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41.
随着人类平均寿命延长,癌症对人类的威胁日益突出,已经成为我国城乡居民的第1位死因。随着病情进展,很多患者除了原发恶性肿瘤外,多数会有其他部位的转移瘤出现,因此选择有效的治疗方法至关重要。体部伽马刀治疗是一种精确的立体定向放疗方法,能够给予肿瘤较高剂量,并较好的保护周围正常组织。大量临床治疗结果显示体部伽马刀治疗肺转移瘤、肝转移瘤和肾上腺转移瘤可获得较高的局控率。本文就体部伽马刀治疗各类转移瘤进行综述。  相似文献   
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BackgroundThe role of self-expandable metallic stents (SEMS) as a bridge to surgery in left-sided malignant colonic obstruction is still debated. Here we assess the morbidity, mortality and long-term oncological outcomes as a bridge to surgery for patients with left-sided malignant colonic obstruction.MethodProspective observational study with retrospective analysis of patients with left-sided malignant colonic obstruction undergoing stenting. April 2006–April 2018. We assessed all patients with intent-to treat and per protocol analyses and long-term follow-up variables.ResultsColonic stent was performed in 117 patients. Technical and clinical success of SEMS placement: 94.4% (111/117), only 4.3% perforation. Elective surgery resection following the strategy of SEMS was performed in 83.8% (98/117). A laparoscopic approach was: 25.6% (30/117); 76.9% in the last two years. Primary anastomosis rate: 92.8% (91/98), without protective stoma in any patients. Anastomotic leakage rate: 8.2% (8/97). Median follow-up: 44.5 months (range 0–109). The intent-to-treat analysis showed overall and disease-free survival rates of 63.3% (74/117) and 58.1% (68/117), and local and distant recurrence rates: 9.4% (11/117) and 58.1% (68/117). In the per protocol analysis, overall and disease-free survival rates: 63.2% (62/98) and 60.2% (58/98), and local and distant recurrence rates: 10.2% (10/98) and 36.7% (36/98). Disease progression was predominantly observed during the first 5 years' follow-up as disease recurrence; after five years' follow-up, 60% of the patients were disease-free.ConclusionsAccording to the results of the study SEMS as a bridge to surgery achieves perioperative results comparable to non-occlusive colonic cancer surgery and does not adversely affect long-term oncological outcomes. Further investigations are needed.  相似文献   
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Cancer stem cells (CSCs) play a decisive role in the development and progression of cancer. To investigate CSCs in Epstein‐Barr virus (EBV)‐associated carcinoma (EBVaGC), we screened previously reported stem cell markers of gastric cancer in EBV‐infected gastric cancer cell lines (TMK1 and NUGC3) and identified CD44v6v9 double positive cells as candidate CSCs. CD44v6/v9+/+ cells were sorted from EBVaGC cell line (SNU719) cells and EBV‐infected TMK1 cells and these cell populations showed high spheroid‐forming ability and tumor formation in SCID mice compared with the respective CD44v6/v9?/? cells. Sphere‐forming ability was dependent on the nuclear factor‐κB (NF‐κB) signaling pathway, which was confirmed by decrease of sphere formation ability under BAY 11‐7082. Small interfering RNA knockdown of latent membrane protein 2A (LMP2A), one of the latent gene products of EBV infection, decreased spheroid formation in SNU719 cells. Transfection of the LMP2A gene increased the sphere‐forming ability of TMK1 cells, which was mediated through NF‐κB signaling. Together, these results indicate that CD44v6v9+/+ cells are CSCs in EBVaGC that are maintained through the LMP2A/NF‐κB pathway. Future studies should investigate CD44v6/v9+/+ cells in normal and neoplastic gastric epithelium to prevent and treat this specific subtype of gastric cancer infected with EBV.  相似文献   
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目的 探讨ArcCHECK系统在食管癌断层治疗旋转照射和固定野照射计划验证中的应用,总结相关经验。方法 对32例不同部位食管癌分别制作Helical旋转照射和Direct固定野照射验证计划,并通过ArcCHECK测量、分析,对比验证结果通过率。分析靶体积与计划验证通过率的相关性。将靶体积较小的治疗验证计划分别放在ArcCHECK模体中心和外周探测点处,分析验证通过率差异。结果 Helical计划验证通过率高于Direct计划(P<0.01),其靶体积与验证通过率的相关系数分别为-0.364和-0.042,P值分别为0.041和0.819。Helical计划采用3%/2mm标准时,高剂量区放在模体中心和外周探测点处测得的通过率不同(P=0.005),后者通过率更高;采用3%/3mm标准时与Direct计划的3%/3m、3%/2mm标准的相近(P均>0.05)。结论 Helical计划验证通过率普遍高于Direct计划,原因可能与ArcCHECK探测器的角度响应以及因更多参考点受到低剂量辐射而未参与计算有关,另外还可能跟Direct计划对断层治疗剂量控制系统要求更高有关。在Helical验证计划中,当采用3%/3mm标准时,靶体积越大,验证时出现较低通过率的可能性增加,但相关系数较低。验证计划的高剂量区位于模体中心或者探测点处都可以实现计划验证,综合考量建议放在模体等中心处。  相似文献   
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BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG.  相似文献   
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Objective: A systematic review reported that coffee consumption would decrease risk of colon cancer in Asian women. But the systematic review arises the issue of duplication, so that a meta-epidemiological study was conducted. Methods: The selection criteria were defined that a prospective cohort follow-up study conducted to evaluate coffee consumption and risk of colon cancer in Asian and showed adjusted relative risk and its 95% confidence interval. In order to conduct meta-analysis, the highest versus lowest method was applied to extract relative risk and its 95% confidence intervals of the highest category. Random effect model was applied if I-squared value was over 50%. Results: After avoiding duplication, 9 cohort data were selected for meta-analysis. The summary relative risk (and their 95% confidence intervals) [I-square value] were 0.90 (95% CI: 0.79-1.03) [0.0%] in men, and 0.64 (95% CI: 0.36-1.15) [65.9%] in women, respectively. Conclusions: The results suggest that coffee consumption is not associated with the risk of colon cancer in Asian men and women. The findings of this study are consistent with the results of two systematic reviews conducted under the same hypothesis and selection criteria. Additional epidemiological studies are needed for the inflection of colon cancer risk as the dose of coffee increases and the difference in the protective effect by sex.  相似文献   
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