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1.
Even if the relationships between nutrition and inflammatory bowel disease (IBD) remain underexplored, the current literature is providing, day by day, much more evidence on the effects of various diets in both prevention and treatment of such illnesses. Wrong dietary habits, together with other environmental factors such as pollution, breastfeeding, smoke, and/or antibiotics, are among the theoretical pathogenetic causes of IBD, whose multifactorial aetiology has been already confirmed. While some of these risk factors are potentially reversible, some others cannot be avoided, and efficient treatments become necessary to prevent IBD spread or recurrence. Furthermore, the drugs currently available for treatment of such disease provide low-to-no effect against the symptoms, making the illnesses still strongly disabling. Whether nutrition and specific diets will prove to effectively interrupt the course of IBD has still to be clarified and, in this sense, further research concerning the applications of such dietary interventions is still needed.  相似文献   
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The implantation of chondrocytes, seeded on matrices such as hyaluronic acid or collagen membranes, is a method that is being widely used for the treatment of chondral defects. The aim of the present study was to evaluate the distribution, viability and phenotype expression of the cells seeded on a collagen membrane just at the time of the implantation. Twelve patients who were suffering from articular cartilage lesions were treated by the MACI® procedure. The residual part of each membrane was tested by colorimetric assay (MTT) and histochemical and ultrastructural analyses were carried out. In all of the samples a large number of viable cells, quite homogenously distributed, was detected. The cells expressed the markers of the differentiated hyaline chondrocytes. These data reassure in that the MACI procedure provides a suitable engineered tissue for cartilage repair, in line with the clinical evidences emerging in the literature.  相似文献   
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Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open.  相似文献   
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Mydriasis in giant-cell arteritis   总被引:1,自引:0,他引:1  
A previously healthy 60-year-old woman developed headache, cervical pain, bilateral mydriasis (right greater than left), and bilateral conjunctival injection as the sole manifestations of acute giant-cell arteritis.  相似文献   
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Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
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The protean manifestations of a novel maternally inherited point mutation of the mitochondrial genome are reported. The proband showed isolated, spastic paraparesis. A brother, who had suffered from a multisystem progressive disorder, ultimately died of cardiomyopathy. Another brother is healthy. The proband's mother showed truncal ataxia, dysarthria, severe hearing loss, mental regression, ptosis, ophthalmoparesis, distal cyclones, and diabetes mellitus. A muscle biopsy performed in the proband failed to show the morphological abnormalities typical of mitochondrial disorders; the activities of respiratory chain complexes were normal. However, complex I and IV activities were low in the muscle homogenate of the affected mother and brother. Sequence analysis of mtDNA showed a heteroplasmic mutation of the tRNA(Ile) gene (G4284A). The mutation load was approximately 55%, 80%, and 90% in the muscle mtDNA of the proband, his mother, and his affected brother, respectively. Mutation was undetected in the healthy brother, as well as in 100 control samples. Several cybrid clones containing homoplasmic mutant mtDNA from the proband showed significant reductions of complex IV activity and maximum oxygen consumption rate, compared with homoplasmic wild-type clones derived from the same subject.  相似文献   
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