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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.
91

Alterações cardiovasculares induzidas pela administração aguda e crônica do protótipo de fármaco LQFM-21 / Cardiovascular changes induced by acute and administration and drug prototype chronic LQFM -21

Trindade, Neidiane Rosa 26 February 2015 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2016-03-03T18:02:47Z No. of bitstreams: 1 Dissertação - Neidiane Rosa Trindade - 2015.pdf: 2000025 bytes, checksum: 6494e8ba940637606f17c94047484721 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2016-03-03T19:05:36Z (GMT) No. of bitstreams: 1 Dissertação - Neidiane Rosa Trindade - 2015.pdf: 2000025 bytes, checksum: 6494e8ba940637606f17c94047484721 (MD5) / Made available in DSpace on 2016-03-03T19:05:36Z (GMT). No. of bitstreams: 1 Dissertação - Neidiane Rosa Trindade - 2015.pdf: 2000025 bytes, checksum: 6494e8ba940637606f17c94047484721 (MD5) Previous issue date: 2015-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed to investigate the effects hypotensive (LQFM-21), trying to identify a pharmaceutical potential for this new drug prototype. Male Wistar spontaneous hypertensive rats (SHR) and wistar rats were used to evaluate the effect of LQFM-21 on mean arterial pressure (MAP), heart rate (HR), renal vascular conductance (RVC), arterial vascular conductance (CVA) and baroreflex sensitivity index (BI). The administration of LQFM-021 (0.05, 0.1, 0.2, 0.4 mg / kg, iv.) Decreased MAP (-9.0 ± 1.4, -21.5 ± 2.9, ± 2.8 - 26.7 mmHg respectively); increased RVC (12.0 ± 1.9, 23.2 ± 3.2, 26.8 ± 6.3, 34.8 ± 5.9%, respectively) and CVA (17.3 ± 1.7; 27 8 ± 2.6, 32.7 ± 4.8 and 42.2 ± 3.4%, respectively) in anesthetized normotensive rats. In SHR, also found reduction of MAP (-16.9 ± 2.8; -19.4 ± 2.5; -22.0 ± 3.8 -17.2 ± 6.4 mmHg, respectively), HR (-11.2 ± 0.8 bpm at a dose of 0.04 mg / kg) and an increase in RVC (22.2% at a dose of 0.2 mg / kg) and CVA (12.2 (12.2 ± 2.1, 13.8 ± 5.6, 18.2 ± 2.3, 15.6 ± 3.1% at doses of 0.05, 0.1, 0.2, 0.4 mg / kg, respectively). Both the acute, oral as the oral administration chronicle of LQFM-21 at a dose of 15 mg / kg reduced the MAP in animals wistar 89.9 ± 1.9 mmHg and 136.4 ± 4.9 mmHg SHR without changing BI in wistar animals with the infusion of phenylephrine -2.3 ± 0.32 vs 1.9 ± 0.1 mmHg / bpm and SHR -1.9 ± 0.2 vs. -1.9 ± 0.3 mmHg / bpm, with infusion nitroprusside in wistar 3.2 ± 0.31 vs 3.0 ± 0.04 bpm / mmHg and 3.9 ± 0.6 vs SHR 3.0 ± 0.04 bpm / mmHg. Together our results demonstrated hypotensive effects of LQFM- 21. However further studies are needed to identify the mechanism of action and toxicity of this drug prototype. / O presente estudo buscou investigar os efeitos hipotensores do (LQFM-21), tentando identificar um potencial farmacêutico para este novo protótipo de fármaco. Ratos Wistar ou espontaneamente hipertensos (SHR) foram utilizado para avaliar o efeito de LQFM-21 sobre a pressão arterial média (PAM), frequência cardíaca (FC), condutância vascular renal (CVR), condutância vascular arterial (CVA), e índice sensibilidade do barorreflexo (IB). A administração do LQFM-021 nas doses (0,05, 0,1, 0,2, 0,4 mg / kg, iv.) reduziu PAM (-9,0 ± 1,4, -21,5 ± 2,9, -26,7 ± 2,8 mmHg, respectivamente); aumentou CVR (12,0 ± 1,9; 23,2 ± 3,2; 26,8 ± 6,3; 34,8 ± 5,9%, respectivamente) e CVA (17,3 ± 1,7; 27,8 ± 2,6; 32,7 ± 4,8 e 42,2 ± 3,4%, respectivamente) em ratos normotensos anestesiados. Em SHRs, também encontramos redução da PAM (-16,9 ± 2,8; -19.4 ± 2.5; -22,0 ± 3,8; -17,2 ± 6,4 mmHg, respectivamente), FC (-11,2 ± 0,8 bpm na dose de 0,04 mg / kg) e aumento na CVR (22,2% na dose de 0,2 mg / kg) e CVA (12,2 (1 2,2 ± 2,1, 13,8 ± 5,6, 18,2 ± 2,3, 15,6 ± 3,1%, na doses de 0,05; 0,1; 0,2; 0,4 mg / kg, respectivamente). Tanto a administração oral aguda, como a crônica de LQFM-21 na dose de 15 mg / kg reduziu a PAM nos animais normotensos 89,9 ± 1,9 mmHg e SHR 136,4 ± 4,9 mmHg sem alterar IB nos animais Wistar com a infusão da fenilefrina -2,3 ± 0,32 vs -1,9 ± 0,1 mmHg/bpm e SHR -1,9 ± 0,2 vs -1 ,9 ± 0,3 mmHg/bpm, com infusão de nitroprussiato em Wistar 3,2 ± 0,31 vs 3,0 ± 0,04 bpm/ mmHg e SHR 3,9 ± 0,6 vs 3,0 ± 0,04 bpm / mmHg. Em conjunto nossos resultados demonstraram o efeito hipotensor do LQFM-21 . Entretanto novos estudos precisam ser realizados para identificarmos o mecanismo de ação e toxicidade deste protótipo de fármaco.
92

Estudo da ação cardiovascular de extratos padronizados das folhas de Quassia amara L. (pau-amargo) coletadas em Manicoré, na Amazônia Ocidental

Retroz, Francianny Carla Moraes 25 June 2012 (has links)
Made available in DSpace on 2015-04-11T13:38:25Z (GMT). No. of bitstreams: 1 francianny.pdf: 1582573 bytes, checksum: 107d67128bf43813bf5591f4c2d0e26f (MD5) Previous issue date: 2012-06-25 / Quassia amara L. (Simaroubaceae) is a pan american plant known as pau amargo and quassia. It is used in the folk medicine to treat gastrointestinal disorders, hypertension, malaria, and as insecticide and vermifuge. Several compounds were isolated from the plant leaves and barks as β-carbonile alkaloids, 6-cantin, steroids and quassinoids (neoquassin and quassin). In this work, the effects of the standardized extracts from Q. amara collected in Manicoré/AM were studied on the cardiovascular system of rodents. The aqueous extract (AE) was prepared from the dried leaves infusion and the butanolic fraction (BuF) was obtained from the AE partition in butanol. The BuF standardization and purification in HPLC isolated 6 fractions (F1 to F6). The AE oral administration (1.0 g/kg) did not produce evident signals of pharmacological activity in rats; BuF caused sedation, anesthesia and cyanosis after 1 h. Death was not observed after 24 h of the treatment. However, BuF (1.0 g/kg) intraperitoneal administration produced intense sedation, anesthesia and cyanosis after 1 h of the treatment; all animals died after 2 h. In anesthetized rats, BuF produced fast and transient hypotension, without altering the hypertensive effect of noradrenalin, or the hypotension induced by acetylcholine. The hypotension caused by BuF (10.0 mg/kg, e.v.) was unchanged by previous treatment with atropine or prazosin. The fractions responsible for the hypotensive effect were: F1, F3 and F6. All fractions were tested on intact endothelium- and denuded- aorta rings contracted by noradrenalin. F1, F3, F4, F5 and F6 fractions relaxed the endothelium intact aorta tonus, indicating a mechanism dependent on NO cascade. The chronotropic and inotropic effects of AE and BuF were also evaluated in isolated right and left rat atrium. Neither AE (30 to 300 μg/mL) nor BuF (10 to 100 μg/mL) alter the chronotropism, however, the force of contraction increased in a concentration dependent manner. BuF potentiated the diaphragm muscle contraction induced by direct and indirect electrical stimulation. BuF (1 to 300 μg/mL) inhibited the activity of the Ca2+-ATPase isolated from rabbit skeletal muscle; this enzyme inhibition may be related to the potentiation of the diaphragm contraction. In rat vas deferens preparations, BuF inhibited the maximal contraction induced by noradrenalin without affecting the drug affinity to the α1-adrenergic receptors. The purified fractions responsible for this effect were F1, F3, F4 e F5. BuF did not inhibit the calcium influx in cardiomyocytes and cultured rat uterus cells. / A Quassia amara L. (Simaroubaceae) é planta pan-americana conhecida como pau-amargo e quassia. É utilizada na medicina popular para o tratamento de distúrbios gastrintestinais, hipertensão, malária, e também como inseticida e vermífuga. Das folhas e cascas foram isolados vários compostos químicos como alcaloides β-carbonila, 6-cantin, esteroides e quassinoides (neoquassina e quassina). Neste trabalho, foram estudados a farmacologia geral e os efeitos no sistema cardiovascular de roedores de extratos padronizados de Quassia amara coletada em Manicoré, AM. O extrato aquoso (EA) foi obtido por infusão de folhas secas, e a fração butanólica, por partição do EA em butanol. A padronização e purificação da FBut por cromatografia líquida de alta eficiência (CLAE) levou ao isolamento de 6 frações (F1 a F6). A administração oral do EA (1,0 g/kg) não produziu sinais evidentes de atividade farmacológica em ratos; a FBut produziu sinais de sedação, anestesia e cianose após 1 h. Não houve morte dos animais após 24 h do tratamento. No entanto, a administração da FBut (1,0 g/kg) por via intraperitoneal produziu sinais de sedação, anestesia e cianose intensos após 1 h de tratamento; todos os animais morreram após 2 h. Na pressão arterial em ratos anestesiados, a FBut produziu hipotensão rápida e passageira, sem alterar o efeito hipertensor da noradrenalina, ou a hipotensão produzida pela acetilcolina. A hipotensão provocada pela FBut (10,0 mg/kg, e.v.) também não foi alterada pelo tratamento prévio do animal com atropina ou prazosin. As frações responsáveis pela ação hipotensora são a F1, F3 e F6. As frações foram testadas em preparações de aorta de rato com e sem endotélio. As frações F1, F3, F4, F5 e F6 relaxaram o tônus muscular da aorta dependente de endotélio, indicando um provável mecanismo via cascata do NO. As atividades cronotrópica e inotrópica do EA e da FBut foram avaliadas em preparações de átrios direito e esquerdo isolados de rato. O EA (30 a 300 μg/mL) e a FBut (10 a 100 μg/mL) não alteraram o cronotropismo, no entanto, aumentaram o inotropismo de maneira concentração-dependente. A FBut potenciou a contração do músculo diafragma de rato sob estímulo direto e indireto. A FBut (1 a 300 μg/mL) inibiu a atividade da Ca2+-ATPase de músculo esquelético de coelho; essa inibição pode estar relacionada à potenciação da contração do músculo diafragma. Em ducto deferente de rato, a FBut diminuiu a contração máxima produzida pela noradrenalina sem alterar a afinidade da droga pelos receptores α1-adrenérgicos. As frações purificadas responsáveis por este efeito foram as F1, F3, F4 e F5. A FBut não inibiu o influxo de cálcio
93

Indices de la réponse au remplissage vasculaire chez les patients ventilés par pression positive

Bendjelid, Karim 09 July 2008 (has links) (PDF)
Ce travail étudie l'estimation de la réponse au remplissage vasculaire (RRV) des patients de soins intensifs ventilés par pression positive. Il propose des paramètres qui sont à même de déterminer, avant l'administration intraveineuse d'un soluté de remplissage si ce dernier a une chance raisonnable d'augmenter le débit cardiaque. A ce jour, les indices statiques n'ont pas fait la preuve de leur utilité pour prédire la RRV chez ce type de patients. A l'opposé, des indices dits dynamiques, se sont avéré précieux pour quantifier la RRV.<br> <br>Dans la première partie de ce travail nous exposons dans nos travaux que les indices dynamiques prédisent la RRV mieux que les indices statiques chez ce type de patients. <br><br>Dans la seconde et dernière partie, et à travers des études animales, nous mettons en évidence que ces mêmes indices ne prédisent pas la RRV en toutes situations. En effet, certains de ces marqueurs peuvent être décevants dans certaines conditions comme l'hypertension abdominale et/ou le SDRA ventilé de manière protectrice.
94

Effects of the NO donors Sodium Nitroprusside andS-nitrosoglutathione on oxygen consumption and embryonic organ growth in the domestic broiler chicken,Gallus gallus domesticus.

Ekström, Andreas January 2010 (has links)
<p>Nitric oxide (NO) is an important chemical factor that controls vascular tone in the cardiovascular system. NO is a vasodilatory molecule that plays a role in blood pressure and blood flow regulation as well as vessel formation and tissue cell proliferation. NO influences the flow by which nutrients and other metabolites required for growth are transported to the tissues. The aim of this study was to investigate if NO, through mediation by the NO donors Sodium Nitroprusside (SNP) and S-Nitrosoglutathione (GSNO) affect growth and oxygen consumption of prenatal broiler chicken. The results indicate that, although the treatments did not have clear significant effects on the embryos or the organs examined, a slight delay in development can be observed in the GSNO treatment embryos. The study could not conclude, however, if this was due to effects of NO donors</p>
95

Cardiovascular Response to Dynamic Functional Electrical Stimulation during Head-up Tilt

Yoshida, Takashi 31 December 2010 (has links)
Orthostatic hypotension (OH) is a prevalent condition among individuals with spinal cord injury (SCI). After an injury, OH often reduces the benefit of neurorehabilitation and also prolongs periods of inactivity that lead to secondary complications. This study investigated whether the cardiovascular response to head-up tilting can be improved using functional electrical stimulation (FES) and rhythmic passive movements of the lower extremities. Participants with high thoracic and cervical SCI were recruited. While the participants were tilted head-up to 70 degrees, four conditions were applied in a random sequence: 1) no intervention, 2) rhythmic passive leg movements, 3) isometric FES, and 4) a combination of FES and passive leg movements. The measured cardiovascular parameters indicated that a combination of FES and passive leg movements induced the most desirable response to head-up tilting. The proposed intervention will enable more individuals with SCI to participate in beneficial neurorehabilitation that uses a novel tilt table.
96

Cardiovascular Response to Dynamic Functional Electrical Stimulation during Head-up Tilt

Yoshida, Takashi 31 December 2010 (has links)
Orthostatic hypotension (OH) is a prevalent condition among individuals with spinal cord injury (SCI). After an injury, OH often reduces the benefit of neurorehabilitation and also prolongs periods of inactivity that lead to secondary complications. This study investigated whether the cardiovascular response to head-up tilting can be improved using functional electrical stimulation (FES) and rhythmic passive movements of the lower extremities. Participants with high thoracic and cervical SCI were recruited. While the participants were tilted head-up to 70 degrees, four conditions were applied in a random sequence: 1) no intervention, 2) rhythmic passive leg movements, 3) isometric FES, and 4) a combination of FES and passive leg movements. The measured cardiovascular parameters indicated that a combination of FES and passive leg movements induced the most desirable response to head-up tilting. The proposed intervention will enable more individuals with SCI to participate in beneficial neurorehabilitation that uses a novel tilt table.
97

Hypotensive resuscitation versus standard fluid resuscitation for the management of trauma patients in hemorrhagic shock : the safety phase of a randomized controlled trial.

Morrison, C. Anne. Horwitz, Irwin, Hwang, Lu-Yu, January 2009 (has links)
Source: Masters Abstracts International, Volume: 47-06, page: 3510. Adviser: Irwin B. Horwitz. Includes bibliographical references.
98

Neuroprotection with Anesthetics in Two Models of Cerebral Ischemia

Chaparro-Buitrago, Rafael Eduardo 16 April 2010 (has links)
Neuroprotection with anesthetics has been studied for many decades; important advances in this field have modified the way Anesthesiologists treat patients in the operating room. Animal models have played an important role in the study of ischemia in the operating room. Recent studies have demonstrated that the effect of anesthetics seems to be different in different animal models. We decided to evaluate anesthetics in a well-known model of cerebral ischemia and also in hypotensive models designed by us. We used a model of cerebral ischemia (MCAO) to test anesthetics neuroprotective effect in a two-week period. Then, we used a model of hypotension to characterize the damage caused by this type of insult. Finally we characterized a model of hypotension plus hypoxia that can mimic real situations in the OR. We found that anesthetics alone do not have a neuroprotective effect after two weeks in the MCAO model; but the combination of anesthetics with caspase inhibitors can decrease the damage caused by ischemia. The caspase inhibitor by itself did not show a significant neuroprotective effect. We also found that repetitive periods of profound hypotension can cause important damage in the hippocampus but no memory or neurological changes were seen. The induction of only one episode of hypotension plus hypoxia did not alter the morphology of the hippocampus although induced memory changes that were reverted by the use of anesthetics.
99

The relation of blood pressure to dementia in the elderly : a community-based longitudinal study /

Qiu, Chengxuan, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
100

Student engagement for college students with the hidden disability of orthostatic intolerance /

Karabin, Beverly Lynn. January 2009 (has links)
Dissertation (Ph.D.)--University of Toledo, 2009. / Typescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements for The Doctor of Philosophy Degree in Higher Education." Bibliography: leaves 274-302.

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