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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.
101

Avaliação do risco de metástases linfonodais no adenocarcinoma gástrico precoce que integra critérios expandidos de ressecção endoscópica em pacientes submetidos a gastrectomia / Risk assessment of lymph node metastases in early gastric adenocarcinoma fullfilling expanded endoscopic resection criteria in patients undergoing gastrectomy

Fernanda Cristina Simões Pessorrusso 18 June 2018 (has links)
INTRODUÇÃO: O adenocarcinoma gástrico precoce (AGP) atinge até a camada submucosa em profundidade, independentemente da presença de metástases linfonodais (MLF). Tumores mucosos, bem diferenciados, menores que 20 mm e sem ulceração são candidatos à ressecção endoscópica (RE) por mucosectomia com taxas de MLF praticamente nulas. Com o advento da técnica de dissecção endoscópica da submucosa (ESD) e após observar ausência de MLF em grande série de pacientes no Japão, foi sugerido que os critérios clássicos pudessem ser expandidos, evitando a gastrectomia em alguns pacientes. Em países ocidentais autores e sociedades têm visto com restrição a ESD para critérios expandidos devido à observação de MLF em alguns subgrupos. A análise crítica e validação dos critérios expandidos de RE para tratamento do AGP em coorte brasileira poderá indicar os pacientes com menor risco de metástases linfonodais nesta população, de modo a individualizar o tratamento com excelência e qualidade de vida. OBJETIVO: Avaliar a presença MLF em produtos de gastrectomia com linfadenectomia de pacientes elegíveis à ressecção endoscópica seguindo os critérios clássicos e expandidos. MÉTODO: Inclusão de pacientes com AGP submetidos a tratamento cirúrgico com dissecção linfonodal. Estadiamento linfonodal e avaliação de características clínicas, macroscópicas e histopatológicas segundo critérios de RE. RESULTADOS: Foram incluídos 389 espécimens cirúrgicos de gastrectomia, dentre os quais 135 cumpriam critérios para ressecção endoscópica. Nenhum dos 31 pacientes com critérios clássicos apresentou MLF (N = 31; 0% IC95% 0 - 13,4%). Dos 104 com critérios expandidos, 3 apresentaram MLF (N = 104; 2,9% IC95% 0,7 - 8,6%), todos pertencentes ao grupo de tumores indiferenciados sem ulceração e menores que 20 mm. Dos pacientes com indicação de tratamento cirúrgico houve 50 MLF positivos (N = 254; 19,7% IC95% 15,3 - 25,1%). CONCLUSÃO: Existe risco mínimo de metástases linfonodais quando adotados os critérios expandidos de RE. Este risco é praticamente nulo para os critérios clássicos e quando se exclui o tumor indiferenciado do critério expandido / INTRODUCTION: Early gastric cancer (EGC) is known to present low rate of lymph nodal metastasis (LNM). Gastrectomy with D2 lymphadenectomy is usually curative for EGC. Endoscopic submucosal dissection (ESD) is a well-accepted treatment modality for lesions that meet the classic criteria, a well-differentiated adenocarcinoma measuring less than 20 mm size and without ulceration. Expanded criteria for ESD have been recently proposed, based on null LNM rate from large gastrectomies series coming from Japan. The expanded criteria for ESD are as follows: intramucosal non-ulcerative well-differentiated tumor > 20 mm, intramucosal ulc mo <= 30 mm, intramucosal non-ulcera mo <= 20 mm, or superficially submucosal ( m1) mo <= 30 mm. There is some resistance to adoption of the expanded criteria, since patients with positive LNM have already been reported in western centers. OBJECTIVE: Evaluate LNM staging in patients who met the expanded endoscopic treatment criteria for ESD. METHOD: Evaluation of gastrectomy specimens including LNM staging of patients submitted to gastrectomy for EGC in a 39-year retrospective cohort. A senior pathologist reviewed the histology slides. RESULTS: A total of 389 surgical specimens were included, of whose 135 met criteria for endoscopic resection. None of the 31 patients with classic criteria had LNM. Of the 104 patients with expanded criteria, 3 had LNM (n = 104, 2.9% CI 95% 0.7 - 8.6%), all of them with undifferentiated tumors without ulceration and less than 20 mm. In the patients with surgical criteria there were 50 LNM positive (n = 254; 19.7% CI 95% 15.3 - 25.1%). CONCLUSION: There is minimal risk of LNM in EGC when expanded criteria for ESD are met. This risk is practically nil for the classic criteria and when the undifferentiated tumor is excluded of the expanded criteria. Refinement of the expanded criteria for the risk of LNM may be desirable. Meanwhile the decision to complement the endoscopic treatment with LNM dissection or D2 gastrectomy will have to take into consideration the individual risk of perioperative morbidity and mortality
102

Avaliação da hemostasia na Doença de Crohn subclínica: papel da atividade endoscópica / Hemostatic parameters in Crohn\'s Disease in clinical remission: role of endoscopic activity

Adriana Ribas Andrade 25 July 2018 (has links)
Introdução: Pacientes com Doença de Crohn (DC) apresentam alto risco de eventos tromboembólicos (TE), muitas vezes, associados a alta morbimortalidade. É conhecido o papel da inflamação na fisiopatologia da trombose na doença Inflamatória Intestinal (DII), entretanto, o significado da inflamação subclínica ainda se mantém obscuro na literatura. Este estudo avaliou o efeito da atividade endoscópica no perfil de coagulação dos pacientes com DC em remissão clínica. Métodos: entre os dias 22 de maio de 2015 e 26 de abril de 2017, foram triados 261 pacientes com DC em possível remissão clínica, sendo realizadas ao todo 229 colonoscopias. Das 229 colonoscopias realizadas, 164 pacientes estavam realmente em remissão clínica (confirmados com CDAI <= 150) e foram alocados em dois grupos: 75 no grupo de atividade endoscópica (AE) (SES-CD >= 7), 89 no grupo de remissão endoscópica (RE) (SES-CD <= 2). Cinquenta controles saudáveis pareados por sexo e idade foram eleitos. Medimos, nos 3 grupos, além da geração de trombina - pelo método Calibrated Automated Thrombogram (CAT), com e sem trombomodulina, - a atividade do fator tecidual (FT), fibrinogênio, D-dímero, Fator VIII, ADAMTS-13, Fator de von Willebrand - antígeno e cofator de ristocetina (cWF). Coletamos dados sobre a duração da doença, extensão, comportamento, localização, tratamento farmacológico, história prévia de cirurgias, calprotectina fecal, qualidade de vida (por meio do IBDQ), além dos fatores de risco para TE, como hospitalização recente, uso de corticoide atual, status do tabagismo, assim como marcadores de trombofilia hereditária ou adquirida. Seguimos os pacientes por 1 ano de observação, avaliando a variação no CDAI e IBDQ no período. Resultados: A maioria dos pacientes apresentou comprometimento ileocolônico (43%), com comportamento inflamatório (40%), seguido de estenosante (30%) e fistulizante (30%). 67% estavam em uso de imunossupressores e 52% em uso de biológicos. Os fatores de risco para TE e todos os outros marcadores de trombofilia, incluindo deficiência de proteína C e S, anticardiolipina, resistência à proteína C, antitrombina, mutações da protrombina e do Fator V, foram semelhantes em ambos os grupos, exceto pelo anticoagulante lúpico, maior no grupo de AE (8,1% vs. 1,3%, p=0,047). Como esperado, o grupo de AE apresentou níveis significativamente maiores de PCR, calprotectina fecal e plaquetas. Além disso, este grupo apresentou uma maior atividade do fator tecidual vs. o grupo de RE vs. controles (127 vs. 103 vs. 84, p = 0,001). Embora o grupo DC tivesse maiores níveis de FVW:Ag e FVW:RCo, FVW/ADAMTS-13, Fator VIII e trombomodulina vs. controles, não houve diferença estatística entre os grupos de AE e RE. Os níveis de geração de trombina foram semelhantes entre os 3 grupos, com ou sem trombomodulina. Conclusão: Esses dados evidenciam que existe uma disfunção endotelial inerente à DC, e, que, em pacientes com AE, essa disfunção pode ser ainda maior pela maior exposição do FT. Embora, a presença de inflamação e dano endotelial contribuam para esse estado procoagulante, em pacientes com doença subclínica, há um estado de compensação permanente, uma vez que a quantidade de trombina gerada foi a mesma entre os grupos. Este equilíbrio pode estar comprometido diante de outros fatores tromboembólicos, aumentando, assim, o risco de trombose / Background: Crohn\'s disease patients (CD) have a high risk of thromboembolic events (TE), often associated with high morbidity and mortality. Involvement of inflammation in TE is well known, but significance of the sub-clinical inflammation in this process is not the rule. Thus, the aim of this study is to evaluate the effect of the endoscopic activity in the coagulation profile in CD in clinical remission. Methods: Between May/2015 and April/2017, 261 CD patients in supposed clinical remission, were screened, and 229 had a colonoscopy done, resulting in the inclusion of 164 CD patients in clinical remission confirmed by a CDAI <= 150. They were allocated in two groups: 75 in the endoscopic activity (EA) group (SES-CD >= 7), and 89 in the endoscopic remission (ER) group (SES-CD <= 2). 50 healthy controls matched for sex and age were chosen. We measured in the 3 groups, in addition to the generation of thrombin - through the Calibrated Automated Thrombogram (CAT), with and without thrombomodulin, - the activity of tissue factor (TF), fibrinogen, D-dimer, Factor VIII, ADAMTS-13 and von Willebrand Factor - antigen (VWF) and ristocetin cofactor (VWF:RCo). We collected data regarding the duration of the disease, extension, behavior, location, pharmacological treatment, previous history of surgeries, fecal calprotectin, quality of life (through IBDQ), as well as risk factors for TE such as recent hospitalization, current corticoid use, smoking status, as well as markers of hereditary or acquired thrombophilia. We followed the patients for 1 year of observation, evaluating the variation in CDAI and IBDQ. Results: Most of the patients had ileocolonic involvement (43%), with inflammatory behavior (40%), followed by stenosing (30%) and fistulizing (30%). 67% were in use of immunosuppressors and 52% in use of biological drugs. Risk factors for TE besides other markers of thrombophilia, including protein C and S deficiency, anticardiolipin, protein C resistance, antithrombin, prothrombin and Factor V mutations, were similar in both groups except for the lupus anticoagulant, higher in the EA group (8.1% vs. 1.3%, p = 0.047). As expected, the EA group had significantly higher levels of CRP, fecal calprotectin and platelets. In addition, this group had a higher activity of TF vs. ER group vs. controls (127 vs. 103 vs. 84, p = 0.001). Although the DC group had had higher levels of VWF and VWF:RCo, VWF/ADAMTS-13, Factor VIII and thrombomodulin vs. controls, there was no statistical difference between the EA and ER groups. Thrombin generation levels were similar between the 3 groups, with or without thrombomodulin. Conclusion: These data show that there is an inherent endothelial dysfunction in CD, moreover in patients with EA, this dysfunction may be even greater, due to the exposure of TF. Although the presence of inflammation and endothelial damage contribute to this procoagulant condition, in patients with subclinical disease, there is a permanent compensatory state, since the amount of thrombin generated was the same between the groups. This balance may be compromised by other thromboembolic factors, thus increasing the risk of thrombosis
103

Fistulotomia papilar versus cateterização convencional para acesso biliar endoscópico: avaliação clínico-laboratorial / Papillary fistulotomy versus conventional cannulation for endoscopic bile access: clinical laboratory evaluation

Carlos Kiyoshi Furuya Júnior 07 December 2017 (has links)
Introdução: O sucesso da cateterização da via biliar é de importância para o diagnóstico e terapêutica nas afecções biliopancreáticas nos procedimentos de colangiopancreatografia retrógrada endoscópica (CPRE) e está associado a complicações graves e mortalidade. O objetivo do estudo foi comparar o sucesso, perfil laboratorial e as complicações da técnica de fistulotomia papilar direta com o acesso cateter e fio-guia. Métodos: No período de julho de 2010 a maio de 2017 foram selecionados e randomizados para CPRE em dois grupos: cateterização com cateter e fioguia (Grupo I) e a fistulotomia papilar (Grupo II). As curvas de amilase, lipase e proteína C reativa (T0, 12 e 24 horas) e as complicações (pancreatite, sangramento e perfuração) foram avaliadas após CPRE. Resultados: Foram incluídos 102 pacientes (66 do sexo feminino e 36 do masculino, com idade média de 59,11±18,7 anos) e divididos em 51 pacientes para Grupo I e 51 no Grupo II. Os sucessos das cateterizações dos Grupos I e II foram de 76,47% e 100%, respectivamente (p=0,0002). Doze pacientes (23,53%) do Grupo I foram considerados pacientes de cateterização difícil e submetidos à fistulotomia papilar com sucesso no acesso biliar. Foram observadas 13,7% (2 perfurações e 5 pancreatites leves) e 2 % (1 paciente com perfuração e pancreatite) complicações nos Grupos I e II, respectivamente (p=0,062). Conclusão: A fistulotomia papilar demonstrou maior eficácia na cateterização da via biliar e com menor índice de amilasemia e lipasemia em comparação a cateterização com papilótomo e fio guia. As complicações foram semelhantes entre as duas técnicas / Background: The success of biliary tract cannulation is important for the diagnosis and treatment of biliopancreatic diseases in endoscopic retrograde cholangiopancreatography (ERCP) procedures. ERCP is associated with severe complications and mortality. The aim of the study was to compare the success, laboratory profile and complications of the direct papillary fistulotomy technique with standard catheter and guidewire access. Methods: In the period from July 2010 to May 2017, two groups were selected and randomized for ERCP: cannulation with catheter and guidewire (Group I) and papillary fistulotomy (Group II). The curves of amylase, lipase and C-reactive protein (T0, 12 and 24 hours) and complications (pancreatitis, bleeding and perforation) were evaluated after ERCP. Results: A total of 102 patients (66 females and 36 males, mean age 59.11 ± 18.7 years) were divided into 51 patients for Group I and 51 for Group II. The success of cannulation was 76.47% and 100%, in Groups I and II, respectively (p = 0.0002). Twelve patients (23.53%) of Group I were considered to have difficult cannulation and were submitted to fistulotomy with successful biliary access. There were 13.73% (2 perforations and 5 mild pancreatitis) and 2% (1 patient with perforation and pancreatitis) complications in Groups I and II, respectively (p=0,062). Conclusion: Papillary fistulotomy demonstrated greater efficacy in the bile duct cannulation and presented lower serum amylase and lipase compared with standard catheter and guidewire cannulation. Complications were similar in the two techniques
104

Développement d'un dispositif médical innovant pour la prise en charge prénatale de la hernie de coupole diaphragmatique / Development of a new device for the prenatal care of congenital diaphragmatic hernia

Sananès, Nicolas 09 June 2017 (has links)
Nous avons développé un nouveau ballonnet pour l'occlusion trachéale fœtale par endoscopie (FETO) qui permet une levée de l'occlusion facile, par contrôle externe et non-invasive. Ce ballonnet "Smart-TO" permet d'éviter les problèmes liés au rétablissement des voies aériennes. La solution technique est basée sur une valve magnétique dont l'ouverture est contrôlée par le champ de fuite d'une IRM. L'ouverture de la valve provoque la vidange du ballonnet, qui est ensuite expulsé par les sécrétions pulmonaires. Les tests d'imperméabilité, d'occlusion et de fonctionnement sont prometteurs. Une toute première expérimentation sur le modèle du singe a montré la bonne fonctionnalité et fonctionnement du ballonnet "Smart-TO". D'autres tests in vitro ainsi que d'autres tests animaux sont prévus. Un brevet a été déposé en 2016. Une analyse de risques préliminaire, une exploration des chemins réglementaires et une étude de marché ont été initiés mais sont encore en cours. / We developed a new balloon for Fetal Endoscopic Tracheal Occlusion (FETO) which allows an easy, remotely controlled, and non-invasive reversal occlusion. This "Smart-TO" balloon to overcome issues related to the airway reestablishment. The technology is based on a magnetic valve whose opening is actuated by the fringe field of an MRI scanner. The opeing of the valve induces the deflation of the balloon, which is then washed out by the fluid coming out from the lungs. The impermeability, occlusion and operation tests are promising. A very first experimentation on the monkey model showed appropriate functionality and operation of the "Smart-TO" balloon. Further in vitro and animal tests are planned. A patent has been filed in 2016. Preliminary risk analysis, regulatory routes exploration, and market study have been started but are still ongoing.
105

Non-invasive quantitative evaluation of the exocrine pancreas in physiologic and pathologic conditions using functional magnetic resonance imaging

Bali, Maria Antonietta 30 May 2011 (has links)
The proposal of this work was to determine the contribution of functional MR imaging techniques, i.e. secretin-enhanced MRCP (S-MRCP) and dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging in the quantitative assessment of exocrine pancreatic function and perfusion.<p><p>The pancreas is both an exocrine and endocrine organ, though the exocrine tissue accounts for more than 90%. The exocrine pancreas is specialized in the synthesis and storage of digestive enzymes and in bicarbonate and water secretion in response respectively to various secretagogues (CCK, ach, GRP, VIP,…) and to secretin. <p>The arterial supply of the pancreas derives from branches of the celiac trunk and of the superior mesenteric artery. The microvascularity of the exocrine and the endocrine parts of the gland are anatomically and functionally separated, with differentially regulated blood perfusion. <p>Based on the knowledge of a close relationship between the activity of the gland and its blood supply, in normal conditions pancreatic perfusion responds to the functional state of the exocrine parenchyma: increased demands for exocrine secretions are associated with increased pancreatic blood flow. <p>The pancreatic gland can be involved at different degrees of severity in acute and chronic inflammatory processes due to various causes. In both processes microcirculatory changes occur and the pancreatic exocrine function can be impaired. Moreover, an exiguous microvascular component characterizes pancreatic ductal adenocarcinoma (PDA) related to a prominent stroma.<p><p><p>In the first section of this thesis, quantitative assessment of the pancreatic exocrine secretions was performed with S-MRCP in physiologic and non-physiologic conditions. The stimulating effect of secretin as well as the inhibitory effect of somatostatin on normal pancreas, both administered at different dose-regimens, were tested. The results of these investigations showed that quantitative S-MRCP is able to detect changes in pancreatic exocrine secretions correlated to the degree of stimulation or inhibition. <p>In pathologic settings, pancreatic exocrine secretions were assessed in chronic pancreatitis patients showing different degrees of severity, before and after endoscopic pancreatic duct drainage procedures (PDDP). In the group of patients presenting a reduced pancreatic exocrine reserve before treatment, quantitative S-MRCP showed a short-term improvement after PDDP. <p><p>In the second section, the feasibility and the reproducibility of DCE-MR imaging to quantify regional pancreatic perfusion was firstly investigated. DCE-MR imaging was performed in normal volunteers. Reference values for regional pancreatic perfusion were achieved with an intra-individual variability of 21%.<p>DCE-MR investigations were repeated during secretin stimulation and disclosed a significant increase of regional pancreatic perfusion in all individuals. <p>Secondly, DCE-MR imaging investigated benign and malignant focal pancreatic solid lesions and non tumoral tissue in patients undergoing pancreatic surgical resection. The purpose was to correlate DCE-MR quantitative parameters, (reflecting perfusion and/or permeability and the distribution volume fraction) with histologic features such as the degree of fibrosis and the microvascular density (MVD) in the corresponding tissues. A significant correlation was found between DCE-MR and histologic parameters: Ktrans was negatively correlated with the degree of fibrosis (high fibrosis was correlated with low perfusion), while the distribution volume fraction was positively correlated with the degree of fibrosis and with MVD (larger EES was correlated with high fibrosis and higher MVD). <p> / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
106

Development and Validation of an Administrative Data Algorithm to Identify Adults who have Endoscopic Sinus Surgery for Chronic Rhinosinusitis

Macdonald, Kristian I January 2016 (has links)
Objective: 1) Systematic review on the accuracy of Chronic Rhinosinusitis (CRS) identification in administrative databases; 2) Develop an administrative data algorithm to identify CRS patients who have endoscopic sinus surgery (ESS). Methods: A chart review was performed for all ESS surgical encounters at The Ottawa Hospital from 2011-12. Cases were defined as encounters in which ESS for performed for Otolaryngologist-diagnosed CRS. An algorithm to identify patients who underwent ESS for CRS was developed using diagnostic and procedural codes within health administrative data. This algorithm was internally validated. Results: Only three studies meeting inclusion criteria were identified in the systematic review and showed inaccurate CRS identification. The final algorithm using administrative and chart review data found that encounters having at least one CRS diagnostic code and one ESS procedural code had excellent accuracy for identifying ESS: sensitivity 96.0% sensitivity, specificity 100%, and positive predictive value 95.4%. Internal validation showed similar accuracy. Conclusion: Most published AD studies examining CRS do not consider the accuracy of case identification. We identified a simple algorithm based on administrative database codes accurately identified ESS-CRS encounters.
107

Využití fysiologických a patofysiologických tlakových poměrů v oblasti žlučových cest a pankreatu k diagnostice a terapii endoskopickou retrográdní cholangiopankreatografií u dětí / The use of physiological and pathophysiological pressure ratios in the area of the biliary ductal system and pancreas for diagnosis and treatment by endoscopic retrograde cholangiopancreatography

Keil, Radan January 2009 (has links)
:.In our work we wanted to confirm our clinical experience with therapy of biliary and pancreatic duct injuries from the endoscopic retrograde cholangiopancreatography (ERCP) which was done in 267. Children and infants with a variety of biliary tract disorders and traumatic injuries in the area of biliary and pancreatic duct.. Pressure of the bile plays the key role in the therapy of biliary tract injuries Therefore we have measured the pressure in biliary tract and duodenum before and after the sphincterotomy of Oddi sphincter. Thea aim of our study was to confirm the insertion of drainage into the biliary and pancreatic duct in children with injury in this area. Our results showed significant differences between biliary duct pressure and duodenal pressure in the patients before and after sphincterotomy of Oddi sphincter. This results on theoretical basis confirmed, that it is necessary in children after traumatic rupture of biliary duct to provide ERCP and insert a biliary drainage after sphincterotomy. With this procedure the biliary tract injury is healed ad integrum without surgical liver resection. To provide only papilosphincterotomy without biliary drainage is not sufficient. This new miniinvasive procedure plays a fundamental role in the therapy of blunt abdominal injuries in a children and infants...
108

Etude expérimentale de l'influence des mélanges gazeux sur la combustion sans flamme / An experimental study of the influence of the aerodynamic mixing on flameless combustion regime

Rottier, Christiane 02 March 2010 (has links)
Une étude expérimentale de l'influence des mélanges gazeux sur le régime de combustion sans flamme a été menée sur l'installation pilote du CORIA, en collaboration avec GDF SUEZ. La première partie de cette étude a été consacrée à la caractérisation détaillée de ce régime de combustion particulier au méthane pur avec et sans préchauffage de l'air comburant. Des mesures locales de température et concentrations d'espèces stables ont été réalisées à l'aide de thermocouples à fil fin et sonde de prélèvement. Une attention particulière a aussi été portée au développement et l'adaptation de techniques d'imagerie sur ce type de four : l'imagerie de chimiluminescence OH* pour la visualisation des zones de réaction et la PIV endoscopique afin d'obtenir des champs de vitesse de grandes dimensions malgré le fort confinement à haute température. L'analyse des résultats obtenus a permis de mettre en évidence le rôle principal de l'aérodynamique des jets turbulents de réactifs dans le four assurant l'obtention et la stabilisation de ce régime de combustion massivement diluée. Dans la seconde partie de cette étude, la faisabilité de l'utilisation d'hydrogène dans un four pilote fonctionnant en régime de combustion sans flamme a été démontrée. On retrouve toutes les caractéristiques intrinsèques à ce régime de combustion en termes de forte efficacité énergétique (lors du préchauffage de l'air) et très faibles émissions polluantes (CO et NOx) de ce régime massivement dilué, associé à la réduction des émissions de CO2 avec l'augmentation de la teneur en hydrogène dans le combustible. En fonctionnement à l'hydrogène pur et sans préchauffage de l?air, le four n?émet plus aucune espèce carbonée et quasiment pas de NOx ; on se rapproche d'un four à "zéro émission". / An experimental study of the influence of the aerodynamic mixing on flameless combustion regime has been carried out on the CORIA lab-scale facility with the collaboration of GDF SUEZ. A detailed characterisation of this innovating combustion mode, using pure methane as fuel, with and without air preheating is the first part of this study. Temperature and stable species concentrations measurements have been performed with fine wire thermocouple and sampling probe. Imaging techniques have been developed and adapted for in-furnace measurements: OH* chemiluminescence imaging for reaction zone visualization and endoscopic PIV in order to obtain large dimensions velocity fields in spite of the confinement. The results enable us to put in evidence the leading role of aerodynamic of the turbulent jets to ensure the stabilisation of this massive diluted combustion regime. The second part of this study concerns the use of hydrogen as fuel in the pilot furnace operating in flameless combustion regime. The main characteristics of this combustion regime have been found again: high efficiency and very low pollutant emissions (CO and NOx) associated to CO2 emissions reduction while increasing content of hydrogen in the fuel. With pure hydrogen and without air preheating, the furnace produces no carbon-species and nearly no NOx, condition close to a “zero-emission” furnace.
109

Achalázie jícnu - etiologie, patofyziologie a léčba. / Esophageal achalasia - etiology, pathophysiology and treatment.

Vacková, Zuzana January 2020 (has links)
Background: Achalasia is a primary esophageal motility disorder that can be classified into three types (I-III) based on high-resolution manometry (HRM). Exact pathogenesis is unknown, but immune-mediated processes and genetic predisposition play a role, which is supported by finding of a genetic risk variant (rs28688207 insertion) in HLA-DQB1 gene that is strongly associated with achalasia. Per-oral endoscopic myotomy (POEM) has become a standard treatment for achalasia, but the long-term efficacy, safety and impact on esophageal physiology are not fully understood. The aims of our studies were to perform the first genotype-phenotype analysis investigating the frequency of rs28688207 accross three HRM types of achalasia, to evaluate the efficacy and safety of POEM and to assess the post-POEM esophageal motility patterns. Patients and methods: These were three retrospective studies of prospectively collected data. Genotyping of the rs2868827 insertion was performed using real-time PCR in 347 patients from Czech Republic (n = 163), Germany (n = 114), Greece (n = 70). The efficacy and safety of POEM were evaluated in 133 patients treated in our center. The post-POEM esophageal motility was assessed using the Chicago Classification in 237 patients in whom HRM was performed prior to and after POEM....
110

Post-operative complications after endoscopic sinus surgery in patients with chronic rhinosinusitis

Sundström, Anna January 2022 (has links)
Background Chronic rhinosinusitis is an inflammatory condition of the nose and paranasal sinuses lasting more than 12 weeks. The common treatment is intranasal corticosteroids but if this treatment fails in relieving symptoms endoscopic sinus surgery (ESS) is considered - a common procedure in the Otolaryngology department in Örebro county. ESS can be assisted by image guided navigation (IGN).In a quality ensuring purpose, this study aimed to investigate the frequency and characteristics of post-operative complications after ESS and examining possible risk factors for complications. Methods Retrospective chart review study. The post-operative complication rate after ESS was calculated. Bivariate analysis was used to find potential factors associated with post-operative complications. The variables of significance were used in multivariate analysis. Result Out of 131 patients; 52 (39.7%) had any post-operative complication. 21 had major – and 35 had minor complications. Local infection was the most common complication. IGN was associated with an increased risk of complications, both minor (OR 2.4, 95% CI 1.0-5.6) and overall (OR 2.7, 95% CI 1.3-5.8). Extensive surgery was associated with an increased risk of complications, both major (OR 2.6, 95% CI 1.0-6.9) and overall (OR 2.2, 95% CI 1.0-4.6). Male sex was associated with increased risk of major complications (OR 2.3, 95% CI 1.2-15.5). Conclusion The complication rate is comparable to other studies with similar definition of complications. IGN assistance, extensive surgery and male sex were associated with an increased risk of complications. Further research should be performed before drawing conclusions determining why they increase the risk.

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