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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 shell of the whelk Buccinum undatum L shape analysis and sex discrimination /

Hallers-Tjabbes, Catharina Carolina ten. January 1979 (has links)
Thesis--Groningen. / Summary in English and Dutch. "Stellingen" inserted. Bibliography: p. 120-129.
32

Obstetrical implications of sexual dimorphism in hominoid os coxae

Costa, Stephanie 08 April 2016 (has links)
Many studies have examined pelvic sexual dimorphism and its functional implications in linear analyses, but few have used three-dimensional (3D) methods, which are ideal for complex structures such as the pelvis. This study examines human and ape os coxae using 3D geometric morphometrics (GM) to determine if patterns of sexual dimorphism relate to obstetrical and/or biomechanical requirements. Twenty-five 3D landmarks were collected on 35 human and 116 hominoid os coxae. Generalized Procrustes and principal component analyses were performed on combined and sex-specific species samples. Tests of male and female human os coxae demonstrate dimorphism in several pelvic traits related to increasing birth canal dimensions in females; females have a wider subpubic angle and greater sciatic notch than males, as well as a short ischial spine. Hominoids, however, did not exhibit sexual dimorphism in pelvic shape. These results confirm previous studies showing that human pelvic shape dimorphism is related to the obstetrical requirements of birthing a large fetus, rather than sexual dimorphism in locomotor biomechanics. Future 3D GM research on other primate species that have large neonates relative to maternal size may determine whether the primate pelvis exhibits similar patterns of response to obstetrical selection pressures as in humans.
33

Influencia do sexo e dos hormonios sexuais na inflamação induzida pela administração de formalina na articulação teporomandibular de ratos / Effect of sex and sex hormones on formalin-induced temporomandibular joint inflammation

Torres Chavez, Karla Elena, 1978- 29 February 2008 (has links)
Orientador: Claudia Herrera Tambeli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-11T04:28:22Z (GMT). No. of bitstreams: 1 TorresChavez_KarlaElena_M.pdf: 670310 bytes, checksum: c227fd036c2b7fc05c311f21f575f1b2 (MD5) Previous issue date: 2008 / Resumo: A alta prevalência das condições dolorosas e desordens inflamatórias da articulação temporomandibular e de doenças inflamatórias no sexo feminino sugere a participação dos hormônios sexuais na modulação da dor e da resposta inflamatória da articulação temporomandibular. Estudos prévios sugerem que os altos níveis do estradiol durante o ciclo estral e a administração de estradiol ou progesterona em ratas ovariectomizadas ou testosterona em ratos orquidectomizados diminui a nocicepção induzida pela injeção de formalina (1,5%) na articulação temporomandibular. O mecanismo pelo qual esses hormônios reduzem a nocicepção da articulação temporomandibular ainda não é conhecido, mas poderia ser delimitado por uma atividade antiinflamatória. Diante disso, o objetivo deste trabalho foi avaliar o efeito do sexo e dos hormônios sexuais na inflamação induzida pela injeção de formalina na articulação temporomandibular. Para avaliar a inflamação na articulação temporomandibular, nós mensuramos o extravasamento plasmático e a migração de leucócitos polimorfonucleares (neutrófilos). A formalina, agente nociceptivo e inflamatório, induziu extravasamento plasmático e migração de neutrófilos significativamente menor em fêmeas em proestro que em fêmeas em diestro e machos. O extravasamento plasmático e a migração leucocitária em fêmeas ovariectomizadas foi similar ao de fêmeas sham-ovariectomizadas em diestro e significativamente maior que o de fêmeas sham-ovariectomizadas em proestro. A administração de estradiol, mas não de progesterona em fêmeas ovariectomizadas diminuiu significativamente o extravasamento plasmático e a migração leucocitária induzida pela injeção de formalina na articulação temporomandibular. A orquidectomia não afetou o extravasamento plasmático e a migração leucocitária, no entanto, administração de testosterona em machos orquidectomizados os reduziu significativamente. Dessa forma, pode-se concluir que o estradiol e a testosterona exercem um pronunciado efeito antiinflamatório na articulação temporomandibular, sugerindo que este efeito pode mediar, ao menos em parte, o efeito antinociceptivo destes hormônios na articulação temporomandibular / Abstract: The greater prevalence of pain conditions in temporomandibular joint and inflammatory diseases in female suggests the involvement of sex hormones in temporomandibular joint pain and inflammation. Previous studies suggest that the high estradiol level during the rat estrous cycle and the administration of estradiol or progesterone in ovariectomized female or testosterone in orchiectomized male rats decrease formalin-induced temporomandibular joint nociception. The mechanism by which sex hormones decrease temporomandibular joint nociception is unknown, however could be mediated by decreasing temporomandibular joint inflammation. For that reason, the aim of this study was to evaluate the effect of sex and sex hormones on formalin-induced temporomandibular joint inflammation. To measure temporomandibular joint inflammation, we evaluated plasma extravasation and neutrophil migration. Formalin induced significant lower temporomandibular joint plasma extravasation and neutrophil migration in proestrus females than in males and in diestrus females. Formalin-induced temporomandibular joint plasma extravasation and neutrophil migration in ovariectomized females were similar to those of sham-operated diestrus females and significantly higher than those of sham-operated proestrus females. Estradiol but not progesterone administration in ovariectomized females significantly reduced formalin-induced temporomandibular joint plasma extravasation and neutrophil migration. Formalin-induced temporomandibular joint plasma extravasation and neutrophil migration were not affected by orchiectomy, while testosterone administration in orchiectomized males significantly decreased them. Taken together, these findings demonstrate a pronounced anti-inflammatory effect of estradiol and testosterone in temporomandibular joint and suggest that this effect may mediate, at least in part, the antinociceptive effect of these hormones on the temporomandibular joint / Mestrado / Fisiologia Oral / Mestre em Odontologia
34

Sex determination by measuring the maximum width of maxillary incisors, canines and mandibular canines in a sample of young South African adults

Claassens, L. January 2016 (has links)
>Magister Scientiae - MSc / Sex determination of human remains is often a dilemma for forensic experts due to the decomposing factor, or, if only part of a body is found. The analysis of DNA is thought to be the most accurate method for sex determination, but the cost and time involvement usually causes a delay in the identification process and in some cases, DNA is not obtainable due to the state of decomposition or contamination. Sexual dimorphism refers to the difference in shape, form or appearance between male and females in the same species. It can also be described as the systematic difference between individuals of different sex in the same species. Dimorphism in the human skeletal system and dentition is well establish. It is generally assumed that the male dentition is larger than the female dentition. In this study, the mesio-distal width of the maxillary incisors and canines, as well as the mandibular canines were measured. Orthodontic study models were used in this study, 50 males and 50 females, in which the sizes of the maxillary central incisors, maxillary lateral incisors, and maxillary and mandibular canines were measured. The results showed that the sizes of the maxillary and the mandibular canines were significantly more accurate in determining sexual dimorphism than the incisors. The logistic regression model, using tooth 13 and 33, provides prediction accuracy of 52% for males and 74% for females.
35

The Impacts of Sex and Myogenic Cell Transplantation on Collateral Capillary Arteriogenesis

Sivesind, Padon Mary 01 March 2018 (has links)
Current treatments for peripheral arterial occlusive disease (PAOD) have limited success, so there is a need to develop more effective treatments. Because patients with native collaterals have a better prognosis, promoting collateral arteriogenesis is a potential PAOD treatment. Additionally, female PAOD patients have a worse response to treatment and a worse prognosis compared to males, which could be due to impaired collateralization. Cell transplantation is a potential treatment option to promote collateral arteriogenesis. Bone marrow derived stem cells are the main cell type that has been investigated, but they have had limited clinical success. Delivering a stem cell type native to the tissue like myogenic stem cells could have improved outcomes. In this study, the lateral spinotrapezius feed artery was ligated in male and female Balb/C mice to induce collateral capillary arteriogenesis, and 7 days post ligation ­­­­arterialized collateral capillary (ACC) number and diameter were determined. There were no differences between sexes, which could be because young, healthy mice were used in this study rather than aged and diseased models. Because we observed no sex differences, we then assessed the effect of myogenic cell transplantation in male mice only. Immediately following ligation of the spinotrapezius feed artery, mice were treated with myogenic cells, thrombin, or vehicle, and 7 days post ligation ACC number and diameter were determined. Thrombin increased ACC number, but myogenic cells had no effect. However, myogenic cells increased ACC diameter, and both myogenic cells and thrombin decreased ACC number in the region of the muscle with the largest collateral, and increased the maximum ACC diameter. Another factor that could affect ACC formation is a pre-existing collateral (PEC), which only some Balb/C mice have, so we also separated mice into PEC and non-PEC groups for analysis. In mice with a PEC, thrombin increased ACC number, and both myogenic cells and thrombin increased ACC diameter. There was a trend toward smaller arterialized capillaries in mice with a PEC, which could be because the majority of the blood flow is redirected through the PEC, so the PEC was the main vessel to remodel. These results are consistent with previous studies that indicated that thrombin augments arteriogenesis as well as increasing V-CAM, and suggest that myogenic cells have a similar effect possibly by secreting arteriogenic factors such as VEGF and MMPs. Because myogenic cells increase arteriogenesis, and macrophages are an essential regulator of arteriogenesis, we also tested the hypothesis that myogenic cells would increase macrophage content. Macrophage number increased with ligation, but there was no difference in macrophage number between any of the treatment groups. The lack of difference in macrophage number could be because the day 7 timepoint was too late, as macrophage content peaks at day 3. Because myoblasts increased arteriogenesis, they also may have increased the number M2 macrophages, which are the main macrophage contributor to arteriogenesis, but we used a general macrophage marker and could not detect an increase in M2 macrophages. In future studies, to determine if there is an increase in M2 macrophages a stain specific to M2 macrophages like CD206 could be added. Additionally, a diabetic Balb/C strain could be used to determine if arteriogenesis is impaired in males compared to females in a diseased model.
36

Sex estimation using the diagonal diameter measurements of first mandibular molars in a Sudanese sample

Phillips, Vincent January 2020 (has links)
Magister Scientiae Dentium - MSc(Dent) / Sexual identification of immature skeletal remains is still a complicated issue to solve in Forensic Anthropology. Sexual dimorphism is the condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs. (1) The aim of this study is to evaluate the existence of sexual dimorphism in mandibular first molars. The base sample of the study includes 300 Sudanese (150 males and 150 females). Their ages ranged from 17 to 55. The mesio-buccal (MB) disto-lingual (DL) and the mesio-lingual (ML) disto-buccal (DB) surfaces of the mandibular first molars were measured using a digital Vernier caliper on plaster of Paris study casts. The data was analyzed using the t-test. The results showed statistically significant sexual dimorphisms in male and female odontometric features. The mean values of the parameters were greater in males than in females in both (MBDL and MLDB) with greater sexual dimorphism in the MBDL (MBDL dimorphism =28.672 %) than the MLDB (MLDB dimorphism =21.596 %). Conclusion: Sexual dimorphism of 1st molar teeth can aid in the identification of skeletal remains of Sudanese origin.
37

The evolution of alternative morphologies : an empirical investigation in the wing dimorphic cricket, Gryllus firmus

Crnokrak, Peter. January 1998 (has links)
No description available.
38

Sexual dimorphism in prolactin secretory patterns and their regulation by estradiol in adult sheep

Paquette, Julie January 1993 (has links)
No description available.
39

Sexual Dimorphisms in the Brain: Neural Substrates for Cognitive and Clinical Differences

Henry, Jensen K. 24 April 2010 (has links)
No description available.
40

Sex-Based Differences in Calcaneal Injury Tolerances Under High-Rate Loading

Ceritano, Davide Walter 24 June 2020 (has links)
In this experiment, average calcaneal fracture force is measured across male and female groups. The purpose of this experiment is an analysis of alternatives exploring the importance of sex-based criteria in models representing injuries typical in underbody blast environments. Seventeen (17) right legs were harvested at the knee from cadavers representing three anthropometries: 50th percentile male (6), 75th percentile female (6), and 5th percentile female (5). Care was taken to preserve anatomically correct geometry as the legs were cut to equal lengths, the tibia and fibula were potted in Dyna-Cast®, flesh and ligaments were excised from the inferior surface of the calcaneus, and a small Dyna-Cast® pad was poured and sanded flat – interfacing with the exposed calcaneal surface. Each test specimen was mounted in a custom fixture and exposed once to high-rate axial loading characterized by a constant acceleration and 25.4mm intrusion, achieving an average speed of 4.7m/s (σ = 0.3m/s) in 10ms. Input acceleration was measured by an Endevco 7264c accelerometer and a Denton 2513 six-axis load cell measured reaction force proximal to the specimen. A VR Phantom v9.1 camera recorded x-ray imagery at 2k frames per second. Data were collected by a TDAS Pro data acquisition system at 20k samples per second and filtered in accordance with SAE J211. Time of fracture, established through x-ray imagery, was used to determined fracture force from the electronically synchronized load-cell data. 100% injury was recorded. Average calcaneus fracture forces were reported as follows: 5406N (σ = 780N) for 50th percentile males, 4130N (σ = 1061N) for 75th percentile females, and 2873N (σ = 1293N) for 5th percentile females. Statistical significance was established between the reported averages according to three ANOVA tests: One-way (p = 0.0054), Brown-Forsythe (p = 0.0091), and Welch's (p = 0.0156). Unpaired Student's t-test confirmed significant differences between 50th percentile male vs 75th percentile female (p = 0.0469) and 50th percentile male vs 5th percentile female (p = 0.0030); the t-test did not show significance between the two female groups (p = 0.1315). Average impulse-to-fracture was calculated for each group and found to be not statistically significant. / Master of Science / A marked shift can be found in combat wound epidemiology towards a predominance of extremity injuries sustained from explosives. The Warrior Injury Assessment Mannequin (WIAMan) Project sought to develop a baseline dataset of post-mortem human surrogate responses to realistic explosive loading and correlate it to a highly instrumented mannequin for the further development of combat vehicles and personal protective gear. The following experiment exists within the WIAMan paradigm as an analysis of alternatives exploring the adequacy of the above mentioned baseline dataset in directly representing both male and female injuries. More specifically, this experiment interrogates the differences in average fracture forces between male and female calcanei across three anthropometries: 50th percentile male, 75th percentile female, and 5th percentile female. Testing was carried out on 17 right cadaver legs cut to equal lengths, potted proximally in Dyna-Cast®, with the inferior surface of their calcanei exposed; a small Dyna-Cast® pad was poured for each calcaneus and sanded flat. Each test specimen was fixed to a Denton 2513 six-axis load cell proximally and exposed to a high-rate, constant acceleration, 25.4mm displacement aligned with the calcaneus along the long axis of the leg bones. Fracture time, established through x-ray images recorded at 2k frames per second with a VR Phantom V9.1 camera, was used to determine load cell force measurement at fracture. Average calcaneus fracture forces were reported as follows: 5406N (σ = 780N) for 50th percentile males, 4130N (σ = 1061N) for 75th percentile females, and 2873N (σ = 1293N) for 5th percentile females. Statistical significance was established between the reported averages according to three ANOVA tests: One-way (p = 0.0054), Brown-Forsythe (p = 0.0091), and Welch's (p = 0.0156). Unpaired Student's t-test confirmed significant differences between 50th percentile male vs 75th percentile female (p = 0.0469) and 50th percentile male vs 5th percentile female (p = 0.0030); the t-test did not show significance between the two female groups (p = 0.1315). Average impulse-to-fracture was calculated for each group and found to be not statistically significant.

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