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排序方式: 共有1516条查询结果,搜索用时 15 毫秒
1.
R. Perniola M. L. Faneschi E. Manso M. Pizzolante A. Rizzo A. Sticchi Damiani R. Longo 《European journal of clinical microbiology & infectious diseases》2006,25(3):193-196
Reported here are the features of a Rhodotorula mucilaginosa outbreak that occurred in a neonatal intensive care unit. Over a period of 19 days, clinical and laboratory signs of sepsis appeared in four premature infants carrying indwelling vascular catheters. After bloodstream infection with R. mucilaginosa was ascertained, the patients underwent amphotericin B therapy and recovered completely. In a retrospective case-control study, the variables displaying a statistical difference between case and control-group neonates were birth weight, gestational age, duration of parenteral nutrition, duration of antibiotic therapy and prophylactic administration of fluconazole. To our knowledge, this is the first reported outbreak caused by yeasts of the Rhodotorula genus. 相似文献
2.
Roberto Perniola Giuseppe Tamborrino Santo Marsigliante Corrado De Rinaldis 《Journal of oral pathology & medicine》1998,27(6):278-282
The features of enamel hypoplasia in a small group of patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) are described. Using a recently developed method, the authors evaluated quantitatively the amount of defect in each tooth by measuring the width of the hypoplastic lesions and dividing the value by the crown height. They then assessed the degree of damage in each tooth type (from central incisors to second premolars) and patient. Canines were the most severely affected among maxillary and mandibular teeth, but all tooth types were involved. Analysing both the differences between patients and their age at the beginning of the defect, the authors observe that hypoparathyroidism is not responsible for the onset of enamel hypoplasia in APECED, although it may contribute to the damage. 相似文献
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4.
BACKGROUND: Many advances have been made in the sensitivity of assays for hepatitis C virus antibodies (HCV-Ab). Nevertheless, polymerase chain reaction (PCR) is still the best method to establish if infection has become chronic. In this study we utilised third-generation assays for HCV-Ab in a four-year follow-up to determine the trend in antibody levels in currently and past infected patients. METHODS: Seventy-two multitransfused subjects were enrolled. All the patients were reactive at the first test with third-generation screening and confirmatory assays (ELISA-3 and RIBA-3) for HCV-Ab. They were subsequently retested in a follow-up ranging from 41 to 47 months. Viraemia was investigated with a standardised PCR kit; negative samples were reevaluated with nested PCR. Differences in antibody trend were calculated with the Wilcoxon signed-rank test. RESULTS: No statistical variation in antibody titre was found in the 41 HCV-RNA positive patients, although some of these showed a decrease in anti-c100p level. In contrast, anti-c22p, anti-c33c and anti-c100p levels decreased significantly in the 19 past infected patients. Twelve patients were HCV-RNA negative or intermittently positive with commercial PCR test, and consistently or intermittently positive in nested PCR: in these patients, antibody trend varied. CONCLUSIONS: Although resolving hepatitis is associated with a decrease in antibody titre, the trend should be observed for a long period to distinguish between chronic and past infection. However, the evaluation in a single patient can be unreliable. Since a doubtful response for HCV-RNA is in some cases obtained, further improvements in the diagnosis of chronic HCV infection are needed. 相似文献
5.
Aldo Becciolini Manuela Balzi Paola Faraoni Elena Tisti Giorgia Zappoli Thyrion Valentino Giach Luca Bandettini Christopher S. Potten 《Acta oncologica (Stockholm, Sweden)》1998,37(1):65-71
Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns 1) with a high concentration in the bottom fifth of the crypt and 2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt. 相似文献
6.
BACKGROUND AND PURPOSE: To appraise the potential benefit of a conformal technique with non-coplanar fields to minimise lung irradiation in the radiation treatment of breast. PATIENTS AND METHODS: A comparative study was carried out at planning level for six patients selected for their inadequate sparing of healthy lung tissue with the reference tangential technique. Plans were designed for the conventional tangential technique, for an alternative conformal approach with three beams and for the newly proposed technique with two non-coplanar beams. RESULTS: In average for the new technique compared to the reference, mean lung dose dropped from approximately 16 to 10.5 Gy, V(20 Gy) from 29.5 to 18.2% and the dose delivered to 1/3 (1/4) of the lung volume dropped from 28.5% (67.3%) to 8.7% (13.4%). For PTV, the volume receiving at least 90% of the prescribed dose resulted 97.4% for the new and 97.3% for the reference. Conformity index improved significantly from 2.58 for the reference to 1.84 for the new technique. CONCLUSIONS: For a subgroup population of breast cancer patients, where conventional techniques failed to achieve high conformal avoidance, a treatment modality with non-coplanar beams was developed and clinically tested for six patients. It resulted dosimetrically adequate, particularly when the risk of toxicity is relevant. 相似文献
7.
Enrico Soldati Flavy Roseren Daphne Guenoun Lucia Mancini Emilio Catelli Silvia Prati Giorgia Sciutto Jerome Vicente Stefano Iotti David Bendahan Emil Malucelli Martine Pithioux 《Materials》2022,15(22)
Although multiple structural, mechanical, and molecular factors are definitely involved in osteoporosis, the assessment of subregional bone mineral density remains the most commonly used diagnostic index. In this study, we characterized bone quality in the femoral neck of one osteoporotic patients as compared to an age-matched control subject, and so used a multiscale and multimodal approach including X-ray computed microtomography at different spatial resolutions (pixel size: 51.0, 4.95 and 0.9 µm), microindentation and Fourier transform infrared spectroscopy. Our results showed abnormalities in the osteocytes lacunae volume (358.08 ± 165.00 for the osteoporotic sample vs. 287.10 ± 160.00 for the control), whereas a statistical difference was found neither for shape nor for density. The osteoporotic femoral head and great trochanter reported reduced elastic modulus (Es) and hardness (H) compared to the control reference (−48% (p < 0.0001) and −34% (p < 0.0001), respectively for Es and H in the femoral head and −29% (p < 0.01) and −22% (p < 0.05), respectively for Es and H in the great trochanter), whereas the corresponding values in the femoral neck were in the same range. The spectral analysis could distinguish neither subregional differences in the osteoporotic sample nor between the osteoporotic and healthy samples. Although, infrared spectroscopic measurements were comparable among subregions, and so regardless of the bone osteoporotic status, the trabecular mechanical properties were comparable only in the femoral neck. These results illustrate that bone remodeling in osteoporosis is a non-uniform process with different rates in different bone anatomical regions, hence showing the interest of a clear analysis of the bone microarchitecture in the case of patients’ osteoporotic evaluation. 相似文献
8.
Smell strongly contributes to food choice and its hedonistic evaluation. A reduction or loss of smell has been related to malnutrition problems, resulting in excessive weight loss or gain. Voltage-gated potassium channels Kv1.3 are widely expressed in the olfactory bulb, and contribute mainly to the value of the resting membrane potential and to the frequency of action potentials. Mutations in the Kv1.3 gene are associated with alterations in glycemic homeostasis and olfactory sensitivity. We evaluated the olfactory performance in 102 healthy subjects and its association with BMI and polymorphism in the human Kv1.3 gene. Olfactory performance, based on the olfactory threshold, discrimination and identification scores and their summed score (TDI), was measured using the “Sniffin’ Sticks” test. Subjects were genotyped for the rs2821557 polymorphism of the Kv1.3 gene, whose major allele T was associated with a super-smeller phenotype, lower plasma glucose levels and resistance to diet-induced obesity as compared with the minor allele C. Based on the Kv1.3 genotype, the TDI and I olfactory scores obtained by the subjects were the following: TT > TC > CC. Subjects who were TT homozygous or heterozygous exhibited lower BMIs and reached higher olfactory scores than those with the CC genotype. The results were sex-dependent: heterozygous females performed better than heterozygous males. These findings show an inverse relationship between olfactory function and BMI, and a significant effect of the Kv1.3 genotypes on the olfactory functions and on the BMIs of the subjects. Finally, they suggest that the sex-related differences in the olfactory function can be partially ascribed to the Kv1.3 gene’s polymorphism. 相似文献
9.
Luisa Carbognin Cristina Accetta Danilo Di Giorgio Paola Fuso Margherita Muratore Giordana Tiberi Francesco Pavese Tatiana DAngelo Alessandra Fabi Diana Giannarelli Alba Di Leone Stefano Magno Giorgia Garganese Alejandro Martin Sanchez Daniela Andreina Terribile Gianluca Franceschini Riccardo Masetti Giovanni Scambia Ida Paris 《Current oncology (Toronto, Ont.)》2022,29(10):7218
The prevention of chemotherapy-induced alopecia still represents an urgent need for every day clinical practice. In this regard, this prospective single-center study included breast cancer (BC) patients who underwent a scalp cooling device (Dignicap®) during (neo)adjuvant chemotherapy with the aim to evaluate the efficacy and safety of this device in preventing alopecia. One hundred and seventy-eight patients (median age 43 years) were enrolled. The chemotherapy regimen included anthracycline and taxane-based chemotherapy (68.1%), docetaxel and cyclophosphamide (25.8%), anthracycline and taxane-based plus carboplatin (3.9%), and paclitaxel alone (2.2%). In 25.3% of cases, a dose dense schedule was used. Overall, the success rate was 68.0%: 100% in paclitaxel alone, 87.0% in docetaxel-cyclophosphamide, 59.5% in anthracycline and taxane, and 71.4% in the sequential regimen plus carboplatin group (anthracycline and taxane-based chemotherapy versus taxane-based chemotherapy, p ≤ 001. No difference in terms of hair preservation between dose-dense or standard schedule was found (p = 0.557). Early discontinuation of the scalp cooling was observed in 50 patients (28.1%). Although 138 patients (77.5%) experienced adverse events, 70.2% of patients were satisfied with this device. In conclusion, this large prospective study confirmed the helpful effect of the scalp cooling system in preventing alopecia in BC patients also undergoing sequential anthracyclines and taxane-based chemotherapy. 相似文献
10.
Mauro DiNuzzo Daniele Mascali Giorgia Bussu Marta Moraschi Maria Guidi Emiliano Macaluso Silvia Mangia Federico Giove 《Human brain mapping》2022,43(15):4529
Visuospatial attention is strongly lateralized, with the right hemisphere commonly exhibiting stronger activation and connectivity patterns than the left hemisphere during attentive processes. However, whether such asymmetry influences inter‐hemispheric information transfer and behavioral performance is not known. Here we used a region of interest (ROI) and network‐based approach to determine steady‐state fMRI functional connectivity (FC) in the whole cerebral cortex during a leftward/rightward covert visuospatial attention task. We found that the global FC topology between either ROIs or networks was independent on the attended side. The side of attention significantly modulated FC strength between brain networks, with leftward attention primarily involving the connections of the right visual network with dorsal and ventral attention networks in both the left and right hemisphere. High hemispheric functional segregation significantly correlated with faster target detection response times (i.e., better performance). Our findings suggest that the dominance of the right hemisphere in visuospatial attention is associated with an hemispheric functional segregation that is beneficial for behavioral performance. 相似文献