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1.
Over the last 40 years, the incidence and prevalence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have continued to increase. Compared to other epithelial neoplasms in the same organ, GEP-NENs exhibit indolent biological behavior, resulting in more chances to undergo surgery. However, the role of surgery in high-grade or advanced GEP-NENs is still controversial. Surgery is associated with survival improvement of well-differentiated high-grade GEP-NENs, whereas poorly differentiated GEP-NENs that may benefit from resection require careful selection based on Ki67 and other tissue biomarkers. Additionally, surgery also plays an important role in locally advanced and metastatic disease. For locally advanced GEP-NENs, isolated major vascular involvement is no longer an absolute contraindication. In the setting of metastatic GEP-NENs, radical intended surgery is recommended for patients with low-grade and resectable metastases. For unresectable metastatic disease, a variety of surgical approaches, including cytoreduction of liver metastasis, liver transplantation, and surgery after neoadjuvant treatment, show survival benefits. Primary tumor resection in GEP-NENs with unresectable metastatic disease is associated with symptom control, prolonged survival, and improved sensitivity toward systemic therapies. Although there is no established neoadjuvant or adjuvant strategy, increasing attention has been given to this emerging research area. Some studies have reported that neoadjuvant therapy effectively reduces tumor burden, improves the effectiveness of subsequent surgery, and decreases surgical complications.  相似文献   
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幽门螺杆菌(HP)是革兰阴性微需氧的螺旋样杆菌,主要通过口-口途径在人-人之间感染传播。HP的发现加深了人类对慢性感染、炎症和癌症之间关系的认识。其特定的螺旋形体型、鞭毛及动力、尿素酶和黏附素活性,以及细胞毒素基因A(cagA)、空泡细胞毒素基因A(vacA)等是影响HP感染研究较多的相关致病因素。HP感染在胃癌的发生、发展中可能具有重要作用,但尚未确切证实HP感染是导致胃癌的主因。文章概述了HP感染相关致病因素的研究进展。  相似文献   
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First-line chemotherapy for advanced/metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric/gastroesophageal junction cancer (GC/GEJC) has poor median overall survival (OS; <1 year). We report efficacy and safety results from Chinese patients in the phase III global CheckMate 649 study of nivolumab plus chemotherapy vs chemotherapy for the first-line treatment of GC/GEJC/esophageal adenocarcinoma (EAC). Chinese patients with previously untreated advanced or metastatic GC/GEJC/EAC were randomized to receive nivolumab (360 mg Q3W or 240 mg Q2W) plus chemotherapy (XELOX [capecitabine and oxaliplatin] Q3W or FOLFOX [oxaliplatin, leucovorin and 5-fluorouracil] Q2W), nivolumab plus ipilimumab (not reported) or chemotherapy alone. OS, blinded independent central review-assessed progression-free survival (PFS), objective response rate (ORR), duration of response (DOR) and safety are reported. Of 1581 patients enrolled and randomized, 208 were Chinese. In these patients, nivolumab plus chemotherapy resulted in clinically meaningful improvement in median OS (14.3 vs 10.2 months; HR 0.61 [95% CI: 0.44-0.85]), median PFS (8.3 vs 5.6 months; HR 0.57 [95% CI: 0.40-0.80]), ORR (66% vs 45%) and median DOR (12.2 vs 5.6 months) vs chemotherapy, respectively. The safety profile was acceptable, with no new safety signals observed. Consistent with results from the global primary analysis of CheckMate 649, nivolumab plus chemotherapy demonstrated a clinically meaningful improvement in OS and PFS and higher response rate vs chemotherapy and an acceptable safety profile in Chinese patients. Nivolumab plus chemotherapy represents a new standard first-line treatment for Chinese patients with non-HER2-positive advanced GC/GEJC/EAC.  相似文献   
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Journal of Digital Imaging - Scoliosis is a condition of abnormal lateral spinal curvature affecting an estimated 2 to 3% of the US population, or seven million people. The Cobb angle is the...  相似文献   
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Background

Programmed death ligand-1 (PD-L1) is a potential predictive biomarker for immunotherapy in several malignancies. However, the expression level and clinical significance of PD-L1 in von Hippel–Lindau (VHL)-associated hereditary clear-cell renal cell carcinoma (ccRCC) remain unclear.

Patients and Methods

Surgical specimens were recruited from 129 patients with sporadic ccRCC and 26 patients with VHL-associated hereditary ccRCC. The PD-L1 expression level was assessed using immunohistochemistry. Correlations between PD-L1 expression and clinicopathological features were analyzed.

Results

In sporadic ccRCC, the positive expression rate of PD-L1 was 47.3% (61/129). Positive PD-L1 expression was correlated with advanced tumor T stage (P = .011), higher Fuhrman nuclear grade (P = .022), poor disease-free survival (P = .037), and sex (P = .025). In the VHL-associated hereditary ccRCC, positive PD-L1 expression rate was 34.6% (9/26), lower than that in sporadic ccRCC. Positive PD-L1 was correlated with higher Fuhrman nuclear grade (P = .008), but not with sex, age, tumor stage, or the onset age of VHL-associated tumors.

Conclusion

Positive PD-L1 expression was correlated with the aggressive clinicopathological features in sporadic and VHL-associated hereditary ccRCC. Whether PD-L1 expression level in ccRCC is related to the effectiveness of programmed death-1/PD-L1 checkpoint inhibitor immunotherapy needs to be further investigated.  相似文献   
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目的 探讨肿瘤医院护士工作家庭冲突、应对方式与职业倦怠的现状,并探讨三者之间的相关性。方法 采用便利抽样于2020年1月-2月选取天津市某肿瘤医院护士222名作为研究对象,采用一般资料调查表、工作家庭冲突量表、简易应对方式量表和职业倦怠量表分析肿瘤医院护士的工作家庭冲突、应对方式和职业倦怠的相关性。结果调查研究对象工作家庭冲突总分为50.17±12.89分;积极应对维度均分为2.03±0.57分,消极应对维度均分为1.72±0.83分;职业倦怠均分为3.17±0.98分。工作-家庭冲突各维度均与职业倦怠成正相关(r=0.618~0.697,P<0.01);积极应对维度与职业倦怠成负相关(r=-0.248,P<0.01);消极应对维度与职业倦怠成正相关(r=0.319,P<0.01)。多元线性回归分析显示工作家庭冲突的时间维度、压力维度、行为维度和消极应对方式是肿瘤医院护士的职业倦怠的影响因素(P<0.05),可独立解释肿瘤专科护士职业倦怠49.2%的变异。结论 肿瘤医院护士职业倦怠程度较严重,护理管理者应采取相关措施降低工作家庭冲突水平,帮助其采取积极应对方式处理问题,从而降低职业倦怠感,提高工作满意度。  相似文献   
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目的:探讨RNA结合蛋白QKI-5在肾癌中的生物学功能。方法:应用以慢病毒为载体的过表达技术观察过表达QKI-5对肾癌细胞增殖作用的影响及对细胞周期的影响。结果:过表达QKI-5能够抑制肾癌细胞株786-O和A-498细胞的增殖能力、克隆形成能力;流式细胞术结果显示:过表达QKI-5使786-O和A-498细胞产生G1期阻滞,而这种阻滞与周期相关蛋白Cyclin D1表达降低及p21、p27表达增高有关。结论:QKI-5在肾癌中发挥着抑癌基因的功能,可以抑制肾癌细胞增殖,并使细胞周期阻滞在G1期。  相似文献   
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