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991.
Stable BHK-21 cell lines were constructed expressing the Golgi membrane-bound form and two secretory forms of the human alpha1, 3/4-fucosyltransferase (amino acids 35-361 and 46-361). It was found that 40% of the enzyme activity synthesized by cells transfected with the Golgi form of the fucosyltransferase was constitutively secreted into the medium. The corresponding enzyme detected by Western blot had an apparent molecular mass similar to those of the truncated secretory forms. The secretory variant (amino acids 46-361) was purified by a single affinity-chromatography step on GDP-Fractogel resin with a 20% final recovery. The purified enzyme had a unique NH2 terminus and contained N-linked endo H sensitive carbohydrate chains at its two glycosylation sites. The fucosyltransferase transferred fucose to the O-4 position of GlcNAc in small oligosaccharides, glycolipids, glycopeptides, and glycoproteins containing the type I Galbeta1-3GlcNAc motif. The acceptor oligosaccharide in bovine asialofetuin was identified as the Man-3 branched triantennary isomer with one Galbeta1-3GlcNAc. The type II motif Galbeta1-4GlcNAc in bi-, tri-, or tetraantennary neutral or alpha2-3/alpha2-6 sialylated oligosaccharides with or without N-acetyllactosamine repeats and in native glycoproteins were not modified. The soluble forms of fucosyltransferase III secreted by stably transfected cells may be used for in vitro synthesis of the Lewisa determinant on carbohydrates and glycoproteins, whereas Lewisx and sialyl-Lewisx structures cannot be synthesized. 相似文献
992.
993.
J Rodríguez I Muniategui M Bárcena J Costa J Alvarez 《Canadian Metallurgical Quarterly》1998,45(6):251-254
A two-years-old boy with Down's Syndrome and a small interauricular communication was given priority scheduling for adenoidectomy and tonsillectomy to correct subacute obstruction of the upper airway. The only noteworthy event during surgery was an SpO2 of 92% during mechanical ventilation with FiO2 of 0.5 from no apparent cause. The patient suffered acute respiratory insufficiency due to the post-obstructive pulmonary edema in the hours immediately following surgery. The incidence of post-obstructive pulmonary edema is higher than might be expected, as symptoms can be interpreted as aspiration pneumonitis or left ventricular failure. Given the high prevalence of adenoiditis and tonsillitis with varying degrees of airway obstruction in children, we consider it useful to report this case. Such patients should be monitored carefully in the early postoperative period. 相似文献
994.
Ant nio V. M. de Andrade Nivan B. da Costa Jr Oscar L. Malta Ricardo L. Longo Alfredo M. Simas Gilberto F. de S 《Journal of Alloys and Compounds》1997,250(1-2):412-416
A new theoretical methodology developed to guide the design of light-conversion molecular devices is applied to the complex tris(3-aminopyrazine-2-carboxylate)(1,10-phenanthroline) of Eu(III), and the results are compared to the experimental data obtained in our laboratory. The calculations have shown that there are two triplet states at 363 and 377 nm localized on the 1,10-phenanthroline, which are quasi-resonant with the 5G6 (374 nm) and 5L6 (395 nm) energy levels of the Eu(III) ion, respectively. The 3-aminopyrazine-2-carboxylate anion ligands have a richer quasi-resonant energy level structure, namely, three singlet states (344, 323 and 377 nm) and their corresponding triplet states (498, 509 and 530 nm), which are near-resonant to the 5D4 and 5D0 Eu(III) energy levels, respectively. These ligand and metal ion energy levels were used in the dipole–dipole and dipole-2ℓ-pole models for energy transfer rate calculations. Thus, the high quantum yield observed for this complex (28% in DMSO solution) seems to be due to the calculated high yield energy transfer from these several ligand states to the quasi-resonant Eu(III) energy levels. 相似文献
995.
In vitro bioassays were performed in order to assess the pathogenicity of 13 Penicillium strains in 2nd stage larvae of Aedes aegypti, Aedes fluviatilis, Anopheles aquasalis and Culex quinquefasciatus. Mortality rates began in the first 24 hours, ranging from 0 to 100%. P. corylophilum, P. fellutanum, P. implicatum, P. janthinellum, P. viridicatum and P. waksmanii species tested on Aedes aegypti larvae and at different concentrations presented mortality rates from 0 to 6.6%. These species, when tested on Aedes fluviatilis, Anopheles aquasalis and Culex quinquefasciatus larvae, presented a mortality rate of 3.33% to 100%. Susceptibility of Aedes fluviatilis, Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus mosquitoes to the tested agents, turn P. corylophilum and P. janthinellum into candidates for potential use in biological control of vectors. 相似文献
996.
A Da Costa G Kirkorian M Cucherat F Delahaye P Chevalier A Cerisier K Isaaz P Touboul 《Canadian Metallurgical Quarterly》1998,97(18):1796-1801
BACKGROUND: Infection remains a serious complication after permanent pacemaker implantation. Antibiotic prophylaxis is frequently prescribed at the time of insertion to reduce its incidence, although results of well-designed, controlled studies are lacking. METHODS AND RESULTS: We performed a meta-analysis of all available randomized trials to evaluate the effectiveness of antibiotic prophylaxis to reduce infection rates after permanent pacemaker implantation. Reports of trials were identified through a Medline, Embase, Current Contents, and an extensive bibliography search. Trials that met the following criteria were included: (1) prospective, randomized, controlled, open or blind trials; (2) patients assigned to a systemic antibiotic group or a control group; (3) end point events related to any infection after pacemaker implantation: wound infection, septicemia, pocket abscess, purulent secretion, right infective endocarditis, inflammatory signs, a positive culture, septic pulmonary embolism, or repeat operation for an infective complication. Seven trials met the inclusion criteria. They included 2023 patients with established permanent pacemaker implantation (new implants or replacements). The incidence of end point events in control groups ranged from 0% to 12%. The meta-analysis suggested a consistent protective effect of antibiotic pretreatment (P=.0046; common odds ratio: 0.256, 95% confidence interval: 0.10 to 0.656). CONCLUSIONS: Results of the present meta-analysis suggest that systemic antibiotic prophylaxis significantly reduces the incidence of potentially serious infective complications after permanent pacemaker implantation. They support the use of prophylactic antibiotics at the time of pacemaker insertion to prevent short-term pocket infection, skin erosion or septicemia. 相似文献
997.
Several algorithms for adaptive control, as well as for static state feedback decoupling, feedback linearization, or inversion of nonlinear multivariable systems require that the systems have full vector relative degree, in order to be applied. In this paper, we provide a parameter-independent method of achieving full vector relative degree for nonlinear multivariable systems which do not have it. We determine conditions under which a diagonal dynamic precompensation is sufficient to achieve vector relative degree for multivariable nonlinear systems, and describe a simple algorithm which determines such compensation. 相似文献
998.
JM Caralps i Riera J Montiel Serrano X Ruyra Baliarda H Litvan Suquieri F Carreras Costa 《Canadian Metallurgical Quarterly》1996,49(8):621-622
The performance of peroperative transesophageal echocardiography on a 60 year old woman with mitral and tricuspid valve disease discovered a previously undiagnosed thrombus in the right pulmonary artery that completely occluded the inferior lobar branches. Following valvular surgery, a successful thromboendarterectomy was performed. 相似文献
999.
ABSTRACTThe La Plata River Basin’s transboundary institutional arrangement is a complex system with different geographical bases and scopes, including 14 international organizations, four technical committees and one groundwater commission (not yet implemented). This article examines this institutional architecture by outlining the characteristics of cooperative arrangements established under treaties as a way of analyzing how the process of water governance takes place between riparian states. The large number of institutions contrasts with the modest number of joint actions and projects, which prompts questions about their role in the governance process, especially considering the lack of transparency and information about their performance. 相似文献
1000.
The objective of this article is to assess the potential for potable water savings in office buildings located in Florianópolis, southern Brazil. The embodied energy of four alternatives to reduce potable water demand, i.e., rainwater harvesting, greywater reuse, dual-flush toilets and water-saving taps, was also assessed. The analyses took into account the potable water end-uses for ten buildings. The potential for potable water savings by using rainwater, as well as, the rainwater tank sizing were estimated using computer simulation. As for greywater reuse, it was considered that greywater from lavatory taps could be treated and reused to flush toilets. The potential for potable water savings by using water-saving plumbing fixtures was estimated by considering the replacement of toilets and taps. In order to estimate the embodied energy in the main components, each system was dimensioned and embodied energy indices were applied. The main result is that the potential for potable water savings by using dual-flush toilets ranges from 21.6 % to 57.4 %; by reusing greywater, it ranges from 6.8 % to 38.4 %; by using rainwater, it ranges from 6.1 % to 21.2 %; by using water-saving taps it ranges from 2.7 % to 15.4 %. However, by considering the embodied energy, the average for the ten buildings indicates that dual-flush toilets are the best choice as it is possible to obtain water savings of 5.50 m3/month per GJ of embodied energy, followed, respectively, by water-saving taps, greywater reuse and rainwater usage. The main conclusion is that the assessment of embodied energy should be considered when evaluating potable water savings in buildings as it helps to identify the best alternatives to save more water while causing less environmental impact. 相似文献