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21.
P Flanagan KI McAnally RL Martin JW Meehan SR Oldfield 《Canadian Metallurgical Quarterly》1998,40(3):461-468
BACKGROUND: Atopic dermatitis (AD) is characterized by skin infiltrates of leukocytes, such as lymphocytes and eosinophils. OBJECTIVE: To describe the mechanisms determining this inflammatory process, we have analyzed expression of adhesion molecules and their regulation on skin endothelial cells (ECs). METHODS: Expression of adhesion molecules on ECs was analyzed by immunohistochemistry by using Ulex europaeus agglutin 1 as a pan-endothelial marker. RESULTS: Vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and P-selectin were not found in skin of nonatopic individuals, whereas expression of these surface molecules was observed in nonlesional skin of patients with AD and was even more pronounced in lesional skin or after epicutaneous application of aeroallergen. Induction of adhesion molecule expression was examined on both macrovascular ECs from human umbilical cord vein (HUVECs) and human microvascular ECs (HMEC-1) from skin. TNF-alpha very potently upregulated adhesion molecule expression in vitro on both EC cell types. To verify the in vivo relevance of TNF-alpha, we performed TNF-alpha staining in the skin. TNF-alpha was observed in the dermis of nonatopic skin, both in chymase-containing mast cells and CD68+ macrophages. The increase in the number of TNF-alpha-containing cells was concomitant with the increase in adhesion molecule expression in the skin of patients with AD. IL-4 is supposed to be important in atopic diseases because of its IgE- and VCAM-1-inducing properties. However, IL-4 addition failed to induce VCAM-1 expression on HMEC-1, although in the same set of experiments, a clear induction of VCAM-1 expression by IL-4 on HUVECs was demonstrated. Flow cytometry revealed the absence of 11-4 receptor alpha-chains on HMEC-1 and their presence on HUVECs. Immunohistochemistry examination on skin sections showed no binding of the IL-4R alpha-chain antibodies to ECs. CONCLUSION: We conclude that adhesion molecule expression is increased in the skin of patients with AD. Most probably, this increased expression is not a (direct) effect of IL-4 on skin endothelium, but other cytokines, such as TNF-alpha, might be responsible for this increased adhesion molecule expression. Continuous adhesion molecule expression may facilitate T-cell extravasation in a nonantigen-specific manner, thus explaining the presence of increased T-cell numbers in nonlesional skin of patients with AD. 相似文献
22.
STUDY OBJECTIVES: To assess the short- and long-term effects of balloon dilatation using a fiberoptic bronchoscope in the management of benign tracheobronchial stenosis (TBS). Treatment strategies have included open surgical resection or endoscopic techniques. The endoscopic techniques have included Nd:Yag laser, cryotherapy, stent placement, rigid bronchoscopy, and balloon dilation (BD). DESIGN: Prospective sequentiality study. SETTING: Tertiary care academic hospital. PATIENTS: This study consisted of 14 patients, ages ranging from 35 to 72 years, whose symptoms of dyspnea, cough, or wheeze were attributable to a TBS. INTERVENTION: This study describes the use of flexible fiberoptic bronchoscopy (FFB) with a balloon catheter for airway dilation. Each patient underwent FFB, in which a balloon catheter was threaded over the guidewire and positioned across the stenosis. Under direct visualization, the balloon was inflated for 30 to 120 s. Repeat inflation-deflation cycles were done if airway narrowing remained after the initial attempt. RESULTS: Seven patients had TBS following lung transplantation, three after sleeve resection, two following irradiation therapy, and two due to fibrosing mediastinitis. All patients had initial success: increased airway dimensions and symptom relief. Ten patients had successful airway dilation after one session. Of the four patients who required multiple sessions, one had cryotherapy and in each of the others an airway stent was placed. CONCLUSIONS: BD offers immediate symptom relief and can be used in conjunction with Nd:Yag laser, cryotherapy, stent placement, or mechanical dilation with a rigid bronchoscope. The advantages of FFB with BD include operator familiarity, patient safety, and avoidance of general anesthesia. 相似文献
23.
N Flanagan SA Boyadjiev J Harper L Kyne M Earley R Watson EW Jabs MT Geraghty 《Canadian Metallurgical Quarterly》1998,35(9):763-766
We report on the occurrence of coronal craniosynostosis, anal anomalies, and porokeratosis in two male sibs. A third male sib was phenotypically normal as were the parents. The occurrence of these three clinical features has, to our knowledge, not been reported before. Cutaneous or anal anomalies or both have been reported in a number of syndromes associated with craniosynostosis, including Crouzon, Pfeiffer, Apert, and Beare-Stevenson syndromes. These syndromes are associated with mutations in the fibroblast growth factor receptor genes FGFR1, FGFR2, and FGFR3. They are inherited in an autosomal dominant fashion. In contrast, the cases we report do not carry any of the common FGFR mutations and the pedigree suggests autosomal or X linked recessive inheritance. 相似文献
24.
JH Flanagan CV Owens SE Romero E Waddell SH Kahn RP Hammer SA Soper 《Canadian Metallurgical Quarterly》1998,70(13):2676-2684
A series of near-IR fluorescent dyes were prepared which contained an intramolecular heavy atom for altering the fluorescence lifetimes to produce a set of probes appropriate for base-calling in a single-lane DNA sequencing format. The heavy-atom modification consisted of an intramolecular halogen situated on a remote section of the chromophore in order to minimize the perturbation on the lifetimes and fluorescence quantum yields. In addition, the dye series possessed an isothiocyanate functional group to allow facile attachment to sequencing primers. The unconjugated dyes showed similar absorption and emission maxima (lambda abs = 765-768 nm; lambda em = 794-798 nm) as well as fluorescence quantum yields that were invariant, within experimental error, with the heavy atom. However, the lifetimes of these dyes were found to vary with the identity of the halogen substitution (I, tau f = 947 ps; F, tau f = 843 ps, measured in methanol), with an average variation within the dye series of 35 ps. The spectroscopic properties of the free dyes and the dyes conjugated to sequencing primers on the 5'-end of the oligonucleotide were determined in a DNA-sequencing matrix (denaturing gels containing formamide). The results indicated slight differences in the fluorescence properties of the free dyes compared to those of the dye/ primer conjugates in this particular matrix. Inspection of the ground-state absorption spectra showed significant aggregation for the free dyes in this solution, but the conjugated dyes exhibited no sign of aggregation due to the highly anionic nature of the oligonucleotide. The fluorescence lifetimes of the dye/primer conjugates demonstrated lifetimes which ranged from 735 to 889 ps, with an average variation of 51 ps, an adequate difference to allow facile discrimination of these dyes in DNA-sequencing conditions. In addition, the free solution electrophoretic mobilities of the native heavy-atom-modified dyes were found to be very similar. When the dye/primer conjugates were electrophoresed in a cross-linked polyacrylamide gel electrophoresis capillary column, they comigrated, indicating that, in single-lane sequencing applications, when utilizing these dyes, no postrun corrections would be required to correct for dye-dependent mobility shifts. 相似文献
25.
DA Flanagan SB Gladding FR Lovell 《Canadian Metallurgical Quarterly》1998,64(7):670-2; discussion 673
99Tc-sestamibi prone scintimammography (SMM) is a new, noninvasive method of imaging breast tumors. A pilot study has suggested that SMM increases the specificity of mammography, and that SMM could be used as an adjunct to mammography to reduce the number of mammographically indicated biopsies. The goal of this study was to further evaluate the efficacy of SMM in diagnosing or excluding breast carcinoma. This was a prospective case series with each patient serving as her own control. All subjects who had an abnormal mammogram, a palpable breast mass, or both were eligible for inclusion. All patients underwent breast examination, conventional mammography, SMM, and breast biopsy. Of the 81 women originally enrolled, 79 women with 80 lesions completed the study. SMM produced the following results: a sensitivity of 81 per cent, a specificity of 81 per cent, a positive predictive value of 61 per cent, and a negative predictive value of 92 per cent. These values were significantly lower than the pilot study results at a power of 80 per cent and P = 0.05. Our results indicate that SMM does not increase the specificity of conventional mammography and has a low negative predictive value. We would not recommend it as a screening technique to avoid biopsy. 相似文献
26.
Thirty-two neonates (26 term and 6 premature) having seizures were prospectively recruited and studied. Using prolonged video/EEG monitoring, we quantified seizure variables (electrographic and clinical seizure durations, interictal periods and electrographic seizure spread) for all 1,420 seizures recorded. The effects of time and antiepileptic drug (AED) therapy were analyzed statistically. Seizures were generally frequent, with limited electrographic spread. However, some neonates had consistently longer interictal periods and 13% had mean interictal periods > 60 min. Seizure variables were relatively stable over time, but they changed with AED therapy. There was a trend to decreased seizure duration, increased length of interictal periods, and decreased electrographic spread. Furthermore, there was evidence of reduced clinical features after sequential AED infusions. Seizures ceased during the monitoring period in 22 neonates. Eighty-five percent of all seizures had no clinical manifestations. Among neonates with clear clinical correlates, clinical observations underestimated electrographic seizures in individual neonates by a mean of 54% (range 0-95%). Seizures generally had limited electrographic spread. Use of only four recording electrodes, characteristic of some portable EEG systems, underestimated seizures in 19 neonates, and missed all seizures in 2. 相似文献
27.
Flanagan Constance A.; Cumsille Patricio; Gill Sukhdeep; Gallay Leslie S. 《Canadian Metallurgical Quarterly》2007,99(2):421
The developmental correlates of diffuse support for the polity and civic commitments were explored in a survey of 1,052 students (mean age = 14.96 years) from African American, Arab American, European American, and Latino American backgrounds. Results of structural equation modeling revealed that regardless of their age, gender, or ethnic background, youth were more likely to believe that America was a just society and to commit to democratic goals if they felt a sense of community connectedness, especially if they felt that their teachers practiced a democratic ethic at school. Discussion focuses on the civic purposes of education in inculcating a sense of identification with the polity in younger generations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Thirty-four adults with severe traumatic brain injuries (TBI) and 34 matched control participants were asked to interpret videotaped conversational exchanges. Study participants were asked to judge the speakers' emotions, the speakers' beliefs (first-order theory of mind), what the speakers intended their conversational partners to believe (second-order theory of mind), and what they meant by remarks that were sincere or literally untrue (i.e., a lie or sarcastic retort). The TBI group had marked difficulty judging most facets of social information. They could recognize speaker beliefs only when this information was explicitly provided. In general, emotion recognition and first-order theory of mind judgments were not related to the ability to understand social (conversational) inference, whereas second-order theory of mind judgments were related to that ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
A Flanagan 《Canadian Metallurgical Quarterly》1997,19(6):1540-1544
In recent years, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) has expanded its traditional role as a leading evaluator of health care organizations to incorporate new attitudes and strategies in the areas of quality and performance improvement. This paper outlines plans for modifying the current accreditation process, and includes a proposition that accredited organizations actively participate in a quality measurement system and become involved in the process of selecting appropriate measures. The paper presents current and proposed methods for measuring performance standards, compares major accreditation systems, and explores the public's expectations for health care quality and the JCAHO's role in quality improvement and cost containment. 相似文献
30.
D.J. Campbell V.H. Guthrie G.R. Burdick J.C. Glynn G.F. Flanagan 《Nuclear Engineering and Design》1985,89(2-3)
This paper outlines a four-step approach, that, if followed, will make the results of completed probabilistic risk assessments (PRAs) valuable for prioritizing the NRC's inspection resources so that they have their maximum risk-reduction effect. The paper also describes current work to apply the procedure. The product of the current work will be a computer program that displays important PRA results using decision-oriented, user-friendly personal computer software. 相似文献