324 research outputs found
La centralizzazione degli acquisti permette di spendere “meglio” nel settore sanitario?
Al Servizio Sanitario Nazionale (S.S.N.) è imputabile un volume di spesa per i consumi intermedi che si
aggira sui 30 milioni di euro, di cui la maggior parte gestita in forma aggregata. Quest’ultimo dato
dimostra che, negli anni più recenti, in campo sanitario ha assunto un ruolo di preminente importanza la
tematica delle ricadute di natura organizzativa e gestionale delle procedure degli acquisti di beni e servizi
derivanti dai processi di centralizzazione, nonché dalle politiche di spending review
Behavioral modeling of GaN-based power amplifiers: impact of electrothermal feedback on the model accuracy and identification
In this article, we discuss the accuracy of behavioral models in simulating the intermodulation distortion (IMD) of microwave GaN-based high-power amplifiers in the presence of strong electrothermal (ET) feedback. Exploiting an accurate self-consistent ET model derived from measurements and thermal finite-element method simulations, we show that behavioral models are able to yield accurate results, provided that the model identification is carried out with signals with wide bandwidth and large dynamics
Robot-Assisted Colonic Resections for Cancer
Minimally invasive surgery for colon cancer, if compared with open surgery, has shown similar oncologic outcomes, and it has become the standard management for malignant colonic disease. Its benefits appear yet in early post-operative period such as less postoperative pain, earlier recovery of gastrointestinal functions and shorter hospital stay. Robotic surgery was born in the attempt to overcome the intrinsic limitations of laparoscopic technique. It offers the possibility to have a tridimensional magnified view of surgical field and to use wristed instrument to perform an accurate dissection and lymphadenectomy. It provides the possibility to rotate at 360 degrees the instruments, facilitating considerably the performance of intracorporeal ileo-colic anastomosis in right colectomy. We want to illustrate the feasibility and technique to carry out right and left colectomy in a robotic-assisted way and its advantages with respect to laparoscopic surgery
Results of medium seventeen years' follow-up after laparoscopic choledochotomy for ductal stones
INTRODUCTION:
In a previously published article the authors reported the long-term follow-up results in 138 consecutive patients with gallstones and common bile duct (CBD) stones who underwent laparoscopic transverse choledochotomy (TC) with T-tube biliary drainage and laparoscopic cholecystectomy (LC). Aim of this study is to evaluate the results at up to 23 years of follow-up in the same series.
METHODS:
One hundred twenty-one patients are the object of the present study. Patients were evaluated by clinical visit, blood assay, and abdominal ultrasound. Symptomatic patients underwent cholangio-MRI, followed by endoscopic retrograde cholangiopancreatography (ERCP) as required.
RESULTS:
Out of 121 patients, 61 elderly patients died from unrelated causes. Fourteen patients were lost to follow-up. In the 46 remaining patients, ductal stone recurrence occurred in one case (2,1%) successfully managed by ERCP with endoscopic sphincterotomy. At a mean follow-up of 17.1 years no other patients showed signs of bile stasis and no patient showed any imaging evidence of CBD stricture at the site of choledochotomy.
CONCLUSIONS:
Laparoscopic transverse choledochotomy with routine T-tube biliary drainage during LC has proven to be safe and effective at up to 23 years of follow-up, with no evidence of CBD stricture when the procedure is performed with a correct technique
Applications to cancer research of "lab-on-a-chip" devices based on dielectrophoresis (DEP).
The recent development of advanced analytical and bioseparation methodologies based on microarrays and biosensors is one of the strategic objectives of the so-called post-genomic. In this field, the development of microfabricated devices could bring new opportunities in several application fields, such as predictive oncology, diagnostics and anti-tumor drug research. The so called "Laboratory-on-a-chip technology", involving miniaturisation of analytical procedures, is expected to enable highly complex laboratory testing to move from the central laboratory into non-laboratory settings. The main advantages of Lab-on-a-chip devices are integration of multiple steps of different analytical procedures, large variety of applications, sub-microliter consumption of reagents and samples, and portability. One of the requirement for new generation Lab-on-a-chip devices is the possibility to be independent from additional preparative/analytical instruments. Ideally, Lab-on-a-chip devices should be able to perform with high efficiency and reproducibility both actuating and sensing procedures. In this review, we discuss applications of dielectrophoretic(DEP)-based Lab-on-a-chip devices to cancer research. The theory of dielectrophoresis as well as the description of several devices, based on spiral-shaped, parallel and arrayed electrodes are here presented. In addition, in this review we describe manipulation of cancer cells using advanced DEP-based Lab-on-a-chip devices in the absence of fluid flow and with the integration of both actuating and sensing procedures
K-Band GaAs MMIC Doherty Power Amplifier for Microwave Radio With Optimized Driver
In this paper, a Doherty power amplifier for K-band point-to-point microwave radio, developed in TriQuint GaAs um PWR pHEMT monolithic technology, is presented. Highly efficient driver stages on both the main and auxiliary branches have been designed and optimized to boost gain with minimal impact on power-added efficiency. The selected architecture enables a modular combination to reach higher power levels. Matching network structures have been designed, according to simple equivalent circuit approaches, to obtain the desired 10% fractional bandwidth. The fabricated power amplifier (PA) exhibits, at 24 GHz in continuous-wave conditions, an output power of 30.9 dBm, with a power-added efficiency of 38% at saturation and 20% at 6 dB of output power back-off, together with a gain of 12.5 dB. System-level characterization at 24 GHz, in very demanding conditions, with a 28-MHz channel 7.5-dB peak-to-average ratio modulated signal, showed full compliance with the standard emission mask, adopting a simple predistorter, with average output power of 23.5 dBm, and average efficiency above 14%. The measured performance favorably compare with other academic and commercial K-band PAs for similar applications
Transanal Endoscopic Microsurgery after the attempt of endoscopic removal of rectal polyps
none6The incidence of rectal polyps has steadily increased in
recent decades and will continue to rise. [1] The introduction of endoscopic screening programs has probably contributed to the improved detection of rectal polyps and early
malignant lesions [2, 3]. With the aim to reduce morbidity and mortality of rectal surgery, in 1983, Gerhard Buess
introduced Transanal Endoscopic Microsurgery (TEM) [4].
He conceived a novel endoscopic technology to facilitate the
excision of rectal polyps through the anus [5]. This revolutionary technique enabled superfcial or full-thickness excision of large adenomatous lesions. It soon became apparent
that indications to TEM could be successfully extended to
early malignant polyps [6, 7].
However, in the late nineties, endoscopy was advocated
as a diagnostic technique and a therapeutic method. First,
large piecemeal snare ablations were reported. Then, the
use of endoscopic electrosurgical knives made it possible to
achieve en bloc resection, known as Endoscopic Submucosal
Dissection (ESD) [8–11]. The sharp increase in endoscopic
resection of rectal polyps made the indications for TEM
questioned [12].
This unresolved debate confuses the choice of the optimal treatment for complex rectal polyps. Concerns mainly
arise where there is uncertainty around early malignancy or
where complete resection of an adenomatous polyp is not
obtained following endoscopic attempts [13–15]. Accurate
prognostic information is not always available after endoscopic removal, mainly when the specimen is fragmented.
[16] Additionally, fbrotic tissue growth at the polypectomy
site could invalidate the already sub-optimal accuracy of
pre-operative imaging techniques. Therefore, endoscopic
ultrasound and/or Magnetic Resonance Imaging staging are
often misleading [17]. The indication to resect the site of
a previous endoscopic resection with a full-thickness technique has been recommended in cases of unexpected malignancy. However, the overall beneft remains unclear [13, 18].
This study aims to evaluate the outcomes of TEM following endoscopic resection of rectal polyps performed at two
diferent centres, assess the value of further local excision,
and identify features that may contribute to the decisionmaking process.openMonica Ortenzi, Alberto Arezzo, Roberto Ghiselli, Marco Ettore Allaix, Mario Guerrieri, Mario MorinoOrtenzi, Monica; Arezzo, Alberto; Ghiselli, Roberto; Ettore Allaix, Marco; Guerrieri, Mario; Morino, Mari
Das Bild von sich selbst und Beziehungsentwicklung bei den Adoleszenten
U članku se ističe kako je izgradnja slike o sebi u adolescenciji proces razvoja svijesti o vlastitim sposobnostima i o novoj ravnoteži sa svijetom vlastitih odnosa. Istraživanje, provedeno na uzorku od 280 učenika, potvrđuje kako je prihvaćanje slike o sebi osnaženo uravnoteženjem raznih područja odnosa proučavanih adolescenata i kako ih postupno osposobljava za odgovorniju autonomiju.Im Artikel wird hervorgehoben, wie die Erstellung des Bildes von sich selbst in der Adoleszenz ein Prozeß des vergrößerten Gewissens von der eigenen Fähigung wie auch von neuem Gleichgewicht mit der eigenen Welt der Beziehungen sei. Die Erforschung durchgeführt am Muster von 280 Schülern bestätigt das Akzeptieren des eigenen Bildes, verstärkt durch das ins Gleichgewicht gebrachte Verhältnis mit verschiedenartigen Gebieten der erforschten Adoleszenten und wie es sie zur größeren Autonomie befähigt
Dryocosmus kuriphilus (Hymenoptera cynipidae) in Sardegna
The chestnut gall wasp Dryocosmus kuriphilus was detected in Sardinia in 2007. Two years later its biological control agent, Torymus sinensis, was released and was started the monitoring of native oak gall wasp parasitoids recruited by D. kuriphilus. Five years after its introduction the exotic parasitoid T. sinensis established itself in the study sites and more than 25 morphospecies of native parasitoids emerged from D. kuriphilus galls
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