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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.
241

Statistical analysis of longitudinal data /

Kim, Yangjin, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 84-88). Also available on the Internet.
242

White noise : mass media, public awareness, and the HIV/AIDS epidemic in St. Petersburg, Russia

Rassokhina, Maria 04 April 2014 (has links)
As an epidemic in the increasingly image-conscious and media-driven twenty-first century, the course of HIV/AIDS has been shaped by both mass media's portrayal of the disease and public perception of it. Russia currently has the highest HIV infection rate outside of Sub-Saharan Africa. In St. Petersburg, HIV infection rates are continuing to rise---the primary mode of transmission is changing from Injection Drug Use (IDU) to heterosexual intercourse, and fastest growing age group of infected persons is 30-40. As the epidemic begins to spill over from IDUs and homosexual communities into the general population, new attitudes are arising within St. Petersburg society and mass media. This paper analyses the role of mass media in HIV/AIDS prevention campaigns around the world, before presenting the author's research on the effects of mass media presentations of HIV on the St. Petersburg population. Through a three-part research study involving in-depth interviews, qualitative surveys, and a media analysis, the author portrays the media landscape in St. Petersburg in 2013 with an eye towards resolving media agendas, government policies, and public attitudes. / text
243

A comparative assessment of different legal systems and its impact on HIV/AIDS responses: a learning point for HongKong in the unabated fight against HIV/AIDS

Lim, Wei Siang., 林煒翔. January 2012 (has links)
Aim. This paper reveals key considerations required to reform and enact public health legislation to reduce and maintain the low prevalence of Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) in Hong Kong Special Administrative Region (HKSAR), in light of the growing global transmission of the epidemic. Background. There are a total of 33.3 million people living with HIV/AIDS globally, with 2.7 million becoming newly infected in 2010. Despite an overall global decline in HIV incidence of 19%, the number of newly infected people still exceeds the amount of people placed on antiretroviral drugs. HKSAR experienced a 0.5% increase in incidence in 2011, with 438 new cases reported to the Department of Health. There are currently no protective or punitive laws either for or against people living with HIV/AIDS, Men who have sex with men (MSM), sex workers or injecting drug users in HKSAR. Additionally, HIV/AIDS is not reportable under the notifiable disease act. Methods. The data used was collected between 1983 and 2012 and researched using electronic databases: MEDLINE, Google Scholar and Web of Science. Results. Ten studies met the inclusion criteria. The themes identified from the literature are: (1) True prevalence not reflected due to unawareness of serostatus, (2) Low uptake of screening due to the fear of stigmatisation, discrimination and/or prosecution and (3) Protective laws encourage responsibility. The statistics of HIV/AIDS in HKSAR may not be reflective of the true prevalence given the current methods of data collection. Additionally, the legal system in HKSAR fails to protect against discrimination based on an individual’s sexual orientation, which can potentially exacerbate existing stigma and consequently fuel the HIV/AIDS epidemic in Hong Kong. Conclusion. The inclusion of HIV/AIDS under the notifiable disease act can provide a more accurate prevalence and incidence rate. It can also be used as a tool to evaluate ongoing prevention efforts. HIV/AIDS specific laws, with regard to transmission and exposure, are detrimental to public health efforts in managing the epidemic. Instead, protective laws, such as anti-discrimination laws and the furthering of women’s rights, would yield greater benefits. / published_or_final_version / Public Health / Master / Master of Public Health
244

Efficacy and mechanism of PD1-based DNA vaccines in enhancing HIV-1 Gag-specific immunity

Zhou, Jingying., 周京颖. January 2013 (has links)
Human immunodeficiency virus type 1 (HIV-1) has caused more than 70 million infections worldwide since its discovery, with half of the infected already died by the end of 2011 as a result of HIV-progression to acquired immunodeficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) is capable to extend the lifespan of HIV patients but economic burden and emergence of resistant HIV strains pose immediate problems in the care of HIV patients. Furthermore, HAART cannot clear virus. Therefore, tremendous efforts have tried to develop an effective HIV vaccine in the last thirty years but only partial efficacy (31%) was achieved in the recent Thai RV144 clinical trial. Hence, new vaccine and understanding the mechanism are required now and in the future. In this study, two novel DNA vaccine strategies that utilized programmed death-1 (PD-1) or its isoform to improve immunogenicity of DNA vaccine for HIV-1 Gag p24 by acting on dendritic cells are described. The molecule PD-1 delivers negative regulatory signals to T cells through interacting with its ligands PD-L1 and PD-L2, while blocking this signal could functionally rescue the “exhausted” T cells during chronic infection such as HIV-1. The first DNA vaccine involves the fusion between HIV-1 Gag p24 antigen and soluble PD1 for effective targeting to DCs while improving antigen uptake and DC maturation, which in turn elicited consistently high frequencies of HIV-1 Gag-specific, broadly reactive, polyfunctional, long-lived and cytotoxic CD8+ T cells, in addition to robust anti-Gag antibody titers in mouse. The mechanism behind the action of this vaccine (sPD1-p24fc) is based on engagement of cross-presentation to CD8+ T cells, and induction of Th1 cytokines. The second DNA vaccine utilized a novel isoform of human PD1 (Δ42PD1) that contains a 42-nucleotide in-frame deletion located at exon 2 domain discovered in healthy PBMC donors. Interestingly, Δ42PD1 does not engage PD-L1/PD-L2 but its recombinant form could induce pro-inflammatory cytokines. When Δ42PD1 was used as an intramolecular adjuvant to develop a fusion DNA vaccine with HIV-1 Gag p24 antigen (sΔ42PD1-p24fc), enhanced DC uptake was also observed. When mice was vaccinated with this vaccine, significantly enhanced anti-p24 IgG1/IgG2a antibody, p24-specific T cells responses with functionally improved proliferative and cytolytic capacities were also identified. Importantly, both of these vaccines enhanced antigen-specific immunity and provided protection against pathogenic viral challenge as well as tumor growth in mice. Overall, the induction of high frequency of durable and protective Gag-specific T cell immunity, especially CD8+ T cell immunity using these two vaccines have important implications for vaccine development and immunotherapy against HIV-1 and other pathogens. / published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy
245

Identification of non-HIV-derived (poly)peptides as primary immunogens for HIV-1 vaccine development and localization of two dominant ADCC epitopes on hemagglutinin antigen of pandemic H1N1 influenza virus

Yang, Zheng, 楊爭 January 2014 (has links)
Development of effective vaccines against mutable viruses (i.e HIV-1 and influenza) remains a big challenge. Antibody-dependent cell-mediated cytotoxicity (ADCC) has been found to be a key component of immune protection against viral infections in vivo. Therefore, vaccine immunogens that elicit broadly neutralizing antibodies with high ADCC are desired for vaccine development. This study is to identify primary immunogens that can initiate somatic maturation of germline antibodies of known broadly neutralizing HIV-1 antibodies (bnAbs) for HIV vaccine development and to localize dominant ADCC epitopes on hemagglutinin (HA) of pandemic H1N1 influenza virus for development of a flu vaccine. Based on the observations that known HIV-1 bnAbs have extensive somatic mutation compared to their germline versions and that HIV-1 envelope (Env) glycoprotein lacks measurable binding to putative germline antibodies of known bnAbs, we hypothesized that non-HIV-derived (poly)peptides may serve as primary immunogens to trigger somatic maturation of germline antibodies of bnAbs, leading to elicitation of intermediate antibodies (iAbs) that can further mature to HIV-1 bnAbs upon Env vaccination or HIV-1 infection. Using b12 as a model bnAb, we identified five non-HIV-derived (poly)peptides that bound to putative b12 germline and iAbs, and immunized rabbits with the (poly)peptide priming followed by Env boosting. Rabbit immunization with (poly)peptides alone induced high titers of antibodies that were cross-reactive with gp140SF162 trimer and resurfaced Env RSC3, and the serum IgGs neutralized SF162 and JRFL. These results suggest that the (poly)peptides might structurally mimic CD4bs of Env. Priming rabbits with (poly)peptides followed by boosts with gp140SF162 and RSC3 resulted in antibodies capable of competing with b12 for binding to gp140SF162 trimer and neutralizing cross-clade isolates, while control rabbits without priming produced antibodies that were unable to compete with b12 for gp140SF162 trimer binding, and the serum IgGs neutralized only 3 clade B isolates. Our results provide proof of concept that non-HIV-derived (poly)peptides may serve as primary vaccine immunogens to initiate guided immune responses towards bnAbs. HA protein has high level of immunogenicity and considered the most important target for immune protection against influenza virus infection. Several potent HA-specific bnAbs have been reported with their conserved neutralizing epitopes revealed, but there has been no report so far about ADCC epitopes on HA. Using yeast display and flow cytometry assisted cell sorting, we mapped the epitope of convalescent plasma IgGs with different ADCC activity, we identified two dominant ADCC epitopes, designated HA-E1 [AA92-117] and HA-E2 (AA 124-159), on HA of 2009 pandemic H1N1 influenza virus. E1 and E2 overlapped with the immunodominant epitopes of HA. Depletion of purified patient plasma IgGs with yeast cells expressing E1 or E2 peptides decreased ADCC activity of the IgGs. E1 and E2 sequences are highly conserved in H1N1 strains, but less so in other subtypes of influenza A viruses. Our study may aid in designing immunogens that can elicit antibodies with high ADCC activity. Vaccine immunogens designed to include the structural determinants of potent bnAbs and ADCC epitopes may confer a comprehensive immune protection against influenza virus infection. / published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy
246

Health risk Escherichia coli O157:H7 in drinking water and meat and meat products and vegetables to diarrhoeic confrimed and non-confirmed HIV/AIDS patience

Obongo, BO, Momba, MNB, Rodda, N January 2008 (has links)
The current study explored the health risk of E. coli O157:H7 to diarrhoeic confrimed and non-confirmed HIV/AIDS patients due to their exposure to presumed ingestion of water, meat, meat products and vegetables ostensibly contaminated with E. coli O157:H7. Strains of E. coli O157:H7 were isolated by enrichment culture and on Cefixime-Telurite Sorbitol MacConkey agar. Average counts of presumptive E. coli O157 were used for dose-response assessment.Probability of infection to confrimed and non-confirmedHIV/AIDS patients was 20 and 27 % from meat and meat products, 21% and 15% from vegetables and 100% due to ingestion of 1500ml person day of water. Drinking water had higher probability of transmitting E. coli O157 :H infections than meat and meat products and vegetables.Prabability of E coli O157:H7 infections were high for confrimed HIV/AIDS patients than for non-confirmed patients. Water and foods consumed by HIV/AIDS patients should be safe of any microbial contaminants, these waters and foods should as well be investigated for other enteric pathogens to establish their safety.
247

Scope and frequency of enteric bacterial pathogens isolated from HIV/AIDS patients and their household drinking water in Limpopo Province

Obi, CL, Ramalivhana,J, Igumbor, J, Momba, MNB 13 July 2007 (has links)
Although HIV/AIDS and water-borne infections, exemplified by diarrhoea, are leading causes of morbidity and mortality in developing countries, their association has received only cursory attention. This study was therefore conducted to ascertain the scope and frequency of potential enteric bacterial pathogens isolated from stool samples of HIV-positive and -negative individuals with and without diarrhoea as well as household drinking water of the study groups in rural communities in Limpopo Province. A prospective study involving 330 HIV-positive individuals (200 with diarrhoea and 130 without diarrhoea) and 160 HIV-negative patients, (80 with diarrhoea and 80 without) was undertaken from August 2005 to January 2006. Stool and drinking water samples were analyzed for the presence of enteric bacterial pathogens using standard microbiological methods. Of the 330 HIV-positive individuals, 126 (38%) and 206 (62%) were males and females respectively. HIV prevalence was mostly common in the age group 21to 30 years. A potential enteric pathogen was isolated from all (100%) of the HIV-positive individuals with diarrhoea and 68 (52.3%) without diarrhoea (P = 0.0001). Bacteria that were significantly associated with diarrhoea among HIV-positive patients and their household drinking water were Escherichia coli, Salmonella spp., Campylobacter spp., Shigella spp. and Aeromonas spp. whereas Plesiomonas shigelloides was not. The same profiles of enteric bacterial pathogens were isolated from HIV-negative individuals but at lower frequencies (P = 0.0001). Enteric pathogens were distributed across gender and different age strata. A notable finding was the emergence of Aeromonas spp. and Plesiomonas shigelloides in HIV infected individuals with diarrhoea. This study provides the foremost baseline reference compendium on the scope and frequencies of enteric bacterial pathogens isolated from stool and household drinking water samples of HIV-positive and -negative individuals with and without diarrhoea in rural communities in the Limpopo Province.
248

Mother to child transmission of HIV : maternal and child characteristics

Luo, Chewe Angela January 2000 (has links)
A prospective study at the University Teaching Hospital of 306 women with their infants, who were enrolled at delivery, was conducted in 1997. The primary aim was to define the magnitude and effects of maternal human immuno-deficiency virus (HIV) infection on obstetric problems and infant outcome. Women were mainly over 19 years (87.3%), literate (73.7%) and married (91.4%), with no formal income (75.7%). 48.2% and 46.7% had antenatal or post-partum anaemia (PPA) and of these 1.8% and 6.2% were severely anaemic. Low post-partum (PP) serum retinol «0.7f.lmoI/L) and CD4 counts «400 cells/mm3 ) occurred in 12.8% and 16.2% of the women. The commonest obstetric problems were previous child death (32.4%), malaria treatment during pregnancy (32.6%), previous abortion (16.4%) and hypertension (13.7%). Post-partum, 30.1% of the women were HIV infected, 14.9% rapid plasma reagin (RPR) positive and 4.5% hepatitis B surface antigen (HBsAg) positive. Factors independently associated with HIV infection were: alcohol intake during pregnancy (RR 5.67); ante-partum haemorrhage (RR 5.85); PP HBsAg positivity (RR 27.45); low PP CD4 cell count (RR 10.63) and PPA (RR 3.99). Primigravidae had a lower risk ofHIV infection (RR OJ). For PPA independent risk factors were: caesarean section (RR 9.95); HIV infection (RR 2.81) and low PP mean corpuscular haemoglobin concentration (MCHC) (RR 8.33); mean corpuscular volume (MCV) (RR 2.39) and serum retinol (RR 3.03). Alcohol intake during pregnancy (RR 0.22) and low PP maternal weight (RR 0.10) were associated with reduced risk ofPPA. The prevalence of low birth weight (LBW; weight <2.5kg), pre-term delivery «37 weeks gestation) and intra-uterine growth retardation (IUGR; weight < lOth centile for gestational age) were 18.9%, 23.8% and 25.9%. These showed no association with maternal HIV infection although the mean birth weight was significantly lower in children born of HIV infected mothers (P=0.006). In HN non-infected women, antenatal anaemia was independently associated with increased risk pre-term delivery (RR 5.l2) and low birth weight (RR 5.08). Low PP serum retinol increased the risk of IUGR (RR 3.10). In HN infected women, lack of paternal income was associated with pre-term delivery (RR 11.7), IUGR with LBW (RR 3.59) and antibiotic treatment in pregnancy with IUGR (RR 5.85). The cumulative rate of HN mother to child transmission (MTCT) at 1 year of age was 31 %, with 10.3%, 1O.l% and 9.l% of infants DNA polymerase chain reaction (PCR) positive at birth, 1 month and 4 to 12 months respectively. On multivariate analysis, PP maternal viral load (>50,OOOcopies Iml) was the only risk factor associated with early infant HN acquisition (birth and 1 month) (P = 0.005) and cumulative infections at one year (P=O.OOI). At a year of age, HIV infected children were severely undernourished (weight for age median Z-score -3.46) and stunted (height for age median Z-score -4.44). Stunting was the main form of malnutrition in uninfected infants regardless of maternal HN status. Reported morbidity in infancy was unaffected by HN status. The infant mortality rate was 136 per 1000 live births, 85 per 1000 in HN uninfected children of uninfected mothers, 272 per 1000 in infants of infected mothers and 424 per 1000 in infected infants. After correcting for confounders, maternal HN infection (HR 0.28) and primigravidae (HR 0.20) were significant risk factors for infant survival. The population attributable risk percentage of infant mortality was 41.3% for maternal HN infection and 24.9% when the infant was HN infected as well.
249

Stigma : the negatives of being HIV positive

Burke, Christina Michelle 02 February 2012 (has links)
This report addresses the issue of stigma surrounding people living with the human immunodeficiency virus and the acquired immunodeficiency syndrome or HIV/AIDS. It examines the relationship between the disease and a person’s willingness to seek treatment and how an HIV diagnosis affects self-acceptance, family relationships, friendships and well being of people living with HIV/AIDS. In many cases the self-imposed stigma is just as menacing as external stigma. The global pandemic of HIV/AIDS affects every class, color and creed. It is a public health crisis that quietly infects new victims daily. In the thirty years since its discovery there is still no known cure. The passage of the Ryan White act was the federal government’s first official response to the issue. While the disease is manageable for many who can afford expensive anti-retroviral medication, the side effects and psychological turmoil they face is oftentimes unbearable. This report, and the accompanying video, Stigma, which can be found at http://christinaburkephoto.blogspot.com/ examines the social and psychological effects on people living with HIV/AIDS. / text
250

A descriptive study of the impact Aniz, incorporated has on the battle against HiV/AIDS in the Atlanta, Georgia area

Graves, Eric L, Sr 01 May 2010 (has links)
This is a descriptive study of the impact that Aniz, Incorporated has had on the battle against HIV/AIDS in the inner city of Atlanta, Georgia. It examines the relationships among an individual’s drug of choice and a person’s failure to protect him or herself from the disease; an individual’s mode of infection and a person’s income level; an individual’s type of insurance and a patient’s T-cell count. The results of the study suggest that there is no statistically significant relationship between a drug of choice and a person’s failure to protect him or herself, there is also no statistically significant relationship between an individual’s mode of infection and a person’s individual income, but there is a statistically significant relationship among types of insurance and an individual’s T-cell count. These findings were based on a .05 level of probability between the variables. This study and others like it will assist Aniz, Incorporated and could assist other nongovernmental agencies to better target their services and programs to better meet the needs of the demographic groups being served.

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