The Diakha gold deposit is located in the southeastern margin of the highly prospective/productive Paleoproterozoic( Birimian) Kédougou-Kéniéba Inlier. Gold mineralization is closely associated with a n...The Diakha gold deposit is located in the southeastern margin of the highly prospective/productive Paleoproterozoic( Birimian) Kédougou-Kéniéba Inlier. Gold mineralization is closely associated with a narrow,sub-vertical,NE-trending shear corridor. The corridor is to the east of a sinistrally reactivated D1 west-dipping fault,which emanated from SMSZ( D2 reverse-sinistral regional structure). The mineralization is hosted by fine-grained sandstone and breccias units associated with a moderate to strong hydrothermal alteration,which is dominated by albitization,carbonization,silicification,hematization,and chloritization. Diakha field data and laboratory analysis suggest the existence of two main stages of hydrothermal mineralization,namely stage I and stage II. Stage I is of a breccias type of mineralization and represents the major gold bearing stage. It isassociated with hematite + calcite + ankerite/dolomite and quartz pervasive alteration,controlled by the predominantly brittle-ductile NNE to NE-shearing structures of the main deformation event D2. Stage II is represented by the second minor hydrothermal episode,showing local quartz-tourmaline and tremolite alteration which is structurally controlled by the dipping S3 cleavage formed during D3 deformation. Petrographic and microthermometric studies of fluid inclusions from quartz veins reveal the presence of early dominant carbonic CO2-pure and aqueous-carbonic CO2-rich( LCO2+ VCO2± H2 O) in stage I. The exclusively aqueous H2 O + Na Cl ± CO2 fluid inclusions( L-type) are observed in stage II. Interpretation shows that the ore-forming fluids originated from a homogeneous H2 O-CO2 fluid during phase separation,with trapping temperatures of 250℃ to 280℃ and low salinity( < 6 wt % Na Cl equiv),indicating an estimated trapping pressure for the deposit between 610 to 800 bars.展开更多
目的评估数字化三维打印前方牵引装置联合上颌快速扩缩弓在矫治替牙期骨性Ⅲ类患者中的骨效应、牙效应、软组织侧貌及气道变化。方法选取2018—2023年收治的22例伴有上颌发育不足的骨性Ⅲ类替牙(牙合)患者(平均年龄(11.33±0.88)岁,...目的评估数字化三维打印前方牵引装置联合上颌快速扩缩弓在矫治替牙期骨性Ⅲ类患者中的骨效应、牙效应、软组织侧貌及气道变化。方法选取2018—2023年收治的22例伴有上颌发育不足的骨性Ⅲ类替牙(牙合)患者(平均年龄(11.33±0.88)岁,男9例,女13例)。使用数字化3D打印前方牵引装置进行治疗,同时联合上颌快速扩弓及缩弓矫治。所有患者治疗前后均进行锥形束CT扫描,评估治疗前后的骨性、牙性、软组织及上气道的矫治效果。结果治疗后,硬组织测量指标SNA、ANB、Wits值、Co-A、Co-Gn均明显增加,差异有统计学意义,而SNB、FMA、Occ plane to FH角、Y轴角无统计学意义变化。U1-SN有统计学意义的增加,而U1-NA变化无统计学意义。软组织上唇距E线距离改善,差异有统计学意义,鼻唇角未发生统计学意义的变化。上气道腭后区容积显著增加。结论数字化3D打印前方牵引装置联合上颌快速扩缩弓可以促进上颌发育,抑制下颌发育,基本维持患者的垂直向变化,改善骨性Ⅲ类错(牙合)畸形和侧貌,上气道腭后区容积也得到明显改善。展开更多
目的正畸正颌是目前治疗严重骨性Ⅲ类错牙合最为有效的手段,但其长期治疗效果存在争议。文章对正畸正颌联合矫治严重骨性Ⅲ类错牙合畸形硬组织的长期稳定性进行系统评价。方法全面检索Cochrane Central Register of Controlled Trials、...目的正畸正颌是目前治疗严重骨性Ⅲ类错牙合最为有效的手段,但其长期治疗效果存在争议。文章对正畸正颌联合矫治严重骨性Ⅲ类错牙合畸形硬组织的长期稳定性进行系统评价。方法全面检索Cochrane Central Register of Controlled Trials、Cochrane Library、Medline(1950-2014)、EMBASE(1980-2014)等外文数据库以及中国生物医学文献数据库、中国期刊全文数据库、中文科技期刊数据库、万方数据库等中文数据库,手工检索相关会议论文及未发表的灰色文献中符合要求的随机对照试验(randomized controlled trial,RCT)、半随机对照试验以及临床病例对照试验(case controlled trial,CCT)文献。对于可合并文献进行Meta分析,对于不可合并研究进行定性描述。结果最终纳入符合要求的5篇外文文献和1篇中文文献。纳入文献所有研究均为CCT,共涉及260例患者。Meta分析结果显示,术后3年内的SNA、SNB、ANB、MP-SN及Y轴角差异均无统计学意义(P>0.05),维持了较好的I骨面型,下颌平面角也保持了相对稳定性。A、B、Pg点及下颌升支角度变化测量方法不同,故无法进行Meta分析,遂进行定性描述。A点及下颌升支角度保持相对稳定,B点及Pg较术后有轻微复发。结论除下颌存在一定复发可能外,正畸联合正颌外科治疗骨性Ⅲ类错牙合治疗效果硬组织总体上保持了长期的稳定性。展开更多
文摘The Diakha gold deposit is located in the southeastern margin of the highly prospective/productive Paleoproterozoic( Birimian) Kédougou-Kéniéba Inlier. Gold mineralization is closely associated with a narrow,sub-vertical,NE-trending shear corridor. The corridor is to the east of a sinistrally reactivated D1 west-dipping fault,which emanated from SMSZ( D2 reverse-sinistral regional structure). The mineralization is hosted by fine-grained sandstone and breccias units associated with a moderate to strong hydrothermal alteration,which is dominated by albitization,carbonization,silicification,hematization,and chloritization. Diakha field data and laboratory analysis suggest the existence of two main stages of hydrothermal mineralization,namely stage I and stage II. Stage I is of a breccias type of mineralization and represents the major gold bearing stage. It isassociated with hematite + calcite + ankerite/dolomite and quartz pervasive alteration,controlled by the predominantly brittle-ductile NNE to NE-shearing structures of the main deformation event D2. Stage II is represented by the second minor hydrothermal episode,showing local quartz-tourmaline and tremolite alteration which is structurally controlled by the dipping S3 cleavage formed during D3 deformation. Petrographic and microthermometric studies of fluid inclusions from quartz veins reveal the presence of early dominant carbonic CO2-pure and aqueous-carbonic CO2-rich( LCO2+ VCO2± H2 O) in stage I. The exclusively aqueous H2 O + Na Cl ± CO2 fluid inclusions( L-type) are observed in stage II. Interpretation shows that the ore-forming fluids originated from a homogeneous H2 O-CO2 fluid during phase separation,with trapping temperatures of 250℃ to 280℃ and low salinity( < 6 wt % Na Cl equiv),indicating an estimated trapping pressure for the deposit between 610 to 800 bars.
文摘目的评估数字化三维打印前方牵引装置联合上颌快速扩缩弓在矫治替牙期骨性Ⅲ类患者中的骨效应、牙效应、软组织侧貌及气道变化。方法选取2018—2023年收治的22例伴有上颌发育不足的骨性Ⅲ类替牙(牙合)患者(平均年龄(11.33±0.88)岁,男9例,女13例)。使用数字化3D打印前方牵引装置进行治疗,同时联合上颌快速扩弓及缩弓矫治。所有患者治疗前后均进行锥形束CT扫描,评估治疗前后的骨性、牙性、软组织及上气道的矫治效果。结果治疗后,硬组织测量指标SNA、ANB、Wits值、Co-A、Co-Gn均明显增加,差异有统计学意义,而SNB、FMA、Occ plane to FH角、Y轴角无统计学意义变化。U1-SN有统计学意义的增加,而U1-NA变化无统计学意义。软组织上唇距E线距离改善,差异有统计学意义,鼻唇角未发生统计学意义的变化。上气道腭后区容积显著增加。结论数字化3D打印前方牵引装置联合上颌快速扩缩弓可以促进上颌发育,抑制下颌发育,基本维持患者的垂直向变化,改善骨性Ⅲ类错(牙合)畸形和侧貌,上气道腭后区容积也得到明显改善。
