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Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
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目的 分析比较容积调强弧形治疗(VMAT)与固定野调强放疗(F_IMRT)、电子束联合VMAT (E&VMAT)技术在乳腺癌改良根治术后放疗中的剂量学差异,为临床选择治疗方案提供参考。方法 随机选择乳腺癌改良根治术后放疗的左乳腺癌患者 10例,靶区包括患侧胸壁和锁骨上淋巴引流区,处方剂量43.5Gy (2.9 Gy/次)。基于Pinnacle3计划系统为每位患者分别设计VMAT、F_IMRT、E&VMAT (胸壁靶区部分电子束照射、锁骨上区部分VMAT照射)计划。对比评价靶区剂量分布适形度与均匀性、危及器官受量以及治疗实施时间。结果 VMAT计划能改善靶区剂量分布,靶区剂量适形指数和均匀性指数均优于F_IMRT和E&VMAT计划(均 P<0.05)。VMAT计划患侧肺平均剂量 、V30Gy、V20Gy、V10Gy均优于F_IMRT和E&VMAT计划(均 P<0.05)。VMAT计划患侧 肺V5Gy优于F_IMRT计划(P<0.05),与E&VMAT计划 的V5Gy相近(P>0.05)。VMAT计划的心脏、健侧乳腺、健侧肺均能满足临床剂量限制要求。VMAT、F_IMRT、E&VMAT计划的治疗时间分别为(326±27)、(1082±169)、(562±48) s。结论 与F_IMRT和E&VMAT计划相比,VMAT计划质量更优,治疗时间更短,具有较高的临床应用价值。  相似文献   
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Purpose

Suicide is a leading cause of death in patients with schizophrenia. This nationwide cohort study investigated the incidence of each suicide method in patients with schizophrenia compared with the general population.

Methods

In total, records of 174,039 patients with schizophrenia were obtained from the National Health Insurance Research Database in Taiwan from 2001 to 2016. This schizophrenia cohort was linked with the national mortality database, and 26,926 patients died during this follow-up period. Of the deceased, 3033 had died by suicide. Univariate Cox regression was used to estimate the demographic variables associated with suicide. We estimated the difference in the proportion of each suicide method used in patients with schizophrenia compared with the general population. The incidence and standardized mortality ratio (SMR) of each suicide method were calculated and stratified based on sex.

Results

Patients aged 25–34 years exhibited the highest suicide risk. Compared with the general population, patients with schizophrenia were more likely to commit suicide by jumping and drowning and less likely to use charcoal-burning and hanging. Women showed a higher incidence of suicide by drowning and jumping than did men. Comorbidity with substance use disorders (SUDs) was associated with a high suicide SMR (26.9, 95% confidence interval [CI] = 23.4–28.9), particularly for suicide by jumping (61.2, 95% CI = 48.3–76.3).

Conclusions

Patients with schizophrenia had higher suicide rates for all methods than did the general population. Suicide method differed based on sex. Patients with SUDs exhibit a high SMR for each suicide method and warrant intensive clinical attention.

  相似文献   
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放射治疗是癌症的主要治疗手段之一,以机器学习为代表的人工智能飞速发展,可应用于放射治疗临床实践的各个环节,包括临床决策支持、自动勾画靶区、预测疗效和副反应等,提高准确性与效率。尽管面临着结构化数据缺乏、模型可解释性差等挑战,机器学习在放射治疗中的应用将日趋深刻而广泛。本文从机器学习简介、在放射治疗中的临床应用研究进展和挑战与解决之道等3个方面展开综述。  相似文献   
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