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71.
P Combemale J Kanitakis FX Maquart M D'Incan L Thomas 《Canadian Metallurgical Quarterly》1994,121(12):893-897
BACKGROUND: Pachydermoperiostosis (PDP) is a rare genetically determined disease belonging to the group of hypertrophic osteoarthropathies. Its aetiopathogenesis remains unclear. Most hypotheses favour an exogenous stimulation of fibroblasts. METHODS: A clinically typical patient with PDP was studied by electron microscopy with particular reference to the dermis and its cellular constituents. Fibroblasts from involved skin were cultured and studied in comparison with control cells. RESULTS: Remarkable modifications of the structure of the dermis were observed, encompassing irregular caliber of collagen fibres, extracellular deposits of microfibrils and of amorphous granular substance corresponding to the Alcian blue positive deposits seen by conventional histochemistry. The in vitro growth of fibroblasts was normal. CONCLUSION: Authors reviewed aetiopathogenic hypotheses. Our data suggest a genetically determined alteration of extracellular matrix production by fibroblasts as a possible explanation for the development of PDP. 相似文献
72.
73.
R Rull JC García-Valdecasas A Rimola L Grande J Beltrán J Tabet AM Lacy J Fuster P Taurá FX González W Jiménez J Visa 《Canadian Metallurgical Quarterly》1996,88(12):840-846
The aim of this study is to investigate the role of prostaglandins (PGI2 and TXA2) in relation with the hemodynamic alterations occuring after graft reperfusion in patients undergoing OLT. A total of 40 patients with liver cirrhosis were studied. Systemic 6-keto-PGF1 alpha and TXB2, stable metabolites of PGI2 and TXA2 respectively, were determined at the radial artery, at four different surgical stages: basal, hepatectomy, anhepatic, and 10 minutes after graft reperfusion. Overall results showed that 6-keto-PGF1 alpha levels were significantly elevated during hepatectomy (1143 +/- 204) when compared to values in the basal stage (p = 0.007). During hepatectomy, 6-keto-PGF1 alpha levels did not correlate to systemic vascular resistance index (SVRI), neither with the cardiac index (IC) nor with the medial arterial pressure (MAP) in the same stage. During the anhepatic stage, only IRVS was inversely correlated with 6-keto-PGF1 alpha levels (p = 0.004): there was no relation with MAP and CI. During reperfusion no correlations were observed between 6-keto-PGF1 alpha levels and MAP, CI or SVRI. We conclude that systemic PGI2 levels are very high in cirrhotic patients undergoing OLT. The absence of correlation between the magnitude of changes in hemodynamic parameters and 6-keto-PGF1 alpha levels during reperfusion of the new liver suggests that other factors must play a role in these hemodynamic changes. 相似文献
74.
B Fernhall KH Pitetti MD Vukovich N Stubbs T Hensen JP Winnick FX Short 《Canadian Metallurgical Quarterly》1998,102(6):602-612
The validity of the 600-yard walk/run, the 20-m shuttle run, and a modified 16-m shuttle run was determined to measure aerobic capacity (VO2peak) in children with mild and moderate mental retardation. Practice sessions for all tests were conducted. All field tests were very reliable, and VO2peak was significantly related to them all. A stepwise multiple regression showed that field test performance, body mass index (BMI), and gender, but not age, were also significant predictors of VO2peak. All field tests were valid and reliable indicators of aerobic capacity, suggesting that these tests can be used to predict VO2max in children with mild and moderate mental retardation. 相似文献
75.
LJ Ball-Goodrich SE Leland EA Johnson FX Paturzo RO Jacoby 《Canadian Metallurgical Quarterly》1998,72(4):3289-3299
A newly recognized parvovirus of laboratory rats, designated rat parvovirus type 1a (RPV-1a), was found to be antigenically distinct. It was cloned, sequenced, and compared with the University of Massachusetts strain of rat virus (RV-UMass) and other autonomous parvoviruses. RPV-1a VP1 identity with these viruses never exceeded 69%, thus explaining its antigenic divergence. In addition, RPV-1a had reduced amino acid identity in NS coding regions (82%), reflecting phylogenetic divergence from other rodent parvoviruses. RPV-1a infection in rats had a predilection for endothelium and lymphoid tissues as previously reported for RV. Infectious RPV-1a was isolated 3 weeks after inoculation of infant rats, suggesting that it, like RV, may result in persistent infection. In contrast to RV, RPV-1a was enterotropic, a characteristic previously associated with parvovirus infections of mice rather than rats. RPV-1a also differed from RV in that infection was nonpathogenic for infant rats under conditions where RV infection causes high morbidity and mortality. Thus, RPV-1a is the prototype virus of an antigenically, genetically, and biologically distinct rodent parvovirus serogroup. 相似文献
76.
The development of a workload management system for use in the accident and emergency department is described. The system is capable of capturing the work all professional groups, allowing the user to roster staff according to anticipated workload, and gives accurate information on whether staffing requirements are sufficient to provide the desired standard of care. 相似文献
77.
78.
CW Mandl H Holzmann T Meixner S Rauscher PF Stadler SL Allison FX Heinz 《Canadian Metallurgical Quarterly》1998,72(3):2132-2140
The flavivirus genome is a positive-strand RNA molecule containing a single long open reading frame flanked by noncoding regions (NCR) that mediate crucial processes of the viral life cycle. The 3' NCR of tick-borne encephalitis (TBE) virus can be divided into a variable region that is highly heterogeneous in length among strains of TBE virus and in certain cases includes an internal poly(A) tract and a 3'-terminal conserved core element that is believed to fold as a whole into a well-defined secondary structure. We have now investigated the genetic stability of the TBE virus 3' NCR and its influence on viral growth properties and virulence. We observed spontaneous deletions in the variable region during growth of TBE virus in cell culture and in mice. These deletions varied in size and location but always included the internal poly(A) element of the TBE virus 3' NCR and never extended into the conserved 3'-terminal core element. Subsequently, we constructed specific deletion mutants by using infectious cDNA clones with the entire variable region and increasing segments of the core element removed. A virus mutant lacking the entire variable region was indistinguishable from wild-type virus with respect to cell culture growth properties and virulence in the mouse model. In contrast, even small extensions of the deletion into the core element led to significant biological effects. Deletions extending to nucleotides 10826, 10847, and 10870 caused distinct attenuation in mice without measurable reduction of cell culture growth properties, which, however, were significantly restricted when the deletion was extended to nucleotide 10919. An even larger deletion (to nucleotide 10994) abolished viral viability. In spite of their high degree of attenuation, these mutants efficiently induced protective immune responses even at low inoculation doses. Thus, 3'-NCR deletions represent a useful technique for achieving stable attenuation of flaviviruses that can be included in the rational design of novel flavivirus live vaccines. 相似文献
79.
J Mostin P Mathurin P Goffette F Hammer RJ Opsomer F Lorge A Abi Aad P Van Cangh FX Wese 《Canadian Metallurgical Quarterly》1994,62(3):31-36
The varicocele is benign pathology which sometimes involves disorders of testicular growth. Those can cause a hypofertility. We saw in a retrospective way the 243 patients having been treated by percutaneous embolisation from May 1985 to August 1993. At 150 patients being 1 year at least of postoperative retreat, 70% of cases present a cure, 15% of patients repeated and were taken again surgically. At 8% of patients, the embolisation was not technically possible for reasons of vascular anomalies or spasm of the vein during the procedure. The morbidity of this technique is low, this involves therefore a right choice of the treatment of the varicocele which does not prevent any surgical treatment in the event of repetition or in the event of technical failure. 相似文献
80.
FX Arinto Setyawan Joo Kooi Tan Hyoungseop Kim Seiji Ishikawa 《Artificial Life and Robotics》2014,19(3):291-298
This paper proposes a method of detecting moving objects using sequential inference of the background in a video taken with a moving camera. In the video taken using a moving camera, all positions of pixels change every frame. The positions of the background pixels in the image frame T are not the same as the positions of the background pixels in the image frame T + 1. 2D projective transform can be used to find changes in the pixel position every frame. Bilinear interpolation with four nearest pixels around the pixel in image frame T which corresponds to a pixel in the image frame T+1 can be used for creating a background model at T + 1. Having obtained the background model, a pixel in image frame T + 1 can be determined if it is a background pixel or a foreground pixel. The detection results of the proposed method are compared with the ground truth to determine the effectiveness of the proposed method. 相似文献