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1.
[Purpose] To assess the effect of 12-weeks Nordic walking training on gait parameters and some elements of postural control. [Subjects and Methods] Sixty-seven women aged 65 to 74 years were enrolled in this study. The subjects were divided into a Nordic Walking group (12 weeks of Nordic walking training, 3 times a week for 75 minutes) and a control group. In both study groups, a set of functional tests were conducted at the beginning and at the end of the study: the Forward Reach Test (FRT) and the Upward Reach Test (URT) on a stabilometric platform, and the analysis of gait parameters on a treadmill. [Results] The NW group showed improvements in: the range of reach in the FRT test and the URT test in compared to the control group. The length of the gait cycle and gait cycle frequency also showed changes in the NW group compared to the control group. [Conclusion] A 12-week NW training program had a positive impact on selected gait parameters and may improve the postural control of women aged over 65 according to the results selected functional tests.Key words: Nordic walking, Postural control, Gait  相似文献   
2.
The objective of the study was to assess the use of maximum (Vmax) and final propulsive phase (FPV) bar velocity to predict jump height in the weighted jump squat. FPV was defined as the velocity reached just before bar acceleration was lower than gravity (-9.81 m·s-2). Vertical jump height was calculated from the take-off velocity (Vtake-off) provided by a force platform. Thirty swimmers belonging to the National Slovenian swimming team performed a jump squat incremental loading test, lifting 25%, 50%, 75% and 100% of body weight in a Smith machine. Jump performance was simultaneously monitored using an AMTI portable force platform and a linear velocity transducer attached to the barbell. Simple linear regression was used to estimate jump height from the Vmax and FPV recorded by the linear velocity transducer. Vmax (y = 16.577x - 16.384) was able to explain 93% of jump height variance with a standard error of the estimate of 1.47 cm. FPV (y = 12.828x - 6.504) was able to explain 91% of jump height variance with a standard error of the estimate of 1.66 cm. Despite that both variables resulted to be good predictors, heteroscedasticity in the differences between FPV and Vtake-off was observed (r2 = 0.307), while the differences between Vmax and Vtake-off were homogenously distributed (r2 = 0.071). These results suggest that Vmax is a valid tool for estimating vertical jump height in a loaded jump squat test performed in a Smith machine.

Key points

  • Vertical jump height in the loaded jump squat can be estimated with acceptable precision from the maximum bar velocity recorded by a linear velocity transducer.
  • The relationship between the point at which bar acceleration is less than -9.81 m·s-2 and the real take-off is affected by the velocity of movement.
  • Mean propulsive velocity recorded by a linear velocity transducer does not appear to be optimal to monitor ballistic exercise performance.
Key words: Linear velocity transducer, force platform, jump performance, swimming  相似文献   
3.
Chronic myeloid leukemia in chronic phase (CML-CP) is induced by BCR-ABL1 oncogenic tyrosine kinase. Tyrosine kinase inhibitors eliminate the bulk of CML-CP cells, but fail to eradicate leukemia stem cells (LSCs) and leukemia progenitor cells (LPCs) displaying innate and acquired resistance, respectively. These cells may accumulate genomic instability, leading to disease relapse and/or malignant progression to a fatal blast phase. In the present study, we show that Rac2 GTPase alters mitochondrial membrane potential and electron flow through the mitochondrial respiratory chain complex III (MRC-cIII), thereby generating high levels of reactive oxygen species (ROS) in CML-CP LSCs and primitive LPCs. MRC-cIII-generated ROS promote oxidative DNA damage to trigger genomic instability, resulting in an accumulation of chromosomal aberrations and tyrosine kinase inhibitor-resistant BCR-ABL1 mutants. JAK2(V617F) and FLT3(ITD)-positive polycythemia vera cells and acute myeloid leukemia cells also produce ROS via MRC-cIII. In the present study, inhibition of Rac2 by genetic deletion or a small-molecule inhibitor and down-regulation of mitochondrial ROS by disruption of MRC-cIII, expression of mitochondria-targeted catalase, or addition of ROS-scavenging mitochondria-targeted peptide aptamer reduced genomic instability. We postulate that the Rac2-MRC-cIII pathway triggers ROS-mediated genomic instability in LSCs and primitive LPCs, which could be targeted to prevent the relapse and malignant progression of CML.  相似文献   
4.
A widely used approach to solving the inverse problem in electrocardiography involves computing potentials on the epicardium from measured electrocardiograms (ECGs) on the torso surface. The main challenge of solving this electrocardiographic imaging (ECGI) problem lies in its intrinsic ill-posedness. While many regularization techniques have been developed to control wild oscillations of the solution, the choice of proper regularization methods for obtaining clinically acceptable solutions is still a subject of ongoing research. However there has been little rigorous comparison across methods proposed by different groups. This study systematically compared various regularization techniques for solving the ECGI problem under a unified simulation framework, consisting of both 1) progressively more complex idealized source models (from single dipole to triplet of dipoles), and 2) an electrolytic human torso tank containing a live canine heart, with the cardiac source being modeled by potentials measured on a cylindrical cage placed around the heart. We tested 13 different regularization techniques to solve the inverse problem of recovering epicardial potentials, and found that non-quadratic methods (total variation algorithms) and first-order and second-order Tikhonov regularizations outperformed other methodologies and resulted in similar average reconstruction errors.  相似文献   
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Flis CM  Connor SE 《European radiology》2005,15(10):2185-2193
Venous malformations (VMs) are non proliferative lesions that consist of dysplastic venous channels. The aim of imaging is to characterise the lesion and define its anatomic extent. We will describe the plain film, ultrasound (US) (including colour and duplex Doppler), computed tomography (CT), magnetic resonance imaging (MRI), conventional angiographic and direct phlebographic appearances of venous malformations. They will be illustrated at a number of head and neck locations, including orbit, oral cavity, superficial and deep facial space, supraglottic and intramuscular. An understanding of the classification of such vascular anomalies is required to define the correct therapeutic procedure to employ. Image-guided sclerotherapy alone or in combination with surgery is now the first line treatment option in many cases of head and neck venous malformations, so the radiologist is now an integral part of the multidisciplinary management team.  相似文献   
8.
The classification, clinical presentation, natural history and imaging appearances of vascular masses of the head and neck are reviewed. The radiological appearances of congenital vascular masses (infantile haemangiomas and other congenital vascular tumours, high-flow and low-flow vascular malformations), acquired vascular masses (benign and malignant tumours, non-neoplastic lesions) and other hypervascular masses are described and illustrated, together with consideration of image-guided interventions.  相似文献   
9.
BACKGROUND: At the Clinical Center of Serbia (CCS), which includes 21 Institutes and 6 Centers, approximately 10% of the total annual budgetary funds is spent on the drugs. During the studied period, it was estimated that 0.5% of the above amount has been spent at the Institute for Otorhinolaryngology and Maxillofacial surgery (Institute for ORL and MFS), Clinical Center of Serbia. The aim of this study was to find out if these antibiotics had been used rationally by the monitoring of antibiotics in relation to the number of inpatients, and by the 5 most frequent diagnoses. METHODS: The authors monitored the three-year consumption of antibiotics for inhospital treated patients during the period 2001-2003. Data were obtained from the itemized quarterly report on the consumption by the Central Pharmacy of the CCS. RESULTS: The results were statistically analyzed and presented in percentages and Defined Daily Dosages (DDD) for each group of the antibiotics. The results were analyzed in accordance with the World Health Organization Recommendations and the Guidelines. CONCLUSION: The authors concluded that antibiotics were adequately used at the Institute for ORL and MFS-CCS. The most commonly used antibiotics for gram-positive infections were those from the penicillin and cephalosporin groups. According to the international trends and recommendations, the selected therapy was rational and the antibiotics consumption was cut down during the observed three-year period. It was a true confirmation that the recommendations for the rational antibiotics consumption had been fruitful (produced good results).  相似文献   
10.
BACKGROUND/AIM: According to the data from immunological, biological and molecular researches, there is a close association between the undifferentiated carcinoma of nasopharyngeal type (UCNT) and Epstein-Barr virus (EBV). To use IgA EA antibody as a serological marker in our patients with nasopharyngeal carcinoma from a clinical viewpoint. METHODS: 91 patients were followed in the period from 1989-1998. In 11 of the patients the antibody titre serum for the early antigen of EBV virus were determinated before the treatement, and in 24 of the patients 3 years after the treatement. There were three control groups of patients: 20 voluntary blood donors, 26 patients with squamocellular laryngeal carcinoma, and 10 patients with squamocellular nasopharyngeal carcinoma. RESULTS: In the group of 11 patients with UCNT before the treatment, the value of anti-EA IgA titre was 31.09, and in the patients after the treatement anti-EA IgA antiody titre was 14.56. In the control groups of patients the results were: in the blood donors 5.00; in the group with the diagnosis of squamocellular laryngeal carcinoma, the titre was 5.00; in the patients with squamocellular nosopharyngeal carcinoma, the titre anti-EA IgA was 5.36. CONCLUSION: These results were statisticly highly significant (p < 0.01). Our research clearly showed that anti-EA IgA EBV marker could be useful in diagnosing, differential diagnosing and prognosing as well.  相似文献   
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