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1.
Daniel Rohan Phadke Daniel P. Sheeran Luke R. Wilkins John A. Kern Margaret C. Tracci John F. Angle 《Journal of vascular and interventional radiology : JVIR》2019,30(4):572-577
Purpose
To characterize the degree of venous collateralization before and after endovascular therapy and determine the effect of collateralization on success of thrombolysis and rate of repeat intervention in patients with Paget–Schroetter syndrome.Materials and Methods
A single-center retrospective study of 37 extremities in 36 patients (mean age, 32.64 y; range, 15–72 y; 24 men) with PSS treated with endovascular therapy from 2007 through 2017 was conducted. Venograms at presentation, after lysis, postoperatively, and at each repeat intervention were graded for venous stenosis, thrombus burden, and collateralization on a 5-point scale. Collateralization was classified as high-grade (9 extremities) or low-grade (28 extremities) based on grading of the venograms at presentation.Results
Primary technical success rate for endovascular treatment was 100%. Eighty-six percent of patients (32 of 37) underwent thrombolysis, 91% (34 of 37) underwent mechanical thrombectomy, and 83% (30 of 37) underwent balloon angioplasty. Overall primary patency rate was 50% at 12 months. The repeat intervention rate within 12 months was significantly higher for extremities with high- vs low-grade collateralization (89% vs 43%; P = .016). There was a significant decrease in the median grade of collateral severity after initial intervention (2 vs 1; P = .044) and 1 day postoperatively (2 vs 1; P = .040) vs the venogram at presentation.Conclusions
Severity of venous collateralization on the venogram at presentation of patients with PSS does not appear to affect success of endovascular therapy but may predict long-term patency of affected extremities. Patients in this cohort with severe collateralization on presentation were more likely to need repeat intervention. 相似文献2.
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Taylor R. Valentino Kristin J. Stuempfle Marialice Kern Martin D. Hoffman 《Research in sports medicine (Print)》2016,24(3):197-206
It is advised that individuals should avoid losing >2% of their body mass during exercise in order to prevent hyperthermia. This study sought to assess whether a loss of >2% body mass leads to elevations in core temperature during an ultramarathon. Thirty runners agreed to take part in the study. Body mass and core temperature were measured at the start, at three locations during the race and the finish. Core temperature was not correlated with percent body mass change (p = 0.19) or finish time (p = 0.11). Percent body mass change was directly associated with finish time (r = 0.58, p < 0.01), such that the fastest runners lost the most mass (~3.5–4.0%). It appears that a loss of >3% body mass does not contribute to rises in core temperature. An emphasis on fluid replacement for body mass losses of this magnitude during prolonged exercise is not justified as a preventative measure for heat-related illnesses. 相似文献
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Shuo-Hsiu Chang Fangshi Zhu Neel Patel Taimoor Afzal Marcie Kern Gerard E. Francisco 《The journal of spinal cord medicine》2020,43(1):126-129
Context: To investigate the feasibility of combining the lower-limb exoskeleton and body weight unweighing technology for assisted walking in tetraplegia following spinal cord injury (SCI).Findings: A 66-year-old participant with a complete SCI at the C7 level, graded on the American Spinal Injury Association Impairment Scale (AIS) as AIS A, participated in nine sessions of overground walking with the assistance from exoskeleton and body weight unweighing system. The participant could tolerate the intensity and ambulate with exoskeleton assistance for a short distance with acceptable and appropriate gait kinematics after training.Conclusion: This report showed that using technology can assist non-ambulatory individuals following SCI to stand and ambulate with assistance which may promote general physical and psychological health if used in the long term. 相似文献
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- FFR/iFR is discordant in 15–20% of cases, at times causing confusion about revascularization decisions.
- The CONTRAST substudy identifies lesion location, lesion severity, and bradycardia as major predictors for FFR/iFR discordance, with age a minor predictor.
- Each of these predictors can be explained physiologically through the mechanisms related to resting and hyperemic pressure loss across different patterns of atherosclerotic stenoses.
- A logical approach to using both resting and hyperemic pressure ratios is proposed.
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The purpose of this in‐vitro study was to evaluate the influence of the framework design on the durability of inlay‐retained cantilever fixed dental prostheses (IR‐FDPs), made from zirconia ceramic, after artificial ageing. Forty‐eight caries‐free human premolars were prepared as abutments for all‐ceramic cantilevered IR‐FDPs using six framework designs: occlusal–distal (OD) inlay, OD inlay with an oral retainer wing, OD inlay with two retainer wings, mesial–occlusal–distal (MOD) inlay, MOD inlay with an oral retainer ring, and veneer partial coping with a distal box (VB). Zirconia IR‐FDPs were fabricated via computer‐aided design/computer‐aided manufacturing (CAD/CAM) technology. The bonding surfaces were air‐abraded (50 μm alumina/0.1 MPa), and the frameworks were bonded with adhesive resin cement. Specimens were stored for 150 d in a 37°C water bath during which they were thermocycled between 5 and 55°C for 37,500 cycles; thereafter, they were exposed to 600,000 cycles of dynamic loading with a 5‐kg load in a chewing simulator. All surviving specimens were loaded onto the pontic and tested until failure using a universal testing machine. The mean failure load of the groups ranged from 260.8 to 746.7 N. Statistical analysis showed that both MOD groups exhibited significantly higher failure loads compared with the other groups (i.e. the three OD groups and the VB group) and that there was no significant difference in the failure load among the OD groups and the VB group. In conclusion, zirconia IR‐FDPs with a modified design exhibited promising failure modes. 相似文献
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Johanna Buchcik Uta Gaidys Joachim Westenhöfer Katrin Kern Corinna Petersen-Ewert 《Pr?vention und Gesundheitsf?rderung》2018,13(4):345-352