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Biomedical subjects

G Cristoforetti

Publications and source records attributed to G Cristoforetti.

8 recordsLinked to original sources
PubMed2006

Resolving surface details with reflection and fluorescence video-confocal profilometry.

Video-confocal profilometry has been exploited to characterize reflecting and non-reflecting surfaces in materials with tilted and corrugated areas. An alternative method based on fluorescence detection has been developed and tested to characterize metal surfaces modified by intense laser irradiation. Combined representations of surface topography have been obtained on the basis of both reflectance and fluorescence signals. A discussion of results and problems encountered in reflection and fluorescence based techniques is provided.

Journal Article↗
PubMed2006

Modì: a new mobile instrument for in situ double-pulse LIBS analysis.

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for in situ elemental analysis. A new mobile instrument for LIBS analysis, developed in a collaboration between Marwan Technology s.r.l. and the Applied Laser Spectroscopy Laboratory in Pisa, is presented, and some applications of it and results from it are outlined. The innovative experimental set-up, based on the use of two suitably retarded laser pulses and a standardless analysis procedure, which overcomes problems related to matrix effects, greatly improves the potential of this technique for accurate quantitative analysis.

Journal Article↗
PubMed2003

Temporal and spatial evolution of a laser-induced plasma from a steel target.

The space and time evolution of a laser-induced plasma from a steel target has been studied using optical time-of-flight and shadowgraphic techniques. The results, obtained for two distinct laser energy regimes, allow us to individuate two different regions in the plume, one characterized by air and continuum emissions produced by the shock wave ionization and the other characterized by emissions from ablated material. Moreover, it was shown that a sufficiently high laser fluence and short delay time of acquisition are needed to avoid inhomogeneous effects in the plasma, as required in analytical applications such as laser-induced breakdown spectroscopy.

Gases↗
PubMed1984

Selective PF4 release in vitro induced by heparin and related glycosaminoglycans (GAGs)--correlation with beta-TG release and platelet aggregation.

We studied human platelet aggregation and beta-TG/PF4 release induced by heparin and related GAGs in vitro both in normal PRP and in PRP after aspirin. In our experimental conditions, heparin and related GAGs always caused PF4 release in vitro from normal platelets, whether or not there was measurable platelet aggregation in the aggregometer. Significant beta-TG release was induced only by the mucosal heparin preparation (which also induced platelet aggregation in some citrated PRP). Therefore, while beta-TG release in vitro seems to correlate with platelet aggregating activity of heparin, the selective PF4 release, caused by heparin and related GAGs also in conditions in which neither platelet aggregation nor beta-TG are measurable, is probably associated with the high affinity of PF4 for heparin. The degree of affinity of GAGs for PF4 (heparin greater than DeS greater than HS) seems to correlate with PF4 release. Moreover, the significant reduction in PF4 release in vitro after aspirin suggests that GAGs-induced PF4 release is related to a cyclooxygenase-dependent activation process.

Adenosine Diphosphate↗
PubMed1984

Value of CT scanning in the diagnosis of CNS mycotic involvement: report of 3 cases.

Fungal infections of the CNS are becoming an increasingly serious problem in immunosuppressed patients. We describe three patients with malignant blood disease who in the course of systemic fungal infection presented cerebral involvement. The nature, site and extent of the cerebral involvement were defined by computed tomography (CT). Further, in one patient it was possible to follow the course of the lesion and assess the effectiveness of antimycotic therapy by CT because of its noninvasiveness and repeatability.

Adult↗
PubMed1982

Low-dose heparin in thoracic surgery: effect on blood coagulation and fibrinolysis system.

Plasma kallikrein, antithrombin III and antiplasmin were determined with chromogenic methods in 29 patients pre-, per- and post-operatively in a controlled, randomized study. 16 patients received calcium heparin, 5000 IU s. c. every 8 hr for 7 days, the first administration given 2 hr before surgical procedure. 13 control patients received saline. A significant reduction of kallikrein and antiplasmin in per- and post-operative periods was observed in the control patients compared with the heparin-treated patients, while there was a significant reduction of anti-thrombin III in the control patients compared with the treated patients only in the per-operative period. The results obtained suggest that activation of the coagulation and fibrinolysis system occurs in patients undergoing thoracic surgery, and that it is inhibited significantly by calcium heparin prophylaxis.

Adult↗
PubMed1982

Beta-thromboglobulin and platelet factor 4 plasma levels during haemodialysis: effect of indobufen.

The effect of a single dose of indobufen (100 mg i.v.) on the release of beta-thromboglobulin and of the platelet factor 4 was investigated during dialysis in 20 uraemic subjects by a within-subjects, single-blind, indobufen versus placebo study. Plasma levels were measured in baseline conditions and 15, 30, 60, 120 and 240 minutes after the beginning of dialysis. Pre-treatment with indobufen clearly inhibited beta-TG and PF 4 output. The difference from placebo was highly significant (p less than 0.01) from the 30-minute control up to the end of dialysis. No changes in platelet count before and after dialysis were observed.

Adult↗