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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.
91

Paukščių hemosporidinių parazitų (Haemosporida) morfologinė ir genetinė įvairovė bei specifiškumas nedidelėse Bulgarijos (Brodilovo) ir Rusijos (Kuršių nerijos) teritorijose / Morphological and genetic diversity and specific particularities of bird haemosporidian parasites (Haemosporida) in two selected areas of  Bulgaria (Brodilovo) and Russia (Curonian Spit)

Prontkelevičiūtė, Živilė 07 August 2012 (has links)
Siekiant išsiaiškinti paukščių hemosporidijų rūšinę sudėtį, genetinę įvairovę ir paplitimą bei specifiškumą nedidelėse Bulgarijos (Brodilovo) ir Rusijos (Kuršių nerija) teritorijose, buvo ištirta 50 rūšių žvirblinių (Passeriformes) būrio paukščių, priklausančių 16 šeimų. Paukščių gaudymui buvo naudojami voratinkliniai tinklai ir stacionariosios gaudyklės. Medžiaga buvo renkama ne didesniu nei 20 km spinduliu. Medžiaga buvo tiriama tradiciniais parazitologiniais (mikroskopavimas) ir šiuolaikiniais molekuliniais (PGR, sekvenavimas, filogenetinės analizės sudarymas specialių programų pagalba) metodais. Bulgarijoje identifikuota 10 hemosporidijų rūšių, priklausančių Haemoproteus, Plasmodium ir Leucocytozoon gentims; Kuršių nerijoje nustatyta 11 hemosporidijų rūšių, priklausančių toms pačioms gentims. Bulgarijoje nustatytas žymiai didesnis užsikrėtimo L. sp. parazitais ekstensyvumas. Nustatyta, jog Bulgarijoje iš 28 identifikuotų parazitų genetinių linijų, 20-ties linijų transmisija vyksta šioje teritorijoje, Kuršių nerijoje iš 50 linijų vietinė transmisija vyksta tik 7 rūšių. Išaiškinta, kad hemosporidijos mažiau specifiškos stuburiniam šeimininkui Kuršių nerijoje. Pasitelkus programos MEGA 5.0.5 versiją, nubraižyti filogenetiniai medžiai, atspindintys nustatytų parazitų filogenetinius ryšius. / The aim was to find out what haemosporidian parasites are common in the birds of order Passeriformes in certain teritories of Europe, what are particularities of their disstribution and specificity, data were collected in two selected areas of Bulgaria (Brodilovo) and Russia (Curonian spit). Traditional (microscopy) and modern (PCR, DNA sequencing, construction of phylogenetic trees) methods were used for investigation. The birds were captured by mist nets and large „Rybachyj“ tipe trap. There were collected 50 species of birds, refering to 16 families. The material was collected in areas which do not exceed 20 km. 10 species of Haemoproteus, Plasmodium and Leucocytozoon in Bulgaria were detected. 11 species of the same genus parasites were identified in Russia. High intensity of Leucocytozoon parasitaemia in Bulgaria was detected, while in Russia it was very low. The investigation showed that local transmission of 20 (out of 28 identified) genetic lines of parasites take place in Bulgaria and in Curonian spit only 7 (out of 50 identified) genetic lines are transsmited localy. It was cleared out that haemosporidians are less specific to vertebrate host in Curonian spit. Phylogenetic trees were constructed to ascertain which genetic lines are related with phylogenetic traits.
92

The Impact of Efficacious Treatments for Major Depressive Disorder on Remission Rates of Specific Symptoms: A Re-Analysis of the Treatment of Depression Collaborative Research Program

Stewart, JEREMY 03 September 2009 (has links)
Major Depressive Disorder (MDD) is a highly prevalent mental disorder that will affect 12.2% of Canadians over the course of their lifetimes, and 4.8% annually (Patten, et al., 2006). One of the most robust findings in the MDD literature is that the gold-standard treatments – Cognitive-Behavioral Therapy (CBT), Interpersonal Psychotherapy (IPT), and anti-depressant medications - are equal in their efficacy, and superior to placebo. However, it is unclear whether rates of remission for certain types of symptoms differ among treatments with theoretically different mechanisms. This study re-analyzed data from the Treatment of Depression Collaborative Research Program, which included 158 adults with MDD randomized to CBT, IPT, imipramine or placebo. We statistically derived 4 factors from the baseline Hamilton Depression Rating Scale. We hypothesized that the rate of remission of somatic factors (sleep and appetite) would be most rapid in the group receiving imipramine plus clinical management (IMI-CM), and that the rate of remission for cognitive-affective factors would be fastest in IPT and CBT. Hierarchical regression analyses predicted the sum of symptom scores corresponding to each factor using linear and quadratic time (measured in weeks). Treatment-by-time interactions were entered in a stepwise fashion. There were no significant interactions found in the appetite factor, suggesting that all therapies acted on these symptoms at similar rates. Consistent with hypotheses, IMI-CM produced more rapid remission in sleep symptoms compared to psychotherapy. Surprisingly, IMI-CM was also more rapid at relieving cognitive-affective symptoms. The results lend partial support to the idea that different treatments for MDD may target specific symptoms at different rates according to their underlying mechanisms of action. The findings present some exciting possibilities for elevating response rates through empirically-based “tailored treatments”. / Thesis (Master, Psychology) -- Queen's University, 2009-09-03 14:41:46.163
93

CATEGORY-SPECIFICITY OF WOMEN’S SEXUAL AROUSAL ACROSS THE MENSTRUAL CYCLE

BOSSIO, JENNIFER 07 October 2011 (has links)
Unlike men, women’s genital arousal is category-nonspecific with respect to sexual orientation, such that their genital responses do not differentiate stimuli by gender. A possible explanation for women’s nonspecific sexual response is the inclusion of women at different phases of the menstrual cycle or women using hormonal contraceptives in sexual psychophysiology research, which may be obscuring a specificity effect. The present study employs the ovulatory-shift hypothesis – used to explain a shift in women’s preferences for masculine traits during peak fertility – as an explanatory model for women’s nonspecific sexual arousal. Twenty-nine naturally-cycling women were tested at two points in their menstrual cycles (follicular and luteal) to determine the role of hormonal variation, as estimated by fertility status, on the specificity of genital (using vaginal photoplethysmograph) and subjective sexual arousal. Cycle phase at the time of first testing was counterbalanced; however, no effect of order was observed. Inconsistent with the ovulatory-shift model, the predicted mid-cycle shift in preferences for masculinity or sexual activity at peak fertility was not obtained. Category-specificity of genital arousal did not increase during the follicular phase. A statistical trend was observed for higher genital arousal to couple sex stimuli during the follicular phase compared to the luteal phase, suggesting that women’s genital arousal may be sensitive to fertility status with respect to sexual activity (specifically, couple sex), but not gender. Subjective arousal was not influenced by fertility status. This study is the first to provide evidence that women’s genital arousal may be influenced by the probability of conception. / Thesis (Master, Psychology) -- Queen's University, 2011-09-29 08:51:26.973
94

Genetic diversity and host specificity in the winter tick - Dermacentor albipictus (Acari: Ixodidae)

Leo, Sarah S. T. Unknown Date
No description available.
95

Specificity and Economic Performance

Minagawa, Tadashi, Yoneda, Koji 12 1900 (has links)
No description available.
96

A Phage Display System to Profile the DNA-binding Specificities of C2H2 Zinc Fingers

Lam, Kathy 07 January 2011 (has links)
Knowing the sequence specificities of transcription factors allows us to surmise their functions and establish their regulatory roles in genomes. The most common DNA-binding domain among eukaryotic transcription factors is the Cys2His2 zinc finger domain; however, despite their prevalence, the specificities of the majority of Cys2His2 zinc finger proteins remain unknown due to the difficulty in assaying them. My objective was to develop a new phage displayed-based assay, in which individual Cys2His2 domains are displayed on phage in an otherwise constant three-finger protein scaffold. In Chapter 2, I discuss evidence for the modularity of the Cys2His2 domain, since my assay requires that zinc fingers be modular. In Chapter 3, I describe my results on the development of this phage display-based assay. This work provides support for a new strategy to determine the specificities of individual zinc fingers, which can be used to infer specificities for multi-finger Cys2His2 proteins.
97

A Phage Display System to Profile the DNA-binding Specificities of C2H2 Zinc Fingers

Lam, Kathy 07 January 2011 (has links)
Knowing the sequence specificities of transcription factors allows us to surmise their functions and establish their regulatory roles in genomes. The most common DNA-binding domain among eukaryotic transcription factors is the Cys2His2 zinc finger domain; however, despite their prevalence, the specificities of the majority of Cys2His2 zinc finger proteins remain unknown due to the difficulty in assaying them. My objective was to develop a new phage displayed-based assay, in which individual Cys2His2 domains are displayed on phage in an otherwise constant three-finger protein scaffold. In Chapter 2, I discuss evidence for the modularity of the Cys2His2 domain, since my assay requires that zinc fingers be modular. In Chapter 3, I describe my results on the development of this phage display-based assay. This work provides support for a new strategy to determine the specificities of individual zinc fingers, which can be used to infer specificities for multi-finger Cys2His2 proteins.
98

Mechanisms of Action of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) in Colon Cancer

Pathi, Satya 2012 August 1900 (has links)
Non-steroidal anti-inflammatory drugs (NSAIDs) and their NO derivatives (NO-NSAIDs), and synthetic analogs are highly effective as anticancer agents that exhibit relatively low toxicity compared to most clinically used drugs. However, the mechanisms of action for NSAIDs and NO-NSAIDs are not well defined and this has restricted their clinical applications and applications for combined therapies. Earlier studies from our laboratory reported that specificity protein (Sp) transcription factors (Sp1, Sp3 and Sp4) are overexpressed in several types of human cancers including colon cancer and many Sp-regulated genes are pro-oncogenic and individual targets for cancer chemotherapy. Based on published results showing that NSAIDs downregulate several putative Sp-regulated genes, we hypothesized that the anticancer properties of NSAIDs may be due, in part, to downregulation of Sp transcription factors. NSAIDs including aspirin and tolfenamic acid (TA) and nitro derivatives of NSAIDs such as GT-094 have been investigated in colon cancer cells and in vivo xenograft models. Aspirin and TA induced apoptosis and decreased colon cancer cell growth and tumor growth in vivo and downregulated genes associated with cell growth, survival, and angiogenesis. Previous RNA interference studies in this laboratory have shown that many of these genes are regulated, in part, by Sp transcription factors Sp1, Sp3 and Sp4 that are overexpressed in colon and other cancer cell lines. Not surprisingly, these NSAIDs also decreased Sp1, Sp3 and Sp4 proteins and Sp-regulated gene products in colon cancer cells and this was due to caspase-dependent proteolysis of Sp1, Sp3 and Sp4 proteins. Aspirin-induced activation of caspases and degradation of Sp1, Sp3 and Sp4 was due to sequestration of zinc and could be reversed by addition of zinc sulphate, whereas TA mediated induction of caspases was independent of zinc ions and is currently being investigated. GT-094 is a novel NO chimera-containing NSAID, which also inhibited colon cancer cell proliferation and induced apoptosis; these effects were accompanied by decreased mitochondrial membrane potential (MMP) and induction of reactive oxygen species (ROS), and were reversed after cotreatment with the antioxidant glutathione. GT-094 also downregulated Sp and Sp-dependent gene products and was due to decreased expression of microRNA-27a (miR-27a) and induction of ZBTB10, an Sp transcriptional repressor that is regulated by miR-27a in colon cancer cells. Moreover, the effects of GT-094 on Sp1, Sp3, Sp4, miR-27a and ZBTB10 were also inhibited by glutathione suggesting that the anticancer activity of GT-094 in colon cancer cells is due, in part, to ROS-dependent disruption of miR-27a:ZBTB10. The importance of ROS induction in targeting Sp transcription factors was also confirmed using pro-oxidants such as ascorbic acid, hydrogen peroxide and t-butyl hydroperoxide and similar results have been observed in collaborative studies with other ROS inducers in colon cancer cells. Many cancer cell lines and tumors exhibit addiction to non-oncogenes such as Sp1, Sp3 and Sp4 for maintaining the oncogenic phenotype and future research will focus on the mechanisms of ROS-mediated targeting of Sp transcription factors which represents a novel approach for cancer chemotherapy.
99

Kudoid parasites: species definition and specificities

Mieke Burger Unknown Date (has links)
Kudoid parasites are common in marine fish and their affects range from relatively benign to pathogenic. They are notorious in the seafood industry for spoiling fish meat, either by muscle liquefaction or by producing unsightly macroscopic cysts. Kudoids also infect several other tissues such as brain, heart, gills, connective tissue, intestinal smooth muscle, and epithelia. Since the revised classification of the Kudoidae in 2004, kudoid myxospores have a range of shapes, but with two main characteristics: they have four or more spore valves with the equivalent number of polar capsules. With relatively few morphological traits to base kudoid species descriptions, DNA has proven to be increasingly useful to specifically diagnose infections. However, to properly utilise genetic information, there is a need to understand how genetics relates to the biological characteristics of species. This will ensure the genetic markers used are appropriate for species characterisation. This project aimed to develop an understanding of how biological characteristics including morphology, tissue tropism, host specificity, and geographic distribution correlate with genetic relatedness of kudoid species, and how this information could be employed to facilitate diagnosis and characterisation of species. A taxonomic investigation of kudoid isolates, mostly from the east coast of Queensland, Australia, was conducted using information on host identity, locality, infection status, tissue of infection and histological response to infection. Together with spore morphology and DNA relationships, comparisons were made with existing data from literature. Forty-three small subunit and 68 large subunit ribosomal DNA sequences were generated from kudoid isolates for this project. The two gene regions showed similar relationships amongst the kudoids, however the genetic variability between closely related species was less conserved in the large subunit, and showed superior species resolution that correlated with subtle morphological differences of spores. Broadly speaking, genetic relatedness of kudoids is closest for species infecting the same type of tissue with similar spore morphology. Within these tissue/morphology groups, some relationships were emerging from genetic correlations with pathology, however there are weaknesses in utilising this characteristic since pathology may change with host species or host age. Similar relationships to pathology were seen from geographic locality; however, the limited number of areas that genetic data originates from may have introduced some bias. Lastly, there were very few genetic relationships that correlated with host relatedness. The taxonomic affinities of the new kudoid isolates lead to the characterisation of six novel kudoid species and four additional host-parasite combinations. The investigation into these new species highlighted the broad host ranges and geographic distribution of some kudoid species. Genetic mixing of kudoid species populations from the east coast of Queensland, Australia with Japan was noted. For example, Kudoa amamiensis was discovered from carangid and pomacentrid fish from Queensland, increasing the host range from eight (seven from Japan, one from north Queensland) to 11 host species. Also, geographic distribution was extended to Heron Island on the south Great Barrier Reef (Queensland). The distribution did not extend to rocky temperate reefs further south. Another example is Kudoa yasunagai which was previously recorded from four fish species in Japan and one from the Philippines. Now the distribution has been extended to North Stradbroke Island in Southern Queensland from three additional host species. The connection was made between these host isolates with the assistance of DNA and a novel way of analysing morphological data in species that have variable morphotypes i.e. different numbers of polar capsules in the spores. It was confirmed that the dominant morphotype can vary between different hosts and even host samples of the one species. Genetic data has also proven useful in the determination of host range. An analysis of kudoid host specificity showed just over two thirds of the described kudoid species have been recorded from a single host; the remainder have been recorded from two to 38 host species. By using DNA data, 17 new hosts were recorded for K. thalassomi (total 18 hosts). The new hosts came from six different host families, but these fish shared the same habitat on the Great Barrier Reef. Other high host range kudoid species may be disproportionately broad as similar morphological species may have been misidentified from some hosts. For example, the host range of K. thyrsites (38) is likely to represent a species complex that may be split pending further genetic analyses. From this study, it has been reinforced that a holistic approach to species definition is important. Genetic analysis has become a particularly valuable tool; however, in conjunction with biological data such as spore morphology, pathology, host range, and geographic distribution, our understanding of kudoid parasites becomes more robust and provides important knowledge for diagnostics and aquaculture management. In the future, significant improvements in kudoid understanding will coincide with the solving of kudoid life cycles and transmission patterns.
100

Alterations in activity and specificity of intracellular proteolysis in disease pathogenesis /

Lu, Lei. January 2005 (has links)
Lic.-avh. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 3 uppsatser.

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