BACKGROUND:Porous structures based on triple periodic minimal surfaces are one of the most promising orthopedic biostructures,among which the Gyroid structure is characterized by high specific surface area,high permeability,and zero mean curvature.OBJECTIVE:To screen the wall thickness interval of TC4 bionic bone scaffolds with 4 mm single-cell Gyroid structure matching the elastic modulus range of cancellous bone of the mandible through finite element analysis combined with mechanical compression test testing.METHODS:The finite element model of the 4 mm single-cell Gyroid structure with different wall thickths(0.1,0.2,0.3,0.4,0.5,0.6,0.7,and 0.8 mm)was established.The equivalent elastic modulus of the Gyroid structure was analyzed,and the wall thickness interval of the Gyroid structure matching the elastic modulus range of the maxillary resinous bone was selected with different wall thicknesses of 0.2,0.3,0.4,0.5,0.6,and 0.7 mm,respectively.According to finite element analysis screening results,the material selected was Ti6Al4V.Selective laser melting was used to prepare 3D printed Gyroid structure specimens.The surface treatment was carried out by large-grained sand blasting and acid etching.The elastic modulus and compressive strength of the specimen were tested by mechanical compression experiment.RESULTS AND CONCLUSION:(1)The finite element analysis results showed that the equivalent elastic modulus of the Gyroid structure increased with the increase of wall thickness,and the equivalent elastic modulus of the Gyroid structure with wall thickness of 0.2-0.7 mm was within the range of the elastic modulus of the spongy bone of the mandible(1.5-4.0 GPa),which was used for 3D printing of the Gyroid structure specimen.(2)The mechanical compression test results showed that the elastic modulus and compressive strength of the Gyroid structural specimen increased with the increase of wall thickness,and the elastic modulus of the Gyroid structural specimen with wall thickness of 0.3-0.5 mm was within the range of the elastic modulus of the cancellous bone of the mandible.The compressive strength of the Gyroid specimen with 0.3-0.7 mm wall thickness was consistent with the mechanical properties of the mandible.(3)The results show that the Gyroid structure of 0.3-0.5 mm wall thickness is compatible with the range of elastic modulus of the mandible.

BACKGROUND:Porous structures based on triple periodic minimal surfaces are one of the most promising orthopedic biostructures,among which the Gyroid structure is characterized by high specific surface area,high permeability,and zero mean curvature.OBJECTIVE:To screen the wall thickness interval of TC4 bionic bone scaffolds with 4 mm single-cell Gyroid structure matching the elastic modulus range of cancellous bone of the mandible through finite element analysis combined with mechanical compression test testing.METHODS:The finite element model of the 4 mm single-cell Gyroid structure with different wall thickths(0.1,0.2,0.3,0.4,0.5,0.6,0.7,and 0.8 mm)was established.The equivalent elastic modulus of the Gyroid structure was analyzed,and the wall thickness interval of the Gyroid structure matching the elastic modulus range of the maxillary resinous bone was selected with different wall thicknesses of 0.2,0.3,0.4,0.5,0.6,and 0.7 mm,respectively.According to finite element analysis screening results,the material selected was Ti6Al4V.Selective laser melting was used to prepare 3D printed Gyroid structure specimens.The surface treatment was carried out by large-grained sand blasting and acid etching.The elastic modulus and compressive strength of the specimen were tested by mechanical compression experiment.RESULTS AND CONCLUSION:(1)The finite element analysis results showed that the equivalent elastic modulus of the Gyroid structure increased with the increase of wall thickness,and the equivalent elastic modulus of the Gyroid structure with wall thickness of 0.2-0.7 mm was within the range of the elastic modulus of the spongy bone of the mandible(1.5-4.0 GPa),which was used for 3D printing of the Gyroid structure specimen.(2)The mechanical compression test results showed that the elastic modulus and compressive strength of the Gyroid structural specimen increased with the increase of wall thickness,and the elastic modulus of the Gyroid structural specimen with wall thickness of 0.3-0.5 mm was within the range of the elastic modulus of the cancellous bone of the mandible.The compressive strength of the Gyroid specimen with 0.3-0.7 mm wall thickness was consistent with the mechanical properties of the mandible.(3)The results show that the Gyroid structure of 0.3-0.5 mm wall thickness is compatible with the range of elastic modulus of the mandible.

Surgical nutrition therapy is a novel course for undergraduates who are major in food hygiene and nutrition.In this study,the purpose,content,model and specific teaching approaches of the course were discussed,and the essentials of clinical practice for surgical nutrition therapy were pointed out.We hope that our experience would be helpful for the development of the course.

Teaching purpose, teaching content, experiment and examination forms etc. were discussed, and how to practice the teaching of the public selective course Nutriology of Traditional Chinese Medicine was pointed out. All these are invaluable experience for the development and progress of this course.

Objective To study the plasma TNF-α and endothelin (ET) levels in patient with subarach-noid hemorrhage(SAH). Methods The plasma TNF-α and ET levels were measured by ELISA and radioimmunity at 1,3,7,14 and 21 d after onset of SAH in 45 patients. Results The plasma TNF-α and ET levels in patients with SAH were higher than the normal controls(P<0.01),among which the highest levels appeared at 3 d and 7 d,and the levels of plasma TNF-α and ET in patients with SAH were decreased at 14 d. Those of high Hunt-Hess grade～groups was higher than those of lower grade～groups(P<0.01). Conclusion The plasma TNF-α and ET levels are significantly elevated in the patients with SAH,which suggests that TNF-α and ET may play an important role in the pathogenesis of SAH,and which suggests that is one of the possible ways to prevent and treat cardiovascular spasm (CVS) after SAH by inhibiting TNF-α and ET.

OBJECTIVEThe purpose of this study was to investigate the relationship between the results of flowcytometry analyses of different clinical stage, location, pathologic grade and cell origin of oral and maxillofacial non-Hodgkin's lymphoma (NHL), and the diagnostic value of flowcytometry analysis in lymphoma.

METHODThis study analyzed 50 oral and maxillofacial NHL cases and 10 reactive lymph nodes (formalin fixed and paraffin embedded) by flowcytometry (FCM).

RESULTSReactive lymph nodes were all diploid. The diploid rate of NHL was 54%, and aneuploidy rate was 46%. There was statistically significant difference between reactive lymph nodes and NHL in the DNA ploidy status and cell cycle data (SPF, CV, S + G2/M, DI). The S phase fraction (SPF) and S + G2/M had close relationship with the grade of NHL. SPF value and DNA ploidy status had no obvious relationship with the prognosis.

CONCLUSIONThe results suggested that the FCM had diagnostic value in NHL, especially when the morphological diagnosis was difficult. Although the cell cycle data had no prognostic value, SPF and SPF + G2/M can show the proliferative status of NHL, which can help clinical doctor select therapeutic method.

Cell Cycle ; DNA, Neoplasm ; analysis ; Facial Neoplasms ; diagnosis ; genetics ; pathology ; Flow Cytometry ; Humans ; Lymphoma, Non-Hodgkin ; diagnosis ; genetics ; pathology ; Maxillary Neoplasms ; diagnosis ; genetics ; pathology ; Mouth Neoplasms ; diagnosis ; genetics ; pathology ; Ploidies ; Prognosis