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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.
21

Caractérisation spectroscopique et thermodynamique de l'organisation des lipides du Stratum Corneum

Arseneault, Marjolaine January 2005 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
22

Aspectos do desenvolvimento morfológico, morfométrico e ultraestrutural do aparelho ungueal do cavalo Baixadeiro / Aspects of morphological development, morphometric and ultrastructural the nail apparatus horse Baixadeiro

Anunciação, Adriana Raquel de Almeida da 15 March 2016 (has links)
O cavalo Baixadeiro é encontrado na Baixada Maranhense, região caracterizada por planície, podendo permanecer alagada por até seis meses. Ainda que diante destas condições, o cavalo Baixadeiro pode viver sem apresentar doenças da úngula, tais como, a laminite. Assim, propôs-se identificar elementos morfológicos da úngula desta raça específica de cavalo com o intuito de explicar tal resistência à umidade. Foram utilizadas amostras de úngula provenientes de 4 cavalos Baixadeiros (N=16) e de 4 cavalos Puro Sangue Inglês (N=16). Todas as úngulas foram analisadas por macroscopia, morfometria e por microscopia eletrônica de varredura e de luz. Macroscopicamente, a úngula do cavalo Baixadeiro era cuneiforme, com comprimento médio de 10.22 ± 1.3 cm, largura de 9.83 ± 1.01 cm e comprimento da parede medial de 5.67 ± 0.76 cm. A úngula do cavalo Puro Sangue Inglês teve um comprimento médio de 13.47 ± 0.8 cm, largura de 12.54 ± 0.49 cm e comprimento da parede medial de 7.77 ± 0.54 cm. Na microscopia de luz da camada interna, o tecido que conecta as lamelas epidérmicas primárias às secundárias e ao estrato médio foi visualmente mais espesso no Baixadeiro. Além disso, a região distal das lamelas era mais compacta do que as da região proximal, enquanto que no Puro Sangue Inglês não foram observadas diferenças. Na microscopia eletrônica de varredura, o espaço intertubular do estrato médio foi visualmente maior. A partir desta arquitetura nós sugerimos que existe maior adesão da cápsula da úngula à falange distal no cavalo Baixadeiro, provavelmente diminuindo a incidência de rotação da falange distal e, consequentemente, diminuindo a laminite / The Baixadeiro horse is found in Baixada Maranhense, region is characterized by a flat land that can be flooded during six months per year. In this region the Baixadeiro horse can live without ungula diseases, such as, laminitis. Thus, was proposed to identify morphological elements of the ungula from this specific breed to indicate this resistance to humidity. We used ungula samples from four Baixadeiro horse (N=16) and from four Thoroughbred horse (N=16). All ungulas were analyzed macroscopically, morphometrically and by light and scanning electronic microscopy. Macroscopically, the ungula of Baixadeiro horse was cuneiform, with average length 10.22 ± 1.3 cm, width of 9.83 ± 1.01 cm and medial wall lenght of 5.67 ± 0.76 cm. While the Thoroughbred horse ungula had average length 13.47 ± 0.8 cm, width 12.54 ± 0.49 cm and medial wall length 7.77 ± 0.54 cm. Under light microscopy, in the internal layer, the tissue that connects primary to secondary epidermal lamella and to middle stratum was visually thicker in the Baixadeiro. In addition, the distal region of lamellae was more compact than the proximal region, while in Thoroughbred no differences were observed. By scanning electron microscopy, the intertubular space of the middle stratum was visually bigger. From this architecture we suggested that there are greater adhesion of ugula capsule to distal phalanx in the Baixadeiro horse, probably decreasing incidence of distal phalanx rotation and consequently diminishing laminitis
23

3D property rights : an analysis of key factors based on international experience

Paulsson, Jenny January 2007 (has links)
The objectives of this thesis are to establish the fundamental principles in the field of 3D property rights by studying such systems in different countries with a particular focus on management questions, to systemize the acquired knowledge and demonstrate different ways of dealing with key factors essential to a well-functioning 3D property rights system. A theoretical background to the 3D property concept is given by presenting proposals as to a definition of 3D property and a classification of the primary forms of 3D property rights examined into specific types and categories, as well as an overview of international 3D property use. A general description of the characteristics of 3D property, with a focus on the condominium form, is also presented. A presentation of three different 3D property rights models is given as exemplified by the countries investigated, including the independent 3D property model in Sweden, the condominium form model in Germany, and a combination of the independent 3D property form and the condominium form as evidenced by the legal systems of two Australian states, New South Wales and Victoria. It has been possible to discern from this study a number of key factors related to 3D property rights that seem to be common for most forms and systems. These include the delimitation of property units, the content of the definition of common property, the creation of easements, the forms of cooperation between property units, management and regulation issues, as well as the settlement of disputes and insurance solutions. The problems experienced within the 3D property systems studied to a large extent have concerned issues within these mentioned key areas, where the management aspect seems particularly difficult. Changes in society and the creation of new development forms to a large extent have also contributed to the need for statutory amendments. More or less substantial amendments have been required in both the Australian and German statutes studied, with shortcomings still remaining after many years of use. However, these systems in general seem to be working well, and the condominium form in particular seems to be a well-functioning concept. Based on these systems, it has been possible to discern a tendency that the more detailed and complex the legislation, the greater the need for gradual amendments. In conclusion, it would be of benefit for countries planning on introducing a system for 3D property rights to utilize the experiences of other countries, while not forgetting to consider differences in legal systems, society, etc. / QC 20100812
24

Kallikrein-related peptidases in human epidermis : studies on activity, regulation, and function

Stefansson, Kristina January 2008 (has links)
Introduction. The outermost layer of the epidermis, the stratum corneum (SC), plays a fundamental role in our defense against microorganisms, chemicals, and dehydration. The SC is composed of tightly packed keratinized skin cells, corneocytes. For a functioning skin it is essential that corneocytes are constantly shed (desquamated). Kallikrein-related peptidase (KLK) 5 and KLK7 may be important in the desquamation process through degradation of desmosomal proteins. Severe hereditary diseases, where inhibition of KLK5 and/or KLK7 is missing, points to the importance of regulation of protease activity. KLKs may be regulated in various ways: tissue expression, activation of proforms, specific inhibitors, and physico-chemical properties like pH. Besides their involvement in desquamation, KLKs may also be important in immune defense and inflammation by processing of mediators and via activation of proteinase-activated receptors (PARs). Aims. 1. To identify and characterize previously unknown proteases in the SC. 2. To further characterize KLK5 and KLK7 with special focus on activation mechanisms. 3. To identify new inhibitors of KLKs in human SC. 4. To further characterize KLKs regarding effects of various inhibitors and substrates. 5. To study possible functions of KLKs in inflammation, in particular via activation of PAR-2. Methods. Plantar SC was used as a source for purification of proteins. Recombinant proteins were produced in different expression systems (insect cells, yeast cells, and bacteria). Different activity assays and kinetic studies were performed. Tissue expression was studied by immunohistochemistry, immunoblot and PCR. PAR-2 activation was studied by measurement of intracellular [Ca2+] and immunofluorescense in KNRK-PAR2 cells. Results. Active KLK14 was purified from extracts of plantar SC. KLK14 showed a superior catalytic efficiency as compared to KLK5 when measuring trypsin-like activity. This indicated that KLK14, despite being present in low amounts in skin, may have great relevance for skin physiology. Among enzymes tested only KLK5 showed autocatalytic activity and is so far the only enzyme found in SC that can activate proKLK7. KLK5 could also activate proKLK14. This together with studies of pH dependence on activation placed KLK5 as a possible key activating enzyme in a proposed proteolytic cascade in the SC. In plantar SC extracts we have also identified the novel Kazal-type serine protease inhibitor 9 (SPINK9). Our results indicate that SPINK9 is preferentially expressed in palmo-plantar skin and specific for KLK5. Differences found regarding substrate specificity and inhibition profile can be useful in evaluating the contribution of individual KLKs to the proteolytic activity in crude SC extracts. One interesting finding was that KLK8, present at high protein levels in the epidermis, could not be inhibited by any protease inhibitor found in the extracts. PAR-2 activation studies showed that KLK5 and 14 but neither KLK7 nor 8 can activate PAR-2. Immunohistochemistry preferentially detected KLK14 in intraepidermal parts of the sweat ducts and in dermal sweat glands but we could also show coexpression of KLK14 and PAR-2 in the SC and stratum granulosum of the epidermis in inflammatory skin disorders. To summarize, KLK involvement in desquamation may be dependent on a proteolytic activation cascade regulated by an intrinsic pH gradient and specific inhibitors present in SC. Another possible function of KLKs is as mediators of inflammation through activation of PAR-2.
25

The Value of Economy, Society and Polity of Kaohsiung Citizens from Different Stratum.

Wen, Chin-Ting 12 August 2009 (has links)
none
26

Efeitos de terpenos nas membranas de estrato córneo estudados por ressonância paramagnética eletrônica / Effects of terpenes on the stratum corneum membranes studied by electron paramagnetic resonance

Anjos, Jorge Luiz Vieira dos 18 February 2008 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-11-18T17:15:19Z No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-11-18T17:15:58Z (GMT) No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-18T17:16:00Z (GMT). No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2008-02-18 / The interaction of the skin penetration enhancers DL-menthol, -terpineol, 1,8-cineole and (+)-limonene with membranes of the uppermost skin layer, the stratum corneum (SC) and with multilamellar vesicles from 1,2-dipalmitoyl-sn-glycero-3-phosphaticylcholine (DPPC)is investigated by electron paramagnetic resonance (EPR) spectroscopy using spin-labeled analogs of androstanol ASL),stearic acid (5-DSA), methyl stearate (5-DMS) and a small spin label 2,2,6,6-tetramethylpiperedine-1-oxyl (TEMPO). The terpenes were added to SC samples using ethanol as a co-solvent (20% ethanol in the buffer), the effect of ethanol on the SC also was investigated. The spectra of spin labels ASL, 5-DSA and 5-DMS in the membranes of SC are characterized by the presence of two spectral components differing in mobility.Component 1 was attributed to the spin labels H-bonded to the headgroups, while component 2 was assigned to the spin labels H-bonded to water molecules or temporally non-hydrogen-bonded. EPR results showed that ethanol in the range 0-70% did not alter the fluidity in SC membranes or the relative fractions of these two components. Instead, ethanol only caused a selective extraction of spin labels, indicating that ethanol acts as extractor and not as fluidizer when facilitates molecular permeation in the skin. Addition of 1% DLmenthol to the solvent containing 20% ethanol increases both the mobility and the fraction of spin labels in the component 2 (more mobile spectral component). Similarly, with the addition of 1,8-cineole, the spin probes were gradually transferred from the motionally more restricted component 1 to the more mobile component 2. The spectrum of the spin label TEMPO in the membranes of SC allows for the determination of the actual partition coefficient and rotational diffusion rates of the spin probe in the aqueous and hydrocarbon environments. The enthalpy changes,H°,to transfer the spin probe from the aqueous to the hydrocarbon phase, as well as the activation energies associated to its rotational motion, were considerably smaller for SC when compared to DPPC, indicating less pronounced thermal reorganizations for SC samples. For DPPC,all terpenes increased both the partition coefficient and the rotational diffusion rate of the spin label in the membrane, except in the liquid-crystalline phase. These results suggest that the terpenes,effectively acting as spacers in the membrane,fluidize the lipids and cause ruptures in the hydrogen-bonded network of the membrane-water interface, with consequent displacements of spin probes towards the hydrophobic core. The EPR spectra of maleimide derivative spin label (6-MSL)covalently attached to stratum corneum proteins indicate that 1,8-cineole does not alter the dynamics of protein backbones.Instead, this terpene only increases the solvent s ability to dissolve and mobilize the nitroxide side chain, which is in agreement with its low irritation response. / A interação dos aumentadores de permeação da pele DL-mentol, -terpineol, 1,8-cineole e (+)-limoneno com as membranas da camada mais externa da pele, o estrato córneo (EC) e com vesículas multilamelares de 1,2-dipalmitoyl-sn-glycero-3-phosphaticylcholine (DPPC) foi investigado por espectroscopia de ressonância paramagnética eletrônica (RPE) utilizando marcadores de spin análogos do androstanol (ASL), acido esteárico (5-DSA) e estearato de metila (5-DMS), além de um pequeno marcador anfifílico, o 2,2,6,6-tetramethylpiperedine-1-oxyl (TEMPO), que se particiona entre as fases aquosa e hidrocarbônica. Como os terpenos foram adicionados ao EC usando soluções do etanol a 20% no tampão, foram também investigados os efeitos do etanol sobre as membranas do EC. Os espectros dos marcadores de spin ASL, 5-DSA e 5-DMS nas membranas de EC são caracterizados pela presença de duas componentes espectrais diferindo em mobilidade. A componente 1 foi atribuída aos marcadores de spin que formam ligações de hidrogênio com os grupos polares da membrana, enquanto que a componente 2 foi atribuída aos marcadores de spin que formam ligações de hidrogênio com as moléculas de água ou que, temporariamente, não estão formando ligações de hidrogênio. Os resultados de RPE mostraram que o etanol em concentrações variando de 0-70% não causa alteração de fluidez nem alteração das frações relativas das duas componentes espectrais. Ao invés disso, o etanol apenas causou uma seletiva extração dos marcadores lipídicos, indicando que os efeitos do etanol como facilitador advém de sua capacidade de extrair lipídios da membrana. Com a adição de 1% de L-mentol ao solvente contendo 20% de etanol houve um aumento tanto da mobilidade quanto da fração dos marcadores de spin da componente 2 (componente espectral mais móvel). Analogamente, com a adição de 1,8-cineole, os marcadores de spin foram gradualmente transferidos da componente 1, de mobilidade mais restrita, para a componente 2 mais móvel. O espectro do marcador de spin TEMPO nas membranas de EC permite determinar o coeficiente de partição e a taxa de difusão rotacional do marcador de spin nos ambientes aquoso e hidrofóbico. As mudanças de entalpia, H°, para transferir o marcador de spin da fase aquosa para fase hidrocarbônica, bem como as energias de ativação associadas com o movimento rotacional, foram consideravelmente menores para o EC em relação às amostras de DPPC, indicando reorganizações térmicas menos pronunciadas para as membranas do EC. Para DPPC, todos os terpenos aumentaram tanto o coeficiente de partição quanto a taxa de difusão rotacional dos marcadores de spin na membrana, exceto na fase líquido-cristalina. Estes resultados sugerem que os terpenos agem efetivamente como espaçadores dos lipídios da membrana reduzindo seu empacotamento e aumentando sua fluidez, desse modo causando rupturas da rede de ligações de hidrogênio na interface membrana-água e assim gerando deslocamentos dos marcadores de spin para o core hidrofóbico. O espectro de RPE do marcador de spin derivado do maleimido (6-MSL) covalentemente ligado às proteínas do EC indicou que o 1,8-cineole não altera a dinâmica do esqueleto protéico. Ao invés disso, este terpeno apenas aumenta a habilidade do solvente em dissolver e mobilizar a cadeia lateral do nitróxido, o que está em acordo com seu baixo potencial de irritação.
27

Aspectos do desenvolvimento morfológico, morfométrico e ultraestrutural do aparelho ungueal do cavalo Baixadeiro / Aspects of morphological development, morphometric and ultrastructural the nail apparatus horse Baixadeiro

Adriana Raquel de Almeida da Anunciação 15 March 2016 (has links)
O cavalo Baixadeiro é encontrado na Baixada Maranhense, região caracterizada por planície, podendo permanecer alagada por até seis meses. Ainda que diante destas condições, o cavalo Baixadeiro pode viver sem apresentar doenças da úngula, tais como, a laminite. Assim, propôs-se identificar elementos morfológicos da úngula desta raça específica de cavalo com o intuito de explicar tal resistência à umidade. Foram utilizadas amostras de úngula provenientes de 4 cavalos Baixadeiros (N=16) e de 4 cavalos Puro Sangue Inglês (N=16). Todas as úngulas foram analisadas por macroscopia, morfometria e por microscopia eletrônica de varredura e de luz. Macroscopicamente, a úngula do cavalo Baixadeiro era cuneiforme, com comprimento médio de 10.22 ± 1.3 cm, largura de 9.83 ± 1.01 cm e comprimento da parede medial de 5.67 ± 0.76 cm. A úngula do cavalo Puro Sangue Inglês teve um comprimento médio de 13.47 ± 0.8 cm, largura de 12.54 ± 0.49 cm e comprimento da parede medial de 7.77 ± 0.54 cm. Na microscopia de luz da camada interna, o tecido que conecta as lamelas epidérmicas primárias às secundárias e ao estrato médio foi visualmente mais espesso no Baixadeiro. Além disso, a região distal das lamelas era mais compacta do que as da região proximal, enquanto que no Puro Sangue Inglês não foram observadas diferenças. Na microscopia eletrônica de varredura, o espaço intertubular do estrato médio foi visualmente maior. A partir desta arquitetura nós sugerimos que existe maior adesão da cápsula da úngula à falange distal no cavalo Baixadeiro, provavelmente diminuindo a incidência de rotação da falange distal e, consequentemente, diminuindo a laminite / The Baixadeiro horse is found in Baixada Maranhense, region is characterized by a flat land that can be flooded during six months per year. In this region the Baixadeiro horse can live without ungula diseases, such as, laminitis. Thus, was proposed to identify morphological elements of the ungula from this specific breed to indicate this resistance to humidity. We used ungula samples from four Baixadeiro horse (N=16) and from four Thoroughbred horse (N=16). All ungulas were analyzed macroscopically, morphometrically and by light and scanning electronic microscopy. Macroscopically, the ungula of Baixadeiro horse was cuneiform, with average length 10.22 ± 1.3 cm, width of 9.83 ± 1.01 cm and medial wall lenght of 5.67 ± 0.76 cm. While the Thoroughbred horse ungula had average length 13.47 ± 0.8 cm, width 12.54 ± 0.49 cm and medial wall length 7.77 ± 0.54 cm. Under light microscopy, in the internal layer, the tissue that connects primary to secondary epidermal lamella and to middle stratum was visually thicker in the Baixadeiro. In addition, the distal region of lamellae was more compact than the proximal region, while in Thoroughbred no differences were observed. By scanning electron microscopy, the intertubular space of the middle stratum was visually bigger. From this architecture we suggested that there are greater adhesion of ugula capsule to distal phalanx in the Baixadeiro horse, probably decreasing incidence of distal phalanx rotation and consequently diminishing laminitis
28

Pathophysiologie und Immunologie der Hautreagibilität gegenüber NaOH.

Khrenova, Liubov 29 April 2008 (has links)
Die individuelle Hautempfindlichkeit stellt einen bedeutsamen Risikofaktor für die Entwicklung von berufsbedingten Hauterkrankungen dar. Zur Beurteilung der Hautempfindlichkeit hat sich in der Berufsdermatologie der Alkaliresistenztest als Standardverfahren etabliert. Er wird heute in vielen methodischen Varianten durchgeführt, was eine einheitliche Beurteilung und Begutachtung von Versicherten mit Berufsdermatosen wesentlich erschwert. Außerdem fehlt trotz bestehender Standardisierungs- und Qualitätskriterien eine allgemeingültige Standardisierung der Hautirritabilitätsdiagnostik im Sinne einer Leitlinie. Das Ziel der vorliegenden Arbeit war zum einen, die aktuelle Hautempfindlichkeitsdiagnostik bundesweit zu vereinheitlichen, zum anderen, neue Testverfahren zu entwickeln, die nicht nur schneller durchzuführen sind, sondern auch mit weniger Belastungen für die Patienten einhergehen. Der Schnelle Modifizierte Alkali-Resistenz-Test (SMART) und der Differenzielle IrritationsTest (DIT) wurden im Rahmen einer Multicenter-Studie hinsichtlich der Praktikabilität im Einsatz bei den berufsdermatologischen Routineuntersuchungen evaluiert. Die Studie zeigte, dass weder klinische noch hautphysiologische Testergebnisse von den erfassten Umgebungsfaktoren wesentlich beeinflusst werden. Auf der Grundlage der vorliegenden Ergebnisse können der SMART und der DIT sowohl zur Identifizierung vermehrter konstitutioneller Risiken als auch zur Objektivierung einer resultierenden subklinischen Minderbelastbarkeit der Haut der Hände nach früherem, abgeheiltem Berufsekzem eingesetzt werden. In der zweiten Studie wurden immunologische Ursachen individueller Hautempfindlichkeit mittels der Abrissmethode untersucht. Auf der Basis der Ergebnisse dieser Studie lässt sich schlussfolgern, dass es noch nicht möglich ist, anhand eines Tesafilmabrisses eine Aussage zur individuellen Hautempfindlichkeit zu erhalten. Hierzu erscheinen weitere Forschungsprojekte mit größeren Stichproben erforderlich.
29

Mechanisms of anionic surfactant penetration into human skin

Ventura, Stephanie A. 11 June 2019 (has links)
No description available.
30

Lipid composition and molecular interactions in the stratum corneum of birds in response to differences in environment

Champagne, Alex Michael 14 November 2014 (has links)
No description available.

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