Cell viability was detected by the MTT assay. The protein expression level was detected by western blotting. Flow cytometry, Annexin V/propidium iodide dual staining, and Hoechst 33258 staining were performed to assess the apoptotic effects. Wound healing assay was applied to detect the inhibitory effect of α-linolenic acid on osteosarcoma cells migration. The results showed that α-linolenic acid downregulated FASN expression. α-Linolenic acid inhibited osteosarcoma cell proliferation and migration in a dose-dependent manner. In addition, α-linolenic acid regulated endoplasmic reticulum transmembrane receptors and signal protein expression in osteosarcoma cells. The findings of the present study suggested that α-linolenic acid suppresses osteosarcoma cell proliferation and metastasis by inhibiting FASN expression, which provides a basis as a potential target for osteosarcoma treatment.  相似文献   
174.
探讨CDK2在非小细胞肺癌组织中的表达与肺癌转移关系。将50例非小细胞肺癌组织分为转移组和非转移组,采用免疫组织化学和Western blot检测癌组织中CDK2蛋白的表达。结果表明:CDK2蛋白在肺癌细胞中主要位于细胞核。CDK2蛋白在肺癌组织中的表达水平显著高于癌旁组织(P0.05)。CDK2蛋白高水平表达与肺癌淋巴结转移呈正相关(P0.05),但与肿瘤类型无关(P0.05)。CDK2的过表达可能与肺癌的形成有关,并与淋巴转移有关。  相似文献   
175.
肺癌是最常见的恶性肿瘤之一。肿瘤癌很容易发生转移。实验以17例肺癌(5例肺腺癌、1例腺鳞癌、7例肺鳞癌及4例小细胞末分化癌)的原发灶、癌旁正常组织及转移淋巴结为材料,采用PCR及非放射性标记的RNA斑点杂交分析LTR在基因组的存在及其表达情况。研究结果发现:LTR序列在17例肺癌病人的正常组织及肿瘤组织的基因组中普遍存在,LTR致肺癌转移与其插入基因组中无关;LTR致肺癌转移与其表达增高有关,而且其高表达与小细胞肺癌的转移无关,而与非小细胞肺癌的转移密切相关。提示LTR参与了非小细胞肺癌的转移过程。实验结果为从细胞系获得的结论提供了进一步的证据。  相似文献   
176.
胸部骨骼多发性骨髓瘤和骨转移瘤的X线及CT鉴别   总被引:3,自引:0,他引:3  
目的 :探讨多发性骨髓瘤 (MM)与骨转移瘤 (BM)胸部骨骼受侵的X线及CT所见的不同。方法 :搜集经骨髓涂片或活检 ,病理确诊MM 36例 ,另搜集手术病理确诊为原发恶性肿瘤并骨受侵 6 7例和骨破坏病理活检为转移瘤但未找到原发灶的 3例。对两组病例胸部X线及CT影像进行分析比较。结果 :锁骨、肩胛骨、胸骨和肱骨上段受侵发生率二者差异有显著性 ,而肋骨则无显著性 ,但破坏呈膨胀型或圆、类圆型时 ,二者发生率差异有显著性 ;并发软组织肿块之发生率二者差异无显著性 ,但CT上二者各有不同特征。锁骨及肩胛骨受侵 ,呈圆、类圆型破坏发生率二者差异有高度显著性。BM胸片上可有原发及继发肺癌 ,纵隔、肺门淋巴结转移征象 ,而MM则极为少见。结论 :根据胸部各骨受侵部位、破坏类型、软组织肿块CT表现 ,有无原发、继发肺癌征象 ,在胸片上是有可能鉴别MM与BM的  相似文献   
177.
Potent, cell-permeable, and subtype-selective sialyltransferase inhibitors represent an attractive family of substances that can potentially be used for the clinical treatment of cancer metastasis. These substances operate by specifically inhibiting sialyltransferase-mediated hypersialylation of cell surface glycoproteins or glycolipids, which then blocks the sialic acid recognition pathway and leads to deterioration of cell motility and invasion. A vast amount of evidence for the in vitro and in vivo effects of sialyltransferase inhibition or knockdown on tumor progression and tumor cell metastasis or colonization has been accumulated over the past decades. In this regard, this review comprehensively discusses the results of studies that have led to the recent discovery and development of sialyltransferase inhibitors, their potential biomedical applications in the treatment of cancer metastasis, and their current limitations and future opportunities.  相似文献   
178.
目的探讨MSCT、高场MR对肝转移瘤(Hepatic Metastases,HMs)介入治疗的指导意义。方法21例HMs行介入治疗。介入治疗前先行MSCT、高场MRI动态增强扫描检查及血管重建。结果MRI于平扫、动态增强扫描各期对病灶的检出率均高于MSCT,尤其增强扫描对直径〈1cm的病灶检出更显著高于MSCT(P〈0.05)。血管重建显示情况:所有病例通过MSCTA均能显示3级以下肝动脉,与DSA完全相符;MRA成功显示16例,余5例由于患者呼吸配合欠佳而使血管显示不理想。所有病例通过MSCTA均能显示4级以下门静脉肝内分支;MRA成功显示13例,3例显影较淡而不能清晰显示4级以下门静脉肝内分支,余5例由于患者呼吸配合欠佳而使血管显示不理想。DSA肝动脉造影可间接显示门静脉,但3级以下肝内分支大都显示不清。结论MSCT、高场MR的综合应用能提高HMs的检出率,通过快速的动态增强扫描能重建出高质量的肝动脉及门静脉血管像,且较DSA在诊断方面具有易操作性和非创性的优势,从而为合理制定HMs介入治疗方案提供重要的指导作用。  相似文献   
179.
目的:研究转录因子Twist、上皮性钙黏附素(E-Cadherin)和波形蛋白(Vimention)在非小细胞肺癌(NSCLC)中的表达,探讨其与非小细胞肺癌浸润转移及预后之间的关系.方法:采用SP免疫组织化学、Western blot和RT-PCR方法检测80例非小细胞肺癌组织Twist、E-Cadherin和vimention蛋白和mRNA,20例癌旁正常组织作对照.另采用免疫细胞化学法检测68例非小细胞肺癌所致胸腔积液中肿瘤细胞的表达.结果:Twist和Vimentin在NSCLC组织及NSCLC胸水标本中的表达显著高于癌旁正常肺组织(P<0.01);E-cadherin在NSCLC组织及NSCLC胸水标本中表达显著低于癌旁正常肺组织(P<0.01);NSCLC组织中Twist及E-cadherin表达均与组织分化,临床分期及淋巴结转移情况密切相关(P<0.01);并且Twist表达与E-cadherin表达降低(P<0.01)和Vimentin的表达上调(P<0.01)之间都存在相关性.结论:Twist蛋白在非小细胞肺癌组织及胸腔转移灶中过度表达,可能通过分别上调和下调Vimentin、E-ead-h...  相似文献   
180.
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