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Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
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目的:建立本院幽门螺杆菌根除方案的药物利用评价(Drug use evaluation,DUE)标准,为合理治疗幽门螺杆菌提供依据。方法:根据建立的幽门螺杆菌(Hp)根除治疗方案的DUE标准,采用回顾性方法,对本院2019年1月~12月行Hp检测的患者,从用药指征、用药过程、用药结果进行评价与分析。结果:用药指征合理率为99.8%;用药过程中有73.9%的药物方案选择合理,用法用量合理率为78.0%,治疗疗程合理率为98.3%;用药结果合理率为12.8%。结论:依照所建立的Hp根除方案的药物利用评价标准,并对本院Hp根除治疗方案进行评估,可发现治疗过程中的缺陷,为规范幽门螺旋杆菌的药物治疗提供参考。  相似文献   
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Invasive organisms pose a global threat and are exceptionally difficult to eradicate after they become abundant in their new habitats. We report a successful multitactic strategy for combating the pink bollworm (Pectinophora gossypiella), one of the world’s most invasive pests. A coordinated program in the southwestern United States and northern Mexico included releases of billions of sterile pink bollworm moths from airplanes and planting of cotton engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). An analysis of computer simulations and 21 y of field data from Arizona demonstrate that the transgenic Bt cotton and sterile insect releases interacted synergistically to reduce the pest’s population size. In Arizona, the program started in 2006 and decreased the pest’s estimated statewide population size from over 2 billion in 2005 to zero in 2013. Complementary regional efforts eradicated this pest throughout the cotton-growing areas of the continental United States and northern Mexico a century after it had invaded both countries. The removal of this pest saved farmers in the United States $192 million from 2014 to 2019. It also eliminated the environmental and safety hazards associated with insecticide sprays that had previously targeted the pink bollworm and facilitated an 82% reduction in insecticides used against all cotton pests in Arizona. The economic and social benefits achieved demonstrate the advantages of using agricultural biotechnology in concert with classical pest control tactics.

Invasive life forms pose a major global threat and are especially difficult to eradicate after they become widespread and abundant in their new habitats (14). The pink bollworm (Pectinophora gossypiella), one of the world’s most invasive insects, is a voracious lepidopteran pest of cotton that was first detected in the United States in 1917 (58). For most of the past century, it was particularly destructive in the southwestern United States, including Arizona, where its larvae fed almost exclusively on cotton, consuming the seeds inside bolls and disrupting lint production (6, 8). In 1969, its peak seasonal density at an Arizona study site was 1.8 million larvae per hectare (ha), which translates to over 200 billion larvae in the 126,000 ha of cotton planted statewide that year (9, 10). In 1990, this pest cost Arizona cotton growers $48 million, including $32 million damage to cotton despite $16 million spent for insecticides sprayed to control it (11). In several field trials, mass releases of sterile pink bollworm moths to mate with wild moths reduced progeny production somewhat, yet did not suppress established populations because the sterile moths did not sufficiently outnumber the wild moths (6, 1214).Pink bollworm control was revolutionized in 1996 by the introduction of cotton genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). Bt proteins kill some major insect pests yet are not toxic to most nontarget organisms, including people and many beneficial insects (1517). Transgenic Bt cotton helped to reduce the total annual cost of pink bollworm damage and insecticide treatments to $32 million in the United States (18). Although Bt cotton kills essentially 100% of susceptible pink bollworm larvae (1921), this pest rapidly evolved resistance to Bt proteins in laboratory selection experiments in Arizona and in Bt cotton fields in India (2024). To delay the evolution of resistance to Bt cotton, farmers in Arizona planted “refuges” of non-Bt cotton that yielded abundant susceptible moths to mate with the rare resistant moths emerging from Bt cotton (Fig. 1A). The refuge strategy, which has been mandated in the United States and many other countries, but was not adopted widely by farmers in India, helped preserve pink bollworm susceptibility to Bt cotton in Arizona from 1996 to 2005 (24).Open in a separate windowFig. 1.Management strategies. (A) The refuge strategy is the primary approach adopted worldwide to delay the evolution of pest resistance to Bt crops and was used in Arizona from 1996 to 2005. Refuges of non-Bt cotton planted near Bt cotton produce abundant susceptible moths (blue) to mate with the rare resistant moths (red) emerging from Bt cotton. If the inheritance of resistance to Bt cotton is recessive, as in pink bollworm, the heterozygous offspring from matings between resistant and susceptible moths die when they feed on Bt cotton bolls as larvae (24). (B) Bt cotton and sterile moth releases were used together in Arizona from 2006 to 2014 as part of a multitactic program to eradicate the pink bollworm. Susceptible sterile moths (brown) were released from airplanes to mate with the rare resistant moths emerging from Bt cotton. The few progeny produced by such matings (48) are expected to be heterozygous for resistance and to die when they feed on Bt cotton bolls as larvae.As part of a coordinated, multitactic effort to eradicate the pink bollworm from the southwestern United States and northern Mexico, a new strategy largely replacing refuges with mass releases of sterile pink bollworm moths was initiated in Arizona during 2006 (Fig. 1B; 2427). To enable this novel strategy, the US Environmental Protection Agency granted a special exemption from the refuge requirement, which allowed Arizona cotton growers to plant up to 100% of their cotton with Bt cotton (28). We previously reported data from 1998 to 2009 showing that this innovative strategy sustained susceptibility of pink bollworm to Bt cotton while reducing the pest’s population density (25). Here, to test the idea of eradicating pink bollworm with the combination of Bt cotton and sterile releases, we conducted computer simulations and analyzed field data collected in Arizona from 1998 to 2018.  相似文献   
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目的探讨含呋喃唑酮、四环素的四联疗法在补救根除幽门螺杆菌(Helicobacter pylori,Hp)治疗中辅助应用不同疗程双歧杆菌四联活菌片对根除率及不良反应的影响。方法选取2016年12月至2019年5月于华北理工大学附属开滦总医院消化内科门诊就诊患者348例进行前瞻性研究,均为初次根除Hp失败的慢性胃炎患者,利用Excel随机分组方法分为A、B、C组,A组(116例)给予14 d艾普拉唑、果胶铋、呋喃唑酮、四环素方案治疗;B组(116例)在A组方案基础上同时服用14d双歧杆菌四联活菌片;C组(116例)在A组方案治疗第二周开始同时服用7 d双歧杆菌四联活菌片。根除治疗结束4周后复查14C-尿素呼气试验,比较3组的Hp根除率及不良反应发生率。结果3组按意向性治疗分析根除率分别为80.2%、84.5%和82.3%,按符合方案分析根除率分别为88.6%、90.7%和89.7%,3组两种分析方法比较,差异均无统计学意义(按意向性治疗分析:χ^2=0.755P=0.685,按符合方案分析:χ^2=0.271P=0.873);3组不良反应发生率分别为16.4%、6.3%和7.3%,差异有统计学意义(χ^2=7.561,P=0.023),且B组显著低于A组(χ^2=5.570,P=0.017),差异有统计学意义,但C组与A组比较差异无统计学意义(χ^2=4.362,P=0.037)。结论14 d双歧杆菌四联活菌片辅助含呋喃唑酮、四环素的四联疗法补救根除Hp可以显著降低不良反应,但双歧杆菌四联活菌片不能显著提高Hp根除率。  相似文献   
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