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71.
Identification of metabolites of trenbolone acetate in androgenic runoff from a beef feedlot 总被引:2,自引:0,他引:2
Durhan EJ Lambright CS Makynen EA Lazorchak J Hartig PC Wilson VS Gray LE Ankley GT 《Environmental health perspectives》2006,114(Z1):65-68
Little is known concerning the potential ecological effects of hormonally active substances associated with discharges from animal feeding operations. Trenbolone acetate is a synthetic anabolic steroid that is widely used in the United States to promote growth of beef cattle. Metabolites of trenbolone acetate include the stereoisomers 17alpha- and 17beta-trenbolone, both of which are stable in animal wastes and are relatively potent androgens in fish and mammals. Our purpose in this study was to evaluate the occurrence of 17alpha- and 17beta-trenbolone in a beef cattle feedlot discharge and in river water upstream and downstream from the discharge. In conjunction with that effort, we measured in vitro androgenic activity of the discharge using CV-1 cells that had been transiently cotransfected with human androgen receptor and reporter gene constructs. Samples were collected on nine different occasions during 2002 and 2003. Whole-water samples from the discharge caused a significant androgenic response in the CV-1 cells and contained detectable concentrations of 17alpha- and 17beta-trenbolone. Further work is needed to ascertain the degree to which synthetic androgens such as trenbolone contribute to androgenic activity of feedlot discharges. 相似文献
72.
Carnot Ntafam Adam T. Miller Bryce D. Beutler Judith Bamporiki Ara B. Sahakian Phillip M. Cheng 《Radiology Case Reports》2022,17(10):3504
Schwannomas are common peripheral nerve sheath tumors that typically occur on the head, neck, trunk, or extremities. Intra-abdominal schwannomas, however, are rare. We describe a young woman who presented for imaging evaluation of suspected nephrolithiasis and was incidentally found to have a schwannoma centered within the pancreatic parenchyma. In addition, we detail the clinical, imaging, and histopathologic features of pancreatic schwannoma and summarize diagnosis and management of this rare clinical entity. 相似文献
73.
Phillip G. Popovich Philip J. Horner Bradford B. Mullin Bradford T. Stokes 《Experimental neurology》1996,142(2):258-275
Blood–spinal cord barrier (BSB) permeability was measured using quantitative autoradiography following contusion injury to the rat spinal cord. Permeability was assessed by calculating blood-to-tissue transfer constants (Kivalues) for the vascular tracer [14C]-α-aminoisobutyric acid (AIB) in injured (3, 7, 14, and 28 days postinjury), laminectomy control, and uninjured control animals. Permeability was quantitated using four separate imaging techniques in gray and white matter throughout the rostro-caudal extents of the forming lesion. Away from the epicenter, gray matter permeability was further differentiated within discrete spinal lamina using computerized templates. Regardless of the type of analysis used, increased AIB permeability (Kivalues) was noted at all survival times in all tissue regions with respect to both uninjured and laminectomy control groups. The data indicate a large increase in individualKivalues throughout the dorsoventral axis of the spinal cord at 3 days postinjury (≈6–9 ml/kg/min). By 7 days,Kivalues were quantitatively smaller (≈4–5 ml/kg/min) in all regions compared with 3-day tissues. Despite further attenuation of AIB uptake in the gray matter at 14 and 28 days postinjury, circumferential white matter tracts showed a secondary increase in permeability compared to 7-day tissue. Permeability in the white matter at 14–28 days postinjury (≈5–6 ml/kg/min) was comparable to that at 3 days postinjury (6–7 ml/kg/min). Measurements of the axial distribution of AIB permeability indicate increased BSB permeability over several segments rostral and caudal to the lesion epicenter (≈3 cm in both directions). Secondary elevations of AIB transfer in the spinal white matter between 14 and 28 days were colocalized with zones of immunohistochemically defined microglial clusters. The known plasticity of this cell type in response to changes in the extracellular microenvironment suggests that the spinal white matter at later survival times (14–28 days postinjury) is an area of dynamic vascular and/or axonal reconstruction. The implications of increased permeability to both tissue injury and neural regeneration are discussed. 相似文献
74.
75.
Nancy Rakow Noah Barka Dale Nelson Nan Allen Robyn Gringaard Phillip Falkner 《Journal of investigative surgery》2013,26(3):187-193
Patients born with congenital right ventricular outflow tract lesions are faced with invasive procedures to establish hemodynamic and physiological stability. Commonly, multiple subsequent surgical procedures are required due to deterioration of a previous repair. These procedures carry additive risks of mortality and morbidity. Less aggressive procedures with accompanying lower risk is ideal. Success in percutaneously placing a transcatheter valve has previously been reported; however, continued safety and efficacy of any technique needs continual assessment. We developed a model for preclinical evaluation of a percutaneous placement of a pulmonic transcatheter valve in adult sheep, including preoperative, surgical, and postoperative techniques for long-term evaluation. Adult sheep were assessed and determined to be acceptable for study enrollment. Perioperative antibiotics and analgesics were given prior to a left thoracotomy. A Medtronic, Hancock 1 valve conduit was inserted for reconstruction of the right ventricular outflow tract. The Hancock 1 valve conduit alone represented the control group and the test animals comprised the addition of a Melody? transcatheter pulmonary valve (TPV), within the Hancock 1 valve conduit. Fifteen adult sheep survived the surgical implant procedure with no perioperative mortality. There were four early postoperative deaths, three due to infection and one due to heart failure, secondary to intraoperative heart block. The remaining 11 animals remained healthy, gained weight, and survived to termination at 5 months. An initial definite-sized valve conduit was implanted, followed by inserting a single size TPV, which allowed a more accurate physiological assessment of any chosen valve. Our developed adult sheep model for percutaneous TPV implantation for right ventricular outflow tract lesions was successful for long-term assessment by utilizing our preoperative, surgical, and postoperative techniques. 相似文献
76.
Phillip S. Naimo Tyson A. Fricke Melissa G.Y. Lee Yves d'Udekem Johann Brink Christian P. Brizard Igor E. Konstantinov 《The Journal of thoracic and cardiovascular surgery》2021,161(2):368-375
ObjectiveTo determine the outcomes of patients with a quadricuspid truncal valve (TV) and durability of TV repair.MethodWe reviewed 56 patients with truncus arteriosus and a quadricuspid TV who underwent complete repair between 1979 and 2018.ResultsTV insufficiency was present in 39 patients (mild, n = 22; moderate, n = 14; and severe, n = 3). Fourteen patients had concomitant TV surgery. Early mortality in patients who had concomitant TV surgery was 14% (2 out of 14 patients) and overall survival was 77.1% ± 11.7% at 15 years. Freedom from TV reoperation was 30.3% ± 14.6% at 15 years. Early mortality in patients who did not undergo concomitant TV surgery was 9.5% (4 out of 42 patients) and overall survival was 74.9% ± 6.9% at 15 years. Progression of TV insufficiency requiring TV surgery occurred in 16.7% (7 out of 42 patients). Freedom from TV reoperation was 77.1% ± 7.8% at 15 years. The most common method of repair was tricuspidization of the TV. Freedom from TV reoperation was 64.3% ± 21.0% at 10 years after tricuspidization and 0% at 6 years after other types of TV surgery. Overall follow-up was 97.6% (41 out of 42 patients) complete for survivors with median follow-up of 16.6 years. At last follow-up there was no TV insufficiency in 16 patients, mild insufficiency in 24 patients, and moderate insufficiency in 1 patient.ConclusionsMore than one-third of patients with a quadricuspid TV require TV surgery. Tricuspidization of the quadricuspid TV appears to be a durable repair option with good long-term outcomes. 相似文献
77.
Objective. To implement and assess a pharmacy dermatology and cosmeceutical compounding elective course and its impact on graduates’ careers.Design. A 3-credit elective course that incorporated classroom lectures on ambulatory dermatologic diseases and cosmeceutical products with case studies, weekly quizzes, and a comprehensive business plan project was implemented in a doctor of pharmacy (PharmD) program in 2010.Assessment. Assessment instruments including weekly quizzes, a business plan project, and pre- and post-course tests were used to evaluate course content. Across 3 offerings of the course (2010, 2011, 2012), pre- and post-course test scores improved. Results of a postgraduate survey showed that 54% of respondents worked at a pharmacy offering compounding services, and 57% felt that the course played a significant or very significant role in their counseling on dermatologic conditions.Conclusions. Assessment methods revealed student learning of course content and the course appeared moderately beneficial to graduates’ early careers. A more longitudinal analysis is needed to assess the course’s impact on long-term career choices, particularly those dealing with compounding of cosmeceutical products. 相似文献
78.
Abdulrahman Hamdi Christopher Julien Phillip Brown Ian Woods Anas Hamdi Gezzer Ortega Terrence Fullum Daniel Tran 《Obesity surgery》2014,24(8):1386-1390
Reoperative surgery for the morbidly obese has become increasingly common due to postoperative weight regain. There are limited studies evaluating the effectiveness of revisional surgery. This study evaluates the weight loss outcomes of revisional surgery over a 2-year period at our University Hospital, USA. Of the 412 patients who underwent laparoscopic bariatric surgery between June 2009 and June 2011, we identified 25 patients who had Roux-en-Y gastric bypass (RYGB) originally, who underwent laparoscopic revisional surgery for weight regain. Preoperative and postoperative data were reviewed. Statistical analysis was performed using paired t test. This study includes 0 male and 25 female patients with an average age of 42 (range min to max: 28–58), mean original body mass index (BMI) of 54.6 kg/m2 (r?=?37.3–80.7), average lowest BMI achieved of 32.2 (r?=?20.1–50.9), and average BMI at the time of revision of 41.0 kg/m2 (r?=?29.5–60.7, standard deviation (SD)?=?8.5). All laparoscopic revisions consisted of resizing the gastric pouch by resection and recreating the gastrojejunostomy. Average hospital length of stay was 1.28 days (r?=?1–4). Perioperative morbidity was 8 %; one patient developed a trocar site hernia which required repair, and another suffered postoperative bleeding requiring transfusion. There was no mortality. Postoperative BMI averages at 3, 6, 9, 12, and 24 months were 35.0 (SD?=?7.15), 34.7 (SD?=?4.26), 36.2 (SD?=?7.63), 33.0 (SD?=?6.58), and 44.2 (SD?=?12.87), respectively. Statistically significant weight loss was achieved at 3 [t (10)?=?6.74, p?<?0.05], 6 [t (7)?=?4.69, p?<?0.05], 9 [t (9)?=?2.94, p?<?0.05], and 12 [t (6)?=?3.78, p?<?0.05] months. However, there was no statistically significant weight loss at 24 months postoperatively [t (4)?=??0.16, p?>?0.05]. Laparoscopic revisional bariatric surgery can be performed with significant weight loss up to 1 year postoperatively. However, additional studies are required to evaluate longer-term success. 相似文献
79.
In brief: Many cardiac patients would like to improve their muscle fitness through a program of strength training. Evidence now indicates that such a program, if conducted within a medically supervised rehabilitation program, is both safe and beneficial. This article provides practical guidelines for a strength training program, which may be modified to fit a particular program. The recommendations include criteria for admission, procedures for orientation and instruction, and techniques for supervision. 相似文献
80.
Fadi G. Hage M.D. Phillip Dean M.D. Saleem Raslan M.D. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(1):76-87
Cardiomyopathy refers to a set of diseases that are characterized by myocardial dysfunction. Classically, two-dimensional echocardiography has been used in the diagnosis of these disorders and to help guide their management. Three-dimensional transthoracic echocardiography is now increasingly being used in the diagnosis, management, and prognostication of intrinsic cardiomyopathies. In this article, we summarize the available data on the use of three-dimensional transthoracic echocardiography in various forms of intrinsic cardiomyopathy as well as some of its advantages over traditional two-dimensional transthoracic echocardiography. (Echocardiography 2012;29:76-87) 相似文献