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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.
51

Processo biotecnol?gico voltado a produ??o de estoques poliploides do camar?o-branco litopenaeus vannamei (decapoda, penaeidae)

Accioly, Ingrid Vilar 25 March 2013 (has links)
Made available in DSpace on 2014-12-17T14:05:22Z (GMT). No. of bitstreams: 1 IngridVA_TESE_Parcial.pdf: 1546645 bytes, checksum: 082397e35198d8c6624ddff83583508c (MD5) Previous issue date: 2013-03-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / without practical results so far. Protocols used in biotechnological cultured aquatic organisms aimed at increasing growth rates and disease resistance, have been studied and perfected. Among the available techniques, the application of chromosomal manipulation, although still nascent, is presented as a tool aimed at mitigating ecological and economical issues in shrimp farming. The polyploidization artificial method already employed in fish and shellfish, has been widely researched for use in farmed shrimp. Some limitations of this method of expansion in shrimp refer to a better knowledge of cytogenetic aspects, the level of sexual dimorphism and performance in growing conditions. To contribute on some of these issues, the present study aimed to characterize cytogenetic species Litopenaeus vannamei (Decapoda) and Artemia franciscana (Anostraca), analyze the effectiveness of methods for detection of ploidy, through the use of flow cytometry in processes of induction polyploidy cold thermal shock at different stages of development of newly fertilized eggs. Additionally, aimed also the qualitative and quantitative comparison of larval development between diploid and polyploid organisms, besides the identification of sexual dimorphism in L. vannamei, through geometric morphometrics. The results provide information relevant to the improvement and widespread use of biotechnological methods applied toward national productivity in shrimp farming / A melhoria gen?tica de planteis reprodutores, baseada no melhoramento cl?ssico tem sido tentada, mas sem resultados pr?ticos, at? o momento. Protocolos biotecnol?gicos utilizados em organismos aqu?ticos cultivados que visam aumentar as taxas de crescimento e resist?ncia a doen?as, v?m sendo estudados e aperfei?oados. Entre as t?cnicas dispon?veis, a aplica??o de manipula??o cromoss?mica, embora ainda incipiente, se apresenta como ferramenta voltada a mitigar quest?es ecol?gicas e econ?micas na carcinicultura. A poliploidiza??o artificial, m?todo j? empregado em peixes e moluscos, vem sendo largamente pesquisado para o uso em camar?es cultivados. Algumas limita??es da expans?o deste m?todo em camar?es se referem a um melhor conhecimento de aspectos citogen?ticos, do n?vel de dimorfismo sexual e performance em condi??es de cultivo. Visando contribuir sobre algumas destas quest?es, realizou-se ? caracteriza??o citogen?tica das esp?cies Litopenaeus vannamei (Decapoda) e Artemia franciscana (Anostraca), foi analisada tamb?m a efic?cia do uso da citometria de fluxo como m?todo de detec??o da ploidia em processos de indu??o artificial por choque t?rmico ? frio, em diferentes fases do desenvolvimento de ovos rec?m-fertilizados de Litopenaeus vannamei. Adicionalmente, visou-se, ainda, a compara??o qualitativa e quantitativa do desenvolvimento larval entre organismos diploides e poliploides, al?m da identifica??o do dimorfismo sexual em L. vannamei, por meio da morfometria geom?trica. Os resultados obtidos propiciam informa??es que contribuem para o aprimoramento e difus?o do uso aplicado de m?todos biotecnol?gicos voltados ao incremento da produtividade na carcinicultura nacional / 2020-01-01
52

Polissacar?deos sulfatados de interesse farmacol?gico no camar?o litopenaeus schimitti

Santos, Vanessa Olinto dos 12 June 2006 (has links)
Made available in DSpace on 2014-12-17T14:03:41Z (GMT). No. of bitstreams: 1 VanessaOS.pdf: 1126102 bytes, checksum: dba464c890585c6be32a3fd2dc600a81 (MD5) Previous issue date: 2006-06-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Sulfated Polysaccharides with unique chemical structures and important biological activities has been found in a diversity of sea invertebrates. For that, to exist a huger interest on the biotechnology field in the research theses sulfated compounds isolated from sea organisms. Despite the privileged brazilian position for these compounds attainment, there are still a few scientific informations about the isolated substances and their biological activities. A head the displayed, the present work has for objectives, to evaluate the pharmacological properties of the glycosaminoglycans isolated from the sea shrimp Litopenaeus schimitti on homeostasis, blood coagulation, leukocytes migration and platelet/leukocyte adhesion. For this, yhe glycosaminoglycans were extracted from crustacean tissues by proteolysis, fractionation with acetone and later submitted to pharmacological assays. The crustacean tissues showed compounds heparin-like, with anticoagulant activity of 45 IU/mg and 90 IU/mg, respectively. These molecules showed low residual hemorrhagic effects in the tested concentration (100 ?g/mL), when compared to unfractionated commercial heparin (UFH). Another dermatan sulfate-like compound, predominately constituted for disulfated disaccharides, was isolated from crustacean abdomen. This compound showed an efficient effect on leukocytes migration inhibition, in the concentration of 15 ?g/mL, reducing the cellular infiltration in 65% when compared to the controlled animals. In this same concentration, the DS reduced in 60% the protein concentration of the peritoneal exudates. In the concentration, this compound of 0.5 mg/mL, it was capable to reduce in 40% platelet/leukocytes adhesion. Our data demonstrate that these sulfated polysaccharides isolated from the shrimp L. schimitti will can be used as bioactive compounds, appearing as active principles for pharmacological development, anticoagulants and inflammatory response regulators / Polissacar?deos sulfatados com caracter?sticas estruturais distintas e importantes atividades biol?gicas t?m sido encontrados em uma diversidade de invertebrados marinhos. Por isso existe um grande interesse no campo da biotecnologia na pesquisa destes compostos sulfatados isolados de organismos aqu?ticos. No entanto, apesar da posi??o privilegiada do Brasil para a obten??o destes compostos, ainda s?o poucas as informa??es cient?ficas sobre as subst?ncias isoladas e suas atividades biol?gicas. Diante do exposto, este presente trabalho teve por objetivos avaliar os potenciais farmacol?gicos dos glicosaminoglicanos (GAGs) isolados do camar?o marinho Litopenaeus schimitti, sobre a hemostasia, coagula??o sang??nea, migra??o leucocit?ria e ades?o celular. Para isso os GAGs foram extra?dos dos tecidos do crust?ceo mediante prote?lise, fracionamento com acetona e posteriormente submetidos aos ensaios farmacol?gicos. Os tecidos do crust?ceo, abd?men e cefalot?rax, apresentaram compostos semelhantes ? heparina (heparin?ides) com atividade anticoagulante de 45 UI/mg e 90 UI/mg, respectivamente. Estas mol?culas apresentaram baixo efeito hemorr?gico residual na concentra??o de 100 ?g/mL, quando comparada com a heparina comercial n?o fracionada (HNF). Um outro composto semelhante ao dermatam sulfato (DS), constitu?do predominantemente por dissacar?deos dissulfatados foi isolado do abd?men do crust?ceo. Este composto apresentou, na concentra??o de 15 ?g/?L, uma inibi??o significativa (P<0.01) da migra??o leucocit?ria, reduzindo a infiltra??o celular em 65% quando comparado com os animais controle. Nessa mesma concentra??o o DS reduziu em 60% a concentra??o de prote?nas do lavado peritonial. As an?lises qualitativas da composi??o celular do exudato peritonial foram similares ao encontrado para os animais controles em todas as concentra??es testadas. Na concentra??o de 0,5 mg/mL foi capaz de reduzir em 40% a ades?o das plaquetas aos leuc?citos. Os dados obtidos demonstram que estes polissacar?deos sulfatados isolados do camar?o L.schimitti podem vir a ser utilizados como compostos bioativos, podendo surgir como princ?pios ativos para o desenvolvimento de f?rmacos, anticoagulantes e moduladores da resposta inflamat?ria
53

How Leaders Think: Measuring Cognitive Complexity in Leading Organizational Change

Vurdelja, Iva 01 July 2011 (has links)
No description available.

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