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101.
Background
Ischemic heart disease (IHD) is one of the most important causes of mortality and morbidity in the Western world. There is a relationship between aging of the lens of the human eye and cardiovascular disease. The present study was conducted to examine if the risk of ischemic heart disease could be estimated by fluorophotometric assessment of lens aging. 相似文献102.
Pasi I. Jalava Maija-Riitta Hirvonen Markus Sillanpää Arto S. Pennanen Mikko S. Happo Risto Hillamo 《Inhalation toxicology》2013,25(12):994-1006
Epidemiological studies show heterogeneities in the particulate pollution-related exposure–effect relationships among cardiorespiratory patients, but the connection to chemical composition and toxic properties of the inhaled particles is largely unknown. To identify the chemical constituents and sources responsible for the diverse inflammatory and cytotoxic effects of urban air, fine (PM2.5–0.2) and coarse (PM10–2.5) particulate samples were collected during contrasting air pollution situations. We exposed mouse RAW 246.7 macrophages for 24?hrs to PM2.5–0.2 and PM10–2.5 samples from six European cities. The concentrations of proinflammatory cytokines (IL-6, TNFα), chemokine (MIP-2), and nitric oxide were measured from the cell culture medium, and the cytotoxicity was assayed. Spearman’s correlations between the chemical constituents and cellular responses were analyzed. In the PM2.5–0.2 size range, the tracers of photo-oxidation of organics in the atmosphere (oxalate, succinate, malonate), some transition metals (Ni, V, Fe, Cu, Cr), and insoluble soil constituents (Ca, Al, Fe, Si) correlated positively with the response parameters. In contrast, the tracers of incomplete biomass (monosaccharide anhydrides) and coal (As) combustion, and polycyclic aromatic hydrocarbons (PAHs), had negative correlations with the inflammatory activity. The compositions of PM10–2.5 samples were more uniform and there were only occasional high correlations between the chemical constituents, endotoxin, and the response parameters. The present results suggest that the local sources of incomplete combustion and resuspended road dust are important producers of harmful fine particulate constituents that may, however, operate via diverse toxicity mechanisms. The results agree well with our recent findings in the mouse lung. 相似文献
103.
The regional cochlear blood flow has been studied in the rabbit cochlea by mapping the distribution of non-radioactive microspheres in serial sections of plastic embedded cochleas. By using microspheres of two different colors injected at two different times, it is now possible to measure the 'regional' cochlear blood flow twice in the same animal. 相似文献
104.
Niels Hadrup Katrin Loeschner Karen Mandrup Gitte Ravn-Haren Henrik L. Frandsen Erik H. Larsen 《Drug and chemical toxicology》2019,42(1):76-83
Selenium (Se) nanoparticles have been proposed as food supplements. However, the particle formulation may exert unexpected toxicity. The aim was therefore to compare toxicity of low doses of Se nanoparticles and the dissolved, ionized Se species selenite. Female rats were dosed orally for 28?d with either: 0.05, 0.5, or 4?mg Se/kg body weight (bw)/day as 20?nm Se nanoparticles or 0.05 or 0.5?mg Se/kg bw/day as sodium selenite. Male rats were dosed 4?mg Se/kg bw/day as Se nanoparticles. Body weight and clinical appearance were recorded throughout the experiment. At necropsy, blood samples were taken for hematological and clinical chemistry analyses; organ weights were recorded. At the high-dose of Se nanoparticles, overt toxicity occurred and the female animals had to be euthanized prematurely, whereas the male animals were reduced in dose. At all doses of Se nanoparticles and at 0.5?mg Se/kg bw/day as selenite, a lower body weight gain as compared to vehicle occurred. Relative liver weight was increased for both Se formulations at 0.5?mg Se/kg bw/day. Creatinine clearance and urinary pH were affected in some Se dosed groups. There were no effects among dosed groups on brain neurotransmitters or on hematological parameters compared with controls. There were no histological changes in the livers of animals exposed to Se nanoparticles or to selenite. Based on effects on body weight and liver weight, selenium nanoparticles and ionic Se exerted similar toxicity. This suggests that a nanoparticle-specific toxicity of Se did not occur. 相似文献
105.
Pihl K Sørensen TL Nørgaard-Pedersen B Larsen SO Nguyen TH Krebs L Larsen T Christiansen M 《Prenatal diagnosis》2008,28(3):247-253
OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth weight, small for gestational age (SGA) and pre-term delivery. METHODS: A retrospective cohort study including 1,734 non-selected singleton pregnancies consecutively enrolled into the programme of first-trimester combined screening for DS in a 12-month period at a single centre. Data from the Prenatal Patient Registry in ASTRAIA were combined with the Danish National Newborn Screening Registry and Danish Birth Registry. RESULTS: There was a significant relation between low PAPP-A MoM, low beta-hCG MoM, increased risk estimate for DS and low birth weight and SGA. Low PAPP-A MoM and increased NT showed a significant relation to pre-term and spontaneous pre-term delivery. Low PAPP-A MoM showed a significant relation to early pre-term delivery. CONCLUSION: First-trimester screening markers exhibited a significant relation to low birth weight, SGA and to some extent, to pre-term and early pre-term delivery. The screening performance of individual markers was poor. 相似文献
106.
BACKGROUND: First-trimester maternal serum screening for Down syndrome (DS) can be improved by the use of additional serum markers. We examined whether progesterone (P), synthesized by placenta, might be a first-trimester maternal serum marker for fetal DS. MATERIALS AND METHODS: P was quantified in first-trimester maternal serum from 42 DS, six trisomy 18 and two trisomy 13 pregnancies and 115 controls. Log-regression of P versus gestational age in days was used to convert P concentrations into multiples of the median (MoM). RESULTS: The P concentrations in controls increased with gestational age (p = 9.5 x 10(-7)). The log10MoM P distribution in DS pregnancies was not significantly different from that in controls. However, from day 58-67, the log10MoM P was elevated in DS pregnancies (n = 10) with a mean (SD) of 0.1040 (0.0956), compared to a mean (SD) of - 0.0109 (0.1661) in controls (n = 24) (p = 0.05). Five out of six trisomy 18 and both trisomy 13 pregnancies had a P MoM < 1. CONCLUSION: P is not a useful marker for DS in first trimester, except perhaps in a narrow gestational age window from day 58 to 67. P is a trisomy 18/13 marker. 相似文献
107.
Intimate partner violence has been hypothesized as a factor associated with women's risk for problems in contraception use or access. This article explores differences in contraceptive use between abused and nonabused women, using a case-control study of 225 women. Women experiencing physical and emotional abuse were more likely to report not using their preferred method of contraception in the past 12 months compared with nonabused women (OR = 1.9; 95% CI = 1.0 to 3.7). Health care providers need to consider how intimate partner violence may influence their patients' use of contraceptives, which has implications for the high risk of unintended pregnancies among abused women. 相似文献
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