1,720,960 research outputs found
The metanalysis of antiplatelet treatment trials. A proposal of an additional key of lecture [La metanalisi dei trial di terapia antiaggregante. Proposta di una chiave aggiuntiva di lettura]
No full textThe efficacy of drug treatment is conventionally assessed by clinical trials. In these studies, experimental design, data analysis and interpretation of results are based on statistical methods. It is difficult to relate to a specific patient the data obtained from statistically analysed studies of population. In our opinion the statistical parameter NNT (Number of patients Needed to Treat) indicates the effectiveness of a treatment taking into consideration the basal risk as well as the risk reduction after therapy. We applied the NNT parameter to data taken from the metanalysis Antiplatelet Trialists' Collaboration concerning secondary prevention of adverse vascular events with antiplatelet drugs. We focused on the long-term effect of antiplatelet therapy on the adverse events reduction; in the first year of treatment we observed a NNT value of 37, in the second year a NNT value of 59 and in the third year a NNT value of 200; in the fourth year we found absence of effect. The NNT parameter allows us to evaluate immediately the economic consequences of therapeutic strategies and the clinical impact of a long-term treatment
New trends in docimology. Multiple-choice test using automated procedures [Nuove acquisizioni di docimologia. L'utilizzo di test a scelta multipla mediante una procedura automatizzata]
No full textCosts determination in hospital enterprises. Administrative costs and operating aspects [La determinazione dei costi nelle aziende ospedaliere. Valenze gestionali ed aspetti operativi]
No full textComparison of time – frequency distribution techniques applied to a simulated carotid doppler signal
No full textNimodipine:drug pharmacokinetics and plasma adenosine levels in patients affected by cerebral ischemia
No full textIncrease of adenosine plasma levels after oral trimetazidine: a pharmacological preconditioning?
No full textTrimetazidine (1-[2,3,4-trimethoxybenzyl] piperazine) (TMZ) is a cellular anti-ischemic agent able to prevent intracellular ATP decrease, limit intracellular acidosis, protect against oxygen-free radical-induced toxicity and inhibit neutrophil infiltration. However, its definitive mechanism of action had not been identified. Recent studies showed the existence of an endogenous mechanism of cellular protection against ischemia, defined as 'ischemic preconditioning'. This mechanism was related mainly to cellular liberation of adenosine, a nucleoside with protective effects in myocardial ischemia. Since TMZ acts by increasing cell tolerance to ischemia and adenosine is the mediator of ischemic preconditioning, in this study we investigated a possible interaction between TMZ and adenosine. Two groups of patients affected by angina pectoris, were admitted to the study. They received a single oral dose of TMZ. One group was treated, during different sessions, with TMZ 10 and 20 mg, the other group with TMZ 40 and 80 mg. After a 3 day wash-out from drug administration, each group received a placebo. Blood samples were collected at baseline (time 0) and 1, 2, 3, 4, 6, 8 h after drug administration, in order to detect plasma levels of adenosine by a high-performance liquid chromatography method. We observed that the administration of TMZ at doses of 10, 20, 40 and 80 mg induced an increase of adenosine plasma levels of 19, 50, 62 and 62%, respectively. We hypothesized that the activity of TMZ could depend, at least in part, on adenosine mediation and this interaction opens a new interpretation of the drug antischemic effect. © 2002 Elsevier Science Ltd
Diurnal rhythm of the anticoagulant effect of continuous i.v. infusion of unfractioned heparin: a possible role for platelet activation
No full textVariazioni diurne dell’ effetto anticoagulante dell’ eparina non frazionata in corso di infusione continua e.v. nell’ uomo. Modificazioni indotte da acido acetlsalicico per os
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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