AIM:To study how lymph node metastasis(LNM) risk is stratified in undifferentiated-type early gastric cancer(undiff-EGC) dependent on combinations of risk factors.METHODS:Five hundred and sixty-seven cases with undiff...AIM:To study how lymph node metastasis(LNM) risk is stratified in undifferentiated-type early gastric cancer(undiff-EGC) dependent on combinations of risk factors.METHODS:Five hundred and sixty-seven cases with undiff-EGC undergoing gastrectomy with lymphadenectomy were examined retrospectively.Using clinicopathological factors of patient age,location,size,an endoscopic macroscopic tumor form,ulceration,depth,histology,lymphatic involvement(LI) and venous involvement(VI),LNM risk was examined and stratified by conventional statistical analysis and datamining analysis.RESULTS:LNM was positive in 44 of 567 cases(7.8%).Univariate analysis revealed > 2 cm,protrusion,submucosal(sm),mixed type,LI and VI as significant prognostic factors and > 2 cm and LI-positive were independent factors by multivariate analysis.In preoperatively evaluable factors excluding LVI,sm and > 2 cm were independent factors.According to the depth and size,cases were categorized into the low-risk group [m and ≤ 2 cm,0%(LNM incidence)],the moderaterisk group(m and > 2 cm,5.6%; and sm and ≤ 2 cm,6.0%),and the high-risk group(sm and > 2 cm,19.3%).On the other hand,LNM occurred in 1.4% in all LI-negative cases,greatly lower than 28.2% in all LI-positive cases,and LNM incidence was low in LInegative cases even in the moderate- and high-risk groups.CONCLUSION:LNM-related factors in undiff-EGC were depth and size preoperatively while those were LI and size postoperatively.Among these factors,LI was the most significantly correlated factor.展开更多
The bender element testing features its in-plane directivity, which allows using bender elements to measure the shear wave velocities in a wider range of in-plane configurations besides the standard tip-to-tip alignme...The bender element testing features its in-plane directivity, which allows using bender elements to measure the shear wave velocities in a wider range of in-plane configurations besides the standard tip-to-tip alignment. This paper proposed a novel bender element testing technique for measuring the horizontal shear wave velocity of soils, where the bender elements are surface- mounted and the axes of the source and receiver elements are parallel to each other. The preliminary tests performed on model ground of silica sand showed that, by properly determining the travel distance and time of the shear waves, the surface-mounted bender elements can perform as accurately as the conventional "tip-to-tip" configuration. Potentially, the present system provides a promising nondestructive tool for characterizing geomaterials and site conditions both in laboratory and in the fields.展开更多
文摘AIM:To study how lymph node metastasis(LNM) risk is stratified in undifferentiated-type early gastric cancer(undiff-EGC) dependent on combinations of risk factors.METHODS:Five hundred and sixty-seven cases with undiff-EGC undergoing gastrectomy with lymphadenectomy were examined retrospectively.Using clinicopathological factors of patient age,location,size,an endoscopic macroscopic tumor form,ulceration,depth,histology,lymphatic involvement(LI) and venous involvement(VI),LNM risk was examined and stratified by conventional statistical analysis and datamining analysis.RESULTS:LNM was positive in 44 of 567 cases(7.8%).Univariate analysis revealed > 2 cm,protrusion,submucosal(sm),mixed type,LI and VI as significant prognostic factors and > 2 cm and LI-positive were independent factors by multivariate analysis.In preoperatively evaluable factors excluding LVI,sm and > 2 cm were independent factors.According to the depth and size,cases were categorized into the low-risk group [m and ≤ 2 cm,0%(LNM incidence)],the moderaterisk group(m and > 2 cm,5.6%; and sm and ≤ 2 cm,6.0%),and the high-risk group(sm and > 2 cm,19.3%).On the other hand,LNM occurred in 1.4% in all LI-negative cases,greatly lower than 28.2% in all LI-positive cases,and LNM incidence was low in LInegative cases even in the moderate- and high-risk groups.CONCLUSION:LNM-related factors in undiff-EGC were depth and size preoperatively while those were LI and size postoperatively.Among these factors,LI was the most significantly correlated factor.
基金Project supported by the National Basic Research Program (973) of China (No. 2007CB714203)the China Postdoctoral Science Foun-dation (No. 20080430219)partly supported by the Foundation for Seismological Researches, China Earthquake Administration (No. 200808022)
文摘The bender element testing features its in-plane directivity, which allows using bender elements to measure the shear wave velocities in a wider range of in-plane configurations besides the standard tip-to-tip alignment. This paper proposed a novel bender element testing technique for measuring the horizontal shear wave velocity of soils, where the bender elements are surface- mounted and the axes of the source and receiver elements are parallel to each other. The preliminary tests performed on model ground of silica sand showed that, by properly determining the travel distance and time of the shear waves, the surface-mounted bender elements can perform as accurately as the conventional "tip-to-tip" configuration. Potentially, the present system provides a promising nondestructive tool for characterizing geomaterials and site conditions both in laboratory and in the fields.
