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The purpose of this study was to analyze upper extremity and core muscle activation when performing push-ups with different suspension devices. Young fit male university students (n = 29) performed 3 push-ups each with 4 different suspension systems. Push-up speed was controlled using a metronome and testing order was randomized. Average amplitude of the electromyographic root mean square of Triceps Brachii, Upper Trapezius, Anterior Deltoid, Clavicular Pectoralis, Rectus Abdominis, Rectus Femoris, and Lumbar Erector Spinae was recorded. Electromyographic signals were normalized to the maximum voluntary isometric contraction (MVIC). Electromyographic data were analyzed with repeated-measures analysis of variance with a Bonferroni post hoc. Based upon global arithmetic mean of all muscles analyzed, the suspended push-up with a pulley system provided the greatest activity (37.76% of MVIC; p < 0.001). Individually, the suspended push-up with a pulley system also provided the greatest triceps brachii, upper trapezius, rectus femoris and erector lumbar spinae muscle activation. In contrast, more stable conditions seem more appropriate for pectoralis major and anterior deltoid muscles. Independent of the type of design, all suspension systems were especially effective training tools for reaching high levels of rectus abdominis activation.

Key Points

  • Compared with standard push-ups on the floor, suspended push-ups increase core muscle activation.
  • A one-anchor system with a pulley is the best option to increase TRICEP, TRAPS, LUMB and FEM muscle activity.
  • More stable conditions such as the standard push-up or a parallel band system provide greater increases in DELT and PEC muscle activation.
  • A suspended push-up is an effective method to achieve high muscle activity levels in the ABS.
Key words: EMG, unstable, core, trunk, exercise  相似文献   
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Primary central nervous system lymphoma (PCNSL), observed among immunocompromised AIDS patients, has not been reported during chemotherapy for acute lymphoblastic leukaemia (ALL). We report a case of PCNSL occurring in a child receiving intensive multiagent chemotherapy for B-cell ALL. In situ hybridization studies demonstrated Epstein-Barr virus genome in both tumours, suggesting a possible link between the two diseases. The clinical response of the PCNSL to conservative therapy highlights the importance of accurately diagnosing such EBV-related disorders, especially in patients where immune compromise can be reversed.  相似文献   
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We evaluated the clinical response to low-dose etoposide in relapsed acute lymphoblastic leukemia (ALL). Of the 45 patients with ALL in first bone marrow relapse enrolled on the ALL R15 protocol, 44 had received epipodophyllotoxins during frontline therapy. In the first week of remission induction therapy, patients received etoposide (50 mg/m(2) per day) administered orally as a single agent once or twice daily. On Day 8, patients started to receive dexamethasone, vincristine, and L-asparaginase. Etoposide was administered until Day 22. Two courses of consolidation therapy were followed by continuation therapy or hematopoietic stem cell transplantation. After 7 days of single-agent etoposide treatment, peripheral blast cell counts (P=0.013) and percentages of bone marrow blasts (P=0.016) were significantly reduced. In all, 38 (84.4%) attained second remission. Only time to relapse was significantly associated with outcome (P=0.025): the 5-year event-free survival estimates (+/-se) were 52.0+/-9.6% for those with late relapse and 20.0+/-8.0% for those with early relapse. We conclude that low-dose etoposide administered orally has a cytoreductive effect in relapsed ALL.  相似文献   
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The t(9;11)(p21;q23) has been associated with characteristic clinical features and a superior treatment outcome in previously untreated pediatric acute myeloblastic leukemia (AML), but has not been well studied in children with secondary AML. This translocation was detected in 6.7% of de novo and 46% of secondary AML patients treated at St Jude Children's Research Hospital over an 11-year period. Clinical, immunophenotypic, and morphologic characteristics were examined for the cases of t(9;11) secondary AML (n = 12) and compared with findings for children with t(9;11) de novo AML (n = 12). Patients with t(9;11) secondary AML were older at diagnosis, had higher hemoglobin levels, and central nervous system leukemia or hepatosplenomegaly was less frequent. These differences probably reflect survival of the first malignancy and close clinical scrutiny during post-treatment follow-up. Whereas the t(9;11)(p21;q23) occurred exclusively in the French-American-British (FAB) M5 subtype in de novo AML, the FAB M0 and M4 subtypes were also represented in secondary cases. The complete remission rate was somewhat higher for the de novo AML group (91 vs 58%; p = 0.16); their event-free survival was clearly superior to that for children with t(9;11) secondary AML (p = 0.003). Host differences related to the previous malignancy or its treatment could explain the poorer clinical outcome for patients with t(9;11) secondary AML. Alternatively, there could be critical differences at the translocation site or additional, hidden molecular events, that explain the different outcomes.  相似文献   
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叶表面角质层对草珊瑚生药鉴定的意义   总被引:4,自引:0,他引:4  
本文用扫描电镜对草珊瑚Sarcandra glabra(Thunb.)Nakai叶表角质层进行了研究,发现不同产地和同株不同发育程度草珊瑚叶表角质层雕纹型式均有一些差异。  相似文献   
60.
From January 1962 to July 1988, 34 infants less than 29 days of age who had cancer were seen at St. Jude Children's Research Hospital (SJCRH). The malignancies in this group consisted of 19 neuroblastomas, 6 leukemias, 3 retinoblastomas, 2 Wilms' tumors, 2 melanomas, and 2 teratomas. Twenty-three patients (68%) are alive and free of disease 2 months to 24 years after diagnosis. We reviewed the presentation and initial symptoms, pathology reports, patient population, associated anomalies, potential genetic influences, and possible perinatal factors. The most common initial symptom was an enlarging abdomen or abdominal mass. Pathological findings were occasionally difficult to interpret; five additional infants who were referred to us did not have malignancies. There was no increased incidence of associated anomalies or perinatal insults. The only genetic factor was retinoblastoma in one parent of each infant diagnosed as having retinoblastoma. The possible etiology of neonatal tumors is discussed.  相似文献   
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