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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.
131

Scotland the new melting pot? /

Rovatsos, Alexandria. January 2007 (has links)
Theses (M.A.)--Marshall University, 2007. / Title from document title page. Includes abstract. Document formatted into pages: contains v, 40 pages. Bibliography: p. 36-40.
132

Investigation of factors affecting fertility chromosome segregation errors and environmental toxins /

Jackson, Jodi Michelle. January 2007 (has links)
Thesis (Ph. D.)--Case Western Reserve University, 2007. / [School of Medicine] Department of Genetics. Includes bibliographical references. Available online via OhioLINK's ETD Center.
133

Use of Inbred Strains of Mice to Study the Genetics and Biology of Sperm Function

Byers, Shannon L. January 2006 (has links) (PDF)
No description available.
134

The medicalization of infertility and its ethical implications

Hamid, Cherine January 1994 (has links)
Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02
135

Endocrine control of ovulation rate in the cow

Price, Christopher Alan January 1987 (has links)
Techniques to increase prolificacy in cattle have met with limited success; the aim of these studies was to investigate the potential of actively immunising cattle against certain gonadal hormones, and to examine the physiological basis of these treatments. Eight heifers were immunised against 8mg of a testosterone conjugate in Freund's Incomplete Adjuvant, & nine animals served as controls. These heifers were given one priming and two booster injections at four-month intervals. After the last booster injection, 7/8 animals had become anoestrous, and displayed significantly raised blood progesterone & mean LH concentrations,increased LH pulse frequency, & decreased mean FSH concentrations. Seven months after this treatment, 3/7 anoestrous heifers resumed ovarian cyclicity, with a mean ovulation rate of 2.7+0.7. To determine if the different ovarian responses observed above could be obtained by changes of ovarian steroid feedback seen during the oestrous cycle, groups of 6 heifers were implanted with large,medium or small sized oestradiol capsules during the luteal phase of the cycle. Five control heifers received empty implants. During the luteal phase of the cycle following implantation, all heifers were ovariectomised. The effect of the treatment on ovarian function and gonadotrophin secretion in the presence or absence of progesterone (PRID) was then determined. Increasing physiological concentrations of oestradiol reduced the number of large antral follicles and corpora lutea, but not the total number of antral follicles >lmm diameter. A combination of progesterone and oestradiol were fully effective in maintaining luteal-phase concentrations of LH and FSH, and follicular-phase concentrations of oestradiol alone were able to maintain LH and FSH concentrations within the physiological range. Thus changes of blood steroid levels similar to those seen during the oestrous cycle may interrupt ovarian function. Cattle were therefore immunised against a non-steroidal, partly purified fraction of ovine follicular fluid (PPFF) enriched ininhibin-like activity as measured in vivo and in vitro. Active immunisation against 0.4mg and 4mg ovine PPFF produced 1/5 & 3/5 heifers with multiple ovulations, respectively; this was not associated with changes of FSH secretion. To examine in more detail the endocrine responses to this treatment, and to investigate possible comparative aspects, cows were immunised against 4mg ovine, porcine or equine PPFF. No treatment increased ovulation rate, but the porcine-PPFF immunised heifers showed a 7-fold increase in mean LH secretion that could not be explained by alterations in pulsatile secretion or in steroid feedback. Collectively, these results suggest that the cow does not respond consistently to treatments so far designed to alter gonadotrophin secretion, that inhibin is not a major feedback hormone in this species, and that the heifer may possess an influential intra-ovarian control mechanism which ultimately determines ovulation rate.
136

Chinese Immigrants’ Fertility Behaviour in Canada

Wang, Xiaoxi 12 December 2018 (has links)
China is one of the top three sources of immigrants to Canada (Statistics Canada, 2016a). As a result, many scholars now recognize the importance of studying Chinese immigrants (Guo, 2013; Mah, 1995; Chow, 2004; Fong & Ooka, 2006; Tang, 2001; Mao, 2015). However, so far, most studies have focused only on this group’s economic attainment, their educational performance, and their sociocultural dynamics. As yet, there has been little discussion of their fertility. Indeed, in my opinion, far too little attention has been paid to the upbringing of these immigrants in the context of China’s unique efforts at population control, culminating in the official One-Child Policy of 1979. Therefore, this study aims to answer the following three research questions about Chinese immigrants living in Canadian society: • Do the Chinese immigrants conceive their fertility with reference to the One-child policy? • What factors do they attribute to this policy, either as benefits or as drawbacks, in terms of their fertility? • Do their discourses reveal any evidence of internalization of the One-child policy, despite their exposure to competing fertility norms in Canada? Or on the contrary, has the immigration process disrupted their subscription to the one-child norm? My study draws on fifteen semi-structured interviews with Chinese immigrant women. This paper presents its main results as the following: 1) the one-child policy has indeed influenced Chinese people’s view of fertility, which since 1982 has changed from a pronatalist philosophy to one favouring fewer births; 2) Chinese immigrants to Canada have in fact internalized the one-child norm; 3) The experience of immigration has not disrupted the one-child habitus. Rather, the immigrants’ exposure to the Canadian environment—in terms both of workplace and community—has contributed to its reinforcement. Of course, it may not be possible to generalize from the results of my local research (conducted in Ottawa, Ontario) to all immigrant women across the country. Nevertheless, I am confident that this study will prove to be a valuable contribution to discussions on the issue of Chinese fertility in Canada.
137

Fertility and education: the case of Ghana

Timbilla, Rahinatu January 2013 (has links)
The study attempts to find the relationship between education and fertility in Ghana, as Ghana wants to reduce its fertility rates from 4.0 to 3.0 replacement levels which will help to move the country into middle income status. A country that has a stable population growth is able to plan and allocate resources to its populace more effectively. High fertility rates have consequences for food security, social & economic opportunities and overall economic wellbeing of the population. The study sets outs to investigate the linkages or factors that help in reducing fertility rates, education is one major factor that has been found be to be inversely related to fertility. Does this relationship exist in Ghana? Has education in any way contributed to the recent fertility declines in Ghana? And by how much did education contribute. Finally, are there other factors that have contributed to the recent fertility decline in Ghana? To answer the questions, the study takes advantage of an educational reform program in 1987/88 that saw mass construction of schools, training of teachers and provision of study materials to estimate the impact of education on fertility. Using difference-in-difference approach and 2SLS, the study finds that the National Education Reform program lead to reductions in early births...
138

The decline of fertility in Scotland

Morse, Donald John January 1988 (has links)
No description available.
139

EFFICIENCY AND SAFETY OF FERTILITY PRESERVATION AND PREGNANCIES IN YOUNG BREAST CANCER PATIENTS

Goldrat, Ornite 11 January 2018 (has links)
Résumé: Lorsqu’une femme en âge de reproduction est diagnostiquée avec un cancer du sein, le traitement comprend entre autres de la chimiothérapie et/ou une hormonothérapie. Malheureusement, certaines patientes deviendront infertiles suite à la chimiothérapie qui est gonadotoxique, ce qui diminue leurs chances de devenir mères avec leurs propres gamètes. Etant donné que la grossesse après un cancer du sein n’est plus considérée comme un facteur de risque de récidive de la maladie, l’accès à la maternité chez ces jeunes patientes est devenu un enjeu majeur. Cependant, peu de données ont été publiées concernant la sécurité de concevoir grâce à la PMA chez une patiente devenue infertile suite au traitement du cancer du sein.Il est donc primordial d’offrir aux femmes qui le désirent une méthode de préservation de la fertilité avant tout traitement gonadotoxique.La conservation d’ovocytes ou d’embryons après hyperstimulation ovarienne est une des techniques offertes aux patientes. Néanmoins, en cas de maladie hormono- sensible tel que le cancer du sein, une élévation d’hormones stéroïdiennes accompagnant la réponse ovarienne est peu souhaitable. Des protocoles modifiés ont donc été développés, tel que l’hyperstimulation ovarienne aux gonadotrophines associée au letrozole, un inhibiteur de l’aromatase.Malgré certains résultats rassurants dans la littérature, les données concernant l’efficacité et la sécurité de ce protocole sont toutefois limitées.Notre projet comporte 2 objectifs:1. Evaluation d’une procédure de préservation de la fertilité associant une hyperstimulation ovarienne au letrozole (Let-COH), dans une étude prospective non randomisée (BROVALE).2. Evaluation de la sécurité de la grossesse associée à la PMA chez des patientes ayant été traitées pour un cancer du sein.Dans la première partie nous avons confirmé l’efficacité du Let-COH sur base du taux de maturation ovocytaire similaire à une population contrôle de patientes7infertiles ayant bénéficié d’une hyperstimulation ovarienne conventionnelle sans letrozole (groupe contrôle) quel que soient les modes de déclenchement de la maturation ovocytaires utilisés, human chorionic gonadotropin (hCG) ou l’agoniste de la gonadotropin-releasing hormone (GnRHa). Par ailleurs, les modifications endocriniennes dans le liquide folliculaire, et l’expression de gènes liés à la qualité ovocytaire au niveau des cellules du cumulus oophorus (CC) ont été analysées. Dans le microenvironnement entourant l’ovocyte, nous avons observé un taux d’œstradiol significativement plus bas et un taux de testostérone significativement plus élevé dans le groupe Let-COH, comparé au groupe contrôle. Par ailleurs, l’expression génique au niveau des CC était plus basse dans le groupe Let-COH déclenché à l’hCG comparé au groupe contrôle. Cependant l’inverse était observé lorsque le GnRHa était utilisé comme déclencheur de l’ovulation. Ces résultats suggèrent donc un effet bénéfique des analogues de la GnRH sur la qualité ovocytaire avec le Let-COH.Nous avons montré que le taux d’oestradiol était bas durant la stimulation, mais que le taux de progestérone durant la phase lutéale était supra-physiologique chez les patientes ayant reçu le Let-COH, comparable au taux des patientes contrôles.Etant donné le rôle potentiel de la progestérone dans la carcinogenèse mammaire, nous avons modifié le protocole de déclenchement de l’ovulation, pour administrer le GnRHa au lieu de l’hCG.Dans la seconde partie de notre travail, nous avons réalisé une étude rétrospective multicentrique afin de comparer les issues oncologiques et de grossesse de patientes ayant été enceintes après cancer du sein, naturellement (n=173) ou grâce à la PMA (n=25). Malgré la petite taille de l’échantillon obtenu, nous n’avons pas observé plus de récidives chez les patientes ayant eu recours à la PMA.En conclusion, ce projet nous a permis de démontrer l’efficacité de la préservation de la fertilité chez les jeunes patientes atteintes de cancer du sein, par hyperstimulation associée au letrozole. Nous avons également observé que le risque de récidive de la maladie n’était pas majoré dans notre échantillon limité de patientes enceintes suite à la PMA après cancer du sein. / Abstract:Young women diagnosed with breast cancer are often treated with adjuvant primary therapy, including chemo and/or endocrine therapy. These women may face infertility or premature ovarian failure due to the gonadotoxicity of chemotherapy regimens or to aging, which significantly decreases their chances to become mothers with their own gametes. Since it has been established that pregnancy after breast cancer does not increase the risk of relapse, assisting young breast cancer survivors to access motherhood has become a major quality of life issue. However, data on the safety of pregnancies associated with ART in patients who became infertile are scarce. Therefore, it is recommended that young patients diagnosed with breast cancer be informed about treatment-related infertility risks and available procedures to preserve their fertility before undergoing gonadotoxic treatment.Oocyte and/or embryo cryopreservation following controlled ovarian hyperstimulation (COH) is the most established fertility preservation procedure that patients can undergo before initiation of chemotherapy. However, this procedure induces an increase in steroid levels, which may be detrimental in hormonally sensitive diseases such as breast cancer. In order to avoid this issue, a modified protocol has been developed a decade ago, combining letrozole (an aromatase inhibitor) with conventional COH (Let-COH).Despite recent reassuring preliminary results reported in the literature, data are still very limited regarding the efficiency and the safety of this protocol.Thus, the aims of this project were:1. Evaluation of the efficiency of Let-COH before adjuvant therapy, in anonrandomized prospective study (BROVALE).2. Evaluation of the safety of ART-associated pregnancy in breast cancersurvivors.In the first part, we confirmed the efficiency of Let-COH (study group) based on similar oocyte maturation rates when compared to infertile patients undergoing conventional COH without letrozole (control group), regardless of the triggering5method, human chorionic gonadotropin (hCG) or GnRH-agonist (GnRHa). Oocyte quality was indirectly assessed by analysis of follicular fluid (FF) steroid levels and cumulus cell (CC) gene expression (HAS2, PTGS2, and GREM1). We found that estradiol levels were significantly lower and testosterone levels significantly higher in the study compared to the control group, suggesting lower oocyte quality. Nevertheless, when GnRHa was used as ovulation trigger, differences in estradiol levels between the groups were reduced. Similarly, CC gene expression was lower in the study group compared to the control group in the hCG triggered subpopulation, while the opposite effect was observed in the GnRH-agonist triggered subpopulation. Altogether, the results suggest a benefit of GnRHa trigger on oocyte quality in Let- COH protocol.The safety of the protocol was assessed by measuring estradiol and progesterone levels during and after Let-COH. We confirmed that estradiol levels remained low during treatment. However, during luteal phase, progesterone levels were comparable to conventional COH when triggered with hCG, but not with GnRHa. Since progesterone may be as important as estradiol in promoting breast carcinogenesis, we modified the protocol to systematically use GnRH-agonist as ovulation trigger.In the second part of our project, we conducted a retrospective multicenter study to compare pregnancy and oncological outcomes among breast cancer survivors who subsequently conceived spontaneously (n=173) or following ART (n=25). Although the ART group’s sample size was small, we did not observe an increased relapse rate after ART compared to patients who conceived naturally.In conclusion, we confirmed the feasibility and efficiency of Let-COH as a method of fertility preservation in breast cancer patients. Moreover, in our small series of ART- associated pregnancies in breast cancer survivors we did not observe an increased risk of disease recurrence. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished
140

Drop-out mayors and graduate farmers: Educational fertility differentials by occupational status and industry in six European countries

Barakat, Bilal, Durham, Rachel Elise 18 June 2013 (has links) (PDF)
Background: Understanding the relationship of education to fertility requires the disentangling of the potentially confounding effect of social status, which is highly correlated with education. Objective: We contribute to this aim by examining educational fertility differentials within occupational groups and industries across a broad swath of Central and Eastern Europe, specifically Austria, Greece, Hungary, Romania, Slovenia, and Switzerland. Methods: Cross-sectional individual-level census samples from the Integrated Public Use Microdata Series (IPUMS) are sufficiently large to contain sizeable numbers of unusual combinations, e.g., university graduates in low-status jobs or primary school dropouts in professional categories. Completed cohort fertility, as well as the share childless and with high parity, are regressed on effects for educational attainment, occupation, industry, and all their interactions within a Bayesian framework, and the contributions to the outcome variation are analysed. Results: Education has a strong, consistent association with fertility outcomes when industry and occupation are held constant. Furthermore, fertility by industry and occupation yields fairly disparate patterns. We also find that differences in completed fertility across countries can be attributed to country-specific compositional differences in education, industry, and occupation, and to interaction effects. However, differences by country in the baseline rate of childlessness and high parity cannot be attributed to such compositional effects. Conclusions: The educational fertility gradient in the settings studied cannot be attributed to an occupational composition effect. (authors' abstract)

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