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51.
A Herment E Mousseaux A De Cesare O Jolivet P Dumée A Todd-Pokropek J Bittoun 《Journal of magnetic resonance imaging : JMRI》1999,10(5):851-860
A technique dedicated to spatial regularization of magnetic resonance (MR) velocity data has been implemented to improve flow image quality. It is assumed that neighboring flow-velocity pixels are partially correlated, although large-velocity discontinuities remain possible. Increasing MR signal magnitude due to the in-flow effect also is used to enhance further reliability of the estimated velocity. By using an eight-step Fourier-encoding approach, 162 "reference" velocity images acquired in the ascending aorta from six healthy volunteers were compared with "raw" and "regularized" images that were computed from only two gradient steps. The mean square error decreased from 0.12 m(2) x s(-2) to 0.06 m(2) x s(-2) (P < 10-9) for velocity pixel values and from 1929 ml(2) x s(-2) to 1336 ml(2) x s(-2) (P < 0.01) for instantaneous flow rates. The regularization of two-step data sets provides the same velocity image quality as that found after using three-step data sets without regularization. The method can be applied to phase-velocity data sets of any MR technique to reduce velocity noise. J. Magn. Reson. Imaging 1999;10:851-860. 相似文献
52.
Polito C La Manna A Mansi L Rambaldi PF Papale MR Marte A Di Toro R 《Pediatric nephrology (Berlin, Germany)》1999,13(9):876-879
Body growth was studied in 32 subjects with vesicoureteric reflux (VUR), diagnosed following the prenatal finding of urinary
tract dilatation, who had normal renal filtration function and who received antibacterial prophylaxis by the first few days
of life. They were followed for 1–5 years (mean 2.3 years). Most had persistent VUR during the 1st year of life. Body growth
performance was compared with that of 94 subjects with VUR diagnosed and treated by us after the neonatal period. During the
follow-up period, none of the patients with prenatally detected VUR had a height Z score below –2, nor a weight-for-height
index below 90%, and 1 had variations in height Z score ≥1. The difference in the percentage of patients with prenatally detected
VUR (1/32) and those with VUR diagnosed and treated after the neonatal period (20/94) who had variations in height Z score
≥1 was significant (P=0.035). Patients with prenatally detected VUR and normal renal filtration function, given antibacterial prophylaxis by the
first few days of life, have normal body growth, although VUR still persists.
Received: 19 March 1998 / Revised: 10 February 1999 / Accepted: 10 February 1999 相似文献
53.
Fascicular tachycardia sensitive to calcium antagonists 总被引:3,自引:0,他引:3
Five patients with recurrent tachycardias exhibiting right bundlebranch block with left axis deviation were referred for investigation.In each case, a supraventricular mechanism was suspected. Duringsinus rhythm, the QRS morphology and axis (10 to +60degrees) and HV intervals were normal. Tachycardia was initiatedby timed ventricular premature stimuli in 4 patients, rapidventricular pacing in 3 patients and rapid atrial pacing in2 patients. The tachycardia cycle length varied from 275 to380 ms with right bundle branch block and a leftward axis changeof 30 to 125 degrees at the onset of the tachycardia. The HVinterval ranged from +15 to 20 ms. In each patient ventriculoatrialdissociation occurred spontaneously or could be induced. Alltachycardias could be terminated or greatly slowed by calciumantagonists. These data are consistent with an unusual reentrantmechanism of tachycardia located in the posterior fascicle ofthe left bundle branch. 相似文献
54.
In our Institute we have performed 124 vertical banded gastroplasties. Patients with a follow-up beyond 3 months were studied
with a barium meal, in order to evaluate the efficiency of surgery and the eventual complications. Seventy-nine patients have
had one or more X-ray investigations at various times after surgery (for a total of 136 studies). The first 20 patients were
routinely studied at 1, 2 and 3 years after the operation; the next 32 patients were studied for features such as vomiting,
poor weight loss or low food intake; the last 27 patients were studied with an early overlook beginning 3 months after surgery.
We noted gastroesophageal reflux in eight (10.1%) cases, outlet dilatation in four (5%) cases, outlet substenosis (diameter
6-8 mm) in 13 (16.4%) cases, outlet stenosis (diameter ≤5 mm) in four (5%) cases, peanut-type deformation in three (3.7%)
cases, and staple-line disruption in 17 (21.5%) cases. The staple-line disruption was correlated in the first part of the
series with a reinforcement of such a suture, while the last 27 patients, with vertical stapling carried out with a 4-row
stapler without reinforcement, did not present any disruption. The radiographic examination gives information about weight
loss and side effects. 相似文献
55.
J F Sneddon D E Ward I A Simpson N J Linker R J Wainwright A J Camm 《British heart journal》1991,65(3):143-147
Transcoronary ablation of atrioventricular conduction by dehydrated alcohol was attempted in 14 patients with refractory atrial arrhythmias. Alcohol (0.5 or 1.0 ml) was delivered after selective catheterisation of the atrioventricular nodal artery in the 10 patients in whom the artery could be identified by cineangiography. The other four patients underwent electrical ablation when the nodal artery could not be catheterised. Temporary atrioventricular block induced by dilute contrast and cold saline (0.9%) confirmed that the catheter was in the correct position before the alcohol was delivered. In all 10 patients complete atrioventricular block developed after alcohol ablation. The block persisted in all four patients given 1.0 ml alcohol but not in four of the six given 0.5 ml. The mean (SD) creatine kinase (MB fraction) at four to six hours after ablation was 76.5 (49.5) IU after 1.0 ml and 75.5 (43.1) IU after 0.5 ml alcohol (normal less than 20 IU). The overall success rate of alcohol ablation in the whole group on an "intention to treat" basis was 43%. The procedure was a technical success in six of the 10 patients in whom the nodal artery was identified. Transcoronary alcohol ablation of atrioventricular conduction should be considered in patients in whom electrical techniques have been unsuccessful. 相似文献
56.
57.
Tiziano Maggino M.D. Cesare Romagnolo M.D. Fabio Landoni M.D. Enrico Sartori M.D. Paolo Zola M.D. Angiolo Gadducci M.D. 《Gynecologic oncology》1998,68(3):274-279
Objective.The aim of this study was to define the clinical–therapeutical approach to endometrial cancer now being followed in some of the most important centers of reference for gynecological cancer in North America by means of a questionnaire.Study design.The questionnaire focused on four principal areas: (1) surgical staging and therapy; (2) adjuvant treatment; (3) treatment modifications; and (4) management of advanced stages (FIGO III–IV).Results.There were 48 evaluable responses (77%) received by the end of December 1994 which were considered for this analysis. Lymphadenectomy is utilized routinely in 26/48 centers (54.2%) and in selective clinical–pathological conditions in another 21/48 centers (43.5%). In the majority of centers (31/48; 64.6%) radical surgery is utilized for selected indications such as cervical involvement. Only 3/48 (6.2%) centers consider the vaginal approach totally inappropriate. The great majority (40/48; 83.3%) of the centers considered postsurgical adjuvant therapy to be necessary in FIGO Stage Ic. Brachytherapy is routinely performed in 3 centers (6.2%) in postsurgical management of Stage I endometrial cancer, while the majority of the centers (31/48; 64.6%) perform brachytherapy of the vaginal vault in certain clinical–pathological conditions. A wide variety of treatments are used for advanced stages (FIGO III–IV).Conclusions.It emerges that some controversial aspects exist on endometrial cancer treatment, and these conflicting data need a large-scale multicenter randomized clinical trial. 相似文献
58.
59.
Fabio Scopesi Silvana Canini Cesare Arioni Massimo Mazzella Diego Gazzolo Pasquale B Lantieri Wanda Bonacci Giovanni Serra 《The journal of maternal-fetal & neonatal medicine》2006,19(6):343-346
BACKGROUND: Recently we demonstrated an increased 2,3-diphosphoglycerate (2,3-DPG) erythrocyte concentration in rat pups subjected to nucleotide-enriched artificial feeding. DESIGN: The present study was carried out to test the hypothesis that a possible increase in 2,3-DPG concentration can also be obtained in human neonates who are fed nucleotide-enriched formula. Preterm neonates born or referred to the neonatal intensive care unit of the G. Gaslini Hospital, Genoa University, with a gestational age >30 weeks and <37 weeks were enrolled in our randomized trial. Recruitment took place within 48-72 hours from birth. Only newborns of mothers deciding not to breast-feed were eligible to be randomized for the supplemented group (FN) or non-supplemented group (RF). Breast-fed newborns were considered the control group (C). The study window (for supplementation and blood samples) was restricted to the first two weeks following birth (from the 2nd (t1) to the 16th (t2) day of life). At the end of our study, only 21 neonates were eligible for statistical analysis. RESULTS: The stimulating action of dietary nucleotides on 2,3-DPG concentration failed to be demonstrated; increases in 2,3-DPG concentration that were observed in newborns fed with nucleotide supplemented formula (FN) were comparable to those observed in newborns fed with regular formula (RF) and breast-fed newborns. CONCLUSIONS: The EC recommendation for the amount of nucleotides allowed in formula milk does not seem to be high enough to have positive effects on 2,3-DPG synthesis. Whether this possible 'pharmacological' effect can be achieved by a higher intake of ingested nucleotides and/or a change in the proportions of single nucleotides contained in milk formulas remain interesting end points to be elucidated. 相似文献
60.
Antonio Leone Marzia Marino Claudia Dell’Atti Viola Zecchi Nicola Magarelli Cesare Colosimo 《Rheumatology international》2016,36(10):1335-1346
The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine. 相似文献