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21.
B Roca C Vilar EV Pérez A Sáez-Royuela E Simón 《Canadian Metallurgical Quarterly》1996,25(17):803-804
OBJECTIVE: The incidence of Pseudomonas aeruginosa in HIV-infected patients has increased over the last years. We describe a case of pseudomonal breast abscess complicated with fatal septicemia in an AIDS patient. CASE REPORT: A 21-year-old woman was admitted for fever, chills, nausea, vomiting and pain in the breast. She had a swelling in the right breast of 3 days duration. HIV infection had been confirmed 6 years earlier. CD4 count was 2/mm3. Surgical drainage produced a blue-green purulent discharge which grew Pseudomonas aeruginosa on culture. Despite cloxacilin, then ceftazidime and amikacin, initial improvement was followed 2 weeks later by nodular pulmonary infiltration with cavitation. P. aeruginosa was recovered from sputum and blood cultures, but stepwise resistance developed and the patient died 3 months after admission. DISCUSSION: Breast abscesses are infrequent in nonlactating women. P. aeruginosa is rarely involved, even in HIV patients. Due to the risk of resistance, prompt administration of appropriate antibiotics is required. 相似文献
22.
L. M. da Cruz Simões 《Structural and Multidisciplinary Optimization》1992,5(1-2):76-83
Virtually all structural optimization based on system reliability was conducted considering continuous design variables. The solution of the reliability-based design problem is obtained by solving alternatively a reliability assessment problem and an optimal sizing program until the best reliability-based design occurs. The reliability assessment problem is formulated as a linearly constrained concave quadratic program. By introducing the concept of segmental members, the discrete optimum design is achieved based upon linear programming. Examples are solved by employing the proposed computational technique.Presented at NATO ASI Optimization of Large Structural Systems, Berchtesgaden, Germany, Sept. 23 – Oct. 4, 1991 相似文献
23.
Tiago Morais Alexandre L. Seabra Brbara G. Patrício Marta Guimares Mrio Nora Pedro F. Oliveira Marco G. Alves Mariana P. Monteiro 《International journal of molecular sciences》2021,22(11)
Visceral adipose tissue (VAT) metabolic profiling harbors the potential to disentangle molecular changes underlying obesity-related dysglycemia. In this study, the VAT exometabolome of subjects with obesity and different glycemic statuses are analyzed. The subjects (n = 19) are divided into groups according to body mass index and glycemic status: subjects with obesity and euglycemia (Ob+NGT, n = 5), subjects with obesity and pre-diabetes (Ob+Pre-T2D, n = 5), subjects with obesity and type 2 diabetes under metformin treatment (Ob+T2D, n = 5) and subjects without obesity and with euglycemia (Non-Ob, n = 4), used as controls. VATs are incubated in culture media and extracellular metabolite content is determined by proton nuclear magnetic resonance (1H-NMR). Glucose consumption is not different between the groups. Pyruvate and pyroglutamate consumption are significantly lower in all groups of subjects with obesity compared to Non-Ob, and significantly lower in Ob+Pre-T2D as compared to Ob+NGT. In contrast, isoleucine consumption is significantly higher in all groups of subjects with obesity, particularly in Ob+Pre-T2D, compared to Non-Ob. Acetate production is also significantly lower in Ob+Pre-T2D compared to Non-Ob. In sum, the VAT metabolic fingerprint is associated with pre-diabetes and characterized by higher isoleucine consumption, accompanied by lower acetate production and pyruvate and pyroglutamate consumption. We propose that glucose metabolism follows different fates within the VAT, depending on the individuals’ health status. 相似文献
24.
Maria Elizabeth Afonso de Magalhães M.Sc. Ph.D. student Matthieu Tubino Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1991,43(6):37-39
Gallium is normally obtained by direct electrolysis as a by-product from Bayer process residual liquor at an aluminum processing plant. However, to permit any net accumulation of the metal, the gallium concentration must be at least about 0.3 g/l in the liquor. This article describes a continuous process of extraction with organic solvents and rhodamine-B, followed by a re-extraction step into aqueous media. The final product is a solid containing up to 18 wt.% Ga in a solid mixture of hydroxides and oxides of gallium and aluminum. This final product can then be electrolyzed to recover the gallium more efficiently. 相似文献
25.
Identical twins pose a great challenge to face recognition due to high similarities in their appearances. Motivated by the psychological findings that facial motion contains identity signatures and the observation that twins may look alike but behave differently, we develop a talking profile to use the identity signatures in the facial motion to distinguish between identical twins. The talking profile for a subject is defined as a collection of multiple types of usual face motions from the video. Given two talking profiles, we compute the similarities of the same type of face motion in both profiles and then perform the classification based on those similarities. To compute the similarity of each type of face motion, we give higher weights to more abnormal motions which are assumed to carry more identity signature information. 相似文献
26.
Enterotoxigenic <Emphasis Type="Italic">Escherichia coli</Emphasis> strains bind bovine milk gangliosides in a ceramide-dependent process 总被引:2,自引:0,他引:2
Diarrhea caused by enterotoxigenic Escherichia coli (ETEC) is the main infectious disease of newborn calves. The first step of infection involves bacterial attachment to the
intestinal mucosa. This adhesion is mediated by fimbriae that recognize some glycoconjugates on the host cell surface, in
particular, several gangliosides. Because milk also contains gangliosides, these have been suggested to serve as ligands for
bacterial fimbriae and thus prevent the bacterial attachment to mucosa. The most relevant ETEC strains in calves, including
those with K99 and F41 fimbriae, were assayed to determine whether they are able to bind gangliosides isolated from several
stages of bovine lactation. Both GM3 and GD3, the main gangliosides of milk, were recognized by ETEC strains, although the
different fimbriae showed diverse levels of affinity. Unexpectedly, the adhesion to colostral gangliosides was considerably
weaker than that to gangliosides from the other stages of lactation. Because the carbohydrate moiety did not change and because
differences in the percentages of unsaturated FA and sphingosine between colostrum and other stages were observed, we conclude
that the differences in adhesion could be due to a different composition of the ganglioside caramide. 相似文献
27.
Comparative electrochemical studies of zinc chromate and zinc phosphate as corrosion inhibitors for zinc 总被引:4,自引:0,他引:4
The anticorrosive performance of two inhibitive pigments, zinc chromate and zinc phosphate, was compared using electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET) in pigment extracts in 0.1 M NaCl. It was observed that zinc was protected from corrosion in both extracts. In tests using hot dip galvanised steel painted with an epoxy primer incorporating the pigments, the SVET detected the anodic and cathodic distribution along the scribes, although no significant differences were observed among the various primers. On the contrary, EIS was able to distinguish processes occurring on the metal surface exposed by the scribe in different samples. For primers with anticorrosive pigment, a time constant at high frequencies was attributed to a layer of protective nature, probably formed by metal ions from the substrate and inhibitive ions leached from the anticorrosive pigments. 相似文献
28.
Bargaining is an effective paradigm to solve the problem of resource allocation. The consideration of factors such as bounded rationality of negotiators, time constraints, incomplete information, and complexity of dynamic environment make the design of optimal strategy for one-shot bargaining much tougher than the situation that all bargainers are assumed to be absolutely rational. Lots of prediction-based strategies have been explored either based on assuming a finite number of models for opponents, or focusing on the prediction of opponent’s reserve price, deadline, or the probabilities of different behaviors. Following the methods of estimating opponent’s private information, this paper gives a strategy which improves the BLGAN strategy to adapt to various possible bargaining situations and deal with multifarious opponents. In addition, this paper compares the improved BLGAN strategy with related work. Experimental results show that the improved BLGAN strategy can outperform related ones when faced with various opponents, especially the agents who frequently change their strategies for anti-learning. 相似文献
29.
M.?MelgosaEmail author R.?Huertas E.?Hita J.?M.?Roa F.?J.?Heredia J.?Alba M.?J.?Moyano 《Journal of the American Oil Chemists' Society》2004,81(4):323-330
A new color scale was developed from a broad data set of 1700 virgin olive oil samples over four crop seasons, which can be
considered highly representative of the whole color range of virgin olive oils available in Spain. This color scale provides
a new set of 60 color standards, improving the results achieved by the old 60-color standards proposed by the bromthymol blue
method. Seeking the greatest possibility of including a near match between colors of virgin olive oils and proposed standards,
we developed our new color scale using a recent uniform color space, with standards placed in a regular rhombohedral lattice
like the one employed by the Uniform Color Scales of the Optical Society of America. The average color difference between
each of the 1700 virgin olive oils and its nearest standard is reduced from 8.17 CIELAB units, using the bromthymol blue standards,
to 3.99 CIELAB units using the new standards. Within a color tolerance of 7.0 CIELAB units, 93.2% of our virgin olive oils
can be classified with the new standards, but only 59.1% with the bromthymol blue ones. In the interest of future adoption,
the performance of the new color standards should be tested by industry and researchers. 相似文献
30.
The adsorption of cobalt phthalocyanine dye onto activated carbon in a continuous stirred tank adsorber was studied. The variables investigated were: adsorbent mass, adsorbent particle size and fluid flowrate. Several models based on film, pore and surface diffusion were constructed and fitted to the experimental data. Experimental results showed: (i) the increasing importance of the film mass transfer resistance for increasing adsorbent loads; (ii) the increasing importance of the surface diffusion mechanism for increasing adsorbent loads; and (iii) the better discrimination among different models for higher adsorbent loads and lower flowrate. 相似文献