111 research outputs found
Fattori di conversione delle unità di misura convenzionali in Unità Internazionali (SI)
No full text
Manuale per valutazione e inquadramento di patologie surrenaliche e ipertensione arteriosa endocrina
No full textA direct injection high-performance liquid chromatographic method with electrochemical detection for the determination of ethanol and methanol in plasma using an alcohol oxidase reactor
No full textA highly sensitive reversed-phase high-performance liquid chromatographic assay for ethanol and methanol in plasma, using a post-column enzymic reactor with electrochemical detection, has been developed. The alcohols, separated on the column, were converted by immobilized alcohol oxidase into their respective aldehydes with formation of stoichiometric amounts of hydrogen peroxide, detected via oxidation at a platinum electrode. As the chromatographic column, two glass cartridges (150 mm x 3 mm I.D.) in series, packed with 10 microns HEMA-S 1000 packing, were used. Alcohol oxidase from Candida boidinii was immobilized onto HEMA-BIO 1000 VS-L (10 microns), packed in a 30 mm x 3 mm I.D. glass cartridge. The reaction product, hydrogen peroxide, was detected with an amperometric detector with a platinum electrode, operated at +500 mV vs. an Ag/AgCl reference electrode. A 20-microliters volume of ten-fold diluted plasma was injected without any pre-treatment. Under the described conditions, methanol and ethanol were well resolved from each other and from the "front" of the chromatogram. The limit of detection was ca. 2.5 nmol for ethanol and 0.6 nmol for methanol in plasma, at a signal-to-noise ratio of 3. Excellent linearity was observed for ethanol, in the range 0.125-4 micrograms injected (r = 0.9999). In contrast, the response for methanol was markedly non-linear above 500 micrograms injected, presumably owing to progressive saturation of the reactor. The precision and accuracy of the assay were satisfactory, as was the reactor life (one month)
The brief history of laryngoscope: From lyric theater to operating theater | La breve storia del laringoscopio: dal teatro lirico al teatro operatorio
No full textTracheal intubation is one of the most widely used manoeuvres and laryngoscope is one of the most used devices in medicine. The first mentioned laryngoscopy is attributed to the Roman physician Aulus Cornelius Celsus. In the following centuries the contributions of Andreas van Wesel, known also with his Italian name Vesalio, of the English scientists Robert Hooke and Benjamin Guy Babington and the efforts of the German-Italian physician Philipp Bozzini and, particularly, of the Spanish singing teacher Manuel Patricio Rodríguez García were important. The ancestor of the laryngoscope used today was built by Alfred Kirstein, while the straight blades were designed by Robert Arden Miller and the curve blades by Robert Reynold Macintosh, respectively in 1941 in United States and in 1943 in United Kingdom. Only with Henry Harrington Janeway the laryngoscope lost its diagnostic function and became the essential device for tracheal intubation. Nowadays, the “digital revolution” of 21th century has brought newer technology to the science of tracheal intubation, and the GlideScope, a laryngoscope incorporating a video camera connected to a high resolution LCD monitor designed by the surgeon John Allen Pacey, is one of the most recent devices
Altered thyroid in dialysed uremic patients
No full textThyroid abnormalities were studied in 40 uremic patients half of whom were receiving hemodialysis and half peritoneal dialysis. The following parameters were examined in all patients: total and free thyroxinemia, free and total triiodothyroninemia, basal thyreotropinemia and levels 20 mins after releasing hormone (TRH) stimulation, reverse T3, thyroglobulinemia, antithyroglobulin , antimicrosomial and antithyroperoxidase antibodies; a thyroid echography was also performed. Numerous alterations were found in thyroid parameters, with a greater frequency in hemodialysed patients (65%) than those undergoing peritoneal dialysis (52.5%). Among the parameters examined it is worth noting that total thyroxinemia was significantly reduced compared to controls, and FT3 was very significantly reduced. Among those patients undergoing peritoneal dialysis thyreotropinemia was increased in 6 cases (15%), whereas among hemodialysed patients it was reduced in 2 cases (5%). Ten patients (25%) in all appeared to be free of thyroid alterations and 30 (75%) showed one or more alteration of the parameters examined. Of the latter, 1 case of toxic multinodular goiter, 1 case of Plummer's adenoma in a pretoxic phase, 1 case of hypothyroidism, 15 cases of "sick euthyroid of syndrome", 3 cases with high antibody levels and 2 cases of single node goitre were diagnosed. The study confirmed the high incidence of thyroid alterations in uremic patients and, surprisingly, allowed the authors to diagnose a case of toxic multinodular goitre and a case of Plummer's adenoma at a pretoxic phase. The authors discuss the rarity of thyroid hyperfunction in uremia and suggest the need to consider patients with chronic renal insufficiency as being at risk of hypo-, normo- and hyperfunctioning thyreopathy, and to use a routine thyreotropinemia assay in all uremic patients
Liquid chromatography with pre-column dansyl derivatisation and fluorimetric detection applied to the assay of morphine in biological samples
No full textA simple method employing pre-column dansylation and liquid chromatography is proposed for a very sensitive and specific assay of morphine in biological samples. Nalorphine is used as an internal standard. The detection limit is 0.2 picomol of injected morphine. In the assay of human sera spiked with 150 nmol/l, the intra- and inter-assay coefficients of variation were 3.7% (n = 10) and 4.5% (n = 10), respectively. No interferences were observed from more than 70 opiate and non-opiate drugs. Urine, plasma and total blood were assayed, using different extraction methods, with negligible interference from coextractives
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