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1.
2.
Steven R. Jensen M.D. Dawn R. Voegeli John C. McDermott Andrew B. Crummy 《Cardiovascular and interventional radiology》1986,9(4):202-204
Eight lymphatic fluid collections were drained percutaneously. There were no immediate or late complications. Seven patients
had follow-up; 1 required surgical drainage of a residual or recurrent lymphocele, and another had reaccumulated fluid in
a lymphocele which was detected on autopsy. The remaining lymphatic collections responded to percutaneous drainage. Percutaneous
drainage is safe and can be an effective tool in the management of lymphatic collections. 相似文献
3.
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
4.
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
5.
F T McDermott G Whelan D J St John G L Barnes R Elliott R Herrmann G T Schmidt R A Smallwood 《The Medical journal of Australia》1987,146(10):525, 528-525, 529
Information on the relative incidence of Crohn's disease and ulcerative colitis was obtained by a prospective investigation at six Melbourne teaching hospitals. One hundred and eleven patients who presented with chronic inflammatory bowel diseases between 1980-1981 were admitted to the study. Forty (36%) patients were diagnosed as having Crohn's disease and 63 (57%) patients as having ulcerative colitis. The type of chronic inflammatory bowel disease could not be determined in eight (7%) patients. These findings suggest that the relative frequency of Crohn's disease and ulcerative colitis in Melbourne hospitals is within the range that is reported for northern Europe and the United States. 相似文献
6.
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
7.
M.B. McDermott A.C. Lind E.F. Marley L.P. Dehner 《Pediatric and developmental pathology》1998,1(4):300-308
Deep granuloma annulare (DGA) is one of several lesions of skin and superficial soft tissues whose histologic character is
a palisading granuloma with a small central focus of necrosis or necrobiosis. Unlike the other palisading necrobiotic lesions,
DGA has a predilection for children in the first 5 to 6 years of life. A painless subcutaneous nodule(s) in the lower anterior
tibial region or foot and the scalp, typically in the occiput, was the most common presenting feature in this study of 35
cases. Additional or recurrent lesions were reported in approximately 70% of cases with clinical follow-up. All lesions showed
the presence of necrobiosis; however, one of the characteristic features was the multinodular character of the predominantly
mononuclear cellular aggregates. The presence of vascular spaces at the periphery of the nodular profiles served as a clue
to the diagnosis of DGA. The palisading arrangement of the mononuclear cells was evident only in those foci with central necrobiosis.
A histiocytic disorder or fibrohistiocytic process was a common consideration in the differential diagnosis, especially in
those cases with less apparent foci of necrosis. Palisading histiocytes with prominent eosinophilic cytoplasm and some nuclear
atypism were problematic with regard to possible epithelioid sarcoma. Our study failed to identify any underlying or predisposing
factors in the development of DGA. Despite the fact that DGA is a well-documented lesion in children, it occurs sufficiently
infrequently that it is often not considered clinically when it presents as a subcutaneous mass or masses in a child. Its
recognition by the pathologist is especially important as the occurrence of additional lesions in a high proportion of children
can be anticipated without undue concern.
Received June 16, 1997; accepted October 28, 1997. 相似文献
8.
J. O’Byrne S. Eustace M. M. Stephens M. N. M. R. Farahat G. Yanni R. Posten G. S. Panayi S. Sant R. Costello M. Barry J. Hassan C. Feighery B. Bresnihan A. Whelan F. Coakley A. M. de Paor R. B. Reilly E. B. Casey V. J. Tormey G. Kearns K. Gaffney P. J. Freyne M. Callaghan O. FitzGerald D. Veale E. O’Nuallain D. Reen D. Veale M. Farrell O. FitzGerald S. Rogers L. Barnes R. J. Coughlan C. McCarthy M. McDermott D. Hourihane C. O'Morain S. O'Reilly P. Hartley E. Casey L. Clancy F. Mulcahy N. Hall A. Murphy C. Breen D. Kelleher M. Abuzakouk C. O'Farrelly 《Irish journal of medical science》1992,161(6):438-442
9.
Robert J. McDermott PhD CHE FASHA Wesley E. Hawkins PhD Phillip J. Marty PhD CHES Eliza Ames Littlefield PhD Susan Murray RN Thomas K. Williams EdD 《The Journal of school health》1990,60(8):414-417
Frequency of symptoms of depression and selected health-related practices and events were measured in a sample of 219 high school students. Students reported numerous symptoms of depression. Relative proportions of boys and girls reporting symptoms of depression were not significantly different. However, girls reported experiencing more severe depression than their male counterparts. Depression correlated significantly with several of the 22 health practices and states of affect examined. Both the determinants and manifestations of depression in adolescent cohorts require in-depth investigation. Possible implications for school health personnel are discussed. 相似文献
10.
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