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91.
Microbiological contamination of chicken meat depends on the conditions under which the animals are reared, slaughtered and processed. The aim of this study was to determine the influence of farm origin and processing stages at slaughterhouse on the microbial safety and quality of chicken. Samples of chicken carcasses from three different farms were taken from a slaughterhouse. Mesophiles, Escherichia coli, coagulase positive Staphylococcci counts, presence of Listeria monocytogenes,Campylobacter and Salmonella were determined at five sampling points: after defeathering, after evisceration, after washing, after chilling and after cutting. Chilling reduced log numbers of mesophiles, coagulase positive Staphylococci and E. coli by 0.85, 1.52 and 2.2 log units, respectively. Salmonella was not detected after chilling. High prevalence of Campylobacter spp was observed at all the stages ranging between 84% and 100%. L. monocytogenes was not detected in chicken carcasses after defeathering. However, it was detected after evisceration and after washing and chilling. The most critical stage for Lmonocytogenes contamination was the portioning operation, the prevalence in breast and legs being 88% and 84%, respectively.  相似文献   
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CD22 (Siglec-2) is a B-cell surface inhibitory protein capable of selectively recognising sialylated glycans, thus dampening autoimmune responses against self-antigens. Here we have characterised the dynamic recognition of complex-type N-glycans by human CD22 by means of orthogonal approaches including NMR spectroscopy, computational methods and biophysical assays. We provide new molecular insights into the binding mode of sialoglycans in complex with h-CD22, highlighting the role of the sialic acid galactose moieties in the recognition process, elucidating the conformational behaviour of complex-type N-glycans bound to Siglec-2 and dissecting the formation of CD22 homo-oligomers on the B-cell surface. Our results could enable the development of additional therapeutics capable of modulating the activity of h-CD22 in autoimmune diseases and malignancies derived from B-cells.  相似文献   
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A study of the phosphorescence mechanisms in polycrystalline diamond films was carried out through their thermoluminescent (TL) vanishing glow response. The polycrystalline diamond films phosphoresced when kept at room or higher temperatures after being excited with a UV light source. The observed behaviour of shallow and deep traps during the phosphorescence process can be explained with a simple time-dependent model. The diamond film phosphorescence was induced by exciting with a UV light source of 4 W and 254 nm wavelength. The TL vanishing glow curves were integrated from room temperature to 350°C at a linear heating rate of 10°C s-1 in a N2 atmosphere. The optical response of the diamond films was studied by means of its luminescence spectra, showing a broad emission band centered around 500 nm.  相似文献   
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OBJECTIVE: The influence of psychogenic factors on voiding generally manifests as an irritative syndrome and rarely in the form of acute or chronic urinary retention. The diagnosis and treatment of this uncommon urological pathology are reviewed and our experience is presented. METHODS: We conducted a retrospective study on 5 patients with psychogenic urinary retention (3 males and 2 females), aged 20 to 28 years (mean age 23.4), that had been treated at our urological services over the last 6 years. Three patients (2 males and 1 female) had a history of depression, one patient had a somatic form of disorder (mimicking) and one patient was diagnosed as having schizophrenia one year after he had presented with urinary retention. The physical and neurological examinations were normal in all 5 patients and the radiological evaluation was normal in all but one patient who had bilateral hydronephrosis. The pressure/flow test disclosed absence of detrusor muscle contraction in all 5 patients; 3 had incomplete voiding by abdominal pressure and had more than 500 ml residual urine. All patients received psychiatric therapy, and intermittent catheterization and urinary rehabilitation until residual urine less than 100 ml was achieved. CONCLUSIONS: The importance of the urodynamic study in the diagnosis of this condition is underscored. Definitive diagnosis can only be established after discarding other pathologies. The initial treatment must always be conservative; irreversible surgical procedures must not be performed. Treatment is by intermittent catheterization, urinary rehabilitation and supportive psychiatric therapy.  相似文献   
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