998 resultados para 289.272


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Este trabalho teve por objetivo a caracterização molecular de 13 acessos de Psidium spp. (Myrtaceae) identificados previamente quanto à reação ao nematoide da goiabeira. A extração do DNA das amostras foi executada conforme o protocolo de Shillito e Saul (1988). Os marcadores moleculares do tipo fAFLP, foram obtidos utilizando-se do 'fAFLP Regular Plant Genomes Fingerprinting Kit' (Applied Biosystems do Brasil Ltda.) onde foram testadas 24 combinações seletivas de primers, das quais 18 apresentaram amplificação que gerou 272 marcadores polimórficos. Para a análise dos marcadores, foram utilizados os softwares GeneScan (ABI Prism versão 1.0) e Genotyper (ABI Prism versão 1.03), e os dados coletados foram transformados em matriz binária que foi analisada no software PAUP (Phylogenetic Analysis Using Parcimony - versão 3.01). Foram também calculados índices de distância genética intra e interespecífica entre os materiais. Verificou-se que os marcadores AFLP foram eficientes na discriminação dos acessos entre si, bem como apontou similaridade genética entre os acessos identificados como resistentes ao nematoide Meloidogyne enterolobii, característica esta passível de exploração no futuro.

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AIMS AND BACKGROUND: The standard treatment of anal canal cancer (ACC) is combined chemotherapy and radiation therapy (RT), which is complex because of the shape of the target volumes and the need to minimize the irradiation of normal pelvic structures. In this study we compared the dosimetric results of helical tomotherapy (HT) plans with traditional 3D conformal RT (3DRT) plans for the treatment of ACC. METHODS AND STUDY DESIGN: Twelve patients (median age 57 years, range 38-83; F/M 8/4) treated with HT and concurrent chemotherapy for locally advanced ACC were selected. All had histologically confirmed squamous-cell carcinoma. A clinical target volume including the tumor and pelvic and inguinal lymph nodes was treated with HT to a total dose of 36 Gy in 1.8-Gy daily fractions. Then a sequential boost of 23.4 Gy in 1.8-Gy daily fractions (total dose 59.4 Gy) was delivered to the tumor and involved nodes. For all 12 patients, 3DRT plans were generated for comparison. Treatment plans were evaluated by means of standard dose-volume histograms. Dose coverage of the planning target volumes (PTVs), homogeneity index (HI), and mean doses to organs at risk (OARs) were compared. RESULTS: The coverage of PTV was comparable between the two treatment plans. HI was better in the HT vs. 3DRT plans (1.25 and 3.57, respectively; p<0.0001). HT plans resulted in better sparing of OARs (p<0.0001). CONCLUSIONS: HT showed superior target dose conformality and significant sparing of pelvic structures compared with 3DRT. Further investigation should determine if these dosimetric improvements will improve clinical outcomes regarding locoregional control, survival, and treatment-related acute and late morbidity.

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Existe una multiplicidad de factores que pueden afectar el riego del consumo de tabaco en la adolescencia. Mediante el análisis de estos factores de manera conjunta podemos desentrañar la relevancia específica que cada uno de ellos tiene en la conformación de la conducta individual de los adolescentes. El objetivo de esta investigación es profundizar en el conocimiento sobre la relación entre el consumo de tabaco en la adolescencia y variables socio-demográficas y socio-emocionales. Contamos con una muestra representativa de 2.289 adolescentes catalanes (15-18 años) que participaron en el Panel de Familias e Infancia. Se han realizado modelos de regresión para determinar la asociación estadística de los diferentes estados de ánimo (tristeza, nerviosismo y soledad), características del grupo de iguales y estilos parentales, con el consumo de tabaco. Los resultados indican que el comportamiento adictivo es más probable cuando los adolescentes muestran estados de ánimo negativos, controlando por variables socio-demográficas y otros factores de riesgo. Entre estos factores adicionales, los estilos parentales autoritativos reducen el riesgo del consumo de tabaco en comparación con la parentalidad autoritaria, permisiva y negligente. El consumo generalizado de tabaco en el grupo de iguales es el factor de riesgo que tiene una asociación más alta con el comportamiento individual del adolescente.

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Adult and pediatric laryngotracheal stenoses (LTS) comprise a wide array of various conditions that require precise preoperative assessment and classification to improve comparison of different therapeutic modalities in a matched series of patients. This consensus paper of the European Laryngological Society proposes a five-step endoscopic airway assessment and a standardized reporting system to better differentiate fresh, incipient from mature, cicatricial LTSs, simple one-level from complex multilevel LTSs and finally "healthy" from "severely morbid" patients. The proposed scoring system, which integrates all of these parameters, may be used to help define different groups of LTS patients, choose the best treatment modality for each individual patient and assess distinct post-treatment outcomes accordingly.

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Severe type III laryngomalacia LM is represented by a retroflexed epiglottis that touches the posterior pharyngeal wall and obstructs the laryngeal inlet. Endoscopic epiglottopexy is advised in such cases wherein pexy sutures are passed between the epiglottis and base of tongue. Using conventional needle carriers, it is difficult to pass such sutures that go deep enough into the tongue base. Such a pexy is prone to a break down. We describe a novel technique of placing these glossoepiglottic sutures using the Lichtenberger's needle carrier. We used this technique in three patients with excellent results and report no complications. We propose to use this technique in cases of epiglottic prolapse seen in severe LM and certain hypotonic conditions.

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The RFLP/PCR approach (restriction fragment length polymorphism/polymerase chain reaction) to genotypic mutation analysis described here measures mutations in restriction recognition sequences. Wild-type DNA is restricted before the resistant, mutated sequences are amplified by PCR and cloned. We tested the capacity of this experimental design to isolate a few copies of a mutated sequence of the human c-Ha-ras1 gene from a large excess of wild-type DNA. For this purpose we constructed a 272 bp fragment with 2 mutations in the PvuII recognition sequence 1727-1732 and studied the rescue by RFLP/PCR of a few copies of this 'PvuII mutant standard'. Following amplification with Taq-polymerase and cloning into lambda gt10, plaques containing wild-type sequence, PvuII mutant standard or Taq-polymerase induced bp changes were quantitated by hybridization with specific oligonucleotide probes. Our results indicate that 10 PvuII mutant standard copies can be rescued from 10(8) to 10(9) wild-type sequences. Taq polymerase errors originating from unrestricted, residual wild-type DNA were sequence dependent and consisted mostly of transversions originating at G.C bp. In contrast to a doubly mutated 'standard' the capacity to rescue single bp mutations by RFLP/PCR is limited by Taq-polymerase errors. Therefore, we assessed the capacity of our protocol to isolate a G to T transversion mutation at base pair 1698 of the MspI-site 1695-1698 of the c-Ha-ras1 gene from excess wild-type ras1 DNA. We found that 100 copies of the mutated ras1 fragment could be readily rescued from 10(8) copies of wild-type DNA.

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OBJECTIVES: To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING: We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS: Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION: Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.

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Inducible nitric oxide synthase (iNOS) functions as a homodimer. In cell extracts, iNOS molecules partition both in cytosolic and particulate fractions, indicating that iNOS exists as soluble and membrane associated forms. In this study, iNOS features were investigated in human intestinal epithelial cells stimulated with cytokines and in duodenum from mice exposed to flagellin. Our experiments indicate that iNOS is mainly associated with the particulate fraction of cell extracts. Confocal microscopy showed a preferential localization of iNOS at the apical pole of intestinal epithelial cells. In particulate fractions, iNOS dimers were more abundant than in the cytosolic fraction. Similar observations were seen in mouse duodenum samples. These results suggest that, in epithelial cells, iNOS activity is regulated by localization-dependent processes.

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Worldwide, about half the adult population is considered overweight as defined by a body mass index (BMI - calculated by body weight divided by height squared) ratio in excess of 25 kg.m-2. Of these individuals, half are clinically obese (with a BMI in excess of 30) and these numbers are still increasing, notably in developing countries such as those of the Middle East region. Obesity is a disorder characterised by increased mass of adipose tissue (excessive fat accumulation) that is the result of a systemic imbalance between food intake and energy expenditure. Although factors such as family history, sedentary lifestyle, urbanisation, income and family diet patterns determine obesity prevalence, the main underlying causes are poor knowledge about food choice and lack of physical activity3. Current obesity treatments include dietary restriction, pharmacological interventions and ultimately, bariatric surgery. The beneficial effects of physical activity on weight loss through increased energy expenditure and appetite modulation are also firmly established. Another viable option to induce a negative energy balance, is to incorporate hypoxia per se or combine it with exercise in an individual's daily schedule. This article will present recent evidence suggesting that combining hypoxic exposure and exercise training might provide a cost-effective strategy for reducing body weight and improving cardio-metabolic health in obese individuals. The efficacy of this approach is further reinforced by epidemiological studies using large-scale databases, which evidence a negative relationship between altitude of habitation and obesity. In the United States, for instance, obesity prevalence is inversely associated with altitude of residence and urbanisation, after adjusting for temperature, diet, physical activity, smoking and demographic factors.

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Tutkimus selvittää, mitä on jälkirealismi yhteiskunnallisen realismin muunnoksena ja mitkä ovat sen ”mimeettisen sopimuksen” ehdot eli todellisuutta ja sen ”jäljittelyä” koskevat perusteet. Teoreettiseen tarkasteluun yhdistyy Salaman romaanien analyysi suomalaisen jälkirealismin keskeisinä esimerkkeinä. Analysoidut teokset ovat Siinä näkijä missä tekijä (1972) sekä viisiosainen Finlandia-sarja, joka koostuu romaaneista Kosti Herhiläisen perunkirjoitus (1976), Kolera on raju bändi (1977), Pasi Harvalan tarina I (1981) ja II (1983) sekä Kaivo kellarissa (1983). Jälkirealismi määrittyy sellaiseksi kotimaisen kirjallisuuden trendiksi, joka muotoutuu 1900-luvun lopulla – samoihin aikoihin, kun yhteiskunnallinen todellisuus itsessään alkoi jälki- eli ”postmodernisoitua” ja kirjallinen postmodernismi maailmalla kehkeytyi. Toisin kuin postmodernismi, jälkirealismi muotoutuu (nimensä mukaan) realismin tradition pohjalta eikä pyri hylkäämään mimesistä. Mutta se ei enää allekirjoita aikaisemman realismin mimeettistä sopimusta sellaisenaan, vaan muokkaa ja ajanmukaistaa sopimusehtoja siksi, että yhteiskunnallinen todellisuus itsessään on rajussa muutoksessa eivätkä vanhat keinot enää yksin riitä sen todenmukaiseen kuvaamiseen. Salaman romaaneihin sisältyy jälkirealismin sopimusehdotelma, uudistus, jota Pertti Karkama on jo suuntaa-antavasti esitellyt, mutta jonka pääehdot vasta tämä tutkimus tarkemmin määrittelee. Jälkirealistinen sopimusuudistus koskee ensinnäkin kertojan asemaa (luku 2) ja luotettavuuden ehtoa (luku 3). Salaman vaihtuvat minä- ja hän-kertojat kyseenalaistavat yksioikoisen objektiivisuuden vaatimuksen ja irtautuvat ehdosta, että realistisen teoksen tulisi hahmottaa "kokonaisuus”. Kerrontarakenteen hierarkkinen malli murtuu ja ”kaikkitietävän” kertojan idea parodioituu. Kertojien suhdetta kuvaamaansa todellisuuteen ja muihin kertojiin/henkilöihin alkaa yhä enemmän määrittää intersubjektiivisuus, relationalisuus ja prosessuaalisuus. Myös luotettavuus kyseenalaistuu sekä temaattisena että rakennetta koskevana kysymyksenä. Jälkirealismi sallii kertojilleen yhä enemmän epäluotettavuutta tiedollisessa mutta erityisesti eettisessä mielessä. Toiseksi, jälkirealistinen sopimusuudistus koskee mimeettistä järjestystä, tarinan ja juonen kysymyksiä (luku 4). Mimeettisen järjestyksen, jonka on ajateltu toteutuvan realismin (enemmän tai vähemmän aristoteelisessa) juonessa, alkaa jälkirealismissa muuttua avoimeksi juonellistamiseksi. Itse kertomistoiminnan "jäljittely" tulee osaksi tarinaa. Ajatus siitä, että todellisuus on aina ennen sen mimesistä, kumoutuu. Kyse on paljolti metafiktiivisten piirteiden tunkeutumisesta myös realismiin, mutta metafiktio ei saa radikaalin postmodernistisia muotoja. Kolmanneksi jälkirealistinen sopimusuudistus koskee henkilökuvausta (luku 5). Siinä kyseenalaistuu realismille vanhastaan asetettu tyypillisyyden vaatimus. Henkilöhahmot eivät ole enää tietyn yhteiskuntaluokan esimerkillisiä edustajia vaan heissä ilmenee yhteiskunnallisen postmodernisoitumisen prosessi. Henkilöhahmot rakentuvat silti sellaisten tekstuaalis-kulttuuristen koodien varaan, jotka merkitsevät niiden lukemista "ihmisinä". Perinteisiä mimeettisiä koodeja ei rikota, kuten yleensä postmodernismissa, vaan ne painottuvat uudella tavalla. Todellisuuden muutoksen myötä myös ihmisten ja ihmiskäsitysten huomataan muuttuvan. Neljänneksi sopimusuudistus koskee referentiaalisuutta (luku 6) eli kielen todellisuus-kytköstä. Teoksissa käytetty kieli paljastaa erheelliseksi sen oletuksen, että realismin kielen – tai kielen ylipäänsä – ensisijainen tehtävä olisi viitata suoraan todellisuuteen. Jälkirealismi ei ”häivytä kielellisyyttään” vaan pikemminkin osoittaa todeksi sen bahtinilaisen ajatuksen, että kieli muodostaa monisuuntaisen ja dialogisen kehikon. Referenssi toimii tuon kehikon sisällä yhtenä kielen orientaationa, ”tahtona referenssiin”. Silti avoin dialogismi itsessään voi jopa vahvistaa referenssi-orientaatiota. Tutkimus on ensimmäinen Hannu Salaman tuotantoa tarkasteleva kirjallisuudentutkimuksen väitöskirja. Samalla se osallistuu kirjallisuustieteelliseen keskusteluun siitä, miten realismi ja mimesis tulisi meidän aikanamme ymmärtää.

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OBJETIVO: Avaliar índices de pulsatilidade das artérias umbilical (IPAU) e cerebral média (IPACM) e relação do índice de pulsatilidade umbilico-cerebral (IPAU/IPACM) em fetos de gestantes hipertensas e presença de resultados perinatais adversos. MATERIAIS E MÉTODOS: Analisamos IPAU, IPACM e IPAU/IPACM de 289 fetos de gestantes hipertensas quanto à previsão dos resultados perinatais adversos. Os resultados foram comparados sem e com ajuste pela idade gestacional. RESULTADOS: O índice de Apgar < 7 no 5º minuto foi associado com resultados alterados após o ajuste por idade gestacional. O risco para recém-nascidos pequenos para a idade gestacional aumentou em três vezes após o ajuste, com significância estatística em todos os parâmetros do Doppler. Na síndrome da hipóxia neonatal o aumento do risco ajustado pela idade gestacional foi estatisticamente significante no IPAU e IPAU/IPACM. Não houve aumento no risco de síndrome do desconforto respiratório na análise ajustada. A mortalidade perinatal e o IPAU alterado apresentaram um risco três vezes maior e foram estatisticamente significantes após o ajuste. CONCLUSÃO: Em gestantes hipertensas, o IPAU apresentou melhor correlação com os resultados perinatais do que o IPACM ou relação IPAU/IPACM. O risco de resultados adversos deve considerar a idade gestacional.

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This article examines how Samuelson defined his own role as an economist as a technical expert, who walked what he called the "middle of the road" to-seemingly-stay out of the realm of politics. As point of entry I discuss the highly tempting offers made by Theodore M. Schultz in the 1940s to come over to Chicago, which Schultz persistently repeated over three years and despite strong Chicago faculty resistance. A contrast between Schultz's own experiences as an economic expert at Iowa State, Samuelson's work as an external consultant for the National Resources Planning Board during the Second World War, and the firm support of the MIT administration for Samuelson's research serves to pinpoint the meaning of being technical for Samuelson, and the relation of the technical economic expert to the realm of politics.

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