979 resultados para teaching techniques


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The use of laparoscopic surgery has increased rapidly. However, a technically feasible procedure is not automatically recommendable. Thus, if cholecystectomy and fundoplication are currently fully validated techniques, this does not hold true for gastroplasty and kidney harvesting for transplantation: these operations are feasible indeed but their efficacy remains to be proved. Laparoscopic oncology has been shown to be feasible too, but its efficacy has not been documented yet.

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Ethmoidal regions weer prepared and dissected to demonstrate regional sinus anatomy and endoscopic surgery approaches from six human heads. After perparation, the specimens were plastinated using the standard S10 technique. A CT-scan of each ethmoidal block was performed before and after preparation of the block to access shrinkage. The plastinated specimens were successfully introduced into clinical teaching of sinus anatomy and surgery. One advantage of using these specimens is their long-lasting preservation without deterioration of the tissue. The specimens were well suited for comparative radiographic and ondoscopic studies, and the CT-scans allowed an exact measurement of tissue shrinkage due to plastination. Increaseed tissue rigidity and shrionkage due to plastination has to be taken into account for subsequent endoscopic observation.

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Teaching community medicine represents a significant challenge for medical schools, which tend to struggle to promote interest in the issue among students. In 2009, the Lausanne medical school introduced a "community immersion" module specifically designed to address the issue. The new module requires students working in small groups under the supervision of a tutor to investigate a health question of their choice. The investigation involves conducting interviews with stakeholders (health professionals, patients, politicians, etc.), carrying out a survey, and presenting the results of the investigation in a "congress". An external evaluation showed that the objectives of the initiative had been largely achieved, with an increase of interest in community medicine for over 50% of students (based on a total cohort of 150 students) and a high level of satisfaction for over 90% of students and tutors. This paper presents the results of the initiative and its use for promoting community-oriented medicine.

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Selostus: Kolme viljojen mekaanista rikkakasvintorjuntamentelmää

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Intraarterial procedures such as chemoembolization and radioembolization aim for the palliative treatment of advanced hepatocellular carcinoma (stage BCLC B and C with tumoral portal thrombosis). The combination of hepatic intraarterial chemotherapy and systemic chemotherapy can increase the probability of curing colorectal cancer with hepatic metastases not immediately accessible to surgical treatment or percutaneous ablation.

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Infektiivinen endokardiitti yliopistollisessa keskussairaalassa vuosina 1980-2004 hoidetuilla aikuispotilailla Tausta: Infektiivinen endokardiitti on edelleen vakava sairaus. Huolimatta siitä, että taudin diagnostiikka ja hoito ovat kehittyneet, siihen liittyy edelleen merkittävää sairastuvuutta ja kuolleisuutta. Endokardiitin taudinkuvassa on viime vuosina tapahtunut muutoksia monissa maissa. Tavoitteet: Tutkia endokardiitin kliinista kuvaa ja ennustetta suomalaisessa yliopistosairaalassa vuosina 1980-2004 endokardiitin vuoksi hoidetuilla aikuispotilailla. Aineisto: Osatyössä I endokardiitin todennäköisyyttä analysoitiin 222:lla vuosina 1980-1995 endokardiittiepäilyn vuoksi hoidetulla potilaalla käyttäen apuna sekä Duken että von Reyn diagnostisia kriteereitä. Osatyössä II tutkittiin endokardiittiin liittyviä neurologisia komplikaatioita 218 varmassa tai mahdollisessa endokardiittiepisodissa. Osatyössä III tutkittiin seerumin C-reaktiivisen proteiinin (CRP) käyttökelpoisuutta hoitovasteen arvioinnissa 134:ssä varmaksi luokitellussa endokardiittiepisodissa. Osatyössä IV tutkittiin yleisbakteeri-PCRmenetelmän käyttökelpoisuutta etiologisessa diagnostiikassa 56:lla endokardiittiepäilyn vuoksi leikatulla potilaalla. Osatöissä V ja VI analysoitiin kaikki vuosina 1980-2004 hoidetut 303 endokardiittipotilasta lyhytaikais- ja 1-vuotisennusteen suhteen sekä tutkittiin endokardiitin taudinkuvassa tapahtuneita muutoksia sairaalassamme. Tulokset: Duken kriteerit osoittautuivat von Reyn kriteereitä herkemmiksi endokardiitin diagnostiikassa: 243 tutkitusta episodista 114 luokiteltiin varmoiksi endokardiiteiksi Duken kriteereillä, kun vastaavasti ainoastaan 64 luoteltiin varmoiksi von Reyn kriteereillä (p<0.001). Lisäksi peräti 115 episodissa endokardiitin diagnoosi hylättiin von Reyn kriteereillä, kun diagnoosi hylättiin Duken kriteereillä ainoastaan 37 episodissa (p<0.001). Neurologinen komplikaatio ilmeni ennen mikrobilääkehoidon aloittamista 76 %:ssa episodeja ollen ensimmäinen oire 47 %:ssa. Kuolema oli merkitsevästi yhteydessä neurologisiin komplikaatioihin. Hoitovastetta seurattaessa seerumin CRP:n lasku oli merkitsevästi nopeampaa komplikaatioitta toipuvilla potilailla kuin niillä, joille kehittyi komplikaatioita tai jotka menehtyivät tautiinsa. PCR-tutkimus poistetusta läpästä antoi ainoana menetelmänä etiologisen diagnoosin neljässä tapauksessa (2 stafylokokkilajia, 1 Streptococcus bovis,1 Bartonella quintana), joissa kaikissa mikrobilääkehoito oli ollut käytössä ennen näytteiden ottamista. Koko aineistossa kahden läpän infektio tai neurologisten komplikaatioiden, perifeeristen embolioiden tai sydämen vajaatoiminnan kehittyminen ennustivat sekä sairaalakuolleisuutta että 1-vuotiskuolleisuutta, kun taas ≥65 vuoden ikä ja sydämen ultraäänitutkimuksessa todettu vegetaatio tai Duken luokittelun mukainen pääkriteeri ennustivat kuolemaa vuoden sisällä. Korkea CRP-taso sairaalaan tullessa ennusti sekä sairaalakuolleisuutta että 1-vuotiskuolleisuutta. Huumeiden käyttäjien endokardiitit lisääntyivät tutkimusaikana merkitsevästi (p<0.001). Päätelmät: Tässä työssä vahvistetaan Duken kriteerien käyttökelpoisuus endokardiitin diagnostiikassa. Lisäksi vahvistui käsitys, että nopea diagnoosi ja mikrobilääkehoidon aloittaminen ovat parhaat keinot ehkäistä neurologisia komplikaatioita ja parantaa endokardiittipotilaiden ennustetta. CRP:n normalisoituminen on endokardiittipotilailla hyvän ennusteen merkki. Suoraan läppäkudoksesta tehty PCR-tutkimus on hyödyllinen, kun taudin aiheuttaja on kasvuominaisuuksiltaan vaativa tai potilas on saanut mikrobilääkehoitoa ennen viljelynäytteiden ottamista. Muutamat aiemmissa tutkimuksissa todetut huonon ennusteen merkit ennustavat huonoa ennustetta myös tämän tutkimuksen potilailla. Uutena löydöksenä ilmeni, että korkea CRP-arvo sairaalaan tullessa merkitsee sekä huonoa lyhyt- että pitkäaikaisennustetta. Huumeiden käyttäjien endokardiittien ilmaantuminen on tärkein epidemiologinen muutos 25 vuoden tutkimusaikana.

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Many researchers have concluded that secondary or delayed ettringite is responsible for serious premature deterioration of concrete highways. In some poorly performing Iowa concretes, ettringite is the most common secondary mineral but its role in premature deterioration is uncertain since some researchers still maintain that secondary ettringite does not itself cause deterioration. The current research project was designed to determine experimentally if it is possible to reduce secondary ettringite formation in concrete by treating the concrete with commercial crystallization inhibitor chemicals. The hypothesis is such that if the amount of ettringite is reduced, there will also be a concomitant reduction of concrete expansion and cracking. If both ettringite formation and deterioration are simultaneously reduced, then the case for ettringite induced expansion/cracking is strengthened. The experiment used four commercial inhibitors - two phosphonates, a polyacrylic acid, and a phosphate ester. Concrete blocks were subjected to continuous immersion, wet/dry and freeze/thaw cycling in sodium sulfate solutions and in sulfate solutions containing an inhibitor. The two phosphonate inhibitors, Dequest 2060 and Dequest 2010, manufactured by Monsanto Co., were effective in reducing ettringite nucleation and growth in concrete. Two other inhibitors, Good-rite K752 and Wayhib S were somewhat effective, but less so than the two phosphonates. Rapid experiments with solution growth inhibition of ettringite without the presence of concrete phases were used to explore the mechanisms of inhibition of this mineral. Reduction of new ettringite formation in concrete blocks also reduced expansion and cracking of the blocks. This relationship clearly links concrete expansion with this mineral - a conclusion that some research workers have disputed despite theoretical arguments for such a relationship and despite numerous observations of ettringite mineralization in prematurely deteriorated concrete highways. Secondary ettringite nucleation and growth must cause concrete expansion because the only known effect of the inhibitor chemicals is to reduce crystal nucleation and growth, and the inhibitors cannot in any other way be responsible for the reduction in expansion. The mechanism of operation of the inhibitors on ettringite reduction is not entirely clear but the solution growth experiments show that they prevent crystallization of a soluble ettringite precursor gel. The present study shows that ettringite growth alone is not responsible for expansion cracking because the experiments showed that most expansion occurs under wet/dry cycling, less under freeze/thaw cycling, and least under continuous soaking conditions. It was concluded from the different amounts of damage that water absorption by newly-formed, minute ettringite crystals is responsible for part of the observed expansion under wet/dry conditions, and that reduction of freeze resistance by ettringite filling of air-entrainment voids is also important in freeze/thaw environments.

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This research was initiated in 1991 as a part of a whitetopping project to study the effectiveness of various techniques to enhance bond strength between a new portland cement concrete (PCC) overlay and an existing asphalt cement concrete (ACC) pavement surface. A 1,676 m (5,500 ft) section of county road R16 in Dallas County was divided into 12 test sections. The various techniques used to enhance bond were power brooming, power brooming with air blast, milling, cement and water grout, and emulsion tack coat. Also, two sections were planed to a uniform cross-section, two pavement thicknesses were placed, and two different concrete mix proportions were used. Bond strength was perceived to be the key to determining an appropriate design procedure for whitetopping. If adequate bond is achieved, a bonded PCC overlay technique can be used for design. Otherwise, an unbonded overlay procedure may be more appropriate. Conclusions are as follows: (1) Bond Strength Differences - Milling increased bond strength versus no milling. Tack coat showed increased bond strength versus no tack coat. Planing, Air Blast and Grouting did not provide noticeable improvements in bond strength; nor did different PCC types or thicknesses affect bond strength significantly. (2) Structure - Structural measurements correlated strongly with the wide variation in pavement thicknesses. They did not provide enough information to determine the strength of bonding or the level of support being provided by the ACC layer. Longitudinal cracking correlated with PCC thicknesses and with planing. (3) Bond Over Time - The bond between PCC and ACC layers is degrading over time in the outside wheel path in all of the sections except tack coat (section 12). The bond strength in the section with tack coat was lower than the others, but remained relatively steady.

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En la investigació de la complexació de metalls mitjançant eines electroanalítiques són emprades dues aproximacions generals. La primera, anomenada de modelatge dur (hardmodelling), es basa en la formulació d'un model fisicoquímic conjunt per als processos electròdic i de complexació i en la resolució analítica o numèrica del model. Posteriorment, l'ajust dels paràmetres del model a les dades experimentals donarà la informació desitjada sobre el procés de complexació. La segona aproximació, anomenada de modelatge tou (soft-modelling), es basa en la identificació d'un model de complexació a partir de l'anàlisi numèrica i estadística de les dades, sense cap assumpció prèvia d'un model. Aquesta aproximació, que ha estat extensivament emprada amb dades espectroscòpiques, ho ha estat poquíssim amb dades electroquímiques. En aquest article tractem de la formulació d'un model (hard-modelling) per a la complexació de metalls en sistemes amb mescles de lligands, incloent-hi lligands macromoleculars, i de l'aplicació d

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The aim of this study was to review our experience in percutaneous endoscopic gastrostomy (PEG) performed in patients with cancer of the upper aerodigestive tract. Descriptive retrospective study of 142 patients (115 males, 27 females), mean age 62.4 years (25-84 years), with head and neck or esophageal cancer, who underwent PEG tube insertion between January 2006 and December 2008. The studied parameters were indications, success rate, rate and type of complications, and their management. Percutaneous endoscopic gastrostomy was inserted before chemoradiation therapy in 80% and during or after cancer treatment in 20% of the patients. PEG placement was possible in 137 patients (96%). Major complications were observed in 9 (7%) and minor complications in 22 (17%) of the 137 patients. Seven of the 9 patients with a major complication needed revision surgery. The mortality directly related to the procedure was 0.7%. Percutaneous endoscopic gastrostomy tube insertion has a high success rate. In patients with upper aerodigestive tract cancer, PEG should be the first choice for enteral nutrition when sufficient oral intake is not possible. Although apparently easy, the procedure may occasionally lead to severe complications. Therefore, a strict technique and knowledge of clinical signs of possible complications are mandatory.

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If single case experimental designs are to be used to establish guidelines for evidence-based interventions in clinical and educational settings, numerical values that reflect treatment effect sizes are required. The present study compares four recently developed procedures for quantifying the magnitude of intervention effect using data with known characteristics. Monte Carlo methods were used to generate AB designs data with potential confounding variables (serial dependence, linear and curvilinear trend, and heteroscedasticity between phases) and two types of treatment effect (level and slope change). The results suggest that data features are important for choosing the appropriate procedure and, thus, inspecting the graphed data visually is a necessary initial stage. In the presence of serial dependence or a change in data variability, the Nonoverlap of All Pairs (NAP) and the Slope and Level Change (SLC) were the only techniques of the four examined that performed adequately. Introducing a data correction step in NAP renders it unaffected by linear trend, as is also the case for the Percentage of Nonoverlapping Corrected Data and SLC. The performance of these techniques indicates that professionals" judgments concerning treatment effectiveness can be readily complemented by both visual and statistical analyses. A flowchart to guide selection of techniques according to the data characteristics identified by visual inspection is provided.