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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.
21

Aspects of the biological interactions between natriuretic peptides and cultured glial cells /

Yeung, Tok-fai, Vincent. January 1997 (has links)
Thesis (M.D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 246-315).
22

Aspects of the biological interactions between natriuretic peptides and cultured glial cells

Yeung, Tok-fai, Vincent. January 1997 (has links)
Thesis (M.D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 246-315) Also available in print.
23

Cardioversión química temprana en fibrilación auricular: Hospital Militar Central (enero 2000-junio 2002)

Santos Carrasco, Gina January 2003 (has links)
La Fibrilación Auricular constituye la arritmia más frecuente vista en los servicios de emergencia. La amiodarona constituye una estrategia de tratamiento eficaz como cardiovertor químico en la fibrilación auricular, siendo su uso cada vez mayor por sus excelentes cualidades. El propósito del presente trabajo fue evaluar la eficacia de la amiodarona en la cardioversión de arritmias auriculares a ritmo sinusal de reciente inicio. Se estudiaron 40 pacientes ingresados al Servicio de Emergencia del Hospital Militar Central, con diagnóstico de fibrilación auricular de reciente inicio, usando la amiodarona por vía endovenosa, observando una cardioversión química exitosa en el 87.5% de los pacientes, siendo el medicamento bién tolerado, no hallándose efectos adversos o de importancia. Por lo tanto la amiodarona endovenosa constituye un eficaz cardiovertor químico de la fibrilación auricular de reciente inicio respaldado con diversos estudios. Es una droga bien tolerada. / --- Atrial Fibrilation is a frequent arrhytmia. A therapeutic option for this pathology is quimic cardioversion. The objective of this study was to investigate the efficacy of intravenous amiodarona in recent onset atrial fibrilation. We studied 40 patients who where admitted to the emergency department with diagnostic of recent onset atrial fibrillation who recibed intravenous amiodarone. Quimic cardioversion was achieved in 87.5% of them, with good tolerance and side effects presenting in 10 % of the patients. Conclusion: the precocious therapy with intravenous amiodarona as a quimic cardiovertor is effective and well tolerated. Amiodarone is well tolerated as a precocious treatment for quimic cardioversion in patients with atrial fibrillation. / Tesis de segunda especialidad
24

Secretory Control and Renal Actions of ANF in Pregnancy

Javeshghani, Danesh January 1994 (has links)
Note:
25

Relationship between Atrial Natriuetic Factor and the Autonomic Nervous System

Debinski, Waldemar January 1988 (has links)
Note:
26

Characterization of Conduction Abnormalities in Canine Models of Atrial Arrhythmias

Ryu, Kyungmoo 07 April 2005 (has links)
No description available.
27

Symptoms in Adults with Atrial Fibrillation Seeking Care in Emergency Department

Gonia, Regina, Gonia, Regina January 2017 (has links)
Atrial fibrillation is a common arrhythmia encountered in the emergency department. In the United States, newly diagnosed cases of atrial fibrillation is projected to be 2.6 million cases in 2030 and the annual prevalence of atrial fibrillation is expected to be 12.1 million in 2030 (Colilla et al., 2013). Patients may present to the emergency department for treatment of atrial fibrillation with a variety of symptoms and therefore makes diagnosing atrial fibrillation based on symptomatology challenging for the clinician. The primary goal of this Doctor of Nursing Practice (DNP) project is to describe symptoms of atrial fibrillation in patients that seek medical treatment in the emergency department. Methods: This descriptive study contains secondary analysis of existing data derived from structured interviews that took place at two academic medical centers. This analysis included 74 patients that presented to the emergency department with symptoms suspected of acute coronary syndrome and were later diagnosed with atrial fibrillation. Descriptive statistics were used to synthesize data, while inferential statistics (bivariate tests) were used to compare symptoms between the age groups. Results: The mean age of subjects was 70 + 13 years, ranging 31 to 92 years. The majority of subjects were men (75.7%) and whites (90.5%). The most common symptoms reported by study subjects included chest discomfort (n = 50; 67.6%), followed by generalized weakness (n = 39; 52.7%) and shortness of breath (n = 39; 52.7%), and palpitations/ funny beating of the heart (n = 36; 48.6%) and unusual fatigue/ tiredness (n = 36; 48.6%). Sweating was the only symptom that was statistically significant in the younger adult group than in the older adult age group. Conclusion: The symptoms identified in this DNP project can be used to aid in identifying patients that present to the emergency with symptomatic atrial fibrillation. Further efforts for the assessment of atrial fibrillation should focus on the dissemination of common although nonspecific symptoms to facilitate the inclusion of atrial fibrillation as part of the differential diagnosis.
28

Fibrilação atrial e demência: estudo de base populacional no distrito do Butantã, São Paulo / Atrial fibrillation and dementia: a population-based study in the Butantã district, São Paulo

Yoshihara, Liz Andrea Kawabata 06 October 2008 (has links)
INTRODUÇÃO: O aumento da proporção de idosos implica estudar os determinantes dos principais agravos associados ao envelhecimento como a demência, principalmente a associada à doença cerebrovascular. Um fator de risco relevante para doença cerebrovascular é a freqüência de fibrilação atrial crônica. O São Paulo Health and Ageing Study com base populacional para estudo de distúrbio cognitivo e demência é uma oportunidade única para verificar a prevalência de fibrilação atrial e de sua associação com demência. MÉTODOS: Estudo transversal, por arrolamento de 1524 idosos com 65 anos ou mais estudo acima, no distrito do Butantã, cidade de São Paulo. O diagnóstico de fibrilação atrial foi feito com o eletrocardiograma de repouso de doze derivações e o de demência foi feito utilizando-se o protocolo do Research Group of Dementia 10/66. Estudaram-se variáveis sócio-econômicas e fatores de risco cardiovascular como hipertensão, diabetes, dislipidemia e obesidade. RESULTADOS: A amostra estudada tinha idade média de 72,2 anos, era predominantemente feminina, branca, casada, de baixa escolaridade e renda. A prevalência de fibrilação atrial associou-se ao aumento da idade e foi de 1,9% para o sexo feminino e 3,1% para o sexo masculino, com prevalência para ambos os sexos ajustada para idade de 2,7%. A prevalência de demência também se associou ao aumento da idade e sua prevalência idade ajustada foi de 4,9%, maior em mulheres (4,8%) do que em homens (3,6%). A razão de chances ajustada para idade para a associação de fibrilação atrial e demência foi de 2,88 (Intervalo de Confiança, IC 95% - 0,98 8,40) para ambos os sexos sendo e, de 1,50 (IC95% - 0,19 11,83) para homens e 4,48 (IC95% - 1,23 16,29) para mulheres. Encontrou-se maior risco de demência entre mulheres com fibrilação atrial (17,7%) do que entre os participantes do mesmo sexo sem demência (4,6%) Outras alterações no eletrocardiograma de repouso com interesse foram determinadas como com área inativa (código de Minnesotta q1- q2) de: 9,1% nas mulheres e 16,6% nos homens; e também bloqueio de ramo esquerdo de 3,3%, nas mulheres 3,0% e nos homens 3,6%. CONCLUSÃO: Mulheres idosas com fibrilação atrial têm diagnóstico de demência quase quatro vezes mais do que aquelas em ritmo sinusal / INTRODUCTION: The growing aging population proportion makes us study the most important illness related with aging of the population as dementia, specially the dementia associated to stroke. Atrial fibrillation is a main risk factor with cerebrovascular disease. The São Paulo Heath and Ageing Study a population based study for cognitive disturb and dementia is an unique opportunity to verify the atrial fibrillation prevalence and its association with dementia. Methods: This is a cross-sectional study. The population of this study was composed by 1,524 elderly people, over 65 years of age, covered by the Health Program Family in the Butantã district, São Paulo, who were recruited door by door. The diagnosis of atrial fibrillation was made using a twelve lead resting electrocardiogram and the diagnosis of dementia was made by the protocol of Research Group of Dementia 10/66. We studied socio economic variables and cardiovascular risk factors as hypertension, diabetes, dislipidemia and obesity. RESULTS: The studied population had a mean age of 72.2 years old and was predominantly female, white, married and of low educational and financial status. We found that atrial fibrillation prevalence increased throughout age-strata and was of 1.9% among the females and 3.1% among the males, and age-adjusted prevalence of 2.7%. The prevalence of dementia also increases with age and its ageadjusted prevalence was of 4.9%, greater among the females (4.8%) than among the males (3.6%). The odds ratio age-adjusted for the association of atrial fibrillations and dementia was of 2.88 (Confidence interval, 95% CI 0.98 8.40) for both sex: 1.50 among men (95% CI 0.19 11.83), and 4.48 among women (95% CI 1.23 16.29). We found a higher risk of dementia among the female with atrial fibrillation (17.7%) than among female participants without atrial fibrillation (4.6%). Other resting electrocardiogram alterations were determined as previous inactive areas (Minnesotta Code q1-q2) of 12.4%: among the females of 9.1% and among the males of 16.6%. The frequency of left bundle-branch block was of 3.3%: among the females of 3.0% and among the males of 3.6% .CONCLUSION: Elderly women with atrial fibrillation had the diagnosis of dementia almost four times greater than that of women with sinus rhythm
29

Left atrial function in health and disease

Henein, Mark January 2012 (has links)
The Objectives of this thesis are: 1) To study possible atrial interaction in patients with right and left ventricular outflow tract obstruction due to significant pulmonary (PS) and aortic valve stenosis (AS), respectively. 2) To assess left atrial (LA) intrinsic myocardial function and its relationship to indirect measures of left ventricular (LV) filling pressures in patients with paroxysmal atrial fibrillation (PAF). 3) To test the hypothesis that the LA function is affected in patients with pulmonary arterial hypertension (PAH). 4) To test the hypothesis that raised LA pressure as shown by pulmonary capillary wedge pressure (PCWP) correlates with severity of LA intrinsic systolic function. We conducted 4 studies to achieve the objective sabove. Study I Methods: We studied 41 PS patients (age 36±10 year) and 41 AS patients (age 35 ± 12 year) and compared them with 27 controls (age 30 ± 7 year). RV and LV filling were recorded by conventional PW Doppler. Biventricular segmental function was studied using the PW tissue Doppler imaging (TDI) and M mode techniques. Results: The 2 patient groups had similar degree of ventricular outflow tract obstruction. In the pressureoverloaded ventricle, global systolic function was preserved but long axis function was impaired.Patients had higher peak late filling (Awave)and TDI late diastolic (a’) velocities recorded in the disease free ventricles despite having similar peak early filling velocities (E wave), E wave deceleration time and E/e’ ratios were not different from controls (p>0.05 for all). The accentuation of atrial activity (A wave) was moderately correlated with the degree of contra lateral ventricular outflow tract obstruction (p<0.001 for both). Conclusion: In the pressure overloaded ventricle long axis function is more sensitive than global function in revealing myocardial dysfunction. The increased contra lateral atrial systolic activity suggests an evidence for atrial interaction in the form of ‘Cross Talk’. Study II Methods: Twentyfive PAF patients (age 68±7 year, 10 males) with Doppler signs of raised filling pressures were studied using speckle tracking echocardiography and compared with 21 controls. LA segmental longitudinal strain (S), strain rate (SR) and myocardial velocities during atrial systole were measured as were LA longitudinal and transverse diameters. Markers of LV filling pressures were E/A andE/e’. Results: LA longitudinal diameter was larger in patients (5.5±0.6 vs. 4.8±0.6cm,p<0.01) and global LAS and SR were reduced (p<0.05 for both) and correlated with E/A (r=0.52 and r=0.43, p<0.05 for both). LA segmental S and SR were uniformly reduced compared with controls (p<0.05 for all) and also correlated with E/A (p<0.05 for all). LA myocardial velocities (TDI) were highest at the annular level and lowest at the rear in both patients and controls (p<0.01 for all), with the absolute values at each level not different between groups. Myocardial velocities negatively correlated with E/A at the annular level only in patients (septal: r=0.52; lateral: r=0.62, p<0.01 for both). Conclusion: In PAF patients, LA systolic function is suppressed and is directly related to the raised filling pressures. While intrinsic global and segmental function can reproducibly be studied by S and SR, myocardial velocities reflect only regional motion. These findings provide a sound explanation to the known beneficial effect of vasodilators in PAF patients. Study III Methods: We studied LA size and reservoir function in 35 patients (age 63 ± 15 years, 16 male) with idiopathic PAH using speckle tracking echocardiography who also underwent right heart catheterization simultaneously to assess pulmonary artery systolic pressure, and compared them with 27 age and gender normal controls. Results: In PAH patients, LA longitudinal diameter was not different from controls but transverse diameter was reduced (3.0 ± 0.6 vs. 3.7 ± 0.5cm, p<0.001). LA lateral wall strain rate (SR) during LV systole (atrial reservoir function was reduced at annular (p<0.001) and mid cavity (p<0.01) levels as were septal segments (p<0.03, for both) compared to controls. Opposite to controls, the two LA walls responded differently to right heart pressures. Lateral SR inversely correlated with pulmonary artery systolic pressure (PASP) (annular: r=0.45, p<0.005 and midcavity: r=0.43, p<0.01), but not with right atrial pressure (RAP). In contrast, septal SR inversely correlated with RAP (annular: r=0.39, p=0.02 and midcavity: r=0.38, p=0.03) but not with PASP. Conclusion: In patients with PAH, LA reservoir function is significantly impaired showing reduced myocardial strain rate properties. In addition,segmental function differs in their response to raised right heart pressures with the septal wall related to right atrial pressure and lateral wall related to the PASP. These findings suggest an evidence for atrial interaction in PAH, which is likely to have significant impact on LV performance. Study IV Methods: We studied 46 patients, mean age 61 ± 13 years, 17 males, of various etiologies with exertional breathlessness who underwent right heart catheterization and simultaneous transthoracic Doppler echocardiography using spectral, tissue Doppler and speckle tracking echocardiography techniques for assessing LA structure and function. Results: PCWP correlated with direct measurements of LA structure and function: LA volume (r= 0.43, p<0.01), LA global systolic strain rate (r=0.79, p<0.001) and to a lesser extent with LA systolic filling fraction (r=0.52, p<0.001). PCWP also correlated with indirect measures of LA pressure: LV E/A (r=0.66, p<0.001), E wave deceleration time (r=0.54, p<0.001), lateral E/e’ (r=0.49, p<0.001) and LV isovolumic relaxation time (r=0.36, p<0.01). LA strain rate was 78% sensitive and 84% specific in identifying patients with PCWP>15 mmHg, having accurately predicted PCWP in 63% of the cases. Conclusion: PCWP correlates with LA intrinsic systolic function and to a much lesser degree with indirect Doppler measures of raised LV filling pressures. These findings should have significant clinical implications in identifying breathless patients with raised LA pressure.
30

Eventos cardíacos decorrentes da infusão contínua de cloridrato de amiodarona: implicações para o enfermeiro / Cardiac events originated from the continuous infusion of amiodarone hydrochloride: consequences for the nurse

Elbanir Rosangela Ferreira de Sousa 19 February 2014 (has links)
O objeto de estudo são os eventos cardíacos resultantes da infusão contínua de cloridrato de amiodarona em pacientes que evoluíram com fibrilação atrial em pós-operatório de cirurgia cardíaca. Os objetivos foram descrever as características dos pacientes que receberam infusão contínua de cloridrato de amidoarona, apresentar a prevalência de bradicardia e hipotensão encontrada nos pacientes que receberam infusão contínua de cloridrato de amiodarona e discutir as implicações dos achados para a prática dos enfermeiros a partir da prevalência encontrada de bradicardia e hipotensão decorrente da infusão contínua desta substância. Trata-se de um estudo transversal, retrospectivo, documental, por meio de análise de prontuários e avaliação quantitativa dos mesmos. Desenvolvida em uma unidade de pós-operatório de cirurgia cardíaca em um hospital universitário pertencente à rede sentinela no município do Rio de Janeiro. Foi considerado hipotensão em presença de PAS menor que 90 mmHg e bradicardia em presença de frequência cardíaca menor que 60 bpm. As variáveis que caracterizavam a população do estudo e as aferições de pressão arterial e frequência cardíaca foram transcritas para um instrumento de coleta de dados dos anos de 2010 e 2011, gerando 1782 horas de infusão contínua de cloridrato de amiodarona em 27 pacientes cirúrgicos (10,50%). Tratou-se de uma população predominantemente feminina, com idade a cima de 60 anos, período de internação superior a uma semana, apresentava hipertensão arterial prévia (59,26%), era portadora de fibrilação atrial (55,56%) e o diagnóstico cirúrgico de revascularização do miocárdio com circulação extracorpórea foi predominante (70,37%). Os dados mostram que 85,19% dos pacientes eram portadores de pelo menos um fator de risco, 70,37% apresentavam dois fatores de risco e 55,55% apresentavam três fatores de risco para desenvolver fibrilação atrial no pós-operatório de cirurgia cardíaca. Foi encontrada uma prevalência de 85,19% pacientes que apresentaram bradicardia, 66,67% apresentaram hipotensão e 59,26% apresentaram tanto bradicardia como hipotensão. Foram 160 episódios de bradicardia com 6,40 episódios por paciente e 77 episódios de hipotensão com 4,2 por paciente. A bradicardia ocorreu principalmente entre 48 e 72 horas do inicio da infusão. Já a hipotensão aumentou progressivamente nas primeiras 48 horas de infusão. Na presença de bradicardia a intervenção mais frequente foi redução da vazão de amiodarona já na presença de hipotensão, a manutenção de infusão de noradrenalina foi a conduta mais regular. Como estratégia de melhoria para segurança do paciente, foram elaboradas condutas como método de barreira para prevenção de eventos adversos como a bradicardia e hipotensão. Os principais cuidados de enfermagem a serem implementados pelo enfermeiro foram o levantamento de fatores de risco para a fibrilação atrial, a detecção da fibrilação atrial, a manutenção de monitorização cardíaca contínua, aferição horária do ritmo cardíaco e o controle da frequência cardíaca e pressão arterial, objetivando intervir precocemente em presença de hipotensão ou bradicardia. / The subject-matter of the following study is the cardiac events that are consequences from the continuous infusion of amiodarone hydrochloride into patients that developed atrial fibrillation in a postoperative care from a cardiac surgery. The aims of the study are: to describe the characteristics of the patients that received continuous infusion of amiodarone hydrochloride; to present the prevalence of bradycardia and hypotension in the patients that received continuous infusion of amiodarone hydrochloride; and to discuss the implications of the findings for the practice of nurses from the prevalence of bradycardia and hypotension that stemmed from the continuous infusion of amiodarone hydrochloride. This is a cross-sectional, retrospective, documentary study through the analysis and quantitative evaluation of medical records. It was developed in a cardiac surgery postoperative unit in a university hospital that belongs to the Rede Sentinela in the City of Rio de Janeiro. Hypotension was defined as the presence of a systemic arterial blood pressure (ABP) lower than 90 mmHg and bradycardia as the presence of a heart rate below 60 bpm. The variables that characterized the population of the study and the measuring of arterial blood pressure and heart rate were transcribed into a data collection instrument through the years 2010 and 2011, creating 1782 hours of continuous infusion of amiodarone hydrochloride into 27 surgical patients (10,50%). The population of the study was mainly composed of women over 60 years old, with an admission over a week period, they showed pre-existing arterial hypertension (58,26%) and have atrial fibrillation (55,56%) and the surgical diagnosis of myocardium revascularization with extracorporeal circulation was predominant (70,37%). The data showed that 85,19% of the patients were carriers of at least one risk factor, 70,37% showed two risk factors and 55,55% showed three risk factors to develop atrial fibrillation in the postoperative of a cardiac surgery. It was found a predominance of 85,19% patients that showed bradycardia, 66,67% showed hypotension and 59,29% showed bradycardia as well as hypotension. There were 160 bradycardia episodes in a rate of 6,40 episodes per patients and 77 hypotension in a rate of 4,2 episodes per patients. The bradycardia happened mainly between the 48 and 72 hours after the infusion. Now, the hypotension increased progressively in the first 48 hours after the infusion. In the presence of bradycardia the medical intervention most frequent was the reduction of the amiodarone flow rate, while in the presence of hypotension the continuity of the norepinephrine infusion was the most common conduct. As strategy to improve the patient safety, conducts were devised as barrier method to prevent adverse events such as the bradycardia and hypotension. The main nursing care implemented by the nurse were the survey of risk factors to the atrial fibrillation, the detection of atrial fibrillation, the continuity of the continuous cardiac monitoring, hourly measuring of the heart rate and the control of the heart rate and arterial blood pressure, in order for a earlier medical intervention in the presence of hypotension or bradycardia.

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