Biomechanical study on the treatment of intertrochanteric fracture of A3.3 type with medial sustainable nail and proximal femoral anti-rotation nail / 中国骨伤

OBJECTIVE@#A3 intertrochanteric fracture is an extremely unstable fracture, which is often treated with intramedullary nail, but the implant failure is common due to the posterior medial fragment cannot be reconstructed. A new medial sustainable nail (MSN-Ⅱ) which can reconstruct the femoral medial support by sustainable screw was introduced in this study. The mechanical effect was verified by biomechanical experiment.@*METHODS@#The loss medial support model of intertrochanteric fracture (A3) was made by artificial Sawbones model, fixed with MSN-Ⅱ and PFNA-Ⅱ, underwent axial loading and axial failure tests. The axial stiffness, yield load, displacement of head-neck fragment and torsional angle of fracture site of these nails were recorded and compared for biomechanical differences. The effect of early reconstruction of medial support with MSN-Ⅱ was determined.@*RESULTS@#The axial stiffness, yield load, the displacement of head and neck fragment when the axial load was 1 800 N and torsional angle of the fracture site after the axial failure test of MSN-Ⅱ were (222.76 ±62.46) N /mm, (4 241.71 ±847.42) N, (11.51 ±0.62) mm, (1.71 ±0.10)° respectively, while the PFNA -Ⅱ was (184.58±40.59) N /mm, (3 058.76±379.63) N, (16.15±1.36) mm, (2.52±0.26)°respectively. The difference between the two groups was statistically significant.@*CONCLUSION@#The axial stiffness of MSN-Ⅱ is better than that of PFNA-Ⅱ. The MSN-Ⅱ can bear more loads when fixed A3.3 intertrochanteric fracture and has greater axial and rotational stability. It is an effective means to reconstruct the medial support of A3 intertrochanteric fracture.

Study on purification technology of patchouly oil with molecular distillation / 中国中药杂志

<p><b>OBJECTIVE</b>To establish an advanced purification techniques of the essential oils obtained from Pogostemon cablin.</p><p><b>METHOD</b>Molecular distillation (MD) was applied.</p><p><b>RESULT</b>Four distillates were obtained, chemical constituents of which were analyzed with GC-MS. Compared with those in original oils, the contents of active compounds (patchouli alcohol and pogostone) rose by 27%-47% in the distillates II and III.</p><p><b>CONCLUSION</b>Molecular distillation (MD) effectively raises the contents of patchouli alcohol and pogostone. The work is of great economic and scientific significance for the industrialization of P. cablin and the discovery of new drugs.</p>