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C M Kyaw C R De Araujo M R Lima E G S Gondim M M Brígido L G Giugliano 《Infection, genetics and evolution》2003,3(2):111-117
Diffusely adhering Escherichia coli (E. coli) strains (DAEC) represent a potential cause of diarrhoea in infants, and the detection of type three secretion system (TTSS) genes in DAEC would substantiate their pathogenic nature. In this work, four isolates of DAEC, recovered from stools of diarrhoeic children, were analysed by PCR, in order to detect the presence of TTSS genes. Primers targeted to the escC, escJ, escN and escV, some of the most conserved TTSS genes in enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC), were used in order to verify the occurrence of homologous genes in our DAEC isolates. By this approach, we were able to characterise DNA fragments corresponding to putative escJ and escN genes in all DAEC isolates. Furthermore, DNA fragments homologous to the escC and escV genes were also amplified from all isolates. Besides the similarity found among the DAEC esc homologues with EPEC and EHEC esc genes, the nucleotide sequence analysis of the flanking regions of the amplified DNA fragments suggests that the putative DAEC esc genes are organised in the same manner as observed in EPEC and in EHEC strains. The results described here provide strong evidence for the presence of a TTSS in the DAEC strains analysed, implicating a pathogenic nature of these isolates. 相似文献
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Paracoccidioidomycosis of the central nervous system presents either as meningeal or pseudotumoral lesions. Although occurring more frequently in the brain and meninges, they can occasionally involve the spinal cord. A case of paracoccidioidomycosis in the cervical spinal cord is reported in this paper. Difficulties in establishing the etiologic diagnosis, the importance of radiologic examination of the thorax, and the treatment of the patient are commented. In an extensive review of the literature on the subject, only three other cases have been found, which are also discussed. 相似文献
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Vitamin K in colostrum and mature human milk over the lactation period--a cross-sectional study 总被引:1,自引:0,他引:1
L M Canfield J M Hopkinson A F Lima B Silva C Garza 《The American journal of clinical nutrition》1991,53(3):730-735
Vitamin K was quantitated in the milk of four groups of 15 mothers from 1 d to 6 mo postpartum in a cross-sectional study. Concentrations were 7.52 +/- 5.90 and 6.36 +/- 5.32 nmol/L (3.39 +/- 2.66 and 2.87 +/- 2.40 micrograms/L) in colostrum and mature milk, respectively. Differences between colostrum and mature milk or among samples of mature milk collected at 1, 3, and 6 mo were not statistically significant. Because of significantly increased volumes of milk over the lactation period, approximately twice as much vitamin K was delivered in mature milk as in colostrum. Within normal ranges, concentrations of vitamin K in milk were not predicted by dietary intake of vegetables or fat. Vitamin K was correlated with fat in colostrum and was localized in the lipid core of the milk fat globule but was not associated with membranes. Vitamin K in human milk is insufficient to meet recommended intakes for infants aged less than 6 mo. Population and clinical studies are needed to assess the vitamin K status of exclusively breast-fed infants and to evaluate current recommendations. 相似文献
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Jose M. Fernández-Cebrián Peter Vorwald Kuborn Mar Pardo de Lama Alfonso Sanjuanbenito Dehesa Manuel Nevado Santos Pedro A. Pacheco Martínez Beatriz Fernández-Escudero 《Clinical & translational oncology》2005,7(3):101-109
Colorectal cancer is one of the best studied of all malignant diseases interms of genetics and/or molecular prognostic factors. These factors, and relationships with prognosis, may have important implications especially in the design of surgical and adjuvant chemo-radiotherapy options. However, the true prognostic significance of all known factors has yet to be realised. We have reviewed the literature with specific focus on the role of molecular markers involved in prognosis and the prediction of response to adjuvant treatment. 相似文献
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Vivian E. von Gruenigen M.D. Joseph T. Santoso M.D. Robert L. Coleman M.D. Carolyn Y. Muller M.D. David Scott Miller M.D. J.Michael Mathis Ph.D. 《Gynecologic oncology》1998,69(3):197-204
Objectives.To test the safety, efficacy, and toxicity of gene therapy using wild-type p53-expressing adenovirus (Ad-CMV-p53) in a nude mouse model with intraperitoneal (ip) 2774 human ovarian cancer cell line that contains a p53 mutation.Study design.An initial study of adenovirus tolerance was determined in nude mice by a single ip injection of increasing doses of Ad-CMV-p53. Nude mice were implanted with an LD100dose of 1 × 107cells. To study the efficacy and specificity of Ad-CMV-p53 treatment, the mice received treatment with different adenovirus constructs. One group received Ad-CMV-p53 and another group received a control adenovirus construct, Ad-CMV-βgal. To study the treatment response to Ad-CMV-p53, the mice were divided into groups and received various treatment schedules of 1 × 108pfu of Ad-CMV-p53.Results.The mice tolerated Ad-CMV-p53 without adverse effects at doses of 1 × 108pfu. The response to Ad-CMV-p53 showed significant survival duration in each dose regimen, with a survival time greater than that of untreated animals (P= 0.0173). However, no statistically significant survival advantage was observed between Ad-CMV-p53- and Ad-CMV-βgal-treated mice.Conclusions.These studies show that at the adenovirus dose and administration regimen used, there is effective but not specific 2774 tumor growth inhibitionin vivo.Efficient introduction of biologically active genes into tumor cells would greatly facilitate cancer therapy. Thus, although promising, these results caution that much effort will be required to realize the potential for clinical application of adenovirus-based ovarian cancer gene therapy. 相似文献
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BACKGROUND: Patient education is integral part of any diabetes therapy in Germany, but elderly patients are not able to follow the variety of topics comprising standard treatment and teaching programmes (TTP), primarily due to impaired neuropsychological function. This leads to deficits in diabetes knowledge and hindered ability for diabetes self-management. AIM: To evaluate structured TTP for geriatric patients with impaired cognitive function. PATIENTS AND METHODS: A neuropsychological examination was performed on all patients over 54 years [n=102, age 68.6 +/- 8.7 years, diabetes duration 10.3 (0.03-35.4) years, HbA1c 10.3 +/- 1.7% (HPLC, Diamat, NR 4.5-6.3%), cognitive function 87.7 +/- 12.3 IQ points] who took part in TTP for insulin therapy. Patients with impaired cognitive function participated either in the standard TTP of Berger [n = 35, age 67.6 +/- 8.9 years, diabetes duration 9.9 (0.04-35.4) years, HbA1c 10.3 +/- 2.0%] or in the specialized structured geriatric DICOF-TTP [n=33, age 70.4 +/- 8.2 years, diabetes duration 10.4 (0.03-24.9) years, HbA1c 10.7 +/- 1.8%]. RESULTS: After TTP there were no differences in knowledge and ability for diabetes self-management (standard/DICOF: knowledge 11.0 +/- 2.6 vs. 12.2 +/- 2.7 points, P = 0.11; handling 14.9 +/- 3.3 vs. 15.9 +/- 2.5 points, P = 0.18). However, patients who took part in the DICOF programme showed better scores in satisfaction with the education programme [standard/DICOF 44.7 (31-57) vs. 52.5 (45-59) points, P < 0.001]. Six months later the DICOF participants showed better results regarding diabetes self-management (standard/DICOF: handling 12.5 +/- 4.1 vs. 15.9 +/- 3.1 points, P = 0.001). Both groups showed HbA1c decrease (8.3 +/- 1.4 vs. 8.5 +/- 1.3%, P=0.62) and similar incidence of acute complications. CONCLUSIONS: Elderly patients with impaired cognitive function should take part in specialized structured TTP. This leads to both better satisfaction with the education programme and an improved ability for diabetes self-management. 相似文献
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