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991.
Free fatty acids are associated with obesity, insulin resistance, and atherosclerosis in renal transplant recipients 总被引:3,自引:0,他引:3
Armstrong KA Hiremagalur B Haluska BA Campbell SB Hawley CM Marks L Prins J Johnson DW Isbel NM 《Transplantation》2005,80(7):937-944
BACKGROUND: Insulin resistance (IR) may be implicated in the pathogenesis of atherosclerosis in renal transplant recipients (RTRs) and be contributed to, in part, by free fatty acids (FFAs), produced in excess in centrally obese individuals. The aim of this study was to determine the prevalence of IR and the relationships between FFAs, central obesity, and atherosclerosis in a cohort of prevalent RTRs. METHODS: Observational data were collected on 85 RTRs (mean age 54 years; 49% male, 87% Caucasian). Fasting serum was analyzed for FFAs, glucose, and insulin; IR was calculated using the homeostasis model assessment (HOMA-IR) score. Vascular structure was assessed by carotid intima-media thickness (IMT) measurement. Linear regression analyses were performed to determine the factors associated with IR and atherosclerosis. RESULTS: IR occurred in 75% of RTRs, and FFA levels were independently associated with its occurrence (beta: -0.55, 95% CI: -1.02 to -0.07, P = 0.02). Other variables independently associated with IR were male sex, body mass index, central obesity, diabetes, systolic blood pressure and corticosteroid use. There was a significant correlation between FFA levels and IMT (r = 0.3, P=0.01). On multivariate analysis, IMT correlated with elevated FFA (beta: 0.07, 95% CI: 0.02-0.12, P = 0.007), diabetes mellitus (P = 0.05), older age (P < 0.002), and a body mass index >25 kg/m (P = 0.002). CONCLUSIONS: FFAs are associated with the development of IR and may be involved in the pathogenesis of atherosclerosis in RTRs. Additional studies are required to explore these associations further before considering whether an interventional trial aimed at lowering FFA would be a worthwhile undertaking. 相似文献
992.
993.
Perlick L Tingart M Wiech O Beckmann J Bäthis H 《Journal of pediatric orthopedics》2005,25(2):167-170
In slipped capital femoral epiphysis (SCFE), cannulated screw fixation is a standard procedure. The aim of this study was to investigate the feasibility of a fluoroscopy-supported navigation system for screw fixation in SCFE. Using a fluoroscopy-enhanced navigation system, a cannulated screw fixation was performed in seven hips of four patients. The navigation system showed a high feasibility in instrument visualization and implant placing. The mean x-ray time was 6.2 seconds. Initial experiences are very promising and show advantages of the fluoroscopy-supported navigation. Considerably reduced x-ray exposure for patients and surgeons is possible. In the future, further efforts will be necessary to develop navigation-specific instruments to enhance the precision of screw positioning. 相似文献
994.
Hoffend J Mier W Schuhmacher J Schmidt K Dimitrakopoulou-Strauss A Strauss LG Eisenhut M Kinscherf R Haberkorn U 《Nuclear medicine and biology》2005,32(3):287-292
Investigations into tumor angiogenesis and antiangiogenic treatment have renewed interest in tumor perfusion. To image tumor blood-pool by PET, suitable tracers are not generally available. In this experimental study, we characterized a 68Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugate of rat serum albumin (68Ga-DOTA-RSA) in vivo using a generator-produced isotope. Biodistribution was determined in ACI rats after intravenous administration of 3-6 MBq of 68Ga-DOTA-RSA. Three ACI rats were imaged over 1 h by dynamic PET after intravenous administration of 15-25 MBq of 68Ga-DOTA-RSA while the blood-pool activity was recorded simultaneously in a closed extracorporeal loop (ECL) between the carotid artery and the jugular vein. Time-activity curves (TACs) were obtained from volume of interest (VOI) analysis and from the ECL data. Stability and metabolites in plasma and urine were analyzed by size exclusion HPLC (SE-HPLC) 1 h after intravenous injection of 67Ga-DOTA-RSA. Blood radioactivity decreased by 10% and 18% from 10 to 60 min p.i. by biodistribution and PET or ECL, respectively. Tissue sampling between 10 and 60 min p.i. showed slight increases in the uptake of spleen, myocardium, kidney and skeletal muscle while hepatic accretion remained unchanged. Total urinary excretion after 60 min amounted to 9% of the injected dose. HPLC demonstrated a single urinary metabolite corresponding in size to gallium-labeled DOTA. 68Ga-DOTA-RSA is a blood-pool tracer whose physical and biological half-life is well suited for PET. Our findings support clinical imaging using 68Ga-DOTA-labeled human serum albumin (HSA). The generator-produced label makes 68Ga-DOTA-labeled albumin continuously available even to centers lacking an in-house cyclotron. 相似文献
995.
Schneider P Biko J Hänscheid H Hilliger S Koutsampelas C Kranzfelder M Ladner S Reiners C 《European journal of nuclear medicine and molecular imaging》2005,32(7):788-793
Purpose In a prospective randomised study, we investigated the influence of the route of administration of radioiodide on dosimetry and therapy outcome.Methods Fifty-four patients suffering from Graves disease (GD) and 60 patients with unifocal autonomy (UA) participated in the study and were randomly treated with either orally or intravenously administered radioiodide. Pretherapeutic dosimetry was based on single uptake measurements with a calibrated uptake probe system. The radioiodine kinetics during hospitalisation was assessed by daily bedside uptake measurements. Therapeutic dose was determined by half-life and thyroid uptake at the time of discharge using the same uptake probe as for the radioiodine test.Results No improvement in accuracy of dosimetry was achieved when radioiodide was administered intravenously. Mean therapeutic doses were identical following intravenous or oral administration. Variation in the achieved dose was slightly higher in the patients receiving oral administration, this being attributable to larger deviations in discrete activities of the capsules administered as compared with the values determined by dosimetry. No differences according to treatment modality were found with regard to therapeutic outcome. Eighty-seven patients attended 6-month follow-up after therapy. In the UA group, successful treatment, defined as a normal or elevated TSH level, was observed in 94% of patients after oral administration and in 80% after intravenous administration; corresponding figures in the GD group were 68% and 65%.Conclusion The causes of individual differences between targeted and therapeutically achieved doses remain undetermined. Variations in the bioavailability of radioiodide or other parameters affecting thyroid status may be involved, and further investigations are needed to clarify this. 相似文献
996.
Cellular, Histomorphologic, and Clinical Characteristics of a New Octyl-2-Cyanoacrylate Skin Adhesive 总被引:3,自引:0,他引:3
Short-chained cyanoacrylates have been used for many years for topical skin closure. Toxic effects in cell culture of a new long-chained octyl-2-cyanoacrylate tissue adhesive are compared with those of short-chained ethyl-2- and butyl-2-cyanoacrylates. Two cellular tests were used: the agar overlay test and the MTT test. An in vitro test using copper plates coated with the three types of cyanoacrylates serves for evaluating the stability of polymerized skin adhesives. Bilateral neck skin incisions in Goettingen miniature pigs were glued on one side with Dermabond. On the other side, conventional sutures were applied. After the pigs were killed, the resulting skin samples were tested for the tensile strength of their wound stability. Samples of pig dermis were exemplarily and histomorphologically characterized. A clinical examination after submandibular lymph node dissection should examine the application in humans. Cell culture tests were used to show the toxic effects of the three cyanoacrylates. In a copper test, octyl-2-cyanoacrylate was more stabile than ethyl- and butyl-cyanoacrylates. Breaking strength was 30% lower 28 days after operation with the new product than with sutures. In electron microscopy, octyl-2-cyanoacrylate showed no disadvantages with regard to tissue regeneration and no histotoxicity. For plastic surgery, this new topical skin adhesive is a real alternative with attractive results, as compared with conventional suture. 相似文献
997.
998.
999.
Justus Lieber Alexander Joeris Peter Knorr Johannes Schalamon Peter P. Schmittenbecher 《European Journal of Trauma》2005,31(1):3-11
Abstract
Background and Purpose:
Elastic stable intramedullary nailing (ESIN) is well established for stabilizing pediatric forearm fractures. To prevent uncritical use, it is necessary to evaluate the problems and complications of this common technique.
Patients and Methods:
Four pediatric surgical departments participated in a retrospective study analyzing the last 400 fractures treated with ESIN. Continuous documentation of treatment, postoperative course and follow-up formed the basis of evaluation. In this article forearm fractures (n = 163, 40.7%) are discussed, and epidemiology, indication, fracture types, intraoperative technique, postoperative management and problems, as well as complications and results are compared to those described in the literature.
Results:
Complete, transverse fractures of the midshaft (73%) were mainly seen. Indication for intervention was an intolerable axial deviation (85.9%). Intraoperative technique (operating and transillumination time, site of approach, material choice) and postoperative management (hospital stay, number of X-ray controls, and follow-up) differed highly depending on the hospitals circumstances. Postoperatively, 3.0% of patients showed soft-tissue irritation due to sharp nail ends or wound infections. Complications (10.4%) included secondary rupture of a tendon in 3.7%, refracture with nails in situ in 2.5%, axial deviations > 10° or instability of osteosynthesis in 1.8%, delayed healing in 1.2%, migration of nails in 0.6%, and technical failure in 0.6%. Overall, a significant functional restriction (limitation of movement > 10°) was found in three cases only (1.8%) following radial neck fracture.
Conclusion:
ESIN in pediatric forearm fractures is an often used technique with clear indications and excellent results to be expected. Numerically, complications have not altered considerably, but they rather show a shifting of problems with optimization and refinement of technique and improvement of equipment. Thus, continuous evaluation of technical principles and procedural recommendations constitutes the mainstay in the prevention of problems and complications. 相似文献
1000.
Current practice patterns in urologic management of upper-tract transitional-cell carcinoma 总被引:4,自引:0,他引:4
Razdan S Johannes J Cox M Bagley DH 《Journal of endourology / Endourological Society》2005,19(3):366-371
PURPOSE: To determine the current practice patterns in the management of upper-tract transitional-cell carcinoma (TCC) among a large group of urologists. MATERIALS AND METHODS: A survey was sent to 220 practicing members of the Society of Urologic Oncology (SUO) and the Endourological Society (ES) and members of the American Urological Association who did not belong to either society. The survey consisted of 16 focused questions pertaining to the surveillance and management of upper-tract TCC. The responses were used to create a database, which was then analyzed to determine practice trends. RESULTS: Eighty-four of the urologists responded, for a response rate of 38%. Fourteen responses were excluded because of multiple answers to a given question, so 70 were included in the final analysis. Eighty percent of the respondents were in academic practice. A CT urogram was the favored initial procedure for diagnosis of upper-tract TCC and an intravenous urogram was the next commonest choice (53% and 40%, respectively). Ureterorenoscopy was the surveillance tool of choice (70%) after conservative treatment of upper- tract TCC. Laparoscopic nephroureterectomy was the preferred procedure (73%) for a high-grade, large renal-pelvic TCC. Twenty-one percent of the endourologists recommended ureteroscopic ablation for a high-grade, large distal ureteral tumor. This was in sharp contrast to 77% of the respondents who favored a distal ureterectomy for the same clinical scenario. CONCLUSIONS: This study confirms that most urologists treating upper-tract TCC follow the principles reported in the published literature regarding the management of these patients. Further, most urologists, regardless of society affiliations or years in practice, favor minimally invasive techniques for the management of upper-tract TCC. This information may be useful in formulating clear guidelines for the management of this disease. 相似文献