71 research outputs found
M-mode echovenography: a new technique for the evaluation of venous wall and valve motion
The M-mode technique which is widely used in echocardiography allows continuous recording of spontaneous venous wall movements. Compliance of the vein can be quantified. The diameter of the normal vein changes with respiration, while only minor changes are induced by cardiac function. Distensibility and compressibility of the common femoral vein (CFV) were documented. During Valsalva manoeuvre the mean diameter of the CFV increased from 1.05(SD 0.18) cm to 1.52(0.25) cm (p<0.01) in the recumbent position and from 1.50(0.20) cm to 1.63(0.17) cm (NS) in the upright position. A patent vein can be completely compressed by the scan head, a thrombosed vein is incompressible. The valve of the normal subclavian vein describes a characteristic M-shaped tracing. The waveform is modulated by cardiac and respiratory function. The study of venous wall movement and venous valve motion provides new insights into venous physiolog
A new rotational thrombectomy catheter: System design and first clinical experiences
Purpose: To describe a new catheter for the percutaneous mechanical removal of fresh and organized thrombi, and to assess its efficacy and safety in vitro and in vivo. Methods: The catheter consists of a coated stainless steel spiral that rotates at 40,000 rpm over a guidewire inside the whole length of an 8 Fr, single-lumen, polyurethane catheter, driving a dual-blade cutting crown. Abraded occlusion material is sucked into the catheter head through distal side holes and transported by the spiral into a reservoir at the proximal end. The efficacy of the device was tested in arterial models and fresh bovine carotid arteries (n=72). In a clinical pilot study 10 patients (8 women, 2 men; mean age 70.6 ±10.1 years) with occlusions of the superficial femoral artery (2-12 cm, mean 5.8 cm), not older than 4 weeks, underwent thrombectomy with the new catheter. Results: In arterial models and bovine cadaver arteries the catheter completely removed fresh thrombi. Occlusion material of higher consistency was cut into particles of 100-500 μm and transported outside. Thrombectomy was successful and vessel patency restored in all 10 patients. The ankle/brachial pressure index significantly (p<0.0005) increased from 0.41±0.18 before intervention to 0.88±0.15 after 48 hr and to 0.84±0.20 after 3 months. Two reocclusions occurred within 14 days after the intervention. Conclusion: Thrombectomy with the new device appears to be feasible and safe in patients with acute and subacute occlusions of the femoropopliteal arter
The effects of creatine pyruvate and creatine citrate on performance during high intensity exercise
<p>Abstract</p> <p>Background</p> <p>A double-blind, placebo-controlled, randomized study was performed to evaluate the effect of oral creatine pyruvate (Cr-Pyr) and creatine citrate (Cr-Cit) supplementation on exercise performance in healthy young athletes.</p> <p>Methods</p> <p>Performance during intermittent handgrip exercise of maximal intensity was evaluated before (pretest) and after (posttest) 28 days of Cr-Pyr (5 g/d, n = 16), Cr-Cit (5 g/d, n = 16) or placebo (pla, 5 g/d, n = 17) intake. Subjects performed ten 15-sec exercise intervals, each followed by 45 sec rest periods.</p> <p>Results</p> <p>Cr-Pyr (p < 0.001) and Cr-Cit (p < 0.01) significantly increased mean power over all intervals. Cr-Cit increased force during the first and second interval (p < 0.01) compared to placebo. The effect of Cr-Cit on force decreased over time and the improvement was not significant at the sixth and ninth interval, whereas Cr-Pyr significantly increased force during all intervals (p < 0.001). Cr-Pyr (p < 0.001) and Cr-Cit (p < 0.01) resulted in an increase in contraction velocity, whereas only Cr-Pyr intake significantly (p < 0.01) increased relaxation velocity. Oxygen consumption measured during rest periods significantly increased with Cr-Pyr (p < 0.05), whereas Cr-Cit and placebo intake did not result in significant improvements.</p> <p>Conclusion</p> <p>It is concluded that four weeks of Cr-Pyr and Cr-Cit intake significantly improves performance during intermittent handgrip exercise of maximal intensity and that Cr-Pyr might benefit endurance, due to enhanced activity of the aerobic metabolism.</p
The effect of phosphatidylserine on golf performance
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Recommended from our members
Refining the accuracy of validated target identification through coding variant fine-mapping in type 2 diabetes.
We aggregated coding variant data for 81,412 type 2 diabetes cases and 370,832 controls of diverse ancestry, identifying 40 coding variant association signals (P < 2.2 × 10-7); of these, 16 map outside known risk-associated loci. We make two important observations. First, only five of these signals are driven by low-frequency variants: even for these, effect sizes are modest (odds ratio ≤1.29). Second, when we used large-scale genome-wide association data to fine-map the associated variants in their regional context, accounting for the global enrichment of complex trait associations in coding sequence, compelling evidence for coding variant causality was obtained for only 16 signals. At 13 others, the associated coding variants clearly represent 'false leads' with potential to generate erroneous mechanistic inference. Coding variant associations offer a direct route to biological insight for complex diseases and identification of validated therapeutic targets; however, appropriate mechanistic inference requires careful specification of their causal contribution to disease predisposition
First Interferometric Trials with the Airborne Digital-Beamforming DBFSAR System
The Microwaves and Radar Institute of the German Aerospace Center (DLR) is known for its consistent work on the field of airborne Synthetic Aperture Radar and its application. Currently, the Institute is developing a new advanced airborne SAR system, the DBFSAR, which is planned to supplement its operational F-SAR system in near future. The development of DBFSAR was triggered by the various evolving digital beamforming (DBF) techniques for future space-borne SAR systems and the need for an airborne experimental platform for preparation of such missions. Additionally, there is a demand for very high resolution SAR imagery, which cannot anymore be fully satisfied with the existing F-SAR system. This paper should give an overview over the current status and performance of the DBFSAR system, including interferometirc results from test flights performed in spring 2017
Acute mountain sickness.
Acute mountain sickness (AMS) is a clinical syndrome occurring in otherwise healthy normal individuals who ascend rapidly to high altitude. Symptoms develop over a period ofa few hours or days. The usual symptoms include headache, anorexia, nausea, vomiting, lethargy, unsteadiness of gait, undue dyspnoea on moderate exertion and interrupted sleep. AMS is unrelated to physical fitness, sex or age except that young children over two years of age are unduly susceptible. One of the striking features ofAMS is the wide variation in individual susceptibility which is to some extent consistent. Some subjects never experience symptoms at any altitude while others have repeated attacks on ascending to quite modest altitudes. Rapid ascent to altitudes of 2500 to 3000m will produce symptoms in some subjects while after ascent over 23 days to 5000m most subjects will be affected, some to a marked degree. In general, the more rapid the ascent, the higher the altitude reached and the greater the physical exertion involved, the more severe AMS will be. Ifthe subjects stay at the altitude reached there is a tendency for acclimatization to occur and symptoms to remit over 1-7 days
Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo
Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201
- …