• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 15
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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.
1

Taxonomy and reproductive biology of some woody Rosaceae

Dunkley, Harvey January 1989 (has links)
No description available.
2

Isolation, characterization and pharmacokinetics of antioxidants from Hawthorn. / CUHK electronic theses & dissertations collection

January 2002 (has links)
Qi Chang. / "March 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 173-192). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
3

Lietuvoje augančių gudobelės (Crataegus L.) genties augalų fitocheminės sudėties įvertinimas / Evaluation of phytochemical composition of plants of genus hawthorn (Crataegus L.) growing in Lithuania

Jakštas, Valdas 20 September 2005 (has links)
EVALUATION OF PHYTOCHEMICAL COMPOSITION OF PLANTS OF GENUS HAWTHORN (CRATAEGUS L.) GROWING IN LITHUANIA INTRODUCTION For the last fifteen years, the attention of doctors and their patients on drugs and food supplements of herbal origin has been continuously increasing. The growing interest in raw plant materials is expanding the possibilities of use of these materials in the industries of medicine, cosmetics and food as well as encouraging assessment and description of natural resources using new modern methods. Scientific research on natural herbal resources has bee receiving special attention in the European Union. In recent years, a number of important documents have been published in the European Union, which declare the aims of ensuring the use and quality of natural herbal resources, such as Good Agricultural Practice document, Points to consider on Good agricultural and collection practice for starting materials of herbal origin, a long term vision of the future of herbal biotechnology in Europe Plants for the Future. Cardiovascular system diseases constitute one of the most urgent health problems. The range of effective herbal preparations for the target phytotherapy of cardiovascular system diseases is not wide. Hawthorn preparations are a promising drug for the treatment of cardiovascular system diseases, whose pharmacological effects have been substantiated by scientific studies. Throughout the territory of Lithuania, three kinds of hawthorn can be found growing... [to full text]
4

Effects of Soil Amendments and Biostimulants on the Post-transplant Growth of Landscape Trees

Kelting, Matthew P. 07 February 1997 (has links)
Use of soil amendments at planting is one of the time-honored traditions in horticulture, although their effectiveness has been questioned by many. Recently, humate and humate-based products, generally known as biostimulants, have been marketed to increase transplant success. In this study, three experiments were conducted to examine the effects of soil amendments and biostimulants on post-transplant growth of landscape trees. The first experiment, conducted in a greenhouse, determined the effects of several biostimulant treatments (granular humate, water-soluble humate, liquid humate, liquid humate+ = humic acid, hormones, and vitamins) and fertilizer levels (low, medium, high) on the growth of container-grown Corylus colurna L. (Turkish hazelnut) seedlings. Biostimulants did not increase top growth compared to control treatments, but root growth was increased by granular humate at a medium fertilizer rate. The second experiment examined the effects of biostimulants (granular humate, water-soluble humate, liquid humate+) on the post-transplant root growth and sap-flow of landscape-sized balled and burlapped Acer rubrum L. (red maple) grown in root observation compartments (rhizotrons). Biostimulants did not increase root growth over control treatments, but sap-flow was increased. The third experiment, conducted in the field (Groseclose silt loam soil) investigated the effects of soil amendments (peat, and compost) and biostimulants (granular humate, and liquid humate+) on the post-transplant growth of Crataegus phaenopyrum (Blume) Hara (Washington hawthorn) and red maple transplanted bare-root, and grown under combinations of irrigated vs non-irrigated and fertilized-at-planting vs non-fertilized-at-planting regimes. Hawthorn controls generally had less top growth than the other soil treatments as a whole. No soil treatment was higher than control for top growth of red maple. However, root growth of red maple was highest in the peat-treated trees. Stem diameter and dry mass for the control and compost treatments were higher than the biostimulant treatments in irrigated plots, but no differences were observed in non-irrigated plots. Granular humate-treated trees resulted in higher stem diameter and dry mass than the liquid humate+-treated trees in non-irrigated plots. There were no effects of fertilizer, or irrigation on growth after two growing seasons for either species. / Master of Science
5

Global and Fine Scale Molecular Studies of Polyploid Evolution in Crataegus L. (Rosaceae)

Lo, Eugenia Yuk Ying 19 January 2009 (has links)
As many as 70% of angiosperm species are known to contain polyploids, but many aspects of polyploid evolution are unclear in woody plants. Crataegus is a woody genus of Rosaceae comprising 140-200 species that are widely distributed in the Northern Hemisphere. Several species, particularly those in North America, are shown to contain polyploids. The overall goal of the thesis is to provide a better understanding of polyploid evolution by resolving problems from intergeneric to intraspecific levels in Crataegus using phylogenetic and population genetic approaches. Three major aspects were investigated: (1) Phylogeography of the Old and New World Crataegus; (2) Reproductive system and distribution of cytotypes of the black-fruited series Douglasianae in Pacific Northwest and; (3) Origins, population structure, and genetic diversity of diploid and polyploid species. Phylogenetic analyses of molecular data provide evidences of historical events such as trans-Beringian migrations and North Atlantic vicariance that contributed to modern distribution of Crataegus. Poor resolution and short internal branches in eastern North American species suggest genetic bottlenecks and/or rapid divergence following glaciations. In the Pacific Northwest, polyploids of series Douglasianae show a wider distribution and ecological amplitude than diploids. Parsimony tree and network analyses indicate that autotriploids and allotriploids occur in C. suksdorfii, while tetraploid C. suksdorfii are formed via the triploid bridge followed by introgression of sympatric C. douglasii. At the regional level, microsatellite data indicate a separation of the Pacific coastal diploids and triploids from the Columbia Plateau and Rocky Mountain triploids and tetraploids. High genetic differentiation among C. suksdorfii populations suggests that gene flow is limited by ploidy level differences as well as geographical distance. Within-population multilocus genotypic variation is greatest in sexual diploids, and least in apomictic triploids. Frequent gene flow via seed dispersal contributes to an appreciable level of intrapopulation diversity in apomictic tetraploids, and counterbalances the effects of apomixis and/or self-fertilization, which diminish genetic variation within and between seed families. These findings collectively clarify taxonomy and historical biogeography, provide an explicit reticulation model for polyploid formation, and shed light on evolution of natural populations in woody plants that show heterogeneous ploidy levels and reproductive systems.
6

Global and Fine Scale Molecular Studies of Polyploid Evolution in Crataegus L. (Rosaceae)

Lo, Eugenia Yuk Ying 19 January 2009 (has links)
As many as 70% of angiosperm species are known to contain polyploids, but many aspects of polyploid evolution are unclear in woody plants. Crataegus is a woody genus of Rosaceae comprising 140-200 species that are widely distributed in the Northern Hemisphere. Several species, particularly those in North America, are shown to contain polyploids. The overall goal of the thesis is to provide a better understanding of polyploid evolution by resolving problems from intergeneric to intraspecific levels in Crataegus using phylogenetic and population genetic approaches. Three major aspects were investigated: (1) Phylogeography of the Old and New World Crataegus; (2) Reproductive system and distribution of cytotypes of the black-fruited series Douglasianae in Pacific Northwest and; (3) Origins, population structure, and genetic diversity of diploid and polyploid species. Phylogenetic analyses of molecular data provide evidences of historical events such as trans-Beringian migrations and North Atlantic vicariance that contributed to modern distribution of Crataegus. Poor resolution and short internal branches in eastern North American species suggest genetic bottlenecks and/or rapid divergence following glaciations. In the Pacific Northwest, polyploids of series Douglasianae show a wider distribution and ecological amplitude than diploids. Parsimony tree and network analyses indicate that autotriploids and allotriploids occur in C. suksdorfii, while tetraploid C. suksdorfii are formed via the triploid bridge followed by introgression of sympatric C. douglasii. At the regional level, microsatellite data indicate a separation of the Pacific coastal diploids and triploids from the Columbia Plateau and Rocky Mountain triploids and tetraploids. High genetic differentiation among C. suksdorfii populations suggests that gene flow is limited by ploidy level differences as well as geographical distance. Within-population multilocus genotypic variation is greatest in sexual diploids, and least in apomictic triploids. Frequent gene flow via seed dispersal contributes to an appreciable level of intrapopulation diversity in apomictic tetraploids, and counterbalances the effects of apomixis and/or self-fertilization, which diminish genetic variation within and between seed families. These findings collectively clarify taxonomy and historical biogeography, provide an explicit reticulation model for polyploid formation, and shed light on evolution of natural populations in woody plants that show heterogeneous ploidy levels and reproductive systems.
7

Estudo da toxicidade hepática e esplênica do extrato de Crataegus oxyacantha em camundongos análises histológicas /

Santos, Jéssica Cristina dos January 2017 (has links)
Orientador: Edson Luis Maistro / Resumo: Embora a medicina moderna esteja bem desenvolvida, de acordo com a Organização Mundial da Saúde, cerca de 75 à 95% da população utiliza a medicina popular para alívio de alguma sintomatologia desagradável. A grande preocupação é que mesmo as plantas medicinais sendo muito utilizadas, não se tem um conhecimento completo sobre sua ação no organismo. A planta Crataegus oxyacantha, também conhecida como espinheiro branco ou Hawthorn, é originária da Europa, América do Norte e Ásia, foi levada para outros continentes e vem sendo muito utilizada devido a seus potenciais efeitos farmacológicos, como agente cardiotônico, antioxidante, hipolipidêmico, anti-inflamatório, sedativo, entre outros. Considerando a importância da planta C. oxyacantha como medicamento alternativo natural e a inexistência de estudos envolvendo a toxicidade celular da mesma; o presente estudo teve como objetivo analisar os efeitos morfo-histológicos do extrato de frutos de C. oxyacantha em três grupos de tratamento I (50mg/Kg), II (100 mg/Kg), e III (200 mg/Kg) em células do fígado e baço de camundongos, a fim de avaliar os efeitos citotóxicos do extrato. O fígado dos indivíduos do grupo I não apresentou dano. Os indivíduos do grupo II apresentaram fígado em estágios iniciais de desorganização tissular e citoplasática. Já aqueles do grupo III sofreram maiores alterações histológicas como extensa desorganização citoplasmática, surgimento de vacúolos e capilares sinusóides aumentados e grande quantidade de célula... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Although modern medicine is well developed, according to the World Health Organization, about 75 to 95% of the population uses tradicional medicine to relieve some unpleasant symptoms. The major concern is that even medicinal plants being heavily used, there is no complete knowledge about their action in the body. The plant Crataegus oxyacantha, also known as white hawthorn or Hawthorn, is native to Europe, North America and Asia, was taken to other continents and has been widely used due to its potential pharmacological effects, such as cardiotonic, antioxidant, hypolipidemic, anti-inflammatory, sedative, among others. Considering the importance of the C. oxyacantha plant as a natural alternative medicine and the lack of studies involving its cellular toxicity; the objective of this study was to analyze the morpho-histological effects of C. oxyacantha fruit extract in three treatment groups I (50 mg / kg), II (100 mg / kg) and III (200 mg / kg) in liver and spleen cells of mice, in order to evaluate the cytotoxic effects of the extract. The liver of the individuals in group I showed no damage. Individuals in group II presented liver in the early stages of tissue and cytoplasmic disorganization. Already those of group III suffered major histological alterations such as extensive cytoplasmic disorganization, emergence of vacuoles and increased sinusoidal capillaries and large amount of Kupffer cells. On the other hand, the spleen was not histologically modified after the treat... (Complete abstract click electronic access below) / Mestre
8

Investigação de potencial genotóxico e clastogênico/aneugênico do extrato de frutos de Crataegus oxyacantha análises in vitro /

Quadros, Ana Paula Oliveira de January 2016 (has links)
Orientador: Edson Luis Maistro / Resumo: Cerca de 11% dos medicamentos considerados essenciais pela OMS são derivados de plantas medicinais, daí a importância do desenvolvimento de testes científicos sobre essas plantas, avaliando, além do seu real potencial farmacológico, a genotoxicidade, mutagenicidade, antigenotoxicidade, citotoxicidade, dentre outros, para esclarecer se o uso de tais plantas por seres humanos é seguro. Crataegus oxyacantha é uma planta originalmente encontrada na Europa e, devido à suas potencialidades medicinais, já há muito tempo foi introduzida no continente sulamericano. Pertencente à família Rosaceae, a árvore forma, na primavera, cachos grandes de flores brancas ou rosas de fragrância agradável, que no outono se transformam em pequenos frutos vermelhos. A importância da C. oxyacantha se dá pela presença comprovada de flavonóides, que são conhecidos por sua ação antioxidante. Devido a inexistência na literatura de estudos investigando a toxicidade genética de C. oxyacantha para os seres humanos, o presente estudo foi elaborado visando avaliar se o extrato de frutos desta planta apresenta efeitos citotóxico, genotóxico e clastogênico/aneugênico em leucócitos humanos e células HepG2 em cultura, e mutagênico em cepas de Salmonella typhimurium (teste de Ames). Os resultados da análise de genotoxicidade mostraram que o extrato não apresentou efeitos genotóxicos nas concentrações de 2,5 e 5,0 µg/ml em ambos os tipos celulares analisados, no entanto, em concentrações acima de 10 µg/ml verificou-s... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: About 11% of medicines considered essential by WHO are derived from medicinal plants, being important to develop scientific tests on these plants, evaluating several aspects as its pharmacological potential, genotoxicity, mutagenicity, antigenotoxicity, cytotoxicity, among others, to clarify if the use of such plants is safe for humans. Crataegus oxyacantha is a plant originally found in Europe and due to its medicinal potential, was at long time introduced in the South American continent. Belonging to the Rosaceae family, the tree form in the spring, large bunches of white flowers and pleasant fragrance of roses, which in autumn turn into small red fruits. The importance of C. oxyacantha is attributed to the presence of flavonoids as constituents, which are known for their antioxidant activity. Considering the absence in the literature of studies investigating the genetic toxicity of C. oxyacantha to humans, this study was designed to evaluate if the fruits extract of this plant present a cytotoxic, genotoxic and clastogenic/aneugenic effects in cultured human HepG2 and leukocytes cells, and mutagenicity in Salmonella typhimurium strains (Ames test). The results of genotoxicity analysis evidenced that the extract showed no genotoxic effects at 2.5 and 5.0 ug/ml concentrations, in both cell types tested, however, at concentrations above of 10 ug/ml significant DNA damage was observed. The micronucleus test results showed that the concentrations above of 10 ug/ml also produced... (Complete abstract click electronic access below) / Mestre
9

The effect of Crataegus oxyacantha Ø on homocysteine levels in males

Joubert, Petrie 19 July 2012 (has links)
M.Tech. / Cardiovascular disease and its complications accounts for about half of all deaths worldwide. As conventional risk factors do not successfully explain all of these cases, homocysteine (Hey) appears to be a new and promising field to investigate as an accompanying risk factor for the development of cardiovascular disease (Stanger et al., 2004). Hyperhomocysteinaemia, or elevated Hey levels, have been shown to be directly linked to the development of cardiovascular disease (Wald and Morris, 2002). Crataegus oxyaeantha Mother Tincture (0) has been used over centuries for various cardiovascular disease conditions and is considered to have cardio-protective properties (Rose and Treadway, 1999), however its effect on homocysteine levels has not been researched. The atm of this double-blind placebo-controlled study was to determine the effect of homoeopathically prepared Crataegus oxyaeantha (J on Hey levels in males aged 25-35 years of age by measuring Hey levels in the blood over a three week period. Participants attended an initial consultation where the procedure of the research was discussed, a short medical history was taken, and a full cardiovascular examination together with vital signs was assessed. Thereafter a pathology laboratory (Lancet laboratories) measured Hey levels of the participants. Those participants that qualified for the study were divided into two groups of fifteen. The experimental group received a 25mL bottle of Crataegus oxyaeantha 0 and the placebo group received a 25mL bottle of alcohol identical in appearance and taste. Participants were informed not to make any substantial changes to their diet and lifestyle. After three weeks a second Hey test was completed and a follow up consultation was scheduled. Collected data was statistically analyzed and a Chi Square goodness of fit test was utilized to determine if there was any significant decrease in Hey levels in the participating individuals. Preliminary findings suggest that Crataegus oxyaeantha (J was not effective in reducing plasma Hey levels in adult males with Hey levels of 6.3 mmoVL and higher, however more research over an extended period of time is needed to confirm these findings.
10

The antioxidative and hypolipidemic activities of hawthorn fruit. / CUHK electronic theses & dissertations collection

January 2001 (has links)
by Zhang Ze Sheng. / "October 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 157-174). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Page generated in 0.1087 seconds