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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Joshua E Muscat Julie A Britton Mirjana V Djordjevic Marc L Citron Margaret Kemeny Erna Busch-Devereaux Brian Pittman Steven D Stellman 《Cancer epidemiology, biomarkers & prevention》2003,12(12):1474-1478
Several studies have measured the association between blood or adipose concentrations of organochlorinated compounds (OCs), such as pesticides and polychlorinated biphenyls (PCBs), and breast cancer. The estrogenic effects of OCs might adversely affect breast cancer recurrence. The participants were 224 women with nonmetastatic breast cancer enrolled in a New York-based case-control study. Supercritical fluid extraction followed by gas chromatography was conducted on adipose surgical specimens to determine OC concentrations. The mean follow-up time from surgery was 3.6 years. Thirty women (13.4%) were diagnosed with a recurrence. The concentration of pesticides and PCBs was correlated with baseline age and body mass index, but not with cancer stage. The highest tertile of total PCB concentration was associated with an increased risk of recurrence [relative risk (RR), 2.9; 95% confidence interval (CI), 1.02-8.2 versus the lowest tertile]. The risk for the highest tertile of the PCB congener Ballschmiter and Zell 118 was 4.0 (95% CI, 1.3-4.9). There was an increased risk for the middle level of the most abundant pesticide, 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (RR, 2.3; 95% CI, 0.9-5.7), and for beta-hexachlorocyclohexane, but not for their highest levels. Self-reported home termiticide exposure, alcohol consumption (> or = 1 drink/day), and race were not associated with prognosis. The RR for current cigarette smoking at diagnosis was 2.1 (95% CI, 0.9-5.1). In contrast to previous data showing no relationship between OC exposure and risk of breast cancer in these women, adipose PCB concentrations were associated with tumor recurrence. Pesticide levels were not related to recurrence. 相似文献
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Wanitchaya Kittikraisak Taweewun Hunsawong Somsak Punjasamanvong Thanapat Wongrapee Patama Suttha Phunlerd Piyaraj Chaniya Leepiyasakulchai Chuleeekorn Tanathitikorn Pornsak Yoocharoen Anthony R. Jones Duangrat Mongkolsirichaikul Matthew Westercamp Eduardo AzzizBaumgartner Joshua A. Mott Suthat Chottanapund 《Influenza and other respiratory viruses》2022,16(4):662
BackgroundWe examined SARS‐CoV‐2 anti‐spike 1 IgG antibody levels following COVID‐19 vaccination (AstraZeneca [AZ], Sinovac [SV], Pfizer‐BioNTech [PZ]) among Thai healthcare providers.MethodsBlood specimens were tested using enzyme‐linked immunosorbent assay. We analyzed seven vaccination regimens: (1) one dose of AZ or SV, (2) two doses of homologous (2AZ, 2SV) or heterologous (1AZ + 1PZ) vaccines, and (3) three doses of heterologous vaccines (2SV + 1AZ, 2SV + 1PZ). Differences in antibody levels were assessed using Kruskal–Wallis statistic, Mann–Whitney test, or Wilcoxon matched‐pairs signed‐rank test. Antibody kinetics were predicted using fractional polynomial regression.ResultsThe 563 participants had median age of 39 years; 92% were female; 74% reported no underlying medical condition. Antibody levels peaked at 22–23 days in both 1AZ and 2SV vaccinees and dropped below assay''s cutoff for positive (35.2 binding antibody units/ml [BAU/ml]) in 55 days among 1AZ vaccinees compared with 117 days among 2SV vaccinees. 1AZ + 1PZ vaccination regimen was highly immunogenic (median 2279 BAU/ml) 1–4 weeks post vaccination. 2SV + 1PZ vaccinees had significantly higher antibody levels than 2SV + 1AZ vaccinees 4 weeks post vaccination (3423 vs. 2105 BAU/ml; p‐value < 0.01), and during weeks 5–8 (3656 vs. 1072 BAU/ml; p‐value < 0.01). Antibodies peaked at 12–15 days in both 2SV + 1PZ and 2SV + 1AZ vaccinees, but those of 2SV + 1AZ declined more rapidly and dropped below assay''s cutoff in 228 days while those of 2SV + 1PZ remained detectable.Conclusions1AZ + 1PZ, 2SV + 1AZ, and 2SV + 1PZ vaccinees had substantial IgG levels, suggesting that these individuals likely mounted sufficient anti‐S1 IgG antibodies for possible protection against SARS‐CoV‐2 infection. 相似文献
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Paul M Garrett Joshua P White Simon Dennis Stephan Lewandowsky Cheng-Ta Yang Yasmina Okan Andrew Perfors Daniel R Little Anastasia Kozyreva Philipp Lorenz-Spreen Takashi Kusumi Yoshihisa Kashima 《JMIR Public Health and Surveillance》2022,8(7)
BackgroundIn response to the COVID-19 pandemic, countries are introducing digital passports that allow citizens to return to normal activities if they were previously infected with (immunity passport) or vaccinated against (vaccination passport) SARS-CoV-2. To be effective, policy decision-makers must know whether these passports will be widely accepted by the public and under what conditions. This study focuses attention on immunity passports, as these may prove useful in countries both with and without an existing COVID-19 vaccination program; however, our general findings also extend to vaccination passports.ObjectiveWe aimed to assess attitudes toward the introduction of immunity passports in six countries, and determine what social, personal, and contextual factors predicted their support.MethodsWe collected 13,678 participants through online representative sampling across six countries—Australia, Japan, Taiwan, Germany, Spain, and the United Kingdom—during April to May of the 2020 COVID-19 pandemic, and assessed attitudes and support for the introduction of immunity passports.ResultsImmunity passport support was moderate to low, being the highest in Germany (775/1507 participants, 51.43%) and the United Kingdom (759/1484, 51.15%); followed by Taiwan (2841/5989, 47.44%), Australia (963/2086, 46.16%), and Spain (693/1491, 46.48%); and was the lowest in Japan (241/1081, 22.94%). Bayesian generalized linear mixed effects modeling was used to assess predictive factors for immunity passport support across countries. International results showed neoliberal worldviews (odds ratio [OR] 1.17, 95% CI 1.13-1.22), personal concern (OR 1.07, 95% CI 1.00-1.16), perceived virus severity (OR 1.07, 95% CI 1.01-1.14), the fairness of immunity passports (OR 2.51, 95% CI 2.36-2.66), liking immunity passports (OR 2.77, 95% CI 2.61-2.94), and a willingness to become infected to gain an immunity passport (OR 1.6, 95% CI 1.51-1.68) were all predictive factors of immunity passport support. By contrast, gender (woman; OR 0.9, 95% CI 0.82-0.98), immunity passport concern (OR 0.61, 95% CI 0.57-0.65), and risk of harm to society (OR 0.71, 95% CI 0.67-0.76) predicted a decrease in support for immunity passports. Minor differences in predictive factors were found between countries and results were modeled separately to provide national accounts of these data.ConclusionsOur research suggests that support for immunity passports is predicted by the personal benefits and societal risks they confer. These findings generalized across six countries and may also prove informative for the introduction of vaccination passports, helping policymakers to introduce effective COVID-19 passport policies in these six countries and around the world. 相似文献
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Buhimschi CS Turan OM Funai EF Azpurua H Bahtiyar MO Turan S Zhao G Dulay A Bhandari V Copel JA Buhimschi IA 《Obstetrics and gynecology》2008,111(3):715-722
OBJECTIVE: Fetal adaptation to stress is regulated in part by the pituitary-adrenocortical system. The stress hormones dehydroepiandrosterone sulfate (DHEAS) and cortisol have opposing effects: cortisol suppresses while DHEAS enhances immune functions. We sought to estimate the impact of intraamniotic inflammation on fetal adrenal gland volume and cortisol-to-dehydroepiandrosterone sulfate ratio (fetal stress ratio) in pregnancies complicated by preterm birth. METHODS: Fifty-one consecutive singleton fetuses of mothers who had an indicated amniocentesis to rule out infection were analyzed. Intraamniotic inflammation was assessed by proteomic profiling of amniotic fluid for the biomarkers of the Mass Restricted score. The Mass Restricted score ranges from 0 (biomarkers absent) to 4 (all biomarkers present), with Mass Restricted scores of 3 or 4 indicating severe intraamniotic inflammation. Fetal adrenal gland volume was assessed by three-dimensional ultrasonography and corrected for estimated fetal weight. Interleukin-6 (IL-6), cortisol, and DHEAS were measured by immunoassay. RESULTS: Women with intraamniotic inflammation delivered earlier (27.8+/-3.4 weeks, n=16, compared with 32.3+/-3.0 weeks, n=35, P<.001), and their fetuses had higher cord blood IL-6 (P=.011) and higher corrected adrenal gland volumes (P=.027). Cord blood IL-6 levels were in direct relationship with corrected adrenal volume (r=0.372, P=.019), fetal cortisol (r=0.428, P=.010), and DHEAS (r=0.521, P<.001). However, fetuses exposed to intraamniotic inflammation had an overall lower fetal stress ratio (P=.034). These results maintained after adjusting for gestational age, uterine contractions, and steroid exposure. CONCLUSION: Fetuses exposed to intraamniotic inflammation have higher adrenal gland volumes and lower cortisol-to-DHEAS ratios, suggesting that the fetal adrenocortical axis plays a role in the intrauterine adaptation to inflammation. 相似文献
49.
Press JZ Kenyon JA Xue H Miller MA De Luca A Miller DM Huntsman DG Gilks CB McAlpine JN Wang YZ 《Gynecologic oncology》2008,110(2):256-264
50.
Gutiérrez M Suyama TL Engene N Wingerd JS Matainaho T Gerwick WH 《Journal of natural products》2008,71(6):1099-1103
Cancer cell toxicity-guided fractionation of extracts of the Papua New Guinea marine cyanobacteria Lyngbya majuscula and Lyngbya sordida led to the isolation of apratoxin D (1). Compound 1 contains the same macrocycle as apratoxins A and C but possesses the novel 3,7-dihydroxy-2,5,8,10,10-pentamethylundecanoic acid as the polyketide moiety. The planar structures and stereostructures of compound 1 were determined by extensive 1D and 2D NMR and MS data analyses and by comparison with the spectroscopic data of apratoxins A and C. Apratoxin D (1) showed potent in vitro cytotoxicity against H-460 human lung cancer cells with an IC 50 value of 2.6 nM. 相似文献