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Exfoliative toxin D (ETD) was identified recently as a new exfoliative toxin serotype. Like other exfoliative toxins, ETD induces intra-epidermal cleavage through the granular layer of the epidermis of neonatal mice. The distribution of ETD production was investigated in Staphylococcus aureus isolates from infected and colonised patients in France. The etd gene was found in 55 (10.5%) of 522 isolates tested. Isolates responsible for bullous impetigo and generalised staphylococcal scalded skin syndrome did not harbour etd, but etd was significantly more frequent in isolates causing cutaneous abscesses and furuncles. Most etd- and Panton-Valentine leukocidin-positive strains belonged to the clone of community-acquired methicillin-resistant S. aureus spreading currently throughout France.  相似文献   
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AIM--To investigate the distribution of cytokeratins 10, 13, 14 and 19 in biopsy specimens taken from acetowhite and non-acetowhite areas of the cervix. METHOD--Cervical biopsy specimens were taken from both acetowhite and non-acetowhite areas from 44 patients who presented with abnormal cervical cytology. The specimens were snap frozen in liquid nitrogen and multiple sections taken from each specimen. Staining was performed for cytokeratins 10, 13, 14, 19 and NADPH diaphorase enzyme. The areas of each section positive for the various markers were measured. RESULTS--Cytokeratin 10 positive cells were greatly increased in number in acetowhite biopsy specimens compared with non-acetowhite samples (45.1% v 2.8%; p < 0.0001). Cytokeratin 19 was also increased, but to a lesser extent (17.8% v 5.5%; p < 0.0001). In contrast, the almost universal expression of cytokeratin 13 was reduced in acetowhite biopsy specimens (86.2% v 96.9%; p < 0.0001). Cytokeratin 14 was found diffusely in the basal region of the stratified squamous epithelium and was marginally more apparent in the acetowhite biopsy specimens (p = 0.04). CONCLUSION--It is suggested that the presence of cytokeratin 10 may be an essential requirement for the formation of acetowhite change in association with the cellular swelling caused by acetic acid.  相似文献   
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The meaning of spirituality: a literature review   总被引:1,自引:0,他引:1  
This paper presents a literature review in relation to the meaning of spirituality. It is proposed that meeting the spiritual needs of patients is a fundamental part of providing holistic nursing care, but that the assessment and meeting of those needs is impeded by inadequate definitions and conceptual frameworks. It should not be assumed that spirituality is either synonymous, or coterminous, with religion, and it is suggested that to adopt this restrictive view is unhelpful in the provision of individualized care. Reflection on the literature reveals that the self, others and 'God' provide the key elements within a definition of spirituality, and that other emerging themes namely meaning, hope, relatedness/connectedness, beliefs/belief systems and expressions of spirituality, can be articulated in the context of those three key elements. In particular, it is proposed that the nature of 'God' may take many forms and, essentially, is whatever an individual takes to be of highest value in his/her life. It is suggested that the themes emerging from the literature can be utilized as a framework to give practitioners and researchers a direction for future exploration of the concept of spirituality.  相似文献   
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A widely held assumption is that postpyloric intubations occur more often with weighted than with unweighted nasally inserted feeding tubes. This randomized, prospective study compared the frequency of duodenal intubations using weighted and unweighted nasoenteric feeding tubes. One hundred sixteen patients had either weighted (61 patients) or unweighted (55 patients) 10F silicone elastomer feeding tubes inserted nasally 85 cm. Tubes were placed with wire stylets. Tube positions were verified radiographically within 4 hr after insertions. Radiographs were repeated daily for 3 days or until duodenal intubation occurred. Successful duodenal intubations were achieved in 35 patients (57%) with weighted feeding tubes and in 37 patients (67%) with unweighted feeding tubes. This difference was not significant. Weighted nasoenteric feeding tubes offer no advantage over unweighted tubes in achieving duodenal intubations.  相似文献   
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Herniation of the glandular epithelium into the submucosa has been observed in 11 out of 27 cases of chronic ulcerative colitis. Glandular herniation was associated with thickening of the muscularis mucosae, with interruption of the muscularis mucosae by lymphoid follicles, and, in five of the 11 cases, with significant crowding of the glands of the mucosa. This study strongly suggests that sustained contraction of the muscularis mucosae, which has been shown by others to be a major feature of chronic ulcerative colitis, is the prime factor in the formation of downgrowths or herniations of the glandular epithelium into the submucosa. Comparison of the cases in which cancer developed with those where there was glandular herniation led to the conclusion that they are independent associations of chronic ulcerative colitis, and that glandular herniation plays no part in the development of dysplasia or cancer.  相似文献   
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NK cells acquire the ability to recognize MHC class I molecules during development. Studies with Qa-1(b) tetramers (Qa-1 tetramers) showed that nearly all NK1.1(+) cells from newborn C57BL/6 mice express Qa-1-binding receptors. Cytotoxic activity of these cells is fully inhibited by Qa-1 ligands on target cells. In contrast, neither receptors for H-2K(b) nor H-2D(b) were observed on NK1.1(+) cells from newborn mice. After birth, frequencies of Qa-1 tetramer(+)/ NK1.1(+) cells gradually decrease as the number of Ly49(+) /NK1.1(+) cells increases. Cell transfer studies showed that Qa-1 tetramer(+) cells from newborn mice do not lose expression of Qa-1 receptors, but that they further acquire expression of Ly49 molecules. Acquisition of Qa-1-binding receptors appears largely independent of host MHC class I molecules, as observed in studies using beta2-microglobulin-deficient (beta2m(-/-)) mice as well as K(b)/ D(b-/-) and K(b)/D(b)/beta2m(-/-) mice. The present results suggest that Qa-1-binding receptors play an important role in the specificity of developing NK cells, and suggest that these cells rely mainly on inhibitory receptors specific for non-classical MHC class I molecules to maintain self tolerance during the first weeks of life.  相似文献   
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