• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 304
  • 158
  • 21
  • 15
  • 14
  • 12
  • 10
  • 8
  • 5
  • 4
  • 4
  • 4
  • 3
  • 2
  • 2
  • Tagged with
  • 622
  • 223
  • 115
  • 77
  • 74
  • 69
  • 65
  • 63
  • 60
  • 59
  • 51
  • 50
  • 49
  • 45
  • 45
  • 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.
611

Développement d’un endomicroscope multiphotonique à deux couleurs pour l’imagerie du métabolisme énergétique cellulaire / Label- free in vivo in situ diagnostic imaging by cellular metabolism quantification with a flexible multiphoton endomicroscope

Leclerc, Pierre 28 September 2017 (has links)
La microscopie multiphotonique est une modalité d’imagerie de pointe offrant des opportunités d’avancées remarquables en biologie mais aussi dans le domaine médical. Afin d’en exploiter pleinement le formidable potentiel au cœur même de la pratique clinique, le développement de nombreuses sondes miniaturisées à fibre optique pour l’endomicroscopie multiphotonique (EMMP) a eu lieu depuis de nombreuses années et dans de nombreux laboratoires français et étrangers. Il s’est pour l'instant confronté à des limitations majeures comme l’impossibilité de recueillir les signaux d’auto-fluorescence des tissus qui sont intrinsèquement faibles comme ceux venant des co-enzymes métaboliques NADH et FAD. Cette limitation compromet l'utilité de l’EMMP en la restreignant à une imagerie morphologique requérant un marquage exogène des tissus. Ce manuscrit présente une architecture d’EMMP permettant de dépasser cette limitation, capable de proposer une imagerie fonctionnelle du métabolisme cellulaire en temps réel, in vivo, in situ, sans marquage. Le prototype d’EMMP proposé est une amélioration du précédent, où les Grisms en réflexions sont remplacés par des Grisms en transmission, permettant d’élargir la bande spectrale d’utilisation et la transmission du système. Ce prototype voit aussi l’adjonction d’un second laser excitateur afin d’accéder aux fluorescences du NADH et du FAD. Les résultats démontrent capable que nous sommes à même d’imager les fluorescences cellulaires intrinsèques au travers de 5 mètres de fibre optique avec une résolution subcellulaire. Parmi celles-ci nous sommes capables d’exciter et de collecter spécifiquement les fluorescences du NADH et du FAD. Enfin nous détectons assez de photons pour disposer d‘informations quantitatives et donc de proposer une image du rapport d’oxydo-réduction optique en endomicroscopie. / Nonlinear microscopy is a cutting edge imaging modality leading to remarkable step forward in biology but also in the clinical field. To use it at its full potential and at the very heart of clinical practice, there has been several development of fiber-based micro-endoscope. The application for those probes is now limited by few major restrictions, such as the impossibility to collect auto-fluorescence signal from tissues theses being inherently weak such as the fluorescence from NADH or FAD. This limitation reduces the usefulness of the micro-endoscope effectively restraining it to morphological imaging modality requiring staining of the tissue. Our aim is to go beyond this limitation, showing cellular metabolism monitoring, in real time, without any staining. The experimental setup is an upgrade of our precedent one where the reflection- based Grism stretcher is replace with a new generation transmission-based Grism stretcher. Another Laser was also added in order to tune the first laser at 860nm to allow FAD imaging and the second one to 760nm for NADH. The results prove that we assess and image the level of NADH and FAD at subcellular resolution through a five-meter-long fiber. Thus we demonstrate that we are capable of measuring the optical redox ratio in a micro-endoscopic configuration.
612

"Avaliação imunohistoquímica das células inflamatórias presentes na parede de artérias pulmonares periféricas de pacientes com doença vaso-oclusiva pulmonar secundária a defeitos cardíacos congênitos" / Immunohystochemical evaluation of inflammatory cells in the walls of peripheral pulmonary arteries from patients with pulmonary vasoclusive disease secondary to cardiac congenital defects

Rubens Fraga Alves Pinto 11 August 2004 (has links)
Para avaliar a hipótese da presença de inflamação em artérias pulmonares periféricas de pacientes com hipertensão pulmonar (HP) decorrente de cardiopatias congênitas, foram quantificadas células inflamatórias através de marcação imunohistoquímica em biópsias de 26 pacientes e comparadas com 11 controles sem cardiopatia. Detectou-se quantidades semelhantes de células inflamatórias nos dois grupos, mas com predomínio de linfócitos T no grupo controle e de macrófagos jovens no grupo HP. Esses achados podem estar relacionados com a redução do estímulo dependente de macrófagos para diferenciação e maturação de linfócitos T nos cardiopatas e/ou a deficiência imunológica primária nesses pacientes / To evaluate the hypothesis of increased inflammation in peripheral pulmonary arteries from patients with pulmonary hypertension secondary to congenital cardiac shunts, we quantified the inflammatory cells with the aid of immunohystochemistry in 26 biopsies (HP group), comparing them to 11 patients with no cardiac disease. Similar quantities of inflammatory cells were observed in the two groups, with a predominance of T-lymphocytes in the controls and of young macrophages in the HP group. These findings could be related to a reduction of macrophagic stimulus to the differentiation and maturation of T-lymphocytes and/or to a primary immunological deficiency in patients with congenital cardiac shunts
613

Masses kystiques latérales du cou : une analyse comparative des approches diagnostiques

Tabet, Paul 08 1900 (has links)
Les masses kystiques latérales du cou (MKLC) bénignes et malignes sont difficiles à différencier cliniquement. L’utilité des modalités d’imagerie et de prélèvement doit être clarifiée. Une revue rétrospective de cas entre 2010 et 2016. Les données d’imagerie ont été récoltées et plusieurs variables propres à la masse furent analysées. Les rapports de cytoponction à l’aiguille fine (CAAF), de la biopsie au trocart (BT) et des examens extemporanés (EE) ont été analysés. La sensibilité, la spécificité, la valeur prédictive positive (VPP) et la valeur prédictive négative (VPN) pour prédire la malignité ont été calculées pour toutes les variables comparées entre les masses kystiques bénignes et malignes. Aucune variable d’imagerie n’a pu différencier les masses kystiques bénignes de malignes. La sensibilité de la CAAF est plus basse que celle de la BT (59% vs 83%; p=0.036) et de l’EE (59% vs 93%; p=0.01). L’EE a une meilleure VPN que la CAAF (92% vs 40%; p<0.001) et que la BT (92% vs 50%; p=0.062). La VPP et la spécificité étaient similaires dans tous les groupes. Les cliniciens ne peuvent pas se fier uniquement à l’imagerie pour différencier les masses bénignes des masses malignes. Vu sa VPP adéquate (92%), la CAAF devrait être utilisée initialement pour tous les patients avec une MKLC. Si la CAAF s’avère négative, la BT devrait être utilisée vu sa meilleure sensibilité. Un examen extemporané devrait toujours suivre une BT négative vu la faible VPN de la BT. Un résultat positif à l’une des trois modalités de prélèvement indique la présence de malignité. / Benign and malignant lateral cystic neck masses (LCNM) are difficult to distinguish clinically. The usefulness of imaging and sampling modalities in clarifying the diagnosis remains unclear. Retrospective review of cases between 2010 and 2016. Imaging data was reviewed and the variables pertaining to the mass were assessed including the following: size, nodal level, fat stranding, extracapsular spread, calcifications, vascularity, necrosis and standardized uptake value. Sampling reports of fine-needle aspiration (FNA), core-needle biopsy (CNB) and frozen section (FS) were also assessed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for predicting malignancy were calculated for all variables and compared between benign and malignant cystic neck masses. Ultrasound was used in 47.2% and CT-Scan in 90.5% of patients. No variables on imaging could definitely differentiate benign from malignant LCNM. FNA had a lower sensitivity then CNB (59% vs 83%; p=0.036) and FS (59% vs 93%; p=0.01). FS had a better NPV when compared to FNA (92% vs 40%; p<0.001) and CNB (92% vs 50%; p=0.062). Specificities and PPV were similar among all groups. Clinicians cannot rely on imaging to differentiate benign from malignant LCNM. Given its adequate PPV (92%), FNA should be used initially on lateral cystic neck masses. Because of its high sensitivity, CNB should be considered if FNA is not diagnostic of malignancy. FS should always follow a CNB not indicative of malignancy, because of the low NPV. Any result diagnostic of malignancy on either FNA, CNB or FS strongly indicates presence of malignancy.
614

Příspěvek k radiodiagnostice a k léčbě vybraných patologických lézí femuru v dětském a dospělém věku / Contribution to radiodiagnostics and to treatment of chosen pathological lesions of femur in childhood and in adults

Horák, Martin January 2014 (has links)
7 Abstract (AJ) Introduction Radiology examination using specialized modern imaging methods, including CT and MRI, is essential in the diagnosis of congenital and acquired diseases of the musculoskeletal system. The first part of the dissertation deals with certain congenital defects of the short femur, known in the literature as proximal femoral focal deficiency (PFFD). This part summarizes our experience with the radiological findings in the preoperative and postoperative period, with the main attention to the vascular supply to the affected area. The second part of the presentation deals with some aspects of autologous chondrocyte transplantation fixed at two different carriers implanted into post-traumatic articular cartilage defects of the distal femur. Radiological findings are evaluated in the relation to the histopathological findings. Objectives The first part of the study after the distribution of patients with PFFD by current commonly used radiographic classification sets the objective in the extent of scans of the hip joints to specify diagnosis PFFD in each patient and to evaluate in detail changes in the area of disability, especially a course of blood vessels. The evaluation of the radiation burden of repeated X-ray measurements was done with respect to the age of the patients. Tissue samples...
615

Význam biopsie sentinelové uzliny v léčbě pacientek s časným stádiem karcinomu děložního hrdla / The role of sentinel lymph node biopsy in the management of patients with early-stage cervical cancer

Kocián, Roman January 2021 (has links)
The sentinel lymph node biopsy is part of recommended surgical staging guidelines in patients with early stages of cervical cancer. High success rates of bilateral detection of SLN are achieved in sites with adequate experience with this procedure. The sentinel lymph node biopsy without systematic pelvic lymph node dissection is currently considered inadequate procedure for stages IB to IIA of the disease. One of the benefits of sentinel lymph node detection is extensive histopathological examination using the ultrastaging protocol enabling detection of small metastases (i.e. micrometastases). At the moment, there is lack of evidence about oncological safety of sentinel lymph node biopsy which might replace systematic lymph node dissection in the future. Prognostic significance of micrometastases is also controversial due to the lack of data about their potential presence in non-sentinel lymph nodes in cases with negative sentinel lymph nodes. This dissertation deals with the concept of sentinel lymph node biopsy in the cervical cancer and focuses on several topics. We have shown that the presence of micrometastasis is associated with significant negative impact on patients' prognosis on the largest retrospective cohort of patients ever published. Only 67% of patients with micrometastasis have...
616

Ultrasound shear wave imaging for diagnosis of nonalcoholic fatty liver disease

Yazdani, Ladan 04 1900 (has links)
Pour le diagnostic et la stratification de la fibrose hépatique, la rigidité du foie est un biomarqueur quantitatif estimé par des méthodes d'élastographie. L'élastographie par ondes de cisaillement (« shear wave », SW) utilise des ultrasons médicaux non invasifs pour évaluer les propriétés mécaniques du foie sur la base des propriétés de propagation des ondes de cisaillement. La vitesse des ondes de cisaillement (« shear wave speed », SWS) et l'atténuation des ondes de cisaillement (« shear wave attenuation », SWA) peuvent fournir une estimation de la viscoélasticité des tissus. Les tissus biologiques sont intrinsèquement viscoélastiques et un modèle mathématique complexe est généralement nécessaire pour calculer la viscoélasticité en imagerie SW. Le calcul précis de l'atténuation est essentiel, en particulier pour une estimation précise du module de perte et de la viscosité. Des études récentes ont tenté d'augmenter la précision de l'estimation du SWA, mais elles présentent encore certaines limites. Comme premier objectif de cette thèse, une méthode de décalage de fréquence revisitée a été développée pour améliorer les estimations fournies par la méthode originale de décalage en fréquence [Bernard et al 2017]. Dans la nouvelle méthode, l'hypothèse d'un paramètre de forme décrivant les caractéristiques spectrales des ondes de cisaillement, et assumé initialement constant pour tous les emplacements latéraux, a été abandonnée permettant un meilleur ajustement de la fonction gamma du spectre d'amplitude. En second lieu, un algorithme de consensus d'échantillons aléatoires adaptatifs (« adaptive random sample consensus », A-RANSAC) a été mis en œuvre pour estimer la pente du paramètre de taux variable de la distribution gamma afin d’améliorer la précision de la méthode. Pour valider ces changements algorithmiques, la méthode proposée a été comparée à trois méthodes récentes permettant d’estimer également l’atténuation des ondes de cisaillements (méthodes de décalage en fréquence, de décalage en fréquence en deux points et une méthode ayant comme acronyme anglophone AMUSE) à l'aide de données de simulations ou fantômes numériques. Également, des fantômes de gels homogènes in vitro et des données in vivo acquises sur le foie de canards ont été traités. Comme deuxième objectif, cette thèse porte également sur le diagnostic précoce de la stéatose hépatique non alcoolique (NAFLD) qui est nécessaire pour prévenir sa progression et réduire la mortalité globale. À cet effet, la méthode de décalage en fréquence revisitée a été testée sur des foies humains in vivo. La performance diagnostique de la nouvelle méthode a été étudiée sur des foies humains sains et atteints de la maladie du foie gras non alcoolique. Pour minimiser les sources de variabilité, une méthode d'analyse automatisée faisant la moyenne des mesures prises sous plusieurs angles a été mise au point. Les résultats de cette méthode ont été comparés à la fraction de graisse à densité de protons obtenue de l'imagerie par résonance magnétique (« magnetic resonance imaging proton density fat fraction », MRI-PDFF) et à la biopsie du foie. En outre, l’imagerie SWA a été utilisée pour classer la stéatose et des seuils de décision ont été établis pour la dichotomisation des différents grades de stéatose. Finalement, le dernier objectif de la thèse consiste en une étude de reproductibilité de six paramètres basés sur la technologie SW (vitesse, atténuation, dispersion, module de Young, viscosité et module de cisaillement). Cette étude a été réalisée chez des volontaires sains et des patients atteints de NAFLD à partir de données acquises lors de deux visites distinctes. En conclusion, une méthode robuste de calcul du SWA du foie a été développée et validée pour fournir une méthode de diagnostic de la NAFLD. / For diagnosis and staging of liver fibrosis, liver stiffness is a quantitative biomarker estimated by elastography methods. Ultrasound shear wave (SW) elastography utilizes noninvasive medical ultrasound to assess the mechanical properties of the liver based on the monitoring of the SW propagation. SW speed (SWS) and SW attenuation (SWA) can provide an estimation of tissue viscoelasticity. Biological tissues are inherently viscoelastic in nature and a complex mathematical model is usually required to compute viscoelasticity in SW imaging. Accurate computation of attenuation is critical, especially for accurate loss modulus and viscosity estimation. Recent studies have made attempts to increase the precision of SWA estimation, but they still face some limitations. As a first objective of this thesis, a revisited frequency-shift method was developed to improve the estimates provided by the original implementation of the frequency-shift method [Bernard et al 2017]. In the new method, the assumption of a constant shape parameter of the gamma function describing the SW magnitude spectrum has been dropped for all lateral locations, allowing a better gamma fitting. Secondly, an adaptive random sample consensus algorithm (A-RANSAC) was implemented to estimate the slope of the varying rate parameter of the gamma distribution to improve the accuracy of the method. For the validation of these algorithmic changes, the proposed method was compared with three recent methods proposed to estimate SWA (frequency-shift, two-point frequency-shift and AMUSE methods) using simulation data or numerical phantoms. In addition, in vitro homogenous gel phantoms and in vivo animal (duck) liver data were processed. As a second objective, this thesis also aimed at improving the early diagnosis of nonalcoholic fatty liver disease (NAFLD), which is necessary to prevent its progression and decrease the overall mortality. For this purpose, the revisited frequency-shift method was tested on in vivo human livers. The new method's diagnosis performance was investigated with healthy and NAFLD human livers. To minimize sources of variability, an automated analysis method averaging measurements from several angles has been developed. The results of this method were compared to the magnetic resonance imaging proton density fat fraction (MRI-PDFF) and to liver biopsy. SWA imaging was used for grading steatosis and cut-off decision thresholds were established for dichotomization of different steatosis grades. As a third objective, this thesis is proposing a reproducibility study of six SW-based parameters (speed, attenuation, dispersion, Young’s modulus, viscosity and shear modulus). The assessment was performed in healthy volunteers and NAFLD patients using data acquired at two separate visits. In conclusion, a robust method for computing the liver’s SWA was developed and validated to provide a diagnostic method for NAFLD.
617

"Contribuição ao estudo da influência da radiação ionizante pré-operatória sobre a marcação do linfonodo sentinela do reto com azul patente: estudo experimental em ratos" / Contribution to the study of the influence of preoperative ionizing radiation on the identification of the sentinel lymph node with patent blue : an experimental study in rats

Fernandes, Margareth da Rocha 06 February 2006 (has links)
A radiação ionizante prévia promove alterações actínicas em tecidos peritumorais,o que poderia influenciar a demarcação do linfonodo sentinela.O presente estudo desenvolveu modelo experimental para demarcação do linfonodo sentinela do reto do rato e para definição da dose de radiação (curva de calibração). O objetivo foi avaliar a influência da radiação ionizante pré-operatória sobre a marcação, com corante azul patente, do linfonodo sentinela do reto de ratos. A amostra foi constituída por 40 ratos machos Wistar e dividida em 2 grupos:Grupo 1 (controle não irradiado; n = 20) e Grupo 2 (irradiado com 1200cGy e demarcado 2 dias após; n = 20). Foi observado aumento linear do tempo de coloração do linfonodo no Grupo 2. Concluindo,a irradiação pré-operatória não influiu na demarcação do linfonodo sentinela do reto do rato / Previous ionizing radiation induces actinic alterations in peritumoral tissues and thus might influence the localization of the sentinel lymph node. The present study developed an experimental model for the localization of the sentinel lymph node of the rectum of the rat and for the definition of the dose of radiation (calibration curve). The objective was to evaluate the influence of preoperative ionizing radiation on the staining of a patent blue dye in the sentinel lymph node of the rectum in rats.The sample was composed of 40 male Wistar rats and was divided in two groups: Group 1 (non-irradiated control; n = 20 ) and Group 2(irradiated with 1200cGy and stained 2 days afterwards; n = 20). It was observed a linear increase in the time for the staining of the lymph in Group 2.In conclusion, preoperative irradiation did not influence the staining of the sentinel lymph node of the rectum in rats
618

Rastreamento da displasia anal em pacientes infectados pelo HIV: há concordância entre o estregaço anal e a biópsia guiada por anuscopia de alta resolução? / Screening anal dysplasia in HIV-infected patients : is there an agreement between anal pap smear and high resolution anoscopy guided biopsy?

Nahas, Caio Sergio Rizkallah 19 April 2012 (has links)
OBJETIVO: O objetivo deste estudo foi analisar a concordância entre o esfregaço anal e a biópsia guiada por anuscopia de alta resolução no diagnóstico da displasia anal em pacientes infectados pelo HIV. MÉTODO: Conduzimos uma análise transversal de pacientes infectados pelo HIV submetidos a rastreamento de displasia anal rotineiro. A concordância entre mensurações foi estimada por índice de kappa ponderado através de sistema de avaliação citológica e histológica de três categorias (normal, displasia de baixo grau, e displasia de alto grau). Estimativas de sensibilidade, especificidade e valores preditivos foram calculados através de sistema de avaliação citológica e histológica de duas categorias (ausência de displasia e displasia de qualquer grau). Estimativas foram calculadas também para a detecção de displasia de alto grau. RESULTADOS: No decorrer de um ano, 222 pacientes foram submetidos a 330 esfregaços anais seguidos de biópsias guiadas por anuscopia de alta resolução. Trezentos e onze (311) esfregaços com biópsias concomitantes foram satisfatórios. Considerando-se a histologia como padrão, a freqüência de displasia anal foi de 46%. O índice kappa ponderado para concordância entre o esfregaço anal e a biópsia foi de 0,20. Para detecção de displasia anal de qualquer grau, o esfregaço anal demonstrou sensibilidade de 61%, especificidade de 60%, valor preditivo positivo de 56% e valor preditivo negativo de 64%. Para displasia de alto grau, o esfregaço anal demonstrou sensibilidade de 16% e especificidade de 97%. CONCLUSÃO: Os resultados obtidos no presente estudo, em que comparamos os achados da citologia dos esfregaços com os achados histológicos das biópsias dirigidas pela anuscopia de alta resolução em pacientes infectados pelo HIV permitiram concluir que houve baixa concordância entre eles / Purpose: To analyze the agreement between anal Pap smear and high resolution anoscopy guided biopsy to diagnose anal dysplasia in HIV-infected patients. Methods: Cross sectional analysis of HIV-infected patients receiving anal dysplasia screening as part of routine care. Agreement between measures was estimated by weighted kappa-statistics, using 3-tiered cytologic and histologic grading system (normal, low grade dysplasia, and high grade dysplasia). Estimates of sensitivity, specificity, and predictive values were calculated using a 2-tiered cytologic and histologic grading system (without dysplasia, and with dysplasia of any grade). Estimates were also calculated for the detection of high grade dysplasia. Results: Two hundred and twenty-two patients underwent 330 anal Pap smears followed by high resolution anoscopy guided biopsies in one year period. There were 311 satisfactory Pap smears with concurrent biopsy. Considering histology the standard, the frequency of anal dysplasia was 46 percent (95 percent confidence interval: 40-51 percent). Kappa-agreement between anal Pap smear and biopsy was 0.20 (95 percent confidence interval: 0.10 0.29). Anal Pap smear showed sensitivity of 61 percent, specificity of 60 percent, positive predictive value of 56 percent, and negative predictive value of 64 percent for detection of anal dysplasia of any grade. For high grade dysplasia, anal Pap smear showed sensitivity of 16 percent, and specificity of 97 percent. Conclusion: The present study showed a low concordance between anal Pap smears and high resolution anoscopy-guided biopsy
619

Rastreamento da displasia anal em pacientes infectados pelo HIV: há concordância entre o estregaço anal e a biópsia guiada por anuscopia de alta resolução? / Screening anal dysplasia in HIV-infected patients : is there an agreement between anal pap smear and high resolution anoscopy guided biopsy?

Caio Sergio Rizkallah Nahas 19 April 2012 (has links)
OBJETIVO: O objetivo deste estudo foi analisar a concordância entre o esfregaço anal e a biópsia guiada por anuscopia de alta resolução no diagnóstico da displasia anal em pacientes infectados pelo HIV. MÉTODO: Conduzimos uma análise transversal de pacientes infectados pelo HIV submetidos a rastreamento de displasia anal rotineiro. A concordância entre mensurações foi estimada por índice de kappa ponderado através de sistema de avaliação citológica e histológica de três categorias (normal, displasia de baixo grau, e displasia de alto grau). Estimativas de sensibilidade, especificidade e valores preditivos foram calculados através de sistema de avaliação citológica e histológica de duas categorias (ausência de displasia e displasia de qualquer grau). Estimativas foram calculadas também para a detecção de displasia de alto grau. RESULTADOS: No decorrer de um ano, 222 pacientes foram submetidos a 330 esfregaços anais seguidos de biópsias guiadas por anuscopia de alta resolução. Trezentos e onze (311) esfregaços com biópsias concomitantes foram satisfatórios. Considerando-se a histologia como padrão, a freqüência de displasia anal foi de 46%. O índice kappa ponderado para concordância entre o esfregaço anal e a biópsia foi de 0,20. Para detecção de displasia anal de qualquer grau, o esfregaço anal demonstrou sensibilidade de 61%, especificidade de 60%, valor preditivo positivo de 56% e valor preditivo negativo de 64%. Para displasia de alto grau, o esfregaço anal demonstrou sensibilidade de 16% e especificidade de 97%. CONCLUSÃO: Os resultados obtidos no presente estudo, em que comparamos os achados da citologia dos esfregaços com os achados histológicos das biópsias dirigidas pela anuscopia de alta resolução em pacientes infectados pelo HIV permitiram concluir que houve baixa concordância entre eles / Purpose: To analyze the agreement between anal Pap smear and high resolution anoscopy guided biopsy to diagnose anal dysplasia in HIV-infected patients. Methods: Cross sectional analysis of HIV-infected patients receiving anal dysplasia screening as part of routine care. Agreement between measures was estimated by weighted kappa-statistics, using 3-tiered cytologic and histologic grading system (normal, low grade dysplasia, and high grade dysplasia). Estimates of sensitivity, specificity, and predictive values were calculated using a 2-tiered cytologic and histologic grading system (without dysplasia, and with dysplasia of any grade). Estimates were also calculated for the detection of high grade dysplasia. Results: Two hundred and twenty-two patients underwent 330 anal Pap smears followed by high resolution anoscopy guided biopsies in one year period. There were 311 satisfactory Pap smears with concurrent biopsy. Considering histology the standard, the frequency of anal dysplasia was 46 percent (95 percent confidence interval: 40-51 percent). Kappa-agreement between anal Pap smear and biopsy was 0.20 (95 percent confidence interval: 0.10 0.29). Anal Pap smear showed sensitivity of 61 percent, specificity of 60 percent, positive predictive value of 56 percent, and negative predictive value of 64 percent for detection of anal dysplasia of any grade. For high grade dysplasia, anal Pap smear showed sensitivity of 16 percent, and specificity of 97 percent. Conclusion: The present study showed a low concordance between anal Pap smears and high resolution anoscopy-guided biopsy
620

"Contribuição ao estudo da influência da radiação ionizante pré-operatória sobre a marcação do linfonodo sentinela do reto com azul patente: estudo experimental em ratos" / Contribution to the study of the influence of preoperative ionizing radiation on the identification of the sentinel lymph node with patent blue : an experimental study in rats

Margareth da Rocha Fernandes 06 February 2006 (has links)
A radiação ionizante prévia promove alterações actínicas em tecidos peritumorais,o que poderia influenciar a demarcação do linfonodo sentinela.O presente estudo desenvolveu modelo experimental para demarcação do linfonodo sentinela do reto do rato e para definição da dose de radiação (curva de calibração). O objetivo foi avaliar a influência da radiação ionizante pré-operatória sobre a marcação, com corante azul patente, do linfonodo sentinela do reto de ratos. A amostra foi constituída por 40 ratos machos Wistar e dividida em 2 grupos:Grupo 1 (controle não irradiado; n = 20) e Grupo 2 (irradiado com 1200cGy e demarcado 2 dias após; n = 20). Foi observado aumento linear do tempo de coloração do linfonodo no Grupo 2. Concluindo,a irradiação pré-operatória não influiu na demarcação do linfonodo sentinela do reto do rato / Previous ionizing radiation induces actinic alterations in peritumoral tissues and thus might influence the localization of the sentinel lymph node. The present study developed an experimental model for the localization of the sentinel lymph node of the rectum of the rat and for the definition of the dose of radiation (calibration curve). The objective was to evaluate the influence of preoperative ionizing radiation on the staining of a patent blue dye in the sentinel lymph node of the rectum in rats.The sample was composed of 40 male Wistar rats and was divided in two groups: Group 1 (non-irradiated control; n = 20 ) and Group 2(irradiated with 1200cGy and stained 2 days afterwards; n = 20). It was observed a linear increase in the time for the staining of the lymph in Group 2.In conclusion, preoperative irradiation did not influence the staining of the sentinel lymph node of the rectum in rats

Page generated in 0.0742 seconds