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1.
Discordant Electrocardiogram Left Ventricular Wall Thickness and Strain Findings in Influenza Myocarditis 下载免费PDF全文
Nael Hawwa M.D. Zoran B. Popovic M.D. Ph.D. Hussain A. Isma'eel M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(12):1880-1884
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain. 相似文献
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Objectives
Iatrogenic injury of the Profunda Femoris Artery (PFA) at time of hip fixation surgery can increase morbidity and mortality and prolong the hospital stay. This is an injury that tends to pass unnoticed as a cause of postoperative deterioration despite being frequently reported in the literature. Our study aims to describe the anatomy of the PFA in relation to the medial femoral cortex with specific emphasis on its orientation relative to the position of a sliding hip screw side plate construct. By doing so we are able to present clear guidance to orthopaedic surgeons on how to avoid iatrogenic PFA injury at the time of hip fracture fixation.Methods
Using Computed Tomography Angiographic (CTA) studies, the course of the PFA in relation to the medial femoral cortex was traced in 44 patients (28 males and 16 females) with mean age of 65.6 years. Coronal and axial CT sections were cross-linked to specify the position of the PFA at 1?cm intervals.Results
The course of the artery could be divided into three parts relative to a fixed reference point. Proximal and distal parts of the artery were in a safer position in comparison to the middle part of the artery that was found very close to the femoral cortex and along the coronal axis of the femur (mean angle 2.9° from the femoral coronal axis and 13.8?mm from the medial femoral cortex). Using the commercially available side plate constructs, this part of the artery corresponded to the distal part of the plate (third and fourth holes).Conclusion
Special attention needs to be practiced by the operating surgeon while drilling into the third and fourth holes of the side plate. 相似文献4.
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INTRODUCTIONThemicrotubule-associatedprotein蚲ishyperphos-phorylatedandglycosylatedinAlzheimerdisease(AD),andtheseabnormalmodificationsformedthebasisofprogressivelyretrogradeneurofibrillarydegenerationseeninADbrainandtherebythedementia(1,2).ADab-normallyphosphorylated蚲notonlyismicrotubuleas-semblyincompetent,butalsoinhibitsassemblyanddis-assemblesthepreassembledmicrotubulesinvitro(3).Inthetangle-bearingneuronsinADbrain,thenormalcytoskeletonisdisruptedandreplacedwi… 相似文献
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Mozammil Hussain Raghu N. Natarajan Amir H. Fayyazi Brian R. Braaksma Gunnar B.J. Andersson Howard S. An 《The spine journal》2009,9(12):1016-1023
Background contextAnterior corpectomy and reconstruction with bone graft and a rigid screw-plate construct is an established procedure for treatment of cervical neural compression. Despite its reliability in relieving symptoms, there is a high rate of construct failure, especially in multilevel cases.PurposeThere has been no study evaluating the biomechanical effects of screw angulation on construct stability; this study investigates the C4–C7 construct stability and load-sharing properties among varying screw angulations in a rigid plate-screw construct.Study designA finite element model of a two-level cervical corpectomy with static anterior cervical plate.MethodsA three-dimensional finite element (FE) model of an intact C3–T1 segment was developed and validated. From this intact model, a fusion model (two-level [C5, C6] anterior corpectomy) was developed and validated. After corpectomy, allograft interbody fusion with a rigid anterior screw-plate construct was created from C4 to C7. Five additional FE models were developed from the fusion model corresponding to five different combinations of screw angulations within the vertebral bodies (C4, C7): (0°, 0°), (5°, 5°), (10°, 10°), (15°, 15°), and (15°, 0°). The fifth fusion model was termed as a hybrid fusion model.ResultsThe stability of a two-level corpectomy reconstruction is not dependent on the position of the screws. Despite the locked screw-plate interface, some degree of load sharing is transmitted to the graft. The load seen by the graft and the shear stress at the bone-screw junction is dependent on the angle of the screws with respect to the end plate. Higher stresses are seen at more divergent angles, particularly at the lower level of the construct.ConclusionThis study suggests that screw divergence from the end plates not only increases load transmission to the graft but also predisposes the screws to higher shear forces after corpectomy reconstruction. In particular, the inferior screw demonstrated larger stress than the upper-level screws. In the proposed hybrid fusion model, lower stresses on the bone graft, end plates, and bone-screw interface were recorded, inferring lower construct failure (end-plate fractures and screw pullout) potential at the inferior construct end. 相似文献
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S A Hussain 《International surgery》1990,75(1):61-62
Because of rich anastomotic network profunda femoris artery is an important link between iliac and superficial femoral/popliteal circulation and thus isolated insufficiency of profunda is rare. It happened in the case reported herein when patient's own native common femoral artery and its bifurcation was excluded by aorto-femoral and femoro-popliteal bypass graft. Revasculatization of profunda ameliorated the problem. 相似文献