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Sequences highly similar (>95%) to the mouse mammary tumor virus (MMTV) env gene have been amplified from human DNA samples, including DNA samples from patients with breast cancer (BC) and persons who did not have BC. The sequences from human DNA were distinct from the MMTV sequences used as controls in these PCR reactions, indicating that these results are not simply due to contamination. In addition to both, mouse and human-related sequences were also amplified from some monkey and cat genomic DNA samples. These products were shown to be distinct from, but highly related to, the MMTV env gene, whereas, testing of other sources (lambda phage, snake, cockroach, sea urchin, chicken, or dog) demonstrated no specific amplification. A sequence 90% similar to the MMTV group antigen gene (gag) was amplified from cat DNA. These results indicate that DNA from vertebrate species other than rodents, including some but not all humans, monkeys, and cats, can contain sequences closely related to MMTV.  相似文献   
33.
The (α‐FeOOH) Goethite composite is a stable and an efficient catalyst in aqueous suspension under irradiation at 365 nm and by solar light. The photocatalytic activities of this composite were evaluated using Phenol Red (PR) dye (phenolsulfonphthalein class). In the dark, controlling factors, such as the pH and the adsorption of PR on Goethite surface were evaluated (before starting the photochemical experiments). It was found that the system PR‐Goethite present a small decrease in the main band of the dye (435 nm) which was explained by the low rate of adsorption of this dye on the Goethite. Also, we note that 40% of PR decolourisation was obtained after 200 min by the system PR‐Goethite‐hydrogen peroxide (H2O2) in dark due to the formation of ?OH by thermal decomposition of H2O2 on the surface of Goethite. The effects of various experimental parameters, such as initial dye concentration, pH, photocatalyst amount, tert‐Butyl alcohol effect and H2O2 addition were investigated in the study of photodegradation of the dye. The results showed that the photodegradation of PR under UV‐A (365 nm) irradiation could be enhanced greatly in the presence of H2O2. Natural radiation tests (under sunlight) showed that degradation was faster comparing with that obtained using the artificial one at 365 nm. Studies of the mineralization using total organic carbon method under naturel light certify that this method, compatible with the environment, may be considered in the treatment of wastewater and generally in the process of removal of this kind of pollutant.  相似文献   
34.
Municipal biosolids are a source of nutrients for crop production. Beneficial Management Practices (BMPs) can be used to minimize the risk of contamination of adjacent water resources with chemical or microbial agents that are of public or environmental health concern. In this field study, we applied biosolids slurry at a commercial rate using either subsurface injection or broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 22, 36 and 266 days post-application on 2 m2 microplots to evaluate surface runoff of 9 model pharmaceuticals and personal care products (PPCPs), atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole and triclosan. In runoff from the injected plots, concentrations of the model PPCPs were generally below the limits of quantitation. In contrast, in the broadcast application treatment, the concentrations of atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, sulfamethoxazole and triclosan on the day following application ranged from 70-1477 ng L− 1 in runoff and generally declined thereafter with first order kinetics. The total mass of PPCPs mobilized in surface runoff per m2 of the field ranged from 0.63 µg for atenolol to 21.1 µg for ibuprofen. For ibuprofen and acetaminophen, concentrations in runoff first decreased and then increased, suggesting that these drugs were initially chemically or physically sequestered in the biosolids slurry, and subsequently released in the soil. Carbamazepine and triclosan were detected at low concentrations in a runoff event 266 days after broadcast application. Overall, this study showed that injection of biosolids slurry below the soil surface could effectively eliminate surface runoff of PPCPs.  相似文献   
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Bulletin of Engineering Geology and the Environment - The spatial prediction of landslide susceptibility locations is a crucial task to support risk management and development plans in mountainous...  相似文献   
37.
The aim of the study was to determine if occupational exposure to hydrofluorocarbons (HFC) and hydrochlorofluorocarbons (HCFC) generates autoimmune responses against CYP2E1. HFCs and HCFCs have replaced the chlorofluorocarbons (CFC) in e.g. refrigeration installations and air-conditioning systems. During the substitution period, refrigeration mechanics reported symptoms like asthma, influenza-like reactions, and joint troubles. These symptoms resemble those of chronic inflammatory diseases with an autoimmune component. Since exposure to structurally similar chemicals, e.g. halothane, has previously been associated with autoimmune responses and diseases, autoimmunity among the refrigeration mechanics might hypothetically explain the reported inflammatory symptoms. Serum from 44 Swedish men, occupationally exposed to halogenated hydrocarbons, was screened for antibodies against CYP2E1 with enzyme-linked immunosorbent assay. Thirty of the workers had asthma, joint problems or influenza-like symptoms whereas 14 of them had no such symptoms. They were all selected from a cohort of 280 refrigeration mechanics. Unexposed, healthy, Swedish men (n=35) constituted control group. The study was approved by the Ethics Committee at Karolinska Institutet. No increase in autoantibodies against CYP2E1 was detected among the occupationally exposed workers as compared to the unexposed controls. Further, there was no difference in antibody titer between the exposed workers with symptoms and the exposed, asymtomatic workers or the unexposed controls. The present study does not completely exclude a connection between exposure and effect but makes the relation less likely at these exposure levels.  相似文献   
38.
Secondary exposure of vertebrate predators to second generation anticoagulant rodenticides (SGARs) is widespread in Britain. Tawny owl (Strix aluco) populations in the UK are thought to have declined since the 1970s, when SGARs were first introduced, and these compounds may have contributed to any decline in owl numbers. Our aims were to conduct the first systematic survey of SGAR exposure in tawny owls and ascertain whether there had been a change in the proportion of exposed birds that was concurrent with the decline in the population. Liver difenacoum, bromadiolone, flocoumafen and brodifacoum concentrations in British tawny owls from two periods (1990-1993 and 2003-2005) were quantified. In total, some 20% of birds contained detectable residues of one or more SGAR. The extent of exposure (% of birds exposed, magnitude of residues) to different SGARs did not change consistently between time periods. Of the raptors analysed to date in Britain, tawny owls had the lowest proportion of individuals that contained detectable liver residues and so appear to be the least vulnerable to exposure and/or assimilation of SGARs. We found no clear evidence to implicate SGARs as a major factor affecting tawny owl numbers in Britain between 1990 and 2005.  相似文献   
39.
Prior to 2000 a network of conventional ozone (O3) analysers existed in the Province of Firenze (Tuscany, central Italy). Between 2000 and 2004 the network was extended to incorporate a newly designed bioindicator network of tobacco plants (Nicotiana tabacum Bel W3). The objective was to set-up an integrated monitoring system to obtain estimates of ground-level O3 concentrations over the whole study area (3513 km2) in order to fill data gaps and cover reporting requirements. The existing conventional monitors were purposefully located mainly in urban areas. A total of 45 biomonitoring sites were selected using a systematic design to cover the target area. Two to five additional biomonitoring sites were co-located with conventional O3 analysers for calibration purposes, and five more sites for independent validation of modelled O3 concentrations. Visible Leaf Injury Index (LII) on the tobacco plants was significantly correlated (P: 0.018/0.0014) with a series of O3 exposure variables (mean of weekly 1-hour maxima, M1; mean of 7-hour means, M7; 24-hour mean, M24; and weekly AOT40). LII was found to be a significant predictor of weekly means of the O3 exposure variables with a standard error of estimates between 13.6 and 24.3 microg m(-3) (absolute values). LII was mapped with an ad-hoc spatial model over the study area at a 22 km grid resolution, and mapped values were used to predict O3 concentrations by means of a first order linear model. Results showed that high estimates of O3 (up to 188 microg m(-3) as mean of weekly maxima, M1) occurred more frequently in hilly and mountainous areas, with a spatial pattern changing on an annual basis. Predicted O3 concentrations were not significantly different from the measured concentrations (P: 0.34), although marked differences were observed for individual sites and years. The study provided evidence that integration of monitoring networks using different methods can be a viable option to obtain estimates of O3 concentrations over large areas.  相似文献   
40.
Anaerobic digestion is one of the most promising technologies for disposing olive mill wastewaters (OMWs). The process is generally carried out in the conventional contact bioreactors, which however are often unable to efficiently remove OMW phenolic compounds, that therefore occur in the effluents. The possibility of mitigating this problem by employing an anaerobic OMW-digesting microbial consortium passively immobilized in column reactors packed with granular activated carbon (GAC) or "Manville" silica beads (SB) was here investigated. Under batch conditions, both GAC- and SB-packed-bed biofilm reactors exhibited OMW COD and phenolic compound removal efficiencies markedly higher (from 60% to 250%) than those attained in a parallel anaerobic dispersed growth reactor developed with the same inoculum; GAC-reactor exhibited COD and phenolic compound depletion yields higher by 62% and 78%, respectively, than those achieved with the identically configured SB-biofilm reactor. Both biofilm reactors also mediated an extensive OMW remediation under continuous conditions, where GAC-reactor was much more effective than the corresponding SB-one, and showed a tolerance to high and variable organic loads along with a volumetric productivity in terms of COD and phenolic compound removal significantly higher than those averagely displayed by most of the conventional and packed-bed laboratory-scale reactors previously proposed for the OMW digestion.  相似文献   
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