目的利用Orbscan-Ⅱ测量准分子激光原位角膜磨镶术(laser in situ reratomileusis,LASIK)术前术后眼前节参数的改变,探讨Orbscan-Ⅱ在LASIK术后测量不同屈光度近视的眼前节参数中可能存在的误差。方法应用Orb-scan-Ⅱ角膜地形图系统对进...目的利用Orbscan-Ⅱ测量准分子激光原位角膜磨镶术(laser in situ reratomileusis,LASIK)术前术后眼前节参数的改变,探讨Orbscan-Ⅱ在LASIK术后测量不同屈光度近视的眼前节参数中可能存在的误差。方法应用Orb-scan-Ⅱ角膜地形图系统对进行LASIK术的48例88眼于术前、术后第1个月测量角膜厚度和前房深度,术前根据屈光度分组:Ⅰ组-2.00～-6.00D,Ⅱ组-6.25～-12.50D。分别比较各组术前理论预测术后角膜最薄点厚度值和术后实际测量值、术前术后中央前房深度测量值之间的差异。结果Ⅰ组术前理论预测术后角膜最薄点厚度与术后实际测量角膜最薄点厚度比较,差异无统计学意义(P>0.05)。Ⅱ组术前理论预测术后角膜最薄点厚度与术后实际测量角膜最薄点厚度比较,差异有统计学意义(P<0.05),术后实际测量值小于术前理论预测值。两组术前术后测量中央前房深度值比较,差异有统计学意义(P<0.05),术后测量值小于术前测量值。结论Orbscan-Ⅱ对术后角膜厚度及前房深度的测量存在误差,术后角膜后表面前凸、角膜水肿混浊、调节的增加等是影响其准确性的可能因素。展开更多
Scanning tunneling microscopy （STM） and scanning tunneling spectroscopy （STS） were performed on monolayer film of NiTPP supported on Au（111） under ultrahigh vacuum （UHV） conditions. The constant current STM im...Scanning tunneling microscopy （STM） and scanning tunneling spectroscopy （STS） were performed on monolayer film of NiTPP supported on Au（111） under ultrahigh vacuum （UHV） conditions. The constant current STM images show remarkable bias dependence. High resolution STM data clearly show the individual NiTPP molecules and allow easy differentiation between NiTPP and CoTPP reported before. Scanning tunneling spectra, as a function of molecule-tip separation, were acquired over a range of tip motion of 0.42 nm. Spectra do not show the variation in band splitting with tip distance. It appears for molecules such as NiTPP that the average potential at the molecule is essentially the same at the same metal substrate. For molecules of the height of NiTPP, the scanning tunneling spectra should give reliable occupied and unoccupied orbital energies over a wide range of tip-molecule distances.展开更多
准分子激光原位角膜磨镶术（laser in situ keratomileusis,LASIK）是目前应用最广泛的角膜屈光手术,而精确的角膜厚度测量是手术能否成功的一项重要参数,它对患者的选择、手术设计、切削深度的判断有着指导作用。目前0rbscan-Ⅱ眼前节...准分子激光原位角膜磨镶术（laser in situ keratomileusis,LASIK）是目前应用最广泛的角膜屈光手术,而精确的角膜厚度测量是手术能否成功的一项重要参数,它对患者的选择、手术设计、切削深度的判断有着指导作用。目前0rbscan-Ⅱ眼前节分析系统和超声角膜测厚仪是最常用的测厚方法。展开更多
文摘目的利用Orbscan-Ⅱ测量准分子激光原位角膜磨镶术(laser in situ reratomileusis,LASIK)术前术后眼前节参数的改变,探讨Orbscan-Ⅱ在LASIK术后测量不同屈光度近视的眼前节参数中可能存在的误差。方法应用Orb-scan-Ⅱ角膜地形图系统对进行LASIK术的48例88眼于术前、术后第1个月测量角膜厚度和前房深度,术前根据屈光度分组:Ⅰ组-2.00～-6.00D,Ⅱ组-6.25～-12.50D。分别比较各组术前理论预测术后角膜最薄点厚度值和术后实际测量值、术前术后中央前房深度测量值之间的差异。结果Ⅰ组术前理论预测术后角膜最薄点厚度与术后实际测量角膜最薄点厚度比较,差异无统计学意义(P>0.05)。Ⅱ组术前理论预测术后角膜最薄点厚度与术后实际测量角膜最薄点厚度比较,差异有统计学意义(P<0.05),术后实际测量值小于术前理论预测值。两组术前术后测量中央前房深度值比较,差异有统计学意义(P<0.05),术后测量值小于术前测量值。结论Orbscan-Ⅱ对术后角膜厚度及前房深度的测量存在误差,术后角膜后表面前凸、角膜水肿混浊、调节的增加等是影响其准确性的可能因素。
基金This work was supported by the Excellent Scientist Program of South China University of Technology (324-D60090), the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry and the National Natural Science Foundation of China (20643001).
文摘Scanning tunneling microscopy （STM） and scanning tunneling spectroscopy （STS） were performed on monolayer film of NiTPP supported on Au（111） under ultrahigh vacuum （UHV） conditions. The constant current STM images show remarkable bias dependence. High resolution STM data clearly show the individual NiTPP molecules and allow easy differentiation between NiTPP and CoTPP reported before. Scanning tunneling spectra, as a function of molecule-tip separation, were acquired over a range of tip motion of 0.42 nm. Spectra do not show the variation in band splitting with tip distance. It appears for molecules such as NiTPP that the average potential at the molecule is essentially the same at the same metal substrate. For molecules of the height of NiTPP, the scanning tunneling spectra should give reliable occupied and unoccupied orbital energies over a wide range of tip-molecule distances.
文摘准分子激光原位角膜磨镶术（laser in situ keratomileusis,LASIK）是目前应用最广泛的角膜屈光手术,而精确的角膜厚度测量是手术能否成功的一项重要参数,它对患者的选择、手术设计、切削深度的判断有着指导作用。目前0rbscan-Ⅱ眼前节分析系统和超声角膜测厚仪是最常用的测厚方法。
