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目的 探讨十二指肠肿瘤血流量存在的异质性及容积灌注CT成像对降低肿瘤异质性的影响。方法 纳入我院2013年1月至2014年11月十二指肠结节病例的132例,其中腺癌48例,间质瘤52例,淋巴瘤32例。所有的病例均行单层面灌注CT和容积灌注CT成像扫描,比较两者对十二指肠恶性肿瘤的诊断效能,采用变异系数评价两者在影像学异质性的差异,评价肿瘤影像学异质性对十二指肠恶性肿瘤的影响。结果 容积灌注CT成像与单层面灌注CT诊断恶性结节的效能其敏感性、特异性、准确性、阴性预测值、阳性预测值比较均无明显差别(P0.05);中高分化组及低分化组两个亚组的容积灌注CT成像的变异系数也均小于单层面灌注CT的变异系数,组间相比具有统计学差异(P0.05);血流量差异性的大小相比具有统计学差异(P0.05)。结论 容积灌注CT成像与单层面灌注CT检查在诊断效能上无明显差异,稳定性好,肿瘤影像学异质性对评价十二指肠肿瘤血流量有着一定影响,容积灌注CT成像能够降低肿瘤异质性的影响。  相似文献   
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Background

Clear cell renal cell carcinoma (ccRCC) is known to occur across the adult lifetime traversing the spectrum of age-related organismal changes. Little is known as to how the aging process may affect the course of renal cell carcinoma (RCC) and the repertoire of genes involved.

Methods

Using The Cancer Genome Atlas (n?=?436) and Cancer Genomics of the Kidney (n?=?89) datasets, we applied regression analysis to examine associations between patient age and gene expression profiles in ccRCC tumors and normal kidney tissues. Pathway enrichment analysis was performed to identify cellular process that is affected by aging in ccRCC. Moreover, connectivity mapping analysis was used to predict age-dependent response to drug treatments.

Results

Our analysis revealed different age-dependent gene expression spectra in ccRCC and normal kidney tissues. These findings were significant and independently reproducible in both datasets examined. Age up-regulated genes, showing higher expression in older patients, were significantly enriched (false discovery rate <0.05) in normal tissues for pathways associated with immune response and extracellular matrix organization, whereas age up-regulated genes in tumors were enriched for metabolism and oxidation pathways. Strikingly, age down-regulated genes in normal cells were also enriched for metabolism and oxidation, while those in tumors were enriched for extracellular matrix organization. Further in silico analysis of potential drug targets predicted preferential efficacy of Phosphoinositide 3-kinase inhibitor or immunotherapy in association with age.

Conclusion

We report on previously unrecognized associations between age and molecular underpinnings of RCC, including age-associated expression of genes implicated in RCC development or treatment.  相似文献   
65.
Background and Aims: Gastric antral vascular ectasia (GAVE) is commonly found in patients with cirrhosis, but it is also associated with other diseases in the absence of cirrhosis. Whether GAVE confers a different severity of gastrointestinal (GI) bleeding between patients with and without cirrhosis remains unknown. We aim to examine whether there is a difference in clinically significant GI bleeding due to GAVE in patients with or without cirrhosis. Methods: This is a retrospective case-control study of patients who were diagnosed with GAVE between January 2000 and June 2014. Patients were categorized into cirrhosis and noncirrhosis groups, and those with an additional GI bleeding source were excluded. Univariate comparisons and multivariable models were constructed using logistic regression. Results: In total, 110 patients diagnosed with GAVE on esophagogastroduodenoscopy (EGD) were included in our analysis; 84 patients had cirrhosis (76.4%) and 26 (23.6%) did not. Active GI bleeding was more prevalent in patients without cirrhosis (63.4% vs. 32.1%, p=0.003) despite similar indications for EGD, and endoscopic treatment with argon plasma coagulation (APC) was required more often in this group, approaching statistical significance (27% vs. 10.7%, p=0.056). There was no difference in bleeding severity, as evidenced by similar re-bleeding rates, surgery, or death attributed to uncontrolled bleeding. The strongest independent risk factor for GI bleeding was the absence of cirrhosis (odds ratio (OR): 5.151 (95% confidence interval (CI): 1.08-24.48, p=0.039). Conclusions: Patients with GAVE in the absence of cirrhosis are at higher risk for active GI bleeding and require more frequent endoscopic treatment than similar patients with cirrhosis. It may be worthwhile to treat GAVE in this population even in the absence of active bleeding.  相似文献   
66.
BACKGROUND Accurate detection of gastric infection by Helicobacter pylori(H.pylori) and premalignant lesions are important for effective provision of treatment,preventing the development of gastric neoplasia.Optical enhancement systems with optical magnification improved the identification of mucosal superficial and vascular patterns in patients with dyspepsia.AIM To evaluate an optical enhancement system with high-definition magnification,for diagnosis of normal gastric mucosa,H.pylori-associated gastritis,and gastric atrophy.METHODS A cross-sectional,nonrandomized study from November 2015 to April 2016 performed in a single-tertiary academic center from Ecuador.Seventy-two consecutive patients with functional dyspepsia according to the Rome III criteria,were tested for H.pylori using a stool antigen test and were assigned to an Hp+group or an Hp-control group.Esophagogastroduodenoscopy with highdefinition optical magnification and digital chromoendoscopy was performed,and patients were classified into 4 groups,in accordance to the microvasculararchitecture pattern of the mucosa.Interobserver and intraobserver agreement among operators were calculated.RESULTS Of the 72 participants,35 were Hp+ and 37 were Hp-.Among 10 patients with normal mucosal histology in biopsy samples,90% had a Type I pattern of microvascular architecture by endoscopy.Among participants with type IIa and type IIb patterns,significantly more were Hp+ than Hp-(32 vs 8),and most(31 out of 40) had histological diagnoses of chronic active gastritis.Two of the three participants with a histological diagnosis of atrophy had a type III microvascular pattern.The type I pattern predicted normal mucosa,type IIa–IIb predicted H.pylori infection,and type III predicted atrophy with sensitivities of 90.0%,91.4%,and 66.7%,respectively.The intraobserver and interobserver agreements had kappa values of 0.91 and 0.89,respectively.CONCLUSION High-definition optical magnification with digital chromoendoscopy is useful for diagnosis of normal gastric mucosa and H.pylori-associated gastritis with high accuracy,but further studies are needed to determine whether endoscopic diagnosis of gastric atrophy is feasible.  相似文献   
67.
目的研究~(18)F-FDG PETCT显像对膀胱癌的诊断价值。方法选取我院核医学科2013年3月-2015年2月收治的34例可疑膀胱癌患者,术前分别采用增强CT和~(18)F-FDG PETCT显像进行诊断,通过参考手术病理结果回顾性分析~(18)F-FDG PETCT显像诊断的效果。结果该34例经手术病理观察均确诊为移行细胞癌,增强CT、~(18)F-FDG PETCT显像诊断准确度分别为91.18%、94.12%,差异无统计学意义(P0.05);术中共有11例膀胱肿瘤出现盆腔淋巴结或邻近组织转移、浸润,~(18)F-FDG PETCT显像诊断准确度为72.73%,明显高于增强CT(27.27%),具有统计学意义(P0.05)。结论 ~(18)F-FDG PETCT显像和增强CT均是临床诊断膀胱癌的有效方法,但~(18)F-FDG PETCT显像在观察膀胱肿瘤病灶的转移和对邻近组织的浸润效果较好,对指导临床诊断和了解肿瘤病变具有重要参考价值。  相似文献   
68.
ObjectiveProgrammed death ligand 1 (PD-L1) has been reported to be connected to prognosis in individuals with malignant pleural mesothelioma (MPM), although there is no consensus based on data from previous studies. Accordingly, this quantitative meta-analysis investigated prognostic and clinicopathological utility of PD-L1 in patients with MPM.MethodsA comprehensive search of the PubMed, Web of Science, Embase, and Cochrane Library databases for articles published up to October 4, 2019 was performed. Studies using immunohistochemical techniques to detect/quantify the expression of PD-L1 in MPM tissue were enrolled in the analysis. The combined hazard ratio (HR) and corresponding 95% confidence interval (CI) was applied to assess the association between PD-L1 expression and overall survival (OS).ResultsA total of 11 studies comprising 1606 patients was included in the present meta-analysis. For OS, pooled data revealed an HR of 1.50 (95% CI 1.32–1.70; p < 0.001), suggesting that patients with PD-L1 overexpression experience inferior OS. Subgroup analysis revealed that elevated PD-L1 remained a significant prognostic indicator for worse OS, irrespective of sample size, cut-off value, ethnicity, and Newcastle-Ottawa Scale score. Moreover, PD-L1 overexpression was associated with non-epithelioid histology (odds ratio 4.30 [95% CI 1.89–9.74]; p < 0.001).ConclusionsResults of this meta-analysis show that elevated expression of PD-L1 could be a factor predicting poorer survival in patients with MPM.  相似文献   
69.
Background and objectivesPatients with cancer experience many side effects due to its nature and usual treatments. Sleep disorders and anorexia are the most commonly reported symptoms in cancer patients undergoing chemotherapy. The present study aimed to investigate the effect of Benson's Relaxation Response (BRR) on sleep quality and anorexia in cancer patients undergoing chemotherapy.Methodology and participantsIn the present clinical trial, a total of 84 patients were enrolled and randomly divided into two groups of experimental and control. Benson's relaxation response was administered to the experimental group twice a day over 5 consecutive days. Data was collected using St. Mary's Hospital Sleep Questionnaire (SMHSQ) and anorexia questionnaire with Visual Analog Scale (VAS).ResultsThe results of our study showed a significant improvement in the sleep quality in the experimental group at 24 (p = 0.02) and 48 (p = 0.001) hours after the intervention compared to the control group. Benson's relaxation response (BRR) also had a significant effect on the anorexia in the experimental group at 24 (7.5 ± 1.6) and 48 (6.9 ± 2.1) hours after the intervention compared to the control group. No side effects were reported during the study and follow-up period.ConclusionBenson's relaxation response as a complementary method may improve sleep quality and anorexia in cancer patients undergoing chemotherapy. Further studies with greater sample size and longer follow-up period are needed to confirm the current findings.  相似文献   
70.
目的探讨奥沙利铂如何调控MAPK通路,抑制胃癌细胞的增殖。方法NCBI检索文献,利用TargetScan、StarBase和miRBase数据库,进行GO分析与KEGG通路富集,找到相关miRNAs,预测靶基因。应用Real-time PCR、MTT、Hoechst33258、流式细胞术、细胞划痕实验、Western blot等方法分析人胃癌SGC-7901细胞的增殖、细胞周期、侵袭及蛋白表达情况。结果胃癌细胞中miR-7-5p显著低表达,RAF1与miR-7-5p存在互靶关系。miR-7-5p mimics与奥沙利铂均可促进SGC-7901细胞的凋亡,提高G1期细胞百分率(P<0.05),降低侵袭、迁移速度。caspase3、caspase9蛋白表达升高,Bcl-2/Bax比值降低(P<0.05)。结论过表达miR-7-5p与奥沙利铂均可促进胃癌SGC-7901细胞的凋亡,提示奥沙利铂可能通过上调miRNA-7-5p促进SGC-7901细胞的凋亡,降低侵袭、迁移速度。  相似文献   
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