• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 87
  • 78
  • 11
  • 7
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 249
  • 29
  • 29
  • 24
  • 22
  • 22
  • 20
  • 20
  • 20
  • 18
  • 18
  • 16
  • 15
  • 14
  • 14
  • 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.
41

Definition of topographic organization of skull profile In normal population and its implication on the role of sutures in skull morphology

Pirouzmand, Farhad 02 January 2007
Objectives<p>The geometric configuration of skull is complex and unique to each individual. The main objectives of this study are two fold: 1) to provide a new technique to define the outline of skull profile and 2) to find the common factors defining the ultimate skull configuration in adult population. The secondary objective was to explore the effect of age and sex on skull shape formation.<p>Materials & Methods <p>Ninety-three lateral skull x-ray from the CT scan films were selected and digitized. The lateral skull surface was divided into 3 regions based on the presumed location of coronal and lambdoid sutures. A software program (Canvas 7) was used to match the outer surface of lateral skull with circular curves. Three main curvatures (frontal, parietal, occipital) were consistently identified to overlap the skull periphery. The radius, cord length and inclination of each curvature were measured.. Factor analysis technique was also used to reduce the number of variables explaining the overall shape of skull. Student t-test and regression analysis was also used to explore the effect of sex and age on skull shape. <p>Results <p>There were total of 93 patients in this study (54% male). The average values for three defined curvatures of the skull profile were recorded. Factor analysis produced 3 factors. The first factor explained 32% of total variance and was related to the overall size of the head as represented by total length and the radius of the curvature in vertex and back of the head. The second factor covered 26% of the variance representing the inverse correlation between the angle of the frontal and parietal curves. The third factor revealed the direct correlation of occipital and parietal angle. In all of these factors, the frontal zone variation was independent or opposite of the parieto-occipital zone. A strong direct association between the total length of skull, occipital curve radius and length with the sex was shown. No age related variable was identified.<p>Conclusions <p>There is a large variation in the values of different part of the skull. The skull profile topography can be defined mathematically by two distinct territories: frontal and parieto-occipital zones. These territories hinge on the coronal suture. Therefore, coronal suture may play a dominant role in final skull configuration.
42

Definition of topographic organization of skull profile In normal population and its implication on the role of sutures in skull morphology

Pirouzmand, Farhad 02 January 2007 (has links)
Objectives<p>The geometric configuration of skull is complex and unique to each individual. The main objectives of this study are two fold: 1) to provide a new technique to define the outline of skull profile and 2) to find the common factors defining the ultimate skull configuration in adult population. The secondary objective was to explore the effect of age and sex on skull shape formation.<p>Materials & Methods <p>Ninety-three lateral skull x-ray from the CT scan films were selected and digitized. The lateral skull surface was divided into 3 regions based on the presumed location of coronal and lambdoid sutures. A software program (Canvas 7) was used to match the outer surface of lateral skull with circular curves. Three main curvatures (frontal, parietal, occipital) were consistently identified to overlap the skull periphery. The radius, cord length and inclination of each curvature were measured.. Factor analysis technique was also used to reduce the number of variables explaining the overall shape of skull. Student t-test and regression analysis was also used to explore the effect of sex and age on skull shape. <p>Results <p>There were total of 93 patients in this study (54% male). The average values for three defined curvatures of the skull profile were recorded. Factor analysis produced 3 factors. The first factor explained 32% of total variance and was related to the overall size of the head as represented by total length and the radius of the curvature in vertex and back of the head. The second factor covered 26% of the variance representing the inverse correlation between the angle of the frontal and parietal curves. The third factor revealed the direct correlation of occipital and parietal angle. In all of these factors, the frontal zone variation was independent or opposite of the parieto-occipital zone. A strong direct association between the total length of skull, occipital curve radius and length with the sex was shown. No age related variable was identified.<p>Conclusions <p>There is a large variation in the values of different part of the skull. The skull profile topography can be defined mathematically by two distinct territories: frontal and parieto-occipital zones. These territories hinge on the coronal suture. Therefore, coronal suture may play a dominant role in final skull configuration.
43

Characterizations of Biomechanical Properties of Bones in Mammals

Wu, Yii-der 17 January 2007 (has links)
Pigs, mice and human beings are all vertebrate mammals. More than 90% of genomes in pigs and mice are the same as human beings. Experiment pigs and mice are with advantages in purebloods, small size, high reproductive capacity and short life cycle, etc. The tissue structure and metabolism of physiology in pig and mice are similar to human as well. Therefore, laboratory pigs and mice are often used to substitute human beings for biomedical engineering test. The research topics of this thesis are in the area of biomechanical properties of bones in mammal. The objectives of the study are to reveal the biomechanical properties of various types of bones and discuss its implication to human development. The entire thesis is divided into three parts. The first topic used micro-indentation test and FEM analysis for the determination of biomechanical properties of controlled cartilages in pigs. The second topic applied (a) three-point-bend failure test to study the age-related radius strength in mice, (b) tensile test to study the mechanical response of cranial sutures in mice, and (c) optical interferometry for 3D profile determination of mouse cranium. The third topic is for quantitative analysis of patterns in cranial sutures using DFT (Discrete Fourier Transform). The mechanism of diseases (such as osteoporosis, craniosynostosis, etc.) and the complexity of patterns in human cranial sutures in different age groups are discussed.
44

Phylogeny and Biogeography of the Genus Capricornis (Artiodactyla: Bovidae) Based on Mitochondrial DNA Sequences and Cranial Morphometrics

Chang, Hsun-Cheng 27 June 2002 (has links)
The genus Capricornis Ogilby, 1837, is divided into three species and widely distributed in sourthern China, Tibet, Myanmar, IndoChinese peninsula, Malaysia peninsula, Sumatra, Japanese archipelagos and Taiwan. Using complete cytochrome b sequences (1140 bp) analyzes the genetic variation and phylogeny of genus Capricornis from Taiwan, Japan and Mainland China. Constructed by both distance and maximum parsimony methods, the phyloenetic tree distinguish the Capricornis to three clades: Formosan serow, Japanese serow, and Sumatran serow from mainland China. Formosan serow is more familiar with Sumatran serow than Japanese serow. Local populations of Formosan serow of Taiwan island and Japanese serow of the Japanese archipelagos are already differentiated. Serow and goral are apparently distinguishable. The results of Principal Component Analysis and Discriminant Analysis show that serows from Taiwan, Japan and mainland China and goral are apparently distinguishable at morphological characters. The variation of morphological analysis may be a good tool to identify serow and goral. From the paleogeology and fossil records of serow of Quaternary, we could infer that ancestors of serow from southwestern mountain of mainland China migrated to Taiwan island and Japanese archipelagos through the land bridge of east Asian islands to mainland China in the early Pleistocene caused by the glaciation of Quaternary, then separated from mainland of east Asia and speciation of serow occured in Taiwan island and Japanese archipelagos after the end of the glaciation of Quaternary.
45

Part I¡GCharacterization of humoral immune responses of mice infected with Angiostrongylus cantonensis Part II¡GAnalysis on the cranial morphology of mice infected with Angiostrongylus cantonensis

Yang, Zhi-Ya 10 September 2002 (has links)
Abstract -1 The immune response occurred in the mice infected with Angiostrongylus cantonensis was mainly humoral immune response. This study was designed to compare the systemic and localized humoral immune responses occurred after primary and secondary infections in C57BL/6J mice. Eight weeks after the primary infection with 20 third-stage larvae, each mouse received a second inoculation of the same dosage. Specific serum IgM, IgG and IgE were found in the second week after primary infection. However, the titers of IgG1 and IgG2b increased at the fourth week after primary infection. Antibodies of these mentioned increased continuously as the progress of infection. On the other hand, the IgM and IgG1 titers increased in brain tissue infusion since the forth week after primary infection, while the titer of IgG start to elevate at the sixth week. Nevertheless, the increase of IgG2B was only noticed at the sixth week and no significant change was observed for IgG2a and IgE. After the secondary infection, serum IgM titers increased while the titer of IgG1 in the brain tissue infusion decreased. Results of Western blot showed that IgG1and IgE in the brain tissue infusion lost the ability to recognize a 42 kDa molecule of the somatic and excreting-secreting antigens of fifth-stage larvae. These variations could be used in the diagnosis of the early stage of mice that re-infected with Angiostrongylus cantonensis. Abstract -2 The radiographic lateral views of the skulls of the mice infected with Angiostrongylus cantonensis were taken. Thus, the parietofrontal index ( PI ) was obtained by measuring and calculating the distances among specific positions on their skulls. Compared with the controls, a significant elevation over the top of the crania of the cases was observed sixty days post-infection. In addition, the phenomenon emerged apparently during the second to the fourth week post-infection. These findings are able to be applied as the external diagnostic references for the infection course of mice infected with Angiostrongylus cantonensis.
46

Structure and growth of facial sutures histologic, microangiographic and autoradiographic studies in rats and a histologic study in man /

Persson, Maurits. January 1973 (has links)
Thesis--University of Goteborg, 1973. / Includes bibliographical references (p. 137-146).
47

Masticatory strain and bone growth of two osteogenic surfaces : cranial sutures and the mandibular osteodistraction site /

Sun, Zongyang. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 184-204).
48

Structure and growth of facial sutures histologic, microangiographic and autoradiographic studies in rats and a histologic study in man /

Persson, Maurits. January 1973 (has links)
Thesis--University of Goteborg, 1973. / Includes bibliographical references (p. 137-146).
49

Effects of paired-pulse electrical stimulation of the chorda tympani nerve on cells in the nucleus of the solitary tract of the rat

Rosen, Andrew M. January 2008 (has links)
Thesis (M.S.)--State University of New York at Binghamton, Department of Psychology, 2008. / Includes bibliographical references.
50

An examination of motor speech function in children treated for posterior fossa tumours /

Cornwell, Petrea Lee. January 2003 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.

Page generated in 0.0335 seconds