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1.
2.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
3.
Shigeru Ichioka MD ; Naomi Sekiya MT ; Masahiro Shibata PhD ; Takashi Nakatsuka MD 《Wound repair and regeneration》2007,15(4):572-576
The leukocyte-endothelium interaction is known to contribute to reperfusion injury, which is considered to participate in the pathophysiology of pressure ulcers, and integrin alphaV beta3 (alphavbeta3) has been shown to mediate the processes of cellular adhesion in various types of cells. This study aims to clarify leukocyte behavior in our original microcirculatory pressure-induced reperfusion model, which can visualize the microcirculation in vivo. We also estimated the effect of alphavbeta3 integrin inhibition on the reduction of the leukocyte-endothelium interaction. Mice with dorsal skinfold chambers were divided into three groups: the baseline group (n=6), in which animals received no compression; the compression-reperfusion group (n=6), in which animals underwent 2-hour compression of the dorsal skin, followed by release, and the inhibitor-treated group (n=7), in which an alphavbeta3 inhibitor, CP4715, was administered in addition to the compression-release procedure. Staining with rhodamine 6G quantitatively visualized leukocyte behavior under the intravital fluorescent microscope. Compression-reperfusion induced a significant increase in rolling, sticking, and extravasation of the leukocytes. Treatment with the inhibitor strikingly reduced leukocyte sticking and extravasation. The present experiment has provided evidence that alphavbeta3 inhibition reduces leukocyte-endothelium interaction in our original pressure-induced reperfusion model. 相似文献
4.
Dr. S. Eggstein MD G. Manthey MT T. Hirsch PhD F. Baas MA B. U. V. Specht MD E. H. Farthmann MD 《Digestive diseases and sciences》1996,41(6):1069-1075
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr). 相似文献
5.
6.
Symptoms versus flow rates versus urodynamics in the selection of patients for prostatectomy 总被引:1,自引:0,他引:1
Many prostatectomies are performed on the basis of symptoms alone; 39% of patients referred by their family doctors and 23% of patients who were on waiting lists for prostatectomy of other hospitals, but who had not undergone any urodynamic investigations, were found to be unobstructed on urodynamic criteria. A screening peak urinary flow rate of 12 ml/s or less was associated with urodynamic evidence of obstruction in 95% of cases; 35% of patients with symptoms of outflow obstruction and a flow rate greater than 12 ml/s were also found to be obstructed. One year post-operatively, 84% of patients who were selected for surgery on combined symptomatic and urodynamic criteria were pleased symptomatically with their result. The failure of detrusor instability to resolve following prostatectomy was associated with symptomatic failure of treatment. Residual obstruction was demonstrated in 5 patients who had undergone prostatectomy and were asymptomatic at this time. This study illustrates that objective measures are necessary in the assessment of patients prior to prostatectomy in order to select only patients who are obstructed. The importance of a screening flow rate is emphasised. All patients who underwent surgery had cystometric evidence of obstruction but the symptomatic results of surgery were no better than the results in patients who had been assessed according to non-urodynamic selection criteria. We have thus failed to identify a need for routine cystometry in the pre-operative assessment of these patients. Cystometry does, however, have a role in assessing patients with pre-operative flow rates greater than 12 ml/s and in those who remain symptomatic following prostatectomy. 相似文献
7.
S J McLoughlin S J Shaw S Turner B S Sylvester 《The Journal of hand surgery, European volume》1990,15(1):129-130
A case is described in which a deep palmo-planar wart (myrmecia) caused erosion of the underlying phalanx. 相似文献
8.
Analysis of ischemia-reperfusion injury in a microcirculatory model of pressure ulcers 总被引:2,自引:0,他引:2
Shinsaku Tsuji MD ; Shigeru Ichioka MD ; Naomi Sekiya MT ; Takashi Nakatsuka MD 《Wound repair and regeneration》2005,13(2):209-215
The aim of this study was to establish a pressure ulcer model that visualizes the microcirculation, and to examine the participation of ischemia-reperfusion injury in the pathophysiology of pressure ulcers. An original system composed of a new skin fold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia-reperfusion injury, animals were divided into two groups: the compression-release group (n = 8), in which the animals received four cycles of compression-release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group (n = 8) in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day 1 (35 hours) after the first evaluation. The cyclic compression-release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia-reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. This finding supports the significant contribution of ischemia-reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
9.
Midazolam sedation for outpatient fibreoptic endoscopy: evaluation of alfentanil supplementation. 总被引:1,自引:0,他引:1
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K. R. Milligan J. P. Howe J. McLoughlin W. Holmes J. W. Dundee 《Annals of the Royal College of Surgeons of England》1988,70(5):304-306
Alfentanil, a short-acting opioid, was used as an adjuvant to midazolam for sedation of 30 outpatients undergoing upper gastrointestinal endoscopy. The operating conditions and recovery times were compared with those of a similar group of 30 patients sedated with midazolam only. The use of alfentanil resulted in improved operating conditions and a more rapid recovery. Patient acceptance was high. 相似文献
10.
Denis O'Mullane PhD ; Helen P. Whelton PhD ; Pat Costelloe BDS David Clarke BDS ; Stephen McDermott MSc ; Jacinta McLoughlin MDS 《Journal of public health dentistry》1996,56(5):259-264
The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher. 相似文献