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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.
221

Sperm cryopreservation and artificial insemination at Groote Schuur Hospital.

Wiswedel, Klaus 06 April 2017 (has links)
The diagnosis and therapy managed by the specialities of infertile couples is traditionally of Gynaecology and Andrology. The latter is a subspeciality, which should combine the knowledge of urologists and gynaecologists in the treatment of sub or infertile men.
222

The prevalence of intact spermatozoa on intimate smear and extract slides: a retrospective case review and re-evaluation of time since intercourse estimation

Rogers, Caitlin Eileen 22 January 2016 (has links)
Literature concerning the time frames for detection of various seminal components commonly tested for in forensic laboratories in sexual assault cases is limited in quantity and in scope. Determining a more accurate time since intercourse (TSI) interval based on an extensive review of forensic case work would provide investigators with a tool for estimating the time elapsed between the occurrence of a sexual assault and the collection of a Sexual Assault Evidence Collection Kit (SAECK) which could be vital information in certain cases. This study demonstrates that the presence of intact spermatozoa is a significant finding on microscope slides prepared from vaginal, anorectal, and oral swabs and that the percentage of intact sperm cells decreases over time. This study also proved that sperm tails are lost during the preparation of microscope slides from SAECK swabs by directly comparing medical personnel-prepared smear slides and analyst-prepared extract slides from 95 Boston Police Department (BPD) Crime Laboratory Unit cases. Additionally, this study presents maximum TSI values for the persistence of sperm heads, intact spermatozoa, and prostate specific antigen (P30) through a retrospective examination of 355 cases processed by the BPD Crime Laboratory Unit over 5 years. The maximum persistence values for P30 in the vaginal, anorectal, and oral cavities were 19 hours, 17 hours, and 20 hours, respectively. In the vaginal cavity, maximum persistence values for intact spermatozoa were 43 hours for smear slides and 41.5 hours for extract slides. The maximum persistence of sperm heads was equivalent for vaginal smear and extract slides at 105 hours. In the anorectal cavity, maximum persistence values for intact spermatozoa were 43 hours for smear slides and 13 hours for extract slides. The maximum persistence of sperm heads was equivalent for anorectal smear and extract slides at 43 hours. In the oral cavity, maximum persistence values for intact spermatozoa were 3.75 hours for smear slides and 5 hours for extract slides. The maximum persistence of sperm heads were equivalent for oral smear and extract slides at 24 hours.
223

Sperm Proteins and Chromatin Dynamics associated with Male Fertility

Dogan, Sule 11 May 2013 (has links)
The impacts of the paternal genome and proteins transferred to the oocyte through spermatozoa cannot be neglected during mammalian embryonic development. Studies over the past 40 years suggest that sperm chromatin alterations (such as DNA fragmentation induced by either chromatin condensation errors, apoptosis and/or oxidative stress) might be negatively associated with fertilization and early embryonic development [1, 2], [3] [4].However, precise molecular mechanisms by which sperm chromatin integrity and sperm proteins impact early embryonic development still remain unclear. Therefore, the objectives of this study were 1) determine DNA fragmentation induced by apoptosis its relationship with male fertility in spermatozoa from bulls with varying fertility, and 2) identify expression dynamics of Protamine 1 and examine chromatin structure in spermatozoa from bulls with varying fertility. To accomplish our goals we determined 1) the DNA damage, phosphatidylserine (PS) translocation, and expression of pro- and anti-apoptotic proteins (BAX and BCL-2) as well as 2) the expression and localization of Protamine 1 (PRM1) with chromatin condensation and protamination in sperm from bulls with varying fertility. Our results demonstrated that the most relevant fertility markers might be the percentage of necrotic spermatozoa detected by flow cytometry and live spermatozoa determined via eosin-nigrosin staining and that there was no relationship between apoptosis and male fertility. While BCL-2 was not expressed, BAX was identified in bovine spermatozoa. However, the expression of BAX did not differ among groups. In addition, defective chromatin condensation and protamination errors were significantly increased in sperm from low fertility bulls, while the expression of PRM1 was significantly abundant in high fertility bulls. Bull fertility was negatively correlated with protamination errors and defective chromatin condensation, and it was positively correlated with the expression of PRM1. We concluded that defective sperm DNA condensation, not abortive apoptosis, might be the major reason of male infertility in bulls and that sperm chromatin stability differs among bulls with varying fertility. Improper chromatin packaging during spermatogenesis might be caused by the limited expression and/or mislocalization of PRM1. Thus, inadequate chromatin dynamics were associated with bull infertility, which might lead improper fertilization.
224

Effect of selection for fertility of frozen-thawed semen on fertility and spermatozoal motility of fresh and stored non-frozen chicken semen.

Yousif, Yousif Fathalla. January 1982 (has links)
No description available.
225

Identification of Endogenously Biotinylated Proteins in Mammalian Spermatozoa

Das Lala, Meenakshi 27 May 2011 (has links)
No description available.
226

Sodium ion transporters in sperm: Epigenetic regulation of the sperm-specific alpha4 Na,K-ATPase and role of the epithelial sodium channel alpha in sperm physiology

Kumar, Deepti Lava 06 May 2014 (has links)
No description available.
227

Enhancing Saugeye (Sander vitreus x S. canadensis) Production Through the Use of Assisted-Reproduction Technologies

Blawut, Bryan Joseph 24 May 2017 (has links)
No description available.
228

In vitro culture of mouse spermatozoa, oocytes, and early embryos in the presence of intrauterine device /

Paschall, Charles Bayard January 1984 (has links)
No description available.
229

In vitro effects of aqueous extract of aspalathus linearis (rooibos) on human sperm cells

Takalani, Ndivhuho Beauty January 2020 (has links)
Thesis (M. Sc. (Medical Sciences)) -- University of Limpopo, 2020 / This study investigated the effect of rooibos tea on human sperm in vitro. Semen samples from 50 healthy men and 50 patients were treated with aqueous extracts of fermented rooibos (0 µg/ml, 0.10 µg/ml, 1.0 µg/ml, 10 µg/ml, 100 μg/ml) and unfermented rooibos (0 µg/ml, 0.15 µg/ml, 1.5 µg/ml, 15 µg/ml, 150 μg/ml) for one hour at 37ºC. Thereafter, sperm parameters were analysed. Exposure to unfermented rooibos had no effect on sperm motility, vitality and DNA fragmentation in both groups (P>0.05). However, this treatment significantly increased the production of reactive oxygen species, thus influencing the acrosome reaction, and demonstrated a decrease in mitochondrial membrane potential in the donor group (P<0.05). Treatment with fermented rooibos increased progressive motility in the donor group (P<0.05) but had no effect on sperm vitality, reactive oxygen species and the acrosome reaction in either group (P>0.05). A decrease in mitochondrial membrane potential and DNA fragmentation was observed in the donor group and the patient group (P<0.05). Rooibos tea maintains certain sperm functional parameters, and this may positively affect fertility rate. / National Research Foundation (NRF)
230

A study of the functional anatomy of the bovine cervix with special reference to the epithelium, mucus secretion and sperm transport

Mullins, K. June January 1987 (has links)
Anatomical features of bovine cervical epithelium were investigated with respect to mucus secretion and sperm transport. Techniques included: 1. Surface staining of fixed tissue blocks in Harris' hematoxylin followed by steriomicroscopic examination, 2. Model construction from serial sections using both computer-aided and plexiglas assembly of epithelial tracings, 3. Histochemical investigation using five follicular phase animals (four bred naturally 8 to 12-h before slaughter) and three luteal phase animals. Cross-sections of two samples from each quarter cervix were stained with (1) Alcian blue (AB) at pH 1.0 (sulfomucins) and at pH 2.5 (sialomucins and sulfomucins); (2) periodic acid Schiff (PAS) (neutral mucins) and AB (pH 2.5); (4) high iron diamine (HID) (neutral and sulfomucins) with AB (pH 2.5). Additional samples were processed for ultrastructural examination. The mucosa was characterized by longitudinal primary and secondary folds which maintained continuity throughout the cervix, with numerous tertiary shallow ’grooves’ apparent on all epithelial surfaces. No evidence was found suggesting blind-ending glands or crypts. Staining results in follicular animals indicated a predominance of neutral and sulfated mucins in apical areas with secreted mucins extending as sheets from these areas toward the central canal. In basal areas (within grooves) sialomucin production was predominant with secreted mucins evident within grooves and between neutral mucin layers. In luteal phase animals, sulfated and neutral mucins were abundant in both basal and apical areas, while sialomucin production was decreased. Using light and transmission electron microscopy, spermatozoa observed within the cervix appeared unidirectionally opposed to ciliary beat. Suggested privileged paths for the transport of viable spermatozoa are within grooves, where sialomucins were most predominant. / Master of Science / incomplete_metadata

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