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101.
BACKGROUND: Localized low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma can regress after Helicobacter pylori eradication, but IgV(H) gene monoclonality may persist. We studied the long-term histological and molecular follow-up of 24 patients and the possible association of t(11;18) with the persistent monoclonality. PATIENTS AND METHODS: From January 1994, 24 untreated patients with stage I low-grade gastric MALT lymphoma associated with H. pylori were prospectively studied. They all received eradication treatment and were sequentially followed-up with endoscopies for histological and molecular studies. Rearrangement of the IgV(H) gene was studied by PCR analysis. MALT1 locus alterations were studied by FISH. RESULTS: Twenty-two of the 24 patients (91%) achieved disappearance of the lymphoma. Eighteen (82%) of the 22 histologically cured patients and 16 of the 19 (84%) with long follow-up had monoclonality. Three patterns of development of IgV(H) gene rearrangements were observed: four patients (21%) had polyclonal rearrangements; eight (58%) had maintained/intermittent monoclonality and four (21%) had occasional monoclonality, mostly after H. pylori reinfection. Only one patient (6%) with persistent monoclonality relapsed. The remaining 18 patients maintained the remission, despite the persistent monoclonality in 15, for a median of 66 months (range 20-113). t(11;18) was not found in any of the patients with persistent monoclonality. Time and the number of endoscopies performed were not related with the occurrence of monoclonality. CONCLUSIONS: In stage I low-grade gastric MALT lymphoma eradication of H. pylori achieves prolonged histological remission in 90% of patients, but molecular remission is not accomplished in most cases. Molecular disease persists for years, but is not associated with t(11;18).  相似文献   
102.
Allele and genotype frequencies for eight DNA polymorphisms (HUMTH01, HUMVWA31A, D3S1358, D8S1179, D18S51, D19S253, YNZ22 and HLA-DQalpha) were determined in a population sample of Aymara Indians from Bolivia using PCR. No deviations of the observed allelic frequencies from Hardy-Weinberg equilibrium were found for all the systems studied. Significant differences in the allele frequencies were found between the Aymara and Quechua populations only for HUMVWA31A, which suggests a certain degree of genetic differentiation between the two populations.  相似文献   
103.
The feasibility of synthesizing compounds containing the P–18F bond has been demonstrated by labelling the pesticide, cholinesterase inhibitor Dimefox (N,N,NN′‐tetramethylphosphorodiamidic fluoride) with F‐18. Radiolabelling was achieved in high radiochemical yield (96%) by nucleophilic substitution of the chloro group attached to phosphorus, in the oxidation state P(V), by 18F? (activated with tetrabutylammonium carbonate in acetonitrile). Given the large number of important biological molecules possessing phosphorus such as oligonucleotides, phospholipids as well as phosphorylated proteins, sugars and steroids, this new labelling chemistry may provide an additional route to radiolabelling these biologically important compounds for use in PET. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
104.
A fluorine‐18 labeled analog of the widely used chemotherapeutic agent cyclophosphamide was synthesized as a tracer for prognostic imaging with positron emission tomography. 2‐[(2‐Chloro‐2′‐[18F]fluoroethyl)amino]‐2H‐1,3,2‐oxazaphosphorinane‐2‐oxide (18F‐fluorocyclophosphamide), was prepared by direct halogen exchange reaction from the parent cyclophosphamide. In small‐scale syntheses, radiochemical yields of up to 4.9% and specific activities of 960 Ci/mmol were achieved in a total synthesis time of 60–75 min. The [18F]‐labeled cyclophosphamide analog with radioactive purity >99% and chemical purity >96% was suitable for in vivo (microPET imaging) and ex vivo studies of a murine model of human breast tumors. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
105.
106.
目的:探讨E_2、P、β-hCG、IL-18、PDCD-5在稽留流产患者血清和绒毛组织的表达及其预警意义。方法:选取2018年1—6月我院收治稽留流产妇女30例作为实验组,同期就诊正常早孕妇女(要求终止妊娠)30例为对照组,测定患者血清和绒毛组织E_2、P、β-hCG、IL-18、PDCD-5表达水平,通过统计学软件分析这些指标与孕妇发生稽留流产的相关性。结果:与对照组相比,实验组受试者血清、绒毛组织中E_2、P和β-hCG水平明显较低(P<0. 05),IL-18和PDCD-5水平明显较高(P<0. 05)。Logistic多元回归分析结果显示,血清E_2、P、β-hCG低表达以及IL-18、PDCD-5高表达为孕妇发生稽留流产的危险因素(P<0. 05)。结论:血清、绒毛组织中E_2、P、β-hCG低表达以及IL-18、PDCD-5高表达与孕妇稽留流产发生有关,具有一定预警作用。  相似文献   
107.
18F-FDG PET/CT在探查腹膜转移性肿瘤中的价值   总被引:1,自引:0,他引:1  
目的:评价18F-FDG PET/CT探查腹膜转移瘤的价值。方法:39例有腹部原发恶性肿瘤手术史患者行PET/CT首次和延迟扫描,在PET/CT图像上记录病灶大小、分布,结果与常规CT比较。测量62个病灶和对照组32例腹部无病变患者的肠管SUVmax。所有病例经手术、病理、影像学和肿瘤标记物随访作出最后诊断。结果:最终确认39例中31例腹膜转移瘤,病灶均为结节状或沿腹膜条片状分布,多位于肝脏周围和盆腔腹膜,其他部位腹膜少见。PET/CT漏诊的4个病灶主要位于肝脏周围,1例因化疗不久病灶FDG低摄取而漏诊,因此敏感性为87.1%,特异性为87.1%。CT仅检出12例转移瘤。转移瘤SUVmax明显高于对照组肠管SUVmax(P=0.0000)。结论:18F-FDG PET/CT能够较CT更早、更多地检出腹膜转移瘤,病灶体积小、位于基础摄取较高的肝脏周围是漏诊主要原因,而结合原发肿瘤病史和肿瘤标记物检查有利于诊断。  相似文献   
108.
Aims: Inflammation is involved in various processes of atherosclerosis development. Serum C-reactive protein (CRP) levels, a predictor for cardiovascular risk, are reportedly reduced by statins. However, several studies have demonstrated that CRP is a bystander during atherogenesis. While S100A12 has been focused on as an inflammatory molecule, it remains unclear whether statins affect circulating S100A12 levels. Here, we investigated whether atorvastatin treatment affected S100A12 and which biomarkers were correlated with changes in arterial inflammation. Methods: We performed a prospective, randomized open-labeled trial on whether atorvastatin affected arterial (carotid and thoracic aorta) inflammation using18fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) and inflammatory markers. Thirty-one statin-naïve patients with carotid atherosclerotic plaques were randomized to either a group receiving dietary management (n=15) or one receiving atorvastatin (10mg/day,n=16) for 12weeks.18F-FDG-PET/CT and flow-mediated vasodilation (FMD) were performed, the latter to evaluate endothelial function. Results: Atorvastatin, but not the diet-only treatment, significantly reduced LDL-cholesterol (LDL-C, -43%), serum CRP (-37%) and S100A12 levels (-28%) and improved FMD (+38%).18F-FDG-PET/CT demonstrated that atorvastatin, but not the diet-only treatment, significantly reduced accumulation of18F-FDG in the carotid artery and thoracic aorta. A multivariate analysis revealed that reduction in CRP, S100A12, LDL-C, oxidized-LDL, and increase in FMD were significantly associated with reduced arterial inflammation in the thoracic aorta, but not in the carotid artery. Conclusions: Atorvastatin treatment reduced S100A12/CRP levels, and the changes in these circulating markers mirrored the improvement in arterial inflammation. Our observations suggest that S100A12 may be an emerging therapeutic target for atherosclerosis.  相似文献   
109.
胸痹心痛与血清IL-6、IL-1O、IL-18水平关系的研究   总被引:4,自引:0,他引:4  
目的 研究胸痹心痛(冠心病心绞痛)发病与血清IL—6、IL—10、IL—18水平变化的关系。方法 观察胸痹心痛患者血清IL—6、IL—10、IL—18的水平并与健康人对比。结果 与稳定型心绞痛患者血清IL—10水平相比,不稳定型心绞痛患者血清IL—10水平较低,而IL—6水平较高;胸痹心痛患者IL—18水平均高于对照组。结论 血清IL—6、IL—10、IL—18水平的变化与胸痹心痛的发病密切相关。  相似文献   
110.
目的研究18β-甘草次酸(18β-glycyrrhetinic acid,18β-GA)对人高转移卵巢癌HO-8910PM细胞中Fas,FasL表达的影响,探讨Fas,FasL对卵巢癌细胞凋亡的作用机制。方法不同浓度药物作用HO-8910PM细胞,MTT法检测细胞的生长增殖,流式细胞仪检测细胞周期,FITC法检测Fas,FasL的蛋白表达情况。结果 18β-GA对高转移卵巢癌细胞HO-8910PM的生长和增殖具有显著的抑制作用;药物使8910PM细胞周期阻滞于G1期,凋亡增加。FITC检测发现Fas,FasL蛋白表达上调(P<0.05)。结论 18β-GA通过上调HO-8910PM中Fas,FasL蛋白表达,促使细胞凋亡,抑制细胞增殖,提示18β-GA可能成为治疗卵巢癌的潜在药物。  相似文献   
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