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31.
ObjectiveThe postoperative role of adjuvant radiotherapy in non-metastatic head and neck adenoid cystic carcinoma (ACC) remains controversial. We analyzed adjuvant radiotherapy’s effect on surgical patient survival.MethodsPatients diagnosed with ACC from 2004 to 2015 in the Surveillance, Epidemiology, and End Results database were analyzed. The overall survival (OS) and disease-specific survival (DSS) of patients after adjuvant radiotherapy were assessed using the Kaplan–Meier and multivariate Cox methods. Propensity score matching (PSM) was performed to adjust confounders between patients with or without adjuvant radiotherapy; a forest plot was generated by subgroup analysis.ResultsThe study included 742 patients. In the PSM cohort, adjuvant radiotherapy did not improve OS or DSS. Radiotherapy was not a protective factor for OS or DSS in the univariate and multivariate Cox proportional hazard models. In the subgroup analysis, postoperative radiotherapy improved the OS of female and N1-stage patients and those with oropharyngeal tumors or over 79 years and the DSS of N1-stage patients.ConclusionsPostoperative radiotherapy showed different benefits in ACC patients, and postoperative radiotherapy recommendations should be individualized. Female and N1-stage ACC patients and those with oropharyngeal tumors or patients over 79 years without distant metastases postoperatively could benefit from adjuvant radiotherapy.  相似文献   
32.
目的:探讨微血管密度(microvessel density,MVD)的标记物CD105(endoglin)和金属基质蛋白酶2(matrixmet-alloproteinase-2,MMP-2)与腺样囊性癌(adenoid cystic carcinoma,ACC)临床病理参数及预后的相关性。方法:免疫组织化学SP法分别测定ACC41例、涎腺良性病变27例、正常涎腺组织块23例中CD105和MMP-2表达值,并结合ACC相关临床、病理因素和术后生存状况,分析二者表达的临床意义。结果:正常涎腺组织中无MVD和MMP-2的阳性表达。ACC组MVD和MMP-2的表达明显高于涎腺良性病变组(P=0.027);CD105标记的MVD值与TNM分期和组织学分型相关,MMP-2仅与TNM分期相关;Cox回归显示CD105标记的MVD可作为ACC的独立预后因素,MMP-2未得出同样结论;CD105标记的MVD高/低表达组复发率有明显差异;MVD和MMP-2表达呈正相关。结论:CD105与ACC复发转移密切相关,可望作为ACC有价值的预后指标。MMP-2表达和ACC的局部侵袭相关,但根据本研究还不能认为其是独立预后因素。  相似文献   
33.
目的探讨PCNP和β-catenin在涎腺腺样囊性癌(SACC)组织中的表达及其与临床病理特征的关系。方法收集2013年1月至2020年12月兰州大学第一医院30例接受手术切除的SACC患者的癌组织及10例癌旁组织标本。采用免疫组织化学SP法检测PCNP、β-catenin在SACC及癌旁组织中的表达情况,分析PCNP、β-catenin的表达与SACC临床病理特征的关系以及两者表达的相关性。结果 PCNP在SACC组织细胞核中大量表达,β-catenin在SACC肿瘤细胞中主要表达于细胞质及部分胞核。PCNP、β-catenin在SACC组织中的阳性表达率分别为83.3%(25/30)、66.7%(20/30),均显著高于癌旁组织(0/10),差异有统计学意义(P<0.01)。SACC组织中PCNP、β-catenin的表达与神经侵袭有关(P<0.05);SACC组织中PCNP与β-catenin的表达呈显著正相关(r=0.713,P<0.001)。结论 PCNP和β-catenin在SACC组织中的阳性表达率升高,推测其可能与SACC的发生发展相关。  相似文献   
34.
Infectious bronchitis virus (IBV) is an avian coronavirus that causes respiratory disease but can affect the reproductive tract of laying-type chickens. If infection occurs in pullets, false layer syndrome, which is characterized by the development of large, fluid-filled cystic oviducts, can occur. Recently, IBV strain DMV/1639 has been detected in parts of Canada and the U.S., where false layer syndrome has occurred, though it is not clear if IBV is the sole cause or if age at infection is an influencing variable. Our study investigates the role and timing of IBV infection on the development of false layer syndrome, using the IBV types DMV/1639 and Massachusetts (Mass). Six groups of 120 SPF chickens were challenged at either three, seven, or fourteen days of age, using either DMV/1639 or Mass IBV. Cystic oviducts were seen in all the challenged groups, and the pullets challenged at 14 days of age had fewer cystic oviducts than pullets challenged at 3 or 7 days of age. The highest percentage of severe histology lesion scores were seen in the 3-day challenge groups. The data collected in this experiment confirm that IBV DMV/1639 causes cystic oviducts and indicate that age at infection plays a role in the pathogenesis of false layer syndrome.  相似文献   
35.
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF.  相似文献   
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38.
目的:研究木犀草素对依赖于3,5-环腺苷酸(cAMP)的囊性纤维化跨膜电导调节因子(CFTR)Cl^-通道的激活作用。方法:利用稳定共表达人CFTR与一种对卤族元素敏感的荧光绿蛋白突变体(EYFP-H148Q)的Fischer大鼠甲状腺(FRT)细胞模型,测定木犀草素对CFTR介导的I^-内流速度。结果:木犀草素能够以剂量依赖的方式激活CFTR的I^-转运,其对CFTR Cl^-通道的激活效应具有作用迅速、可逆的特点。木犀草素在发挥激活作用时依赖于腺苷环化酶激动剂Forskolin的存在,其单独与细胞孵育不提高细胞内cAMP的水平。结论:发现了木犀草素能够以剂量依赖方式激活CFTR,并且初步确定了木犀草素通过直接与CFTR结合发挥作用。  相似文献   
39.
In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.  相似文献   
40.
胰腺囊性肿瘤(PCNs)是少见肿瘤,发病原因尚不明确,不良生活习惯(吸烟、饮酒、重咖啡、高脂高蛋白饮食等)、慢性胰腺炎、环境污染因素及遗传因素等是潜在致病因素。PCNs分为浆液性囊性肿瘤(SCN)、黏液性囊性肿瘤(MCN)、胰腺导管内乳头状黏液肿瘤(IPMN)和实性假乳头状瘤(SPN)四种类型。发病症状常不典型,早期诊断难。PCNs具有典型影像特点,单个影像检查技术对PCNs的准确性和局限性不同,CT检查在胰腺病变中仍是最基本、最主要的检查方式。MRI对于小的囊性病灶比CT更有优势。超声内镜(EUS)充分结合了内镜和超声检查的优势,与CT、MRI检查相辅相成,同时还可进行细针穿刺取病理及囊液分析。尽管PCNs大部分为良性,但只要达到切除标准,均应推荐患者进行手术治疗,严格遵循PCNs诊治流程,制订个体化PCNs治疗策略,使患者利益最大化。  相似文献   
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