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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.
551

Epidemiology of joint injuries in thoroughbred racehorses in training

Reed, Suzanne Rene January 2011 (has links)
No description available.
552

Effects of running on hormonal growth factors

Blostein, Ashley C. January 1993 (has links)
To determine the influence of running on certain blood-born parameters that are involved in bone metabolism, serum levels of calcium, alkaline phosphatase (ALP, a marker of bone formation), growth hormone (hGH), and parathyroid hormone (PTH), were analyzed in 10 male subjects following a 40 min. run at 70% VO2max. Each trial was preceeded by 1 day of inactivity, a 8-12 hr. fast, and drawing of a baseline blood sample by venipuncture. All other blood samples were taken via an indwelling catheter which was inserted in an antecubital vein immediately following the completion of the exercise bout. When the catheter was in place, an "immediate post" sample was drawn. Subsequent samples were taken at 1, 2, 3, 4, 5, 10, 15, 20, 30, 45, and 60 min. after the immediate post sample. Analysis of serum calcium concentrations demonstrated that levels were significantly elevated by 12% following exercise, going from a fasted level of 9.7 ± .53 mg/dl to post-exercise levels of 11.8 ± .73 mg/dl. Serum calcium remained elevated during the first 4 min. following exercise. By 5 min. post-exercise, calcium levels dropped to levels that were significantly lower than the post-exercise sample. However, serum alkaline phosphatase did not change significantly following exercise, as the values remained within normal range throughout the experimental period. Concentrations tended to decrease over time but were not significantly lower than the preor post-exercise levels by the end of the sampling period. Serum concentrations of hGH were more than doubled following a single bout of exercise, going from 4.0 ± 0.98 ng/ml before exercise to 8.8 ± 1.6 ng/ml immediately post-exercise. Following this initial rise, hGH progressively declined and returned to baseline values by 30 min. post-exercise. The concentrations of PTH did not change significantly following exercise. The postexercise sample tended to be higher than baseline values but were not significantly different. The results presented here indicate that an exercise bout 40 min. at 70% V02max results in an elevation of serum calcium and hGH, but does not alter PTH secretion or ALP activity. The data presented in this study indicate that the temporary rise in calcium following exercise is unrelated to PTH. It is hypothesized that the increase in calcium that we observed is attributable to lactate accumulation that would result from an exercise bout of this nature. The buildup of lactic acid and drop in pH causes a dissolution of the crystaline calcium hydroxyapatite compartment of the skeleton, thus causing an increase in ionized calcium. It is not known whether a single bout of exercise can influence hormonal secretion to a sufficient degree to affect bone density, but the hormonal changes demonstrated here could be involved in long-term effects of training. / School of Physical Education
553

The influence of hormone suppression therapy and related factors on bone mineral density in cancer patients

Manning, Katherine L. January 2008 (has links)
Cancer-treatment-induced bone loss (CTBL) is a well-recognized co-morbidity that affects many cancer patients. Commonly used to treat breast and prostate cancer patients, hormone suppression therapy (HST) may accelerate bone loss, resulting in osteopenia or osteoporosis. Because of their broad clinical utility, lifestyle and dietary modifications, such as regular participation in bone-stressing exercise and calcium supplementation, are starting to play a much larger role in the prevention and treatment of CTBL. However, only limited information is available on the effects that these factors may have on bone mineral density (BMD). Purpose. The purpose of this investigation was to assess the degree of BMD change from the onset of HST to 6 months and to examine the impact that physical activity and calcium intake may have on BMD. Methods. Twelve subjects (8 females and 4 males) undergoing HST for breast or prostate cancer were enrolled in the study. BMD at the spine, dual femur, and total body was assessed by dual-energy x-ray absorptiometry at 0 and 6 months. In addition, subjects wore an accelerometer to assess physical activity level and completed a lifestyle questionnaire at baseline, 3, and 6 months after starting therapy. Aside from the 7 non-exercise subjects, 5 subjects chose to participate in The Cancer Exercise Program at Ball Memorial Hospital or complete bone-stressing exercises at home. Results. No significant changes in BMD were observed after 6 months of HST between the groups at any of the sites. When all subjects were examined together, a significant BMD decrease of 3.2% was observed at the lumbar spine. The accelerometer and lifestyle questionnaires revealed that the males were more active than the females and the exercisers were more active than the non-exercisers at both baseline and after 6 months of HST. Supplementation with calcium did not affect BMD changes at any site;although it is possible this is an effect of gender as all males were included in the same group. Lifestyle factors such as history of smoking and alcoholism were also examined, but were not correlated to changes in BMD. Conclusion. Treatment with HST results in decreases in BMD, particularly at the spine. Bone-stressing exercise helped maintain or improve total body BMD in 3 of the 5 subjects the exercise group. There appears to be no difference in BMD between those who supplemented with calcium and those who did not. / School of Physical Education, Sport, and Exercise Science
554

Postnatal vitamin D supplementation normalizes neonatal bone mass following maternal dietary vitamin D deficiency in the guinea pig

Finch, Sarah L. January 2007 (has links)
Since vitamin D deficiency is common at birth, the objective of this study was to test if postnatal vitamin D supplementation would normalize bone mineralization. Forty guinea pigs were randomized to receive a diet with or without vitamin D3 during pregnancy. Newborn pups were randomized to receive 10 IU of vitamin D3 or a placebo daily until d28. Measurements at birth and d28 included whole body and regional bone mass, osteocalcin and deoxypyridinoline, plus biomechanical testing of excised tibias and femurs. Offspring from deficient sows had lower body weight, whole body and tibia bone mineral content (BMC) and lower osteocalcin and biomechanical integrity. By d28 this group had lower whole body bone density and femur BMC, unless supplemented. Interactions with gender showed males continued to have low 25(OH)D despite supplementation. Therefore, neonates born to sows with dietary vitamin D deficiency require supplemental vitamin D to support normal bone mineral accretion.
555

Relationship between total, axial and peripheral bone mineral density, lifetime milk consumption and lifetime physical activity in elderly mothers and their premenopausal daughters

Ulrich, Cornelia M. 09 December 1992 (has links)
Graduation date: 1993
556

Suppression of osteoblast activity by disuse is prevented by low magnitude mechanical loading through a bone morphogenic protein-dependent Mechanism

Patel, Mamta Jashvantlal 15 January 2008 (has links)
Musculoskeletal pathologies associated with decreased bone mass, including osteoporosis and disuse-induced bone loss, affect millions of Americans annually. Many pharmaceutical treatments have slowed osteoporosis, but there is still no countermeasure for bone loss observed in astronauts. Additionally, high magnitude and low frequency impact has been recognized to increase bone and muscle mass under normal but not microgravity conditions. However, a low magnitude and high frequency (LMHF) mechanical load experienced in activities such as postural control has also been shown to be anabolic to bone. While several clinical trials have demonstrated that the LMHF mechanical loading normalizes bone loss in vivo, the target tissues and cells of the mechanical load and underlying mechanisms mediating the responses are unknown. As such, the objectives of this project are to analyze cellular and molecular changes induced in osteoblasts by LMHF loading and to investigate the utility of a LMHF mechanical load in mitigating microgravity-induced bone loss. The central hypothesis of the project is that simulated microgravity or disuse conditions induce bone loss by inhibiting expression of genes critical in regulating bone formation, osteoblast differentiation, and subsequent mineralization while a LMHF mechanical load prevents these effects. To test this hypothesis, we developed an in vitro disuse system using the Random Positioning Machine (RPM). For the first time, we reported systemic gene expression studies in 2T3 preosteoblasts using the RPM disuse system showing that 140 genes were altered by RPM exposure with over two-fold statistically significant changes. Moreover, we also utilized an independent simulator called the Rotating Wall Vessel (RWV) to partially validate the in vitro disuse systems and to confine the list of genes to those most critical in regulating bone formation. After comparative studies, we constricted the list to 15 commonly changed genes, three of which were not only decreased with disuse but also increased with mechanical loading in vivo. Furthermore, we employed the RPM disuse system to evaluate the mechanism by which a LMHF load mitigates bone loss. Exposure of osteoblasts to the RPM decreased both ALP activity and mineralization even in the presence of bone morphogenic protein 4 (BMP4), and the LMHF mechanical loading prevented the RPM-induced decrease in both markers. Mineralization induced by LMHF mechanical loading was enhanced by treatment with BMP4 and blocked by the BMP antagonist noggin, suggesting a role for BMPs in this response. In addition, LMHF mechanical loading rescued the RPM-induced decrease in gene expression of ALP, runx2, osteomodulin, parathyroid hormone receptor 1, and osteoglycin. These findings show that osteoblasts directly respond to LMHF mechanical loading, potentially leading to normalization or prevention of bone loss caused by disuse or microgravity conditions. The mechanosensitive genes identified here provide potential targets for pharmaceutical treatments that may be used in combination with LMHF mechanical loading to better treat osteoporosis, disuse-induced bone loss, or microgravity-induced bone loss.
557

Osteodistrofia de la cirrosis biliar primaria

Guañabens Gay, Nuria 17 December 1987 (has links)
La cirrosis biliar primaria es una enfermedad hepática que se manifiesta por un patrón clínico, bioquímico e histológico de colestasis crónica. Su curso puede complicarse con el desarrollo de una patología metabólica ósea cuyo tipo, frecuencia y mecanismos patogenéticos no están bien establecidos. Esta tesis se ha realizado con el fin de analizar la prevalencia y tipo de enfermedad metabólica ósea que se asocia a la cirrosis biliar primaria (CBP) e investigar los factores que influyen en su desarrollo. 1) PACIENTES Y MÉTODOS Se han estudiado 20 pacientes con CBP (18M, 2 V) con una edad media de 48.6 +/- 10.6 años. A todos ellos se ha practicado: estudio del grado de colestasis biológica y de la función hepatocelular, además de determinaciones bioquímicas y hormonales (25-hidroxivitamina D; 1,25 dihidroxivitamina D y parathormona N-terminal) del metabolismo mineral. En 16 pacientes se determinó la capacidad de absorción intestinal de calcio. A todos los pacientes se practicaron radiografías de la columna vertebral y biopsia ósea, por vía transilíaca, tras doble "marcaje" con tetraciclinas, para análisis histomorfométrico en especimen óseo no decalcificado. El estudio histomorfométrico se realizó mediante el método semiautomático y se analizaron parámetros estáticos y dinámicos. 2) RESULTADOS Siete pacientes tenían una osteoporosis al presentar una reducción del volumen trabecular. Tres de ellos tenían asociado un trastorno moderado de la mineralización ósea que no cumplía criterios de osteomalacia. Quince pacientes (5 con osteoporosis) tenían una disminución del grado de formación ósea y en 19 casos la reabsorción ósea era normal o estaba disminuida. Los pacientes con osteoporosis tenían una duración de la CBP más prolongada (5.4 +/- 2.8) que los pacientes sin osteoporosis (2.0 +/- 2.1 a p= 0.07). Además, la osteoporosis fue significativamente más frecuente en las mujeres postmenopáusicas, ya que 6 de los 7 pacientes con osteoporosis (86%) pero sólo 3 de los 11 sin osteoporosis (27%) eran mujeres postmenopaúsicas (p= 0.02). Por otro lado, los pacientes con osteoporosis tenían con mayor frecuencia una malabsorción intestinal de calcio (80%) que los pacientes sin osteoporosis (18%) (p= 0.03). Aunque la severidad de la colestasis no se relacionó con la presencia de osteoporosis, sí se halló una relación lineal inversa entre la absorción intestinal de calcio y la concentración plasmática de sales biliares (r= -0.55, p < 0.05) y el nivel sérico de la fosfatasa alcalina (r= -0.5, p < 0.05). Cuatro pacientes, dos de ellos con trastornos de la mineralización ósea, tenían niveles séricos bajos de 25-hidroxivitamina D. Sin embargo, los niveles séricos del metabolitos 1,25-dihidroxivitamina D fueron normales en todos los casos. 3) CONCLUSIONES Los resultados de este estudio indican que: 1.- La osteoporosis es la enfermedad metabólica ósea que comúnmente se asocia a la cirrosis biliar primaria. Su prevalencia fue del 35% en nuestra serie analizada. 2.- Los pacientes con cirrosis biliar primaria de nuestro medio no desarrollan una osteomalacia, aunque no es infrecuente que presenten un trastorno moderado de la mineralización ósea. Un 15% de los pacientes desarrollaron este trastorno. 3.- La osteoporosis asociada a la cirrosis biliar primaria es de bajo "turnover" óseo y su base fisiopatológica es un déficit de la formación ósea. El 71% de los pacientes con osteoporosis tenían un déficit de la formación ósea, alteración que también presentaba el 83% de los pacientes sin osteoporosis. Ello permite sugerir que un elevado porcentaje de pacientes con cirrosis biliar primaria y masa ósea normal están en alto riesgo de desarrollar una osteoporosis. 4,- Los factores de riesgo implicados en el desarrollo de osteoporosis en la cirrosis biliar primaria son: duración de la hepatopatía, estado postmenopáusico y malabsorción intestinal de calcio. 5,- El desarrollo de un trastorno moderado de la mineralización ósea es más frecuente en los pacientes con déficit de 2S-hidroxivitamina D. Sin embargo, el "status" deficitario de vitamina D no es exclusivo de los pacientes con trastorno de la mineralización ósea.
558

Den uppklädda människan : en diskussion kring den gropkeramiska klädesstilen / The dressed human : a discussion regarding the Pitted Ware clothing

Orascanin, Nikola January 2010 (has links)
This thesis discusses the dress code during the Pitted Ware culture on the Swedish island of Gotland. Eight Pitted Ware grave-fields have been analyzed; only 74 skeletons have been identified with some sort of ornament that could have been attached to clothes. The grave-fields are rich in finds and in people nearly every age group is present. The analysis has shown that there are clear differences between the genders. The female always has some sort of seal tooth ornament around her waist and thighs. The man has sometimes tusks from wild boar and tubular bones as an ornament on his clothes. The children have all of the ornaments that the parents have but in smaller numbers. There are also other finds that appear on all of the individuals, but the tusks, seal tooth and tubular bones are the ones that appear on nearly every individual. The North American Indians clothing has been used as a reference to help understand the clothing of the Pitted Ware. So far all of the finds that have been found on the skeletons have shown great diversity in the Pitted Ware clothing.
559

Automatic segmentation and analysis of Magnetic Resonance images of the knee bones and cartilages

Mr Jurgen Fripp Unknown Date (has links)
No description available.
560

A pilot study to develop and validate a traditional Chinese medicine (TCM) questionnaire: a health status instrument for TCM assessment in patients with Osteoarthritis (OA) of the hip or knee

Wang, Ping Unknown Date (has links)
Research suggests acupuncture is potentially an effective treatment for osteoarthritis (OA) of the hip or knee. Essential for the evaluation of Chinese acupuncture treatment is the availability of a reliable and valid measurement. However, currently there is no appropriate measurement instrument validated within traditional Chinese medicine (TCM) concepts and frameworks. Objective is to develop and validate a TCM questionnaire as a health status instrument for TCM assessment in patients with OA of the hip and knee. Methods The TCM questionnaire was developed from TCM theory and clinical experience. The questionnaire was examined by experts, for content and faces validity and pre-tested on a volunteer sample of three subjects. The developed questionnaire was validated on a convenience sample of ten subjects from six different clinical settings in Auckland region. The practitioner or receptionist from the selected clinical sites handed out the questionnaire package to their patients who fulfilled the study criteria. Each patient (subject) completed the questionnaire on their arrival and the re-testing questionnaire at a two-week interval. The reliability of the questionnaire was estimated by examining the internal consistency reliability (Cronbach's alpha statistic) and test-retest reliability (Intra-class correlation coefficients). The content validity of the questionnaire was examined by literature review, interviews with patients, and experts' judgement. The construct validity was estimated by the methods of known groups, correlations between scales, and correlations with the SF-36 health survey. The success of the grouping or scaling of the questionnaire was estimated by examining the item (i.e. question) internal consistency and item (i.e. question) discriminant validity. Results The TCM questionnaire scales corresponded to the "eight principal syndromes", "ten questions", and "eight patterns of OA" within TCM concepts and frameworks. Internal consistency reliability (Cronbach's alpha) was above .70 for all scales on both occasions of the first test and the second test. Test-retest reliability (intra-class correlation coefficient) for each scale was also above .70 for all scales, except the exterior (EXT) scale, which was .44. Moderate associations were found between the age of subjects and the scores of the interior (INT) scale and summary (SUM) scale. There was a significant difference between the groups of use and non-use of on-going medication in the EXT scale scores on the first test, p = .012. However, this significant difference was not found on the second test. As expected, strong or moderate associations were found between the TCM questionnaire and SF-36 comparable scales. Conclusions The TCM questionnaire was developed within TCM concepts and frameworks. The questionnaire contains 23 items with two main scales (the EXT scale and the INT scale) and one additional scale (the SUM scale). It takes approximately five minutes to complete and is entirely self-administered. Results from this pilot study indicate that this TCM questionnaire might have adequate reliability and validity. Therefore, the questionnaire has potential usage as an outcome measurement instrument for the assessment of TCM in the patients with OA of the hip or knee. For this application to be possible, the questionnaire needs further development and validation with a larger sample of patients who have a variety of OA conditions.

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