[目的]探讨磁共振零回波时间(magnetic resonance zero echo time,MR-ZTE)序列在诊断鼻咽癌颅底骨质侵犯中的诊断价值。[方法]前瞻性入组38例福建省肿瘤医院收治的鼻咽癌初诊患者,进行MR-ZTE和CT检查。对两种成像方法的图像质量进行评...[目的]探讨磁共振零回波时间(magnetic resonance zero echo time,MR-ZTE)序列在诊断鼻咽癌颅底骨质侵犯中的诊断价值。[方法]前瞻性入组38例福建省肿瘤医院收治的鼻咽癌初诊患者,进行MR-ZTE和CT检查。对两种成像方法的图像质量进行评分、计算这两种方法检出颅底骨质结构侵犯例数及侵犯结构数目,分析比较MR-ZTE与CT诊断鼻咽癌颅底骨侵犯率的差异。[结果]MR-ZTE与CT的图像质量评分差异无统计学意义(P>0.05),且两位阅片者之间一致性较高,Kappa值分别为0.95和0.89,P均<0.001。MR-ZTE和CT检出有颅底骨质侵犯的阳性例数分别为31例(81.58%)和32例(84.21%),两者对鼻咽癌颅底骨质侵犯的检出率差异无统计学意义(P>0.05);同时,两种成像技术对颅底单个骨质结构受侵犯的检出率差异均无统计学意义(P>0.05)。[结论]MR-ZTE的图像质量与CT图像质量相当,两者对鼻咽癌颅底骨质侵犯的检出能力一致;MR-ZTE在评价仅骨髓侵犯而无明显骨皮质破坏的早期骨侵犯方面优于CT。因此,MR-ZTE有望作为鼻咽癌磁共振分期扫描的常规序列之一。展开更多
A fully-mechanized coal mining (FMCM) technology capable of filling up the goaf with wastes (including solid wastes) is described. Industrial tests have proved that by using this technology not only can waste be re-us...A fully-mechanized coal mining (FMCM) technology capable of filling up the goaf with wastes (including solid wastes) is described. Industrial tests have proved that by using this technology not only can waste be re-used but also coal resources can be exploited with a higher recovery rate without removing buildings located over the working faces. Two special devices, a hydraulic support and a scraper conveyor, run side-by-side on the same working face to simultaneously realize mining and filling. These are described in detail. The tests allow analysis of rock pressure and ground subsidence when backfilling techniques are employed. These values are compared to those from mining without using backfilling techniques, under the same geological conditions. The concept of equivalent mining height is proposed based on theoretical analysis of rock pressure and ground subsidence. The upper limits of the rock pressure and ground subsidence can be estimated in backfilling mining using this concept along with traditional engineering formulae.展开更多
Based on coal seam geological condition and mining technological characteristic in Jisan Mine, coal seamgeological condition is quantitative evaluated by using fuzzy evaluation with the view of coal mining and coalfac...Based on coal seam geological condition and mining technological characteristic in Jisan Mine, coal seamgeological condition is quantitative evaluated by using fuzzy evaluation with the view of coal mining and coalfaceproduction. The structure and index system of evaluation factor, the membership functions and weights of evaluationfactor, evaluation model and reliability in the coal seam geological conditions are expounded in detail. Eighty-twocoalfaces which will be exploited is classified. All of these have provided a theoretical foundation for the selection ofcoal mining technology and for sustainable development of the coal mine.展开更多
文摘[目的]探讨磁共振零回波时间(magnetic resonance zero echo time,MR-ZTE)序列在诊断鼻咽癌颅底骨质侵犯中的诊断价值。[方法]前瞻性入组38例福建省肿瘤医院收治的鼻咽癌初诊患者,进行MR-ZTE和CT检查。对两种成像方法的图像质量进行评分、计算这两种方法检出颅底骨质结构侵犯例数及侵犯结构数目,分析比较MR-ZTE与CT诊断鼻咽癌颅底骨侵犯率的差异。[结果]MR-ZTE与CT的图像质量评分差异无统计学意义(P>0.05),且两位阅片者之间一致性较高,Kappa值分别为0.95和0.89,P均<0.001。MR-ZTE和CT检出有颅底骨质侵犯的阳性例数分别为31例(81.58%)和32例(84.21%),两者对鼻咽癌颅底骨质侵犯的检出率差异无统计学意义(P>0.05);同时,两种成像技术对颅底单个骨质结构受侵犯的检出率差异均无统计学意义(P>0.05)。[结论]MR-ZTE的图像质量与CT图像质量相当,两者对鼻咽癌颅底骨质侵犯的检出能力一致;MR-ZTE在评价仅骨髓侵犯而无明显骨皮质破坏的早期骨侵犯方面优于CT。因此,MR-ZTE有望作为鼻咽癌磁共振分期扫描的常规序列之一。
基金supports for this work provided by Na-tional basic research program of China (No. 2007CB209400)the National Natural Science Foundation of China (No. 50834004)+1 种基金the National Natural Science Foundation of China (No. 50574090) SR Foundation of China University of Mining & Technology (No. 50634050)
文摘A fully-mechanized coal mining (FMCM) technology capable of filling up the goaf with wastes (including solid wastes) is described. Industrial tests have proved that by using this technology not only can waste be re-used but also coal resources can be exploited with a higher recovery rate without removing buildings located over the working faces. Two special devices, a hydraulic support and a scraper conveyor, run side-by-side on the same working face to simultaneously realize mining and filling. These are described in detail. The tests allow analysis of rock pressure and ground subsidence when backfilling techniques are employed. These values are compared to those from mining without using backfilling techniques, under the same geological conditions. The concept of equivalent mining height is proposed based on theoretical analysis of rock pressure and ground subsidence. The upper limits of the rock pressure and ground subsidence can be estimated in backfilling mining using this concept along with traditional engineering formulae.
文摘Based on coal seam geological condition and mining technological characteristic in Jisan Mine, coal seamgeological condition is quantitative evaluated by using fuzzy evaluation with the view of coal mining and coalfaceproduction. The structure and index system of evaluation factor, the membership functions and weights of evaluationfactor, evaluation model and reliability in the coal seam geological conditions are expounded in detail. Eighty-twocoalfaces which will be exploited is classified. All of these have provided a theoretical foundation for the selection ofcoal mining technology and for sustainable development of the coal mine.
