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C Colombi

Publications and source records attributed to C Colombi.

9 recordsLinked to original sources
PubMed2002

Fricke gel dosimetry in boron neutron capture therapy.

Gel dosimetry allows three-dimensional (3D) measurement of absorbed dose in tissue-equivalent dosemeter phantoms. Gel phantoms are imaged using optical techniques. In neutron capture therapy (NCT), properly designed gel dosemeters can give 3D dose distributions, due to the various components of the secondary radiation, in phantoms exposed in the thermal or epithermal column of a nuclear reactor. In addition to the therapeutic dose arising from the reaction 10B(n,alpha)7Li, the other dose components are also obtainable, i.e. the gamma dose (due to reactor background and to the reaction 1H(n,gamma)2H of thermal neutrons with hydrogen, the dose due to protons emitted in the reaction 14N(n,p)14C of thermal neutrons with nitrogen and the dose due to recoil protons resulting from elastic scattering of epithermal neutrons.

Boron Neutron Capture Therapy↗
PubMed1995

Comparison between depot leuprorelin and daily buserelin in IVF.

OBJECTIVES: To compare the effects of depot and daily forms of GnRH analogs in IVF programs. METHODS: One hundred seventeen patients undergoing IVF, with no severe male factor, were randomized between two treatment groups. Pituitary desensitization was obtained in group 1 (60 patients) with a single IM injection of leuprorelin (3.75 mg), and in group 2 (57 patients) with buserelin (0.3 mg SC twice daily). In a subgroup of 10 patients (5 for the depot form and 5 for the daily form) several GnRH tests were performed to investigate pituitary desensitization. RESULTS: No differences were found in the time to reach desensitization. Resumption of pituitary activity occurred in 7 days with the daily form and in about 2 months with the depot form. No significant differences were found in the stimulation pattern, oocyte quality, percentage of fertilization. The pregnancy rate per transfer was slightly, but not significantly, better in the depot group (29.4% vs 25.9%). Implantation rate (11.9% vs 12.3%) and the percentage of miscarriages (26.6% vs 28.5%) were similar. CONCLUSION: Depot and daily forms of GnRH analogs are equally effective in superovulation induction for IVF. Considering improved patient compliance and preference, depot forms are advantageous.

Abortion, Spontaneous↗
PubMed1995

Gamete intrafallopian transfer: prospective randomized comparison between hysteroscopic and laparoscopic transfer techniques.

OBJECTIVE: To test the efficiency and overall acceptability of hysteroscopic GIFT when compared with laparoscopic GIFT. DESIGN: We performed a randomized comparison between these techniques as regards pregnancy rate (PR), implantation rate, miscarriage rate, and ectopic pregnancy rate (ectopic PR). SETTING: All patients were enrolled for GIFT procedures in our Reproductive Medicine Unit. PATIENTS: We enrolled 133 patients showing documented tubal patency at a previous diagnostic laparoscopy. INTERVENTIONS: Gonadotropin-releasing hormone analog and FSH were administered to induce superovulation in all patients, who were then randomized for hysteroscopic GIFT or laparoscopic GIFT. Laparoscopic GIFT was performed under general anesthesia while, during hysteroscopic GIFT, oocyte retrievals were transvaginal ultrasound guided and transfers were performed by cannulating tubal ostia after hysteroscopic visualization. MAIN OUTCOME MEASURE: The efficacy was evaluated comparing PR, implantation rate, miscarriage rate, and ectopic PR. RESULTS: Pregnancy rate and implantation rate of hysteroscopic GIFT procedures (29.8% and 9%, respectively) are not significantly different from those obtained with laparoscopic GIFT (43.3% and 14%). CONCLUSIONS: Hysteroscopic GIFT is safe and easy and quick to perform. Moreover, it does not require hospital admission, general anesthesia, or the operating theater, reducing costs and assuring advantages in terms of low psychophysical involvement and repeatability.

Adult↗
PubMed1994

Transfusion-dependent homozygous beta-thalassaemia major: successful twin pregnancy following in-vitro fertilization and tubal embryo transfer.

Homozygous beta-thalassaemia (thalassaemia major) is a severe, transfusion-dependent anaemia that also causes infertility due to endocrine impairment. Very few pregnancies are reported among such patients and there is only one report in the literature referring to a pregnancy achieved with ovulation induction and intra-uterine insemination. We report here the first successful twin pregnancy following in-vitro fertilization and tubal embryo transfer in a transfusion-dependent homozygous beta-thalassaemic woman with an oligoasthenozoospermic partner. Prior to ovarian stimulation, desferrioxamine was discontinued due to potential fetotoxicity. Pre-gestational transfusional and chelating therapies were resumed after delivery. In such patients, ovulation induction and assisted reproductive techniques appear crucial in achieving pregnancy with concurrent haematological balance without desferrioxamine administration.

Adult↗
PubMed1982

[Deep hypothermia for the correction of a congenital cardiac defect complete with atrioventricular block].

The techniques of deep hypothermia for correction of congenital cardiac defects are well known in many cardiac centers and many cases can be treated even if there are pre-existing rhythm troubles. Our patient had the following diagnosis: left atrial isomerism, dextrocardia; left sided azygos continuation of inferior vena cava; left and right superior venae cavae, hepatic veins, pulmonary veins, all draining into a common atrium; d-loop with normally related ventricles; ventriculo-arterial concordance, small VSD. In addition complete a-v block was present. The patient, 40 days old and 3.4 kg., in heart failure, was paced with a temporary transvenous catheter at 130/min and, afterwards, catheterized. Surgery was undertaken three days post-catheterization using surface deep hypothermia. A Mustard operation, including enlargement of the new left atrium with PTFE (Goretex), was performed during total circulatory arrest. At the end, a permanent pacemaker was positioned in the abdomen and epicardial wires were left on the right ventricle. The postoperative period was uneventful and the patient is doing well 3 months latter. The interest of the case is that even in a complex congenital cardiac malformation with complete a-v block, the technique of surface deep hypothermia can be used because all the physiological parameters remain stable during the procedure in spite of the very low heart rate.

Female↗