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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

The effects of dietary zinc on growth and reproduction of the sea urchin Lytechinus variegatus

Trawick, Kimberly Nichole. January 2009 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed Sept. 2, 2009). Includes bibliographical references (p. 30-36).
32

Effects of dietary carbohydrate on weight gain and gonad production in juvenile sea urchins, Lytechinus variegatus

Taylor, Anna M. January 2006 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2006. / Description based on contents viewed Jan. 29, 2007; title from title screen. Includes bibliographical references (p. 70-78).
33

Estudo morfológico e morfométrico de gônadas da tilápia do Nilo (Oreochromis niloticus) submetidas a tratamentos hormonais com 17 metil testosterona e β – estradiol.

SOARES, Maria Goretti 28 February 2012 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-06-02T14:58:15Z No. of bitstreams: 1 Maria Goretti Soares.pdf: 1480730 bytes, checksum: 0e5f87ec90760f36d90872b5ba99c551 (MD5) / Made available in DSpace on 2016-06-02T14:58:15Z (GMT). No. of bitstreams: 1 Maria Goretti Soares.pdf: 1480730 bytes, checksum: 0e5f87ec90760f36d90872b5ba99c551 (MD5) Previous issue date: 2012-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The global aquaculture is growing faster than any other activity of the primary sector. The Brazil has extremely favorable conditions for fish farming, in addition to the great market potential, the country has favorable climate, good availability of areas, large crops of grain and enviable water potential. Tilapia are native to Africa and Asia Minor. About 70 species are taxonomically classified. The tilapia is widely distributed throughout Brazil and is created in various production systems. The development and intensification of farming are dependent on the successful control and manipulation of some physiological functions, among them, playing. In recent years, research has focused on the demand for reliable methods of producing progeny of individuals of one sex. The most practical technique of obtaining populations monosex tilapia is handling the phenotypic sex of the fish by treatment with sex steroids. This study aimed to evaluate the performance of gonadal growth of Nile tilapia (Oreochromis niloticus) in the first 30 days and final fattening phase; fed with added hormones  -17 methyl testosterone and β - estradiol, used to induce phenotypic sex reversal as well as perform morphological study of the gonads of male and female populations, not undergoing hormonal treatment. The experiment was conducted on the basis of the fish UFRPE and Laboratory of Histology DMFA / UFRPE. A total of 400 adults and 30 larvae of Nile tilapia (Oreochromis niloticus). The larvae were divided into 03 distinct groups: Group T1: 100 animals fed with commercial feed with added β - estradiol (20 mg / kg). T2: 100 animals fed with commercial feed with added 17 -  - methyltestosterone (60 mg / kg) Control Group (CG): 200 animals fed with commercial diet free of additives. Mice from all groups were fed five times a day for 35 days. The adults were cultured for 24 weeks in tanks fed diet added network of hormones in the first 30 days and commercial diet free of additives and specific to each stage of cultivation in the later stages. The histological material was collected, processed and analyzed according to the usual methods for routine histology. Statistical analyzes were applied ANOVA Tukey.c / A aquicultura mundial está crescendo mais rápido do que qualquer outra atividade do setor primário. O Brasil reúne condições extremamente favoráveis à piscicultura, além do grande potencial de mercado, o país conta com clima favorável, boa disponibilidade de áreas, grandes safras de grãos e invejável potencial hídrico. As tilápias são nativas do continente africano e da Ásia menor. Cerca de 70 espécies estão taxonomicamente classificadas. A tilápia está amplamente distribuída pelo território brasileiro e é criada nos mais diversos sistemas de produção. O desenvolvimento e a intensificação da piscicultura são dependentes do sucesso no controle e manipulação de algumas funções fisiológicas e, dentre elas, a reprodução. Nos últimos anos, as pesquisas têm se voltado para a procura de métodos confiáveis de produção de progênies de indivíduos de um determinado sexo. A técnica mais prática de se obter populações monosexo de tilápias é a manipulação do sexo fenotípico do peixe, pelo tratamento com esteróides sexuais. O presente trabalho teve por objetivo, avaliar o desempenho do crescimento gonadal da tilápia do Nilo (Oreochromis niloticus) nos primeiros 30 dias de vida e fase final de engorda; alimentadas com rações adicionadas dos hormônios -17 metil testosterona e β – estradiol, utilizados para indução da reversão sexual fenotípica, bem como realizar estudo morfológico das gônadas de populações de machos e fêmeas, não submetidos a tratamento hormonal. O experimento foi realizado na base de piscicultura da UFRPE e no Laboratório de Histologia do DMFA/UFRPE. Foram utilizadas 400 larvas e 30 adultos de tilápia do Nilo (Oreochromis niloticus). As larvas foram divididas em 03 grupos distinto :Grupo T1: 100 animais alimentados com ração comercial adicionada de β – estradiol (20 mg/kg). Grupo T2: 100 animais alimentados com ração comercial adicionada de 17 -  - metiltestosterona (60 mg/kg) Grupo Controle (GC): 200 animais alimentados com ração comercial livre de aditivos. Os animais de todos os grupos foram alimentados 5 vezes ao dia, durante 35 dias. Os adultos foram cultivados por 24 semanas em tanques rede recebendo ração adicionada de hormônios nos primeiros 30 dias e ração comercial livre de aditivos e específica para cada fase de cultivo nas fases seguintes. O material histológico foi, coletado, processado e analisado de acordo com os métodos usuais de rotina para histologia. Para análise estatística foram aplicados os testes de ANOVA de Tukey.
34

Endokrinologie en histomorfologie van die gonades van Cyprinus carpio L.

Fouché, Chris Henri 13 May 2014 (has links)
M.Sc. (Zoology) / The histomorphology of the ovaries of Cyprinus carpio L., as well as the histomorphological changes that occur in these ovaries during the breeding cycle, were investigated. Concurrently, the blood plasma and ovarian cytosol were analized for the presence of gonadotropin (GtH), FSH, LH, Oestriol, Cortisol and Progesterone, with the aid of Test Kits which are commonly used for determining the levels of these hormones in human blood plasma. C. carpio possesses cystovaria which are continuous with the oviducts which unite before opening to the exterior via a gonopore. The results clearly show that C. carpio has a four season breeding cycle and that egg laying occurs during Spring and Summer. Furthermore morphological changes of the ovary (which occurred during the breeding cycle) as well as the oocyte developmental stages, closely resemble those respectively described for teleosts in general by Kesteven (1960) and Malhotra et al., (1978). The endocrinological tests clearly indicated the presence of GtH, FSH, LH, Oestriol and Cortisol, while all the tests for Progesterone were negative. A comparison between the presence of the abovementioned hormones and the histomorphological development of the ovaries during the breeding cycle indicate that the endocrinological control mechanisms are similar to those which have been described for other teleosts. However, a clear distinction was found between FSH and LH which is a possible indication that C. carpio does not possess a single gonadotropin, but rather that FSH and LH have evolved in this species.
35

The effect of photoperiod on the gonads and basophilic adenohypophyseal cells of the rough-skinned newt, Taricha granulosa granulosa

Coambs, Paul Patton 01 January 1970 (has links)
The function of light in the reproductive cycle in amphibians has not been extensively studied. However, Farner (1965) feels that the small amount of experimental evidence suggests that photoperiod may play a role in the testicular cycle of Rana esculenta. The purpose of this paper is to study the effect of light on the gonads and the gonadotropic hormone forming cells of the adenohypophysis in the newt Taricha granulosa granulosa.
36

Seasonal gonadal changes of adult oviparous oysters in Tomales Bay

Berg, Carl John 01 January 1968 (has links)
Two species of oviparous oysters, Crassostrea virginica (Gmelin, 1790), the Eastern oyster, and Crassostrea gigas (Thunbert, 1793), the Japanese oyster, were introduced into Tomales Bay, California, for commercial purposes. Because these oysters do not propagate in Tomales Bay, new shipments of adult oysters or oyster spat must be periodically sent from the east coast of the United States or from Japan. It is the purpose of this study to compare the seasonal gonadal changes which occur in the two species of adult oysters in Tomales Bay with one another, and to compare them with the seasonal gonadal changes which occur in the same species of oysters in other regions. The differences in gonadal changes will be related to variances in environmental conditions and to specific or racial characteristics. The introduction of oysters into a new environment is valuable for both commercial and scientific reasons. Although it has long been known that C. virginica and C. gigas do not propagate in Tomales Bay, no one has ever done a detailed study of their reproductive cycle or the seasonal histological changes in their gonads. This study, therefore, extends the knowledge concerning an oyster's reaction and adaptation to its new environment.
37

Avaliação da função gonadal em pacientes do sexo masculino com dermatomiosite e polimiosite / Gonadal function evaluation in male patients with dermatomyositis and polymyositis

Moraes, Ana Julia Pantoja de 20 January 2009 (has links)
Objetivo: Avaliar a função gonadal de homens com miopatias inflamatórias idiopáticas (MII). Métodos: Vinte e cinco pacientes com MII foram avaliados e comparados com 25 homens saudáveis. Os pacientes foram subdivididos em dois sub-grupos de acordo com as alterações dos espermatozóides: grupo A (n=10, duas ou mais das seguintes alterações: terato/oligo/astenozoospermia ou azoospermia) e grupo B (n=15, teratozoospermia). Foram realizados: exame urológico, ultra-sonografia testicular, análise dos espermatozóides (critérios da OMS e Kruger), pesquisa dos anticorpos anti-espermatozóides e dosagens hormonais Nos subgrupos foram também avaliados: Disease Activity Score (DAS), Visual Analogue Scale (VAS), Manual Muscle Testing (MMT), myositis disease activity assessment visual analogue scales (MYOACT), myositis intention to treat activity index (MITAX), Myositis damage index [MDI], enzimas musculares e tratamento. Resultados: Pacientes apresentaram alterações nos espermatozóides comparados com controles com freqüência maior de nível elevado de FSH (20% versus 0%, p=0,05). O sub-grupo A apresentou freqüência e mediana maior do nível de CK (p=0,001 e p=0,001) assim como DAS (p=0,01), VAS (p=0,051), MMT (p=0,003). As medianas dos volumes testiculares foram menores no grupo A (direito, p=0,015 e esquerdo, p=0,025). As medianas dos parâmetros espermáticos foram reduzidas no grupo A [contagem total (p=0,0001); motilidade (p=0,0001); morfologia pela OMS (p=0,0001) e por Kruger (p=0,0001). A mediana de FSH foi elevada (p=0,035) e de androstenediona foi reduzida (p=0,02) no sub-grupo A. Afrequência de ciclofosfamida foi similar nos grupos (30% versus 6%, p=0,26). Conclusões: Atividade da doença foi o principal fator contribuinte para disfunção gonadal. Hipogonadismo hipergonadotrófico pode explicar as alterações anatômicas e funcionais observadas / Objective: To perform a global gonad evaluation in male idiopathic inflammatory myopathies (IIM) patients. Methods: Twentyfive consecutive IIM were compared to 25 age-matched healthy subjects. Patients were subdivided in two groups according to the severity of sperm abnormalities: group A (at least two of the following terato/oligo/asthenozoospermia or azoospermia) and group B (teratozoospermia). Patients and controls underwent a systematic assessment consisting of: urologic examination, testicular ultrasound, semen analysis and hormones. Patients´ serum CK levels, visual analogue scale (VAS), disease activity score (DAS), manual muscle testing (MMT), myositis disease activity assessment visual analogue scales (MYOACT), myositis intention to treat activity index (MITAX), and Myositis damage index (MDI) were evaluated. Results: Several sperm variables were significantly altered compared to controls (p<0.05). The subgroup analysis according to the severity of sperm alterations revealed that the frequency of elevated CK and its median level was significantly higher in group A (p=0.001 and p=0.001), as also was DAS, VAS and MMT (p=0.01; p=0.051 and p=0.03). The median of testicular volumes were lower in group A (right p=0.015 and left p=0.025). All median sperm parameters were lower in group A (total sperm count, p=0.0001; total motile sperm count, p=0.0001; and sperm morphology by Kruger p=0.0001 and WHO p=0.0001). Higher median FSH (p=0.035) and lower median androstenedione levels (p=0.02) were observed in group A. The frequency of cyclophosphamide was similar in both groups (30% vs. 6%, p=0.26). Conclusions: Active disease was the major contributing factor for severe gonad dysfunction. The hypergonadotrophic hypogonadism may explain the anatomical and dysfunctional alterations observed
38

Avaliação da função gonadal em pacientes do sexo masculino com dermatomiosite e polimiosite / Gonadal function evaluation in male patients with dermatomyositis and polymyositis

Ana Julia Pantoja de Moraes 20 January 2009 (has links)
Objetivo: Avaliar a função gonadal de homens com miopatias inflamatórias idiopáticas (MII). Métodos: Vinte e cinco pacientes com MII foram avaliados e comparados com 25 homens saudáveis. Os pacientes foram subdivididos em dois sub-grupos de acordo com as alterações dos espermatozóides: grupo A (n=10, duas ou mais das seguintes alterações: terato/oligo/astenozoospermia ou azoospermia) e grupo B (n=15, teratozoospermia). Foram realizados: exame urológico, ultra-sonografia testicular, análise dos espermatozóides (critérios da OMS e Kruger), pesquisa dos anticorpos anti-espermatozóides e dosagens hormonais Nos subgrupos foram também avaliados: Disease Activity Score (DAS), Visual Analogue Scale (VAS), Manual Muscle Testing (MMT), myositis disease activity assessment visual analogue scales (MYOACT), myositis intention to treat activity index (MITAX), Myositis damage index [MDI], enzimas musculares e tratamento. Resultados: Pacientes apresentaram alterações nos espermatozóides comparados com controles com freqüência maior de nível elevado de FSH (20% versus 0%, p=0,05). O sub-grupo A apresentou freqüência e mediana maior do nível de CK (p=0,001 e p=0,001) assim como DAS (p=0,01), VAS (p=0,051), MMT (p=0,003). As medianas dos volumes testiculares foram menores no grupo A (direito, p=0,015 e esquerdo, p=0,025). As medianas dos parâmetros espermáticos foram reduzidas no grupo A [contagem total (p=0,0001); motilidade (p=0,0001); morfologia pela OMS (p=0,0001) e por Kruger (p=0,0001). A mediana de FSH foi elevada (p=0,035) e de androstenediona foi reduzida (p=0,02) no sub-grupo A. Afrequência de ciclofosfamida foi similar nos grupos (30% versus 6%, p=0,26). Conclusões: Atividade da doença foi o principal fator contribuinte para disfunção gonadal. Hipogonadismo hipergonadotrófico pode explicar as alterações anatômicas e funcionais observadas / Objective: To perform a global gonad evaluation in male idiopathic inflammatory myopathies (IIM) patients. Methods: Twentyfive consecutive IIM were compared to 25 age-matched healthy subjects. Patients were subdivided in two groups according to the severity of sperm abnormalities: group A (at least two of the following terato/oligo/asthenozoospermia or azoospermia) and group B (teratozoospermia). Patients and controls underwent a systematic assessment consisting of: urologic examination, testicular ultrasound, semen analysis and hormones. Patients´ serum CK levels, visual analogue scale (VAS), disease activity score (DAS), manual muscle testing (MMT), myositis disease activity assessment visual analogue scales (MYOACT), myositis intention to treat activity index (MITAX), and Myositis damage index (MDI) were evaluated. Results: Several sperm variables were significantly altered compared to controls (p<0.05). The subgroup analysis according to the severity of sperm alterations revealed that the frequency of elevated CK and its median level was significantly higher in group A (p=0.001 and p=0.001), as also was DAS, VAS and MMT (p=0.01; p=0.051 and p=0.03). The median of testicular volumes were lower in group A (right p=0.015 and left p=0.025). All median sperm parameters were lower in group A (total sperm count, p=0.0001; total motile sperm count, p=0.0001; and sperm morphology by Kruger p=0.0001 and WHO p=0.0001). Higher median FSH (p=0.035) and lower median androstenedione levels (p=0.02) were observed in group A. The frequency of cyclophosphamide was similar in both groups (30% vs. 6%, p=0.26). Conclusions: Active disease was the major contributing factor for severe gonad dysfunction. The hypergonadotrophic hypogonadism may explain the anatomical and dysfunctional alterations observed
39

Impact de l’exposition in utéro aux analgésiques et anti-inflammatoires non stéroïdiens sur le développement précoce et la maturation des organes reproducteurs mâles chez la souris / Risks of in utero analgesics and non steroidal anti-inflammatory exposure on the early development and maturation of the male reproductive organs in mice

Rossitto, Moïra 09 December 2016 (has links)
Les analgésiques tel que le paracétamol, ou acétaminophène (ACE), et les anti-inflammatoires non stéroïdiens (AINS) comme l’aspirine et l’ibuprofène, sont largement utilisés dans le monde pour soulager douleur, fièvre ou inflammation. Ces médicaments, vendus sans ordonnance et souvent pris en automédication, sont de plus en plus utilisés par les femmes enceintes depuis les années 1990, notamment aux États-Unis et en Europe. De nombreuses études de cohorte ont mis en avant l’association entre la prise de ces molécules par les femmes durant le premier et deuxième trimestre de grossesse, et l’apparition de malformations congénitales des organes reproducteurs des garçons nouveau-nés, comme la cryptorchidie ou l’hypospadias. Ces analgésiques inhibent l’activité enzymatique des cyclooxygénases (Cox), qui catalysent l’étape clef de la voie de biosynthèse des prostaglandines (PGs), dont la prostaglandine D2 (PGD2), impliquée dans la détermination sexuelle des lignées somatique et germinale de la gonade mâle chez la souris. Afin d’étudier si la gonade embryonnaire peut constituer une cible de ces molécules, l’objectif principal de cette thèse a été d’analyser l’impact de l’exposition in utero à l’ACE, l’aspirine et l’ibuprofène seuls ou en combinaison, pendant la période de détermination sexuelle (de 10,5 à 13,5 jours post coitum (jpc) chez la souris). Des doses « thérapeutiques » similaires à celles utilisées chez l’Homme ont été administrées par voie orale. Mon travail a permis de démontrer que l’exposition in utero à la combinaison des deux drogues ACE et ibuprofène induisait, dans le testicule embryonnaire, une accélération de la différenciation de la lignée germinale du testicule embryonnaire, précurseurs des gamètes à l’âge adulte, par le biais d’une reprogrammation épigénétique avancée, ainsi qu’une augmentation du stockage du glycogène dans les cordons testiculaires, via l’activation de l’expression des gènes de la matrice extracellulaire. De plus, ce projet a permis d’identifier pour la première fois le profil d’expression des prostaglandines dans le testicule embryonnaire de souris. Dans un deuxième temps, l’impact de l’exposition in utero à ces drogues sur la stéroïdogenèse a été étudié, en parallèle avec l’étude sur le rôle de la PGD2 dans les cellules stéroïdogènes (cellules de Leydig) dans le testicule fœtal de souris à 17,5 jpc. Ces résultats pourraient conduire à modifier l’utilisation de ces médicaments chez la femme, au cours des deux premiers trimestres de grossesse. / Mild analgesics such as paracetamol, or acetaminophen (ACE), and nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen, are widely used worldwide for relieving pain, fever or inflammation. These over-the-counter drugs are often taken as self-medication, and are increasingly used by pregnant women since the 1990s, particularly in the United States and Europe. Many cohort studies have highlighted the association between intake of these molecules by women during the first and second trimester of pregnancy, and the occurrence of birth defects of the reproductive organs of newborn boys, such as cryptorchidism or hypospadias. These analgesics inhibit the enzymatic activity of cyclooxygenases (Cox), which catalyze key step in the biosynthetic pathway of prostaglandins (PGs), whose prostaglandin D2 (PGD2), involved in the male sex determination of both somatic and germinal lineages in mice. To investigate whether the embryonic gonad can be a target of these molecules, the main objective of this thesis was to analyze the impact of in utero exposure to ACE, aspirin and ibuprofen alone or in combination, during the period of sex determination (10.5 to 13.5 days post coitum (dpc) in mice). "Therapeutic" doses similar to those used in humans were orally administered. My work has shown that in utero exposure to the combination of both ACE and ibuprofen drugs induced acceleration of the differentiation of the embryonic testis germline, the precursors of gametes in adulthood, through an advanced epigenetic reprogramming, and an increase of glycogen storage in the testicular cords, via activation of extracellular matrix gene expression. In addition, this project has identified for the first time the profile of prostaglandins expression in mouse embryonic testis. Secondly, the impact of in utero exposure to these drugs on steroidogenesis was evaluated, in parallel with the study on the role of PGD2 in steroidogenic cells (Leydig cells) in mouse fetal 17.5 dpc testis. These results could lead to change the use of these drugs in women, during the first two trimesters of pregnancy.
40

Vliv syntetického progestinu etonogestrelu na sekundární pohlavní znaky a histologii gonád živorodky Wingeovy (Poecilia wingei)

PECH, Michal January 2019 (has links)
Synthetic progestins are steroid hormones, which are not only part of the hormonal contraceptives, but they are also used to treat a number of health problems in human. Due to the widespread use of progestin-based drugs, their residues are being found in wastewaters, from where they also enter into the wastewater treatment plants and surface waters. The aim of this thesis was to assess whether the synthetic progestin etonogestrel affects the secondary sexual characteristics and gonad histology of Endler´s guppy (Poecilia wingei). During the experiment, males and females were separately exposed to 3.2 and 320 ng.l-1 etonogestrel for 34 days. A group of fish reared in pure water (K) and group of fish reared in pure water containing the solvent dimethylsulfoxide (KS) served as controls. At the end of the test, all the fish were photographed to capture any color changes. Then the fish were sacrificed and fixed in 10 % buffered formalin solution for morphometric and histological analysis. Fish samples taken for morphometric analysis were photographed using QuickPHOTO MICRO 2.3 software and individual morphometric parameters were measured on the images taken. Fish sample processing for histological analysis included decalcification, dehydration, and pouring of the samples into paraffin blocks. Then paraffin blocks were cut with the thickness of about 4.5 um, resulting slides were stained with hematoxylin and eosin. Histological changes of the gonads were determined on the histological samples prepared in this way. In females exposed to both concentrations of etonogestrel occurrence of color spots was observed. Color spots are characteristic for male and in females indicate masculinization. In addition, females exposed to 320 ng.l-1 etonogestrel showed a change in anal fin morphometry to a gonopodium-like structure (modified anal fin of males serving as helping copulatory organ), a sign also suggesting masculinization. Furthermore, exposure of etonogestrel in both lower and higher concentration of etonogestrel reduced number of mature oocytes in the ovaries, and their occurrence decreased with increasing concentration. In males exposed to both concentrations of etonogestrel a smaller ratio of the length of 4th ray to the length of 6th ray of gonopodium was found. In addition, at concentration of etonogestrel 320 ng.l-1 a greater ratio of the length of 6th ray to body length and extension of length of 6th ray was observed. Although there were no changes, which would indicate hypermasculinization, these changes could have a negative impact on reproduction, or sexual selection by the female. Etonogestrel exposure had no effect on the normal development of testes, because predominantly mature spermatophores were found in males of all treatment groups. Based on these findings, we can say that etonogestrel, like other progestins, represents a real risk to fish if it occures in aquatic environment at concentrations reaching units of ng.l-1.

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