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A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses. 相似文献
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Stefan Ockert Hardy Schumacher Dittmar Böckler Katrin Malcherek Jochen Hansmann Jens Allenberg 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):725-730
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic
aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares
the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA).
Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared
to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm
results were obtained through clinical investigation and magnetic resonance angiography imaging.
Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall
in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group
and 29 patients from the AAA group (82.9%) were alive.
Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate
without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms. 相似文献
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Jochen P?ling Wolfgang Rees Vittorio Mantovani Stephan Klaus Ludger Bahlmann Virgilius Ziaukas Norbert Hübner Henning Warnecke 《European journal of cardio-thoracic surgery》2006,30(4):597-603
BACKGROUND: For the first time, microdialysis was used to investigate in vivo and online the myocardial metabolism during and after cardiac surgery in patients treated with two different methods of myocardial protection. METHODS: Thirty patients underwent standard CABG with one of two different methods of myocardial protection. The patients were randomised to receive either cold blood (COLD group) or warm modified Calafiore cardioplegia (WARM group). Microdialysis probes were implanted into the myocardium of left ventricular apical region of the heart. Cardioplegia was given antegrade only. Microdialysis measurements were performed at time intervals before, during and 24 h after cardiopulmonary bypass and analysed for glucose, lactate, pyruvate and glycerol. RESULTS: Myocardial lactate concentrations were significantly higher in the WARM group compared with that of the COLD group, while serum lactate was comparable. Glycerol was significantly higher at the end of the clamping time in the WARM group. At the same time the glucose-lactate ratio as a marker of nutritional disorder had significantly lower levels in the WARM group. The cumulative CK-MB release over 24 h was significantly higher in those hearts protected with warm blood. CONCLUSIONS: The oxidative stress measured was significantly higher in patients undergoing CABG using modified Calafiore cardioplegia, whereas the cold cardioplegia minimised the effects of aortic clamping. The results indicate that cold cardioplegia offers superior protection of the heart, in terms of more rapid normalisation of myocardial metabolism. In elective myocardial revascularisation, intermittent antegrade warm blood cardioplegia is a comparable safe method of myocardial protection. However, in patients referring to a long clamping time, advantages of cold cardioplegia for myocardial revascularisation may be magnified. 相似文献
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Jochen Woicke Stephen K. Durham Mark G. Mense 《Experimental and toxicologic pathology》2007,59(3-4):197-204
Nucleoside analogues are used in the treatment of viral infections, including those caused by human immunodeficiency virus, cytomegalovirus, and herpes virus. These drugs are beneficial in the treatment of human disease, but are associated with toxicities that often limit their intended therapeutic use, including anemia, neutropenia, peripheral neuropathy, and myopathy. Some of these compounds have been reported to be carcinogenic in rodents. To investigate the carcinogenic potential of lobucavir, a nucleoside analogue, three groups of 60 male and female mice were orally administered lobucavir at daily doses of 10, 50, and 250 mg/kg (males) or 30, 150, and 750 mg/kg (females) over a period of 104 weeks. Two identical groups of 60 male and female mice each served as controls. The morphology and the incidence of neoplasms is described and compared with the tumor spectrum of other nucleoside analogues. Light microscopically, lobucavir-induced neoplastic lesions consisted of upper digestive tract squamous cell neoplasia in males and females; cervical, vaginal, and cutaneous squamous cell neoplasia in females; and Hardarian gland adenomas and adenocarcinomas in male mice. These results suggest that long-term administration of lobucavir causes neoplasia in mice, the spectrum of which resembles that observed after long-term administration of zidovudine or ganciclovir. 相似文献
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Pape Lars; Mengel Michael; Offner Gisela; Ehrich Jochen H.H. 《Nephrology, dialysis, transplantation》2004,19(12):3207
Sir, A 4-year-old boy presented with oedema and weight gain of 5kg. There had been no preceding infections, vaccinations ormedication. The family history includes the mothers mesangioproliferativeglomerulonephritis. Laboratory results showed decreased albumin (13 g/l) concentration.Calculated glomerular filtration rate was 125 ml/min/1.73 m2and the 相似文献
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