It is reported in this article that the mandibular unilateral distal-extension remova-ble partial dentures with wrvught wtre retentive clasp arm,cast circumferential retentive arm andI-bar retentive arm were tested un...It is reported in this article that the mandibular unilateral distal-extension remova-ble partial dentures with wrvught wtre retentive clasp arm,cast circumferential retentive arm andI-bar retentive arm were tested under vertical loading,and the stresses around the root of thetooth adjacent to the extension base were ovserved by means of photoeiastic stress analysis.The results showed that the retentive clasp arm or reciprocal clasp arm in distal-extension remov-able partial denture does not affect the magnitude and direction of the abutment tooth force,that there is no obvious difference among the wrought wire clasp arm,cast circumferential clasparm and I-bar clasp on the abutment tooth force,and that the force created due to loading of re-movable partial denture is transmitted to the primary abutment tooth mainly through theocclusal rest.展开更多
Zebrafish are an effective vertebrate model to study the mechanisms underlying recovery after spinal cord injury.The subacute phase after spinal cord injury is critical to the recovery of neurological function,which i...Zebrafish are an effective vertebrate model to study the mechanisms underlying recovery after spinal cord injury.The subacute phase after spinal cord injury is critical to the recovery of neurological function,which involves tissue bridging and axon regeneration.In this study,we found that zebrafish spontaneously recovered 44%of their swimming ability within the subacute phase(2 weeks)after spinal cord injury.During this period,we identified 7762 differentially expressed genes in spinal cord tissue:2950 were up-regulated and 4812 were down-regulated.These differentially expressed genes were primarily concentrated in the biological processes of the respiratory chain,axon regeneration,and cell-component morphogenesis.The genes were also mostly involved in the regulation of metabolic pathways,the cell cycle,and gene-regulation pathways.We verified the gene expression of two differentially expressed genes,clasp2 up-regulation and h1m down-regulation,in zebrafish spinal cord tissue in vitro.Pathway enrichment analysis revealed that up-regulated clasp2 functions similarly to microtubule-associated protein,which is responsible for axon extension regulated by microtubules.Down-regulated h1m controls endogenous stem cell differentiation after spinal cord injury.This study provides new candidate genes,clasp2 and h1m,as potential therapeutic intervention targets for spinal cord injury repair by neuroregeneration.All experimental procedures and protocols were approved by the Animal Ethics Committee of Tianjin Institute of Medical&Pharmaceutical Sciences(approval No.IMPS-EAEP-Q-2019-02)on September 24,2019.展开更多
BACKGROUND：Similar to handedness, hand clasping and arm folding are also lateral preferences. Previous studies showed a variation frequency for hand clasping and arm folding among different populations. OBJECTIVE： T...BACKGROUND：Similar to handedness, hand clasping and arm folding are also lateral preferences. Previous studies showed a variation frequency for hand clasping and arm folding among different populations. OBJECTIVE： To investigate the relationship between patterns of lateral preferences （hand clasping or arm folding） and academic performance of middle school students. DESIGN, TIME AND SETTINGS： Cross-sectional investigation. The data were collected in the Beijing Zhongguancun High School in Beijing in May 2007. Data analysis was performed in the State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University during June to July 2007. PARTICIPANTS： A total of 102 senior-grade students from Beijing Zhongguancun High School, including 58 males and 44 females, were selected for this study. METHODS： Different forms of hand clasping and arm folding were recorded. More specifically, hand clasping was either right-thumb-top or left-thumb-top, and arm folding was either right-arm-top or left-arm-top. Students with congruent preference used right-thumb-top-right-arm-top or left-thumb-top-left-arm-top, and incongruent preference was displayed by right-thumb-top-left-arm-top or left-thumb-top-right-arm-top. Academic performances were collected from midterm exams in six subjects （Chinese, Mathematics, English, Physics, Chemistry, and Biology）, with a total points = 100 for each. A three-way （hand clasping, arm folding, and sex） ANOVA was performed to determine the effect on academic performances. MAIN OUTCOME MEASURES： The relationship between hand clasping, arm folding, sex, and academic performance of students. RESULTS： （1） There was no significant difference in distribution frequency between right-thumb-top and left-thumb-top （P 〉 0.05）, or between right-arm-top and left-arm-top （P 〉 0.05）. The distribution frequency difference between boys and girls was not significant for any subtype （P 〉 0.05）. （2） hand clasping had no significant main effect on any of the six subjects （P 〉 0.05）. The right-arm-top students received significantly higher points in Chinese, Physics, Chemistry, and Biology, compared with the left-arm-top students （P 〈 0.05）. A significant sexual difference was detected in academic performance in Chinese and English; girls had higher scores than the boys （P 〈 0.05）. The students with congruent preference scored higher in English, compared with those with incongruent preference （P 〈 0.05）. CONCLUSION： The arm folding form of lateral preference had a significant effect on academic performance of middle school students, implying that this human laterality index is of great functional importance.展开更多
文摘It is reported in this article that the mandibular unilateral distal-extension remova-ble partial dentures with wrvught wtre retentive clasp arm,cast circumferential retentive arm andI-bar retentive arm were tested under vertical loading,and the stresses around the root of thetooth adjacent to the extension base were ovserved by means of photoeiastic stress analysis.The results showed that the retentive clasp arm or reciprocal clasp arm in distal-extension remov-able partial denture does not affect the magnitude and direction of the abutment tooth force,that there is no obvious difference among the wrought wire clasp arm,cast circumferential clasparm and I-bar clasp on the abutment tooth force,and that the force created due to loading of re-movable partial denture is transmitted to the primary abutment tooth mainly through theocclusal rest.
基金the National Natural Science Foundation of China(No.81972074,to XY)the National Key R&D Project(No.2019YFA0112100,to SQF)+1 种基金Tianjin Key Research and Development Plan,Key Projects for Science and Technology Support(No.19YFZCSY00660,to SQF)Tianjin Medical University General Hospital Youth Incubation Fund(No.ZYYFY2018003,to WYS).
文摘Zebrafish are an effective vertebrate model to study the mechanisms underlying recovery after spinal cord injury.The subacute phase after spinal cord injury is critical to the recovery of neurological function,which involves tissue bridging and axon regeneration.In this study,we found that zebrafish spontaneously recovered 44%of their swimming ability within the subacute phase(2 weeks)after spinal cord injury.During this period,we identified 7762 differentially expressed genes in spinal cord tissue:2950 were up-regulated and 4812 were down-regulated.These differentially expressed genes were primarily concentrated in the biological processes of the respiratory chain,axon regeneration,and cell-component morphogenesis.The genes were also mostly involved in the regulation of metabolic pathways,the cell cycle,and gene-regulation pathways.We verified the gene expression of two differentially expressed genes,clasp2 up-regulation and h1m down-regulation,in zebrafish spinal cord tissue in vitro.Pathway enrichment analysis revealed that up-regulated clasp2 functions similarly to microtubule-associated protein,which is responsible for axon extension regulated by microtubules.Down-regulated h1m controls endogenous stem cell differentiation after spinal cord injury.This study provides new candidate genes,clasp2 and h1m,as potential therapeutic intervention targets for spinal cord injury repair by neuroregeneration.All experimental procedures and protocols were approved by the Animal Ethics Committee of Tianjin Institute of Medical&Pharmaceutical Sciences(approval No.IMPS-EAEP-Q-2019-02)on September 24,2019.
基金the National Natural Science of China, No. 30621130074
文摘BACKGROUND：Similar to handedness, hand clasping and arm folding are also lateral preferences. Previous studies showed a variation frequency for hand clasping and arm folding among different populations. OBJECTIVE： To investigate the relationship between patterns of lateral preferences （hand clasping or arm folding） and academic performance of middle school students. DESIGN, TIME AND SETTINGS： Cross-sectional investigation. The data were collected in the Beijing Zhongguancun High School in Beijing in May 2007. Data analysis was performed in the State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University during June to July 2007. PARTICIPANTS： A total of 102 senior-grade students from Beijing Zhongguancun High School, including 58 males and 44 females, were selected for this study. METHODS： Different forms of hand clasping and arm folding were recorded. More specifically, hand clasping was either right-thumb-top or left-thumb-top, and arm folding was either right-arm-top or left-arm-top. Students with congruent preference used right-thumb-top-right-arm-top or left-thumb-top-left-arm-top, and incongruent preference was displayed by right-thumb-top-left-arm-top or left-thumb-top-right-arm-top. Academic performances were collected from midterm exams in six subjects （Chinese, Mathematics, English, Physics, Chemistry, and Biology）, with a total points = 100 for each. A three-way （hand clasping, arm folding, and sex） ANOVA was performed to determine the effect on academic performances. MAIN OUTCOME MEASURES： The relationship between hand clasping, arm folding, sex, and academic performance of students. RESULTS： （1） There was no significant difference in distribution frequency between right-thumb-top and left-thumb-top （P 〉 0.05）, or between right-arm-top and left-arm-top （P 〉 0.05）. The distribution frequency difference between boys and girls was not significant for any subtype （P 〉 0.05）. （2） hand clasping had no significant main effect on any of the six subjects （P 〉 0.05）. The right-arm-top students received significantly higher points in Chinese, Physics, Chemistry, and Biology, compared with the left-arm-top students （P 〈 0.05）. A significant sexual difference was detected in academic performance in Chinese and English; girls had higher scores than the boys （P 〈 0.05）. The students with congruent preference scored higher in English, compared with those with incongruent preference （P 〈 0.05）. CONCLUSION： The arm folding form of lateral preference had a significant effect on academic performance of middle school students, implying that this human laterality index is of great functional importance.
