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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.
71

Estudo morfométrico em rins de felinos domésticos (Felis catus) / Morphometric study in kidneys of cats (Felis catus)

Agopian, Rafael Garabet 18 December 2014 (has links)
A saúde renal tem ao longo dos últimos anos chamado atenção dos médicos veterinários, pois o comprometimento deste órgão na insuficiência renal crônica se apresenta como a maior causa de morbidade e mortalidade em felinos. O presente estudo propõe a caracterização biométrica dos rins de gatos, Felis catus, sob os aspectos macroscópico (comprimento, altura, largura, peso e volume), mesoscópico (altura do córtex e da medula, e a sua inter-relação) e microscópica (volume glomerular), a fim de se estabelecer possíveis diferenças decorrentes de idade, sexo e simetria bilateral. Foram utilizados, rins de 30 animais da espécie Felis catus (gato deméstico), sendo 15 machos e 15 fêmeas com idade variando entre 3 meses a 15 anos, divididos em três grupos: grupo 1 (3 a 9 meses), grupo 2 (3 a 5 anos) e grupo 3 (acima de 10 anos). Os rins foram fotografados, pesados, mensurados e processados para histologia. O volume glomerular foi obtido através de estereologia. Os dados macroscópicos permitiram observar uma imparcialidade morfométrica e morfológica quando comparados os lados, independente do grupo e do sexo, sobre o comprimento, altura, largura, peso e volume dos rins. Para o sexo foi detectado diferença significante entre machos e fêmeas independente da faixa etária para comprimento, altura, peso e volume, com exceção da largura. Considerando a idade houve diferença significativa para todos os parâmetros: comprimento, altura, largura, peso e volume. Nas mensurações de córtex, medula e sua inter-relação, quando considerada a simetria bilateral, não foi detectada diferença significante entre rim direito e esquerdo. Para o sexo, não foi detectada diferença entre machos e fêmeas na mesoscopia no córtex, na medula e na inter-relação córtex / medula. Quanto à idade, a mensuração da altura do córtex e a inter-relação córtex / medula apresentou diferença significante, porém essa diferença não foi estabelecida para a medula do rim. Foram encontradas diferenças significantes entre grupos e entre machos e fêmeas, em relação ao volume ocupado pelo glomérulo no parênquima renal. Em todas as técnicas biométricas utilizadas não foram detectadas diferenças entre os rins direito e esquerdo. As mensurações macroscópicas mostraram que machos apresentaram um rim maior em comprimento, altura, largura, peso e volume do que as fêmeas. A faixa etária está diretamente relacionada ao tamanho do rim, que cresce em todas as dimensões, fica mais pesado e com maior volume quando comparados jovens e adultos, e se mostra estável morfometricamente em relação aos adultos e senis. O parênquima renal não difere entre os sexos, mas a altura do córtex e a relação com a medula aumentam com a idade. O volume do glomérulo renal é maior em machos do que em fêmeas e também aumenta em relação à idade. Os rins mostraram um predomínio de colágeno tipo I nos animais do grupo 1 e 2, e colágeno tipo III nos animais do grupo 3 / Renal Health has over the last few years called attention from veterinarians because of the commitment of this organ in chronic renal failure presents itself as a major cause of morbidity and mortality in cats. This paper proposes biometric characterization of the kidneys from cats, Felis catus, on the macroscopic aspects (length, height, width, weight and volume), mesoscopic (height of the cortex and medulla, and their inter-relationship) and microscopic (glomerular volume) in order to establish possible differences arising from age, gender and bilateral symmetry. It where used 30 kidneys of animals from specie Felis Catus (cat), 15 males and 15 females with ages between 3 months to 15 years, divided into three groups: group 1 (3-9 months), group 2 (3 - 5 years) and group 3 (above 10 years). The kidneys were photographed, weighed, measured and processed for histology. The glomerular volume was obtained by stereology. The macroscopic data allowed to observe a morphometric and morphologic impartiality when compared sides, regardless of group and sex, about the length, height, width, weight and kidney volume. Significant difference was detected between males and females regardless of age for length, height, weight and volume, except for the width. There was a significant difference for all parameters considering the age: length, height, width, weight and volume. Wasnt detected signficant diferences between left and right kdney measurements of cortex, medulla and their inter-relationship, when considered bilateral symmetry. No difference was detected between males and females in mesoscopy in the cortex, medulla and cortex interrelationship cortex / medulla. Regarding age, the measurement of the height of the cortex and the interrelationship cortex / medulla showed a significant difference, but this difference was not established to the medulla of the kidney. Significant differences were found between groups, males and females, compared to the volume occupied by the glomerulus on the parenchyma renal. In all of biometric techniques there wasnt differences between right and left kidneys. The macroscopic measurements showed that males had larger kidney when compared length, height, width, weight and volume than females. The age range is directly related to the size of the kidney, which grows in all dimensions, gets heavier and with higher volume when compared young adults, and shows morphometry stability in relation to adults and senile. The renal parenchyma did not differ between the sexes, but the height of the cortex and the medulla ratio increases with age. The volume of the renal glomerulus is higher in males than in females and also increases in with the age. The kidneys showed a predominance of type I collagen in group 1 and 2, and type III collagen in group 3
72

Neuronenquantifizierung des menschlichen Nucleus subthalamicus und morphologische Untersuchung des Kerngebietes mittels stereologischer Mikroskopie

Möbius, Dustin 07 February 2018 (has links)
No description available.
73

Ultrasound Measurement of Change in Kidney Volume Is a Sensitive Indicator of Severity of Renal Parenchymal Injury

Crislip, G. Ryan, Patel, Bansari, Mohamed, Riyaz, Ray, Sarah C., Wei, Qingqing, Sun, Jingping, Polichnowski, Aaron J., Sullivan, Jennifer C., O’Connor, Paul M. 28 August 2020 (has links)
Ultrasound measurement of change in kidney volume is a sensitive indicator of severity of renal parenchymal injury. Am J Physiol Renal Physiol 319: F447–F457, 2020. First published July 20, 2020; doi:10.1152/ajprenal.00221.2020.—Noninvasive determination of the severity of parenchymal injury in acute kidney injury remains challenging. Edema is an early pathological process following injury, which may correlate with changes in kidney volume. The goal of the present study was to test the hypothesis that “increases in kidney volume measured in vivo using ultrasound correlate with the degree of renal parenchymal injury.” Ischemia-reperfusion (IR) of varying length was used to produce graded tissue injury. We first determined 1) whether regional kidney volume in rats varied with the severity (0, 15, 30, and 45 min) of warm bilateral IR and 2) whether this correlated with tubular injury score. We then determined whether these changes could be measured in vivo using three-dimensional ultrasound. Finally, we evaluated cumulative changes in kidney volume up to 14 days post-IR in rats to determine whether changes in renal volume were predictive of latent tubular injury following recovery of filtration. Experiments concluded that noninvasive ultrasound measurements of change in kidney volume over 2 wk are predictive of tubular injury following IR even in animals in which plasma creatinine was not elevated. We conclude that ultrasound measurements of volume are a sensitive, noninvasive marker of tissue injury in rats and that the use of three-dimensional ultrasound measurements may provide useful information regarding the timing, severity, and recovery from renal tissue injury in experimental studies.
74

Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) and blood vessel density changes in an experimental model of Chronic Hydrocephalus

Deshpande, Abhishek 16 July 2010 (has links)
No description available.
75

The Role of Microstructure on High Cycle Fatigue Lifetime Variability in Ti-6Al-4V

Polasik, Alison K. January 2014 (has links)
No description available.
76

Development of an automated characterization-representation framework for the modeling of polycrystalline materials in 3D

Groeber, Michael Anthony 30 August 2007 (has links)
No description available.
77

Stereological Interpretation of Rock Fracture Traces on Borehole Walls and Other Cylindrical Surfaces

Wang, Xiaohai 11 October 2005 (has links)
Fracture systems or networks always control the stability, deformability, fluid and gas storage capacity and permeability, and other mechanical and hydraulic behavior of rock masses. The characterization of fracture systems is of great significance for understanding and analyzing the impact of fractures to rock mass behavior. Fracture trace data have long been used by engineers and geologists to character fracture system. For subsurface fractures, however, boreholes, wells, tunnels and other cylindrical samplings of fractures often provide high quality fracture trace data and have not been sufficiently utilized. The research work presented herein is intended to interpret fracture traces on borehole walls and other cylindrical surfaces by using stereology. The relationships between the three-dimension fracture intensity measure, P32, and the lower dimension fracture intensity measures are studied. The analytical results show that the conversion factor between the three-dimension fracture intensity measure and the two-dimension intensity measure on borehole surface is not dependent on fracture size, shape or circular cylinder radius, but is related to the orientation of the cylinder and the orientation distribution of fractures weight by area. The conversion factor between the two intensity measures is determined to be in the range of [1.0, π/2]. The conversion factors are also discussed when sampling in constant sized or unbounded fractures with orientation of Fisher distribution. At last, the author proposed estimators for mean fracture size (length and width) with borehole/shaft samplings in sedimentary rocks based on a probabilistic model. The estimators and the intensity conversion factors are tested and have got satisfactory results by Monte Carlo simulations. / Ph. D.
78

Exercise-induced muscle soreness : a qualitative and quantitative study of human muscle morphology and function

Fridén, Jan January 1983 (has links)
Exercise-induced muscle soreness is characterized by stiffness, tenderness and pain during active movements and weakness of the affected musculature the days after unusually or particularly heavy work. The most pronounced subjective symptoms do not arise immediately but rather between a couple of hours to some days after the exercise (a delayed-onset of muscle soreness), the intensity of pain is greatest about 48 hours after the work. A particular association exists between muscle soreness and eccentric contractions. Despite the fact that muscle soreness is a well known phenomenon in the sphere of sports as well as working life, the pathophysiological mechanisms underlying this are still not understood. In the present study a detailed analysis of human muscle fibre population structure after high tension work (eccentric exercise) that gave rise to muscle soreness, was carried out. The objective was to elucidate how fibres of different types are influenced by repeated muscle contractions reaching extreme tension levels using qualitative and quantitative light and electron microscopic techniques. It was hoped that such morphological analysis would provide a basis for discussion of possible causes for muscle soreness. The muscle function after the work was measured by isokinetic methods. To improve the basis for the ultrastructural analysis the fibre populations in untrained and en­durance trained human m. vastus lateralis of age-matched individuals were classified into different fibre type groups according to their ultrastructure. The selective glycogen depletion from Type 1 fibres seen after long term submaximal work, visualized electron microscopically with PA-TSC-SP staining, substantiated the usefulness of the appearance of the M-band to differentiate between fibre types. Stereological data showed that neither volume density of mitochondria nor of lipid droplets provide sufficient criteria to differentiate between fibre types. After an eccentric exercise regimen sore muscles (m. soleus or m. vastus lateralis) showed disturb­ances of the cross striated band pattern. Fibres with disorganized myofibrillar material made up 1/3, 1/2 and 1/10 of the analysed material, 1 hour, 3 and 6 days after exercise, respectively. The myofibril­lar lesions were preferably localized in the Z-band. This showed streaming, broadening and sometimes total disruption. The Type 2 fibres were most affected. The reduction of strength was greatest with the most rapid contractions. Strength remained de­creased the period when the structural damage was most pronounced. Eight weeks of eccentric muscle training reduced all the above negative effects. The results indicate that the Z-disc constitute the weak link in the myofibrillar contractile chain at high muscle tensions. It is suggested that the myofibrillar lesions are a direct result of mechanical tearing. Rupture of myofibrils is thought to result in formation of protein components and a con- sequental release of protein bound ions that via osmosis result in oedema and soreness. Training, using eccentric contractions over a long period of time leads to adaptations at the fibre level by a reorgani­zation of the contractile apparatus as well as an optimization of nervous coordination. / <p>S. 1-40: sammanfattning, s. 41-79: 5 uppsatser</p> / digitalisering@umu
79

Estudo quantitativo das células granulares adenohipofisárias associadas à produção do hormônio de crescimento e avaliação do perfil bioquímico do IGF-I em cães Golden Retriever com Distrofia Muscular (GRMD) / Morphometric and stereological study of the adenohypophysis granular cells associated to GH producing and evaluation of the biochemical profile of IGF-I in golden retriever muscular dystrophy (GRMD)

Lima, Ana Rita de 14 June 2005 (has links)
A Distrofia Muscular de Duchenne (DMD) é uma doença recessiva ligada ao cromossomo ?X?, causada pela ausência da proteína distrofina que ocorre em vários tecidos, sendo caracterizada por uma severa disfunção da musculatura esquelética ocasionando morte prematura do paciente. Embora controverso, alguns autores reportaram que o GH (hormônio do crescimento) estaria implicado no desenvolvimento da doença e poderia ser utilizado no tratamento da mesma. Desta forma, neste estudo a dosagem sérica de IGF-I (Fator I de crescimento Similar à insulina) um peptídeo GH-dependente que regula as ações do hormônio do crescimento, foi realizada no intuito de verificar se existe correlação ou não entre o desenvolvimento da doença e a concentração sérica de IGF-I. As variações nos níveis deste hormônio foram demonstradas com o decorrer da idade sendo que, nos três primeiros meses todos os animais apresentaram comportamento semelhante com aumento dos níveis de IGF-I, porém no quarto mês os animais Distróficos benignos apresentaram redução média de 34% deste hormônio, enquanto ocorreu aumento de 1% no animal não Distrófico. Ainda, as células granulares adenohipofisárias relacionadas à produção do hormônio de crescimento em cães Golden Retriever com Distrofia Muscular apresentam-se maiores do que nos cães Golden Retriever não distróficos quanto aos seguintes parâmetros (eixo longo, área seccional e volume celular). À microscopia eletrônica de transmissão observamos que as células estudadas apresentam grânulos elétron-densos de parede dupla e distribuídos por todo o citosol. Estes grânulos apresentaram-se maiores nos animais Distróficos quando comparados aos animais não Distróficos. / The Duchenne Muscular Dystrophy (DMD) is a X linked recessive disease, caused by the absence of dystrophin which is found in a variety of tissues and characterized by a severe disfunction of the skeletal musculature that results in a premature death of the patient. Theoretically, the growth hormone (GH) is considered to be associated to the development of Muscular Dystrophy and that could be used in its treatment. Hence in this study, a IGF-I (Insulin like growth factor-I) seric dosage was performed to verify whether or not there might be a between the evolution of the disease and IGF´s seric concentration. IGF-I is a GH-peptide dependent that regulates the GH actions during the growth. Changes in IGF-I levels were recorded during the dog?s post-natal development. On the first trimester, all animals presented similar IGF-I levels, although in the fourth month, a stark 34% decrease was observed in the dystrophic animals whereas a 1% increase was seen in the healthy dog. Furthermore, the GRMD´s granule-containing cells were larger when compared to the healthy animals. The following parameters in this comparison: long axis, cross-sectional area and cell volume. The ultrastructural study showed electron-dense granules composed by a double membrane and homogeneously distributed through the cell. These granules were larger in the dystrophic animals then in healthy dogs.
80

Mecanismos de proliferação neuronal pós-natal no gânglio cervical cranial de preás (Galea spixii spixii) Wagler, 1831. Neurogênese x diferenciação neuronal tardia / Mechanisms of the post-natal neuronal proliferation in the cranial cervical ganglion of preás (Galea spixii spixii) Wagler, 1831. Neurogenesis vs late neuronal differentiation

Ladd, Aliny Antunes Barbosa Lobo 15 September 2009 (has links)
Neste estudo, foram abordados os aspectos quantitativos do gânglio cervical cranial (GCC) esquerdo de preás (Galea spixii spixii) machos, oriundos do criatório da Universidade Federal Rural do Semi-Árido Nordestino de Mossoró-RN. Os seguintes parâmetros foram estimados: volume do GCC, número total e tamanho dos neurônios (uni e binucleados) durante dois períodos do desenvolvimento pós-natal (maturação e envelhecimento). Para tanto, utilizamos quatro grupos etários distintos de animais: neonatos, jovens, adultos e senis. Após a eutanásia dos animais, os GCCs foram fixados (perfusão sistêmica) com solução de formoldeído (4%) em PBS, embebidos em solução de ágar (10%) e seccionados sistemática, uniforme e aleatoriamente, aplicando-se o princípio de amostragem e contagem do fractionator. Os principais resultados desta pesquisa foram: houve diferença significativa entre os grupos etários para os parâmetros: Peso Neonato: 0,00056 ; Jovem: 0,00084; Adulto: 0,00116; Senil: 0,00118. Comprimento Neonato: 1,294 ; Jovem: 2,076; Adulto: 2,304; Senil: 2,082. Largura Neonato: 0,842; Jovem: 1,028; Adulto: 1,062; Senil: 1,174. Volume ganglionar Neonato: 0,34 mm3 ; Jovem: 0,30 mm3; Adulto: 0,39 mm3; Senil: 0,63 mm3 e Volume neuronal médio de neurônios uninucleados Neonato: 2916,90 mm3; Jovem: 3550,00 mm3; Adulto: 7409,00 mm3; Senil: 6701,00 mm3. As principais conclusões deste estudo foram: (i) peso, comprimento e largura do GCC apresentaram aumento significativo de 185%, 60% e 79% respectivamente, durante o período de maturação, enquanto durante o período de envelhecimento, o peso do GCC apresentou queda de 33%, o comprimento um pequeno decréscimo de 10%, entretanto a largura, durante este mesmo período, apresentou um aumento progressivo de mais de 10%, tais alterações relacionadas com a idade refletiram no volume ganglionar, causando hipertrofia; (ii) Essa hipertrofia do GCC de preás é secundária ao desenvolvimento pós-natal (maturação e envelhecimento), aumentando em 85%, acompanhado por um aumento alométrico, da ordem de 6 vezes em relação à massa corporal, aproximadamente 622%; (iii) Há hipertrofia dos neurônios uninucleados que é secundária ao desenvolvimento pós-natal do GCC de preás, aumentando em 154% durante o período de maturação com uma pequena queda de 10% durante o envelhecimento. Finalmente, sugere-se que estudos futuros possam investigar se o tamanho dos territórios de inervação destes gânglios pode desencadear mudanças na micro e macroestrutura dos mesmos, incluindo a possibilidade de ocorrência de neurogênese, que seria estudada por meio de imunomarcadores específicos. / This study aimed at detecting whether post-natal development would exert any effect on the size and number of cranial cervical ganglion (CCG) neurons of male preas (Galea spixii spixii). Twenty left CCGs from twenty preas were harvested from the Animal Facility of the Universidade Federal Rural do Semi-Árido Nordestino, Mossoró- RN and were divided into four different age groups: newborn, young, adult and aged subjects. The following parameters were estimated using Cavalieri\'s principle and optical fractionator and planar rotator , respectively: the volume of CCG, total number and mean volume of uni and binucleate neurons. After euthanasia, the CCGs were perfusion-fixed with a 4% formaldehyde solution in PBS, agar-embedded and, SUR vibrosectioned. The ganglion volume was 0.34 mm3 (newborn), 0.30 mm3 (young), 0.39 mm3 (adult) and 0.63 mm3 (aged animals) (p= 0,012). The mean volume of uninucleate neurons was 2,917 mm3 (newborn), 3,550 mm3 (young), 7,409 mm3 (adult) and 6,701 mm3 (aged animals) (p=0,0001). The main conclusions of this study were: (i) The CCG hypertrophy - 85% - is the result of post-natal development (maturation and ageing), (ii) a 154% increase (hypertrophy) in the volume of uninucleate neurons during the maturation is followed by a 10% atrophy of them during ageing. Future studies may investigate whether the size of the CCG\'s target-organs can affect the structural foundation of CCG and, therefore, add further fuel to the notion that a post-natal neurogenesis may indeed exist in sympathetic ganglia.

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