虽然妊娠期合并恶性肿瘤较为罕见,但随着女性妊娠期年龄的增大、头颈部癌症(head and neck cancer,HNC)患者的年轻化,妊娠期合并HNC的发病率略有增加。然而,目前临床尚缺乏关于妊娠期HNC的规范化诊疗标准。本研究通过系统检索PubMed数据...虽然妊娠期合并恶性肿瘤较为罕见,但随着女性妊娠期年龄的增大、头颈部癌症(head and neck cancer,HNC)患者的年轻化,妊娠期合并HNC的发病率略有增加。然而,目前临床尚缺乏关于妊娠期HNC的规范化诊疗标准。本研究通过系统检索PubMed数据库,评估孕妇(含围产期)患HNC的频率、肿瘤类型、相关因素和特异性生物标志物,并依据循证医学证据,对妊娠期合并HNC的研究进行综述,以期为临床工作提供指导。展开更多
According to the transversely isotropic theory and weak plane criterion, and considering the mechanical damages due to stress unloading and hydration during drilling, a shale wellbore stability model with the influenc...According to the transversely isotropic theory and weak plane criterion, and considering the mechanical damages due to stress unloading and hydration during drilling, a shale wellbore stability model with the influence of stress unloading and hydration was established using triaxial test and shear test. Then, factors influencing the wellbore stability in shale were analyzed. The results indicate that stress unloading occurs during drilling in shale. The larger the confining pressure and axial stress, the more remarkable weakening of shale strength caused by stress unloading. The stress unloading range is positively correlated with the weakening degree of shale strength. Shale with a higher development degree of bedding is more prone to damage along bedding. In this case, during stress unloading, the synergistic effect of weak structural plane and stress unloading happens, leading to a higher weakening degree of shale strength and poorer mechanical stability, which brings a higher risk of wellbore instability. Fluid tends to invade shale through bedding, promoting the shale hydration. Hydration also can weaken shale mechanical stability, causing the decline of wellbore stability. Influence of stress unloading on collapse pressure of shale mainly occurs at the early stage of drilling, while the influence of hydration on wellbore stability mainly happens at the late stage of drilling. Bedding, stress unloading and hydration jointly affect the wellbore stability in shale. The presented shale wellbore stability model with the influence of stress unloading and hydration considers the influences of the three factors. Field application demonstrates that the prediction results of the model agree with the actual drilling results, verifying the reliability of the model.展开更多
文摘虽然妊娠期合并恶性肿瘤较为罕见,但随着女性妊娠期年龄的增大、头颈部癌症(head and neck cancer,HNC)患者的年轻化,妊娠期合并HNC的发病率略有增加。然而,目前临床尚缺乏关于妊娠期HNC的规范化诊疗标准。本研究通过系统检索PubMed数据库,评估孕妇(含围产期)患HNC的频率、肿瘤类型、相关因素和特异性生物标志物,并依据循证医学证据,对妊娠期合并HNC的研究进行综述,以期为临床工作提供指导。
基金Supported by the National Natural Science Foundation of China(42202194)Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(2020CX040102).
文摘According to the transversely isotropic theory and weak plane criterion, and considering the mechanical damages due to stress unloading and hydration during drilling, a shale wellbore stability model with the influence of stress unloading and hydration was established using triaxial test and shear test. Then, factors influencing the wellbore stability in shale were analyzed. The results indicate that stress unloading occurs during drilling in shale. The larger the confining pressure and axial stress, the more remarkable weakening of shale strength caused by stress unloading. The stress unloading range is positively correlated with the weakening degree of shale strength. Shale with a higher development degree of bedding is more prone to damage along bedding. In this case, during stress unloading, the synergistic effect of weak structural plane and stress unloading happens, leading to a higher weakening degree of shale strength and poorer mechanical stability, which brings a higher risk of wellbore instability. Fluid tends to invade shale through bedding, promoting the shale hydration. Hydration also can weaken shale mechanical stability, causing the decline of wellbore stability. Influence of stress unloading on collapse pressure of shale mainly occurs at the early stage of drilling, while the influence of hydration on wellbore stability mainly happens at the late stage of drilling. Bedding, stress unloading and hydration jointly affect the wellbore stability in shale. The presented shale wellbore stability model with the influence of stress unloading and hydration considers the influences of the three factors. Field application demonstrates that the prediction results of the model agree with the actual drilling results, verifying the reliability of the model.
