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Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them.  相似文献   
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Cancer Chemotherapy and Pharmacology - CC-486 is an oral formulation of azacitidine that allows for extended dosing schedules to prolong azacitidine exposure to malignant cells and maximize...  相似文献   
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Background: Identification of germline and somatic BRCA1/2 mutations in ovarian cancer is important for genetic counseling and treatment decision making with poly ADP ribose polymerase inhibitors. Unfortunately, data on the frequency of BRCA1/2 mutations in Vietnamese patients are scare. Methods: We aim to explore the occurrence of BRCA1/2 mutations in 101 Vietnamese patients with ovarian cancer including serous (n = 58), endometrioid (n = 14), mucinous (n = 24), and clear cell (n = 5) carcinomas. BRCA1/2 mutations were detected from formalin-fixed parafin-embedded tumor samples using the OncomineTM BRCA Research Assay on Personal Genome Machine Platform with Ion Reporter Software for sequencing data analysis. The presence of pathogenic mutations was confirmed by Sanger sequencing. Results: We found no BRCA2 mutation in the entire cohort. Four types of pathogenic mutations in BRCA1 (Ser454Ter, Gln541Ter, Arg1751Ter, and Gln1779AsnfsTer14) were detected in 8 unrelated patients (7.9%) belonging to serous and endometrioid carcinoma groups. Except for the c.1360_1361delAG (Ser454Ter) mutation in BRCA1 exon 11 that was somatic, the other mutations in exons 11, 20, and 22 were germline.  Interestingly, the recurrent Arg1751Ter mutation in BRCA1 exon 20 appeared in 4 patients, suggesting that this is a founder mutation in Vietnamese patients. Conclusion: Mutational analysis of tumor tissue using next generation sequencing allowed the detection of both germline and somatic BRCA1/2 mutations.  相似文献   
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Zumel-Marne  Angela  Kundi  Michael  Castaño-Vinyals  Gemma  Alguacil  Juan  Petridou  Eleni Th  Georgakis  Marios K.  Morales-Suárez-Varela  Maria  Sadetzki  Siegal  Piro  Sara  Nagrani  Rajini  Filippini  Graziella  Hutter  Hans-Peter  Dikshit  Rajesh  Woehrer  Adelheid  Maule  Milena  Weinmann  Tobias  Krewski  Daniel  ′t Mannetje  Andrea  Momoli  Franco  Lacour  Brigitte  Mattioli  Stefano  Spinelli  John J.  Ritvo  Paul  Remen  Thomas  Kojimahara  Noriko  Eng  Amanda  Thurston  Angela  Lim  Hyungryul  Ha  Mina  Yamaguchi  Naohito  Mohipp  Charmaine  Bouka  Evdoxia  Eastman  Chelsea  Vermeulen  Roel  Kromhout  Hans  Cardis  Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in...  相似文献   
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