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61.
A commercially available (Syva Co.) enzyme-multiplied immunoassay technique (EMIT) for the quantitative determination of procainamide (PA) and N-acetylprocainamide (NAPA) was modified to allow automated quantitative analysis of approximately 100 samples per day, in a working range of 0.1 to 2.0 micrograms/mL. Such a test was needed to evaluate the pharmacokinetic characteristics of controlled-release dosage forms characterized by long half-lives at low plasma concentration. Analytical recovery of PA and NAPA from serum, plasma, and urine was satisfactory, but at extreme ratios for PA:NAPA the accuracy of determining the lower-concentration component became unsatisfactory. In fact, however, we found no such ratios in 5400 clinical samples assayed by this procedure. 相似文献
62.
Christopher L. Knight MD Henry A. Sakowski MD Bruce L. Houghton MD Mary B. Laya MD MPH Dawn E. DeWitt MD MSc 《Journal of general internal medicine》2004,19(5P2):594-598
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers. 相似文献
63.
Ivan Tkác Pierre-Gilles Henry Peter Andersen C Dirk Keene Walter C Low Rolf Gruetter 《Magnetic resonance in medicine》2004,52(3):478-484
An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models. 相似文献
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66.
Michael R Zalutsky David A Reardon Gamal Akabani R Edward Coleman Allan H Friedman Henry S Friedman Roger E McLendon Terence Z Wong Darell D Bigner 《Journal of nuclear medicine》2008,49(1):30-38
alpha-Particle-emitting radionuclides, such as (211)At, with a 7.2-h half-life, may be optimally suited for the molecularly targeted radiotherapy of strategically sensitive tumor sites, such as those in the central nervous system. Because of the much shorter range and more potent cytotoxicity of alpha-particles than of beta-particles, (211)At-labeled agents may be ideal for the eradication of tumor cells remaining after surgical debulking of malignant brain tumors. The main goal of this study was to investigate the feasibility and safety of this approach in patients with recurrent malignant brain tumors. METHODS: Chimeric antitenascin monoclonal antibody 81C6 (ch81C6) (10 mg) was labeled with 71-347 MBq of (211)At by use of N-succinimidyl 3-[(211)At]astatobenzoate. Eighteen patients were treated with (211)At-labeled ch81C6 ((211)At-ch81C6) administered into a surgically created resection cavity (SCRC) and then with salvage chemotherapy. Serial gamma-camera imaging and blood sampling over 24 h were performed. RESULTS: A total of 96.7% +/- 3.6% (mean +/- SD) of (211)At decays occurred in the SCRC, and the mean blood-pool percentage injected dose was < or = 0.3. No patient experienced dose-limiting toxicity, and the maximum tolerated dose was not identified. Six patients experienced grade 2 neurotoxicity within 6 wk of (211)At-ch81C6 administration; this neurotoxicity resolved fully in all but 1 patient. No toxicities of grade 3 or higher were attributable to the treatment. No patient required repeat surgery for radionecrosis. The median survival times for all patients, those with glioblastoma multiforme, and those with anaplastic astrocytoma or oligodendroglioma were 54, 52, and 116 wk, respectively. CONCLUSION: This study provides proof of concept for regional targeted radiotherapy with (211)At-labeled molecules in oncology. Specifically, the regional administration of (211)At-ch81C6 is feasible, safe, and associated with a promising antitumor benefit in patients with malignant central nervous system tumors. 相似文献
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68.
PURPOSE: To review the effects of the long QT syndrome (LQTS) in the parturient and the current anesthetic management of patients with LQTS. SOURCE: Relevant articles were obtained from a MEDLINE search spanning the years 1980-2006 and a PubMed search spanning the years 1949-2006. Bibliographies of retrieved articles were searched for additional articles. PRINCIPAL FINDINGS: The prevalence of LQTS in the developed world is one per 1,100 to 3,000 of the population. Clinically, LQTS is characterized by syncope, cardiac arrest and occasionally, by a history of seizures. The QT interval can also be prolonged by drugs, electrolyte imbalances, toxins and certain medical conditions. Long QT syndrome patients are at risk of torsades de pointes and ventricular fibrillation. Medical management aims to reduce dysrhythmia frequency. The LQTS is subdivided into different groups (LQT1-6) depending on the cardiac ion channel abnormality. Torsades can be precipitated by adrenergic stimuli such as stress or pain (LQT1 and 2), sudden noises (LQT2) or whilst sleeping (LQT3). Patients with LQTS require careful anesthetic management as they are at high risk of torsades perioperatively despite minimal data on the effects of anesthetic agents on the QT interval. While information on effects of LQTS in pregnancy is limited, the incidence of dysrhythmia increases postpartum. Isolated case reports of patients with LQTS women highlight several peripartum dysrhythmias. CONCLUSION: An understanding of LQTS and the associated risk factors contributing to dysrhythmias is important for anesthesthesiologists caring for parturients with LQTS. 相似文献
69.
Sean J. Barnett M.S. M.D. Christopher Stanley B.S. Melanie Hanlon R.N. C.N.P. Robert Acton M.D. Daniel A. Saltzman M.D. Ph.D. Sayeed Ikramuddin M.D. Henry Buchwald M.D. Ph.D. 《Surgery for obesity and related diseases》2005,1(4):1609-398
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy. 相似文献
70.
Metabolic consequences of very-low-calorie diet therapy in obese non-insulin-dependent diabetic and nondiabetic subjects 总被引:1,自引:0,他引:1
To determine the effects of very-low-calorie diets on the metabolic abnormalities of diabetes and obesity, we have studied 10 obese, non-insulin-dependent diabetic (NIDDM) and 5 obese, nondiabetic subjects for 36 days on a metabolic ward during consumption of a liquid diet of 300 kcal/day with 30 g of protein. Rapid improvement occurred in the glycemic indices of the diabetic subjects, with mean (+/- SEM) fasting plasma glucose falling from 291 +/- 21 to 95 +/- 6 mg/dl (P less than 0.001) and total glycosylated hemoglobin from 13.1 +/- 0.7% to 8.8 +/- 0.3% (P less than 0.001) (normal reference range 5.5-8.5%). Lipid elevations were normalized with plasma triglycerides reduced to less than 100 mg/dl and total plasma cholesterol to less than 150 mg/dl in both groups. Hormonal and substrate responses were also comparable between groups with reductions in insulin and triiodothyronine and moderate elevations in blood and urinary ketoacid levels without a corresponding rise in free fatty acids. Electrolyte balance for sodium, potassium, calcium, and phosphorus was initially negative but approached equilibrium by completion of the study. Magnesium, in contrast, remained in positive balance in both groups throughout. Total nitrogen loss varied widely among all subjects, ranging from 70 to 367 g, and showed a strong positive correlation with initial lean body mass (N = 0.83, P less than 0.001) and total weight loss (N = 0.87, P less than 0.001). The nondiabetic group, which had a significantly greater initial body weight and lean body mass than the diabetic group, also had a significantly greater weight loss of 450 +/- 31 g/day compared with 308 +/- 19 g/day (P less than 0.01) in the diabetic subjects. The composition of the weight lost at completion was similar in both groups and ranged from 21.6% to 31.3% water, 3.9% to 7.8% protein, and 60.9% to 74.5% fat. The contribution of both water and protein progressively decreased and fat increased, resulting in unchanged caloric requirements during the diet. This study demonstrates that short-term treatment with a very-low-calorie diet in both obese diabetic and nondiabetic subjects results in: safe and effective weight loss associated with the normalization of elevated glucose and lipid levels, a large individual variability in total nitrogen loss determined principally by the initial lean body mass, and progressive increments in the contribution of fat to weight loss with stable caloric requirements and no evidence of a hypometabolic response. 相似文献