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81.
Fast imaging strategies for mouse kidney perfusion measurement with pseudocontinuous arterial spin labeling (pCASL) at ultra high magnetic field (11.75 tesla) 下载免费PDF全文
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J.C.?BrokmannEmail author R.?Rossaint S.?Bergrath B.?Valentin S.K.?Beckers F.?Hirsch S.?Jeschke M.?Czaplik 《Der Anaesthesist》2015,64(6):438-445
Background
The demographic change and an increasing multimorbidity of patients represent increasing challenges for the adequate prehospital treatment of emergency patients. The incorporation of supplementary telemedical concepts and systems can lead to an improved guideline-conform treatment. Beneficial evidence of telemedical procedures is only known for isolated disease patterns; however, no mobile telemedical concept exists which is suitable for use in the wide variety of different clinical situations.Aim
This article presents a newly developed and evaluated total telemedical concept (TemRas) that encompasses organizational, medical and technical components. The use of intelligent and robust communication technology and the implementation of this add-on system allows the telemedical support of the rescue service for all emergencies.Methods
After development of the telemedical rescue assistance system, which includes organizational, medical and technical components, a telemedical centre and six ambulances in five different districts in North-Rhine Westphalia were equipped with this new tool. During the evaluation phase of 1 year in the routine emergency medical service the rate of complications as well as differences between urban and rural areas were analyzed with respect to different target parameters.Results
Between August 2012 and July 2013 a total of 401 teleconsultations were performed during emergency missions and 24 during secondary interhospital transfers. No complications due to teleconsultation were observed. The mean duration (±SD) of teleconsultations was longer in rural areas than in urban areas with 28.6±12.0?min vs. 25.5±11.1?min (p?<?0.0001). In 63.2?% of these missions administration of medications was delegated to the ambulance personnel (52.0?% urban vs. 73.6?% rural, p?<?0.0001). The severity of ailments corresponded to scores of III and VI in the National Advisory Committee for Aeronautics (NACA) classification.Conclusion
Emergency medical care of patients with support by a telemedical system is technically feasible, safe for the patient and allows medical treatment independent of spatial availability of a physician in different emergency situations.83.
Three‐dimensional imaging and analysis of human cartilage degeneration using Optical Coherence Tomography 下载免费PDF全文
Sven Nebelung Nicolai Brill Ulrich Marx Valentin Quack Markus Tingart Robert Schmitt Björn Rath Holger Jahr 《Journal of orthopaedic research》2015,33(5):651-659
Optical Coherence Tomography (OCT) is an evolving imaging technology allowing non‐destructive imaging of cartilage tissue at near‐histological resolution. This study investigated the diagnostic value of real time 3‐D OCT in comparison to conventional 2‐D OCT in the comprehensive grading of human cartilage degeneration. Fifty‐three human osteochondral samples were obtained from eight total knee arthroplasties. OCT imaging was performed by either obtaining a single two‐dimensional cross‐sectional image (2‐D OCT) or by collecting 100 consecutive parallel 2‐D OCT images to generate a volumetric data set of 8 × 8 mm (3‐D OCT). OCT images were assessed qualitatively according to a modified version of the DJD classification and quantitatively by algorithm‐based evaluation of surface irregularity, tissue homogeneity, and signal attenuation. Samples were graded according to the Outerbridge classification and statistically analyzed by one‐way ANOVA, Kruskal Wallis and Tukey's or Dunn's post‐hoc tests. Overall, the generation of 3‐D volumetric datasets and their multiple reconstructions such as rendering, surface topography, parametric, and cross‐sectional views proved to be of potential diagnostic value. With increasing distance to the mid‐sagittal plane and increasing degeneration, score deviations increased, too. In conclusion, 3‐D imaging of cartilage with image analysis algorithms adds considerable potential diagnostic value to conventional OCT diagnostics. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:651–659, 2015. 相似文献
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De Spiegelaere W Casteleyn C Van den Broeck W Plendl J Bahramsoltani M Simoens P Djonov V Cornillie P 《Journal of vascular research》2012,49(5):390-404
Angiogenesis, i.e. the development and growth of blood vessels, is a major topic of research as it plays an important role in normal development and in various pathologies. Recent evidence revealed the existence of different mechanisms of blood vessel growth, including sprouting and intussusceptive angiogenesis, vascular mimicry, and blood vessel cooption. The latter two have only been observed in tumor growth, but sprouting and intussusceptive angiogenesis also occur in healthy, physiologically growing tissues. Despite this variety of angiogenic mechanisms, most of the current research is focused on the mechanism of sprouting angiogenesis because this mechanism was first described and because most existing experimental models are related to sprouting angiogenesis. Consequently, the mechanism of intussusceptive angiogenesis is often overlooked in angiogenesis research. Here, the mechanism of intussusceptive angiogenesis is reviewed and the current techniques and models for investigating intussusceptive angiogenesis are summarized. In addition, other mechanisms of vascular growth are briefly reviewed. 相似文献
90.
Michelle L Frost PhD Amelia E Moore Musib Siddique Glen M Blake Didier Laurent Babul Borah Ursula Schramm Marie‐Anne Valentin Theodore C Pellas Paul K Marsden Paul J Schleyer Ignac Fogelman 《Journal of bone and mineral research》2013,28(6):1337-1347
The functional imaging technique of 18F‐fluoride positron emission tomography (18F‐PET) allows the noninvasive quantitative assessment of regional bone formation at any skeletal site, including the spine and hip. The aim of this study was to determine if 18F‐PET can be used as an early biomarker of treatment efficacy at the hip. Twenty‐seven treatment‐naive postmenopausal women with osteopenia were randomized to receive teriparatide and calcium and vitamin D (TPT group, n = 13) or calcium and vitamin D only (control group, n = 14). Subjects in the TPT group were treated with 20 µg/day teriparatide for 12 weeks. 18F‐PET scans of the proximal femur, pelvis, and lumbar spine were performed at baseline and 12 weeks. The plasma clearance of 18F‐fluoride to bone, Ki, a validated measurement of bone formation, was measured at four regions of the hip, lumbar spine, and pelvis. A significant increase in Ki was observed at all regions of interest (ROIs), including the total hip (+27%, p = 0.002), femoral neck (+25%, p = 0.040), hip trabecular ROI (+21%, p = 0.017), and hip cortical ROI (+51%, p = 0.001) in the TPT group. Significant increases in Ki in response to TPT were also observed at the lumbar spine (+18%, p = 0.001) and pelvis (+42%, p = 0.001). No significant changes in Ki were observed for the control group. Changes in BMD and bone turnover markers were consistent with previous trials of teriparatide. In conclusion, this is the first study to our knowledge to demonstrate that 18F‐PET can be used as an imaging biomarker for determining treatment efficacy at the hip as early as 12 weeks after initiation of therapy. 相似文献