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81.
P Lahermo A Sajantila P Sistonen M Lukka P Aula L Peltonen ML Savontaus 《Canadian Metallurgical Quarterly》1996,58(6):1309-1322
The genetic relationships between two Finno-Ugric-speaking populations, the Finns and the Finnish Saami (Lapps), were studied by using PCR for six nuclear-DNA marker loci, mitochondrial restriction-site polymorphism, and sequence variation of a 360-bp segment of the mitochondrial control region. The allele frequencies of each of the nuclear-DNA marker loci and the frequencies of mtDNA restriction haplotypes were significantly different between the populations. The Saami showed exceptionally low variation in their mtDNA restriction sites. The 9-bp deletion common in East Asian populations was not observed, nor did the haplotype data fit into the haplogroup categorization of Torroni et al. The average number of nucleotide substitutions from the mtDNA haplotype data indicated that the Finnish Saami may be closer to the Finns than to the other reference populations, whereas nuclear DNA suggested that the Finns are more closely related to the European reference populations than to the Finnish Saami. The similarity of the Finns to the other Europeans was even more pronounced according to the sequence data. We were unable to distinguish between the Finns and either the Swiss or Sardinian reference populations, whereas the Finnish Saami clearly stood apart. The Finnish Saami are distinct from other Circumarctic populations, although two of the lineages found among the Saami showed closer relationship to the Circumarctic than to the European lineages. The sequence data indicated an exceptionally high divergence for the Saami mtDNA control lineages. The distribution of the pairwise nucleotide differences in the Saami suggested that this population has not experienced an expansion similar to what was indicated for the Finns and the reference populations. 相似文献
82.
R Mann EK Yeong ML Moore LH Engrav 《Canadian Metallurgical Quarterly》1997,18(2):160-3; discussion 159
This article introduces a new tool to measure the pressure that is under pressure garments. The Iscan (Tekscan, Inc.) system uses a patented ultra-thin (0.007 inch) sensor with multiple sensing locations that sample continuously at 100 times per second. It is noninvasive, convenient, and quick. The study had two parts. First, we established the validity and reliability of the device. Next, garment/scar interface pressures were measured on new garments with use of the Iscan system. Four garment types were studied, with 10 measurements made in each group: Isotoner gloves (Smith & Nephew Roylan, Inc.); custom-fit pressure gloves; Tubigrip forearm sleeves (Seton Health Care Group); and custom-fit pressure forearm sleeves. Mean garment/scar interface pressures were 18 +/- 2 mm Hg for the Isotoner glove, 34 +/- 5 mm Hg for the custom-fit pressure glove, 20 +/- 7 mm Hg for the Tubigrip sleeve, and 35 +/- 6 mm Hg for the custom-fit sleeve. We concluded that the Iscan system can be used to measure pressure under pressure garments accurately and reliably, and that custom-fit hand and forearm garments provide more pressure than Isotoner gloves or Tubigrip sleeves. 相似文献
83.
F Namouni F Doz ML Tanguy E Quintana J Michon H Pacquement E Bouffet JC Gentet D Plantaz P Lutz JP Vannier P Validire S Neuenschwander L Desjardins JM Zucker 《Canadian Metallurgical Quarterly》1997,33(14):2368-2375
This study investigates the role of high-dose chemotherapy with haematopoietic stem cell rescue as consolidation treatment in high-risk retinoblastoma (extraocular disease at diagnosis or relapse or invasion of cut end of optic nerve). 25 patients received high-dose chemotherapy including carboplatin (250 mg/m2/day from day 1 to day 5 for the 6 first patients and 350 mg/m2/day from day 1 to day 5 for the other patients), etoposide (350 mg/m2/day from day 1 to day 5) and cyclophosphamide (1.6 g/m2/day from day 2 to day 5) (CARBOPEC) followed by autologous haematopoietic stem cell rescue. 19 patients received this drug combination for chemosensitive extraocular relapse. The other 6 patients with histological high-risk factors were given this treatment as consolidation after enucleation and conventional chemotherapy. The three year disease-free survival was 67.1%. In 7 of the 9 relapsing patients, the first site of relapse was the central nervous system. All patients with central nervous system disease died except one. The main toxicity was haematological and digestive (mucositis and diarrhoea). 2 of the 13 evaluable patients had grade III and IV ototoxicity. One patient experienced an acute grade I reversible cardiotoxicity. The CARBOPEC regimen seems to be a promising therapeutic strategy in patients with high-risk retinoblastoma, especially those with bone and/or bone marrow involvement. This treatment did not improve the outcome of patients with central nervous system disease. 相似文献
84.
85.
Necrotizing fasciitis (NF) is a rapidly progressive soft tissue infection with high morbidity and mortality rates. Its occurrence in the head and neck region is uncommon, the majority of reported cases being limited to involvement of the neck, usually from infections of dental or pharyngeal origin. Involvement of the face from NF is rare; only 35 such cases have been reported in the literature since 1960. It is not only associated with a high mortality but can also result in severe disfigurement of the face, posing challenging reconstructive problems. Successful management of facial NF requires early diagnosis, prompt institution of broad spectrum antibiotics, aggressive surgical debridement to control the infection, and reconstruction of the resultant soft tissue defects. This report describes four additional cases of facial necrotizing fasciitis. One of the four patients died as a result of sepsis and multi-organ system failure. Two of the three surviving patients had significant facial disfigurement. A comprehensive review of the facial NF cases reported in the literature is also provided. Based on our experience with facial NF and the results of all previous case reports, the clinical manifestations, pathogenesis, and management of this disease are discussed. 相似文献
86.
The first stages of nickel electrodeposition on amorphous carbon and polycrystalline silver substrates have been studied under galvanostatic conditions. An island growth mode is observed on the two types of substrate. For equivalent conditions the cluster density is higher on silver substrates than on carbon substrates. Dissolution of some nickel clusters is observed a short time after the onset of electrolysis on carbon substrates. This is confirmed by the evolution of the current efficiency and the evolution of the metal surface cluster density as a function of the quantity of electricity. 相似文献
87.
Wrinkling is a well known phenomenon experimented by tension membranes in Civil Engineering applications. This paper will
present an efficient numerical technique for the computational simulation of such wrinkles in a prestressed membrane. In particular,
the relaxed energy approach (Pipkin in IMA J Appl Math 36:85–99, 1986) is particularized for prestressed membranes (Gil in
Textile composites and inflatable structures, CIMNE, 2003) undergoing moderate strains. Wrinkling conditions in terms of the
Euler-Lagrange finite deformation tensor along principal directions will be obtained. This will provide a framework to describe
properly the initial instant when wrinkles start to be encountered in a prestressed Saint Venant–Kirchhoff hyperelastic membrane.
Subsequently, a modified Helmholtz’s free energy functional will be introduced with the purpose of describing the modified
constitutive behaviour of the continuum after the onset of wrinkling. Consistent derivations of the stress tensor as well
as the constitutive tensor will de depicted. The results will be particularized for membranes and cables in a Finite Element
discretization basis. Some numerical examples will prove the accuracy and robustness of the described algorithm. 相似文献
88.
ML Cruz 《Canadian Metallurgical Quarterly》1995,87(1-2):26-28
The author provides an introduction to the risk management process in the hospital industry as well as explains some of the basic elements in a risk management program in such industry. The author also explains the factors to be evaluated in a risk management program. 相似文献
89.
J Buc CL Santini F Blasco R Giordani ML Cárdenas M Chippaux A Cornish-Bowden G Giordano 《Canadian Metallurgical Quarterly》1995,234(3):766-772
A soluble alpha beta complex of nitrate reductase can be obtained from a strain of Escherichia coli that lacks the narI gene and expresses only the alpha and beta subunits. The beta subunit contains four Fe-S centres and the alpha subunit contains the molybdenum cofactor, which is the site at which nitrate is reduced. Despite the lack of the gamma subunit of the complete enzyme, this complex can still catalyse the reduction of nitrate with artificial electron donors such as benzyl viologen, so that it is suitable for studying the transfer of electrons between these two types of redox centre. To examine whether the electrons from reduced benzyl viologen are initially delivered to the Fe-S centres, or directly to the molybdenum cofactor, or both, we have studied the steady-state kinetics and the binding of benzyl viologen to the alpha beta complex and mutants alpha beta* with altered beta subunits. Reduction of the enzyme by reduced benzyl viologen in the absence of nitrate showed that all four Fe-S centres and the molybdenum cofactor could be reduced. Two classes of site with different equilibrium constants could be distinguished. The kinetic results suggest that benzyl viologen supplies its electrons directly to the molybdenum cofactor, at a rate showing a hyperbolic dependence on the square of the concentration of the electron donor. A reaction mechanism is proposed for the reduction of nitrate catalysed by the alpha beta complex of nitrate reductase with artificial electron donors. 相似文献
90.