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The effect of chemical shift on magnetic resonance (MR) imaging of the pituitary fossa was studied. Healthy volunteers underwent conventional MR imaging of the pituitary fossa and then imaging with the frequency-encoding gradient reversed or with the phase- and frequency-encoding gradients interchanged. Comparison of the image pairs in each subject showed that the thin, black stripe evident at the water-fat interface within the pituitary fossa was altered when the gradients were changed. Therefore, the low-intensity signal within the pituitary fossa is a chemical shift misregistration effect. 相似文献
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Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
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Maristella?D'Uva Ida?Strina Antonio?Mollo Antonio?Ranieri Giuseppe?De Placido Pierpaolo?Di MiccoEmail author 《Journal of translational medicine》2005,3(1):43
Background
Antiphospholipid syndrome (APS) has been often associated to RPL since 1980 and some reports in the Literature rarely described antibodies to factor XII in patients with APS. 相似文献9.
Paradiso A Ranieri G Silvestris N Naccarato G Bevilacqua G Mangia A Leone B Vallejo C Simone G Schittulli F De Lena M 《Clinical and experimental medicine》2001,1(3):127-132
In the present study, the primary tumor angiogenesis characteristics of 81 stage IV previously untreated breast cancers with
synchronous metastasis to different distant sites (10 patients with soft tissue metastases, 31 with bone metastases, and 40
with visceral metastases) were analyzed. The primary intratumor microvessel density was assessed by immunohistochemical assay
on paraffin-embedded primary tumor samples, using a monoclonal anti-CD34 antibody. The mean primary intratumor microvessel
density (at 400× fields) was 78±39 (SD) microvessels per field. The microvessel density was not significantly related to the
main clinical/pathological features of the tumor (age, cytohistological grade, DNA ploidy, diameter, and receptor status).
The percentage of tumor cases with high primary intratumor microvessel density (cut-off median value of the series 73±39 microvessels/field)
did not significantly differ in patients with bone, soft tissue, or visceral metastatic disease. Aanalysis of clinical outcome
showed a significantly shorter time to progression and overall survival for patients with visceral metastases (P<0.001 and P<0.0002 by log-rank, respectively). Presence of visceral metastases was confirmed to be the only independent prognostic factor
related to a worse TTP (hazard risk 2.15, 95% confidence interval 1.14–4.03, P<0.02) and overall survival (hazard risk 1.81, 95% confidence interval 0.98–3.35, P<0.06) by multivariate analysis. In conclusion, the assessment of neoangiogenesis of primary breast cancer by CD34 expression
does not provide information predictive of different distant sites of metastasis.
Received: 15 June 2001 / Accepted: 12 September 2001 相似文献
10.
E. M. Wilson A. J. Ranieri Jr. O. L. Updike J. F. Dammann Jr. 《Medical & biological engineering & computing》1972,10(2):179-191
The thermal dilution method offers a number of advantages in the measurement of cardiac output particularly when measurements at frequent intervals over prolonged periods are required. The sources of error in the quantification of thermal indicator input and other factors pertinent to the applicability of this method to serial measurements in an automated clinical environment are discussed. 相似文献