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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.
161

Caracterização fenotípica do camundongo BALB/c mutante anêmico / Phenotype characterization of anemic mutant BALB/c mouse

Miyashiro, Samantha Ive 28 September 2012 (has links)
Várias linhagens de camundongos resultam de mutações genéticas pontuais espontâneas ou induzidas e estas alterações podem apresentar fenótipos relevantes semelhantes a doenças hereditárias humanas. Massironi et al. (2006) desenvolveram vários camundongos BALB/c mutantes com o agente mutagênico etil-nitroso-uréia (ENU) no Biotério de Experimentação do Departamento de Imunologia do Instituto de Ciências Biomédicas (ICB) da Universidade de São Paulo. Destes, o mutante chamado anêmico foi objeto de estudo desta pesquisa, que tem como objetivo a sua fenotipagem. A avaliação hematológica revelou moderada anemia com intensa policromasia e reticulocitose, acompanhada de anisocitose, macrocitose, hipocromia, inclusões intraeritrocíticas e corpúsculos de Heinz, do nascimento até 18 meses de idade. Apresentaram também hemoglobinúria, bilirrubinemia, hiperfosfatemia e populações eritrocíticas com diferentes resistências à lise osmótica. No estudo da hemoglobina, não foi possível distinguir Hb anormal pela eletroforese em acetato-celulose em pH alcalino, ou cadeia globínica diferente pela eletroforese de cadeias globínicas em pH alcalino, mas constatou-se precipitação da hemoglobina no teste de estabilidade térmica e no teste de isopropanol. Na necrópsia, observou-se intensa esplenomegalia, especialmente nas fêmeas de 12 a 18 meses de idade, discreta hepatomegalia, moderada cardiomegalia e icterícia subcutânea. No exame histopatológico, observou-se intenso aumento da hematopoiese e hemossiderose nos órgãos hematopoiéticos e nas células tubulares renais notou-se deposição de ferro intracitoplasmático e houve aumento da concentração de creatinina plasmática animais mais idosos. Estes dados permitem classificar o quadro como anemia hemolítica congênita regenerativa crônica, semelhante a quadros de anemia por hemoglobina instável, descritos para humanos. Massironi (dados não publicados) concluiu o mapeamento genético deste mutante, que revelou a troca de aminoácidos na posição 88 da cadeia beta da hemoglobina (leucina por prolina), devido à troca de T por C no gene da globina β Hbb-b1 no cromossomo 7, que corresponde à mutação da hemoglobina de Santa Ana descrita em humanos. A Hb Santa Ana é uma hemoglobina instável rara, com descrição de casos no Brasil, EUA, França, Hungria e Japão e que resulta em importante anemia hemolítica congênita crônica com evidente esplenomegalia. Este camundongo BALB/c mutante anêmico apresenta fenótipo e genótipo muito similares ao quadro de hemoglobina instável de Santa Ana e, considerando-se a importância dos modelos animais para o avanço dos estudos de doenças humanas, este modelo seria o primeiro camundongo mutante descrito para o estudo desta doença. / Many strains of mice result from spontaneous or induced punctual genetic mutations and these changes may present relevant and similar phenotypes to inherited human diseases. Massironi et al. (2006) developed some BALB/c mice mutants with the mutagen ethyl-nitroso-urea (ENU) in the Biotério de Experimentação, Departamento de Imunologia, Instituto de Ciências Biomédicas (ICB) of Universidade de São Paulo. From these, the mutant called anemic is the object of this research, which aims to characterize its phenotype. The hematologic evaluation revealed moderate anemia with intense reticulocytosis and polychromasia, followed by anisocytosis, macrocytosis, hypochromia and intraerythrocytic inclusion and Heinz bodies, presented from birth to 18 months of age. They also presented hemoglobinuria, bilirrubinaemia, hyperfosfatemia, and erythrocytic populations with different resistance to osmotic lysis. In the hemoglobin study, it was not possible to distinguish an abnormal Hb by cellulose acetate electrophoresis at alkaline pH nor a different globin chain with globin chains electrophoresis at alkaline pH, but there was hemoglobin precipitation at heat stability test and isopropanol test. At necropsy, there was evident splenomegaly - especially within the 12 to 18 months old mutant female group, discrete hepatomegaly, moderate cardiomegaly, and subcutaneous jaundice. On histopathologic examination, there was dramatic increase in the hematopoiesis and hemosiderosis in hematopoietic organs and intracellular iron deposition on tubular renal cells with elevated plasma creatinin concentration in the oldest animals. These data indicate a congenital hemolytic regenerative anemia, similar to human unstable hemoglobin anemia. By genetic mapping concluded by Massironi (data not published), it has been detected an amino acid exchange (leucine to proline) at position 88 in the beta globin protein, because of a T to C change in β globin gene Hbb-b1 on chromosome7, which corresponds to the Santa Ana hemoglobin mutation described in humans. Hb Santa Ana is a rare unstable hemoglobin reported in Brazil, USA, France, Hungary and Japan, that presents cronic congenital hemolytic anemia with evident splenomegaly. This BALB/c mutant mouse presents similar genotype and phenotype to the human Santa Ana unstable hemoglobin. Considering the importance of animal models for human diseases studies advance, this model would be the first mutant mouse described for study of Hb Santa Ana.
162

Mouse model of Cooley's anemia

Huo, Yongliang. January 2009 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed on July 13, 2010). Includes bibliographical references.
163

In Vivo Tissue Diagnosis for Myocardial Infarction Using Optical Spectroscopy with Novel Spectral Interpretation Algorithms

Chen, Po-Ching 31 March 2011 (has links)
In recent decades, the rapid development of optical spectroscopy for tissue diagnosis has been indicative of its high clinical value. The goal of this research is to prove the feasibility of using diffuse reflectance spectroscopy and fluorescence spectroscopy to assess myocardial infarction (MI) in vivo. The proposed optical technique was designed to be an intra-operative guidance tool that can provide useful information about the condition of an infarct for surgeons and researchers. In order to gain insight into the pathophysiological characteristics of an infarct, two novel spectral analysis algorithms were developed to interpret diffuse reflectance spectra. The algorithms were developed based on the unique absorption properties of hemoglobin for the purpose of retrieving regional hemoglobin oxygenation saturation and concentration data in tissue from diffuse reflectance spectra. The algorithms were evaluated and validated using simulated data and actual experimental data. Finally, the hypothesis of the study was validated using a rabbit model of MI. The mechanism by which the MI was induced was the ligation of a major coronary artery of the left ventricle. Three to four weeks after the MI was induced, the extent of myocardial tissue injury and the evolution of the wound healing process were investigated using the proposed spectroscopic methodology as well as histology. The correlations between spectral alterations and histopathological features of the MI were analyzed statistically. The results of this PhD study demonstrate the applicability of the proposed optical methodology for assessing myocardial tissue damage induced by MI in vivo. The results of the spectral analysis suggest that connective tissue proliferation induced by MI significantly alter the characteristics of diffuse reflectance and fluorescence spectra. The magnitudes of the alterations could be quantitatively related to the severity and extensiveness of connective tissue proliferation.
164

Resuscitation From Severe Hemorrhagic Shock After Traumatic Brain Injury Using Saline, Shed Blood, or a Blood Substitute

Gibson, Jeffrey B., Maxwell, Robert A., Schweitzer, John B., Fabian, Timothy C., Proctor, Kenneth G. 01 January 2002 (has links)
The original purpose of this study was to compare initial resuscitation of hemorrhagic hypotension after traumatic brain injury (TBI) with saline and shed blood. Based on those results, the protocol was modified and saline was compared to a blood substitute, diaspirin cross-linked hemoglobin (DCLHb). Two series of experiments were performed in anesthetized and mechanically ventilated (FiO2 = 0.4) pigs (35-45 kg). In Series 1, fluid percussion TBI (6-8 ATM) was followed by a 30% hemorrhage. At 120 min post-TBI, initial resuscitation consisted of either shed blood (n = 7) or a bolus of 3x shed blood volume as saline (n = 13). Saline supplements were then administered to all pigs to maintain a systolic arterial blood pressure (SAP) of >100 mmHg and a heart rate (HR) of <110 beats/min. In Series 2, TBI (4-5 ATM) was followed by a 35% hemorrhage. At 60 min post-TBI, initial resuscitation consisted of either 500 mL of DCLHb (n = 6) or 500 mL of saline (n = 5). This was followed by saline supplements to all pigs to maintain a SAP of >100 mmHg and a HR of <110 beats/min. In Series 1, most systemic markers of resuscitation (e.g., SAP, HR, cardiac output, filling pressures, lactate, etc.) were normalized, but there were 0/7 vs. 5/13 deaths within 5 h (P = 0.058) with blood vs. saline. At constant arterial O2 saturation (SaO2), mixed venous O2 saturation (SvO2), cerebral perfusion pressure (CPP), and cerebral venous O2 saturation (ScvO2) were all higher, intracranial pressure (ICP) was lower, and CO2 reactivity was preserved with blood vs. saline (all P < 0.05). In Series 2, SAP, ICP, CPP, and lactate were higher with DCLHb vs. saline (all P < 0.05). Cardiac output was lower even though filling pressure was markedly elevated with DCLHb vs. saline (both P < 0.05). Neither SvO2 nor cerebrovascular CO2 reactivity were improved, and ScvO2 was lower with DCLHb vs. saline (P < 0.05). All survived at least 72 h with neuropathologic changes that included sub-arachnoid hemorrhage, midline cerebellar necrosis, and diffuse axonal injury. These changes were similar with DCLHb vs. saline. Thus, whole blood was more effective than saline for resuscitation of TBI, whereas DCLHb was no more, and according to many variables, less effective than saline resuscitation. These experimental results are comparable to those in a recent multicenter trial using DCLHb for the treatment of severe traumatic shock. Further investigations in similar experimental models might provide some plausible explanations why DCLHb unexpectedly increased mortality in patients.
165

Oxygenation of Solid Tumor Tissue Facilitated by Polymerized Human Hemoglobins

Belcher, Donald Andrew 30 September 2019 (has links)
No description available.
166

Methemoglobin Formation via Nitric Oxide and Comparison of Methemoglobin, Deoxyhemoglobin, and Ferrous Nitrosyl Hemoglobin as Potential MRI Contrast Agents

Ayati, Roya 13 December 2022 (has links)
Gadolinium-based contrast agents (GBCAs) are in widespread use to enhance magnetic resonance angiography images for evaluating vascular pathology. However, there are safety concerns and limitations regarding the use of GBCAs. It has been shown that the magnetic resonance imaging (MRI) signal intensity (T1-weighted images) in some of the brain's tissues is higher for patients who had multiple exposures to GBCAs compared to patients who had never had exposure to GBCAs. This implies that GBCAs are not sufficiently removed from body such that GBCAs may potentially have long-term effects on the human body. These potential safety concerns have led to an increased interest in alternative contrast agents. Methemoglobin (metHb) and oxygen-free hemoglobin (HHb) are two forms of hemoglobin with paramagnetic properties. It has been shown that the T1-weighted signal intensity of blood is changed during MRI scans for metHb and HHb, leading to enhanced contrast of MRI images. The ability of metHb and HHb to change the signal intensity has led to the idea that they can be used as effective contrast agents. MetHb can be made by exposing oxyhemoglobin (oxyHb) to nitric oxide (NO) and HHb can be made by removing the oxygen from hemoglobin using nitrogen (N2). In this study, a new gas delivery system was developed to make metHb and HHb. The new gas delivery system was developed to have greater experimental control compared to the PermSelect hollow-fiber module that was used in preliminary studies to make metHb. The same system can be used to make HHb. Initial experiments showed significant amounts of undesired nitrite (NO2-) formation during metHb formation due to the presence of contaminants in the NO gas source. To minimize this problem, flow of NO from the gas source was bubbled in a sodium hydroxide solution in order to reduce the NO2- concentration. Following metHb formation, continuous delivery of NO also led to the formation of ferrous nitrosyl hemoglobin (HbIINO). MRI studies showed that HbIINO can also increase the signal intensity of an MRI image. It is unknown as to whether metHb, HHb, or HbIINO would be a stronger and more appropriate contrast agent and to what extent the T1-weighted signal is affected by the concentration. This study evaluated T1-weighted images of blood samples over a range of metHb and HHb concentrations, as well as HbIINO concentrations. Comparison of T1 values showed that metHb is the strongest contrast agent and that HHb is a relatively weak contrast agent. This study showed for the first time that HbIINO can provide a contrast effect, although not as strong as metHb but stronger than HHb. With metHb providing a viable contrast between 10-20%, metHb has the potential to be a safe and effective contrast agent since it can be naturally converted back to hemoglobin.
167

SYNTHESIS, TESTING AND CRYSTALLOGRAPHIC STUDIES OF ALLOSTERIC MODIFIERS OF HEMOGLOBIN

Deshpande, Tanvi 05 July 2013 (has links)
The major physiological function of hemoglobin (Hb) is to bind, transport and deliver oxygen to tissues; made efficient by endogenous effectors, such as protons and 2,3-diphosphoglycerate. Synthetic allosteric effectors of Hb (AEHs) are also known to modulate Hb oxygen affinity, showing potential for the treatment of sickle cell disease (SCD) and ischemic-related diseases. In this project, AEHs which increase Hb affinity for oxygen, including derivatives of the anti-sickling compounds, 5HMF and benzaldehydes, as well as an AEH that decreases Hb affinity for oxygen, RSR-13, were synthesized for their effects on Hb oxygen binding property and their capability to release NO from substituted nitrate ester moieties. Compounds that were found to increase Hb affinity for oxygen were further tested for their anti-sickling activities. Structural studies were carried out to gain insight into the compound’s mode of action. Development of these agents could be a therapeutic strategy for SCD or ischemic-related diseases.
168

Biomarkery v diagnostice a terapii pozdních komplikací diabetu. / Biomarkers in the diagnosis and treatment of diabetic complications

Šoupal, Jan January 2017 (has links)
The main objective of this study was research on biomarkers used in both diagnosis and therapy of diabetic complications. The main focus of our work came to be on one of these biomarkers - glycemic variability (GV). High GV is linked with more frequent occurance of hypoglycemia. There are even indications it might contribute to development of diabetic complications. With modern technology - continuous glucose monitoring (CGM), we are now able to reliably describe, calculate and reduce GV. So far it is unclear whether increased GV can contribute to the development of microvascular complications (MVC) in type 1 diabetes (T1D). Studies published so far have assessed GV primarily from routine self-monitoring of blood glucose (SMBG) using glucometers. In the light of this uncertaity, the first part of this work compares GV calculated from CGM with the presence of MVC in T1D patients. GV calculated from CGM, but not from SMBG, proved to be significantly higher in T1D patients with MVC, even though there was no significant difference in glycated hemoglobin (HbA1c). This finding supports the hypothesis that higher GV is related to higher risk of MVC and that HbA1c does not describe diabetes control completely. Moreover, it was shown that GV calculated from SMBG is insufficient. There is still no fully...
169

Vliv pravidelné pohybové aktivity na dlouhodobou kompenzaci diabetu mellitu 1. typu / The effect of regular physical activity on a long-term control of Type 1 Diabetes Mellitus

Schöppelová, Lucie January 2018 (has links)
Introduction: Physical activity should be part of our everyday life. However, for people with Type 1 Diabetes Mellitus it is the most common cause of hypoglycemia. To control diabetes in the right way, it is therefore necessary to follow certain rules and recommendations that help preventing hypoglycemia while the physical activity remains beneficial at the same time. Aim of the work: The main aim of this study is to clarify the influence of physical activity in connection to long-term control of Type 1 Diabetes Mellitus. Methods: 102 respondents with diagnosed Type 1 Diabetes Mellitus in the age of 19-69 years participated in a quantitative analysis. This research was conducted in a form of multicentric examination at two independent medical centers. The data collection was done through questionnaires focused on physical activity and daily regime. The data from questionnaires were then compared to the values of glycated hemoglobin (HbA1C), HDL cholesterol and the total daily dose of insulin of certain patients. For statistical evaluation, analytical tools of Microsoft Office program were used (F-test and t-test). Results: We found correlation between HbA1C values in patients physically active for less than 2 hours/week compared to those who are physically active for more than 2 hours/week (62,72...
170

Pohybová edukace u jedinců s diabetes mellitus 2.typu / Physical activity education of individuals with type 2 diabetes

Ludvíčková, Dana January 2020 (has links)
Title: Physical education of individuals with type 2 diabetes mellitus Objectives: The aim of this thesis is to evaluate the effect of physical education of individuals with type 2 diabetes mellitus cured in diabetologic outpatient clinic of Genereal University Hospital in Prague. The physical education was focused on nordic walking. Methods: Eight patients of diabetological outpatient clinic were chosen by the doctor for this survey. The physical examination was carried out with seven patients. It involved anthropometrical measurements (weight, waist circumference) and blood collection for biochemical parameters assessment (glycemia, glycated hemoglobin). Two-minute step test was chosen for assessment of subject's physical fitness. Results: The physical activity education of individuals with type 2 diabetes mellitus doesn't increase the amount of their physical activity. The physical activity of type 2 diabetes mellitus individuals is rather low as well as their exercise adherence. Nordic walking exercise program can improve anthropometrical parametres (weight, waist circumference) and can reduce HbA1c levels. Lower health-related quality of life in physical and physological aspects wasn't proved in type 2 diabetes patients. Key words: nordic walking, physical activity, type 2 diabetes management,...

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