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排序方式: 共有188条查询结果,搜索用时 31 毫秒
1.
A Balbarini M Rugolotto F Buttitta R Mariotti G Strata M Mariani 《Canadian Metallurgical Quarterly》1998,43(6):605-615
Deep vein thrombosis (DVT) has a high social and economic cost disease being its prevalence in the general population elevated and producing possibly fatal (pulmonary embolism) or disabling (post-thrombotic syndrome) complications. Thus, it appears of great importance to know the epidemiological and clinical characteristics of DVT in order to perform the best diagnosis, therapy and prophylaxis. The study population is composed by 146 patients (84 males and 62 females, mean age 60.9 +/- 15.3 years, range 19.92 years), arrived in our Vascular Echography Laboratory with the clinical suspect of DVT confirmed by means of echo color Doppler. The most frequent clinical signs were skin hyperthermia in 118 patients (80.8%) and edema in 116 patients (79.5%), while the most common symptom was pain, 89 patients (61.0%). Eleven patients (7.5%) were asymptomatic. The echo criteria utilized were direct thrombus visualization, vessel diameter higher than the contralateral, reduced or absent vessel wall ability to be compressed, reduced or absent color Doppler venous flow, lack or reduction of respiratory flow modulation, visualization of collateral circulation. DVT was located in 131 patients (89.7%) in inferior limbs (proximal in 122 patients, isolated distal in 9 patients), in 14 patients (9.6%) in superior limbs and in 3 patients (2.1%) in the internal jugular vein. In 130 patients a risk factor or a predisposing condition was identified: secondary DVT; in 16 patients the DVT was considered idiopathic. The most frequent risk factors were: previous surgery 28.1%, immobilization 19.9% trauma 17.1%, tumors 9.6%. A hypercoagulation was detected in 4 patients: antithrombin III deficit in 2, post-splenectomy thrombocytosis in 1 and antiphospholipid antibodies syndrome in the last one. The Pisa territory epidemiologic data showed a male 0.51 and female 0.38/1000 subject/year DVT incidence, with significantly higher values in older than 45-54 males and 55-64 females. One hundred and thirty one patients were treated with 5-11 day heparin infusion and thereafter with warfarin at least for 6 months, 1 year or indefinitely depending on thromboembolic risk. Six patients with distal DVT and 9 patients with hemorrhagic risk were treated with subcutaneous calcic or low weight heparin. In 1 patient with a mobile thrombus judged as at very high risk of embolization, a caval filter was positioned. Anticoagulant therapy complications were: 2 minor bleedings, 1 alopecia, 1 thrombocytopenia. Two patients died for neoplastic complications. Fifty-seven patients completed a 6-month follow-up and were submitted to a control each study that evidenced: total recanalization in 15 (26.3%), partial recanalization in 25 (43.9%) and no recanalization in 17 patients (29.8%). In 6 patients there was a DVT relapse and in 9 pulmonary embolization: almost all these patients were in the partial recanalization group. 相似文献
2.
Tortoli P Guidi G Mariotti V Newhouse VL 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1992,39(2):196-203
A line flow of scatterers crossing the sound field produced by a focused circular transducer at uniform velocity originates a quasi-triangular Doppler spectrum. It is known that the spectrum shape and width depend on the line flow to beam axis angle, as well as on the transducer geometry. It has recently been theoretically predicted that this spectrum width is independent of the flow line location in the sound field. Experimental verification of the new theorem, based on the use of a thread phantom operated at various orientations, ranges, and offsets, with respect to the ultrasound transducer, is presented. The tests were made with a computerized pulsed Doppler system designed to perform optimal real-time spectral analysis of data obtained in this application. The prototype system and the experimental procedure adopted for demonstrating in vitro the invariance of the Doppler spectral bandwidth are described. 相似文献
3.
4.
This review provides an evaluation of the correlates and/or risk factors associated with disordered eating and the pursuit of muscularity among adolescent boys. One of the main conclusions is that similar factors and processes are associated with both behavioral problems. Several factors found to be consistently associated with disordered eating among boys are also similar to those found with girls. These include body mass index, negative affect, self-esteem, perfectionism, drug use, perceived pressure to lose weight from parents and peers, and participation in sports that focus on leanness. However, as many of the findings have only been verified using cross-sectional designs, prospective studies are now needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Oluwamolakun Bankole Ilaria Scambi Edoardo Parrella Matilde Muccilli Roberta Bonafede Ermanna Turano Marina Pizzi Raffaella Mariotti 《International journal of molecular sciences》2022,23(3)
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disorder. There is no cure and current treatments fail to slow the progression of the disease. Epigenetic modulation in the acetylation state of NF-kB RelA and the histone 3 (H3) protein, involved in the development of neurodegeneration, is a drugable target for the class-I histone deacetylases (HDAC) inhibitors, entinostat or valproate, and the AMP-activated kinase (AMPK)-sirtuin 1 pathway activator, resveratrol. In this study, we demonstrated that the combination of valproate and resveratrol can restore the normal acetylation state of RelA in the SOD1(G93A) murine model of ALS, in order to obtain the neuroprotective form of NF-kB. We also investigated the sexually dimorphic development of the disease, as well as the sex-sensibility to the treatment administered. We showed that the combined drugs, which rescued AMPK activation, RelA and the histone 3 acetylation state, reduced the motor deficit and the disease pathology associated with motor neuron loss and microglial reactivity, Brain-Derived Neurotrophic Factor (BDNF) and B-cell lymphoma-extra large (Bcl-xL) level decline. Specifically, vehicle-administered males showed earlier onset and slower progression of the disease when compared to females. The treatment, administered at 50 days of life, postponed the time of onset in the male by 22 days, but not in a significant way in females. Nevertheless, in females, the drugs significantly reduced symptom severity of the later phase of the disease and prolonged the mice’s survival. Only minor beneficial effects were produced in the latter stage in males. Overall, this study shows a beneficial and sexually dimorphic response to valproate and resveratrol treatment in ALS mice. 相似文献
6.
Miia Turpeinen Jouko Uusitalo Terhi Lehtinen Marita Kailaj?rvi Olavi Pelkonen Jouni Vuorinen Pasi Tapanainen Camilla Stjernschantz Risto Lammintausta Mika Scheinin 《International journal of molecular sciences》2013,14(7):14064-14075
The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low. 相似文献
7.
Francesca Bugli Federica Massaro Francesco Buonocore Paolo Roberto Saraceni Stefano Borocci Francesca Ceccacci Cecilia Bombelli Maura Di Vito Rosalba Marchitiello Melinda Mariotti Riccardo Torelli Maurizio Sanguinetti Fernando Porcelli 《International journal of molecular sciences》2022,23(4)
The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens. 相似文献
8.
Yurong Ma Qingguo Wang Gyunghoon Hong Marita Cantwell 《International Journal of Food Science & Technology》2010,45(7):1486-1494
The cultivar Pacific Russet with high browning susceptibility was used for most testing. Controlled atmospheres (0.3%, 3% and 21% O2 in combination with 0%, 6% or 12% CO2) and anti‐browning chemicals were studied in relation to quality retention and wound‐induced phenolic metabolism of fresh‐cut slices for up to 16 days at 5 °C. The 3% O2+ 12% CO2 atmosphere was most effective among those tested, and retarded increases in phenolics and phenylalanine ammonia lyase activity, but had only slight benefit on visual quality. A 1.25% ascorbic acid +1.25% citric acid treatment was ineffective, but when combined with 3% O2+ 12% CO2, it was comparable with 0.025% sodium bisulphite. Bisulphite concentrations from 0.05% to 0.25% provided similar effective control of discolouration. Bisulphite as low as 0.025% with 3% O2+ 12% CO2 resulted in a visual quality score at the limit of marketability after 8 days at 5 °C. Chemical treatments did not retard increases in phenolic concentrations or phenolic enzyme activities. 相似文献
9.
Anthony Fardet Anne Morise Esther Kalonji Irène Margaritis François Mariotti 《Critical reviews in food science and nutrition》2017,57(9):1906-1921
Phytosterols and phytostanols (PAP) compete with cholesterol absorption in the intestine, resulting in a 5–15%-reduction in plasma total and LDL cholesterol. An important issue is the PAP potential to reduce the plasma concentrations of fat-soluble vitamins and provitamin A carotenoids. Here, an update of the scientific evidence is reviewed to evaluate plant PAP-enriched foods impact on plasma fat-soluble vitamins and carotenoid levels, and to discuss potential implications in terms of cardiovascular risk. Based on 49 human interventional and 3 bioavailability studies, results showed that regular consumption, particularly over the long term, of foods fortified with PAP as recommended in labeling does not significantly impact plasma vitamins A, D, and K concentration. A 10% significant median reduction was observed for α-tocopherol. Concerning carotenoids, while 13 studies did not demonstrate statistically significant plasma β-carotene reduction, 20 studies showed significant reductions, with median effect size of ?24%. This decline can be mitigated or offset by increased fruits and vegetables consumption. Furthermore, higher cardiovascular risk was observed for differences in plasma β-carotene concentration of the same magnitude as the estimated average decrease by PAP consumption. These results are supported by the only study of β-carotene bioavailability showing decrease in absorption by phytosterols daily intake. 相似文献
10.
This paper aims to clarify current knowledge on the contribution of communication to crisis management in the case of terrorism incidents. This is done by means of a systematic review of the scientific literature on terrorism communication over the last 10 years to identify the many challenges facing communication in such crises, and represents the first attempt of its kind. To date, within the literature on terrorism communication, much attention has been paid to chemical, biological, radiological or nuclear hazards. Terrorism crises are complex and challenging. Preparedness for such diverse low‐probability high‐impact crises can best be included in a wider educative approach. Terrorism crises call for fast information updates that, using a multi‐channel approach, can be tailored to fit different needs and (social) media habits. 相似文献