Publications by authors named "Kevin Smith"

Imaging of renal trauma.

Radiol Clin North Am

September 2003

Trauma is a major cause of death and disability and renal injuries occur in up to 10% of patients with significant blunt abdominal trauma. Patients with penetrating trauma and hematuria, blunt trauma with shock and hematuria, or gross hematuria warrant imaging of the urinary tract specifically and CT is the preferred modality. If there is significant perinephric fluid, especially medially, or deep laceration, delayed images should be obtained to evaluate for urinary extravasation.

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CT is a robust, rapid means of evaluation for a wide spectrum of urologic disorders. The evaluation of renal trauma, urologic malignancy, urolithiasis, and vascular anatomy is well suited to CT techniques. Subtle adjustments in the technical parameters and timing of the study, however, can optimize the evaluation based on the clinical setting.

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The concentration and glycosylation of alpha(1)-acid glycoprotein (AGP) alter significantly during inflammation. A definitive physiological role for AGP remains elusive and is the subject of extensive investigation. This study investigated the influence of AGP on the activity of collagenase-3, an important mediator of cartilage destruction in rheumatoid arthritis.

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Object: This study was conducted to evaluate peripheral nerve regeneration through a conduit composed of a bioresorbable material (LactoSorb).

Methods: Sprague-Dawley rats weighing approximately 250 g were randomized into five groups. A 20-mm-long sciatic nerve gap was created, then it was bridged by a reverse nerve autograft (Group I), an empty silicone tube (Group II), a silicone tube containing a short (2-mm) interposed nerve segment (Group III), an empty LactoSorb conduit (Group IV), or a LactoSorb conduit containing a 2-mm interposed nerve segment (Group V).

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Gene therapy holds great promise. Somatic gene therapy has the potential to treat a wide range of disorders, including inherited conditions, cancers, and infectious diseases. Early progress has already been made in the treatment of a range of disorders.

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Attempts to sustain a narrow focus of attention over a long period of time are effortful and are punctuated by lapses. Most studies of sustained attention performance obscure the presence and pattern oflapses by reporting measures that are summed across the entire period of an individual's performance, or that are average scores for blocks of trials across many participants. In the present study we attempted to explore fluctuation in the attention of individual participants over the course of a vigilance task and to quantify its periodicity, if any exists.

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The ground- and excited-state metal-ligand dynamics of nonplanar nickel(II) 2,3,5,7,8,10,12,13,15,17,18,20-dodecaphenylporphyrin (NiDPP) and two fluorinated analogues (NiF(20)DPP and NiF(28)DPP) have been investigated using static and time-resolved absorption spectroscopy in toluene and in ligating media that differ in basicity, aromaticity, and steric encumbrance. Because of the electronic and steric consequences of nonplanarity, NiDPP does not bind axial ligands in the ground state, but metal coordination does occur after photoexcitation with multistep dynamics that depend on the properties of the ligand. Following the structural relaxations that occur in all nickel porphyrins within approximately 10 ps, ligand binding to photoexcited NiDPP is progressively longer in pyridine, piperidine, and 3,5-lutidine (25-100 ps) but does not occur at all in 2,6-lutidine in which the ligating nitrogen is sterically encumbered.

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Solution (1)H NMR has been used to elucidate the magnetic properties and electronic structure of the prosthetic group in high-spin, ferrous deoxy myoglobin from the sea hare Aplysia limacina. A sufficient number of dipolar shifted residue signals were assigned to allow the robust determination of the orientation and anisotropy of the paramagnetic susceptibility tensor, chi. The resulting quantitative description of dipolar shifts allows a determination of the contact shifts for the heme.

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Background: Cricoid pressure (CP) is often used during general anesthesia induction to prevent passive regurgitation of gastric contents. The authors used magnetic resonance imaging to determine the anatomic relationship between the esophagus and the cricoid cartilage ("cricoid") with and without CP.

Methods: Magnetic resonance images of the necks of 22 healthy volunteers were reviewed with and without CP.

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The shallow water acoustic communication channel is characterized by strong signal degradation caused by multipath propagation and high spatial and temporal variability of the channel conditions. At the receiver, multipath propagation causes intersymbol interference and is considered the most important of the channel distortions. This paper examines the application of time-reversal acoustic (TRA) arrays, i.

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This thoughtful essay conveys a logically ordered series of concepts that may help develop a process to more fully integrate evidence into healthcare management decisions. In responding to this article we have tried to think broadly about what might be discovered if the ideas of Browman, Snider and Ellis were put into practice. We have chosen to focus on factors that could confound the five-point plan suggested by the authors.

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Epidemiologic studies have shown that airborne particulate matter (PM) with a mass median aerodynamic diameter < 10 microm (PM10) is associated with an increase in respiratory-related disease. However, there is a growing consensus that particles < 2.5 microm (PM2.

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Purpose: Quality of life (QOL) has become an important endpoint in clinical trials and studies of medical interventions for many chronic diseases, but has not been widely studied in the substance abuse field. The purpose of this study was to measure QOL in a large sample of adult substance abusers (SA), to compare QOL ratings with those for other chronic diseases, and to assess factors influencing QOL levels in this population.

Methods: Hour-long personal interviews were administered to 570 randomly selected substance abuse clients in six detoxification centers and seven outpatient facilities in Massachusetts.

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Objective: Pancreatic duct stenting is now recognized as a treatment option for a number of pancreatic disorders. Although stent-induced ductal changes may result, there is little information regarding the frequency of these stent-induced changes in chronic pancreatitis and their relationship to stent occlusion and clinical response. Our objectives were to evaluate pancreatic ductal changes after endoscopic stenting in patients with preexisting radiographic evidence of chronic pancreatitis and to evaluate the relationships between ductal changes, pain response, and stent patency.

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Tamoxifen is administered for the treatment of breast cancer; however resistance to therapy is commonplace. Postulated mechanisms of resistance to tamoxifen include altered pharmacology of the drug, changes in the structure and function of the oestrogen receptor and expression of genes that function to support the growth of cells resistant to tamoxifen. However, binding of drugs to proteins found in the plasma is known to affect the efficacy of drugs and alter their distribution.

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In vitro formation of Hydrogenobacter thermophilus cytochrome c552 has previously been demonstrated (Daltrop, O., Allen, J. W.

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Practice is the repetition of an action to improve its quality. The value of the practice effect is recognized in sports, music, and surgery. The number of times a surgical procedure is performed may have a bearing on how well it is done.

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The purpose of this study was to assess the impact of total shoulder arthroplasty on the self-assessed health status of a large series of patients with glenohumeral osteoarthritis. In 91 patients we were able to compare the 8 quantitative domains of Short Form-36 (SF-36) before surgery and at 30 to 60 months after surgery. These preoperative and postoperative scores were compared with data from an age- and gender-matched control population.

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Background: Rotator cuff tears are among the most common conditions of the shoulder. One of the major difficulties in studying patients with rotator cuff tears is that the clinical expression of these tears varies widely and different practices may have substantially different patient populations. The goals of the present prospective multipractice study were to use patient self-assessment questionnaires (1) to identify some of the characteristics of patients with rotator cuff tears, other than the size of the cuff tear, that are correlated with shoulder function, and (2) to determine whether there are significant differences in these characteristics among patients from the practices of different surgeons.

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Previous studies of 5,10,15,20-tetraarylporphyrins have shown that the barrier for meso aryl-porphyrin rotation (DeltaG++(ROT)) varies as a function of the core substituent M and is lower for a small metal (M = Ni) compared to a large metal (M = Zn) and for a dication (M = 4H(2+)) versus a free base porphyrin (M = 2H). This has been attributed to changes in the nonplanar distortion of the porphyrin ring and the deformability of the macrocycle caused by the core substituent. In the present work, X-ray crystallography, molecular mechanics (MM) calculations, and variable temperature (VT) (1)H NMR spectroscopy are used to examine the relationship between the aryl-porphyrin rotational barrier and the core substituent M in some novel 2,3,5,7,8,10,12,13,15,17,18,20-dodecaarylporphyrins (DArPs), and specifically in some 5,10,15,20-tetraaryl-2,3,7,8,12,13,17,18-octaphenylporphyrins (TArOPPs), where steric crowding of the peripheral groups always results in a very nonplanar macrocycle.

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Previous work suggests that the labrum helps center the humeral head. We hypothesized that detachment of the labrum alone would shift the head from its centered position toward the detachment, and repair would restore its centered position. Five young shoulders were used, and glenoids were potted with the articular surfaces oriented horizontally.

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This report describes a pharmacokinetic study and a clinical study of three different formulations of oral tramadol: once-daily tramadol tablets 150 and 200 mg, and normal release tramadol capsules 50 mg 8-hourly. The randomized, open-label, crossover pharmacokinetic study included 22 subjects. The three treatments showed equivalent mean systemic availability of tramadol.

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