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101.
G Gualdrini P Battisti R Biagini P De Felice A Fazio P Ferrari 《Applied radiation and isotopes》2000,53(1-2):387-393
The investigation of actinides' internal contamination in human body makes use of a variety of techniques. In large scale screening the technique of "in vivo" evaluation of bone 241Am burden via the determination of the nuclide activity in the skull is often used. For this purpose, adequate calibration procedures and standard phantoms are needed. The present paper summarises the studies and technical procedures followed for the development of a calibration phantom based on a commercial Alderson angiographic head in which a set of 24 241Am point sources were embedded. A theoretical study was first carried out, at the ENEA Institute for Radiation Protection, using the MCNP4-B Monte Carlo code to determine the point source distribution that closely approximates a homogeneous bone contamination. The numerical models were also used to evaluate the resulting degree of approximation. The point sources were prepared at the ENEA National Metrology Institute for ionising radiation quantities and were traceable to the Italian national standard of radionuclide activity. The sources were prepared by quantitatively dispensing a liquid solution onto a plastic disc. The activity of each source was checked by gamma-ray spectrometry and the reproducibility of the activity values was determined. Each source was then placed in the optimum position in the skull, given by the Monte Carlo modelling, by a precision mechanical device. The phantom was finally used to calibrate a whole body counter operating at the ENEA Institute for Radiation Protection. The paper reports the main theoretical and experimental aspects of this work, and also discusses the results of the first calibrations. 相似文献
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Pignatti G Ferrari D Tigani D Scardovi M Trentanti P Trentani F Giunti A 《La Chirurgia degli Organi di Movimento》2000,85(4):381-387
The authors present the results observed in 12 patients affected with post-traumatic stiffness of the elbow treated by an external fixator in distraction to obtain functional recovery of range of movement; in all of the cases anterior and posterior release and resection of the apex of the olecranon was carried out, while in 2 cases interposition arthroplasty with freeze-dried dura madre was associated. The series includes 12 cases with a long-term follow-up that ranges from 8 to 33 months after surgery. The mean arch of movement during the preoperative phase was 35 degrees (minimum 0 degree-maximum 90 degrees) in flexion extension and 80 degrees (minimum 0 degree-maximum 150 degrees) in pronosupination. Recovery of mean joint excursion in flexion-extension was 91 degrees and in pronosupination it was 127 degrees. Complications included loosening of the nails in 2 cases, breakage of the nails in 1 case, and transitory deficit of the ulnar nerve in 4 cases. A total of 11 patients (91.66%) declared that they were satisfied with the considerable improvement in their ability to do daily activities. The results of arthroplasty in distraction in the elbow are satisfactory even if much attention must be paid to the selection of the patients because of the intense collaboration that is required during postoperative rehabilitation. 相似文献
104.
Evasio Pasini Anna Cargnioni Fiorella Pastore Roberta Razzetti Stefano Bongrani Gian Luca Gitti Roberto Ferrari 《Pharmacological research》2004,49(1):1-5
Neurohormonal activation has been shown to be a major factor in congestive heart failure progression and mortality. The beneficial effects obtained in clinical trials with angiotensin converting enzyme (ACE) inhibitors, beta-blockers and aldosterone antagonists have confirmed this hypothesis. 5,6-Diisobutirroyloxy-2-methyl-aminotetraline hydrochloride (nolomirole) is a selective agonist of prejunctional D(2)-dopaminergic and alpha(2)-adrenergic receptors. The stimulation of these receptors inhibits catecholamine release from sympathetic nerve endings. To confirm that this mechanism can be useful in congestive heart failure, we studied the effects of nolomirole on monocrotaline-induced congestive heart failure. The ACE inhibitor trandolapril was used as reference compound. Rats were given single intraperitoneal injection of either saline (control group; n=20) or monocrotaline (50 mg kg(-1)). Three days later, the monocrotaline-treated animals were randomly allocated (n=50 per group) to oral treatment with distilled water (vehicle group), nolomirole (0.25 mg kg(-1)) twice a day, or trandolapril (0.3 mg kg(-1)) once a day up to sacrifice. On the fourth week after monocrotaline injection, animals with signs of congestive heart failure were sacrificed for evaluation of heart hypertrophy and neuroendocrine alterations. Atrial natriuretic peptide (ANP) and alderosterone were determined by radioimmunoassay in plasma. Tissue norepinephrine concentration was quantified by high-pressure liquid chromatography. Nolomirole and trandolapril significantly reduced (a) hypertrophy of right atria and ventricles, (b) plasma levels of ANP and presence of pleural/peritoneal effusions and (c) norepinephrine depletion of right ventricle. These findings confirmed that nolomirole, like trandolapril, is able to attenuate the heart failure signs in the monocrotaline-induced congestive heart failure model. 相似文献
105.
Giuseppina Sandri Silvia Rossi Franca Ferrari Maria Cristina Bonferoni Corrado Muzzarelli Carla Caramella 《European journal of pharmaceutical sciences》2004,21(2-3):351-359
The aim of the present work was to evaluate the mucoadhesive and penetration enhancement properties via the buccal and vaginal mucosae of four different chitosan derivatives: 5-methyl-pyrrolidinone chitosan (MPC), two low molecular weight chitosans (DC1 and DC2) and a partially reacetylated chitosan (RC). Chitosan HCl was used as a reference. Polymer solutions (4% w/w) were prepared in media simulating the buccal (pH 6.4 buffer or water) and the vaginal (pH 5.0 buffer) environments and subjected to rheological characterization. Acyclovir was added to the polymer solutions at 5% (w/w) concentration. The mucoadhesive properties of the polymer solutions were measured using excised porcine cheek or vaginal mucosa and mucin dispersions to simulate the buccal or vaginal environments, respectively. Drug permeation and penetration tests were carried out using porcine cheek and vaginal mucosae as model membranes. Acyclovir aqueous suspensions prepared in pH 6.4 and 5.0 buffers were used as blanks. Drug release measurements were also carried out in the same conditions employed for the permeation and penetration tests. Methyl-pyrrolidinone chitosan shows the best mucoadhesive and penetration enhancement properties in both buccal and vaginal environments. The capability to enhance the permeation/penetration of acyclovir was decreased by partial depolymerization of chitosan and disappeared after partial reacetylation. 相似文献
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109.
Clarissa J. Diamantidis David J. Cook Stephan Dunning Cyd Kristoff Redelosa Martin Francis D. Bartolome Roland Albert A. Romero Joseph A. Vassalotti 《Journal of general internal medicine》2022,37(16):4241
BackgroundChronic kidney disease (CKD) is a common condition with adverse health outcomes addressable by early disease management. The impact of the COVID-19 pandemic on care utilization for the CKD population is unknown.ObjectiveTo examine pandemic CKD care and identify factors associated with a high care deficit.DesignRetrospective observational studyParticipants248,898 insured individuals (95% Medicare Advantage, 5% commercial) with stage G3–G4 CKD in 2018Main MeasuresPredicted (based on the pre-pandemic period of January 1, 2019–February 28, 2020) to observed per-member monthly face-to-face and telehealth encounters, laboratory testing, and proportion of days covered (PDC) for medications, evaluated during the early (March 1, 2020–June 30, 2020), pre-vaccine (July 1, 2020–December 31, 2020), and late (January 2021–August 2021) periods and overall.Key ResultsIn-person encounters fell by 24.1% during the pandemic overall; this was mitigated by a 14.2% increase in telehealth encounters, resulting in a cumulative observed utilization deficit of 10% relative to predicted. These reductions were greatest in the early pandemic period, with a 19.8% cumulative deficit. PDC progressively decreased during the pandemic (range 9–20% overall reduction), with the greatest reductions in hypertension and diabetes medicines. CKD laboratory monitoring was also reduced (range 11.8–43.3%). Individuals of younger age (OR 1.63, 95% CI 1.16, 2.28), with commercial insurance (1.43, 95% CI 1.25, 1.63), residing in the Southern US (OR 1.17, 95% CI 1.14, 1.21), and with stage G4 CKD (OR 1.21, 95% CI 1.17, 1.26) had greater odds of a higher care deficit overall.ConclusionsThe early COVID-19 pandemic resulted in a marked decline of healthcare services for individuals with CKD, with an incomplete recovery during the later pandemic. Increased telehealth use partially compensated for this deficit. The downstream impact of CKD care reduction on health outcomes requires further study, as does evaluation of effective care delivery models for this population.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07805-w.KEY WORDS: chronic kidney disease, COVID-19, epidemiology 相似文献
110.
Luca Ferrari Francesca Fumagalli Nicoletta Rizzi Elisa Grandi Serena Vailati Michele Manoni Matteo Ottoboni Federica Cheli Luciano Pinotti 《Toxins》2022,14(11)
Aflatoxins (AFs) remain the main concern for the agricultural and dairy industries due to their effects on the performances and quality of livestock production. Aflatoxins are always unavoidable and should be monitored. The objective of this paper is to bring to light a significant volume of data on AF contamination in several animal feed ingredients in Northern Italy. The Regional Breeders Association of Lombardy has been conducting a survey program to monitor mycotoxin contamination in animal feeds, and in this paper, we present data relating to AFB1 contamination. In most cases (95%), the concentrations were low enough to ensure compliance with the European Union’s (EU’s) maximum admitted levels for animal feed ingredients. However, the data show a high variability in AF contamination between different matrices and, within the same matrix, a high variability year over year. High levels of AFs were detected in maize and cotton, especially in the central part of the second decade of this century, i.e., 2015–2018, which has shown a higher risk of AF contamination in feed materials in Northern Italy. Variability due to climate change and the international commodity market affect future prospects to predict the presence of AFs. Supplier monitoring and control and reduced buying of contaminated raw materials, as well as performing analyses of each batch, help reduce AF spread. 相似文献