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91.
目的:通过测试颈椎标本在静止中立位及模拟头部重量后的髓核内压力,从而探讨颈椎髓核内压力的变化规律。方法:利用生物力学材料实验机及微型压力传感器测试新鲜人体颈椎标本在静止中立位及加载100N压力时的髓核内压力。结果:静止中立位及加载100N压力时,C3~4和C4~5节段髓核内压力比较无显著性差异(P0.05),C5~6和C6~7节段髓核内压力比较无显著性差异(P0.05);C5~6,C6~7高于C3~4,C4~5髓核内压力(P0.05);加载100N后所有节段髓核内压力均升高具有显著性差异(P0.05)。结论:正常人体下颈段髓核内压力高于上颈段髓核内压力,并且随外在负荷的增加而压力增加。 相似文献
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光学相干层析技术是一种高分辨率成像方法。它是一种无损伤、非介入、非离子辐射的探测技术,具有较高的空间分辨率。有限元分析(FEA)是用于工程科学的重要工具,FEMLAB(Finite Element Modeling Laboratory)是基于偏微分方程的对科学和工程问题进行建模和仿真计算的交互式系统。本文简要介绍了OCT成像技术的原理及FEMLAB的应用步骤,重点用FEMLAB软件对脑组织内光场的分布情况进行分析,从而利用分析结果论证OCT成像在脑外科手术中应用的可行性。 相似文献
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Zhen Wang Yan-Qun Liu Yu-Hang Zhao Qing-Pu Zhang Yu-Ling Sun Bin-Bin Yang Jian-Hua Bu Chun Zhang 《RSC advances》2022,12(26):16486
It remains a great challenge to effectively control the pore size in porous organic polymers (POPs) because of the disordered linking modes. Herein, we used organic molecular cages (OMCs), possessing the properties of fixed intrinsic cavities, high numbers of reactive sites and dissolvable processability, as building blocks to construct a molecular cage-based POP (TPP-pOMC) with high valency through covalent cross coupling reaction. In the formed TPP-pOMC, the originating blocking pore channels of TPP-OMC were “turned on” and formed fixed pore channels (5.3 Å) corresponding to the connective intrinsic cavities of cages, and intermolecular pore channels (1.34 and 2.72 nm) between cages. Therefore, TPP-pOMC showed significant enhancement in Brunauer–Emmett–Teller (BET) surface area and CO2 adsorption capacity.By utilizing the cage to framework strategy, the blocking pores of the cage itself were “turned on” to construct a highly covalent molecular cage based porous organic polymer. 相似文献
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Tongtong Shen Qijun Shan Biao Yuan Bing Yang Chun Chen Dongjie Xu Minglong Chen Jiangang Zou Kejiang Cao 《生物医学研究杂志》2007,21(3):139-142
Objective: To investigate the incidence and relative risk factors of post coronary artery bypass grafting(post-CABG) atrial fibrillation (AF). Methods: 312 patients with CABG were reviewed and divided into an AF group and a non-AF group. Statistical analysis was used to compare the data between the two groups and screen for risk factors of post-CABG AF. Results: 103/312(33.01%) patients developed post-CABG AF. Univariate analysis showed that patients in AF group compared with those in non-AF group were more likely to have advanced age (≥ 70 years), early postoperative withdrawal of β-blockers, hypertension, left atrial enlargement ( ≥40 mm), a history of AF, prolonged p-wave duration ( ≥ 120 ms) and increased number of grafts (≥3). Multivariate logistic regression analysis showed that advanced age (≥70 years), early postoperative withdrawal of β-blockers, hypertension, left atrial enlargement (≥40 mm) and a history of AF were highly related to post-CABG AF. Conclusion: The incidence of AF in patients following CABG was 33.01% in this study. Advanced age, early postoperative withdrawal of β-blockers,hypertension, left atrial enlargement and a history of AF were independent risk factors of post-CABG AF. 相似文献
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Minji Kang Ryeon Heo Seojin Park Seo-Yeong Mun Minju Park Eun-Taek Han Jin-Hee Han Wanjoo Chun Kwon-Soo Ha Hongzoo Park Won-Kyo Jung Il-Whan Choi Won Sun Park 《The Korean journal of physiology & pharmacology》2022,26(4):277
To investigate the adverse effects of clozapine on cardiovascular ion channels, we examined the inhibitory effect of clozapine on voltage-dependent K+ (Kv) channels in rabbit coronary arterial smooth muscle cells. Clozapine-induced inhibition of Kv channels occurred in a concentration-dependent manner with an half-inhibitory concentration value of 7.84 ± 4.86 µM and a Hill coefficient of 0.47 ± 0.06. Clozapine did not shift the steady-state activation or inactivation curves, suggesting that it inhibited Kv channels regardless of gating properties. Application of train pulses (1 and 2 Hz) progressively augmented the clozapine-induced inhibition of Kv channels in the presence of the drug. Furthermore, the recovery time constant from inactivation was increased in the presence of clozapine, suggesting that clozapine-induced inhibition of Kv channels is use (state)-dependent. Pretreatment of a Kv1.5 subtype inhibitor decreased the Kv current amplitudes, but additional application of clozapine did not further inhibit the Kv current. Pretreatment with Kv2.1 or Kv7 subtype inhibitors partially blocked the inhibitory effect of clozapine. Based on these results, we conclude that clozapine inhibits arterial Kv channels in a concentration- and use (state)-dependent manner. Kv1.5 is the major subtype involved in clozapine-induced inhibition of Kv channels, and Kv2.1 and Kv7 subtypes are partially involved. 相似文献
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Edimansyah Abdin Siow Ann Chong Janhavi Ajit Vaingankar Saleha Shafie Darren Seah Chun Ting Chan Stefan Ma Lyn James Derrick Heng Mythily Subramaniam 《Singapore medical journal》2022,63(4):196
INTRODUCTIONFew studies have examined the changes in the prevalence of comorbidity of mental and physical disorders in recent years. The present study sought to examine whether the prevalence of comorbidity of mental and physical disorders in Singapore showed any changes between 2010 and 2016.METHODSWe extracted data from two repeated nationally representative cross-sectional surveys conducted among resident adults aged ≥ 18 years in Singapore. Significant changes were tested using pooled multinomial logistic regression analyses.RESULTSThe prevalence of comorbid mental and physical disorders increased significantly from 5.8% in 2010 to 6.7% in 2016. Among those with physical disorders, there were significant increases over time in the prevalence of comorbid generalised anxiety disorder (GAD) (0.1% vs. 0.4%) and obsessive-compulsive disorder (OCD) (1.4% vs. 3.9%) in diabetes mellitus, and alcohol dependence in cardiovascular disorders (0.1% vs. 1.3%). Among those with mental disorders, there were significant increases over time in the prevalence of comorbid diabetes mellitus in OCD (4.1% vs. 10.9%), cancer in major depressive disorder (0.4% vs. 2.4%), and cardiovascular disorders in GAD (0.4% vs. 6.7%) and alcohol dependence (0.9% vs. 11.8%). Significant changes in the overall prevalence of comorbid mental and physical disorders were also observed across age group, education and employment status.CONCLUSIONThe prevalence of comorbid mental and physical disorders increased significantly over time. This finding supports the need for more appropriate clinical management with better integration between mental health and general medical care professionals across all aspects of the healthcare system to treat this comorbidity in Singapore. 相似文献