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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.
31

Indu??o de calos em anteras e poliploidia em gen?tipos de melancia

Silva, Carla Maria de Jesus 29 March 2018 (has links)
Submitted by Verena Pereira (verenagoncalves@uefs.br) on 2018-07-03T23:23:34Z No. of bitstreams: 1 TESE 2018 - Doutorado RGV_UEFS - Carla Maria de Jesus Silva.pdf: 1687907 bytes, checksum: 3e9fe14e189c00f951079ca2a71e3c66 (MD5) / Made available in DSpace on 2018-07-03T23:23:34Z (GMT). No. of bitstreams: 1 TESE 2018 - Doutorado RGV_UEFS - Carla Maria de Jesus Silva.pdf: 1687907 bytes, checksum: 3e9fe14e189c00f951079ca2a71e3c66 (MD5) Previous issue date: 2018-03-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The watermelon (Citrullus lanatus) is a very important vegetable for a region of Northeast Brazil due to its adaptation as the natural conditions and the good characteristics of the fruit that are obtained. The aims of the current study are to assess watermelon genotype responses to calluses in anthers by using growth and temperature regulators, and to induce polyploidy through colchicine use (at different concentrations), exposure time, mechanical scarification and application methods. Anthers of Smile and Sugar Baby lines were inoculated in MS medium at different concentrations of 2.4-D or of BAP with 2.4-D, in combination with the pre-treatment (low temperature). Crimson Sweet cultivar seedlings were treated with different colchicine concentrations at two different times, with and without scarification, in order to induce polyploidy. Line LDRO was subjected to different colchicine concentrations at two different times and application methods: a) direct in the seed method (with, and without, scarification) (DSM, WE and WOE), b) Radicle emission method (ERM), c) Hypocotyl and root insertion point method (HRIM), d) At the apex of the seedling method (ASM) and e) Inverted hypocotyl method (IHM). Crimson Sweet flower buds were subjected to colchicine, at two different times, in order to induce polyploidy. Results have shown that 2.4-D often induced callus formation in both lines, but BAP/2.4-D interaction and pre-treatment did not increase the induction frequency. Crimson Sweet showed higher induction rate at 0.2% colchicine for 48h, WE. Line LDRO presented plants with tetraploid cells at 0.2% colchicine for 24 and 48h. The method 0.2% DSM, WE and WOE also generated plants with tetraploid cells. The diameter of treated pollen grains in flower buds have increased; the higher rate of non-reduced gametes induction was 16.07% and flower bud diameter (1.5mm) was estimated as adequate for induction / A melancia (Citrullus lanatus) ? uma hortali?a muito importante para a regi?o Nordeste do Brasil por sua adapta??o as condi??es clim?ticas e pelas boas caracter?sticas de fruto que se obt?m. Os objetivos desse trabalho foram avaliar as respostas de gen?tipos de melancia quanto ? indu??o de calos em anteras utilizando reguladores de crescimento e temperatura; e induzir a poliploidia mediante o uso da colchicina em diferentes concentra??es, tempos de exposi??o, escarifica??o mec?nica e m?todos de aplica??o. Anteras das linhagens de Smile e Sugar Baby foram inoculadas em meio MS sob diferentes concentra??es de 2,4-D ou BAP com 2,4-D, associado ao pr?-tratamento (baixa temperatura). Para indu??o de poliploidia, sementes da cultivar Crimson Sweet foram tratadas com diferentes concentra??es de colchicina, em dois tempos, com e sem escarifica??o. Para a linhagem LDRO, utilizaram-se diferentes concentra??es de colchicina em dois tempos e m?todos de aplica??o: a) M?todo direto na semente (com escarifica??o e sem escarifica??o) (MDS, CE e SE), b) M?todo da semente com emiss?o da rad?cula (MER), c) M?todo no ponto de inser??o do hipoc?tilo e raiz (MIHR), d) M?todo no ?pice da pl?ntula (MAP) e e) M?todo do hipoc?tilo invertido (MHI). Na indu??o de poliploidia em bot?es florais de Crimson Sweet utilizou-se colchicina em dois tempos. Os resultados mostraram que o 2,4-D induziu a maior frequ?ncia de calos nas duas linhagens, a intera??o BAP com 2,4-D e o pr?-tratamento, n?o aumentaram a frequ?ncia de indu??o. Para Crimson Sweet, o maior percentual de indu??o foi obtido com colchicina a 0,2% por 48 h, SE. Para LDRO, observou-se uma frequ?ncia de plantas com c?lulas tetraploides com colchicina a 0,2% por 24 h e 48 h. Nos m?todos 0,2% MDS CE e MHI observou-se tamb?m plantas com c?lulas tetraploides. Em bot?es florais, o di?metro dos gr?os de p?len tratados aumentou; o maior percentual de indu??o de gametas n?o reduzidos foi de 16,07% e; o di?metro em torno de 1,5 mm do bot?o floral foi estimado como adequado para indu??o
32

Estudo de testes in vitro para predição de fertilidade de machos mamíferos / Study of in vitro assays to predict mammalian male fertility

Corcini, Carine Dahl 25 June 2010 (has links)
Made available in DSpace on 2014-08-20T13:32:55Z (GMT). No. of bitstreams: 1 tese_carine_dahl_corcini.pdf: 732454 bytes, checksum: 17c0395123a3b5438e40b167f5247599 (MD5) Previous issue date: 2010-06-25 / The knowledge of the reproductive potential of a male has economical and reproductive importance, especially if he is used in artificial insemination programs. The conventional assays for evaluating seminal quality do not have the capacity of measuring the fertilizing potential of a sample, they only indicate if it is within the acceptable parameters for insemination, according to the Brazilian College of Animal Reproduction. Into this context, the in vitro sperm penetration assay presents itself as an alternative laboratorial test to categorize fertile males regarding their fecundation capacity, since they mimic in vitro what happens in vivo. However, this assay has its use limited by the difficulty of execution and by the utilization of high cost equipment. The present work aimed to find a new biological model to study male reproductive aspects and to evaluate alternatives to simplify and to decrease costs of the assay execution: use of the chicken egg inner perivitelline layer (IPVL) penetration assay and its association with in vitro and in vivo parameters; use of BTS as incubation media for the in vitro penetration assay, and female gametes cryopreservation using different methods. It was concluded that: 1) Calomys laucha can be used as a biological model; 2) it is possible to use the inner perivitelline layer as a substrate in assays to predict fertility of Calomys laucha males; 3) the IPVL has receptors that allow swine sperm binding, therefore presents potential for use in male fertility diagnostic tests; 4) it is possible to use BTS as incubation media for the in vitro penetration assay, in oocytes or in IPVL, and in water-bath without CO2, and 5) the cryopreservation of ovaries at -20ºC or the refrigeration of oocytes in PBS at 5ºC before the execution of the in vitro oocyte penetration assay, using mTBM media, is an alternative to the use of fresh oocytes in tests to predict swine semen fertility. / O conhecimento do potencial reprodutivo de um macho é de importância econômica e reprodutiva, principalmente se ele é utilizado em programa de inseminação artificial. Os testes convencionais que avaliam a qualidade seminal não possuem a capacidade de medir o potencial fertilizante de uma amostra e, apenas indicam se a mesma se encontra dentro dos parâmetros aceitáveis para a inseminação segundo o Colégio Brasileiro de Reprodução Animal. O teste de penetração espermática in vitro, aparece neste contexto como um teste laboratorial alternativo para categorizar os machos férteis, quanto a sua capacidade de fecundação, pois mimetizam in vitro o que acontece in vivo. No entanto, este teste tem seu uso limitado por ser de difícil execução e por utilizar equipamentos de alto custo. O presente trabalho objetivou encontrar um novo modelo biológico para estudos sobre aspectos reprodutivos de machos e avaliar alternativas para simplificar e diminuir custos para execução do teste: utilização do teste de penetração na membrana perivitelina interna do ovo da galinha (IPVL) e sua associação com parâmetros in vitro e in vivo; utiilização do BTS como meio de incubação do teste de penetração in vitro e utilização de diferentes maneiras de criopreservação de gametas femininos. Foi concluído que: 1) Calomys laucha pode ser utilizado como modelo biológico; 2) é possível utilizar a membrana perivitelina interna como substrato de teste para predizer a fertilidade de machos Calomys laucha; 3) a IPVL possui receptores que permitiram a ligação do espermatozóide suíno, apresentando potencial para ser utilizada em diagnóstico de fertilidade de machos; 4) é viável utilizar BTS como meio para realização do teste de penetração in vitro em ovócito ou IPVL, em banho-maria sem a presença de CO2 e 5) o congelamento de ovários a -20ºC ou o acondicionamento a 5º C dos ovócitos em PBS para realizar o teste de penetração ovocitária in vitro, utilizando o meio mTBM, é uma alternativa para predizer a fertilidade de sêmen suíno.
33

Les figures de la maternité / Motherhood figures

Térel, Julie 09 December 2016 (has links)
Les évolutions sociétales - émancipation de la femme, maîtrise de la fécondité, acceptation del’homosexualité, multiplication des formes de conjugalité, nouveaux modèles familiaux, médicalisation de laprocréation - ont bouleversé le rapport entre maternité de fait et maternité juridique.La femme qui revendique le statut de mère n’est plus nécessairement celle qui a porté et mis au mondel’enfant. Les techniques d’assistance médicale à la procréation ont ouvert le champ des possibles enpermettant à la femme de réaliser son désir d’enfant, indépendamment des contraintes temporelles oubiologiques. Pourtant, la mère gestationnelle apparaît, aujourd’hui encore, comme la figure certaine de lamaternité. Elle a vu ses droits accrus par un mouvement d’harmonisation du droit de la filiation, jusqu’àdevenir l’égale de l’homme. Elle a cessé d’être identifiée par son statut conjugal, et est désormais définie parréférence au fait biologique maternel de l’accouchement. L’enfantement marque alors la singularité de lamaternité en tant que figure de rattachement, car elle est le seul vecteur d’identification spatio-temporelle del’enfant. Un ordre public fort en la matière est donc de rigueur : l’accouchement, qui détermine l’état civil del’enfant, ne devrait pas pouvoir être dissimulé. En revanche, la fonction maternelle de parenté devraitdavantage être soumise à la volonté de la femme qui se revendique mère. La mère gestationnelle, qui devraittoujours pouvoir établir un lien de filiation, devrait également pouvoir refuser l’établissement d’un tel lien,au profit d’une autre figure maternelle plus incertaine car reposant sur la volonté d’être mère, volontééventuellement corroborée par un lien génétique. Autrement dit, la filiation maternelle de l’enfant devraitpouvoir être transférée afin d’être en concordance avec la réalité sociologique.La multiplication des figures de la maternité conduit ainsi à une rénovation de la conception traditionnelle dela maternité, par un rééquilibrage du rôle joué par les éléments objectifs et subjectifs / A number of developments in society - the emancipation of women, birth control, the acceptanceof homosexuality, the diversification of couple arrangements, new family models, the increasingly medicalapproach to procreation - have shaken up the link between motherhood in fact and motherhood in law.The woman claiming the title of mother is no longer necessarily the one who bore the child and brought itinto the world. Assisted reproductive technology has opened up possibilities by allowing women who want achild to have one, regardless of restrictions related to time or biology. However, the “gestation mother”remains to this day the definite mother figure. Her rights have increased through the harmonisation of thelaws of filiation, eventually making her the man’s equal. She is no longer identified by her marital status andis now defined in relation to the biological process of giving birth. Giving birth hence highlights thespecificity of motherhood as an attachment figure, being the only means of identification in space and timefor the child. A strong public policy is therefore required in this area: giving birth should not be concealable,since it determines the child’s status in law. On the other hand, the maternal parenting role should dependmore on the will of the woman who claims the title of mother. The gestation mother, who should always beable to ascertain the filiation, should also be able to refuse such filiation, in favour of another mother figurenot as firmly ascertained, since her status is dependent on the will to be the mother, a will possiblycorroborated by filiation. The child’s maternal filiation should be transferrable in order to reflect the socialreality.The multiplication of mother figures has thus led to an overhaul of the traditional conception of motherhood,by rebalancing the role played by objective and subjective elements.
34

Repenser le droit de la reproduction au prisme du projet parental / Reconsidering the legal framework of reproduction through the lense of the "parental project"

Mesnil, Marie 11 December 2015 (has links)
À partir de la notion de projet parental, nous souhaitons déconstruire, en droit, l'assignation des femmes aux questions reproductives. En effet, le corpus juridique relatif à la reproduction participe à la perpétuation des stéréotypes de genre et en particulier, ceux liés à la division sexuée du travail. Le projet parental est une notion qui a émergé avec les techniques reproductives. Pour autant, l'analyse du cadre relatif aux techniques de PMA montre de quelle manière celui-ci renforce les stéréotypes de genre. Les conditions d'accès aux méthodes de PMA sont empreintes de naturalisme et une comparaison entre le droit français et le droit suisse montre le caractère construit de ces références constantes à la nature. L'établissement du lien de la filiation renforce le cadre naturaliste : d'un côté, la filiation est établie pour les projets parentaux réalisés dans le cadre légal selon les règles du droit commun et renforce la différenciation des fondements à la filiation selon le sexe du parent ; de l'autre, les projets parentaux qui s'écartent du cadre naturaliste sont relégués aux marges du droit de la filiation, même s'ils doivent aujourd'hui être reconnus sous la pression du législateur en matière de PMA et de la CEDH concernant la GPA. En dépit de l'état actuel du droit, la notion de projet parental pourrait promouvoir au sein du droit de la reproduction l'égalité entre les sexes et la liberté reproductive. En prenant appui sur le principe d'égalité entre les sexes et la liberté reproductive nous proposons de faire évoluer le droit de la reproduction, afin qu'il y ait davantage d'autonomie et d'égalité, tant en matière de filiation que d'accès aux actes médicaux non thérapeutiques en matière de reproduction que sont l'IVG, la contraception, la stérilisation et la PMA. Nous préconisons en particulier de modifier le droit commun de la filiation en y intégrant les techniques de PMA et en faisant de la volonté le fondement principal de l'établissement de la filiation. La promotion de l'autonomie reproductive lors de la mise en œuvre des droits reproductifs se traduit par un renforcement des droits des usagers du système de santé en matière de reproduction. À travers l'exemple du droit de la reproduction, nous montrons in fine de quelle manière le droit peut contribuer à favoriser au sein de la société l'autonomie des individus et l'égalité entre les sexes. / Starting from the concept of "parental project", we aim to deconstruct the traditional roles of women in reproductive matters from a legal standpoint. Gender stereotypes, especially those related to gendered division of labour, are indeed sustained by the current reproductive legal framework. The parental project is a concept introduced by law regulating the new reproductive technologies and yet, the analysis of legal aspects of medically assisted reproduction (MAR) stresses how gender stereotypes are in fact strengthened. The legal criteria to access MAR methods are defined based on Nature and comparing French and Swiss legal frameworks shows there are no fixed rules and thus, that references to Nature are not unbiased. Moreover, when it comes to rules of filiation, the naturalistic framework is further reinforced: on the one hand, when the parental project is carried out within the legal framework, filiation is established based on general law, corroborating the gendered legal basis of filiation; on the other hand, parental projects outside of the naturalistic framework are marginalized, and if nowadays filiation should also be recognized for children born in such conditions, it is only because of legal and jurisprudential developments. In spite of this, we think that the concept of "parental project" should promote, within the legal framework of reproduction, both gender equality and reproductive autonomy. Based on the principle of sex-equality and reproductive autonomy, our proposals aim to change dispositions regarding filiation and reproductive medical acts so that they could improve gender equality and reproductive autonomy. In particular, MAR should be addressed by the general law of filiation in order to make of will the main basis of parentage. Likewise, promoting autonomy in reproductive medical acts cannot proceed without rights of the health care users. Finally this research in reproductive law could be seen as a striking example of how law could foster gender equality and individual autonomy in society.

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