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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.
111

The anti-ulcer mechanisms of Cortex moutan against stress-induced gastric mucosal damage in rats /

Wong, Wing-hong. January 1998 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references.
112

Beiträge zur kenntnis der Peptischen und Tryptischen Verdauung des Eiweisses

Borkel, Curt, January 1903 (has links)
Thesis (doctoral)--Universität Leipzig, 1903. / Cover title. Includes references.
113

Estado nutricional, sintomas dispÃpticos e nÃveis de grelina em pacientes portadores de doenÃa de Crohn-correlaÃÃo com a atividade da doenÃa

Kamila Maria Oliveira Sales 15 March 2013 (has links)
nÃo hà / A perda de peso à uma queixa comum dos pacientes com doenÃa de Crohn, estando a desnutriÃÃo presente em 30-80% dos portadores dos casos. Foi demonstrado que pacientes com doenÃa de Crohn em inatividade apresentam sintomas dispÃpticos relacionados com alteraÃÃo no esvaziamento gÃstrico. No entanto, a correlaÃÃo da atividade da doenÃa com os parÃmetros antropomÃtricos, nutricionais e de saciedade ainda à objeto de investigaÃÃo. Portanto, o objetivo do nosso estudo foi correlacionar a atividade da doenÃa com o estado nutricional, sintomas dispÃpticos, esvaziamento gÃstrico, saciedade e nÃveis de grelina em pacientes com doenÃa de Crohn. Trata-se de um estudo transversal, analÃtico e quantitativo realizado em vinte pacientes com doenÃa de Crohn, classificados segundo um Ãndice de Atividade de DoenÃa de Crohn (Crohnâs Disease Activity Index â CDAI). Os pacientes foram submetidos a uma avaliaÃÃo nutricional, que se fundamentou na utilizaÃÃo de mÃtodos duplamente indiretos (Ãndice de massa corporal, dobra cutÃnea tricipital e circunferÃncia do braÃo). AlÃm disso, nos pacientes foi avaliado o consumo alimentar atravÃs de um recordatÃrio alimentar. Estes foram tambÃm submetidos a uma anÃlise do tempo de esvaziamento gÃstrico por teste respiratÃrio usando o 13C - Ãcido octanÃico ligado a uma refeiÃÃo sÃlida - e responderam a um questionÃrio validado (QuestionÃrio Porto Alegre de Sintomas DispÃpticos) para avaliar os sintomas dispÃpticos. Outro teste realizado foi o teste de saciedade(drinking test), no qual o paciente ingeriu 15 ml de uma bebida lÃquida padrÃo(Nutridrink), e era lhe perguntado o nÃvel de saciedade atravÃs de uma escala analÃgica. Durante o teste respiratÃrio, foram realizadas coletas de amostras de sangue para dosagem de grelina: basal( jejum) e pÃs-prandial. Os dados foram analisados estatisticamente pelos testes: t de Student, exato de Fisher, Mann-Whitney e correlaÃÃo de Spearman. Observou-se que os parÃmetros CDAI e IMC (p=0,0185) e CB (p=0,023) foram inversamente proporcionais, porÃm nÃo houve diferenÃa estatÃstica entre as correlaÃÃes do CDAI com prega cutÃnea tricipital( p=0,0543). Os pacientes nÃo apresentaram correlaÃÃo da atividade da doenÃa com o esvaziamento gÃstrico ( t Â- p=0,2533; t lag-p=0,3079). Entretanto, houve correlaÃÃo significativa do CDAI com todos os sintomas dispÃpticos (p=0,005). NÃo se verificou correlaÃÃo da atividade da doenÃa e o volume de lÃquido suportado. Entretanto, a atividade da doenÃa influenciou os nÃveis de grelina no pÃs-prandial (p=0,04). CONCLUSÃO: A atividade da doenÃa correlaciona-se com o estado nutricional, a presenÃa de sintomas dispÃpticos e nÃveis de grelina de pacientes portadores de doenÃa de Crohn. Entretanto nÃo existe correlaÃÃo com alteraÃÃes no esvaziamento gÃstrico e saciedade sugerindo que outros mecanismos possam estar envolvidos.
114

Efeito anti-ulcerogenico do extrato de Chlorella vulgaris / Antiulcerogenic effect of Chlorella vulgaris extract

Vinagre, Adriana Mendes 05 September 2005 (has links)
Orientadores: Edgard Ferro Collares, Alba Regina Monteiro Souza Brito / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T21:01:46Z (GMT). No. of bitstreams: 1 Vinagre_AdrianaMendes_M.pdf: 520546 bytes, checksum: 8639e020093258b50bba40d8d83f839c (MD5) Previous issue date: 2005 / Resumo: A úlcera péptica acomete cerca de 10% da população mundial; inseridos dentro dessa porcentagem estão milhares de brasileiros. Essa patologia é causada por um desbalanço entre os mecanismos protetores e agressores da mucosa, e é resultado da associação de diversos fatores agressores endógenos (ácido, pepsina e bile), fatores exógenos predisponentes às condições de vida (estresse, fumo, álcool, uso continuo de drogas antiflamatórias não esteróides, ingestão de determinados alimentos e a presença do Helicobacter pylori) e a predisposição genética. Atualmente, as terapêuticas utilizadas no tratamento das lesões são: antiácidos, anticolinérgicos, antagonistas de receptores H2 para histamina, inibidores da bomba de próton, antibióticos e mais raramente alguns procedimentos cirúrgicos. A aplicação de qualquer esquema terapêutico com emprego de uma ou mais destas drogas ou procedimento cirúrgico pode ocasionar alguns efeitos colaterais e não obrigatoriamente é eficaz. A utilização de plantas medicinais no tratamento de doenças vem se desenvolvendo na última década. Algumas plantas têm atividade antiulcerogênica. Há evidências que a alga Chlorella vulgaris pode modificar a resposta imune celular, tem atividade antitumoral, antimetastática e antiulcerogênica. O objetivo do presente estudo foi avaliar a atividade antiulcerogênica da alga Chlorella vulgaris em modelos agudos e um modelo crônico de indução de úlceras. Ratos Wistar foram utilizados para determinação do esvaziamento gástrico (EG) e modelos de úlcera induzida por etanol e ácido acético, enquanto camundongos swiss foram utilizados para os modelos de úlcera através de ligadura do piloro e piroxicam. Para avaliar o efeito sobre o esvaziamento gástrico (EG) do extrato de Chlorella vulgaris (ECV) foi utilizada uma refeição de prova (RP) liquida com extrato nas concentrações de 50mg/mL e 100mg/mL do ECV. Para o estudo dos modelos agudos de ligadura do piloro, etanol e piroxicam e do modelo crônico, foram utilizadas as doses de 250, 500 e 1000mg/kg de ECV para a prevenção e o tratamento das lesões. No modelo crônico também foi utilizada a fração acetato obtida do ECV na dose de 5mg/100g e foi dosada a quantidade de fator de crescimento epidermal (EGF) produzido na região da úlcera. O estudo da toxicidade do ECV foi realizado através da medida de ganho de peso dos ratos e peso dos órgãos como rins, pulmões, fígado e coração, visto que os primeiros sinais da toxicidade dada por um extrato é a perda de peso corporal e dos órgãos.O ECV, nas concentrações empregadas, não interferiu no EG quando preparado como uma RP liquida em comparação com o veículo (água). O extrato não alterou nenhum dos parâmetros bioquímicos como pH, quantidade de H+ e peso do suco gástrico, no modelo de ligadura do piloro. O ECV não preveniu a formação de úlceras no modelo de piroxican, mas evitou a formação de lesões causadas por etanol nas doses de 500 e 1000 mg/kg. Esse efeito desapareceu quando o etanol foi empregado duas horas após o pré-tratamento com ECV na dose de 1000 mg/kg. No modelo de úlcera crônica o ECV, nas doses de 500 e 1000 mg/kg, foi capaz de diminuir significativamente as lesões causadas pelo ácido acético, não alterando no entanto, a quantidade de EGF produzida na zona de cicatrização, quando comparados ao controle água. Além disso, o tratamento prolongado com o ECV na dose de 500 mg/kg alterou significativamente a evolução do ganho de peso desses animais. Em conclusão, o ECV, como complemento alimentar, pode ser uma alternativa no tratamento da úlcera péptica gástrica / Abstract: About 10%of the world¿s population suffer from peptic ulcer, within this percentage we find thousands of Brazilians. This pathology is caused by an unbalance between the protection and attack mechanisms of the stomach lining, and is the result of the association of various endogenous attack factors (pepsin, acid, bile), exogenous factors pertaining to life style (stress, smoking, alcohol intake, continuous use of non-steroidal anti-inflammatory drugs, ingestion of certain types of food and the presence of Helicobacter Pylori) and genetic predisposition. Nowadays, the therapeutic methods used for the treatment of the lesions are: Anti-acids, anti-cholinergic, antagonist H2 receptors for histamine, proton bombs; certain surgical procedures are also applied, though much less frequently. Any therapeutic method that involves the use of one or more of the drugs and/or procedures above mentioned may cause some side effects and is not necessarily effective. The use of medicinal plants in the treatment of diseases has been developing over the past decade. Some plants have an anti-ulcer activity. There is evidence that the Chlorella vulgaris algae may modify cellular immune response, and there is also evidence to its anti-tumor, anti-metastasis, anti-ulcer activity. The objective of this present study was to evaluate the anti-ulcer activity of the Chlorella vulgaris algae acute models of ulcer induction and also in one chronic model of ulcer induction. Wistar rats were used to determine gastric emptying (GE) and in models of ulcer induced by ethanol and acetic acid, while swiss mice were used for the piloro ligature and piroxicam ulcer induction models. In order to evaluate the effect of the Chlorella vulgaris extract (ECV) on gastric emptying (GE) a liquid proof meal (PM) with the extract in the concentration of 50mg/l and 100mg/l was usedIn the study of the acute piloro ligature, ethanol and piroxicam models, and in the chronic model, dosages of 250, 500 and 1000mg/kg of ECV were used in the prevention and treatment of the lesions. In the chronic model the fraction of acetate obtained from the ECV in the dosage of 5mg/100g was also used, and the amount of epidermal growth factor (EGF) produced in the region of the ulcer was measured. The toxicity study of the ECV was done by measuring the weight gain of the rats and the weight of their organs i.e. kidneys, lungs, liver, and heart, once the first signs of toxicity by an extract are loss of body and organ weight. The ECV, in the concentration used, did not interfere with the GE when prepared as a liquid PM in comparison to the vehicle (water). The extract did not alter any of the biochemical parameters such as pH, amount of H+ and weight of the gastric juice in the piloro ligature model. The ECV did not prevent the formation of ulcer in the piroxicam model, but it prevented the formation of lesions caused by ethanol in the dosage of 500 and 1000mg/kg. This effect disappeared when ethanol was ministered two hours after the pre-treatment with ECV in the dosage of 1000mg/kg. The chronic ulcer induction model the ECV, in the dosage of 500 and 1000mg/kg, was able to significantly lessen the lesions caused by acetic acid, not altering, however, the amount of EGF produced in the scar tissue area when compared to the water control. Furthermore, the long-term treatment with ECV in the dosage of 500mg/kg significantly altered the evolution of weight gain of these animals. In conclusion, the ECV, as a dietary complement, may be an alternative in the treatment of gastric peptic ulcer / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
115

Atividade gastroprotetora do hidroxicitronelal em modelos de lesÃo gÃstrica aguda em camundongos. / Gastroprotective activity of hidroxicitronelal in models of acute gastric injury in mice.

CÃsar Braga de Holanda OsÃrio 30 September 2011 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O hidroxicitronelal à um composto amplamente usado como fragrÃncia em cosmÃticos. Este composto pode ser obtido a partir da semi-sÃntese do citronelal, um terpeno isolado do Ãleo essencial de citronela (Cymbopogon marginatus) ou de cidreira (Melissa officinalis), e tambÃm vÃrias outras plantas. O objetivo deste estudo à demonstrar a atividade gastroprotetora do hidroxicitronelal em modelos de lesÃo gÃstrica aguda. A manipulaÃÃo dos animais e os protocolos experimentais foram registrados no Comità de Ãtica Institucional (CEPA) sob o nÃmero 052/2011. Foram utilizados camundongos swiss, que foram divididos em grupos de 8 (n = 8), e foram submetidos a um perÃodo de jejum de 16h, entÃo foram tratados com HC nas doses de 0.5; 2.5 e 12,5 mg/Kg ou NAC (750 mg/Kg). ApÃs 30 minutos os animais receberam 0,2 ml de etanol absoluto v.o. E apÃs 30 min, os animais foram sacrificados, os estÃmagos removidos e analisados para determinaÃÃo do Ãndice de lesÃo ou feito homogenatos para a dosagem de GSH (glutationa reduzida). A fim de se investigar o envolvimento das prostaglandinas, NO e dos canais de potÃssio, antes do tratamento com HC os animais receberam L-NAME(20mg/Kg) e/ou L-arginina(600mg/Kg), indometacina (10mg/Kg) e/ou misoprostol(0.03Âg/Kg), Glibenclamida(5mg/Kg) e/ou DiazÃxido(3mg/Kg). Para investigar a participaÃÃo dos receptores TRPV1 , os animais receberam capsaicina(0,3mg/Kg) e/ou capsazepina(5mg/Kg). No modelo de Ãlcera gÃstrica induzida por AINEs, os animais foram tratados com HC (12.5; 50 e 200 mg/Kg) ou Cimetidina (100 mg/Kg) 30 min antes do tratamento com indometacina (60 mg/Kg), e depois de 6h os animais foram sacrificados, os estÃmagos removidos e analisados sob o critÃrio de escores de lesÃo. No modelo de lesÃo por etanol, HC nas doses de 0,5; 2.5 e 12 mg/Kg foi capaz de inibir a lesÃo em 31; 53 e 69% respectivamente. HC tambÃm recuperou os nÃveis de GSH na mucosa em 31.19% quando comparados com o grupo lesÃo. L-NAME, Glibenclamida e Indometacina foram capazes de reverter o efeito de HC, demonstrando o envolvimento das Prostaglandinas, NO e dos canais de potÃssio, em seu mecanismo de aÃÃo. Capsazepina foi inefetiva em reverter o efeito de HC, assim excluindo o possÃvel envolvimento dos receptores TRPV1. No modelo de lesÃo por AINEs, HC nas doses testadas reduziu os escores de lesÃo em 28.8, 56.3, e 84.1% respectivamente. Podemos concluir que HC possui uma atividade farmacolÃgica gastroprotetora sobre a mucosa do estÃmago. Essa proteÃÃo parece ser mediada em parte pela modulaÃÃo de Prostaglandina/NO/ KATP, que à de papel fundamental na manutenÃÃo do fluxo sanguÃneo e na defesa da mucosa gÃstrica. / The hydroxycitronellal is a compound widely used as fragrance in cosmetics. This compound can be obtained by semi-synthesis from citronellal, a terpenoid isolated from essential oil of citronella (Cymbopogon marginatus) or Balm (Melissa officinalis), and also found in other plants. The aim of this study is to demonstrate the gastroprotective of hydroxycitronellal in gastric ulcer models. Animal handling and experimental protocols were registered on the Institutional Ethics Committee (CEPA) under number 052/2011. Swiss mice were used, were divided into groups of 8 (n = 8), and undergo fasting of 16h, then were treated with HC in doses 0.5; 2.5 and 12,5 mg/Kg or NAC (750 mg/Kg). After 30 min they received 0, 2 ml of absolute ethanol per oral and after 30 min, the animals were sacrificed and stomachs removed and analyzed the lesion index and dosage of GSH (reduced glutathione). In order to investigate the involvement of prostaglandins, NO and potassium channels, before treatment with HC animals received L-NAME (20mg/Kg) or L-arginine (600mg/Kg), indomethacin (10mg/Kg) or misoprostol (0.03Âg/Kg), Glibenclamide (5mg/Kg) or Diazoxide (3mg/Kg). To investigate the participation of TRPV1 receptors, animals received capsaicin (0,3mg/Kg) or capsazepina (5mg/Kg). In the model of injury by NSAIDâs, the animals were treated with HC (12.5; 50 and 200 mg/Kg) or Cimetidine (100 mg/Kg) 30 min before treatment with indomethacin (60 mg/Kg), and after 6h animals were sacrificed and stomachs removed and examined under-rated scores. In model of injury by ethanol, HC at the doses 0,5; 2.5 and 12 mg/Kg was able to prevent injury in 31.0; 52.9 and 69.3% respectively. HC also restored the GSH levels in mucosa in 31.19% compared to the ethanol group. LNAME, Glibenclamide and Indometacin were able to reverse the protective effect of HC, demonstrating the involvement of Prostaglandins, NO and potassium channels in its mechanism of action. Capsazepine was unable to reverse the effect of HC, thus excluding a possible involvement of TRPV1 receptors. In the model of injury by NSAIDâs, HC in tested doses reduces the injury scores in 28.8, 56.3, and 84.1%respectively. We can conclude that the HC has pharmacological activity with gastroprotetor effect in the gastric mucosa. This protection appears to be mediated in part by modulation of Prostaglandin/NO/KATP, which is of great importance in mucosal defense and in maintaining blood flow to the stomach.
116

Early gastric cancer detection in high-risk patients: a multicentre randomised controlled trial on the effect of second-generation narrow band imaging / 胃癌高リスク群を対象とした早期胃癌の発見における第二世代狭帯域光観察の効果についての多施設ランダム化比較試験

Yoshida, Naohiro 25 January 2021 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13388号 / 論医博第2220号 / 新制||医||1048(附属図書館) / (主査)教授 羽賀 博典, 教授 佐藤 俊哉, 教授 妹尾 浩 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
117

Patienters upplevelse av hälsa efter en gastric bypass operation : En litteraturstudie

Lundqvist, Elin, Stigenberg, Molly January 2021 (has links)
Bakgrund: Gastric bypass (GBP) är en viktminskningsoperation för patienter med ett BMI (Body Mass Index) >35. Operationen är en del av en viktminskningsprocess. Patienten bör själv ta ansvar i form av egenvård för att underhålla det nya levnadssättet för att främja hälsa. Syfte: Syftet med litteraturstudien är att sammanställa vetenskapligt underlag och beskriva patienters upplevelse av hälsa efter en gastric bypass operation. Metod: En deskriptiv design har använts i denna litteraturstudie som har baserats på totalt 10 vetenskapliga artiklar med inkludering av kvalitativ och kvantitativ ansats. Huvudresultat: Operationen hade bidragit till förändrade fysiska, psykiska och sociala upplevelser relaterat till hälsa. En tydlig reducering av vikten kunde utläsas och följdsjukdomar relaterat till fetma hade förbättrats. GBP operationen har bidragit till ökad livskvalitet, minskad social hämning och ökat intresse att delta i aktiviteter. Oönskade följder har rapporterats i form av överskottshud, gastrointestinala problem och osäkerhet. Slutsats: En GBP operation har visat sig vara en effektiv metod för patienters viktnedgång. Förändringar av det fysiska, psykiska och sociala upplevelser relaterat till hälsan har skett. Både positiva upplevelser och oönskade följder kan utläsas av resultatet från en GBP operation. Djupgående information och kunskap till patienter kan främja egenvård och bidra till återhämtning och följsamhet i det nya levnadssättet. / Background: Gastric bypass (GBP) is a weight loss surgery for patients with a BMI (Body Mass Index) >35. The surgery is part of the weight loss process. The patient should take responsibility in the form of self-care to maintain the lifestyle change to promote health. Aim: The aim of the literature study is to compile a scientific basis and describe the health experience of patients after a gastric bypass surgery. Method: In this literature study, a descriptive design has been used that has been based on a total of 10 scientific articles with the inclusion of a qualitative and quantitative approach. Main results: The operation had contributed to change of physical, mental and social experiences related to health. A clear weight reduction was observed and obesity comorbidity improved. The GBP surgery has contributed to improv the quality of life, reduced social inhibition and increased interest in participating in activities. Undesirable consequences in the form of excess skin, gastrointestinal problems and uncertainty have been reported. Conclusion: A GBP surgery has proven to be an effective method of weight loss for patients. There have been changes in the physical, mental and social experiences related to health. Both positive experiences and undesirable consequences can be deduced from the results of a GBP surgery. In-depth information and knowledge for patients can promote self-care and contribute to recovery and compliance in the new lifestyle.
118

Helicobacter Pylori Infection and Oncogene Expressions in Gastric Carcinoma and Its Precursor Lesions

Wang, Jie, Chi, David S., Kalin, George B., Sosinski, Christina, Miller, Lou Ellen, Burja, Izabela, Thomas, Eapen 29 January 2002 (has links)
Although it is fairly well accepted that Helicobacter pylori infection plays a significant role in causing gastric cancer, the exact mechanisms involved in its pathogenesis are unclear. We have examined the relationship between H. pylori infection and oncogene expression in different stages of disease progression from precursor lesions to gastric carcinoma. We used Diff-Quik stain to diagnose H. pylori infection and immunohistochemical stains against c-erbB-2, p53, ras, c-myc, and bcl-2 to determine expression of oncogenes. H. pylori infection was found in all cases of chronic gastritis, atrophic gastritis, intestinal metaplasia, and early gastric carcinoma, and in 16 of 30 (53%) cases of advanced gastric carcinoma. Overexpression of c-erbB-2 was found in 2 (7%) cases of advanced gastric carcinoma, which were H. pylori negative. Suppressor gene, p53, was overexpressed in 3 (30%) cases of intestinal metaplasia, 2 (33%) cases of early gastric carcinoma, and 18 (60%) cases of advanced gastric carcinoma. Of these 18 p53-positive advanced gastric cancer cases, 11 (61%) were H. pylori positive. Expression of ras p21 was found in 4 (40%) cases of H. pylori-negative normal mucosa, 10 (100%) cases of chronic gastritis, 1 (10%) case of atrophic mucosa, 6 (60%) cases of intestinal metaplasia, 2 (33%) cases of nonneoplastic mucosa adjacent to early gastric carcinoma, and 7 (23%) nonneoplastic mucosa adjacent to advanced gastric carcinoma, all of which showed H. pylori. No evidence of expression of either c-myc or bcl-2 was detected in any of the above-mentioned samples. The data suggest that H. pylori infection may increase expression of ras p21 proteins and induce p53 suppressor gene mutation early in the process of gastric carcinogenesis.
119

Regulation of duodenal mucosal bicarbonate secretion

Odes, Harold Selwyn 22 August 2017 (has links)
The present research studied the regulation of duodenal bicarbonate secretion in the anaesthetized guinea-pig, using a model that permitted the study of active transport of bicarbonate. It was determined that dibutyryl 3' ,5'-cyclic adenosine monophosphate, vasoactive intestinal polypeptide, prostaglandin E2, carbachol and theophylline are the chief agonists of duodenal bicarbonate secretion. Vasoactive intestinal polypeptide and prostaglandin E2 act directly via distinct receptors on the duodenal enterocytes, activating adenylate cyclase and protein kinase A in sequence to initiate bicarbonate secretion. In addition, there is good evidence that the inositol phospholipid and protein kinase C cascade is also involved, possibly to a lesser extent, since tetradecanoyl-phorbolacetate and prostaglandin F2a were agonists of bicarbonate secretion. Carbachol, using a m-cholinoceptor pathway, stimulates duodenal bicarbonate secretion by releasing vasoactive intestinal polypeptide. Consistent with this finding is the observation that carbachol has no receptors on duodenal enterocytes. The role of the nicotinic pathway in bicarbonate secretion, however, remains uncertain. Duodenal bicarbonate secretion can be inhibited by somatostatin and acetazolamide. Somatostatin selectively suppresses carbachol-stimulated and VIP-stimulated duodenal bicarbonate secretion, but not PGE2-stimulated bicarbonate secretion. Receptors for somatostatin coupled to adenylate cyclase could not be detected on isolated duodenal enterocytes, which strengthens the hypothesis that carbachol does not act directly on these epithelial cells, but via a second transmitter, vasoactive intestinal polypeptide. Carbonic anhydrase activity is necessary for secretion of bicarbonate, since acetazolamide-inhibition of this enzyme decreased bicarbonate secretion, both basal and stimulated by many different agonists. Carbonic anhydrase serves as a common final step in the generation of bicarbonate in duodenal enterocytes. This enzyme was located in the cytoplasm of cells in the villus as well as the crypt cells, implying that bicarbonate secretion occurs along the length of the villus and crypt. In summary, the present research has shown direct stimulation of duodenal bicarbonate secretion by vasoactive intestinal polypeptide, which participates also in themcholinergic pathway, and by prostaglandin E2. Adenylate cyclase and protein kinase A appear to be the intracellular messengers with the primary function of initiating duodenal bicarbonate secretion. However, there is convincing evidence that the inositol phospholipid and protein kinase C cascade also activates this secretion. Somatostatin selectively stops duodenal bicarbonate secretion. Carbonic anhydrase activity in the crypt and villus is required as the final common step in bicarbonate production.
120

Routine Evaluation with Gastric Ultrasound to Reduce Gastric Aspiration (REGURGA)

Jackson, Joel January 2024 (has links)
No description available.

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