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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.
211

Stem cell factor and c-kit in the ovine ovary

Gentry, Paula C. January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves [109]-132. Also available on the Internet.
212

The role of the Nodal-ALK7 signaling pathway in human ovarian cancer cells /

Xu, Guoxiong. January 2007 (has links)
Thesis (Ph.D.)--York University, 2007. Graduate Programme in Biology. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR32076
213

Single nucleotide polymorphism in the coding sequence of follicle stimulating hormone receptor and susceptibility to ovarian and endometrial cancer

Yang, Chongqing. January 2004 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
214

Dinâmica da vitelogênese durante a maturação ovariana em Artemesia longinaris

Silva, Rafaela Nunes da [UNESP] 28 February 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-28Bitstream added on 2015-03-03T12:06:48Z : No. of bitstreams: 1 000805066_20150708.pdf: 84839 bytes, checksum: a2201d3a364ce6fbdad0c2a63c6d8ee1 (MD5) / Sabe-se que em camarões peneídeos, a vitelogenina é sintetizada no ovário e hepatopâncreas, mas a contribuição relativa desses dois tecidos na síntese de vitelogenina ainda é incerta. Este processo pode diferir ainda de acordo com a espécie e estágio vitelogênico ou muda. Assim o presente estudo analisou a localização da produção de vitelogenina através de técnicas imunohistoquímicas, bem como, a quantificação do seu mRNA através do Real Time PCR em fêmeas de Artemesia longinaris em diferentes estágios de maturação ovariana (rudimentar - RU, em maturação - EM e maduro - MA). A espécie de camarão estudada apresenta altíssimo valor econômico. Assim, o estudo dos mecanismos da reprodução podem gerar dados para futuros projetos de produção em escala comercial, contribuindo com a preservação dos estoques naturais. A partir de análises moleculares confirmou-se a síntese de vitelogenina no ovário e hepatopâncreas de fêmeas de A. longinaris durante a maturação ovariana. Os níveis de expressão relativa de transcritos de vitelogenina no ovário e no hepatopâncreas durante a maturação ovariana demonstram que a dinâmica da síntese de vitelogenina é inversamente proporcional. A imunohistoquímica localizou a síntese endógena de vitelogenina nas células foliculares, nos oócitos pré-vitelogênicos e oócitos em vitelogênese inicial. E a síntese exógena de vitelogenina foi localizada nas células R dos túbulos hepatopancreáticos. Ainda, visto a grande contribuição do hepatopâncreas ao ciclo reprodutivo e às demais funções fisiológicas do animal, analisou-se o perfil celular do túbulo hepatopancreático nos estágios de maturação ovariana. Este órgão apresenta comportamento celular que se adapta ao ciclo reprodutivo em fêmeas, ou seja, o ciclo celular do hepatopâncreas além de obedecer a um ciclo digestivo é adaptado ao ciclo reprodutivo / It is known that in penaeid shrimp the vitellogenin is synthesized into the ovary and hepatopancreas, but the relative contribution of these two tissues in the synthesis of vitellogenin remains uncertain. This process differs according to the species and vitellogenesis stage or molt. Thus the present study examined the location of vitellogenin production by immunohistochemical techniques, as well as the quantification of its mRNA by Real Time PCR in female Artemesia longinaris at different stages of ovarian maturation (immature - RU, maturing EM and mature - MA). The shrimp species investigated presented a very high economic value. The study of the mechanisms of reproduction can generate data for future projects of commercial scale production contributing with the preservation of wild stocks. The molecular analyzes have confirmed the vitellogenin synthesis in the ovary and hepatopancreas of A. longinaris females during ovarian maturation. the relative expression level of vitellogenin transcripts in the ovary and the hepatopancreas during ovarian maturation show that the dynamics of vitellogenin synthesis is inversely proportional. By immunohistochemistry, it was located the endogenous synthesis of vitellogenin in follicular cells, in pre-vitellogenic oocytes and oocytes in early vitellogenesis. And the synthesis exogenous of vitellogenin was localized in cells R of hepatopancreaticos tubules. Also, given the great contribution of hepatopancreas reproductive cycle and other physiological functions of the animal, we analyzed the cellular profile of the hepatopancreatic tubule at stages of ovarian maturation. This organ has a cellular behavior that adapts to the reproductive cycle in females, in other words, the cellular cycle of hepatopancreas beyond to follow a digestive cycle is adapted to the reproductive cycle
215

Desenvolvimento morfológico dos ovários em embriões e fetos bovinos da raça Nelore

Diniz, Elmo Gomes [UNESP] 28 November 2001 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-11-28Bitstream added on 2014-06-13T19:23:41Z : No. of bitstreams: 1 diniz_eg_dr_jabo.pdf: 1766438 bytes, checksum: b28fd4b1e87d5ab565efa2f5084bd69a (MD5) / Pouco se sabe sobre os eventos morfológicos que ocorrem durante o desenvolvimento pré-natal das gônadas nas raças zebuinas. O objetivo deste estudo foi descrever os eventos morfológicos relacionados ao desenvolvimento pré-natal da gônada, incluindo a sua formação, identificação de células germinativas primordiais, surgimento de oogônios, oócitos e folículos em embriões e fetos da raça Nelore. Oitenta e um embriões e fetos bovinos, com idade variando de 26 a 240 dias após fecundação, foram coletados em frigoríficos. A idade dos fetos foi estimada a partir de medidas tomadas no sentido crânio-caudal e aplicadas à fórmula proposta por Rexroad et. al. (1974). O sexo foi identificado a partir de observações macroscópicas e usando a técnica do PCR (Polymerase Chain Reaction) somente quando as diferenças sexuais morfológicas não foram evidentes. Para histologia, as gônadas foram fixadas em líquido de Bouin por 24 horas. Após processamento histológico, cortes de tecido de 5mm, foram corados com hematoxilina-eosina. Os resultados mostraram que a crista gonádica se formou a partir de 29 dias após fecundação. No 34º dia, células germinativas primordiais foram identificadas. As oogônias surgiram em grande quantidade entre 50 e 100 dias e seu número reduziu drasticamente, atingindo números finais aos 140 dias. Os folículos primordiais, folículos em crescimento e antrais apareceram em média aos 95, 140 e 180 dias, respectivamente. Oogônias e folículos primordiais, de forma diferente dos folículos em crescimento, apresentaram diferenças significativas no seu diâmetro nos vários períodos estudados. Folículos antrais mostraram diâmetro médio de 96,92 l 31,07mm aos 180 dias , chegando atingir médias de1331,43 l 567,43mm aos 240 dias... / Little is known about morphological events occurring during the prenatal development of gonads in the Zebu breeds. The objective of this study was to describe the morphologic events related to the prenatal development of the gonad, including its formation, identification of primordial germinative cells, appearance of oogonia, oocytes and follicles in Nelore breed embryos and fetuses. Eighty-one bovine embryos and fetuses, with age range from 26 to 240 days following fecundation, were gathered in a local slaughter-house. The age of fetuses was estimated from measures taken in the cranium-caudal direction and applied to the formula proposed by Rexroad et. al. (1974). The sex was identified from macroscopic observations and using PCR (Polymerase Chain Reaction) technique only when the morphologic sexual differences were not evident. For histology, gonads were fixed into Bouin fluid for 24 hours. Then, 5mm-tissue cuts were stained with hematoxylin-eosin. The results showed that the gonadal ridge was developed from 29 days following fecundation. At the 34th day, primordial germ cells were identified. Oogonia arose in great quantity between 50 and 100 days and its number reduced dramatically, attaining final numbers at 140 days. The primordial follicles, growing follicles and antral follicles appeared on the average at 95, 140 and 180 days, respectively. Oogonia and primordial follicles, in a different way from growing follicles, presented significant differences in its diameter in the several periods studied. Antral follicles showed 96.92 l 31.07mm in diameter at 180 days, achieving means of 1331.43 l 567.43 mm at 240 days. The statistical analysis showed a positive and highly significant correlation (P< 0.01), between the oogonia diameter and its nucleus, as well as between the primordial and growing follicles with its oocytes and respective nuclei... (Complete abstract, access undermentioned eletronic address)
216

Métodos alternativos de muda forçada para poedeiras comerciais

Scherer, Miriani Rosa [UNESP] 15 August 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-15Bitstream added on 2014-06-13T20:37:15Z : No. of bitstreams: 1 scherer_mr_me_botfmvz.pdf: 181041 bytes, checksum: 323fdced019a1fe2524b9da8665d9db0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi avaliar métodos alternativos de muda forçada e compará-los ao método convencional (jejum) e ao grupo controle. Para isso realizou-se o experimento nas instalações do Setor de Avicultura da Faculdade de Medicina Veterinária e Zootecnia UNESP Botucatu SP. Foram utilizadas 480 aves da linhagem Isa Brown, com 80 semanas de idade, distribuídas em 6 tratamentos contendo 10 repetições de 8 aves por gaiola. O período experimental compreendeu período de descanso forçado com duração de 28 dias onde se avaliou os parâmetros de peso corporal, ovário, oviduto, fígado, gordura abdominal, teores de cálcio e fósforo contido na cinza do metatarso e desempenho produtivo das aves. Os tratamentos utilizados foram dietas de produção com restrição de componentes: T1 cálcio e fósforo, T2 cálcio, fósforo e sódio, T3 cálcio, fósforo, sódio e aminoácidos (metionina e lisina), T4 fornecimento de milho moído, T5 muda convencional através de jejum de 14 dias seguido de ração de produção até 28 dias e T6 grupo controle que recebeu ração de produção. Durante a muda todos os tratamentos receberam água e retirou-se o programa de luz artificial. O T5 promoveu maior perda de peso corporal que os demais tratamentos. Tais perdas repercutiram em incremento no consumo voluntário de ração de produção nas primeiras semanas após o período de jejum. O jejum permitiu uma completa regressão do trato reprodutivo das aves, que cessaram a postura no período. Os tratamentos com restrição de nutrientes e de milho, promoveram redução do peso vivo, do aparelho reprodutivo e do consumo voluntário de ração, porém não cessaram a produção de ovos. / The objective of this study was to evaluate alternative forced molting systems and compare then to the traditional system (fasting) and to the control group. The trial was carried out at the Faculdade de Veterinária e Zootecnia (UNESP-Botucatu) Poultry Section. Four hundred and lighty 488 Isa Brown line hens, 80 weeks old, were assigned to 6 treatments with 10 replicates of 8 hens per cage. The experiment comprised, a 28 day resting period during which, we evaluated live weight, ovary, oviduct, liver, abdominal fat, calcium and phosphorus in tarsus ash and production traits. Treatments were production diets with nutrient or ingredient restriction: T1 calcium and phosphorus, T2 calcium, phosphorus and sodium, T3 - calcium, phosphorus, sodium and aminoacids (lysine and methionine), T4 ground corn feeding, T5 conventional forced molting: 14 days fasting followed by production ration feeding until 28 days, T6 control group fed production ration. During the molting period all hens had access to water and the light program was suspended. TheT5 promoted larger bady weight loss than the other treatments. Such losses resulted in an increment in the voluntary intake in the first weeks after the fasting period. Fasting allowed a complete regression of the reproductive tract of the birds and interrupted laying. The ingredient restriction treatments and ground corn feeding promoted reduction of body weight, of the reproductive tract and of the voluntary feed intake. They reduced, bit they didn't interrupt the egg laying.
217

Histomorfometria ovariana de felinos domésticos (Felis catus) em distintas faixas etárias

Carvalho, Isadora Resende de [UNESP] 27 June 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-06-27Bitstream added on 2014-06-13T19:59:05Z : No. of bitstreams: 1 carvalho_ir_me_jabo.pdf: 937162 bytes, checksum: b3222df6a75dec2ba70752862072c779 (MD5) / O objetivo desse estudo foi avaliar a histologia e morfometria de ovários de 17 gatas classificadas de acordo com as idades G1 (4-12 meses); G2 (1-6 anos) e G3 (> 6 anos). Após realização da ovariosalpingo-histerectomia os ovários foram fixados, processados rotineiramente para a inclusão em parafina e corados com Hematoxilina-eosina. Os parâmetros morfométricos analisados foram: diâmetro (μm), área (μm2) e perímetro (μm) dos folículos e respectivos oócitos de diferentes tipos de folículos. A relação entre o crescimento do folículo e do oócito foi analisada. Os procedimentos estatísticos utilizados foram ANOVA, sendo as médias comparadas pelo teste de Tukey e as medianas pelo teste de Kruskal-Wallis, seguido do teste de comparações múltiplas de Dunn (P< 0,05). Ao todo foram 1039 folículos analisados histologicamente e houve diferença significativa nos diâmetros, áreas e perímetros foliculares e oocitários de folículos primordiais e primários unilaminares. Observou-se padrão bifásico para o crescimento do folículo e do oócito. Conclui-se que as gatas jovens obtiveram maiores valores em folículos primários unilaminares em relação às idosas. Sugere-se que o “pool” de folículos pequenos remanescentes e seus respectivos oócitos diminuem com a idade e que na fase senil esses folículos são de baixa qualidade, quando comparados ao início da vida reprodutiva. Estudos com morfometria do ovário poderão auxiliar pesquisas de tecnologias reprodutivas assistidas, como por exemplo, a maturação in vitro (MIV), já que o tamanho e a qualidade dos folículos e oócitos podem afetar a MIV em felinos domésticos. Adicionalmente, esses estudos poderão auxiliar na preservação de felinos selvagens em extinção / The aim of this study was to evaluate the histology and morphometry of ovaries of 17 cats classified according to ages G1 (4-12 months), G2 (1-6 years) and G3 (>6 years). After ovariosalpingohysterectomy the ovaries were fixed in paraformaldehyde 5% prior to embedding in paraffin and staining with haematoxylin-eosin. The morphometric parameters analyzed were: diameter (μm), area (μm2) and perimeter (μm) of follicles and oocytes from different follicles types. The relationship between the growth of the follicle and oocyte was analyzed. The statistical analysis were ANOVA and the means were compared by Tukey test and medians using the Kruskal-Wallis test followed by Dunn's multiple comparisons (P<0.05). A total of 1039 follicles were analyzed histologically and there were significant difference in follicular and oocyte diameter, area and perimeter of primordial and primary unilaminar follicles. It was observed a biphasic pattern for the growth of the follicle and oocyte. In conclusion, young queens had higher values in primary unilaminar follicles than older queens. It is suggested that the remaining pool of small follicles and their oocytes decreases with age and that follicles of older queens has low quality compared to the beginning of reproductive life. Ovarian morphology studies may assist in assisted reproductive technologies such as in vitro maturation (MIV), since it is known that the size and quality of follicles and oocytes may affect the MIV in domestic queens. Additionally, it may assist in the preservation of endangered wild felines
218

Hormonal influences on the maturation of the central nervous system

Adams-Smith, William Nelson January 1965 (has links)
No description available.
219

Inherited predisposition to breast/ovarian cancer : the frequency and nature of BRCA1 gene mutations in South African families

Yawitch, Tali Michelle 21 December 2005 (has links)
Breast cancer is the most common cancer in South African women. Approximately 5¬10% of all breast cancer cases are due to an inherited predisposition, resulting from mutations in tumour suppressor genes. The BRCA1 gene on chromosome 17q is one such tumour suppressor gene, that when mutated confers an increased risk of breast/ovarian cancer in carriers. To date, more than 500 different BRCA 1 mutations have been reported worldwide. Some of these mutations are frequently reported and others occur commonly in certain population groups. These population-specific differences in mutations represent founder effects, whereby a single ancestral mutation accounts for the majority of breast cancer cases. This study was undertaken as the nature and frequency of BRCA1 mutations in South African breast/ovarian cancer families is unknown. Fifty-one breast/ovarian cancer families were screened for three commonly occurring mutations (185deIAG, 4184del4 and 5382insC) using polymerase chain reaction (PCR) and allele-specific oligonucleotide (ASO) hybridisation. The protein truncation test (PTT) was utilised to detect truncating mutations in the large exon 11, and the remaining coding exons were screened for mutations using exon-by-exon PCR single strand conformation polymorphism/heteroduplex analysis (SSCP/HA). Seven disease-causing mutations were identified in 15 families, consisting of five different frameshift mutations and two different nonsense mutations. Four Ashkenazi Jewish families were found to harbour the 185delAG mutation; the 5382insC mutation was identified in two Afrikaner families and one Ashkenazi Jewish family. Haplotype analysis revealed that the four Ashkenazi families share the common Ashkenazi Jewish haplotype, suggesting a common ancestor for these families. Similarly, the two Afrikaner families share the same haplotype as families of north and east European ancestry with the 5382insC mutation. The haplotype of the Ashkenazi Jewish family with this mutation was however different to the linked haplotype, indicating a recombination event or an independent mutation. Both these mutations are thought to have occurred in or before the medieval period. Furthermore, four Afrikaner families were found to carry the novel E881X nonsense mutation, which has not been previously described. Haplotype analysis of these families suggested that these patients share a common ancestor, and genealogic studies have identified the founding couple for this mutation, who both arrived in the Cape from France in the late 1600s. Four additional families were found to harbour BRCA1 mutations by SSCP/HA. Three of these mutations have not been previously reported - the S451X nonsense mutation (identified in a family of Scottish origin), the 1493delC mutation identified in an Afrikaner family, and the 4957insC mutation identified in an Indian family. The 448insA mutation was identified in a family of German origin, where the patient had cancer of the fallopian tubes. A number of different described polymorphisms and variants of unknown functional significance were also identified. This is the first study to show that BRCA1 is involved in South African breast/ovarian cancer families, to the extent that 29.4% (15/51) of families have BRCA1 mutations. Furthermore, minor founder effects in the Afrikaner population have been demonstrated. These results enable improved genetic counselling and clinical management of mutation positive families as well as subsequent testing of family members. / Dissertation (MSc (Human Genetics))--University of Pretoria, 2005. / Genetics / unrestricted
220

The effects of clomiphene citrate on ovarian function in rats

Feng, Tian Bin January 1990 (has links)
In the present study, the effects of clomiphene citrate (CC) on ovulation, ovarian growth and ovarian steroidogenesis were examined. Ovulation in rats in response to PMSG was completely blocked by administration of three daily treatments of 1.0 mg CC/rat, but was restored by administration of hCG as a preovulatory LH surge substitute. When the number of treatment days was reduced to two days, 1.0 mg of CC enhanced ovulation in response to PMSG, whereas treatment for one day with the same dose of CC did not affect ovulation. The effects of CC on ovulation appear to be dose-dependent. The effects of CC on ovarian growth were similar to the effects of CC on ovulation. The ovarian growth induced by PMSG was inhibited by high doses of CC, while a lower dose had no effect. The inhibition of ovarian growth in terms of ovarian weight by a high dose of CC was restored by hCG given as a preovulatory LH surge. Treatment duration with CC appears to have an important influence on ovarian growth. Three daily treatments with high doses of CC significantly inhibited ovarian growth. However, when the number of treatment days was reduced from three to two, the opposite results were obtained in that CC significantly stimulated ovarian growth. The effects of CC on ovarian steroidogenesis in response to PMSG were dose-dependent. A higher dose of CC significantly stimulated estradiol-17β biosynthesis. Clomiphene citrate did not show any inhibitory effects on progesterone production. Progesterone production was stimulated by hCG in CC treated rats. Lower doses of CC stimulated progesterone and androgen production. Further studies on this are necessary. Histological examination of the ovary revealed that CC selectively inhibited the development of nondominant follicles. The dominant follicles were unaffected as for they were able to develop to the mature stage. These results suggest that the effects of CC on ovulation, ovarian growth and ovarian steroidogenesis are dose-dependent and affected by treatment duration. Clomiphene citrate is assumed to exert its action via a gonadotropic mechanism. / Medicine, Faculty of / Obstetrics and Gynaecology, Department of / Graduate

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