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排序方式: 共有474条查询结果,搜索用时 15 毫秒
91.
Rossella Briancesco Maurizio Semproni Rosa Paradiso Lucia Bonadonna 《Annals of microbiology》2014,64(2):735-740
Nontuberculous mycobacteria (NTM) are microorganisms commonly living in the environment. Nevertheless, most of them are opportunistic pathogens. To verify concentrations of NTM in some man-made habitats, analyses were performed on water and surface samples, and the data were correlated to the global microbiological quality of water. Most of the drinking water samples (98 %) complied with the microbial requirements established by the European Directive 98/83/EC on drinking water when Escherichia coli was considered. Low counts of heterotrophs were also obtained. NTM were isolated from 72 % of the analyzed samples. Tap water from private buildings, schools and hospitals provided positive results for NTM, with comparable densities ranging from 1 to 6?×102 CFU/L. NTM were also found in swimming pool water samples, with concentrations ranging from 29 to 3?×104 CFU/L, as well as in 70 % of the surface sample. The most frequently isolated species were Mycobacterium mucogenicum, M. intracellulare and M. terrae. These yields confirm that no correlation exists between the monitoring controls carried out by law and the occurrence of these bacteria that may represent a potential risk, especially for immunocompromised people and vulnerable groups. 相似文献
92.
Rossella Dorati Claudia Colonna Ida Genta Giovanna Bruni Livia Visai Bice Conti 《AAPS PharmSciTech》2014,15(1):75-82
Tridimensional scaffolds can promote bone regeneration as a framework supporting the migration of cells from the surrounding tissue into the damaged tissue and as delivery systems for the controlled or prolonged release of cells, genes, and growth factors. The goal of the work was to obtain an advanced medical device for bone regeneration through coating a decellularized and deproteinized bone matrix of bovine origin with a biodegradable, biocompatible polymer, to improve the cell engraftment on the bone graft. The coating protocol was studied and set up to obtain a continuous and homogeneous polylactide-co-glycolide (PLGA) coating on the deproteinized bone matrix Orthoss® block without occluding pores and decreasing the scaffold porosity. The PLGA-coated scaffolds were characterized for their morphology and porosity. The effects of PLGA polymer coating on cell viability were assessed with the 3-(4,5-dimethyl-2-thiazolyl)-2,5 diphenyl-2H-tetrazolium assay. The polymer solution concentration and the number of polymeric layers were the main variables affecting coating efficiency and porosity of the original decellularized bone matrix. The designed polymer coating protocol did not affect the trabecular structure of the original decellularized bone matrix. The PLGA-coated decellularized bone matrix maintained the structural features, and it improved the ability in stimulating fibroblasts attachment and proliferation. 相似文献
93.
Sahra Talamo Marco Peresani Matteo Romandini Rossella Duches Camille Jéquier Nicola Nannini Andreas Pastoors Andrea Picin Manuel Vaquero Gerd-Christian Weniger Jean-Jacques Hublin 《PloS one》2014,9(4)
In the northern Adriatic regions, which include the Venetian region and the Dalmatian coast, late Neanderthal settlements are recorded in few sites and even more ephemeral are remains of the Mid-Upper Palaeolithic occupations. A contribution to reconstruct the human presence during this time range has been produced from a recently investigated cave, Rio Secco, located in the northern Adriatic region at the foot of the Carnic Pre-Alps. Chronometric data make Rio Secco a key site in the context of recording occupation by late Neanderthals and regarding the diffusion of the Mid-Upper Palaeolithic culture in a particular district at the border of the alpine region. As for the Gravettian, its diffusion in Italy is a subject of on-going research and the aim of this paper is to provide new information on the timing of this process in Italy. In the southern end of the Peninsula the first occupation dates to around 28,000 14C BP, whereas our results on Gravettian layer range from 29,390 to 28,995 14C years BP. At the present state of knowledge, the emergence of the Gravettian in eastern Italy is contemporaneous with several sites in Central Europe and the chronological dates support the hypothesis that the Swabian Gravettian probably dispersed from eastern Austria. 相似文献
94.
Francesco Pallotti Giorgio Binelli Raffaella Fabbri Maria L. Valentino Rossella Vicenti Maria Macciocca Sabina Cevoli Agostino Baruzzi Salvatore DiMauro Valerio Carelli 《PloS one》2014,9(5)
Segregation of mutant mtDNA in human tissues and through the germline is debated, with no consensus about the nature and size of the bottleneck hypothesized to explain rapid generational shifts in mutant loads. We investigated two maternal lineages with an apparently different inheritance pattern of the same pathogenic mtDNA 3243A>G/tRNALeu(UUR) (MELAS) mutation. We collected blood cells, muscle biopsies, urinary epithelium and hair follicles from 20 individuals, as well as oocytes and an ovarian biopsy from one female mutation carrier, all belonging to the two maternal lineages to assess mutant mtDNA load, and calculated the theoretical germline bottleneck size (number of segregating units). We also evaluated “mother-to-offspring” segregations from the literature, for which heteroplasmy assessment was available in at least three siblings besides the proband. Our results showed that mutation load was prevalent in skeletal muscle and urinary epithelium, whereas in blood cells there was an inverse correlation with age, as previously reported. The histoenzymatic staining of the ovarian biopsy failed to show any cytochrome-c-oxidase defective oocyte. Analysis of four oocytes and one offspring from the same unaffected mother of the first family showed intermediate heteroplasmic mutant loads (10% to 75%), whereas very skewed loads of mutant mtDNA (0% or 81%) were detected in five offspring of another unaffected mother from the second family. Bottleneck size was 89 segregating units for the first mother and 84 for the second. This was remarkably close to 88, the number of “segregating units” in the “mother-to-offspring” segregations retrieved from literature. In conclusion, a wide range of mutant loads may be found in offspring tissues and oocytes, resulting from a similar theoretical bottleneck size. 相似文献
95.
Annarita Falanga Rossella Tarallo Thomas Carberry Massimiliano Galdiero Marcus Weck Stefania Galdiero 《PloS one》2014,9(11)
We have demonstrated that amide-based dendrimers functionalized with the membrane-interacting peptide gH625 derived from the herpes simplex virus type 1 (HSV-1) envelope glycoprotein H enter cells mainly through a non-active translocation mechanism. Herein, we investigate the interaction between the peptide-functionalized dendrimer and liposomes composed of PC/Chol using fluorescence spectroscopy, isothermal titration calorimetry, and surface plasmon resonance to get insights into the mechanism of internalization. The affinity for the membrane bilayer is very high and the interaction between the peptide-dendrimer and liposomes took place without evidence of pore formation. These results suggest that the presented peptidodendrimeric scaffold may be a promising material for efficient drug delivery. 相似文献
96.
Paola Maraschio Rossella Tupler Laura Barbierato Eleonora Dainotti Daniela Larizza Franca Bernardi Heidi Hoeller Angiolina Garau Luciano Tiepolo 《Human genetics》1996,97(3):375-381
We characterized by fluorescence in situ hybridization and Southern blotting 14 partial Xq monosomies, 11 due to terminal deletions and 3 secondary to X/autosome translocations. Three cases were mosaics with a XO cell line. In view of the possible role played by telomeres in chromosome segregation, we hypothesize a relationship between the loss of telomeric sequences in terminal deletions and the presence of 45,X cells. A correlation between phenotype and extent of deletion revealed that there is no correspondence between the size of the deletion and impairment of gonadal function. Turner stigmata are absent in patients without an XO cell line, when the breakpoint is distal to Xg24. A low birthweight is present whenever the breakpoint is at q22 or more proximal. 相似文献
97.
Valentina E. Di Mattei Letizia Carnelli Martina Mazzetti Martina Bernardi Rossella Di Pierro Alice Bergamini Giorgia Mangili Massimo Candiani Lucio Sarno 《PloS one》2016,11(4)
BackgroundGestational Trophoblastic Disease comprises a group of benign and malignant disorders that derive from the placenta. Using Leventhal’s Common-Sense Model as a theoretical framework, this paper examines illness perception in women who have been diagnosed with this disease.MethodsThirty-one women diagnosed with Gestational Trophoblastic Disease in a hospital in Italy were asked to complete the Illness Perception Questionnaire-Revised to measure the following: illness Identity, illness opinions and causes of Gestational Trophoblastic Disease.ResultsHigh mean scores were observed in the Emotional representations and Treatment control subscales. A significant difference emerged between hydatidiform mole patients and those with gestational trophoblastic neoplasia on the Identity subscale. A significant correlation emerged between “time since diagnosis” and the Treatment control subscale.DiscussionThis study is the first to investigate illness perception in Gestational Trophoblastic Disease. From a clinical perspective the results highlight the need for multidisciplinary support programs to promote a more realistic illness perception. 相似文献
98.
G. Simoni G. Gimelli Cristina Cuoco Lorenza Romitti G. Terzoli Silvana Guerneri Franca Rossella Luisa Pescetto Annalisa Pezzolo Simona Porta B. Brambati E. Porro M. Fraccaro 《Human genetics》1986,72(3):203-209
Summary Cytogenetic investigations for diagnostic purposes were performed on 1000 first trimester samples of chorionic villi (CVS) in two laboratories using similar techniques. Fetal karyotyping was the primary indication for CVS in 912 and maternal age was the major indication in 758 of them. The risk category previous child/fetus with chromosome abnormality included 74 diagnoses, while the category chromosome abnormality in one of the parents included 38 diagnoses. Sex determination was the primary indication for CVS in 53 pregnancies. The overall incidence of chromosomal abnormalities was 70, of which 47 were balanced and 23 unbalanced. The results are detailed for each of the risk categories and the incidence of abnormal karyotypes is given for each year of maternal age. In the maternal age of 35–37 years the incidence of unbalanced karyotypes was 2.9% and in the years 38 onwards it was 6.6%. The incidence of unbalanced karyotypes was about 4% when the sampling was made in the weeks 9 to 12 but six abnormal karyotypes were found among 39 CVS performed at the eight week of gestation. The 11 trisomies of the type not found at birth were clustered between the 8th and the 10th week of pregnancy. The technical problems encountered in this experience and the preliminary estimates of fetal loss are discussed. 相似文献
99.
Summary A marriage between two first cousins who have the same 2/7 balanced translocation is reported. The chromosome rearrangement was primarily detected in amniotic fluid cells cultured for prenatal chromosome analysis because of advanced maternal age. The translocation was also found in the couple's two normal children and in three other members of the family. The possible zygotic chromosome constitutions following 2:2 meiotic segregation in consanguineous parents with the same translocation are discussed. 相似文献
100.