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21.
SM Davison SJ Skidmore KE Collingham WL Irving SG Hubscher DA Kelly 《Canadian Metallurgical Quarterly》1998,28(5):764-770
BACKGROUND/AIMS: Chronic graft hepatitis occurs in 20-30% adults after liver transplantation but the prevalence and causes in children are not known. In adults, hepatitis C virus infection is prevalent prior to transplantation and recurrent infection is a frequent cause of graft dysfunction. The significance of the recently described hepatitis G virus infection remains unproven. The aim of this study was to examine the role of hepatitis C virus and hepatitis G virus infection in chronic graft hepatitis after paediatric liver transplantation. METHODS: The prevalence of graft hepatitis and the role of hepatitis C virus and hepatitis G virus infections in 80 children after liver transplantation have been studied, with a median follow up of 4.4 years (range 0.4 to 10.7), and the persistence of hepatitis G infection in the presence of immunosuppression has been determined. RESULTS: Chronic graft hepatitis was diagnosed in 19/80 (24%) children and was most frequently seen in children transplanted for cryptogenic cirrhosis (71%). There was no significant difference in the prevalence of chronic hepatitis in those transplanted before or after donor anti-HCV screening. Hepatitis C infection occurred in three children transplanted prior to donor screening but in only one was associated with chronic hepatitis. Hepatitis G infection was found in 22/79 (28%) transplant recipients but was not associated with graft hepatitis. In 17/21 children hepatitis G infection persisted for a median of 5.2 years after transplantation. CONCLUSION: Chronic hepatitis occurred in 24% of children after liver transplantation, a similar prevalence to that in adults. Cryptogenic liver disease predisposed to graft hepatitis, but neither hepatitis C nor hepatitis G infection was associated. Hepatitis G virus caused a frequent and usually persistent infection after transplantation. 相似文献
22.
WL Olszewski 《Canadian Metallurgical Quarterly》1996,29(3):126-131
Dermatolymphangioadenitis (DLA) is a common and serious complication of obstructive peripheral lymphedema. The clinical characteristics of acute DLA are local tenderness and erythema of the skin, sometimes red streaks along the distribution of the superficial lymphatics and enlarged inguinal lymph nodes. Systemic symptoms include malaise, fever and chills. In its subacute or latent form, only skin involvement is observed. Each episode of DLA is commonly followed by worsening of leg swelling. Numerous clinical studies suggest that administration of antibiotic drugs interrupt the acute episodes and prevent their recurrence. We investigated the clinical course of lymphedema with respect to the prevalence of DLA in patients receiving injections of long-acting penicillin (benzathine penicillin). Forty-five randomly selected patients with obstructive lymphedema of the lower limbs were included in an open clinical trial. The inclusion criteria was stage II-IV lymphedema of postsurgical, posttraumatic, and postdermatitis type with at least 3 previous episodes of DLA. Benzathine penicillin (PCN) was given after the last presenting episode of DLA in a dose of 1,200,000 u, intramuscularly at 3-week intervals, for at least one year. Each patient was reevaluated at 3-month intervals. They were instructed in early diagnosis of DLA and reported promptly to the responsible senior surgeon with prodrome symptoms of recurrent DLA. The duration of lymphedema before initiation of therapy was 7 months to 40 years and the frequency of DLA was 1-6 episodes per year. PCN administration lasted for at least one year but was extended in all patients because of the tendency for recurrence of DLA after cessation of PCN injections. In 26 of these patients, PCN administration extended to over 5 years and in 2 over 10 years. Recurrent episodes of DLA occurred in the PCN-treated group during one year follow-up in only 4 of the 45 patients (9%). The frequency episodes in 3 patients with recurrent DLA was 1-2/year; in one patient, no positive effect of PCN therapy was observed. There were no apparent side effects of long-term PCN therapy. These data, although evaluated without a placebo group, suggest that long-term PCN administration decreases the frequency of DLA attacks and furthermore provide justification for carrying out a double-blind randomly placebo-controlled clinical trial of the efficacy of prophylactic antibiotic drug treatment in forestalling DLA episodes. 相似文献
23.
Patricia M. Cooney J. E. Hodge C. D. Evans 《Journal of the American Oil Chemists' Society》1958,35(4):167-171
Summary Amino reductones derived from hexoses were evaluated for color development in heated, oxidizing fat systems. Browning was
observed to some extent with all the amino-hexose-reductones. The brown color frequently faded upon long heating of the oils.
The density of color increased with reductone concentration and varied markedly among the different amino reductones. Morpholino-hexose-reductone
could be used in lard and vegetable oils at concentrations up to 0.01% without introducing visually detectable amounts of
color. Heating soybean oil solutions of the amino reductones at 100°C. under vacuum slowly destroyed the reductone but did
not cause development of color. Air or oxygen was required for color production. Addition of citric acid along with the reductone
reduced the amount of color developed. Reductones in fat systems show similarities in browning to reductones in aqueous systems.
New considerations for the mechanism of antioxidation by polyphenols and reductones in oils are presented.
Presented at the spring meeting, American Oil Chemists’ Society. New Orleans, La., April 28-May 1, 1957. 相似文献
24.
Victoria J. Hodge Rajesh Krishnan Jim Austin John Polak Tom Jackson 《Neural computing & applications》2014,25(7-8):1639-1655
This paper introduces a binary neural network-based prediction algorithm incorporating both spatial and temporal characteristics into the prediction process. The algorithm is used to predict short-term traffic flow by combining information from multiple traffic sensors (spatial lag) and time series prediction (temporal lag). It extends previously developed Advanced Uncertain Reasoning Architecture (AURA) k-nearest neighbour (k-NN) techniques. Our task was to produce a fast and accurate traffic flow predictor. The AURA k-NN predictor is comparable to other machine learning techniques with respect to recall accuracy but is able to train and predict rapidly. We incorporated consistency evaluations to determine whether the AURA k-NN has an ideal algorithmic configuration or an ideal data configuration or whether the settings needed to be varied for each data set. The results agree with previous research in that settings must be bespoke for each data set. This configuration process requires rapid and scalable learning to allow the predictor to be set-up for new data. The fast processing abilities of the AURA k-NN ensure this combinatorial optimisation will be computationally feasible for real-world applications. We intend to use the predictor to proactively manage traffic by predicting traffic volumes to anticipate traffic network problems. 相似文献
25.
Bithalamic hyperintensity on T2-weighted MR: vascular causes and evaluation with MR angiography 总被引:1,自引:0,他引:1
PURPOSE: To determine whether MR angiography can be used to differentiate between the two vascular causes of bithalamic hyperintensity on T2-weighted MR images: "top of the basilar" artery occlusion and deep cerebral vein thrombosis. METHODS: A retrospective review identified six patients with bithalamic T2 hyperintensity of vascular causes. MR angiography was performed in four patients, MR angiography and conventional angiography in one patient, and conventional angiography in one patient. Data pertaining to clinical presentation and hospital course were collected. MR angiographic techniques were multislab overlapping three-dimensional time-of-flight, 2-D time-of-flight, and 2-D phase-contrast. RESULTS: Three cases of top of the basilar artery occlusion and three cases of deep cerebral vein thrombosis were recognized. In all cases, T2 hyperintensity in a vascular distribution suggested cerebral occlusive disease. Infarction involving the thalami and basal ganglia was present in two cases of deep cerebral vein thrombosis. Infarction of the thalami, mesodiencephalic region, and cerebellar hemispheres was present in two cases of basilar artery occlusion. Bithalamic infarction alone was seen in one case of deep cerebral vein thrombosis and one case of basilar artery occlusion. In the five cases in which MR angiography was used, this technique accurately distinguished the vessels involved (arterial or venous). CONCLUSION: MR angiography is a useful adjunct to MR imaging in the evaluation of bithalamic T2 hyperintensity. It does help distinguish between the two vascular causes: top of basilar artery occlusion and deep cerebral vein thrombosis. 相似文献
26.
27.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy. 相似文献
28.
WL George BD Kirby VL Sutter DM Citron SM Finegold 《Canadian Metallurgical Quarterly》1981,3(3):599-626
Twenty infrequently reported species of gram-negative anaerobic bacilli other than Fusobacterium nucleatum, Fusobacterium necrophorum, and members of the genus Bacteroides were studied with regard to their role in infection and their susceptibility to antimicrobial agents. In addition, the literature regarding the recovery of these organisms from both the normal flora and infections of humans was reviewed. During a six-year period at the Wadsworth Clinical Anaerobic Bacteriology Research Laboratory (Veterans Administration Wadsworth Medical Center, Los Angeles, Calif.), 39 (6%) of 679 specimens obtained from anaerobic infections yielded "other gram-negative anaerobic bacilli" (OGNAB). Fusobacterium naviforme, Fusobacterium gonidiaformans, Fusobacterium varium, Fusobacterium mortiferum, and Fusobacterium russii were the most commonly isolated OGNAB. Most of the OGNAB tested were resistant to erythromycin, and most strains, except for F. varium, were susceptible to beta-lactam antibiotics and clindamycin. Chloramphenicol and metronidazole were active against all strains of OGNAB tested. Certain Fusobacterium species are undoubtedly previously unrecognized members of the normal flora of the oropharynx, upper respiratory tract, or urogenital tract and may be present in infections derived from these floras. 相似文献
29.
The surface microstructure and polymorphic behavior of milk chocolate subjected to multiple thermal cycles between 20 and
32, 33, or 34°C were examined using atomic force microscopy (AFM) and powder X-ray diffraction (XRD). The surface of unbloomed
milk chocolate was smooth (surface roughness of 278 nm) and consisted of small, evenly distributed crystals. XRD results indicated
the presence of mostly form V crystals and little or no form VI crystals. Cycling between 20 and 32°C resulted in little bloom
formation and change in polymorphic behavior. Gradual bloom formation occurred as a result of cycling between 20 and 33°C,
and was accompanied by the nascence of form VI crystals. Surface roughness increased gradually from 417 nm after one cycle
to 476 and 521 nm after two and three cycles, respectively. Extensive bloom arose from cycling between 20 and 34°C. Surface
roughness increased from 373 nm after one cycle to 603 and 736 nm after two and three cycles, respectively. This heavily bloomed
chocolate consisted of jutting crystals and large raised, yet smooth areas that were haphazardly located within the chocolate
matrix. In summary, a new perspective on the development of surface bloom due to thermal cycling is provided. 相似文献
30.
Gerald Hodge 《Journal of the American Planning Association. American Planning Association》2013,79(2):112-121
By developing measurement scales the city planner can promote his long-run interest in integrating urban knowledge and his short-run interest in making valid analyses of specific problems. But the construction of measurement scales is not a random process and must be conducted according to logical rules. Inadequacies in current city planning scales are largely attributable to the lack of adherence to these rules. Housing quality scales, the most common measurement device in city planning, reveal some of the difficulties that lead to deficiencies in our measurement. The outlook is far from gloomy. Experience from other fields in index number construction, the use of scalograms, and factor analysis can Open up many promising avenues for city planning measurement. 相似文献