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991.
Menezes Cristiano Magalhães Alamin Todd Amaral Rodrigo Carvalho Alexandry Dias Diaz Roberto Guiroy Alfredo Lam Khai S. Lamartina Claudio Perez-Contreras Alberto Rivera-Colon Yamil Smith Willian Taboada Nestor Timothy Jake Langella Francesco Berjano Pedro 《European spine journal》2022,31(9):2270-2278
European Spine Journal - Anterior lumbar approaches are recommended for clinical conditions that require interbody stability, spinal deformity corrections or a large fusion area. Anterior lumbar... 相似文献
992.
Although microbubble contrast agents are believed to respond differently under different driving-pressure amplitudes, few studies have been performed to extensively study the pressure-dependence of their properties. In this paper, attenuation coefficients of two contrast agents (Optison and Definity) were measured under different driving-pressure amplitudes using a narrowband incident pulse. The attenuation of both contrast agents was found to increase with increasing driving pressure. Simulations using the Rayleigh, Plesset, Noltingk, Neppiras, Poritsky (RPNNP) equation were performed to study this behavior. Simulation results show that significant harmonic generation at high driving-pressure amplitudes contributes to the higher attenuation. Other possible explanations for this behavior were also examined. Attenuation coefficients of two contrast agents were also measured using a broadband method. The results showed great inconsistency when the center frequency of the incident broadband pulse was changed, indicating that broadband techniques may not be suitable for contrast-agent attenuation measurements. 相似文献
993.
Clinical perspectives in perfusion: neuroradiologic applications 总被引:2,自引:0,他引:2
Imaging of cerebral perfusion, particularly by the dynamic tracking of a bolus of gadolinium-based contrast agent, has emerged from the experimental laboratory and become a routine aspect of neuroradiologic practice. This article discusses the practical implementation of "perfusion" protocols into neuroradiologic examinations, as well as discussing the role of postprocessing and quantitative interpretation in terms of vascular physiology and function. Several key clinical indications are introduced, such as acute cerebral ischemia, chronic vascular disease, and tumors. 相似文献
994.
Guang‐Shing Cheng Katherine E. Selwa Charles Hatt Sundaresh Ram Aleksa B. Fortuna Margaret Guerriero Ben Himelhoch Daniel McAree Timothy C. Hoffman Joseph Brisson Ryan Nazareno Kiernan Bloye Timothy D. Johnson Mats Remberger Jonas Mattsson Dharshan Vummidi Ella E. Kazerooni Vibha N. Lama Stefanie Galban Michael Boeckh Gregory A. Yanik Craig J. Galban 《American journal of transplantation》2020,20(8):2198-2205
Parametric response mapping (PRM) is a novel computed tomography (CT) technology that has shown potential for assessment of bronchiolitis obliterans syndrome (BOS) after hematopoietic stem cell transplantation (HCT). The primary aim of this study was to evaluate whether variations in image acquisition under real‐world conditions affect the PRM measurements of clinically diagnosed BOS. CT scans were obtained retrospectively from 72 HCT recipients with BOS and graft‐versus‐host disease from Fred Hutchinson Cancer Research Center, Karolinska Institute, and the University of Michigan. Whole lung volumetric scans were performed at inspiration and expiration using site‐specific acquisition and reconstruction protocols. PRM and pulmonary function measurements were assessed. Patients with moderately severe BOS at diagnosis (median forced expiratory volume at 1 second [FEV1] 53.5% predicted) had similar characteristics between sites. Variations in site‐specific CT acquisition protocols had a negligible effect on the PRM‐derived small airways disease (SAD), that is, BOS measurements. PRM‐derived SAD was found to correlate with FEV1% predicted and FEV1/ forced vital capacity (R = ?0.236, P = .046; and R = ?0.689, P < .0001, respectively), which suggests that elevated levels in the PRM measurements are primarily affected by BOS airflow obstruction and not CT scan acquisition parameters. Based on these results, PRM may be applied broadly for post‐HCT diagnosis and monitoring of BOS. 相似文献
995.
Marian G. Michaels Ricardo M. La Hoz Lara Danziger-Isakov Emily A. Blumberg Deepali Kumar Michael Green Timothy L. Pruett Cameron R. Wolfe 《American journal of transplantation》2020,20(7):1768-1772
The recent identification of an outbreak of 2019‐ novel Coronavirus is currently evolving, and the impact on transplantation is unknown. However, it is imperative that we anticipate the potential impact on the transplant community in order to avert severe consequences of this infection on both the transplant community and contacts of transplant patients. 相似文献
996.
997.
Bruce D. Beynnon Niccolo Fiorentino Mack Gardner-Morse Timothy W. Tourville James R. Slauterbeck Daniel R. Sturnick Erin C. Argentieri Carl W. Imhauser 《Journal of orthopaedic research》2020,38(4):759-767
Combined injury to the anterior cruciate ligament (ACL) and meniscus is associated with earlier onset and increased rates of post-traumatic osteoarthritis compared with isolated ACL injury. However, little is known about the initial changes in joint structure associated with these different types of trauma. We hypothesized that trauma to the ACL and lateral meniscus has an immediate effect on morphometry of the articular cartilage and meniscus about the entire tibial plateau that is more pronounced than an ACL tear without meniscus injury. Subjects underwent magnetic resonance imaging scanning soon after injury and prior to surgery. Those that suffered injury to the ACL and lateral meniscus underwent changes in the lateral compartment (increases in the posterior–inferior directed slopes of the articular cartilage surface, and the wedge angle of the posterior horn of the meniscus) and medial compartment (the cartilage-to-bone height decreased in the region located under the posterior horn of the meniscus, and the thickness of cartilage increased and decreased in the mid and posterior regions of the plateau, respectively). Subjects that suffered an isolated ACL tear did not undergo the same magnitude of change to these articular structures. A majority of the changes in morphometry occurred in the lateral compartment of the knee; however, change in the medial compartment of the knee with a normal appearing meniscus also occurred. Statement of clinical significance: Knee injuries that involve combined trauma to the ACL and meniscus directly affect both compartments of the knee, even if the meniscus and articular cartilage appears normal upon arthroscopic examination. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:759-767, 2020 相似文献
998.
Emily R. Hunt Alejandro G. Villasanta-Tezanos Timothy A. Butterfield Christian Lattermann Cale A. Jacobs 《Journal of orthopaedic research》2020,38(2):387-392
In conjunction with cartilage breakdown, muscle maladaptation including atrophy and increased fibrosis have been observed in the quadriceps following anterior cruciate ligament (ACL) injury. Previously observed upregulated muscle-related proteins in the synovial fluid following ACL rupture allude to cellular communication between the joint and muscle. Therefore, the purpose of this study was to determine whether muscle-related analytes are differentially expressed in the serum. Sixteen patients with an acute ACL tear participated in this IRB-approved study. Serum was obtained at two different time points at a mean of 6 and 14 days post-injury, and serum was analyzed by a highly multiplexed assay of 1,300 proteins. Pathway analysis using DAVID was performed; genes included met three criteria: significant change between the two study time points using a paired t test, significant change between the two study time points using a Mann–Whitney non-parametric test, and significant Benjamini post hoc analysis. Twelve analytes significantly increased between time points. Proteins chitinase-3-like protein 1 (p = 0.01), insulin-like growth factor binding protein 1 (p = 0.01), insulin-like growth factor binding protein 5 (p = 0.02), renin (p = 0.004), and lymphotoxin alpha 1: beta 2 (p = 0.03) were significantly upregulated in serum following acute ACL injury. The current results confirm the inflammatory pattern previously seen in the synovial fluid thought to play a role in the progression of post-traumatic osteoarthritis after ACL injury, and this data also provides further insights into important communication between the joint and quadriceps group, whose function is important in long term health. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:387-392, 2020 相似文献
999.
Timothy W. R. Doulton Pauline A. Swift Asam Murtaza Indranil Dasgupta 《Seminars in dialysis》2020,33(3):223-235
Hypertension in dialysis patients is extremely common. In this article, we review the current evidence for blood pressure (BP) goals in hemodialysis patients, and consider the effectiveness of interventions by which BP may be lowered, including manipulation of dietary and dialysate sodium; optimization of extracellular water; prolongation of dialysis time; and antihypertensive medication. Although two meta-analyses suggest lowering BP using antihypertensive drugs might be beneficial in reducing cardiovascular events and mortality, there are insufficient rigorously designed trials in hypertensive hemodialysis populations to determine preferred antihypertensive drug classes. We suggest aiming for predialysis systolic BP between 130 and 159 mm Hg, while at the same time acknowledge the significant limitations of the data upon which it is based. We conclude by summarizing current knowledge as regards management of hypertension in the peritoneal dialysis population and make recommendations for future research in this field. 相似文献
1000.
Sachin Teelucksingh MRCS Stephen Schueler FRCS Timothy P. Crowley FRCS Maniram Ragbir FRCS 《Journal of cardiac surgery》2020,35(11):3179-3182
Persistent infection of left ventricular-assisted devices are challenging to treat. We describe a case of a middle-aged man who presented with cardiogenic shock and profound heart failure from sarcoid myocarditis, necessitating the placement of a left ventricular assist device. After recovery of cardiac function, the device was decommissioned but complicated by infection in the implant bed, chest wall, and of the titanium plug left in situ. This to our knowledge is the first report of an infected titanium plug and we describe an option of using a latissimus dorsi flap using its vascularized tissues to treat the infected plug. This is another example where a multidisciplinary approach can yield rewarding results in cases such as these. 相似文献