API RP 7G-2标准、NS-2标准是钻探设备制造和检验中常用的两个标准,它们各自具有不同的特点和应用范围,了解这些差异对于确保钻探设备的安全性和可靠性至关重要。通过对二者的深入分析,识别其在钻柱常用构件方面的差异,探讨这些不同对...API RP 7G-2标准、NS-2标准是钻探设备制造和检验中常用的两个标准,它们各自具有不同的特点和应用范围,了解这些差异对于确保钻探设备的安全性和可靠性至关重要。通过对二者的深入分析,识别其在钻柱常用构件方面的差异,探讨这些不同对钻具作业整体表现的潜在影响,为同领域的技术进步与创新提供方向。展开更多
Since Isaacson and Wright first reported on the extranodal marginal zone B-cell lymphoma of the stomach in 1983,following studies have clarified many aspects of this disease.We now know that the stomach is the most af...Since Isaacson and Wright first reported on the extranodal marginal zone B-cell lymphoma of the stomach in 1983,following studies have clarified many aspects of this disease.We now know that the stomach is the most affected organ by this disease,and approximately90% of gastric mucosa-associated lymphoid tissue(MALT) lymphomas are related to Helicobacter pylori(H.pylori) infection.This implies that approximately 10% of gastric MALT lymphomas occur independent of H.pylori infection.The pathogenesis of these H.pylori-negative gastric MALT lymphomas remains unclear.To date,there have been several speculations.One possibility is that genetic alterations result in nuclear factor-kappa B(NF-κB) activation.Among these alterations,t(11;18)(q21;q21) is more frequently observed in H.pylori-negative gastric MALT lymphomas,and such translocation results in the synthesis of fusion protein API2-MALT1,which causes canonical and noncanonical NF-κB activation.Another possibility is infection with bacteria other than H.pylori.This could explain why H.pylori eradication therapy can cure some proportions of H.pylori-negative gastric MALT lymphoma patients,although the bacteria responsible for MALT lymphomagenesis are yet to be defined.Recent advances in endoscopy suggest magnifying endoscopy with narrow band imaging as a useful tool for both detecting gastric MALT lymphoma lesions and judging the response to treatment.A certain proportion of H.pylori-negative gastric MALT lymphoma patients respond to eradication therapy; hence,H.pylori eradication therapy could be considered as a first-line treatment for gastric MALT lymphomas regardless of their H.pylori infection status.展开更多
文摘Since Isaacson and Wright first reported on the extranodal marginal zone B-cell lymphoma of the stomach in 1983,following studies have clarified many aspects of this disease.We now know that the stomach is the most affected organ by this disease,and approximately90% of gastric mucosa-associated lymphoid tissue(MALT) lymphomas are related to Helicobacter pylori(H.pylori) infection.This implies that approximately 10% of gastric MALT lymphomas occur independent of H.pylori infection.The pathogenesis of these H.pylori-negative gastric MALT lymphomas remains unclear.To date,there have been several speculations.One possibility is that genetic alterations result in nuclear factor-kappa B(NF-κB) activation.Among these alterations,t(11;18)(q21;q21) is more frequently observed in H.pylori-negative gastric MALT lymphomas,and such translocation results in the synthesis of fusion protein API2-MALT1,which causes canonical and noncanonical NF-κB activation.Another possibility is infection with bacteria other than H.pylori.This could explain why H.pylori eradication therapy can cure some proportions of H.pylori-negative gastric MALT lymphoma patients,although the bacteria responsible for MALT lymphomagenesis are yet to be defined.Recent advances in endoscopy suggest magnifying endoscopy with narrow band imaging as a useful tool for both detecting gastric MALT lymphoma lesions and judging the response to treatment.A certain proportion of H.pylori-negative gastric MALT lymphoma patients respond to eradication therapy; hence,H.pylori eradication therapy could be considered as a first-line treatment for gastric MALT lymphomas regardless of their H.pylori infection status.
