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31.
目的观察阿帕替尼联合曲妥珠单抗杀伤胃癌NCI-N87细胞的协同增敏作用并探讨可能作用机制。方法CCK-8法检测空白对照组、曲妥珠单抗组(0.1、1、10μg/ml)、阿帕替尼组(1μmol/L)及曲妥珠单抗(0.1、1、10μg/ml)+阿帕替尼(1μmol/L)组对NCI-N87细胞的增殖抑制作用,流式细胞术检测NCI-N87细胞凋亡,Western blotting检测HER-2、VEGFR2、Bax、Bcl-2蛋白表达。结果CCK-8检测提示曲妥珠单抗、阿帕替尼能够抑制NCI-N87细胞增殖,在一定浓度范围内作用呈浓度依赖性和时间依赖性(P<0.01);q值计算提示曲妥珠单抗与阿帕替尼具有协同抑制NCI-N87细胞增殖的作用。流式细胞术检测显示联合组NCI-N87胃癌细胞凋亡较单药组明显升高(P<0.05),其中空白对照组、阿帕替尼组(1μmol/L)、曲妥珠单抗(0.1μg/ml)组及曲妥珠单抗(0.1μg/ml)+阿帕替尼(1μmol/L)组的凋亡率分别为(3.0±1.28)%、(5.8±1.63)%、(8.0±3.92)%和(21.6±6.85)%。曲妥珠单抗+阿帕替尼组与空白对照组、曲妥珠单抗及阿帕替尼单药组比较,HER-2蛋白表达显著下调(P<0.05);曲妥珠单抗+阿帕替尼组与空白对照组比较,Bcl-2蛋白表达、Bcl-2/Bax比值明显降低(P<0.01)。结论阿帕替尼联合曲妥珠单抗可能通过下调HER-2蛋白及调控凋亡相关蛋白Bcl-2、Bax的表达,协同抑制NCI-N87细胞增殖和促进细胞凋亡。  相似文献   
32.
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   
33.
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   
34.
Background: Nivolumab has been approved for use in advanced gastric cancer (GC) after third-line chemotherapy in Japan. However, it remains difficult to predict favorable nivolumab response before treatment. Methods: We evaluated the clinical course with a focus on the chronological changes in neutrophil/lymphocyte ratio (NLR) throughout the chemotherapy and assessed the relationship between nivolumab response and chronological changes in NLR before nivolumab administration. Results: We experienced nine cases who received nivolumab monotherapy for unresectable advanced or postoperative recurrent GC. Nivolumab was used as third-line chemotherapy in all patients, and partial response (PR) and stable disease (SD) were observed in two patients each. Nivolumab treatment resulted in progressive disease (PD) in five patients. In patients with PR or SD, changes in the NLR tended to correspond to the response of target metastatic lymph nodes to first- and second-line chemotherapy. In the four cases with PR or SD following nivolumab, ∆NLRresponses that was the difference in the degree of decline during the most effective pretreatment chemotherapy were 1.39, 0.73, 1.62, and 1.22. However, the patients with PD showed lower ∆NLRresponses, at 0.66, 0.66, 0.25, 0.13, and -0.05 in the five cases. Mean ∆NLRresponses in the patients with PR or SD and patients with PD were 1.17 and 0.33, respectively (P = 0.0008). Conclusions: We experienced nine GC cases treated with nivolumab and assessed the association between chronological NLR changes throughout chemotherapy and tumor response to nivolumab. Changes in NLR during pretreatment chemotherapy might predict tumor response to nivolumab monotherapy in patients with advanced GC.  相似文献   
35.
目的:探讨醛-酮还原酶家族7成员A3(AKR7A3)在肺腺癌中的异常表达及与临床病理特征的关系,并探究其临床意义。方法:采用生物信息学数据库分析、免疫组化、Western Blot、Real-time PCR等方法对肺腺癌组织及不同细胞中AKR7A3的表达进行检测与分析。结果:Oncomine数据库分析结果显示,在肺腺癌中,AKR7A3的表达普遍高于正常肺组织,分别为正常肺组织的1.811倍(P=0.022)、1.356倍(P<0.01)、1.413倍(P=0.002)。Kaplan-Meier Plotter数据库分析结果显示,AKR7A3高表达的患者较低表达的患者生存时间缩短,差异具有统计学意义(P=0.003 7)。免疫组化染色显示肺腺癌组织中AKR7A3的表达较癌旁增高,在与临床病理特征的相关性分析中,发现其与肿瘤分化程度(P<0.01)、淋巴结转移情况(P=0.029)以及TNM分期(P<0.01)相关,且会造成患者生存时间缩短(P=0.031)。Cox多因素分析表明AKR7A3可能是影响肺腺癌患者预后的独立危险因素(P=0.012)。Western Blot及Real-time PCR实验提示不同肺腺癌细胞中AKR7A3蛋白及mRNA表达普遍增高。结论:AKR7A3在肺腺癌中表达增高,对预后有不良影响,有促进肿瘤发生发展的作用。  相似文献   
36.
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   
37.
目的观察至阳八阵穴隔附子饼灸治疗脾胃气虚型糖尿病胃轻瘫的疗效及对胃泌素(GAS)、胃动素(MTL)和血管活性肠肽(VIP)水平的影响。方法86例脾胃气虚型糖尿病胃轻瘫患者随机分为对照组和治疗组,每组43例。治疗组给予至阳八阵穴隔附子饼灸;对照组口服枸橼酸莫沙必利片。治疗12周后观察胃轻瘫主要症状指数量表症状积分改善情况、胃排空率及血清GAS、MTL、VIP水平。结果治疗组治疗后在胃轻瘫主要症状指数量表症状积分及胃排空率方面明显高于对照组,差异均有统计学意义(P<0.05)。治疗组治疗后血清GAS、MTL水平明显高于对照组,血清VIP水平明显低于对照组,差异均有统计学意义(P<0.05)。治疗组总有效率为90.7%,明显高于对照组的72.1%(P<0.05)。结论采用至阳八阵穴隔附子饼灸能快速促进糖尿病胃轻瘫患者胃功能的恢复,改善症状和体征,其作用机制可能与升高患者血清GAS和MTL水平,降低VIP水平有关。  相似文献   
38.
BackgroundThe association of treatment volume and oncological outcome of rectal cancer patients undergoing multidisciplinary treatment is subject of an ongoing debate. Prospective data on long-term local control and overall survival (OS) are not available so far. This study investigated the long-term influence of hospital and surgeon volume on local recurrence (LR) and OS in patients with locally advanced rectal cancers.MethodsIn a post-hoc analysis of the randomized phase III CAO/ARO/AIO-94 trial after a follow-up of more than 10 years, 799 patients with stage II/III rectal cancers were evaluated. LR-rates and OS were stratified by hospital recruitment volume (≤20 vs. 21–90 vs. >90 patients) and by surgeon volume (≤10 vs. 11–50 vs. >50 procedures).ResultsPatients treated in high-volume hospitals had a longer OS than those treated in hospitals with medium or low treatment volume (p = 0.03). The surgeon volume was adversely associated with LR (p = 0.01) but had no influence on overall survival. The positive effect of neoadjuvant chemoradiation (CRT) on local control was the strongest in patients being operated by medium-volume surgeons, less in patients being operated by high-volume surgeons and missing in those being operated by low-volume surgeons.ConclusionsPatients with locally advanced rectal cancers might benefit from treatment in specialized high-volume hospitals. In particular, the surgeon volume had significant influence on long-term local tumour control. The effect of neoadjuvant CRT on local tumour control may likewise depend on the surgeon volume.  相似文献   
39.
BackgroundDetails of perioperative outcomes and survival after gastric cancer surgery in prior transplant recipients have received minimal research attention.MethodsWe performed an observational cohort study using the database of 20,147 gastric cancer patients who underwent gastrectomy at a single gastric cancer center in Korea. Forty-one solid organ recipients [kidney (n = 35), liver (n = 5), or heart (n = 1)] were matched with 205 controls using propensity score matching.ResultsOperation time, blood loss, and postoperative pain were similar between groups. Short-term complication rates were similar between transplantation and control groups (22.0% vs. 20.1%, P = 0.777). Transplantation group patients with stage 1 gastric cancer experienced no recurrence, while those with stage 2/3 cancer had significantly higher recurrence risk compared to the controls (P = 0.049). For patients with stage 1 cancer, the transplantation group had a significantly higher rate of non-gastric cancer-related deaths compared to the controls (19.2% vs. 1.4%, P = 0.001). For those with stage 2/3 cancer, significantly lower proportion of the transplantation group received adjuvant chemotherapy compared to the control group (26.7% vs. 80.3%, P < 0.001). The transplantation group had a higher (albeit not statistically significant) rate of gastric cancer-related deaths compared to the controls (40.0% vs. 18.0%, P = 0.087).ConclusionTransplant recipients and non-transplant recipients exhibited similar perioperative and short-term outcomes after gastric cancer surgery. From long-term outcome analyses, we suggest active surveillance for non-gastric cancer-related deaths in patients with early gastric cancer, as well as strict oncologic care in patients with advanced cancer, as effective strategies for transplant recipients.  相似文献   
40.
随着对胃食管反流病研究的深入,大脑和食管感觉及胃排空的相互作用越来越受到重视,功能磁共振成像技术,有助于进一步了解胃食管反流病的发病机制。  相似文献   
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