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61.
The effect of high pressure on the log reduction of six strains of Escherichia coli O157:H7 and five serovars of Salmonella enterica was investigated in tryptic soy broth, sterile distilled water, and commercially sterile orange juice (for Salmonella) and apple cider (for E. coli). Samples were subjected to high-pressure processing treatment at 300 and 550 MPa for 2 min at 6 degrees C. Samples were plated onto tryptic soy agar directly after pressurization and after being held for 24 h at 4 degrees C. At 300 MPa, little effect was seen on E. coli O157:H7 strains, while Salmonella serovars varied in resistance, showing reductions between 0.26 and 3.95 log CFU/ml. At 550 MPa, E. coli O157:H7 strains exhibited a range of reductions (0.28 to 4.39 log CFU/ml), while most Salmonella populations decreased beyond the detection limit (> 5-log CFU/ml reduction). The most resistant strains tested were E. coli E009 and Salmonella Agona. Generally, bacterial populations in fruit juices showed larger decreases than did populations in tryptic soy broth and distilled water. E. coli O157:H7 cultures held for 24 h at 4 degrees C after treatment at 550 MPa showed a significant log decrease as compared with cultures directly after treatment (P < or = 0.05), while Salmonella serovars did not show this significant decrease (P > 0.05). All Salmonella serovars tested in orange juice treated at 550 MPa for 2 min at 6 degrees C and held for 24 h showed a > 5-log decrease, while E. coli O157:H7 strains require a higher pressure, higher temperature, longer pressurization, or a chemical additive to achieve a 5-log decrease.  相似文献   
62.
Obesity is a strong predictive factor in the development of chronic disease and has now superseded undernutrition as a major public health issue. Chronic inflammation is one mechanism thought to link excess body weight with disease. Increasingly, the gut and its extensive population of commensal microflora are recognized as playing an important role in the development of obesity-related chronic inflammation. Obesity and a high fat diet are associated with altered commensal microbial communities and increased intestinal permeability which contributes to systemic inflammation as a result of the translocation of lipopolysaccharide into the circulation and metabolic endotoxemia. Various milk proteins are showing promise in the prevention and treatment of obesity and chronic low-grade inflammation via reductions in visceral fat, neutralization of bacteria at the mucosa and reduced intestinal permeability. In this review, we focus on evidence supporting the potential antiobesogenic and anti-inflammatory effects of bovine whey-derived lactoferrin and immunoglobulins.  相似文献   
63.
The present work aimed to compare the main ergogenic attributes of two commercialized stages (young and mature) of coconut water (CW) obtained from four coconut varieties. The changes of electrolytes and sugars in CW upon maturation were quantified by inductively coupled plasma mass spectrophotometer and high-performance liquid chromatography, respectively. Based on the electrolyte profiling, potassium yielded the highest amount (ranging from 237.41 to 361.20 mg/100 mL) followed by sodium, magnesium, calcium, iron, manganese, copper, selenium, and zinc across all the maturity stages tested. For sugars, there were lower amounts of fructose and glucose, but a higher amount of sucrose with the maturation of the fruits. In conclusion, the amount of beneficial nutrients in the form of sugars and minerals was higher than that of young CW, and the ergogenic attributes of mature CW especially from MATAG variety (M-MATAG) were the best to be exploited further in the development of natural energy drinks.  相似文献   
64.
BACKGROUND: Adolescents residing in low-income public housing developments in inner-city regions may be particularly vulnerable to a variety of risk factors associated with cigarette smoking. OBJECTIVE: To elucidate the aetiology of cigarette smoking among adolescents living in public housing developments. DESIGN, SETTING, AND SUBJECTS: We examined predictors of smoking from four domains: background characteristics, social influences, behavioural control, and psychosocial characteristics using a sample of seventh graders (mean age 12.9 years) who reside in public housing developments in New York City (n = 624). The addresses of participants in a larger investigation of the aetiology and prevention of smoking were checked to determine if they lived in one of 335 public housing developments in New York City. All participants living in public housing developments were included in the current study. MAIN OUTCOME MEASURES: African-American and Hispanic students completed questionnaires about their cigarette use, social pressures to smoke, smoking attitudes, smoking knowledge, and smoking resistance skills. Students also provided information on demographic and behavioural control (such as church and school attendance). RESULTS: Logistic regression analyses indicated that social influences from friends and family members predicted smoking. Psychosocial characteristics such as advertising resistance skills, anti-smoking attitudes, and refusal skills lowered the odds of smoking. CONCLUSIONS: These findings suggest that smoking prevention approaches targeted at these young people should increase their awareness of social pressures to smoke, correct misperceptions about the prevalence of smoking among friends, and teach relevant psychosocial skills.  相似文献   
65.
Summary Gas chromatographic and gas chromatographic-mass spectrometric examination of the aroma components of canned plums obtained by both atmospheric distillation and headspace techniques showed them to be both quantitatively and qualitatively different from those of fresh plums. 25 components were identified, the major ones being 3-hydroxy-butan-2-one, benzaldehyde, nonanal and 2-furaldehyde. Benzaldehyde and nonanal together with benzyl acetate are believed to make a significant contribution to the aroma of canned plums.
Die Geschmackskomponenten der Pflaume:Eine Untersuchung über die flüchtigen Inhaltsstoffe der Pflaumen in Dosen
Zusammenfassung Gaschromatographische und gaschromatographische-massenspektrometrische Analysen zeigten, daß die Aromastoffe der dosenkonservier ten Pflaumen, sowohl durch atmosphärische Destillation als auch nach der Kopfraum-Technik erhalten, quantitativ sowie qualitativ verschieden von denen der frischen Pflaumen sind. Es wurden 25 Komponenten identifiziert, darunter als Hauptbestandteile 3-Hydroxy-butan-2-on, Benzaldehyd, Nonanal und 2-Furfurol. Benzaldehyd und Nonanal zusammen mit Benzylacetat stellen einen bedeutsamen Beitrag zum Aroma dosenkonservierter Pflaumen dar.
  相似文献   
66.
The fate of tritiated 25-hydroxycholecalciferol administered intramuscularly is compared in two groups of sheep raised either in confinement or outdoors. The uptake of radioactivity was more rapid by the indoor than the outdoor sheep. The assessment of radioactivity in plasma and tissues of outdoor sheep dosed with either tritiated 25-hydroxycholecalciferol or with equivalent amounts of tritiated cholecalciferol revealed that plasma and tissue radioactivity were substantially higher in sheep dosed with tritiated 25-hydroxycholecalciferol than in sheep dosed with tritiated cholecaliferol. Three days after the administration of tritiated cholecalciferol virtually all plasma radioactivity was associated with 25-hydroxycholecalciferol.  相似文献   
67.
Collaborative work to determine the amino acid, taurine, urea and ammonia contents of a standard mixture of amino acids and of blood plasma from a preruminant and a ruminant calf was carried out at four laboratories to assess the accuracy of the ion-exchange column chromatographic technique. Samples of blood plasma were deproteinised by the organising laboratory and by the collaborating laboratories using their own methods. For the standard amino acid mixture the mean absolute deviation was 0.036 of the true concentration. This compared favourably with results from previous collaborative trials on protein hydrolysates. The mean absolute deviations were 0.192 for preruminant calf blood deproteinised by the organising laboratory and 0.159 for blood deproteinised by the collaborating laboratories. Comparable values for ruminant calf blood were 0.149 and 0.117, respectively. These results were much poorer than those obtained for protein hydrolysates and possible explanations are put forward for these different degrees of precision.  相似文献   
68.
Changes in the fish muscle from cod ( Gadus morhua ) and haddock ( Melanogrammus aeglefinus ) were investigated by high-resolution NMR and magnetic resonance imaging (MRI). Water- and salt-soluble extracts from fish stored at −20°C and −30°C were analysed by high-resolution proton NMR and enabled the identification of metabolites including trimethylamine oxide, trimethylamine (TMA) and dimethylamine. It was not possible to detect formaldehyde by NMR either in the stored fish samples or in spiked water or salt extracts even at high levels of formaldehyde addition, probably due to polymerisation. Systematic and controlled storage trials indicated the presence of dimethylamine at around 9 months for samples stored at −20°C, whereas no changes were detected at the control storage temperature of −30°C. A comparison of cod and haddock fillets stored for 1 year at −20 and −30°C confirmed the production of dimethylamine only in cod stored at −20°C. It was interesting to note that ‘fresh’ cod and haddock samples purchased from a local supermarket showed high levels of TMA indicating a breakdown of trimethylamine oxide to TMA by bacteria. TMA was not detected in the fish fillets especially obtained for the storage trials. MRI of fresh cod and fish stored at −8 and −30°C indicated that the fish half stored at −8°C exhibited dense lines or arches which are indicative of gaps in the tissue due to possible breakdown of the connective tissue. The images of fish stored at −30°C did not indicate any differences compared with the fresh fish. MRI also showed the presence of frozen and unfrozen areas in the fish non-destructively.  相似文献   
69.
The toxicity of the first eight primary alcohols and of four secondary alcohols was compared in a wild-type strain (having active ADH) and an ADH-negative mutant. Differences between LC50 measured in the two strains allowed an evaluation of the biological activity of the enzyme. In vitro, ADH is mainly active on secondary alcohols, while in vivo its main role is the detoxification and metabolism of ethanol. These observations suggest that originally ADH was involved in unknown metabolic pathways and that its utilization in ethanol metabolism could be a recent event.  相似文献   
70.
A patient with documented ZE syndrome responded to intravenous magnesium infusion by increased gastric acid output and increased serum gastrin concentration. A patient with acid hypersecretion but no gastrinoma had no substantial alteration in acid output or serum gastrin concentration following magnesium administration. This suggests that magnesium caused gastrin to be released from a gastrinoma.  相似文献   
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