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Introduction:Most of the molybdenum (Mo) is used in metallurgical applications, the tetrathiomolybdate form is an experimental chelating agent for Wilson’s disease. Human data of acute Mo exposure are lacking and, no report of no-observed-adverse-effect level (NOAEL) has been described until now.Case study:We report a case of acute occupational exposure to molybdenum, with the related plasma and urine molybdenum concentrations, caused by an accidental ingestion of a sip of an anti-corrosion liquid for metal containing sodium molybdate. Our purpose was to evaluate potential systemic toxicity of molybdenum and to evaluate the dose-response/dose-effect relationship. We estimated the amount of ingested molybdenum to make a mg/kg relationship and performed repeated urine and plasma molybdenum determinations. The patient was hospitalized for three days to monitor possible development of acute symptoms/biochemical alterations.Discussion:We estimated the amount of the sip around 50 ml, with an estimation of a total of 5 gr of sodium molybdate that, for the patient bodyweight of 80 kg, would mean 62,5 mg/kg of ingested Mo. Blood and urine samples collected 2 hours after ingestion showed 50 mcg/L (reference range: 0.43 – 1.8 mcg/L) and 630 mcg/L (refence range: up to 116 mcg/L) of Mo respectively, confirming acute exposure. The patients remained asymptomatic confirming that an estimated oral dose of Mo of 62.5 mg/kg was not associated with adverse effects.Conclusions:Our value, being extrapolated by a single case, will require further confirmations from other studies to allow a full evaluation of a NOAEL. Nevertheless, it does not preclude its use in evaluating the probable absence of adverse effect in the context of acute Mo exposure.  相似文献   
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This paper presents the results of an experimental investigation which was carried out with the purpose of assessing the performance-related properties of an emulsion-based cold-recycled mixture to be employed as a sustainable solution for the surface finishing of unpaved rural roads. This mixture contained significant quantities of recycled components (reclaimed asphalt and mineral sludge), and its composition was fine-tuned by following an innovative mix design procedure. Properties of these mixtures were studied by means of laboratory tests which considered key parameters, such as flowability, indirect tensile stiffness modulus, indirect tensile strength, moisture susceptibility and resistance to permanent deformation. It was found that, by means of the proposed mix design procedure, optimal dosages of the recycled components can be identified, thereby ensuring the achievement of the desired properties in terms of high workability and adequate stiffness and strength.  相似文献   
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Piedmont is a region in northwestern Italy counting 4.2 million inhabitants. The purpose of our study was to update data on incidence and outcomes of hip fractures (HF) in our region to present days. The data of all patients affected by HF in 2003 in Piedmont (total: 5,386 patients) were analyzed, determining the incidence of HF, mean age, sex, fracture pattern and treatment adopted. Additionally, 564 patients underwent a questionnaire on comorbidities, complications, functional outcome and survivorship. Overall incidence of HF was 126.13/100,000 inhabitants-year. Mean hospitalization was 13.67 days. Mean time to surgery was 2.67 days. Survivorship was 94% at 3-month, 71.32% at 1-year and 60.21% at 3-year follow-up. These up-to-date data on HF in our region are in accordance with the international literature and could prove useful for Orthopaedic and Trauma surgeons for giving information to patients and their relatives.  相似文献   
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Purpose  

Successful outcomes for an athlete usually consist of returning to their sport. The Subjective Patient Outcome for Return to Sports (SPORTS) score has been recently proposed as an easy to use score for evaluating an athlete’s ability to return to their sport. The aim of this study was to test the reliability and validity of the SPORTS score in athletes 5–10 years after anterior cruciate ligament reconstruction.  相似文献   
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ObjectiveThe aim of the present study was to evaluate whether vitamin D status is related to blood pressure (BP) in adults.MethodsWe evaluated the relationship between vitamin D status, intact parathyroid hormone (iPTH) and BP in 332 adults. Anthropometric measurements, BP, and a fasting blood sample was obtained. Participants were stratified into the following BP categories: 1) normal BP; 2) high BP; 3) normal BP through medication. Vitamin D insufficiency was defined as 25-hydroxvitamin D ≤ 75 nmol/L; high iPTH as > 65 pg/mL. The relationships between vitamin D status, iPTH and BP were adjusted for body mass index, waist circumference, blood lipids, physical activity, and sunscreen use.ResultsNo differences in prevalences of vitamin D insufficiency and high iPTH were observed among BP groups. No significant association was observed between BP and vitamin D status. Positive correlations were observed between iPTH and systolic BP (r = 0.168; P = 0.002) and between iPTH and diastolic BP (r = 0.168; P = 0.002). iPTH remained correlated with BP even with adjustments.ConclusionsThe present study contributes to the understanding of calcemic hormones and BP regulation.  相似文献   
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The possibility of using quantitative ultrasound (QUS) in monitoring the response to antiresorptive drugs has yet to be defined. The aim of the present study was to evaluate whether heel ultrasonography, considering its characteristics of long-term precision, is able to monitor osteoporotic patients treated with alendronate. We studied 150 postmenopausal osteoporotic women (age 59.6 ± 5.3 years) treated with alendronate and calcium (n= 74) or with calcium alone (n= 76) for 4 years. At baseline and after 12, 24, 36 and 48 months, we measured bone mineral density (BMD) at the lumbar spine by dual-energy X-ray absorptiometry (DXA, Hologic 4500), and speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness at the calcaneus by Achilles plus. Moreover, the longitudinal precision of QUS parameters was assessed by measuring 10 subjects once a month for 1 year and, on the basis of the coefficients of variation we obtained, we calculated the Least Significant Change between two measurements. In the alendronate-treated patients, at year 1, BMD increased by 4.2%, SOS by 0.4%, BUA by 1.1% and Stiffness by 3.2%; at year 2, BMD increased by 5.0%, SOS by 0.7%, BUA by 1.4% and Stiffness by 5.7%. At year 3, BMD increased by 6.2%, SOS by 0.9%, BUA by 1.8% and Stiffness by 7.6%. At the end of the study period, BMD increased by 7.6%, SOS by 1.2%, BUA by 1.9% and Stiffness by 9.0%. The minimal significant difference between two measurements was 0.8% for SOS, 5.6% for BUA and 5.0% for Stiffness. Among the QUS parameters, Stiffness showed the greatest total treatment effect and a longitudinal sensitivity which was only slightly lower than BMD. The MTI, which represents the period between scans required to show that a ‘true’ change has occurred, was 1.8, 2.7, 11.9 and 2.2 years for BMD, SOS, BUA and Stiffness respectively. Therefore, although the spinal BMD remains the optimal method, QUS at the heel, and in particular Stiffness, seems to be a sensitive tool for monitoring the response to alendronate. Received: 30 August 2001 / Accepted: 29 November 2001  相似文献   
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Background

After a brain biopsy, the genetic analysis can fail because of insufficient material, extensive tumor necrosis, and formalin fixation under conditions that adversely affected the quality of the DNA or because the assay result was indeterminant. The freezing of fresh tumor tissue at surgery could greatly improve the success of DNA extraction and methyl guanine methyl transferase (MGMT) promoter methylation testing. The concentration of the DNA samples can also be improved from a withdrawal in an area with a high probability of neoplastic cells.

Methods

The present study reports the results of ten frameless image-guided intracranial needle biopsies from April 2008 until February 2009, among a total of 28 frameless neuronavigation brain biopsy performed from May 2007 to February 2009. The protocol sampling provided withdrawal specimens correlated with neuroimaging characteristics of the lesions. The molecular determination of MGMT promoter was assessed with the nested methylation-specific polymerase chain reaction on fresh or cryopreserved needle bioptic tissue.

Results

The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in six patients, including a brain infection. The image-guided trajectory of the biopsy and the intraoperative frozen section increased the diagnostic yield.

Conclusions

To the best of the authors' knowledge, this is the first report with the MGMT promoter status analysis on needle bioptic fresh tissue. In the future, the availability of the molecular genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment.  相似文献   
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