ObjectiveTo establish a new biomechanical test for evaluating biomechanical properties of femoral metaphysis in ovariectomized rats.MethodsTwenty-five-month-old female Sprague-Dawley rats were randomly divided into ovariectomized (OVX) group and the sham-operated (Sham) group (n=10).Twelve weeks after operation,femur BMD and histomorphometry of distal femur were detected.Furthermore,femur biomechanical parameters were determined by diaphysis three-point bending test and a new designed metaphysis bending test.The relationships between the biomechanical parameters and BMD or bone histomorphometry were assessed with Pearson correlations.ResultsThe femur BMD,bone histomorphometrical indexes(％Th.Ar,Tb.N,Tb.Th),and biomechanical parameters(maximum load,yield load and stiffness) of OVX group significantly decreased compared with Sham group.In metaphysis bending test,the mean difference of the maximum load(Fmax),yield load(Fy) between group OVX and Sham were significant higher than that in diaphysis three-point bending test.Positive correlations between biomechanical parameters and femur BMD or bone histomorphometry indexes were observed in both the diaphysis bending and metaphysis bending test.The biomechanical parameters in the metaphysis bending test showed stronger correlations with BMD and bone.ConclusionFemur metaphysis bending test could be used to evaluate the biomechanical properties of osteoporosis.When compared with diaphysis bending test,femur metaphysis bending test is more sensitive in evaluating the change of biomechanical properties of femur in osteoporotic rats.

Objective To analyze and evaluate the effect of posterior circumferential fusion for treatment of the mechanical instability of lumbar spine, and discuss the relative merits,indications and contraindications in this procedure. Methods Two hundred and two patients with mechanical instability of lumbar spine treated by the posterior instrumented circumferential fusion technique from January 2001 to January 2007. One hundred and thirty-two patients were selected who were treated with only one segment fusion and followed up for at least 1 year, of them 97 patients suffered lumbar spondylolisthesis, 35 patients suffered degenerative lumbar instability. X-ray was used to evaluate the fusion condition of the bone graft, and VAS and ODI questionnaire were applied to assess the pain of back and leg,and the conventional function. Results All patients were followed up for 12-84 months, averaged (43±23) months,125 patients got bone fusion, accounted for 94.7%(125/132). The VAS of low back pain was (6.71 ± 1.31) points before operation, while (3.20 ± 1.14) points after operation (P < 0.05) ,and the VAS of leg pain was (8.33 ± 1.78) points before operation,while (4.31 ± 1.15) points after operation (P< 0.05). The ODI was (68.6 ± 14.7) % before operation, while (13.6 ± 1.5) % after operation (P < 0.05). Conclusions Posterior circumferential fusion is a positive and excellent treatment for the mechanical instability of lumbar spine. With its merits, the high fusion rate and good clinical results can be received.

Objective:To explore the distribution of airborne pollen in summer and autumn in Taiyuan, analyze the correlation between pollen characteristics, meteorological factors and allergic sensitization, and provide for the prevention and treatment of allergic diseases in this. Methods:The gravity sedimentation method was used to investigate the types, quantities and dispersion patterns of airborne pollen in Taiyuan City from July 21, 2022 to October 20, 2022. he meteorological and patient information was collected during the same period SPSS 26.0 software. Results:①A total of 17 118 pollen grains were collected, and identified as 14 families, 10 genera, and 4 species. The peak period for pollen dispersal in summer and autumn in Taiyuan City from late August to early September. airborne pollen Artemisia（66.62%）, Cannabis/Humulus（17.79%）, Sophora japonica（8.18%）, Chenopodiaceae/Amaranthaceae（2.83%）, Gramineae（2.11%）. ②The concentration of airborne pollen in Taiyuan City positively correlated with the average temperature（5-20℃） and maximum temperature（11-30℃） within a certain range（r=0.547, 0.315, P<0.05）. ③The content of airborne pollen in Taiyuan City positively correlated with the number of visits and allergen positive rate of patients with allergic rhinitis（AR） in our hospital（r=0.702, 0.747, P<0.05）. Conclusion:The peak period for airborne pollen dispersal during the summer and autumn seasons in Taiyuan City from late August to early September. The dominant pollen is Artemisia, Cannabis/Humulus, Sophora japonica, Chenopodiaceae/Amaranthaceae, Gramineae, and the absolute advantage pollen is Artemisia. Meteorological factors pollen content. Within a certain range, temperature the diffusion and transportation of pollen. The number of pollen grains the number of visits, which can serve as an environmental warning indicator for AR patients to take preventive, thereby reducing the risk of allergies.
Male ; Humans ; Seasons ; Pollen ; Rhinitis, Allergic ; Allergens ; Cities