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81.
Parpal J.-L. Awad R. Choquette M. Becker J. Hiivala L. Chatterjee S. Kojima T. Rosevear R.D. Morelli O. 《Power Delivery, IEEE Transactions on》1997,12(2):547-550
Extruded polymeric cables and accessories are an alternative to self-contained fluid filled (SCFF) cables for extra-high-voltage (EHV) systems. Crosslinked polyethylene (XLPE) insulated cables have many advantages over the traditional fluid-filled pressurized cable system with the elimination of the hydraulic system and the associated equipment and complications during the installation and operation/maintenance of such systems. Other advantages of the extruded cable system arise from the new accessory technologies and the use of splices and terminations that are prefabricated and pretested in the factory and require less time to install on site. Concerns over the long term reliability of high voltage cable systems, in particular the accessories and the lack of service experience above 300 kV led to the decision of Hydro-Quebec to carry out a prequalification (long-term) test program to assess the reliability of the cable materials and to verify the cable and accessory installation methods to be employed. The cables were installed in duct banks and manholes simulating actual installation conditions used in Hydro-Quebec underground cable network. This paper describes the program and results of the prequalification tests of 345-kV XLPE cables and accessories performed at Hydro-Quebec's Research Institute (IREQ) in partnership with three international cable manufacturers, Alcatel, Fujikura and Pirelli 相似文献
82.
Mauro A. La-Scalea Carla M.S. Menezes Guilherme C. Matsutami Sílvia H.P. Serrano 《Electrochimica acta》2006,51(24):5103-5111
The 8-aminoquinoline primaquine (PQ) is the only antimalarial drug used as tissue schizonticide and relapsing malaria. Antichagasic activity was also reported. Nevertheless, as it also shows serious side effects, prodrugs such as succinyl and maleyl derivatives have been proposed to decrease its toxicity. Although PQ mechanism of action has not been completely elucidated, the promotion of oxidative stress is an advanced hypothesis that could explain its activity in both plasmodia and trypanosome parasites. The oxidation of PQ and its prodrugs, maleylprimaquine (MPQ) and succinylprimaquine (SPQ), was studied by cyclic voltammetry using glassy carbon electrode. All compounds were oxidized in aqueous medium, with the charge transfer process being pH-dependent in acidic medium and pH-independent in a weak basic medium, being the neutral form more easily oxidized. This indicated that the protonation of the nitrogen atoms displays a determinant role in the voltammetric oxidation, being both prodrugs more easily oxidized than PQ protonated forms, in the order: SPQ < MPQ < PQ. For a better understanding of this behavior, a molecular modeling study was performed using the AM1 semi-empirical method from Spartan 04 for Linux (v.119, Wavefunction Inc.). The medium pH showed to be fundamental not only to the electronic density of the quinoline ring but also to the rearrangement of the nitrogen side chain. The electronic density of primaquine non-protonated quinoline ring is higher than that in its protonated and diprotonated species. Also, the use of prodrugs and the degree of saturation of the carriers (maleic or succinic acid) interfere with this feature. SPQ and MPQ have a slight increase in the quinoline electronic density in comparison to PQ. Nevertheless, the carrier in the side chain of SPQ is closer to the quinoline ring than it is in MPQ, which accounts for the higher electronic density in the former. The most significant effect occurs in the correspondent protonated forms of the nitrogen quinoline. The application of molecular modeling study associated to voltammetric techniques showed to be an important way to understand the redox mechanism of electroactive drugs. These results may be related to a biological activity and can be useful to future primaquine derivatives design. 相似文献
83.
T Gayowski N Singh IR Marino H Vargas M Wagener C Wannstedt F Morelli T Laskus JJ Fung J Rakela TE Starzl 《Canadian Metallurgical Quarterly》1997,64(3):422-426
BACKGROUND: End-stage liver disease due to hepatitis C virus (HCV) is the most common indication for liver transplantation in U.S. veterans. We investigated the influence of HCV genotypes on the incidence and timing of recurrent HCV hepatitis, survival, infectious morbidity, and response to interferon-alpha therapy in this unique patient population. METHODS: HCV genotype was determined by direct sequencing of the NS5 region of HCV with type-specific primers. RESULTS: Genotype 1a (66%, 32/47) was the predominant genotype. Type 1b was found in 25% (12/47) of patients and type 2b was found in 9% (4/47). Histopathologically recurrent HCV hepatitis developed in 53% (25/47) of the patients after transplantation. This group included 45% (14/31) of the patients with type 1a, 67% (8/12) of the patients with type 1b, and 25% (1/4) of the patients with type 2b (P>0.5). The time to recurrence and the severity of HCV recurrence as defined by aminotransferase levels or Knodell scores were not different among the three genotypes. There was a trend toward a higher incidence of major infections in patients with type 1b (75%) versus type 1a (48%) and type 2b (50%) (P=0.11). The response to interferon-a therapy did not differ significantly among the genotypes. Mortality at 5 years was 16% (5/31) in patients with genotype 1a, 42% (5/12) in patients with genotype 1b, and 50% (2/4) in patients with genotype 2b (P=0.06). CONCLUSIONS: The incidence, time to recurrence, and response to interferon-alpha therapy did not differ between the various genotypes in our liver transplant recipients. However, there was a trend toward higher infectious morbidity and overall mortality in patients with genotype 1b after transplantation. 相似文献
84.
G Lelli A Tartarone C D'Addetta M D'Aloia G Di Maggio F Morelli 《Canadian Metallurgical Quarterly》1998,149(921):21-24
PURPOSE: To verify tolerance and clinical efficacy of high-dose chemotherapy (HDCT) in metastatic breast cancer (MBC). PATIENTS AND METHODS: We submitted to HDCT with autologous peripheral blood cells transplant 66 patients, with MBC responding to induction chemotherapy. The condizioning regimen was ICE: iphosphamide 3.3 g/m2 dd. -8/-6, carboplatin 450 mg/m2 plus etoposide 400 mg/m2 dd. -5/-3 (21 patients = 78%); CTM: cyclophosphamide 100 mg/kg dd. -4/-3, tyothepa 500 mg:m2 d.-5, mytoxantrone 40 mg/m2 d. -6 (6 patients, 22%). RESULTS: Median number of aphereses was 2 (range 1-5), median amount of CD34+ cells/kg bw of 10 x 10E6 (range 3.5-38.2). Median recovery time was 10th day for PMN (range 8-37) while for platelets it was 9th day (range 8-37): total hospital stay was of 24 days (range 22-48). After induction therapy we had PR in 13/27 metastatic patients (48%) and CR in 14/27 (52%). After conditioning treatment we had PR in 12/27 (44%) and CR in 15/27 (56%). Median time to progression was 19 months (range 7-38) and median survival 52 months (range 7-59+), with 30% surviving beyond 4 years. CONCLUSIONS: Feasibility of HDCT in advanced breast cancer seems verified. The promising results need to be confirmed. 相似文献
85.
Rothbaum Fred; Weisz John; Pott Martha; Miyake Kazuo; Morelli Gilda 《Canadian Metallurgical Quarterly》2001,56(10):827
Replies to comments by 7 authors (see records 2001-18772-008, 2001-18772-009, 2001-18772-010, 2001-18772-011, and 2001-18772-012) in reference to the F. Rothbaum et al's original article (see record 2000-02781-001), which highlighted evidence of cultural variations in, and noted ways in which attachment theory is laden with Western values and meaning in comparisons of the US and Japan. Here, Rothbaum et al defend their central thesis and note areas of their agreement and disagreement with the aforementioned comments and criticisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
87.
F Paolieri M Battifora AM Riccio G Ciprandi A Scordamaglia C Morelli M Bagnasco GW Canonica 《Canadian Metallurgical Quarterly》1997,52(9):935-943
Inhaled corticosteroids in the treatment of asthma have been shown to produce marked reductions in the number of inflammatory cells (mainly mast cells and eosinophils) and their products at bronchial level (such as cytokines). Recently, it has been demonstrated that epithelial cells express ICAM-1/CD54 in allergic patients both during natural allergen exposure and after allergen challenge. We have previously demonstrated that deflazacort (a systemic steroid) reduces the expression of ICAM-1 on conjunctival epithelial cells. The present study aimed to evaluate the effects exerted by budesonide on adhesion molecule expression by a human epithelial cell line (lung carcinoma: DM) and on soluble ICAM-1. Budesonide was added at concentrations corresponding to 10(-8), 10(-7), and 10(-6) mol/l in cultured epithelial cells, either in the absence of any stimulus or in the presence of interferon-gamma (IFN-gamma) at 500 U/ml. After 24 h of incubation, cytofluorometric analysis was performed for ICAM-1 and CD29/VLA beta 1. The 24-h supernatants of the same cultures were collected and then evaluated for soluble ICAM-1 (sICAM-1). The results showed that budesonide inhibits ICAM-1 and CD29 basal expression on the cells studied (P < 0.05): budesonide was effective in a dose-dependent manner. In addition, budesonide reduced surface ICAM-1 upregulation induced by IFN-gamma at 500 U/ml (P < 0.05). Finally, cell cultures with budesonide showed decreased levels of soluble ICAM-1 in basal condition, but not after IFN-gamma stimulation. 相似文献
88.
S Salminen A von Wright L Morelli P Marteau D Brassart WM de Vos R Fondén M Saxelin K Collins G Mogensen SE Birkeland T Mattila-Sandholm 《Canadian Metallurgical Quarterly》1998,44(1-2):93-106
Probiotics are commonly defined as viable microorganisms (bacteria or yeasts) that exhibit a beneficial effect on the health of the host when they are ingested. They are used in foods, especially in fermented dairy products, but also in pharmaceutical preparations. The development of new probiotic strains aims at more active beneficial organisms. In the case of novel microorganisms and modified organisms the question of their safety and the risk to benefit ratio have to be assessed. Lactic acid bacteria (LAB) in foods have a long history of safe use. Members of the genera Lactococcus and Lactobacillus are most commonly given generally-recognised-as-safe (GRAS) status whilst members of the genera Streptococcus and Enterococcus and some other genera of LAB contain some opportunistic pathogens. Lactic acid bacteria are intrinsically resistant to many antibiotics. In many cases resistances are not, however, transmissible, and the species are also sensitive to many clinically used antibiotics even in the case of a lactic acid bacteria- associated opportunistic infection. Therefore no particular safety concern is associated with intrinsic type of resistance. Plasmid-associated antibiotic resistance, which occasionally occurs, is another matter because of the possibility of the resistance spreading to other, more harmful species and genera. The transmissible enterococcal resistance against glycopeptide antibiotics (vancomycin and teicoplanin) is particularly noteworthy, as vancomycin is one of the last effective antibiotics left in the treatment of certain multidrug-resistant pathogens. New species and more specific strains of probiotic bacteria are constantly identified. Prior to incorporating new strains into products their efficacy should be carefully assessed, and a case by case evaluation as to whether they share the safety status of traditional food-grade organisms should be made. The current documentation of adverse effects in the literature is reviewed. Future recommendations for the safety of already existing and new probiotics will be given. 相似文献
89.
90.
Anil Mital Paul T. Kemmerling Robert D. Dryden Tom B. Leamon Donald L. Morelli Bahador Ghahramani 《IIE Transactions》1993,25(3):99-104
There is a growing concern in die labor sector to reduce stresses in the work place and the associated strains and adverse effects on health which result from newer forms of tasks that workers are increasingly called upon to perform. One approach to reducing stresses is to reduce the work-week (fewer hours per week). Social expectation of longer vacations and leisure time, demographic changes, and changes in the nature of die work and attitudes towards work also support this trend. The objective of this position paper is to consider the implication of such a move and the feasibility of this approach. Specifically, we consider the effects of a shorter work-week on productivity and economy and discuss the various patterns of shorter work-week. Finally, we present our position on die pattern of the shorter work-week in the United States in the future. 相似文献