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91.
The aim of this study was to experiment with simple, low cost tests which are able to detect the presence of compounds and/or toxic substances in soil. Their genotoxic potential was evaluated using the Ames and Tradescantia Micronuclei tests. Qualitative and quantitative analyses were also performed to assess the presence of edaphic micro and macro fauna in soil samples collected from both the contaminated and adjacent areas. Our results show that these tests are a useful screening method to check for the presence of harmful, toxic substances affecting the quality of soil and the surrounding ecosystem.  相似文献   
92.
BACKGROUND AND AIMS: Vitamin D deficiency is a well-known risk for hip fracture, and vitamin D insufficiency is so frequent in the elderly that population-wide preventive intervention would be useful. The objective of the study was to evaluate the efficacy of vitamin D bolus on hip fracture incidence in elderly women. METHODS: All women aged > 65 years registered at Health District 20 of the Regione Veneto, Italy, were eligible for this quasi-experimental, prospective community intervention study. A vial containing 400,000 IU vitamin D2 (Ostelin 800, Teofarma, Italy) was offered for oral administration to all women in the winters of 2000-2001 and 2001-2002. The only exclusion criteria for treatment were age and gender, and the control group included women who did not participate in the Health District initiative. Analysis of hip fracture incidence was carried out for 4 years, from 1999 to 2002. Patients with incident hip fracture were identified as soon as they were admitted to one of the 3 hospitals of the health district and interviewed regarding their participation in the vitamin D preventive intervention program. In 120 of the women (age range 68-90 years), serum concentrations of 25-OH vitamin D were measured from October to June, both before and 1 and 4 months after vitamin D administration. RESULTS: 23,325 and 24,747 women received the vitamin D bolus during winters 2000-2001 and 2001-2002 respectively, i.e. 45-47% of eligible women. The proportion of women who accepted the bolus declined with advancing age, from 50-55% in women aged 60-70 years to 22-26% in those aged > 90 years. The two-year intervention on the community decreased the incidence of fracture by 10% (p = 0.050) in comparison with the previous two years. The age-adjusted risk reduction (RR) of hip fracture during 2001 and 2002 in women who had received vitamin D, with respect to women who had not, decreased by 17% (p = 0.056) and 25% (p = 0.005) respectively. The RR was considerably greater and statistically significant over both 2001 and 2002 in the cohort aged > 75 years. 25-OH vitamin D concentrations, in the subset of women in whom it was measured, rose significantly (p < 0.0001) by 9 ng/ml over 4 months after administration. CONCLUSION: Despite several obvious limitations due to its nature, this study sufficiently documents that yearly vitamin D bolus supplements, given as primary prevention to elderly Caucasian women, may decrease the incidence of hip fracture. For its probable safety and excellent feasibility and cost-effectiveness, this primary intervention has a great potential for generalisability.  相似文献   
93.
Children and adolescents with growth hormone (GH) deficiency (GHD) have reduced bone turnover and bone mass in comparison with normal individuals. GH replacement therapy stimulates bone turnover and improves bone mass during childhood and adolescence. At final height, patients with GHD treated with GH have normal mean values of bone mass, but some patients have reduced lumbar BMD (Z score <1) with an increased susceptibility to fractures. Children and adolescents with GHD have approximately a fourfold decreased fracture frequency during treatment in comparison with controls. The changes of bone mass during the transition to adulthood in patients with GHD who discontinued GH treatment after final height are not defined. An increase of lumbar BMD after final height has been reported until 2 years after discontinuation of GH treatment; this could be the result of a spontaneous progression towards peak bone mass or of a persisting effect of GH treatment on bone mass accumulation. GH has an important role in the accrual of bone mass during childhood and adolescence, but the impact of GHD on bone mass during the transiton to adulthood is unknown.  相似文献   
94.
The murine mammary adenocarcinoma cell line TS/A is a highly malignant MHC class II-negative tumor. We show that transfection of TS/A cells with the MHC class II transactivator CIITA renders them MHC class II-positive and highly immunogenic in vivo. These cells were fully rejected by 51% of syngeneic recipients and had a significantly lower growth rate in the remaining 49% of animals. This directly correlated to the amount of MHC class II molecules expressed in the transfected tumor. Tumor rejecting animals were protected against rechallenge with the parental TS/A tumor. The rejection required CD4(+) and CD8(+) T cells. CD4(+) T cells were fundamental in the priming phase of the antitumor response. CTL-specific for a peptide of the envelope gp70 of an endogenous ecotropic retrovirus were identified and explained the specificity of the effector mechanism of rejection against the TS/A and the antigenically related C26 carcinoma cells but not against the unrelated gp70-negative syngeneic fibrosarcoma F1F cells. This is the first example of successful tumor vaccination by genetic transfer of CIITA. These results open the way to a possible use of CIITA for increasing both the inducing and the effector phase of the antitumor immune response.  相似文献   
95.
OBJECTIVE: A role of female hormones, including oral contraceptives, has been suggested in the etiology of focal nodular hyperplasia of the liver. There is, however, no epidemiologic quantification of this relationship. STUDY DESIGN: A hospital-based case-control study was conducted in Italy of 23 women with histologically confirmed focal nodular hyperplasia of the liver and 94 controls in the hospital for acute diseases. Odds ratios (ORs) were computed by use of multiple logistic regression models. RESULTS: Focal nodular hyperplasia was not associated with menstrual and reproductive factors. Ever oral contraceptive use was reported by 83% of cases and 59% of controls. The multivariate OR was 2.8 (95% confidence interval [CI], 0.8-9.4) for ever use, and 4.5 (95% CI, 1.2-16.9) for use > or = 3 years. The trend in risk with duration was statistically significant. CONCLUSIONS: This study confirms previous clinical observations, and provides a quantitative estimate of the association between use of oral contraceptives and focal nodular hyperplasia of the liver.  相似文献   
96.
97.
In the early eighties, in the US the advantages (reduced costs, no hospitalisation trauma in children, no immobilization syndrome in elderly, reduction of nosocomial and acquired infections by multi-resistant organisms) of OPAT were identified and suitable therapeutic programs were established. Following the US experience, other countries set up their own OPAT programs which vary considerably from country to country because of different ways in which infections are managed in different parts of the world and because of different reimbursement systems. In order to understand the ways of managing OPAT and its results, a National OPAT Registry was set up in 1999 in Italy belonging to a wider International OPAT database, which collects data also from USA, Canada, Spain, Uruguay and Argentina. Up to now 396 patients and as many antibiotic courses have been included in the National Registry by eight different centres. The analysis of data permits to get information about the criteria of patient's selection, treatment (route of administration, site of care, choice of antibiotic, dosage and duration), outcomes and possible side-effects. Italian results offer a quite peculiar picture of OPAT in this country when comparing data with those of other countries. In contrast with other countries where soft tissue infections and osteomyelitis are the most frequent diagnoses for including patients in OPAT programmes, in Italy pneumonia and bronchitis are the top two amenable infections. Ceftriaxone, Teicoplanin and Amikacin are absolutely the top three antibiotics selected for OPAT in Italy which confirm that a single daily dose regimen represents a great advantage in terms of compliance. Finally, a large percentage of antibiotic courses (50%) are carried out by using the i.m. administration route, which is very unusual in other countries. OPAT Registry is still ongoing and it will give us more detailed information in the future about the management of infections in the outpatient setting, but it already permits to define an actual picture of OPAT in our country and/or to compare and correlate data and information from different countries.  相似文献   
98.
We analyzed the epitopes and the molecular forms of Tat recognized by the antibodies raised by Tat-toxoid vaccination in both healthy and HIV-infected volunteers. Tat-toxoid-vaccinated healthy volunteer sera reacted predominantly with peptides covering amino acids 1 through 24 and 46 through 60, corresponding to the N-terminus and basic domains of Tat. In contrast, whereas all sera from vaccinated HIV-1-positive patients reacted with the N-terminus and (with a single exception) with the basic domain, most of these sera also recognized peptides encompassing distinct domains of Tat, particularly the C-terminus (79-86). The sera of vaccinated individuals recognized both monomeric and oligomeric forms of Tat 1 through 86 or of Tat 1 through 101 and also blocked the ability of cell-released extracellular Tat to transactivate the HIV-1 LTR promoter. Synthetic Tat preincubated with sera from vaccinated individuals lost its functional activity as well. This is probably because of its inability to enter the cells as a result of immune complex formation with anti-Tat IgG. These data demonstrate that Tat-toxoid vaccination induces an efficient antibody response blocking the functional activity of Tat.  相似文献   
99.
100.
We analyzed the potential role of pizza on cancer risk, using data from an integrated network of case-control studies conducted in Italy between 1991 and 2000. Cancer sites were: oral cavity and pharynx (598 cases), esophagus (304 cases), larynx (460 cases), colon (1,225 cases) and rectum (728 cases). Controls were 4,999 patients admitted for acute, non-neoplastic conditions to the same hospital network as cases. Odds ratios for regular pizza consumers were 0.66 (95% confidence interval, CI = 0.47-0.93) for oral and pharyngeal cancer, 0.41 (95% CI = 0.25-0.69) for oesophageal, 0.82 (95% CI = 0.56-1.19) for laryngeal, 0.74 (95% CI = 0.61-0.89) for colon and 0.93 (95% CI = 0.75-1.17) for rectal cancer. Pizza appears therefore to be a favorable indicator of risk for digestive tract neoplasms in this population.  相似文献   
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