RESUMO Introdução As características peculiares da patinação de velocidade em pista curta devem ser integradas na psicologia das competições; considera-se que os atletas de elite engajados nesta modalidade especial devem ter boa condição psíquica. Objetivo Investigar o poder explosivo das patinadoras de patinação de velocidade em pista curta. Métodos 10 atletas-chave da equipe nacional de patinação de velocidade em pista curta foram selecionadas, o poder explosivo foi testado por teste T, teste hexagonal e teste de sensibilidade pro. A análise dos dados foi realizada utilizando um teste t de amostra independente, as diferenças nos resultados dos indicadores de teste relacionados entre os grupos foram analisadas, e foi utilizada a análise de medidas repetidas de variação. Resultados Durante a fase de pontapé explosivo, a velocidade da extensão do joelho aumentou linearmente de 210°/S para 600°/S, e a velocidade da extensão do quadril aumentou linearmente de 200°/S para 400°/S. Conclusão O desenvolvimento da força do grupo muscular e do poder explosivo durante o treinamento muitas vezes apresenta diferenças no grau de contração, o que está relacionado com a disposição dos métodos de treinamento. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

ABSTRACT Introduction The peculiar characteristics of short track speed skating should be integrated into the psychology of competitions; it is considered that elite athletes engaged in this particular sport should have a healthy psychic condition. Objective Investigate the explosive power of female speed skaters in short track speed skating. Methods 10 key athletes from the national short track speed skating team were selected, and explosive power was tested by T-test, hexagonal test, and pro sensitivity test. Data analysis was performed using an independent sample t-test, differences in the results of related test indicators between groups were analyzed, and repeated measures analysis of variance was used. Results During the explosive kick phase, knee extension speed increased linearly from 210°/S to 600°/S, and hip extension speed increased linearly from 200°/S to 400°/S. Conclusion The development of muscle group strength and explosive power during training often shows differences in the degree of contraction, which is related to the arrangement of training methods. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMEN Introducción Las características peculiares del patinaje de velocidad en pista corta deben integrarse en la psicología de las competiciones; se considera que los atletas de élite que se dedican a esta modalidad especial deben tener una buena condición psíquica. Objetivo Investigar la potencia explosiva de las patinadoras de velocidad en pista corta. Métodos Se seleccionaron 10 atletas clave del equipo nacional de patinaje de velocidad en pista corta, se probó la potencia explosiva mediante la prueba T, la prueba hexagonal y la prueba de sensibilidad pro. El análisis de los datos se realizó mediante una prueba t de muestras independientes, se analizaron las diferencias en los resultados de los indicadores de las pruebas relacionadas entre los grupos y se utilizó el análisis de varianza de medidas repetidas. Resultados Durante la fase de patada explosiva, la velocidad de extensión de la rodilla aumentó linealmente de 210°/S a 600°/S, y la velocidad de extensión de la cadera aumentó linealmente de 200°/S a 400°/S. Conclusión El desarrollo de la fuerza y la potencia explosiva de los grupos musculares durante el entrenamiento suele mostrar diferencias en el grado de contracción, lo que está relacionado con la disposición de los métodos de entrenamiento. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

RESUMO Introdução Embora o tempo de desenvolvimento da patinação em pista curta na China seja relativamente curto, com os esforços conjuntos de muitos atletas e treinadores, o nível técnico especial pode ser comparável com o dos países europeus e americanos. Objetivo Verificar os impactos do treinamento de coordenação física sobre a velocidade na patinação de velocidade em pista curta. Métodos Atletas da equipe de patinação provincial foram aleatoriamente selecionados e distribuídos em grupos controle e experimental para aplicar o método de treinamento na coordenação física de patinação de velocidade em pista curta. Resultados A taxa média de gordura corporal dos patinadores no grupo controle foi 15,24%, a taxa média de gordura corporal no grupo de controle foi 15,20%, e o valor de T do grupo experimental e do grupo de controle foi 1,00, P = 0,374 < 0,05. Conclusão Por serem equipamentos especiais, o dispositivo de treinamento de resistência à curva e o paraquedas de resistência ao ar desempenharam um papel importante na melhoria da aptidão física especial dos patinadores chineses de velocidade em pista curta. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

ABSTRACT Introduction Although the development time of short-track speed skating in China is relatively short, with the joint efforts of many athletes and coaches, the special technical level can be comparable with that of European and American countries. Objective Verify the impacts of physical coordination training on speed in short track speed skating. Methods Athletes from the provincial skating team were randomly selected and distributed into control and experimental groups to apply the training method on physical coordination in short track speed skating. Results The average body fat rate of the skaters in the control group was 15.24%, the average body fat rate in the control group was 15.20%, and the T value of the experimental group and control group was 1.00, P = 0.374 < 0.05. Conclusion Because they are special equipment, the turn resistance training device and the air resistance parachute played an important role in improving the special fitness of Chinese short track speed skaters. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMEN Introducción Aunque el tiempo de desarrollo del patinaje de velocidad en pista corta en China es relativamente corto, con el esfuerzo conjunto de muchos atletas y entrenadores, el nivel técnico especial puede ser comparable al de los países europeos y americanos. Objetivo Verificar los impactos del entrenamiento de la coordinación física sobre la velocidad en el patinaje de velocidad en pista corta. Métodos Se seleccionaron aleatoriamente atletas del equipo provincial de patinaje y se distribuyeron en grupos de control y experimentales para aplicar el método de entrenamiento de la coordinación física en el patinaje de velocidad en pista corta. Resultados El índice medio de grasa corporal de los patinadores del grupo de control fue del 15,24%, el índice medio de grasa corporal del grupo de control fue del 15,20%, y el valor T del grupo experimental y del grupo de control fue de 1,00, P = 0,374 < 0,05. Conclusión Debido a que son equipos especiales, el dispositivo de entrenamiento de resistencia en curva y el paracaídas de resistencia al aire desempeñaron un papel importante en la mejora de la aptitud física especial de los patinadores de velocidad de pista corta chinos. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

OBJECTIVES: Osteoporotic vertebral compression fractures (OVCFs) affect the elderly population, especially postmenopausal women. Percutaneous kyphoplasty is designed to treat painful vertebral compression fractures for which conservative therapy has been unsuccessful. High-viscosity cement can be injected by either a hydraulic pressure delivery system (HPDS) or a balloon tamp system (BTS). Therefore, the purpose of this study was to compare the safety and clinical outcomes of these two systems. METHODS: A random, multicenter, prospective study was performed. Clinical and radiological assessments were carried out, including assessments of general surgery information, visual analog scale, quality of life, cement leakage, and height and angle restoration. RESULTS: Using either the HPDS or BTS to inject high-viscosity cement effectively relieved pain and improved the patients’ quality of life immediately, and these effects lasted at least two years. The HPDS using high-viscosity cement reduced cost, surgery time, and radiation exposure and showed similar clinical results to those of the BTS. In addition, the leakage rate and the incidence of adjacent vertebral fractures after the HPDS treatment were reduced compared with those after treatment using the classic vertebroplasty devices. However, the BTS had better height and angle restoration abilities. CONCLUSIONS: The percutaneous HPDS with high-viscosity cement has similar clinical outcomes to those of traditional procedures in the treatment of vertebral fractures in the elderly. The HPDS with high-viscosity cement is better than the BTS in the treatment of mild and moderate OVCFs and could be an alternative method for the treatment of severe OVCFs.

BACKGROUND: Black widow spider (L. tredecimguttatus) has toxic components not only in the venomous glands, but also in other parts of the body and its eggs. It is biologically important to investigate the molecular basis of the egg toxicity. RESULTS: In the present work, an aqueous extract was prepared from the eggs of the spider and characterized using multiple physiological and biochemical strategies. Gel electrophoresis and mass spectrometry demonstrated that the eggs are rich in high-molecular-mass proteins and the peptides below 5 kDa. The lyophilized extract of the eggs had a protein content of 34.22% and was shown to have a strong toxicity towards mammals and insects. When applied at a concentration of 0.25 mg/mL, the extract could completely block the neuromuscular transmission in mouse isolated phrenic nerve-hemidiaphragm preparations within 12.0 ± 1.5 min. Using whole-cell patch-clamp technique, the egg extract was demonstrated to be able to inhibit the voltage-activated Na+, K+and Ca2+ currents in rat DRG neurons. In addition, the extract displayed activities of multiple hydrolases. Finally, the molecular basis of the egg toxicity was discussed. CONCLUSIONS: The eggs of black widow spiders are rich in proteinous compounds particularly the high-molecular-mass proteins with different types of biological activity The neurotoxic and other active compounds in the eggs are believed to play important roles in the eggs' toxic actions.