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51.
Acute, exsanguinating hemorrhagic cystitis secondary to cyclophosphamide therapy, radiation therapy, or an infiltrating bladder tumor may be managed successfully with intravesical Formalin therapy. The indications for its use, the technique, success rates, and complications are discussed. This treatment was effective in 14 of 16 patients in the present series and 79 of 90 cases reported in the literature. Dilutions of 4% or less were as effective as a 10% dilution and were associated with far fewer complications. The early use of Formalin in the treatment of intractable hemorrhagic cystitis is recommended.  相似文献   
52.
Lactobacillus (L.) helveticus H9 is a probiotic strain that can produce antihypertensive peptides during milk fermentation. This study analysed the dynamics of skim milk fermentation by L. helveticus H9 by ultra‐performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry (UPLC/Q‐TOF MS). A total of 1992 metabolites were detected from all of the fermented samples in the LC‐MS analysis by multivariate statistical analysis. Metabolites with variable importance in projection (VIP) values ≥2 were considered differentially abundant among samples and were responsible for the unique taste and nutritional and functional qualities of fermented milk. Valine, threonine, l ‐methionine, tyrosine, asparagine and leucine were the predominant amino acids produced during fermentation, and their quantities changed remarkably during the fermentation process. Citric acid and uric acid were the major, and only detectable, organic acids. Some intermediate metabolites, such as N‐acryloylglycine and nicotinamide‐N‐oxide, were also detected. Moreover, certain oligopeptides such as Val‐Leu, Lys‐Gly, Ala‐Glu, Asp‐Ser, Leu‐Pro and Val‐Phe‐Ala were not detected until the middle and late fermentation periods. This study demonstrated dynamic metabolic changes, providing a strong foundation for deciphering the physiological and biochemical mechanisms of the fermentation process.  相似文献   
53.
Lactobacilli are widely used as starter cultures or probiotics in yoghurt, cheese, beer, wine, pickles, preserved food, and silage. They are generally recognized as safe (GRAS). However, recent studies have shown that some lactic acid bacteria (LAB) strains carry antibiotic resistance genes and are resistant to antibiotics. Some of them may even transfer their intrinsic antibiotic resistance genes to other LAB or pathogens via horizontal gene transfer, thus threatening human health. A total of 33 Lactobacillus strains was isolated from fermented milk collected from different areas of China. We analyzed (1) their levels of antibiotic resistance using a standardized dilution method, (2) their antibiotic resistance gene profiles by polymerase chain reaction (PCR) using gene‐specific primers, and (3) the transferability of some of the detected resistance markers by a filter mating assay. All Lactobacillus strains were found to be resistant to vancomycin, but susceptible to gentamicin, linezolid, neomycin, erythromycin, and clindamycin. Their susceptibilities to tetracycline, kanamycin, ciprofloxacin, streptomycin, quinupristin/dalfopristin, trimethoprim, ampicillin, rifampicin, and chloramphenicol was different. Results from our PCR analysis revealed 19 vancomycin, 10 ciprofloxacin, and 1 tetracycline‐resistant bacteria that carried the van(X), van(E), gyr(A), and tet(M) genes, respectively. Finally, no transferal of the monitored antibiotic resistance genes was observed in the filter mating assay. Taken together, our study generated the antibiotic resistance profiles of some milk‐originated lactobacilli isolates and preliminarily assessed their risk of transferring antibiotic gene to other bacteria. The study may provide important data concerning the safe use of LAB.  相似文献   
54.
Soymilk was subjected to various heat treatments at 90, 120 and 140 °C for various lengths of time. The colour and flavour of the soymilk samples were evaluated by a sensory panel consisting of eight semi‐trained assessors on (1) a 9‐unit hedonic scale, with analysis based on the assumption that the units are equidistant, and (2) a 15‐point hedonic ‘Smiley’ pictorial scale, the results being analysed non‐parametrically. The proportion (%) of ratings higher than or equal to/higher than the overall median of the samples was used as a rigorous estimate of product quality. These values were used to determine the colour and flavour changes in heated soymilk and their temperature dependence. The Z‐values derived from the parametric and non‐parametric analyses were in close agreement, ranging from 31 to 33 °C and from 30 to 32 °C for colour and flavour respectively. © 2000 Society of Chemical Industry  相似文献   
55.
Recent studies aimed at the development of macrocyclic oligomers as the intermediates for the preparation of high-performance polymers are reviewed. Efficient methods for the preparation of a range of cyclic oligomers, such as aryl ether ketones, aryl ether phthalazines, aryl ether isoquinolines, aryl ether phthalazinones, and arylene sulfides, have been developed. Cyclization was achieved via a nucleophilic aromatic substitution reaction under high-dilution conditions. The cyclic aryl ether oligomers undergo a facile ring-opening polymerization to form high molecular weight polymer. Cyclic oligomers containing an aromatic sulfide linkage also undergo a facile free-radical ring-opening polymerization to form high molecular weight polymers which can be amorphous or crystalline. Due to their low molecular weights, these cyclic oligomers have very low melt viscosities which makes them attractive intermediates for a variety of applications for which the conventionally prepared high molecular weight polymers would not be suitable.  相似文献   
56.
Protein was extracted from okara at pH 9.0 and 80 °C for 30 min, giving a recovery of 53% protein. The extracted protein was isolated by isoelectric precipitation at pH 4.5, and the dried, defatted protein isolates (prepared at 25 and 80 °C) had over 80% protein.

The okara protein isolates have essential amino acid profiles similar to the FAO scoring pattern, and high in vitro protein digestibility, with methionine and cysteine as the limiting amino acids. Polyacrylamide gel electrophoresis in sodium dodecyl sulfate showed that okara protein isolates had a large quantity of high molecular weight components suggesting protein aggregation. Differential scanning calorimetry and hydrophobicity data suggested extensive protein unfolding in the okara products.

Okara protein isolates had lower solubility than a commercial soy protein isolate at both acidic and alkaline pH, probably due to protein aggregation. Other functional properties, including emulsifying, water and fat binding, and foaming properties, were found to be comparable to the commercial soy isolate.  相似文献   

57.
Eighteen and 23 FAA components were detected in the cyst wall and cyst fluid of E granulosus, respectively, by using automatic amino acid analyzer. The concentrations of most of the determined FAA were higher in the cyst fluid than those in the cyst wall, especially the taurine was 5-fold higher. Mebendazole treatment resulted in an increase in the concentration of alanine, valine, lysine, and taurine in both cyst wall and cyst fluid, the most notable being the alanine in the cyst wall. The results are interpreted as a coupling of glycolysis and amino acid metabolism, suggesting an involvement of FAA metabolism in the mechanism of Meb action.  相似文献   
58.
OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation.  相似文献   
59.
The five independent stiffness constants, C11, C33, C44, C66, and C13, and the axial and transverse thermal expansivity of unidirectional gel-spun polyethylene fiber reinforced composites have been measured as functions of fiber volume fraction Vf. The axial extensional modulus C33 and axial Poisson's ratio v13 follow the rule of mixtures, while the axial shear modulus C44, transverse shear modulus C66, and transverse plane-strain bulk modulus Ct ( = C11C66) obey the Halpin-Tsai equation. Extrapolation to Vf = 1 gives the five stiffness constants of gel-spun polyethylene fiber. The tensile property of the fiber is highly anisotropic, with the axial Young's modulus about 40 times higher than the transverse Young's modulus. In contrast, the axial shear modulus exceeds the transverse shear modulus by only 5%. A similar treatment of the thermal expansivity data in terms of the Schapery equations gives an axial thermal expansivity of −1.25 × 10−5 K−1 and a transverse thermal expansivity of 11.7 × 10−5 K−1 for the fiber.  相似文献   
60.
The present study examined the antioxidant activity of black tea theaflavins and catechin derivatives in canola oil. Oxidation was conducted at 95°C by monitoring the oxygen consumption and decreases in the linoleic and α-linolenic acids of canola oil. All were tested at a concentration of 0.5 mM. Catechins, including (−)-epicatechin, (−)-epicatechin gallate, (−)-epigallocatechin, and (−)-epigallocatechin gallate (EGCG), were more effective than theaflavins, namely, theaflavin-1, theaflavin-3-gallate, theaflavin-3′-gallate, and theaflavin-3,3′-digallate (TF3), against the lipid oxidation of canola oil. Among the four theaflavins, TF3 was the most effective, whereas among the four catechins, FGCG was the most potent. Under the same conditions, all theaflavins and catechins were more powerful than BHT as an antioxidant in heated canola.oil. Little or no difference in antioxidant activity was observed between each catechin and epimer pair. Methylation of the 3′-OH led to a significant loss of antioxidant activity of the catechins.  相似文献   
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