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排序方式: 共有3215条查询结果,搜索用时 15 毫秒
31.
Laura Koopman Lea G. Donselaar Jany J. Rademakers Michelle Hendriks 《Journal of clinical epidemiology》2013,66(3):340-348
ObjectiveTo find ways to improve response rates of medical and health surveys. We investigated whether a prenotification letter instead of a second reminder and varying senders of the questionnaires would affect response rates.Study Design and SettingWe present the results of two studies. In the first study, four groups were compared that either received a prenotification letter (group 1 and 2) or a second reminder letter (group 3 and 4); received the questionnaire from either a research institute (group 1 and 3) or a health insurance company (HIC; group 2 and 4). In the second study, we compared two groups that received the questionnaire sent by either a HIC or a hospital. Response rates, response speed, respondent characteristics, item nonresponse, and mean scores on quality aspects and global ratings were compared.ResultsResponse rates did not differ significantly between groups. Prenotification groups returned their questionnaires faster. No other significant differences were found for response speed, respondent characteristics, item nonresponse, or mean scores.ConclusionA prenotification letter does only increase initial response speed and does not increase total response rates. A prenotification letter should be considered when quick response is desirable. Varying senders had no effect on response rates. 相似文献
32.
Toby Lea Limin Mao Nicky Bath Garrett Prestage Iryna Zablotska John de Wit Martin Holt 《AIDS and behavior》2013,17(4):1344-1351
Injecting drug use is commonly reported among gay and bisexual men in Australia. We examined the prevalence and covariates of injecting drug use among men participating in the Sydney Gay Community Periodic Survey between 2004–06 and 2011. In 2004–06, data was collected about which drugs were injected, while in 2011, data was collected about hepatitis C (HCV) and esoteric sexual practices. In 2004–06, 5.6 % of men reported injecting drugs in the previous 6 months; 3.4 % reported methamphetamine injection and 0.4 % heroin injection. In 2011, men who injected drugs were less likely to be employed full-time, and more likely to be HCV-positive, HIV-positive, to have used party drugs for sex, and to have engaged in esoteric sexual practices. The strong associations between injecting drug use, sexual risk practices and blood-borne virus infection suggests the need for combined sexual health and harm reduction services for gay and bisexual men who inject drugs. 相似文献
33.
34.
José Alexandre da Rocha Curvelo Anna Lea Silva Barreto Camila A. dos Anjos Rafaela S. Santana Ariadne Nunes Alonso Maria Teresa Vilela Romanos Kelly C. G. de Moura Paula Fernandes Carneiro Maristela Barbosa Portela Maria do Carmo F. R. Pinto Rosangela Maria de Araújo Soares 《Medicinal chemistry research》2015,24(3):1155-1161
35.
Galectina-3 Associada a Formas Graves e Mortalidade em Longo Prazo em Pacientes com Doença de Chagas
Fbio Fernandes Carlos Henrique Valente Moreira Lea Campos Oliveira Marcela Souza-Basqueira Barbara Maria Ianni Claudia di Lorenzo Felix Jos Alvarez Ramires Luciano Nastari Edecio Cunha-Neto Antonio L. Ribeiro Renato Delascio Lopes Sheila M. Keating Ester Cerdeira Sabino Charles Mady 《Arquivos brasileiros de cardiologia》2021,116(2):248
Background The histopathological characteristics of Chagas disease (ChD) are: presence of myocarditis, destruction of heart fibers, and myocardial fibrosis. Galectin-3 (Gal-3) is a biomarker involved in the mechanism of fibrosis and inflammation that may be useful for risk stratification of individuals with ChD.Objectives We sought to evaluate whether high Gal-3 levels are associated with severe forms of Chagas cardiomyopathy (CC) and whether they are predictive of mortality.Methods We studied anti-T. cruzi positive blood donors (BD): Non-CC-BD (187 BD without CC with normal electrocardiogram [ECG] and left ventricular ejection fraction [LVEF]); CC-Non-Dys-BD (46 BD with CC with abnormal ECG but normal LVEF); and 153 matched serum-negative controls. This cohort was composed of 97 patients with severe CC (CC-Dys). We used Kruskall-Wallis and Spearman’s correlation to test hypothesis of associations, assuming a two-tailed p<0.05 as significant.Results The Gal-3 level was 12.3 ng/mL for Non-CC-BD, 12.0 ng/mL for CC-Non-Dys-BD, 13.8 ng/mL for controls, and 15.4 ng/mL for CC-Dys. LVEF<50 was associated with higher Gal-3 levels (p=0.0001). In our linear regression adjusted model, we found association between Gal-3 levels and echocardiogram parameters in T. cruzi-seropositive subjects. In CC-Dys patients, we found a significant association of higher Gal-3 levels (≥15.3 ng/mL) and subsequent death or heart transplantation in a 5-year follow-up (Hazard ratio – HR 3.11; 95%CI 1.21–8.04; p=0.019).Conclusions In ChD patients, higher Gal-3 levels were significantly associated with severe forms of the disease and more long-term mortality, which means it may be a useful means to identify high-risk patients. (Arq Bras Cardiol. 2021; 116(2):248-256) 相似文献
36.
Hansen Mads Kingo Guldberg Kjærgaard Kristoffer Eriksen Lotte Lindgreen Grønkjær Lea Ladegaard Mikkelsen Anne Catrine Daugaard Sandahl Thomas Damgaard Vilstrup Hendrik Thomsen Karen Louise Lauridsen Mette Munk Enok 《Metabolic brain disease》2022,37(3):589-605
Metabolic Brain Disease - Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically... 相似文献
37.
Melatonin suppresses NO-induced apoptosis via induction of Bcl-2 expression in PGT-beta immortalized pineal cells 总被引:2,自引:0,他引:2
Yoo YM Yim SV Kim SS Jang HY Lea HZ Hwang GC Kim JW Kim SA Lee HJ Kim CJ Chung JH Leem KH 《Journal of pineal research》2002,33(3):146-150
In the present study, we investigated whether melatonin would prevent nitric oxide (NO)-induced apoptotic death of PGT-beta immortalized pineal cells. To examine the protective effect of melatonin, cytotoxicity assay, DNA fragmentation analysis, caspase-3 activity assay, and Western blotting for caspase-3 and poly(ADP-ribose) polymerase (PARP) were performed. Treatment of cells with S-nitroso-N-acetylpenicillamine (SNAP), an NO donor, was shown to induce apoptotic cell death in a dose-dependent manner, and pretreatment with melatonin (0.1 mm) attenuated the occurrence of NO-induced apoptotic cell death. DNA fragmentation in response to NO was also arrested by melatonin. Caspase-3 activity induced by NO was decreased with melatonin treatment. Furthermore, the active fragments of caspase-3 and PARP were almost completely absent following exposure to melatonin. To elucidate the protective mechanisms of action of melatonin, Western blot analyses for Bcl-2 expression and cytochrome c release were carried out. Pretreatment with melatonin (0.1 mm) induced the expression of Bcl-2 and suppressed the release of cytochrome c into the cytosol, thereby arresting NO-induced apoptotic cell death. These results suggest that the antiapoptotic effect of melatonin is associated with induction of Bcl-2 expression in PGT-beta cells, which in turn blocks caspase-3 activation and inhibits cytochrome c release into the cytosol. 相似文献
38.
Beverley M Essue Merel Kimman Nina Svenstrup Katharina Lindevig Kjoege Tracey Lea Laba Maree L Hackett Stephen Jan 《Bulletin of the World Health Organization》2015,93(2):102-112B
Objective
To determine the nature, scope and effectiveness of interventions to reduce the household economic burden of illness or injury.Methods
We systematically reviewed reports published on or before 31 January 2014 that we found in the CENTRAL, CINAHL, Econlit, Embase, MEDLINE, PreMEDLINE and PsycINFO databases. We extracted data from prospective controlled trials and assessed the risk of bias. We narratively synthesized evidence.Findings
Nine of the 4330 studies checked met our inclusion criteria – seven had evaluated changes to existing health-insurance programmes and two had evaluated different modes of delivering information. The only interventions found to reduce out-of-pocket expenditure significantly were those that eliminated or substantially reduced co-payments for a given patient population. However, the reductions only represented marginal changes in the total expenditures of patients. We found no studies that had been effective in addressing broader household economic impacts – such as catastrophic health expenditure – in the disease populations investigated.Conclusion
In general, interventions designed to reduce the complex household economic burden of illness and injury appear to have had little impact on household economies. We only found a few relevant studies using rigorous study designs that were conducted in defined patient populations. The studies were limited in the range of interventions tested and they evaluated only a narrow range of household economic outcomes. There is a need for method development to advance the measurement of the household economic consequences of illness and injury and facilitate the development of innovative interventions to supplement the strategies based on health insurance. 相似文献39.
Background
Colorectal cancer (CRC) early detection improves health outcomes; screening programmes invest efforts in initiating invitations to target populations to be tested. Enhanced adherence is essential for reduction of morbidity and mortality. Participation rates in Israel are still relatively low.Objective
To explore lay views regarding the concept of receiving material incentives in exchange for enhanced adherence to CRC screening.Research design
Qualitative study. Between November 2009 and February 2010 six focus group discussions were carried out in two urban, middle and low socio‐economic status primary care clinics in a Northern city in Israel. Participants were eligible individuals for CRC screening, aged 50–68 (N = 24). Data analysis followed the principles of grounded theory, supported by qualitative software.Results
Participants found administering incentives in exchange for CRC screening inappropriate on rational and moral grounds. They valued their relations with the medical team and the health system more than the potential gain expected. Individuals eligible for CRC screening perceived themselves as responsible for their health, admitting difficulties in realizing this responsibility. Incentives were reported unsuitable for solving reported screening difficulties and a potential harm to the doctor–patient relationship.Conclusions
Focus group participants expressed an unconventional voice towards the use of material incentives. They pointed to the need for focused support of health behaviour change and valued their autonomy. While a proportion of the invitees in the target population see the importance of screening and appreciate the HMO''s initiative to invite them for testing, they also expressed their need for support from the HMO in realizing the recommended health behaviour. 相似文献40.
Michael M Havranek Matthias Vonmoos Christian P Müller Jessica R Büetiger Eve Tasiudi Lea M Hulka Katrin H Preller Rainald M?ssner Edna Grünblatt Erich Seifritz Boris B Quednow 《Neuropsychopharmacology》2015,40(13):2929-2937
Cocaine users consistently develop working memory (WM) impairments but the mediating molecular mechanisms are unknown so far. Recent evidence suggests that the serotonin (5-HT) system is altered by chronic cocaine use, while also being involved in WM processing. Thus, we investigated the effects of genetic variations impacting 5-HT activity and of peripheral 5-HT transporter (5-HTT) mRNA expression on WM performance in cocaine users and stimulant naive controls. Two hundred twenty participants (126 cocaine users, 94 controls) were assessed with visuospatial, spatial, and verbal WM tasks, genotyped for the length polymorphism in the promoter region of the 5-HTT (5-HTTLPR), the variable number of tandem repeats in the second intron of the 5-HTT (VNTR In2), two single-nucleotide polymorphisms (rs4570625 and rs1386497) in the tryptophan hydroxylase-2 (TPH2) gene and quantified for peripheral 5-HTT mRNA expression in whole-blood samples. Several significant gene × environment interactions between 5-HT genotypes and cocaine use on WM emerged: in cocaine users, the long/long (5-HTTLPR), 9+10/9+10 (VNTR In2) and C/C (TPH2 rs1386497) genotypes were risk alleles for WM impairments, whereas in healthy controls these polymorphisms were associated with improved WM performance. Analogously, high 5-HTT mRNA levels were associated with worse executive WM performance in cocaine users but with increased performance in controls. These gene × environment interactions suggest that the 5-HT system has an important role in the development of cognitive deficits in chronic cocaine users. Hence, pharmacological compounds targeting 5-HT neurotransmission might be promising for the treatment of cognitive deficits in cocaine dependence. 相似文献