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Malnutrition is common in chronic hemodialysis (CHD) patients and is strongly related to increased morbidity and mortality. Among the various approaches to treat malnutrition in this patient population, intradialytic parenteral nutrition (IDPN) is the treatment of choice for a small but important percentage of malnourished CHD patients. However, the new revised policies relating to IDPN reimbursement by Medicare in the US have made it very difficult to qualify patients for this potentially useful therapy. This restrictive policy was adopted mainly because there are no clear data that support IDPN use or efficacy. Studies to date in the literature do not provide clear documentation of the benefits of IDPN or their cost-effectiveness. The purpose of this review is to critically evaluate studies relating to the use of IDPN as a potential therapy to treat malnutrition in CHD patients and to discuss potential trials to prove its cost-effectiveness.  相似文献   
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Human rotaviruses are the most important etiologic agents of acquired diarrhea in infants and young children worldwide. Early diagnosis is essentialfor effective patient treatment. The latex agglutination (LA) assays for rotavirus diagnosis are rapid, inexpensive, and the most widely used to screen specimens. The performance of the LA Rotagen (Biokit S.A., Barcelona, Spain) was evaluated for rotavirus detection infecal samples of outpatients with acute gastroenteritis. This assay was compared with the enzyme immunoassay (EIA) EIARA (Bio-Manguinhos, Rio de Janeiro, Brazil). From January to October 2000, 285 fecal specimens were analyzed. Forty-four samples (15.4%) were reactive, 214 (75.4%) were nonreactive, and 27 (9.5%) were indeterminate by LA. All LA-positive samples were positive by EIA, and 2 LA-negative samples were positive by EIA. Of specimens indeterminate by LA, 67% were positive by EIA. The sensitivity, specificity, and accuracy of LA were 69%, 100%, and 93%, respectively. These results indicate that assay is as sensitive and specific as the EIA, and it could be applied on a large scale for screening stool specimens in suspected rotavirus diarrhea. However, the indeterminate results must be confirmed by other methods, such as EIA.  相似文献   
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Carbapenem-resistant Acinetobacter baumannii isolates were obtained from eight patients in two hospitals in Curitiba, Brazil. The isolates were multiresistant, belonged to a single strain, and produced the OXA-23 carbapenemase. Treatment options were limited, although the isolates were susceptible to polymyxin B in vitro. The strain contributed to the deaths of five patients.  相似文献   
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A series of bulk and solution (in toluene) copolymerizations of butyl acrylate/methyl methacrylate were performed independently at two laboratories. The runs were at elevated temperatures ranging from 90 to 140 °C conducted to high conversion levels, and samples were characterized for conversion, cumulative copolymer composition and number‐ and weight‐average molecular weights and distribution. Variation of the comonomer feed composition, temperature, and the solvent, initiator and chain transfer agent concentrations was studied. Using a mechanistic model, conversion data were predicted to high conversions using terminal model kinetics at 90 and 115 °C. The copolymer composition data conformed to the terminal kinetic model over the entire temperature range. Solvent effects were reflected by changes in the butyl acrylate rate constants.

Composition vs. conversion. Effect of feed composition for runs at 140 °C.  相似文献   

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BACKGROUND: Anaphylactic reactions caused by bites of the European pigeon tick Argas reflexus are repeatedly reported. This soft-backed tick is a parasite of wild pigeons colonizing urban buildings and houses. Occasionally the ticks can bite human beings, inducing anaphylactic reactions in sensitized patients. OBJECTIVE: Our aim was to characterize the major allergen implicated in a series of anaphylactic reactions caused by Argas bites and to produce the allergen as recombinant protein for diagnostic purposes. METHODS: Protein extracts were prepared from whole A reflexus bodies, and IgE immunoblots were performed with sera from 13 patients who had an anaphylactic reaction with pigeon tick bites. A cDNA expression library was constructed from whole ticks and screened with a polyclonal rabbit antiserum raised against the major allergen. RESULTS: The cDNA coding for the dominant allergen Arg r 1 could be isolated. It encodes a protein belonging to the lipocalin family. Allergenicity of the recombinant Arg r 1 was confirmed by immunoblot, ELISA, and intradermal skin tests. CONCLUSION: The dominant allergen of A reflexus has been isolated and the corresponding cDNA cloned. The recombinant protein, a lipocalin, was expressed in Escherichia coli and was shown to be immunoreactive in vitro and in vivo. Recombinant Arg r 1 was used as a diagnostic tool in a series of anaphylactic reactions caused by pigeon tick bites.  相似文献   
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The colonization by the probiotic Lactobacillus casei subsp. rhamnosus Lcr35 of the gastrointestinal tracts of mice and humans was studied. The mice were orally given 10(9) CFU of Lcr35 either once or three times at 24-h intervals. A 16S ribosomal nucleic probe used in hybridization assays detected Lcr35 in the feces of mice for up to 3 days after the feeding, at a level of 10(8) to 10(9) CFU/g of feces. In the human assay, 12 healthy volunteers were enrolled in a randomized trial and ingested Lcr35 at a dosage of 10(8) or 10(10) or 10(12) CFU every day for 7 days. Then, after a 3-week posttreatment period, there was a second intake period similar to the first one. Analysis of fecal samples showed significant increases in the number of lactobacilli during the first intake period, whatever the dose given. The greatest increases were observed in subjects harboring the lowest indigenous population of Lcr35-like bacteria. During the 3-week posttreatment period, the number of CFU slightly decreased over time, and an increase, although not a statistically significant one, was observed during the second test period. These findings suggest that Lcr35 is able to survive within the gastrointestinal tract.  相似文献   
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