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G N Krywolap W Fischlschweiger C L Dabirsiaghi B S Margaret 《Journal of medical microbiology》1991,35(6):338-344
Eubacterium yurii subsp. yurii is an anaerobic, gram-positive rod. On isolation E. yurii forms cellular arrangements resembling test-tube brushes (TTB). Although TTB decreased in size and number on repeated laboratory subculture in enriched media, media poor in available iron enhanced formation of these. Plasmids were not demonstrated, even after chloramphenicol enhancement. To characterise the nature and possible physiological roles of the structures of the TTB, they were examined by transmission electronmicroscopy (TEM) with thin-section, negative-staining, shadow-casting, freeze-etching and freeze-fracturing techniques, and by scanning electronmicroscopy (SEM). Previous studies by phase-contrast microscopy revealed an amorphous core, the size of which varied in direct proportion to the number of associated bacterial cells. Thin sections of the TTB showed a gram-positive cell wall with additional surface layers. Negative staining, shadow casting and freeze etching revealed a surface layer comprising subunits in tetragonal array (P4 symmetry). Shadow casting showed also that the outermost layer of the cells was composed of fibrillar structures closely associated with but distinct from, the tetragonal layer. The fibrils extended from the cell surface in clumps or strands. The presence of these fibrils was confirmed by the freeze-fracture technique and SEM. Chemical analysis of the core material of the TTB showed it to be low in carbohydrate (0.06%) and protein (0.2%). Energy-dispersive X-ray spectrometry showed that the core was composed mostly of iron.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Margaret A. Chambers 《Journal of clinical nursing》1998,7(3):201-208
? This paper focuses on some issues in the assessment of clinical practice of particular interest to the author. ? The assessment of students of nursing in clinical practice is acknowledged as a long-standing and difficult problem. ? There is little consensus as to what is meant by the term competence when applied to clinical nursing practice, making the assessment of clinical practice a mainly subjective process. ? The English National Board (1989) has distinguished the term mentor as meaning counsellor and guide, nevertheless the roles of mentor and assessor are frequently confused. ? It is suggested that nurses are equally accountable for the accurate assessment of student nurses' clinical skills as they are for their own practice. ? The validity and reliability of tools used to assess clinical practice are difficult to establish, making objective assessment complex at best, and impossible at worst. ? The assessment of the reflective process has been suggested as one way out of the dilemma, but the ability to think and to write does not necessarily translate into competent clinical practice. 相似文献
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Bob Mash Di Powell Felicity du Plessis Unita van Vuuren Margaret Michalowska Naomi Levitt 《Suid-Afrikaanse tydskrif vir geneeskunde》2007,97(12):1284-1288
BACKGROUND AND AIMS: In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. METHODS: The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. RESULTS: Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. CONCLUSION: Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year. 相似文献
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The purpose of this pilot study was to determine the effects of the addition of coping skills training for obese multiethnic parents whose overweight children were attending a weight management program. At 6 months, parents in the experimental group had significantly lower body mass index (BMI) and body fat percentage (BFP) and higher numbers of pedometer steps compared with those in the control group. Parents in the experimental group also demonstrated significant improvement in interpersonal relationships, behavior control, and stress management compared with those in the control group. Children in the experimental group demonstrated trends toward decreased BMI and BFP and increased pedometer steps. 相似文献