955 resultados para iq motive
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RATIONALE AND OBJECTIVES: Dose reduction may compromise patients because of a decrease of image quality. Therefore, the amount of dose savings in new dose-reduction techniques needs to be thoroughly assessed. To avoid repeated studies in one patient, chest computed tomography (CT) scans with different dose levels were performed in corpses comparing model-based iterative reconstruction (MBIR) as a tool to enhance image quality with current standard full-dose imaging. MATERIALS AND METHODS: Twenty-five human cadavers were scanned (CT HD750) after contrast medium injection at different, decreasing dose levels D0-D5 and respectively reconstructed with MBIR. The data at full-dose level, D0, have been additionally reconstructed with standard adaptive statistical iterative reconstruction (ASIR), which represented the full-dose baseline reference (FDBR). Two radiologists independently compared image quality (IQ) in 3-mm multiplanar reformations for soft-tissue evaluation of D0-D5 to FDBR (-2, diagnostically inferior; -1, inferior; 0, equal; +1, superior; and +2, diagnostically superior). For statistical analysis, the intraclass correlation coefficient (ICC) and the Wilcoxon test were used. RESULTS: Mean CT dose index values (mGy) were as follows: D0/FDBR = 10.1 ± 1.7, D1 = 6.2 ± 2.8, D2 = 5.7 ± 2.7, D3 = 3.5 ± 1.9, D4 = 1.8 ± 1.0, and D5 = 0.9 ± 0.5. Mean IQ ratings were as follows: D0 = +1.8 ± 0.2, D1 = +1.5 ± 0.3, D2 = +1.1 ± 0.3, D3 = +0.7 ± 0.5, D4 = +0.1 ± 0.5, and D5 = -1.2 ± 0.5. All values demonstrated a significant difference to baseline (P < .05), except mean IQ for D4 (P = .61). ICC was 0.91. CONCLUSIONS: Compared to ASIR, MBIR allowed for a significant dose reduction of 82% without impairment of IQ. This resulted in a calculated mean effective dose below 1 mSv.
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BACKGROUND: During stress, vasopressin is a potent synergistic factor of CRH as a hypothalamic stimulator of the HPA axis. The measurements of CRH and vasopressin levels are cumbersome because of their instability and short half-life. Copeptin is a more stable peptide stoichiometrically released from the same precursor molecule. The aim of our study was to compare copeptin and cortisol levels in different stress situations. METHODS: Three groups of patients with increasing stress levels were investigated: a) healthy controls without apparent stress (n=20), b) hospitalized medical patients with moderate stress (n=25) and c) surgical patients 30 minutes after extubation, with maximal stress (n=29). In all patients we assessed cortisol and copeptin levels. Copeptin levels were measured with a new sandwich immunoassay. RESULTS: Cortisol levels in controls were (median, IQ range, 486 [397-588] nmol/L), not significantly different as compared to medical patients (438 [371-612] nmol/L, p=0.69). Cortisol levels in surgical patients after extubation were higher (744 [645-1062] nmol/L p<0.01 vs controls and medical patients). Copeptin levels in controls were 4.3 [3.2-5.5] pmol/L, which was lower as compared to medical patients (17.5 [6.4-24.1], p<0.001) and surgical patients after extubation (67.5 [37.8-110.0] pmol/L, p<0.001). The correlation between copeptin levels and cortisol was r=0.46, p<0.001. CONCLUSION: Copeptin is a novel marker of the individual stress level. It more subtly mirrors moderate stress as compared to cortisol values.
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Current evidence on the association between personality factors, drinking motives, and alcohol use comes exclusively from North America. The present study, however, is based on a sample of 2090 Swiss college students (mean age 23.5, SD = 2,9) and investigates by means of structural equation modeling whether drinking motives mediate the association between personality factors and alcohol use. The results revealed that extraversion was positively related to drinking for enhancement motives; conscientiousness was negatively related to both enhancement and coping motives; and neuroticism was positively related to drinking for coping motives. The association between extraversion and alcohol use was mediated by enhancement motives, while the negative association between conscientiousness and alcohol use was partially mediated by both enhancement and coping motives. This concurs with the findings of North American studies. However, in contrast to these findings, our study finds that coping motives attenuate the "protective" effect of neuroticism with regard to alcohol use. Taken together, the study indicates that alcohol use serves specific purposes depending on particular personality traits. The finding that personality-related effects are partially mediated by motives increases the likelihood that motive-based preventive efforts will help reduce alcohol use among young adults who display particular personality traits.
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The current study conceptualized observer reactions to uncivil behavior towards women as an ethical behavior and examined three factors (target reaction, actor motive, and actor-target relationship) that influence these reactions. Two vignette studies with women and men undergraduate and graduate students in western Switzerland were conducted. Study 1 (N=148) was a written vignette study that assessed how the reaction of female targets to incivility and the motives of actors influenced observer reactions. Results showed that a female target's reaction influenced observers' evaluations of the harm caused by an uncivil incident, and that an actor's motive affected observers' assessments of the necessity to intervene. Study 2 (N=81) was a video vignette study that assessed the effects of the reactions by female targets to incivility and the relationship between the target and the actor on observer reactions.We found that female targets' reactions influenced observers' evaluations of harm and the perceived necessity to intervene. Furthermore, the effect of a female target's reaction on observers' evaluations of harm was moderated by the relationship between the actor and the target: a female target who laughed at the uncivil behavior was perceived as less harmed, when she and the actor had a personal relationship than when they had a professional relationship. When the female target reacted hurt or neutrally, actor-target relationship did not affect observers' evaluations of harm. We conclude by discussing the implications of our findings for theory and practice.
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Antipsychotic medication represents the treatment of choice in psychosis according to clinical guidelines. Nevertheless, studies show that half to almost three-quarter of all patients discontinue medication with antipsychotics after some time, a fact which is traditionally ascribed to side-effects, mistrust against the clinician and poor illness insight. The present study investigated whether positive attitudes toward psychotic symptoms (ie, gain from illness) represent a further factor for medication noncompliance. An anonymous online survey was set up in order to prevent conservative response biases that likely emerge in a clinical setting. Following an iterative selection process, data from a total of 113 patients with a likely diagnosis of schizophrenia and a history of antipsychotic treatment were retained for the final analyses (80%). While side-effect profile and mistrust emerged as the most frequent reasons for drug discontinuation, 28% of the sample reported gain from illness (eg, missing voices, feeling of power) as a motive for noncompliance. At least every fourth patient reported the following reasons: stigma (31%), mistrust against the physician/therapist (31%), and rejection of medication in general (28%). Approximately every fifth patient had discontinued antipsychotic treatment because of forgetfulness. On average, patients provided 4 different explanations for noncompliance. Ambivalence toward symptoms and treatment should thoroughly be considered when planning treatment in psychosis. While antipsychotic medication represents the evidence-based cornerstone of the current treatment in schizophrenia, further research is needed on nonpharmacological interventions for noncompliant patients who are willing to undergo intervention but refuse pharmacotherapy.
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A boy with a right congenital hemiparesis due to a left pre-natal middle cerebral artery infarct developed focal epilepsy at 33 months and then an insidious and subsequently more rapid, massive cognitive and behavioural regression with a frontal syndrome between the ages of 4 and 5 years with continuous spike-waves during sleep (CSWS) on the EEG. Both the epilepsy and the CSWS were immediately suppressed by hemispherotomy at the age of 5 years and 4 months. A behavioural-cognitive follow-up prior to hemispherotomy, an per-operative EEG and corticography and serial post-operative neuropsychological assessments were performed until the age of 11 years. The spread of the epileptic activity to the "healthy" frontal region was the cause of the reversible frontal syndrome. A later gradual long-term but incomplete cognitive recovery, with moderate mental disability was documented. This outcome is probably explained by another facet of the epilepsy, namely the structural effects of prolonged epileptic discharges in rapidly developing cerebral networks which are, at the same time undergoing the reorganization imposed by a unilateral early hemispheric lesion. Group studies on the outcome of children before and after hemispherectomy using only single IQ measures, pre- and post-operatively, may miss particular epileptic cognitive dysfunctions as they are likely to be different from case to case. Such detailed and rarely available complementary clinical and EEG data obtained in a single case at different time periods in relation to the epilepsy, including per-operative electrophysiological findings, may help to understand the different cognitive deficits and recovery profiles and the limits of full cognitive recovery.
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Descripció de la intervenció duta a terme a l'IES Breamo de la Corunya, l'objectiu general de la qual era la prevenció de la violència escolar. Aquest objectiu es concreta en l'elaboració d'un protocol d'actuació de cara a la seva consecució: protocol d'actuació preventiva (primària), de detecció primerenca (secundària) i d'actuació pal·liativa (terciària).
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Rapport de synthèse : Cette thèse a étudié en détail le cas d'un enfant souffrant d'une hémiplégie congénitale sur un infarctus prénatal étendu qui a développé une forme particulière d'épilepsie, le syndrome des pointes ondes continues du sommeil (POCS), associé à une régression mentale massive. Les caractéristiques de cette détérioration pointaient vers un dysfonctionnement de type frontal. Une chirurgie de l'épilepsie (hémisphérotomie) a, non seulement, permis la guérison de l'épilepsie mais une récupération rapide sur le plan comportemental et cognitif, suivie d'une reprise plus lente du développement, avec finalement à l'âge de 11 ans un niveau de déficience intellectuelle modérée. L'intérêt de cette étude réside dans le fait que l'enfant a pu être suivi prospectivement entre l'âge de 4.5 ans et 11 ans par des enregistrements électro-encéphalographiques (EEG) ainsi que des tests neuropsychologiques et des questionnaires de comportements sériés, permettant de comparer les périodes pré-, péri- et postopératoires, ce qui est rarement réalisable. Un enregistrement EEG de surface a même pu être effectué durant l'opération sur l'hémisphère non lésé, permettant de documenter l'arrêt des décharges épileptiformes généralisées dès la fin de l'intervention. L'hypothèse que nous avons- souhaité démontrer est que la régression comportementale et cognitive présentée par l'enfant après une période de développement précoce presque normale (retard de langage) était de nature épileptique : nous l'expliquons par la propagation de l'activité électrique anormale à partir de la lésion de l'hémisphère gauche vers les régions préservées, en particulier frontales bilatérales. L'hémisphérotomie a permis une récupération rapide en déconnectant l'hémisphère gauche lésé et épileptogène de l'hémisphère sain, qui a ainsi pu reprendre les fonctions cognitives les plus importantes. Les progrès plus lents par la suite et l'absence de rattrapage au delà d'un niveau de déficience mentale modérée sont plus difficiles à expliquer: on postule ici un effet de l'épilepsie sur le développement de réseaux neuronaux de l'hémisphère initialement non lésé, réseaux qui sont à la fois à un stade précoce de leur maturation et en cours de réorganisation suite à la lésion prénatale. La littérature sur les déficits cognitifs avant et après hemisphérotomie s'est surtout préoccupée du langage et de sa récupération possible. À notre connaissance, notre étude est la première à documenter la réversibilité d'une détérioration mentale avec les caractéristiques d'un syndrome frontal après hémisphérotomie. La chirurgie de l'épilepsie a offert ici une occasion unique de documenter le rôle de l'activité épileptique dans la régression cognitive puisqu'en interrompant brusquement la propagation de l'activité électrique anormale, on a pu comparer la dynamique du développement avant et après l'intervention. La mise en relation des multiples examens cliniques et EEG pratiqués chez un seul enfant sur plusieurs années a permis d'obtenir des informations importantes dans la compréhension des troubles cognitifs et du comportement associés aux épilepsies focales réfractaires. ABSTRACT : A boy with a right congenital hemiparesis due to a left pre-natal middle cerebral artery infarct developed focal epilepsy at 33 months and then an insidious and subsequently more rapid, massive cognitive and behavioural regression with a frontal syndrome between the ages of 4 and 5 years with continuous spike-waves during sleep (CSWS) on the EEG. Both the epilepsy and the CSWS were immediately suppressed by hemispherotomy at the age of 5 years and 4months. A behavioural-cognitive follow-up prior to hemispheratomy, an per-operative EEG and corticography and serial post-operative neuropsychological assessments were performed until the age of 11 years. The spread of the epileptic activity to the "healthy" frontal region was the cause of the reversible frontal syndrome. A later gradual long-term but incomplete cognitive recovery, with moderate mental disability was documented. T9ris outcome is probably explained by another facet of the epilepsy, namely the structural effects of prolonged epileptic dischazges in rapidly developing cerebral networks which are, at the same time undergoing the reorganization imposed by a unilateral early hemispheric lesion. Group studies on the outcome of children before and after hemispherectomy using only single IQ measures, pre- and postoperatively, may miss particular epileptic cognitive dysfunctions as they are likely to be different from case to case. Such detailed and rarely available complementary clinical and EEG data obtained in a single case at different time periods in relation to the epilepsy, including peroperative electrophysiological findings, may help to understand the different cognitive deficits and recovery profiles and the limits of full cognitive recovery.
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Membrane transport of proton and calcium (Ca2+) plays a fundamental role in growth and developmental processes in higher plant cells. The plasma membrane contains an ATPase (P-ATPase) that pumps protons into the extracellular space, whereas two proton pumps, a vacuolar-type ATPase (V-ATPase) and a pyrophosphatase (H+-PPase) are associated with the tonoplast and pump protons into the vacuole. The P-ATPase, V-ATPase and H+-PPase catalyse electrogenic H+-translocation, giving rise to a proton motive force used to transport different molecules, via specific transport proteins (channels or carriers: H+-symport or H+-antiport), across the plasma membrane and the tonoplast
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E-2-chloro-8-methyl-3-[(4'-methoxy-1'-indanoyl)-2'-methyliden]-quinoline (IQ) is a new quinoline derivative which has been reported as a haemoglobin degradation and ß-haematin formation inhibitor. The haemoglobin proteolysis induced by Plasmodium parasites represents a source of amino acids and haeme, leading to oxidative stress in infected cells. In this paper, we evaluated oxidative status in Plasmodium berghei-infected erythrocytes in the presence of IQ using chloroquine (CQ) as a control. After haemolysis, superoxide dismutase (SOD), catalase, glutathione cycle and NADPH + H+-dependent dehydrogenase enzyme activities were investigated. Lipid peroxidation was also assayed to evaluate lipid damage. The results showed that the overall activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were significantly diminished by IQ (by 53.5% and 100%, respectively). Glutathione peroxidase activity was also lowered (31%) in conjunction with a higher GSSG/GSH ratio. As a compensatory response, overall SOD activity increased and lipid peroxidation decreased, protecting the cells from the haemolysis caused by the infection. CQ shared most of the effects showed by IQ; however it was able to inhibit the activity of isocitrate dehydrogenase and glutathione-S-transferase. In conclusion, IQ could be a candidate for further studies in malaria research interfering with the oxidative status in Plasmodium berghei infection.
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The Wechsler Intelligence Scale for Children-fourth edition (i.e. WISC-IV) recognizes a four-factor scoring structure in addition to the Full Scale IQ (FSIQ) score: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI) indices. However, several authors suggested that models based on the Cattell-Horn-Carroll (CHC) theory with 5 or 6 factors provided a better fit to the data than does the current four-factor solution. By comparing the current four-factor structure to CHC-based models, this research aimed to investigate the factorial structure and the constructs underlying the WISC-IV subtest scores with French-speaking Swiss children (N = 249). To deal with this goal, confirmatory factor analyses (CFAs) were conducted. Results showed that a CHC-based model with five factors better fitted the French-Swiss data than did the current WISC-IV scoring structure. All together, these results support the hypothesis of the appropriateness of the CHC model with French-speaking children.
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BACKGROUND This study was realized thanks to the collaboration of children and adolescents who had been resected from cerebellar tumors. The medulloblastoma group (CE+, n = 7) in addition to surgery received radiation and chemotherapy. The astrocytoma group (CE, n = 13) did not receive additional treatments. Each clinical group was compared in their executive functioning with a paired control group (n = 12). The performances of the clinical groups with respect to controls were compared considering the tumor's localization (vermis or hemisphere) and the affectation (or not) of the dentate nucleus. Executive variables were correlated with the age at surgery, the time between surgery-evaluation and the resected volume. METHODS The executive functioning was assessed by means of WCST, Complex Rey Figure, Controlled Oral Word Association Test (letter and animal categories), Digits span (WISC-R verbal scale) and Stroop test. These tests are very sensitive to dorsolateral PFC and/or to medial frontal cortex functions. The scores for the non-verbal Raven IQ were also obtained. Direct scores were corrected by age and transformed in standard scores using normative data. The neuropsychological evaluation was made at 3.25 (SD = 2.74) years from surgery in CE group and at 6.47 (SD = 2.77) in CE+ group. RESULTS The Medulloblastoma group showed severe executive deficit (= 1.5 SD below normal mean) in all assessed tests, the most severe occurring in vermal patients. The Astrocytoma group also showed executive deficits in digits span, semantic fluency (animal category) and moderate to slight deficit in Stroop (word and colour) tests. In the astrocytoma group, the tumor's localization and dentate affectation showed different profile and level of impairment: moderate to slight for vermal and hemispheric patients respectively. The resected volume, age at surgery and the time between surgery-evaluation correlated with some neuropsychological executive variables. CONCLUSION Results suggest a differential prefrontal-like deficit due to cerebellar lesions and/or cerebellar-frontal diaschisis, as indicate the results in astrocytoma group (without treatments), that also can be generated and/or increased by treatments in the medulloblastoma group. The need for differential rehabilitation strategies for specific clinical groups is remarked. The results are also discussed in the context of the Cerebellar Cognitive Affective Syndrome.
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RESUME INTRODUCTION Comprendre les déterminants de l'arrêt du tabagisme est un enjeu crucial, tant sur le plan clinique qu'en termes de santé publique. Dans l'étude transversale présentée ici, nous décrivons ce processus au travers de l'expérience d'ex-fumeurs. METHODE Sur une période de 4 mois, nous avons proposé à chaque patient consultant la Policlinique Médicale Universitaire de Lausanne de participer à une étude visant à examiner leur expérience de l'arrêt du tabagisme. Les critères d'inclusion étaient les suivants: (1) âge ≥ 18 ans (2) connaissance minimale de la langue française (capacité de comprendre et répondre aux questions) (3) être un ex-fumeur (défini comme une personne actuellement abstinente mais ayant fumé au moins 100 cigarettes [≥ 5 paquets] pendant > 6 mois dans le passé). Une infirmière formée a mené des entretiens semi-structurés en face-à-face avec les ex-fumeurs recrutés en utilisant un questionnaire explorant les 67 questions parmi les thèmes suivants : caractéristiques démographiques et socioéconomiques ; habitudes antérieures de consommation ; stades de motivation ; influence de l'environnement social ; état de santé et préoccupations au sujet de la santé ; perception des risques et des bénéfices du tabagisme ; perception de la dépendance nicotinique ; offre d'un counseling médical spécifique ; connaissances sur les modalités thérapeutiques disponibles et méthodes utilisées pour arrêter de fumer. Les résultats sont exprimés en nombres absolus, en pourcentages, en moyennes et en dispersion. RÉSULTATS 88 ex-fumeurs ont été inclus dans l'étude. Leurs caractéristiques démographiques et socioéconomiques sont les suivantes : La grande majorité d'entre eux sont des hommes (81%), l'âge moyen de 51 ans (variant de 19 à 81 ans), la moitié sont mariés, 72% de nationalité suisse et une grosse minorité (40%) ont une formation supérieure (universitaire ou équivalente). Leur histoire de consommation montre que l'âge moyen d'initiation du tabagisme est de 18 ans (entre 11 et 30 ans), et 23% ont commencé avant 16 ans. La consommation moyenne était de 26 cigarettes/jour. Presque tous les sujets (92%) étaient en contact fréquent avec des fumeurs à la maison, à l'école, au travail ou avec des amis au moment où ils ont commencé à fumer. La moitié des patients a essayé à une ou deux reprises d'arrêter de fumer avant de parvenir à une réelle abstinence. La durée depuis leur arrêt de consommation de cigarettes était en moyenne 5 ans et seuls 16% des sujets ont fumé occasionnellement depuis l'arrêt de leur consommation régulière. La majorité des ex-fumeurs (93%) dit avoir arrêté de manière abrupte et sans aucune aide thérapeutique (83%). 70 % des patients décrivent l'arrêt comme plutôt ou très difficile. Les problèmes décrits après l'interruption du tabagisme sont une prise pondérale (27%), la dépendance (23%), l'irritabilité (15%), les contacts avec des fumeurs (15%) et le manque de cigarette après les repas (11%). Les motivations principales à arrêter de fumer étaient des préoccupations générales au sujet de la santé (39%), des symptômes (23%) ou des signes cliniques spécifiques (22%), comme des problèmes cardiovasculaires ou respiratoires, ainsi que la conviction que le moment était venu d'arrêter (13%). D'autres motivations (comme les enfants, la grossesse, le coût...) étaient rarement mentionnées alors que 45% d'entre eux ont tout de même ressenti une pression de l'entourage, principalement de la part dé personnes vivant sous le même toit, de leurs famille ou amis. L'effet positif majeur de l'abstinence est, à leurs yeux, une amélioration globale de la santé (48%) ou de leurs problèmes cardiovasculaires ou respiratoires (32%). Trois quarts (74 %) des sujets savent que les cigarettes dites «légères »sont aussi nuisibles que les cigarettes normales, et 90 % sont conscients du fait que la nicotine peut induire une dépendance ; la moitié d'entre eux ne réalisent toutefois pas que le filtre ne protège pas contre les dangers de l'inhalation de fumée. Prés de trois quarts (73%) des ex-fumeurs disent avoir été interrogés sur leur consommation de tabac à l'occasion d'une consultation médicale motivée par un problème de santé et 30% clairement encouragés à arrêter par leur médecin. A ce sujet, 78 % sont d'avis qu'un médecin devrait par principe conseiller un arrêt du tabac. CONCLUSION Les 88 ex-fumeurs de cet échantillon ont, pour la plupart, arrêté la cigarette par leurs propres moyens, après un ou plusieurs échecs. Leurs motivations principales étaient le souci de leur propre santé, globalement ou relativement à des symptômes ou des signes cliniques spécifiques, ce qui reflète le fait que les patients sont relativement bien informés des dangers liés à la consommation de tabac. Enfin, le fumeur est sensible à l'influence de son environnement social, et, dans cette perspective, l'abstinence devrait être encouragée par les autorités sanitaires, les professionnels de la santé et les autres membres de la communauté.
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An association between severe iodine deficiency and poor mental development has been found in many studies. We examined the relationship between moderate or mild iodine deficiency and intellectual capacity in order to determine whether problems common to severe iodine deficiency (including mental retardation) also emerge in a more subtle form. We also wished to know whether the classic methodology (comparing iodine-deficient zones with nondeficient zones) is the most adequate, and propose to combine this grouping by zones with urinary iodine presented by individuals in each zone. We measured IQ, manipulative and verbal capacity, attention, visual motor ability and disruptive behaviour, variables that have barely been studied in this kind of investigations. The sample comprised 760 schoolchildren from the province of Jaén (southern Spain). Our results show that children with low levels of iodine intake and with urinary iodine concentration lower than 100 microg/litre had a lower IQ and displayed more disruptive behaviour than children with high levels of the criteria. The other variables were not associated with iodine deficiency.
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Les literatures francòfones, relegades durant molts anys a una quasi total indiferència per part de la literatura francesa, han pres en els últims quinze anys una importància considerable. L'esforç per part de molts professors d'incloure aquestes literatures en els programes d'ensenyament està donant els seus fruits. L'interès suscitat per l'estudi de la literatura quebequesa i l'apogeu que està prenent a Catalunya –a més de les bones relacions Catalunya-Quebec– van ser el motor d’una recerca sobre la presència, la traducció i la recepció de la literatura de Quebec a Catalunya. Per tal de conèixer l’estat de la qüestió, es va procedir, en un primer temps, a un seguiment de tot el que s’havia publicat a Catalunya referent a la literatura del Quebec. Igualment, es va sondejar els treballs sobre aquesta matèria que no havien estat objecte de publicació i es va recopilar la diversa informació sobre les manifestacions culturals relacionades amb aquesta matèria. En un segon temps, es va procedir a l’estudi dels materials obtinguts i a la seva avaluació. Malgrat la presència recent de la literatura del Quebec a Catalunya i la manca de planificació institucional per dur a terme una traducció sistemàtica que permeti mostrar l’estat actual d’aquesta literatura, es troba, cada vegada més, una voluntat manifesta de donar a conèixer aquesta cultura provinent de Quebec ja sigui per afinitats o voluntats individuals o per respondre a les tendències de mercat.