The molybdenum-nickel deposits in Shuidong District of Nayong County (Guizhou Province, Southwest China) are found mainly in black shale series of Lower Cambrian Niutitang Formation, which is another Mo-Ni-rich regi...The molybdenum-nickel deposits in Shuidong District of Nayong County (Guizhou Province, Southwest China) are found mainly in black shale series of Lower Cambrian Niutitang Formation, which is another Mo-Ni-rich region besides Zunyi District (Guizhou province). Our systematic study on the Mo-Ni deposits in Tangjiaba of Nayong reveals that layered coarse-grained limestones, spherical beaded limestones concretions are hosted at the lower seam of the Mo-Ni deposits. Its strong negative carbon isotope anomaly (the carbon isotope value of the coarse-grained limestones varies from -2.148‰ to 8.223‰) is similar to that in the modern submarine black smoker chimney. The carbon in the coarse-grained limestones from black rock series of Nayong County might be deep source inorganic carbon. The seams, coarse-grained limestones, ore-bearing coarse-grained limestones and the roof and floor of the deposits are characterized by co-variation on the trace element spider diagram, showing good homology. The extraordinary enrichment of Ag, As and Sb resembles hydrothermal sedimentation. Pro-Earth's core elements Se is strongly enriched in Ni-Mo ore-bearing coarse-grained limestones. The ore-bearing rock series has an extremely low Th/U value (0.012-0.19); in the logU-logTh Cartesian Coordinates, the samples of the roof and floor of the deposits and ore-bearing coarse-grained limestones are found in the East Pacific tise; and the samples of coarse-grained limestones are found between the paleo-hydrothermal dedimentary area and the East Pacific tise. The chondrite-normalized rare earth element patterns of the Ni-Mo deposits show LREE enrichment, Ce negative anomaly, and Eu negative anomaly (which is supposed to be influenced by the deep magmatic processes in an extensional environment) resembles the rare earth element distribution patterns of the fluid and its sediments in modern submarine hydrothermal system. It proves that coarse-grained limestones is characterized by typical hydrothermal limestones, being closely related with the genesis of Mo-Ni deposits in Nayong County, which provides new evidence for hydrothermal sedimentary genesis of Mo-Ni deposit and negative carbon anomaly in the basal Cambrian on a global scale.展开更多
Background Thoracic endovascular aortic repair (TEVAR) is an emerging treatment moaality, wnicn nas been rapidly embraced by clinicians treating thoracic aortic disease. However, the clinical manifestations of syste...Background Thoracic endovascular aortic repair (TEVAR) is an emerging treatment moaality, wnicn nas been rapidly embraced by clinicians treating thoracic aortic disease. However, the clinical manifestations of systemic inflammatory response after TEVAR as post-implantation syndrome (PIS) resemble the perioperative infection. This study aimed to evaluate changes and diagnostic value of procalcitonin (PCT) and other traditional inflammatory markers for infections after TEVAR. Methods We conducted a prospective clinical study that enrolled 162 consecutive aortic dissection cases. who underwent TEVAR in our institution between July 2011 and November 2012. The PCT, C-response protein (CRP), erythrocyte sedimentation rate (ESR) and blood routine examination were monitored before the operation and on days 1, 2, 3 and 5 after the operation. The diagnosis of infection was confirmed by the infection control committee with reference to Hospital Acquired Infection Diagnostic Criteria Assessment, released by the Ministry of Health of the People's Republic of China. Results Post endovascular repair of thoracic aorta, PCT changes significantly at different time points (X^2= 13.225, P=0.021), without significant difference between the PIS group and the control group (0.24±0.04 vs.0.26±0.10, P=0.804). PCT values were significantly higher in the first day after TEVAR than the preoperative levels (0.18±0.03 vs. 0.11±0.02, P 〈0.001). Compared with PIS patients, the level of PCT, CRP, White blood cell (WBC) and neutrophil (NEU) in the infection patients elevated significantly (relatively X2=6.062, P=0.048; X2=6.081, P=0.048; X2=11.030, P=0.004; X2=14.632, P=0.001). According to the ROC analysis, the PCT levels in the first day after TEVAR (AUC=0.785, P=0.012) had better predictive values of infection than WBC, NEU CRP and ESR (AUC=0.720, P=0.040; AUC=0.715, P=0.045; AUC=0.663, P=0.274; AUC=0.502, P=0.991). The best predictive index was the changes of PCT between preoperative and postoperative (PCT), which possess AUC as 0.803 (P=0.014). And PCT=0.055 could be considered as an infection diagnosis cutoff value with a sensitivity of 83.3% and specificity 69.0%.展开更多
基金sponsored by the Doctoral Fund of Ministry of Education of China (Grant no.20105201110002)Research Fund of Guizhou Province and Doctoral Programme Fund of Guizhou University
文摘The molybdenum-nickel deposits in Shuidong District of Nayong County (Guizhou Province, Southwest China) are found mainly in black shale series of Lower Cambrian Niutitang Formation, which is another Mo-Ni-rich region besides Zunyi District (Guizhou province). Our systematic study on the Mo-Ni deposits in Tangjiaba of Nayong reveals that layered coarse-grained limestones, spherical beaded limestones concretions are hosted at the lower seam of the Mo-Ni deposits. Its strong negative carbon isotope anomaly (the carbon isotope value of the coarse-grained limestones varies from -2.148‰ to 8.223‰) is similar to that in the modern submarine black smoker chimney. The carbon in the coarse-grained limestones from black rock series of Nayong County might be deep source inorganic carbon. The seams, coarse-grained limestones, ore-bearing coarse-grained limestones and the roof and floor of the deposits are characterized by co-variation on the trace element spider diagram, showing good homology. The extraordinary enrichment of Ag, As and Sb resembles hydrothermal sedimentation. Pro-Earth's core elements Se is strongly enriched in Ni-Mo ore-bearing coarse-grained limestones. The ore-bearing rock series has an extremely low Th/U value (0.012-0.19); in the logU-logTh Cartesian Coordinates, the samples of the roof and floor of the deposits and ore-bearing coarse-grained limestones are found in the East Pacific tise; and the samples of coarse-grained limestones are found between the paleo-hydrothermal dedimentary area and the East Pacific tise. The chondrite-normalized rare earth element patterns of the Ni-Mo deposits show LREE enrichment, Ce negative anomaly, and Eu negative anomaly (which is supposed to be influenced by the deep magmatic processes in an extensional environment) resembles the rare earth element distribution patterns of the fluid and its sediments in modern submarine hydrothermal system. It proves that coarse-grained limestones is characterized by typical hydrothermal limestones, being closely related with the genesis of Mo-Ni deposits in Nayong County, which provides new evidence for hydrothermal sedimentary genesis of Mo-Ni deposit and negative carbon anomaly in the basal Cambrian on a global scale.
文摘Background Thoracic endovascular aortic repair (TEVAR) is an emerging treatment moaality, wnicn nas been rapidly embraced by clinicians treating thoracic aortic disease. However, the clinical manifestations of systemic inflammatory response after TEVAR as post-implantation syndrome (PIS) resemble the perioperative infection. This study aimed to evaluate changes and diagnostic value of procalcitonin (PCT) and other traditional inflammatory markers for infections after TEVAR. Methods We conducted a prospective clinical study that enrolled 162 consecutive aortic dissection cases. who underwent TEVAR in our institution between July 2011 and November 2012. The PCT, C-response protein (CRP), erythrocyte sedimentation rate (ESR) and blood routine examination were monitored before the operation and on days 1, 2, 3 and 5 after the operation. The diagnosis of infection was confirmed by the infection control committee with reference to Hospital Acquired Infection Diagnostic Criteria Assessment, released by the Ministry of Health of the People's Republic of China. Results Post endovascular repair of thoracic aorta, PCT changes significantly at different time points (X^2= 13.225, P=0.021), without significant difference between the PIS group and the control group (0.24±0.04 vs.0.26±0.10, P=0.804). PCT values were significantly higher in the first day after TEVAR than the preoperative levels (0.18±0.03 vs. 0.11±0.02, P 〈0.001). Compared with PIS patients, the level of PCT, CRP, White blood cell (WBC) and neutrophil (NEU) in the infection patients elevated significantly (relatively X2=6.062, P=0.048; X2=6.081, P=0.048; X2=11.030, P=0.004; X2=14.632, P=0.001). According to the ROC analysis, the PCT levels in the first day after TEVAR (AUC=0.785, P=0.012) had better predictive values of infection than WBC, NEU CRP and ESR (AUC=0.720, P=0.040; AUC=0.715, P=0.045; AUC=0.663, P=0.274; AUC=0.502, P=0.991). The best predictive index was the changes of PCT between preoperative and postoperative (PCT), which possess AUC as 0.803 (P=0.014). And PCT=0.055 could be considered as an infection diagnosis cutoff value with a sensitivity of 83.3% and specificity 69.0%.