Reeds are widely distributed in drought and high salt conditions of northwestern China. Leaf epidermal micromorphology, anatomy, chloroplast ultrastructure and physio-chemical characteristics due to long-term adaptati...Reeds are widely distributed in drought and high salt conditions of northwestern China. Leaf epidermal micromorphology, anatomy, chloroplast ultrastructure and physio-chemical characteristics due to long-term adaptation in the natural habitats of common reed （Phragmites communis Trin.） contrasted considerably among three different ecotypes： dune reed （DR）, Gobi salt reed （GSR） and swamp reed （SR）. The main objective of the present study is to determine the adapting characteristics of morphology, anatomy and physiological responses of thin roots in DR, GSR and SR. The results show that root length density was higher in SR and few root hairs were observed in DR. Cross-section anatomical features show that each ecotype has an endodermis and exodermis, while cortex thickness and proportion of root cortical aerenchyma and stele in root structure varied among the three ecotypes. The stele and xylem share a larger area in DR compared to GSR and SR. GSR has a large proportion of the cortex with radialized distribution of aerenchyma cells spacing, and the cortex has a peripheral, mechanically stiff ring in the exodermis. SEM and TEM microscope images show that GSR has a scle- renchyma ring with high lignification in the exodermis. The physio-chemical parameters show that GSR had a higher level of stress tolerance than DR. These findings indicate that developed water-absorbing tissues were largely distributed in the root structure of DR, and a main framework with supporting function spacing with aerenchyma was dominant in GSR in the long term adaptation to their natural habitats, respectively.展开更多
目的寻求建立颈丛及周围结构数字模型及三维可视化的方法。方法取健康志愿者头顶至第3胸椎下缘连续CT血管成像(CTA)动脉造影及MR脊髓造影(MRM)断面图像,经内插值处理达到亚体素精度,调整窗位、窗宽及对比度使其达到最佳视度。在CTA血管...目的寻求建立颈丛及周围结构数字模型及三维可视化的方法。方法取健康志愿者头顶至第3胸椎下缘连续CT血管成像(CTA)动脉造影及MR脊髓造影(MRM)断面图像,经内插值处理达到亚体素精度,调整窗位、窗宽及对比度使其达到最佳视度。在CTA血管造影断层数据集中,基于骨骼CT阈值,采用Mimics软件,以Thresholding和Region Growing工具进行半自动分割,重建骨骼结构的三维数字模型,基于动脉、静脉、甲状腺、喉软骨在血管造影不同时期CT阈值的差异,以Thresholding和Dynamic Region Growing工具进行分割,重建升主动脉、主动脉弓、锁骨下动脉、颈总动脉、椎动脉、颈外静脉、颈内静脉、锁骨下静脉、胸锁乳突肌、甲状腺、舌骨和喉软骨(甲状软骨)的三维数字模型。以医学计算机辅助设计(MedCAD)模块对肌肉、颈丛等细小解剖结构重建,三维化显示颈丛及周围相关解剖结构。结果建立了颈丛及周围结构的三维可视化模型,可清晰显示骨性结构、主动脉、上腔静脉、胸锁乳突肌、中斜角肌、肩胛提肌、脊髓、颈丛皮支(枕小神经、耳大神经、颈横神经、锁骨上神经)和膈神经等解剖结构的位置关系。结论颈丛及周围结构三维可视化模型可以为骨科和颈丛麻醉提供解剖形态学参考。展开更多
基金financially supported by the State Key Development Program for Basic Research of China(973 Program,Grant No.2013CB429904)the National Natural Science Foundation of China(Grant No.91125029)
文摘Reeds are widely distributed in drought and high salt conditions of northwestern China. Leaf epidermal micromorphology, anatomy, chloroplast ultrastructure and physio-chemical characteristics due to long-term adaptation in the natural habitats of common reed （Phragmites communis Trin.） contrasted considerably among three different ecotypes： dune reed （DR）, Gobi salt reed （GSR） and swamp reed （SR）. The main objective of the present study is to determine the adapting characteristics of morphology, anatomy and physiological responses of thin roots in DR, GSR and SR. The results show that root length density was higher in SR and few root hairs were observed in DR. Cross-section anatomical features show that each ecotype has an endodermis and exodermis, while cortex thickness and proportion of root cortical aerenchyma and stele in root structure varied among the three ecotypes. The stele and xylem share a larger area in DR compared to GSR and SR. GSR has a large proportion of the cortex with radialized distribution of aerenchyma cells spacing, and the cortex has a peripheral, mechanically stiff ring in the exodermis. SEM and TEM microscope images show that GSR has a scle- renchyma ring with high lignification in the exodermis. The physio-chemical parameters show that GSR had a higher level of stress tolerance than DR. These findings indicate that developed water-absorbing tissues were largely distributed in the root structure of DR, and a main framework with supporting function spacing with aerenchyma was dominant in GSR in the long term adaptation to their natural habitats, respectively.
文摘目的寻求建立颈丛及周围结构数字模型及三维可视化的方法。方法取健康志愿者头顶至第3胸椎下缘连续CT血管成像(CTA)动脉造影及MR脊髓造影(MRM)断面图像,经内插值处理达到亚体素精度,调整窗位、窗宽及对比度使其达到最佳视度。在CTA血管造影断层数据集中,基于骨骼CT阈值,采用Mimics软件,以Thresholding和Region Growing工具进行半自动分割,重建骨骼结构的三维数字模型,基于动脉、静脉、甲状腺、喉软骨在血管造影不同时期CT阈值的差异,以Thresholding和Dynamic Region Growing工具进行分割,重建升主动脉、主动脉弓、锁骨下动脉、颈总动脉、椎动脉、颈外静脉、颈内静脉、锁骨下静脉、胸锁乳突肌、甲状腺、舌骨和喉软骨(甲状软骨)的三维数字模型。以医学计算机辅助设计(MedCAD)模块对肌肉、颈丛等细小解剖结构重建,三维化显示颈丛及周围相关解剖结构。结果建立了颈丛及周围结构的三维可视化模型,可清晰显示骨性结构、主动脉、上腔静脉、胸锁乳突肌、中斜角肌、肩胛提肌、脊髓、颈丛皮支(枕小神经、耳大神经、颈横神经、锁骨上神经)和膈神经等解剖结构的位置关系。结论颈丛及周围结构三维可视化模型可以为骨科和颈丛麻醉提供解剖形态学参考。
