目的通过选择不同呼气末正压(PEEP)水平,观察对全麻术后患者氧合的影响。方法将全麻术后患者60例分为四组,给予不同水平PEEP,A组:PEEP 0 cm H2O、B组:PEEP 5 cmH2O、C组:PEEP 10 cm H2O,D组:PEEP 15 cm H2O,分别于呼吸机通气前、通气30 ...目的通过选择不同呼气末正压(PEEP)水平,观察对全麻术后患者氧合的影响。方法将全麻术后患者60例分为四组,给予不同水平PEEP,A组:PEEP 0 cm H2O、B组:PEEP 5 cmH2O、C组:PEEP 10 cm H2O,D组:PEEP 15 cm H2O,分别于呼吸机通气前、通气30 min、通气60 min时间点记录氧合指数、MABP值,比较患者氧合指数及MABP变化。结果与A组比较,B组、C组、D组在通气30 min、通气60 min氧合指数改善,有明显差异(P<0.05),B、C、D组间氧合指数比较无明显差异(P>0.05)。与A组比较,D组在通气30 min、通气60 min MABP下降,差异明显(P<0.05),B组、C组MABP无明显差异(P>0.05)。结论不同水平PEEP对全麻术后患者氧合指数均有明显改善,但PEEP 15 cm H2O时可造成MABP明显下降,对术后器官灌注有潜在危害。展开更多
In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 13...In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 135 - 95 m （in composition depth） from ODP Site 1143 （9° 22＇ N, 113° 17＇ E） in the southern South China Sea. The results show that the pollen influx has a distinct change. During 2.6 - 2.0 Ma B.P., the average value of pollen influx increased evidently compared with that of 3.0 - 2.6 Ma B.P. It shows that the sea level of SCS dropped dramatically around 2.6 Ma B.P., corresponding to the formation of the Northern Hemisphere ice-sheets and the enhancement of the East Asian Monsoon. The pollen influx variations reflect the glacial-interglacial cycles corresponding with the deep-sea oxygen isotope curve and indicate that the sea level of SCS rose and dropped many times after 2.6 Ma B.P. The spectrum analysis results of pollen influx show that there are cycles at 0.1Ma （eccentricity） and 46.9 ka （obliquity） during 3.0 - 2.0 Ma B.P.展开更多
Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic and paleoenvironmental evolution is recon- structed. The result of magnetic stratum ind...Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic and paleoenvironmental evolution is recon- structed. The result of magnetic stratum indicates that the lake basin was formed at about 2.8 MaBP, while the multi-proxy analyses of lithology, grain size, magnetic susceptibility and geo- chemical elements reveal that there have been three major environmental evolution stages and at least two intensive uplifts of the Tibetan Plateau in the lake basin area, i.e. during 2.8—2.5 MaBP, the lake basin came into being as a result of the disaggregation of the planation surface and rapid rising of the Tibetan Plateau. During 2.5—0.8 MaBP, with gradual uplift of the Tibetan Plateau, the environment of this area was more effectively controlled by the climatic cycle of the alternative glacial-interglacial stages. After 0.8 MaBP, the middle part of the Plateau accelerated its uplift and entered cryoshere.展开更多
文摘目的通过选择不同呼气末正压(PEEP)水平,观察对全麻术后患者氧合的影响。方法将全麻术后患者60例分为四组,给予不同水平PEEP,A组:PEEP 0 cm H2O、B组:PEEP 5 cmH2O、C组:PEEP 10 cm H2O,D组:PEEP 15 cm H2O,分别于呼吸机通气前、通气30 min、通气60 min时间点记录氧合指数、MABP值,比较患者氧合指数及MABP变化。结果与A组比较,B组、C组、D组在通气30 min、通气60 min氧合指数改善,有明显差异(P<0.05),B、C、D组间氧合指数比较无明显差异(P>0.05)。与A组比较,D组在通气30 min、通气60 min MABP下降,差异明显(P<0.05),B组、C组MABP无明显差异(P>0.05)。结论不同水平PEEP对全麻术后患者氧合指数均有明显改善,但PEEP 15 cm H2O时可造成MABP明显下降,对术后器官灌注有潜在危害。
基金the National Natural Science Foundation of China projects （40371116） the National Major Basic Research Program of China （G200078502）.
文摘In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 135 - 95 m （in composition depth） from ODP Site 1143 （9° 22＇ N, 113° 17＇ E） in the southern South China Sea. The results show that the pollen influx has a distinct change. During 2.6 - 2.0 Ma B.P., the average value of pollen influx increased evidently compared with that of 3.0 - 2.6 Ma B.P. It shows that the sea level of SCS dropped dramatically around 2.6 Ma B.P., corresponding to the formation of the Northern Hemisphere ice-sheets and the enhancement of the East Asian Monsoon. The pollen influx variations reflect the glacial-interglacial cycles corresponding with the deep-sea oxygen isotope curve and indicate that the sea level of SCS rose and dropped many times after 2.6 Ma B.P. The spectrum analysis results of pollen influx show that there are cycles at 0.1Ma （eccentricity） and 46.9 ka （obliquity） during 3.0 - 2.0 Ma B.P.
文摘Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic and paleoenvironmental evolution is recon- structed. The result of magnetic stratum indicates that the lake basin was formed at about 2.8 MaBP, while the multi-proxy analyses of lithology, grain size, magnetic susceptibility and geo- chemical elements reveal that there have been three major environmental evolution stages and at least two intensive uplifts of the Tibetan Plateau in the lake basin area, i.e. during 2.8—2.5 MaBP, the lake basin came into being as a result of the disaggregation of the planation surface and rapid rising of the Tibetan Plateau. During 2.5—0.8 MaBP, with gradual uplift of the Tibetan Plateau, the environment of this area was more effectively controlled by the climatic cycle of the alternative glacial-interglacial stages. After 0.8 MaBP, the middle part of the Plateau accelerated its uplift and entered cryoshere.
