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51.
Stander MA Bornscheuer UT Henke E Steyn PS 《Journal of agricultural and food chemistry》2000,48(11):5736-5739
Ochratoxin A (OTA) is a nephrotoxic and carcinogenic mycotoxin. The toxin is a common contaminant of various foods and feeds and poses a serious threat to the health of both humans and animals. A number of commercial hydrolases were screened for the ability to degrade OTA to nontoxic compounds. A crude lipase from Aspergillus niger (Amano A) proved to substantially hydrolyze OTA to the nontoxic OTalpha and phenylalanine, as confirmed by HPLC with fluorescence detection. The enzyme was purified by anion exchange chromatography to homogeneity. Activity staining of the purified enzyme with alpha-naphthyl acetate/Fast Red revealed only one band exhibiting hydrolytic activity. The specific activity of the purified enzyme toward OTA was 2.32 units/mg. 相似文献
52.
53.
Mciza Z Goedecke JH Steyn NP Charlton K Puoane T Meltzer S Levitt NS Lambert EV 《Public health nutrition》2005,8(5):509-519
OBJECTIVE: We sought to validate questionnaires concerning body image perception, body size dissatisfaction and weight-related beliefs in multi-ethnic South African mothers and their daughters. SETTINGS AND SUBJECTS: Girls attending primary school (ages 9-12 years, n = 333) and their mothers (n = 204) were interviewed regarding their demographics and body image. Weight, height and skinfold thicknesses were measured. Body image questions and body mass index (BMI) were compared with silhouettes adapted from the Pathways Study for girls and Stunkard's body image figures for mothers. A Feel-Ideal Difference (FID) index score was created by subtracting the score of the silhouette selected by the participants as 'Ideal' from the one selected as most closely representing their current appearance or 'Feel'. We hypothesised that a higher FID index score would be associated with greater body size dissatisfaction. RESULTS: BMI percentiles in girls (r = 0.46, P < 0.05) and BMI in mothers (r = 0.68, P < 0.05) were positively correlated with the selected silhouettes based on size. Participants who reported feelings of being 'fat' and those who perceived that their family and friends were more dissatisfied with their body size had significantly higher FID index scores. Scores were lower in black than white girls (all P<0.05). No differences were found in FID index scores between ethnic groups of mothers. Internal reliability of the 'thin' and 'fat' belief constructs for girls was demonstrated by standardised Cronbach's alpha values > or = 0.7. CONCLUSION: Silhouettes, FID index, 'fat' and 'thin' belief constructs (in girls) are age-appropriate, culturally sensitive and can be used in further intervention studies to understand body image. 相似文献
54.
Cruz R Steyn P Collins D Powers B Urigh J 《Journal of the American Animal Hospital Association》2011,47(4):229-235
The objective of this article was to compare radiography, planar bone scintigraphy, and single-photon emission computed tomography (SPECT) to determine the size of osteosarcomas in long bones of dogs. Ten dogs with osteosarcoma in six radii, two humeri, one tibia, and one ulna were evaluated. Macroslides, mediolateral radiographs, planar scintigrams, and sagittal images from SPECT scans were used to obtain measurements. On the scintigraphic images, the edges of the tumor were established using the activity profile imaging tool. The radiographic magnification was factored. The mean percentage of tumor size overestimation was 9.29% on mediolateral radiographs, 5.35% on planar scintigrams, and 33.25% on SPECT images. The correlation coefficient adjusted for sample size was significantly higher (P<0.01) for technetium 99m ((99m)Tc) hydroxyethylene diphosphonate (HDP) (75.5%) and radiography (61.3%) compared with indium 111-vitamin B(12) (28.3%). The correlation coefficient for (99m)Tc-HDP was higher than that obtained for radiographs; however, statistical difference between the two variables was not demonstrated (P>0.05). (99m)Tc bone scan is a good estimator of intramedullary size of osteosarcoma in long bones when the activity profile tool to determine the margin of the tumor is used. 相似文献
55.
Summary The aim of the study was to determine whether isolates ofFusarium oxysporum Schlecht. produce fusaric acid in culture and whether mycelial growth can be used as a measurement of fusaric acid production.
Three isolates produced significant levels of fusaric acid in culture filtrate, the maximum concentration being reached after
18 days, whereafter it remained constant. Mycelial growth could not be used to measure or estimate the production of fusaric
acid. Growth curves from specific isolates could be used to determine the concentration of fusaric acid in culture filtrate
after specific lengths of time. 相似文献
56.
OBJECTIVES: The present paper aims to review and report on the current and predicted future public health nutrition workforce in South Africa. Additionally, it examines ways in which the Department of Health (DOH) is striving to meet the increasing burden of nutrition-related diseases in South Africa. METHODS: The primary sources of data used for the review were reports from the Census office, South African health reviews, mortality and morbidity statistics, and documents from the Health Professions Council of South Africa. RESULTS: There are fewer than 2000 registered dietitians in South Africa and fewer than 600 of them work in the public health sector. Furthermore, professional nurses - who are the backbone of the primary health-care system and deliver the rudiments of basic nutritional care - are not being trained in sufficient numbers to meet population growth; in 2004 there was only one nurse per 4000 persons. This situation is aggravated by the growing burden of conditions associated with both overnutrition and undernutrition, as well as the enormous demands of the HIV/AIDS epidemic. The DOH is striving to meet these increasing needs by means of the Integrated Nutrition Programme as well as a National Human Resources Plan which includes numerous strategies to improve the quantity and quality of health professionals' training, including dietitians and nutritionists. This plan includes the objective of increasing the public health nutrition workforce to more than 250 newly trained dietitians and nutritionists per annum by 2010. 相似文献
57.
A number of bacterial isolates which could not be identified as either Salmonella or Citrobacter by conventional biochemical tests and could not be typed as Salmonella with available antisera, were further examined biochemically and by lysis with phage Felix 0.1. Glycerol-positive salmonellae and lysine-positive citrobacters were encountered, which could be confused with the other genus, but when the reactions of such strains were examined in the other tests, accurate identifications could be done. Of the tests examined, glycerol fermentation, the beta-galactosidase test, lysine decarboxylation, sorbose fermentation, galacturonate fermentation and lysis by the phage could be used in the differentiation. These tests in combination, rather than 1 or 2 single tests gave reliable and conclusive differentiation. 相似文献
58.
Phillip F. Steyn BSc BVSc MRCVS David Schmitz DVM MS Jeffrey Watkins DVM MS Jay Hoffman BS DVM 《Veterinary radiology & ultrasound》1989,30(3):125-127
Chronic proliferative synovitis is an insidious condition affecting the metacarpophalangeal joints of horses. It results in proliferation of the synovium in the dorsal pouch of the joint in question. Treatment involves surgical excision, thus confirmation of the lesion is important. Classically this has been achieved by means of positive-contrast arthrography, but this article addresses the attributes of ultrasonography, a less invasive imaging technique. 相似文献
59.
Westfall DS Twedt DC Steyn PF Oberhauser EB VanCleave JW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(5):467-470
We have reported tablet-induced focal esophagitis and esophageal stricture formation in cats. The proposed mechanism is thought to be abnormal esophageal tablet retention resulting in focal esophagitis with subsequent stricture formation. The objective of this study was to evaluate the passage of tablets and capsules when given alone (dry swallow) and when followed by a water bolus (wet swallow) to determine if this could, in part, explain the esophageal stricture formation we have observed in cats. Fluoroscopy was used to evaluate tablet or capsule passage after administration. The percentage of dry tablet swallows that successfully passed into the stomach was 0.0% at 30 and 60 seconds, 6.7% at 90 seconds, 13.3% at 120 seconds, 26.7% at 180 and 240 seconds, and 36.7% at 300 seconds. Wet tablet swallows successfully passed 90.0% of the time at 30 seconds, 93.3% of the time at 60 seconds, and 100.0% of the time thereafter. The percentage of dry capsule swallows that successfully passed was 16.7% at each time interval. Wet capsule swallows successfully passed 96.7% of the time at 30 seconds and 100% of the time thereafter. For each time interval, wet swallows achieved significantly greater percentage passage into the stomach when compared to dry swallows (P < .05). This study shows that tablets or capsules given by dry swallow have prolonged retention in the esophagus compared to those given by wet swallow. On the basis of this study, we recommend the routine administration of a water bolus to cats receiving tablets or capsules PO to facilitate esophageal clearance. This practice may help prevent medication-associated esophagitis or stricture formation. 相似文献
60.
Summary A major objective of plant breeding programmes in semi-arid conditions is the selection of more drought-tolerant plant material.
An irrigation system has been developed to assist in water use and drought tolerance screening studies of potato genotypes
in the confined space of a rain shelter. The line-source principle was used as a departure point for the design of an irrigation
boom, attached to the roof structure of a rain shelter. Five water regimes were achieved by using nozzles that differed in
discharge rate and three genotypes per rain shelter were evaluated simultaneously.
Crop production functions could be established for the different genotypes. The system shares some disadvantages of the typical
line-source, such as the simultaneous irrigation of all plots and water treatments are not randomised. The main advantage
above traditional plot systems, which would use drip or micro irrigation under rain shelters, is the ease of management. 相似文献