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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

The role of self-efficacy in the initiation and maintenance of physical activity

Tang, Mei Yee January 2017 (has links)
Background: Self-efficacy is an important determinant of physical activity. Yet it remains unclear which behaviour change techniques (BCTs) are most effective at changing self-efficacy for physical activity. This PhD thesis aimed to explore issues surrounding which individual BCTs and clusters of BCTs that are most effective in initiating and maintaining changes in self-efficacy and physical activity behaviour across different adult populations through a systematic review with meta-analysis. This thesis consists of three linked papers which examined: 1) the individual and clusters of BCTs that are most effective in initiating and maintaining changes in self-efficacy and physical activity behaviour across all adult populations, 2) the individual BCTs which are effective in initiating self-efficacy and physical activity in two clinical samples (hypertension or heart disease, and pain or arthritis), and 3) the extent of theory use in interventions and examination of BCT use across theories. Methods: One hundred and eighty randomised trials which reported changes in self-efficacy were included into the review. Intervention content was reliably coded using the BCT Taxonomy v1 by two independent coders. From the 180 randomised trials, 204 comparisons were identified for the meta-analyses and moderator analyses. Meta-regressions examined whether the presence and absence of individual BCTs and intervention characteristics were associated with effect size changes for self-efficacy and physical activity. Chi-square analyses were conducted in Journal Article Three to examine for differences in BCT use across theories. Results: In Journal Article One, lack of meaningful clustering of BCTs was found. Interventions had small but significant effects on self-efficacy for the initiation of physical activity (d=0.26; 95%CI: [0.21, 0.31]) and physical activity (d= 0.21; 95%CI: [0.17, 0.26]) across all adult populations. Small effects were also found for the maintenance of physical activity self-efficacy behaviour, and these were non-statistically significant. In Journal Article Two, the interventions had small to medium sized significant effects on the initiation of physical activity self-efficacy and behaviour in hypertension or heart disease, and pain or arthritis samples. Few BCTs were found to moderate intervention effects on self-efficacy or physical activity in either clinical sample. In Journal Article Three, theory was not used extensively in interventions. Differences in the use of BCTs were found across theories, some of which mapped onto the constructs of the adopted theoretical frameworks. Conclusions: It seems that there are no specific sets of BCTs that are effective for changing self-efficacy and physical activity across all adult populations. In addition to BCTs, there needs to be further research into how communication styles and delivery characteristics can influence intervention effectiveness. It is also important to understand how BCTs and theory can be used optimally together, as there appears to be discrepancy between what theories proposes to be effective and what empirical evidence generated by this review suggests may be effective.
212

We just estimated twenty million fiscal multipliers

Capek, Jan, Crespo Cuaresma, Jesus 08 1900 (has links) (PDF)
We analyse the role played by data and specification choices as determinants of the size of the fiscal multipliers obtained using structural vector autoregressive models. The results, based on over twenty million fiscal multiplier estimated for European countries, indicate that many seemingly harmless modelling choices have a significant effect on the size and precision of fiscal multiplier estimates. In addition to the structural shock identification strategy, these modelling choices include the definition of spending and taxes, the national accounts system employed, the use of particular interest rates or inflation measures, or whether data are smoothed prior to estimation. / Series: Department of Economics Working Paper Series
213

Eficácia do uso de stents na dacriocistorrinostomia endoscópica metanálise /

Orsolini, Maria Julia de Barros January 2018 (has links)
Orientador: Silvana Artioli Schellini / Abstract: Objective: To determine if stents increase the success rate of endoscopic dacryocystorhinostomy (DCR-EN) Method: Systematic review of randomized clinical trials of DCR-EN, comparing surgeries performed with and without stents in children older than 10 years of age and adult patients, with primary lacrimo-nasal duct (LND) obstruction. The outcomes were LND patency and adverse events (complications). We searched the databases of Web of Science, Scopus, Embase, Cochrane, PubMed, Lilacs until May 2018. The RevMan 5.3 software provided by the Cochrane Collaboration was used for meta-analysis. Results: Ten studies involving 887 surgeries were included. Five studies were conducted in India, and each of the others were conducted in Canada, Turkey, Saudi Arabia, China and Finland. Lacrimo-nasal duct patency meta-analysis showed stents did not interfere in the chance of success in relation to non-use of the stents to obtain lacrimal viability (OR 1.62, 95% CI 1.00 to 2.64, I2 = 0%). It was not possible to perform a meta-analysis regarding the adverse effects and a descriptive analysis was made of the general complications and complications due to the stents. Conclusion: The use or no of stents in DCR-EN probably does not make any difference in the NLD patency. Further studies may better define whether there is a trend toward a better success rate with the use of stent. Key words: dacryocystorhinotomy, endoscopic, stent, success, meta-analysis / Resumo: Objetivo: Definir se o uso de stents aumenta a taxa de sucesso da dacriocistorrinostomia endoscópica (DCR-EN). Método: Revisão sistemática de ensaios clínicos randomizados referentes a DCR-EN, comparando as cirurgias realizadas com e sem uso de stents em crianças acima dos 10 anos de idade e adultos, com obstrução adquirida do ducto lacrimo-nasal (DLN). Os desfechos avaliados foram a patência do DLN e os eventos adversos (complicações). Foram pesquisadas as bases de dados: Web of Science, Scopus, Embase, Cochrane, PubMed, Lilacs até maio de 2018. Utilizou-se para metanálise o software RevMan 5.3 fornecido pela Colaboração Cochrane. Resultados: Dez estudos envolvendo 887 cirurgias foram incluidos. Cinco estudos foram realizados na India, um em cada um dos países a seguir: Canada, Turquia, Arabia Saudita, China e Finlândia. A metanálise da patência do DLN mostrou que os stents não interferiram na chance de sucesso em relação ao não uso dos stents para a obtenção de permeabilidade da via lacrimal (OR 1,62, IC 95% 1.00 a 2.64; I2 = 0%). Quanto aos efeitos adversos não foi possível realizar metanálise, tendo sido feita análise descritiva das complicações gerais e complicações dos stents. Conclusão: O uso ou não de stents na DCR-EN provavelmente faz pouca ou nenhuma diferença na patência do DLN. Novos estudos poderão melhor definir se há tendência de melhor taxa de sucesso com o uso de stents. / Mestre
214

Eficácia e segurança dos antiangiogênicos no tratamento da retinopatia da prematuridade revisão sistemática e metanálise /

Ogata, Matheus Senna Pereira January 2018 (has links)
Orientador: Eliane Chaves Jorge / Abstract: Background: The standard treatment of retinopathy of prematurity (ROP) is the ablation of the avascular retina with laser or cryotherapy. However, this therapy may leave permanent structural and visual sequelae and may not be effective in cases of posterior and aggressive ROP. Vascular endothelial growth factor (VEGF) is involved in the pathogenesis of ROP, and antiangiogenic therapy is an option in cases of failure of standard treatment. The potential adverse effects of the use of antiangiogenic drugs in preterm neonates and the lack of concrete evidence on the efficacy of these drugs justify a systematic review of the literature. Objective: To evaluate the efficacy and safety of antiangiogenic therapy, when compared with laser photocoagulation, cryotherapy or combination therapy, in the treatment of ROP. Method: A systematic review of the literature was conducted using the Cochrane collaboration methodology and electronic search platforms to identify studies using antiangiogenic drugs in the treatment of ROP. The quality of the evidence was evaluated by the GRADE system (Grading of Recommendations Assessment, Development, and Evaluation). Results: Twelve studies were included in this review (six randomized controlled trials - RCTs and six non-randomized observational studies), including 677 preterm infants. Through the meta-analyzes, there was a statistical difference benefiting anti-VEGF therapy in the occurrence of progression to retinal detachment (RR 0.14 [95% CI 0.05, ... (Complete abstract click electronic access below) / Resumo: Introdução: O tratamento padrão da retinopatia da prematuridade (ROP) é a ablação da retina avascular com laser ou crioterapia. No entanto, esta terapia pode deixar sequelas estruturais e visuais permanentes e não ser efetiva em casos de ROP posterior e agressiva. O fator de crescimento do endotélio vascular (VEGF) está envolvido na patogênese da ROP e a terapia antiangiogênica é opção nos casos de falha do tratamento padrão. Os potenciais efeitos adversos com o uso de antiangiogênicos em neonatos prematuros e a falta de evidências concretas sobre a eficácia destas drogas justifica uma revisão sistemática da literatura. Objetivo: Avaliar a eficácia e a segurança da terapia antiangiogênica, quando comparada com fotocoagulação a laser, crioterapia ou terapia combinada, no tratamento da ROP. Método: Uma revisão sistemática da literatura foi realizada, utilizando a metodologia da colaboração Cochrane e plataformas eletrônicas de busca para identificar estudos utilizando drogas antiangiogênicas no tratamento da ROP. A qualidade da evidência foi avaliada pelo sistema GRADE (Grading of Recommendations Assessment, Development and Evaluation). Resultados: Doze estudos foram incluídos nesta revisão (seis ensaios clínicos randomizados e seis estudos observacionais não randomizados), incluindo 677 recém-nascidos pré-termo (1288 olhos). Pelas metanálises, houve diferença estatística beneficiando a terapia anti-VEGF na ocorrência de progressão para descolamento de retina (RR 0.14 [IC 95% 0... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
215

The Prevalence of Religious Service Attendance in America: A Review and Meta-Analysis

Briggs, Chad S. 01 August 2017 (has links)
The Gallup Poll and General Social Survey have asked Americans about their religious service attendance since 1939 and 1972, respectively. With remarkable consistency, these two surveys have estimated that just over 40% of the American population regularly attends religious services. Yet, recent research has called this “gold standard” into question, citing three sources of bias in these estimates: (a) ambiguous item wording, (b) an ambiguously specified time frame; and (c) data collection methods that lend themselves to socially desirable responding. Several lines of research have developed to eliminate or minimize these sources of bias, but these efforts have yielded a wide variety of results, with some estimates being half as much as the gold standard! Methodological and psychometric differences are not the only source of variation, however. The characteristics of those sampled into studies also introduces variability. Given that attendance estimates are likely influenced by variations in both methodology and sampling, this study uses meta-analytic techniques to estimate the extent of their influence and to estimate the attendance rate after controlling for their influence. The findings indicate that efforts to reduce socially desirable responding have had the greatest impact on the attendance rate, followed by efforts to overcome the ambiguously specified time-frame. In addition, attendance rates are positively related to the proportion of African Americans, Whites and married respondents sampled, as well as mean years of education. Attendance rates are also negatively related to the proportion of 18 to 30 year-old respondents sampled. After controlling for these methodological and socio-demographic study characteristics, the prevalence of weekly attendance in America was variously estimated as 41.4% for the gold standard items, 43.1% for items measuring attendance in the past week, 27.8% when asking respondents what they did yesterday (i.e., on Sunday via the time-use methodology) and 22.7% when attendance was counted manually.
216

Associação da síndrome metabólica e periodontite : revisão sistemática e metanálise

Daudt, Luciana Dondonis January 2013 (has links)
OBJETIVO Avaliar as evidências quanto à associação entre síndrome metabólica e periodontite através de uma revisão sistemática da literatura e metanálise de estudos observacionais. MATERIAIS E MÉTODOS Os estudos foram acessados através de busca nas bases eletrônicas Medline, EMBASE e Biblioteca Cochrane e de busca manual para identificar estudos, observacionais, originais, realizados com população adulta, que avaliaram a associação entre síndrome metabólica e doença periodontal. Os estudos deveriam mencionar critério de diagnóstico para síndrome metabólica e pelo menos uma medida clínica para o diagnóstico de periodontite e apresentar as medidas de efeito através de razão de chance (OR), risco relativo (RR) ou taxa de prevalência (PR). Os dados foram extraídos por dois investigadores, de maneira independente. A metanálise dos estudos incluídos foi realizada utilizando-se modelos randômicos. RESULTADOS A revisão sistemática incluiu 17 estudos observacionais, que preencheram os critérios de inclusão. Na metanálise foram incluídos 11 estudos, totalizando dados de 38.189 pacientes. Encontrou-se associação entre síndrome metabólica e periodontite com um OR de 1,78 (IC 95% 1,38- 2,30), e heterogeneidade de i2=93%. Para investigar a alta heterogeneidade foram (1) rodadas análises sequenciais, excluindo-se um estudo por vez, (2) metarregressão avaliando-se isoladamente idade, tabagismo, critério de diagnóstico para síndrome metabólica e exame periodontal completo versus parcial, (3) análise de subgrupos analisando-se em separado estudos em população asiática e não asiática e análise de sensibilidade. A heterogeneidade foi reduzida de forma significativa quando subdividiu-se os estudos com origem em população asiática (OR 2,06, IC 95% 1,60– 2,85, i2= 83,1%) e em população não asiática (OR 1,12 IC 95% 1,04- 1,68, i2=65,3%). CONCLUSÃO Os achados deste estudo reportam uma associação significativa entre síndrome metabólica e doença periodontal. A falta de um número suficiente de estudos longitudinais impede que se estabeleça a direção desta associação. Devido a alta heterogeneidade encontrada, estudos de intervenção bem controlados são necessários para que se conheça a magnitude dessa associação. / PURPOSE To investigate the association of metabolic syndrome and periodontitis by means of a systematic review and a meta-analysis of observational studies. RESEARCH DESIGN AND METHODS The electronic databases Medline, EMBASE and The Cochrane Library were searched for observational studies that evaluated the association of Metabolic Syndrome and Periodontitis. Hand search was also done. Data extraction was performed by two reviewers independently. Pooled effect estimates were obtained by using random-effects meta-analysis. RESULTS Systematic review included 17 studies that fulfilled the inclusion criteria. Meta-analysis was done with 11 studies, providing data of 38.189 patients. The results showed that there is an association estimated in an OR of 1,78 (95%IC 1,38- 2,30) between metabolic syndrome and periodontitis. A high heterogeneity was present (i2=93%). To investigate heterogeneity (1) the meta-analysis was re-ran excluding studies one at a time, (2) univariate metaregression was performed analyzing smoke status, metabolic syndrome criteria and parcial versus complete periodontal record, (3) subgroup analysis splitting studies in those performed with Asiatic populations and with non-Asiatic populations and sensitivity analysis. The heterogeneity was reduced significantly when subgroup analysis was done, for Asiatic population an OR of 2,06 (95% IC 1,60-2,85) and i2= 83,1% and for non-Asiatic population an OR of 1,12 (95% IC 1,04- 1,68) and i2=65,3% were found. CONCLUSION This study showed a significant association between metabolic syndrome and periodontitis. The lack of longitudinal studies in this area prevent from setting the direction of this association. Due to the high heterogeneity found, interventional and well controlled studies are encouraged to elucidate the magnitude of this association.
217

Fatores da qualidade dos serviços prestados via internet e seus consequentes : uma revisão metanalítica

Lionello, Rafael Laitano January 2014 (has links)
Apesar de a qualidade ser considerada um dos principais determinantes da sobrevivência e prosperidade de prestadores de serviços via internet (eg, ZEITHAML; PARASURAMAM; MALHOTRA, 2000, 2002), existem muitas divergênciasna literatura a respeito da conceptualização, composição e consequências desse construto. A fim de ajudar no preenchimento dessa lacuna, este trabalho integrou os resultados quantitativos de 87 amostras independentes, reportados em 74 estudos (=35935), em um modelo metanalítico dos fatores da qualidade dos serviços prestados via internet (QSEI). Utilizando Rust e Oliver (1994) como referência teórica, os 10 fatores encontrados na literatura com frequência suficiente para análise (≥4) foram agrupados em 3 dimensões (qualidade do ambiente, do processo e do resultado) e associados à qualidade geral percebida, satisfação do cliente e intenção comportamental.Das 30 relações propostas, 25 alcançaram o ponto de corte estipulado (≥4) e puderam ser analisadas por meio da metanálise, quando se constatou que as relações eram significantes ao nível de 5%, bem como eram robustas no que diz respeito ao fail safe N. Com relação à magnitude dos efeitos observados, encontrou-se que o benefício funcional possui o maior efeito sobre a satisfação do cliente e a intenção comportamental, enquanto que a qualidade da informação possui o maior efeito sobre a qualidade geral percebida. O efeito do benefício funcional é maior do que o do benefício emocional tanto na satisfação do cliente quanto na intenção comportamental, sugerindo que as avaliações do cliente são mais cognitivas do que emocionais em contextos eletrônicos. O efeito do benefício funcional é maior do que o do benefício emocional tanto na satisfação do cliente quanto na intenção comportamental, sugerindo que as avaliações do cliente são mais cognitivas do que emocionais em contextos eletrônicos. Além disso, o benefício emocional, o benefício funcional e a confiabilidade estão entre os quatro fatores com maior efeito sobre a intenção comportamental, sugerindo que as intenções de comportamento do consumidor online são mais influenciadas pelos fatores associados ao final da experiência (dimensão qualidade do resultado). / Although quality has been recognizedas a major determinant of long-term performance and success for service providers on the internet (eg, ZEITHAML; PARASURAMAM; MALHOTRA, 2000, 2002), there are many divergences in the literature regarding the conceptualization, dimensionality and consequences of this construct. In order to help to fill this gap, it was integrated the quantitative results of 87 independent samples reported in 74 studies (N = 35935) in a meta-analytic model of service quality delivered through the Internet. Using Rust and Oliver (1994) as theoretical framework, the 10 factors found in the literature were grouped into 3 dimensions (environmental, process, and outcome quality) and associated to perceived quality, customer satisfaction, and behavioral intention. Thirty relationships were proposed, but only 25 of them reached the cutoff point (≥4)and were analyzed through the meta-analysis. These 25 relationships are significant at the 5% level and robust with regard to the fail safe N.The results indicate that the information quality is the most influential factor on the overall perceived quality, while the functional benefit is the most influential factor both on the customer satisfaction and behavioral intention. The functional benefit effect both on the customer satisfaction and behavioral intention is greater than that of emotional benefit, suggesting that the customer ratings are more cognitive than emotional in electronic contexts. Furthermore, the behavioral intention is most influenced by the outcome dimension factors (emotional benefit, functional benefit, and the reliability), demonstrating that the end of experience is very important for consumers at the internet.
218

The role of the sociocultural context in explaining variance in incidence of psychosis and higher rates of disorder in minorities

Jongsma, Hannah E. January 2018 (has links)
Over the past few decades, epidemiological evidence has accrued to establish variance in psychosis risk across both geographical locations and demographic characteristics such as the excess risk in migrants and their descendants. Yet, the causes of this variation in rates between places and ethnic groups are still unclear, and I aimed to address this in this thesis. I conducted a systematic review and meta-analyses to synthesise existing literature on psychosis incidence in the six countries included in the EUropean network of national schizophrenia networks studying Gene-Environment Interactions (EU-GEI) study: England, The Netherlands, Spain, France, Italy and Brazil. I subsequently analysed data from two parts of the EU-GEI study: a 17-centre service-based incidence study of psychosis, and a case-control arm utilising community volunteers. In the latter, I aimed to explain excess risk in ethnic and religious minorities using a theoretical sociocultural distance model I developed using literature from the social sciences. Here, I proposed that culturally distant minorities were particularly at risk of social exclusion, and this outsider experience led to increased psychosocial disempowerment (a lack of control over one’s life), which increased psychosis risk. I also explored if this model could explain any excess risk in those with increased genetic African ancestry in England. Incidence varied substantially between the studies included in the systematic review, although methodological differences could not be excluded as an explanation. The EU-GEI incidence study confirmed substantial variation by place, and demonstrated a higher incidence in ethnic minorities and for young men, as well as in areas characterised by a low percentage of owner-occupied housing. The sociocultural distance model could explain most of the excess psychosis risk in ethnic minorities, although some excess risk remained, particularly in the Black ethnic group. Social and cultural distance appeared to be more important predictors than psychosocial disempowerment, suggesting that chronic social injustices rather than acute stress play an important role. This model did not explain excess risk in religious minorities: those following any religion retained an excess risk. It could explain the excess risk in those with increased genetic African ancestry, although this was a small, exploratory sample and this will need replicating in larger studies. This thesis demonstrated, for the first time, that excess risk in ethnic minorities could be explained by the sociocultural distance model. Overall, the findings from this thesis confirm substantial variation in psychosis risk by person and place, and suggest that the social reality of the environment plays a crucial role in explaining this.
219

Eficácia e segurança dos antiangiogênicos no tratamento da retinopatia da prematuridade : revisão sistemática e metanálise / Efficacy and safety of anti-VEGF drugs in the treatment of retinopathy of prematurity. Systematic review and meta-analysis

Ogata, Matheus Senna Pereira 25 July 2018 (has links)
Submitted by MATHEUS SENNA PEREIRA OGATA (mspogata@gmail.com) on 2018-09-18T00:16:15Z No. of bitstreams: 1 Dissertação (REFERENCIAS CORRGIIDAS) - Matheus Senna Pereira Ogata.pdf: 3338159 bytes, checksum: a4719346512d617a2a7beeb12f2c4a85 (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-09-18T17:16:07Z (GMT) No. of bitstreams: 1 ogata_msp_me_bot.pdf: 3338159 bytes, checksum: a4719346512d617a2a7beeb12f2c4a85 (MD5) / Made available in DSpace on 2018-09-18T17:16:07Z (GMT). No. of bitstreams: 1 ogata_msp_me_bot.pdf: 3338159 bytes, checksum: a4719346512d617a2a7beeb12f2c4a85 (MD5) Previous issue date: 2018-07-25 / Introdução: O tratamento padrão da retinopatia da prematuridade (ROP) é a ablação da retina avascular com laser ou crioterapia. No entanto, esta terapia pode deixar sequelas estruturais e visuais permanentes e não ser efetiva em casos de ROP posterior e agressiva. O fator de crescimento do endotélio vascular (VEGF) está envolvido na patogênese da ROP e a terapia antiangiogênica é opção nos casos de falha do tratamento padrão. Os potenciais efeitos adversos com o uso de antiangiogênicos em neonatos prematuros e a falta de evidências concretas sobre a eficácia destas drogas justifica uma revisão sistemática da literatura. Objetivo: Avaliar a eficácia e a segurança da terapia antiangiogênica, quando comparada com fotocoagulação a laser, crioterapia ou terapia combinada, no tratamento da ROP. Método: Uma revisão sistemática da literatura foi realizada, utilizando a metodologia da colaboração Cochrane e plataformas eletrônicas de busca para identificar estudos utilizando drogas antiangiogênicas no tratamento da ROP. A qualidade da evidência foi avaliada pelo sistema GRADE (Grading of Recommendations Assessment, Development and Evaluation). Resultados: Doze estudos foram incluídos nesta revisão (seis ensaios clínicos randomizados e seis estudos observacionais não randomizados), incluindo 677 recém-nascidos pré-termo (1288 olhos). Pelas metanálises, houve diferença estatística beneficiando a terapia anti-VEGF na ocorrência de progressão para descolamento de retina (RR 0.14 [IC 95% 0.05, 0.38] p=0.0001, I2 = 0%) e ocorrência de miopia ( Diferença de média ponderada 0.25 [IC 95% 0.14, 0.37] p<0.0001, I2 = 76%). No desfecho recorrência de ROP houve diferença estatística beneficiando o laser (RR 1.88 [IC 95% 1.34, 2.63] p=0.0003, I2 = 82%). Não houve porém, diferença entre a terapia anti-VEGF e o laser quanto à ocorrência de complicações oculares (RR 0.84 [IC 95% 0.34, 2.08] p=0.71, I2 = 0%). Na análise de sub grupo, na comparação entre as zonas de acometimento da ROP, o anti-VEGF apresentou menor risco de recorrência exigindo retratamento que o laser, em prematuros com ROP em zona I (RR 0.23 [IC 95% 0.11, 0.49] p=0.0001, I2 = 61%). A qualidade da evidência pelo GRADE variou de muito baixa a baixa. Conclusões: Há evidências de que a terapia anti-VEGF, usada como monoterapia, quando comparada ao laser, reduz o risco de progressão para descolamento de retina, a ocorrência de miopia e o risco de recorrência de ROP em prematuros com doença na zona I. No entanto, ainda faltam evidências de qualidade que permitam atestar a segurança da terapia, especialmente quanto aos potenciais efeitos sistêmicos em prematuros. Palavras-chave: Retinopatia da Prematuridade, antiangiogênicos, metanálise. / Background: The standard treatment of retinopathy of prematurity (ROP) is the ablation of the avascular retina with laser or cryotherapy. However, this therapy may leave permanent structural and visual sequelae and may not be effective in cases of posterior and aggressive ROP. Vascular endothelial growth factor (VEGF) is involved in the pathogenesis of ROP, and antiangiogenic therapy is an option in cases of failure of standard treatment. The potential adverse effects of the use of antiangiogenic drugs in preterm neonates and the lack of concrete evidence on the efficacy of these drugs justify a systematic review of the literature. Objective: To evaluate the efficacy and safety of antiangiogenic therapy, when compared with laser photocoagulation, cryotherapy or combination therapy, in the treatment of ROP. Method: A systematic review of the literature was conducted using the Cochrane collaboration methodology and electronic search platforms to identify studies using antiangiogenic drugs in the treatment of ROP. The quality of the evidence was evaluated by the GRADE system (Grading of Recommendations Assessment, Development, and Evaluation). Results: Twelve studies were included in this review (six randomized controlled trials - RCTs and six non-randomized observational studies), including 677 preterm infants. Through the meta-analyzes, there was a statistical difference benefiting anti-VEGF therapy in the occurrence of progression to retinal detachment (RR 0.14 [95% CI 0.05, 0.38] p = 0.0001, I2 = 0%) and myopia occurrence (Weighted mean difference 0.25 [95% CI 0.14, 0.37] p <0.0001, I2 = 76%). At the end of ROP recurrence, there was a statistical difference benefiting the laser (RR 1.88 [95% CI 1.34, 2.63], p = 0.0003, I2 = 82%). There was, however, no difference between the anti-VEGF therapy and the laser in the occurrence of ocular complications (RR 0.84 [95% CI 0.34, 2.08] p = 0.71, I2 = 0%). In the subgroup analysis, in the comparison between the ROP involvement zones, the anti-VEGF presented a lower risk of recurrence requiring retreatment than the laser in premature infants with zone I ROP (RR 0.23 [95% CI 0.11, 0.49] p = 0.0001, I2 = 61%).The quality of the GRADE evidence varied from very low to low. Conclusions: There is evidence that anti-VEGF therapy, used as monotherapy, when compared to laser, reduces the risk of progression to retinal detachment, the occurrence of myopia, and the risk of recurrence of ROP in preterm infants with the disease in zone I.However, there is still a lack of quality evidence to attest to the safety of therapy, especially regarding potential systemic effects in preterm infants.
220

Meta-analysis of QTL for Fusarium head blight resistance in Chinese wheat landraces using genotyping by sequencing

Cai, Jin January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Guihua Bai / Guorong Zhang / Fusarium head blight (FHB) is a devastating fungal disease in wheat, reducing not only grain yield but also quality. The pathogen produces the mycotoxin deoxynivalenol (DON) that induces severe toxicological problems in human and animals. Using host resistance has been the most efficient way to control the disease. To identify quantitative trait loci (QTLs) for FHB resistance in Chinese landrace Haiyanzhong (HYZ), a recombinant inbred lines (RILs) population derived from a cross between HYZ and Wheaton was developed. The RILs were evaluated for percentage of symptomatic spikelets (PSS) in three greenhouse experiments, and genotyped using simple sequence repeats (SSRs) and single nucleotide polymorphism (SNPs) developed from genotyping-by-sequencing (GBS). Eight QTLs were identified for type II (PSS) resistance on chromosomes 5A, 6B, 7D, 2B (2), 3B, 4B, and 4D, with 5A as the major QTL. Ten SNPs closely linked to 5A, 6B, and 2B QTLs were successfully converted to Kompetitave allelic specific PCR (KASP) assays. To identify common QTLs across different populations, we constructed high-density GBS-SNP maps in an additional four RIL populations derived from the Chinese landraces, Wangshuibai (WSB), Baishanyuehuang (BSYH), Huangfangzhu (HFZ), and Huangchandou (HCD) and conducted meta-analysis of the QTLs for FHB resistance using a consensus map developed from the five populations. We identified six MQTLs on chromosomes 3BS (2), 3A, 3D, 2D, and 4D and 23 tightly linked GBS-SNPs to the MQTLs. These GBS-SNPs were successfully converted to KASPs. The KASPs linked to MQTLs can be used for pyramiding these QTL in breeding programs. To quickly reduce FHB damage in U.S. hard winter wheat (HWW), we transferred Fhb1, a major QTL with stable effects on FHB resistance, from Ning7840 into three adapted HWW cultivars Overland, Jagger, and Overley, by marker-assisted backcross (MAB), and assessed the effect of Fhb1 on FHB resistance in these different backgrounds. The results showed that Fhb1 can significantly lower FHB severity, Fusarium-damaged kernel (FDK), and DON accumulation in the all the three HWW backgrounds. Some of the selected lines showed high levels of FHB resistance, but agronomically similar traits as recurrent parents, can be used as resistant parents to improve HWW FHB resistance.

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