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Walter R T Witschey Arijitt Borthakur Mark A Elliott Eric Mellon Sampreet Niyogi Chenyang Wang Ravinder Reddy 《Magnetic resonance in medicine》2007,57(1):2-7
The origin of image artifacts in an off-resonance spin-locking experiment is shown to be imperfections in the excitation flip angle. A pulse sequence for off-resonance spin locking is implemented that compensates for imperfections in the excitation flip angle through an off-resonance rotary echo. The off-resonance rotary echo alternates the frequency offset and phase of the RF transmitter during two spin-locking pulses of equal duration. The underlying theory is detailed, and MR images demonstrate the effectiveness of the technique in agarose gel phantoms and in in vivo human brain at 3T. 相似文献
134.
Clemens Aigner Guenther Winkler Peter Jaksch Gernot Seebacher Gyorgy Lang Sharokh Taghavi Wilfried Wisser Walter Klepetko 《European journal of cardio-thoracic surgery》2005,27(5):757-761
OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage. 相似文献
135.
Shahrokh Taghavi Katharina Krenn Peter Jaksch Walter Klepetko Seyedhossein Aharinejad 《American journal of transplantation》2005,5(6):1548-1552
Bronchiolitis obliterans (BO) is a survival-limiting factor in lung transplantation. There are no common BO markers in use. Since BO is associated with extracellular matrix remodeling, we asked whether matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs) could serve as BO markers. In 72 lung transplant patients (34 BO syndrome (BOS) 0, 15 BOS 0-p, and 23 BOS 1) serum and broncho-alveolar lavage (BAL) MMP and TIMP levels were examined by ELISA. The BAL cell counts were additionally analyzed. The serum MMP-2, MMP-8, MMP-9 and TIMP-2 levels were not different in all groups. In contrast, the BAL MMP-8, -9 and TIMP-1 levels were significantly elevated in BOS 0-p (p = 0.003; p = 0.007; p = 0.0003, respectively) and BOS 1 (p = 0.003; p = 0.001; p = 0.0004, respectively) as compared to BOS 0 patients. The BAL MMP-8, -9 and TIMP-1 levels were significant predictors of BOS 0-p (p = 0.01; p = 0.01; p = 0.01, respectively) and BOS-1 (p = 0.007; p = 0.01; p = 0.006, respectively) in receiver operating characteristic analysis. Except for BAL macrophages that were significantly decreased in BOS 0-p versus BOS 0 patients; other cell counts were not different between the groups. BAL MMP-8, -9 and TIMP-1 might be useful markers to detect BO in lung transplant patients. 相似文献
136.
M Walter C G McDonald B W Paty A M J Shapiro E A Ryan P A Senior 《Diabetic medicine》2007,24(2):161-165
AIMS: Autoimmune diseases such as Addison's or coeliac disease can contribute to hypoglycaemia or malabsorption and are more common in Type 1 diabetes (T1DM). This brief report describes the prevalence of known and newly detected autoimmune disease in clinical islet transplant candidates with longstanding T1DM and severe hypoglycaemia and/or glycaemic lability who are routinely screened for coexisting autoimmune disease. METHODS: One hundred and twenty-four C-peptide negative T1DM subjects [77 (62%) female, mean age 44 +/- 9 years, diabetes duration 28 +/- 11 years, body mass index 24.9 +/- 3.5 kg/m(2)] with indications for clinical islet transplantation at the University of Alberta were screened for autoimmune disease by history and measurement of anti-transglutaminase antibodies (positive > 10 U/ml), 09.00 h cortisol (followed by adrenocorticotrophic hormone-stimulation if < 495 nmol/l) and thyroid-stimulating hormone to determine the prevalence of coeliac disease, Addison's disease and autoimmune thyroid disease, respectively. RESULTS: Forty per cent of subjects had one or more coexisting autoimmune disease. The prevalence of autoimmune disease was 35%, coeliac disease 8% and Addison's disease 1.6%. In 11 individuals (9%), one or more autoimmune disease were newly detected (seven coeliac disease and five thyroid disease). Seven of 10 cases of coeliac disease were newly detected. A gluten-free diet in individuals with newly diagnosed coeliac disease reduced gastrointestinal symptoms, but indications for clinical islet cell transplantation persisted. CONCLUSIONS: Coexisting autoimmune disease is common in candidates for clinical islet cell transplantation. Screening in this group identified a substantial number of previously unrecognized cases. Clinicians should consider the presence of autoimmune disease even in the absence of classical symptoms. 相似文献
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139.
Walter Zidek 《Medizinische Klinik》2005,4(1):347-352
Ein 57-jähriger Bankangestellter stellt sich wegen seit Monaten bestehender Abgeschlagenheit und Müdigkeit vor. Anamnese: seit 3 Jahren dokumentierte Hypercholesterinämie (Gesamtcholesterin 350 mg/dl) und Hypertriglyzeridämie (Triglyzeride 430 mg/dl), zurzeit mit einem Statin behandelt, ferner seit einem 1/2 Jahr symptomatische Gicht (letzter Anfall vor 4 Wochen), jetzt mit 300 mg Allopurinol behandelt, sowie Claudicatio intermittens (Gehstrecke 300 m) bekannt. Seit der Jugend ist zudem ein allergisches Asthma bekannt, das mit inhalativen Steroiden und einem lang wirkenden β-Mimetikum behandelt wird. Die Frage nach Dyspnoe, Thoraxschmerzen oder einer plötzlich auftretenden Hautblässe wird verneint.Körperliche Untersuchung: Gewicht 89,2 kg, Größe 1,78 m, Blutdruck 210/90 mmHg. Die 24-h-Blutdruckmessung zeigt eine nächtliche Blutdrucksenkung von 15% systolisch und 12% diastolisch. In der Routinelaboruntersuchung keine Auffälligkeiten, insbesondere ausgeglichene Elektrolyte, normale Nierenfunktion. Im Urin-Stix keine Erythrozyt- oder Proteinurie. Verlauf: Der Patient erhält zunächst 5 mg Amlodipin und wird bezüglich nichtmedikamentöser Maßnahmen eingehend beraten. Bei einer Wiedervorstellung nach 3 Wochen hat er 1,5 kg an Gewicht abgenommen und einen Blutdruck von 170/85 mmHg. 相似文献
140.
Wim Van Biesen Walter Boer Bart De Greve Clement Dequidt Denise Vijt Dirk Faict Norbert Lameire 《Peritoneal dialysis international》2004,24(3):222-230
BACKGROUND: Glucose is an accepted osmotic agent for peritoneal dialysis (PD) although it has several drawbacks. Some of these drawbacks have been addressed by the introduction of solutions with low glucose degradation products and physiological pH in dual-chambered bags. Despite this achievement, there is a need for alternative osmotic agents.This randomized clinical trial analyzes 3-month's clinical experience with a mixture of 0.6% amino acids and 1.4% glycerol. METHODS: The study was performed at the renal units of the University Hospitals Ghent, Belgium, and Utrecht, The Netherlands. Stable PD patients were randomized for either protocol A (test solution, n = 5) or protocol B (control regimen, n = 5). In both protocols, there was a run-in phase of 1 month with a dialysis regimen of 2 x 2 L 2.27% glucose solution (Dianeal; Baxter, Nivelles, Belgium), 1 x 2 L Extraneal (Baxter), and 1 x 2 L glucose solution (Dianeal). After this month-long run-in period, patients in group A received during 3 months 2 x 2 L amino acid/glycerol solution, 1 x 2 L Extraneal, and at least 1 x 2 L of a classic glucose solution. RESULTS: Glucose absorption decreased in the test group during the test phase (from 84.2 +/- 8.7 to 11.7 +/- 11.6 g/24 hours, p = 0.001). Dialysate levels of cancer antigen 125 (CA125) increased in the test group, from 17.5 +/- 11.0 to 32.4 +/- 4.6 units/L (p = 0.04), whereas, in the control group, the levels remained stable (15.5 +/- 8.7 and 14.9 +/- 9.8 units/L respectively, p = 0.4).There were no differences in serum urea, serum bicarbonate, serum osmolarity, serum albumin, or parameters related to skin-fold thickness or serum glycerol levels between control and test solutions. No differences were observed in obtained ultrafiltration after a 4-hour dwell with 2.27% glucose or the test solution, both measured at week 4 of the run-in period and week 12 of the test period. CONCLUSION: This study demonstrated that the use of a new 0.6% amino acid/1.4% glycerol-containing dialysis solution is safe and well tolerated. Glucose load was reduced significantly and dialysate CA125 levels improved significantly. Ultrafiltration was comparable with that of a 2.27% glucose solution. All these factors, in combination with the potential nutritional benefits, can contribute to a beneficial impact on the success of the PD technique. Further long-term studies in larger patient groups are warranted to explore the potential of this promising new solution. 相似文献