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1.
The neonatal administration of 5,7-dihydroxytryptamine to rats (100 mg kg?1 s.c. on the 1st and 2nd day after birth) resulted in marked reductions in serotoninergic presynaptic markers ([3H]-5-HT synaptosomal uptake, tryptophan hydroxylase activity and endogenous 5-HT content) in various forebrain areas, particularly the cerebral cortex and the hippocampus. In contrast, this treatment produced an increased outgrowth of serotoninergic terminals in the brain stem as judged by the significant increments of these presynaptic markers in this region. Both in the hippocampus and the brain stem, these 5,7-dihydroxytryptamine-induced changes in serotoninergic innervation were associated with a transient increase in 5-HT-sensitive adenylate cyclase activity. No significant alteration of the specific high affinity binding of [3H]-5-HT to synaptosomal membranes from various brain regions was detected in 5,7-dihydroxytryptamine-treated rats for at least the first postnatal month.The chronic blockade of 5-HT receptors by metergoline (5 mg kg?1 day?1 from day 3 to day 22 after birth) altered neither the changes in presynaptic markers nor the evolution of [3H]-5-HT high affinity binding in 5,7-dihydroxytryptamine-treated rats.These findings further illustrate that the high affinity binding sites for [3H]-5-HT do not correspond to postsynaptic 5-HT receptors coupled to adenylate cyclase in the rat brain. Apparently, 5-HT receptors play no role in the increased outgrowth of serotoninergic systems in the brain stem following neonatal 5,7-dihydroxy-tryptamine treatment.  相似文献   

2.
The effect of B toxicity on antioxidant responses of soybean (Glycine max) cv. Athow was investigated by growing plants for 43 days at 0.2 (control), 2 and 12 mg B kg?1. At the end of the treatment period, shoot growth, lipid peroxidation level, the activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), and their isoenzymes in leaves were measured. Boron concentration in leaves was significantly increased by the increasing levels of B treatment from 43 to 522 mg kg?1, and shoot dry matter was depressed at 12 mg B kg?1. Significant increases in SOD, CAT, and APX activities were determined in leaves under 12 mg B kg?1; however, GR activities were decreased while POX activity was unchanged. Increased enzymic antioxidant activity arose from a combination of newly formed isoenzymes and activation of existing isoenzymes. By contrast, SOD and GR activities were decreased by 2 mg B kg?1 concentration as compared to the control groups while POX activity was increased and the activity of CAT did not change. Malondialdehyde content increased under 2 mg B kg?1 but decreased under 12 mg B kg?1. These results suggest that higher antioxidant activity observed under 12 than at 2 mg B kg?1 provided higher free radical-scavenging capacity, and thus a lower level of lipid peroxidation in Athow. While the induction of increased antioxidant activity was related to internal boron levels, the signaling and coordination of responses remain unclear.  相似文献   

3.
The effects of lisuride, d-lysergic acid diethyl amide (LSD) and apomorphine were studied in rats with unilateral destruction of nigro-striatal nerve terminals either with 6-hydroxydopamine (6-OHDA) or 5, 6-dihydroxytryptamine (5,6-DHT). Lisuride at the dose of 50 μg kg?1 i.p. induced contralateral turning for more than 4 hours while the circling induced by LSD (200 μg kg?1) and apomorphine (1 mg kg?1) persisted for only one hour. Lisuride, a compound stimulating both dopamine (DA) and 5-hydroxytryptamine (5-HT) receptors induced a more intense turning in 6-OHDA than in 5,6-DHT lesioned rats. This might indicate a modulation of 5-HT on rotational behavior. Haloperidol (1 mg kg?1 i.p.) antagonized both lisuride- and LSD-induced turning. LSD, and much more persistently lisuride, counteracted the prochlorperazine-induced catalepsy. These findings correlate with the biochemical data indicating that lisuride is a very potent agonist at central dopaminergic receptors.  相似文献   

4.
The presence of serotonin (5-HT) in dissected intestinal muscular wall of the caecum was demonstrated by the determination of endogenous level of the amine by both spectrofluorimetric and radioenzymatic assays. Biosynthesis of [3H]5-HT from [3H]tryptophan in in vitro conditions revealed the presence of tryptophan hydroxylase in these muscular layers and therefore strongly suggest the presence of serotoninergic neurons. Following dissection of the mucosa from the muscular layers containing the nerve plexuses, endogenous 5-HT and 5-hydroxyindol acetic acid levels as well as amounts of [3H]5-HT synthesized from [3H]tryptophan were always higher than those found in intact fragments of the caecum. These results are discussed in terms of metabolic processes involved in the regulation between the two 5-HT containing compartments.  相似文献   

5.
Experimental evidence on the protective properties of S-allylcysteine (SAC) was collected from three models exerting striatal toxicity. In the first model, SAC (120mg kg?1×5) prevented lipoperoxidation (LP) and mitochondrial dysfunction (MD) in synaptosomal fractions from 1-methyl-4-phenyl-1,2,3,6-tetrahydropiridinium-treated mice (30mg kg?1), but without complete restoration of dopamine levels. In the second model, SAC (300mg kg?1×3), prevented LP and MD in synaptosomes from rats infused with 6-hydroxydopamine (8µg µl?1) into the substantia nigra pars compacta, but again, without total reversion of depleted dopamine levels. In the third model, SAC (100 mg kg?1×1) prevented MD in synaptosomes from rats injected with 3-nitropropionic acid (10 mg kg?1), but in contrast to the other models, it failed to prevent LP. SAC also prevented the aberrant motor activity patterns evoked by the three toxins. Altogether, the results suggest that the antioxidant properties of SAC are responsible for partial or total preservation of neurochemical, biochemical and behavioural markers, indicating that pro-oxidant reactions underlie the neurotoxicity in these models.  相似文献   

6.
In mid-fifth-instar larvae of the southern armyworm, Spodoptera eridania, the subcellular distribution of four antioxidant enzymes—superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPOX), and glutathione reductase (GR)—were examined. Two-thirds (4.26 units ·mg protein?1) of the SOD activity was found in the cytosol, and one-thirds (2.13 units ·mg protein?1) in the mitochondria. CAT activity was unusually high and not restricted to the microsomal fraction where peroxisomes are usually isolated. The activity was distributed as follows: cytosol (163 units) mitochondria (125 units) and microsomes (119 units). Similar to CAT, the subcellular compartmentalization of both GPOX and GR was unusual. No activity was detected in the cytosol, but in mitochondria and microsomes, GR levels were 5.49 and 3.09 units. Although GPOX activity exhibited 14–16-fold enrichment in mitochondria and microsomes, respectively, over the 850g crude homogenate, the level was negligible (mitochondria = 1.4 × 10?3 units; microsomes = 1.6 × 10?3 units), indicating that this enzyme is absent. The unusual distribution of CAT has apparently evolved as an evolutionary answer to the absence of GR from the cytosol, and the lack of GPOX activity.  相似文献   

7.
Abstract

A sand hydroponic experiment with different concentrations of 0, 5, 10, 20, 40?mg L?1 Cd was used to study the growth and physiological response of Hylotelephium spectabile (Boreau) H. Ohba. and its phytoextraction potential for Cd. The results showed that total plant biomass under 5?mg L?1 Cd treatment was slightly affected. The content of malondialdehyde (MDA) in leaf exposed to Cd was higher, and the POD and CAT activity exhibited a positive response to the low level of Cd addition (5?mg·L?1). The photosynthesis pigments were slightly inhibited, and the ultrastructure of chloroplast remained intact after treatment with 10?mg L?1 Cd. The maximum leaf Cd content (603?mg·kg?1) was found in 5?mg L?1 Cd treatment, then decreased with the Cd level increased. The maximum Cd content in the shoots far exceeds the threshold level (100?mg kg?1) for a Cd-hyperaccumulator plant with the value of translocation factor (TFshoot/root) for Cd reaching up to 5.62. In conclusion, H. spectabile showed normal growth and physiological response and high shoot Cd accumulation under 5?mg L?1 Cd stress, which made it to be a good candidate for phytoextraction of low-level Cd polluted environment.  相似文献   

8.
The inhibition in the synthesis or bioavailability of nitric oxide (NO) has an important role in progress of hypertension. The blocking of nitric oxide synthase activity may cause vasoconstriction with the formation of reactive oxygen species (ROS). Propolis is a resinous substance collected by honey bees from various plants. Propolis has biological and pharmacological properties. The aim of this study was to examine the effect of propolis on catalase (CAT) activity, malondialdehyde (MDA) and NO levels in the testis tissues of hypertensive rats by Nω‐nitro‐l ‐arginine methyl ester (l ‐NAME). Rats have received nitric oxide synthase inhibitor (l ‐NAME, 40 mg kg?1, intraperitoneally) for 15 days to produce hypertension and propolis (200 mg kg?1, by gavage) during the last 5 days. MDA level in l ‐NAME‐treated group significantly increased compared with control group (P < 0.01). MDA level of l ‐NAME + propolis‐treated rats significantly reduced (P < 0.01) compared with l ‐NAME‐treated group. CAT activity and NO level significantly reduced (P < 0.01) in l ‐NAME group compared with control group. There were no statistically significant increases in the CAT activity and NO level of the l ‐NAME + propolis group compared with the l ‐NAME‐treated group (P > 0.01). These results suggest that propolis changes CAT activity, NO and MDA levels in testis of l ‐NAME‐treated animals, and so it may modulate the antioxidant system. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

9.
The present study was conducted to assess the influence of dietary zinc nanoparticles (size 50 nm) on the growth, biochemical constituents, enzymatic antioxidant levels and the nonspecific immune response of the freshwater prawn, Macrobrachium rosenbergii post larvae (PL). The concentrations of dietary supplement zinc nanoparticles (ZnNPs) were 0, 10, 20, 40, 60 and 80 mg kg?1 with the basal diet, and the level of Zn in ZnNP-supplemented diets were 0.71, 10.61, 20.73, 40.73, 60.61 and 80.60 mg kg?1, respectively. ZnNP-incorporated diets were fed to M. rosenbergii PL (initial body weight, 0.18?±?0.02 g) in a triplicate experimental setup for a period of 90 days. ZnNP supplemented feed fed PL up to 60 mg kg?1 showed significantly (P?<?0.05) improved performance in survival, growth and activities of digestive enzymes (protease, amylase and lipase). The concentrations of biochemical constituents (total protein, total amino acid, total carbohydrate and total lipid), total haemocyte count and differential haemocyte count were elevated in 10–60 mg kg?1 ZnNP supplemented feed fed PL. However, the PL fed with 80 mg ZnNPs kg?1 showed negative results. Activities of enzymatic antioxidants [superoxide dismutase (SOD) and catalase (CAT)], metabolic enzymes [glutamate–oxaloacetate transaminase (GOT) and glutamate–pyruvate transaminase (GPT)] and the process of lipid peroxidation (LPO) in the hepatopancreas and muscle showed no significant alterations in 10–60 mg kg?1 ZnNP supplemented feed fed PL. Whereas, 80 mg ZnNPs kg?1 supplemented feed fed PL showed significant elevations in SOD, CAT, LPO, GOT and GPT. Therefore, 80 mg ZnNPs kg?1 was found to be toxic to M. rosenbergii PL. Thus, the study suggests that up to 60 mg ZnNPs kg?1 can be supplemented for regulating survival, growth and immunity of M. rosenbergii.  相似文献   

10.
Intraperitonel (IP) injections of melatonin (4 mg kg?1) and chlorpromazine (25 mg kg?1), which blocks the breakdown of endogenous melatonin, significantly decreased temperatures selected by salamanders in a linear thermal gradient and eliminated the normal diel cycle in behavioral thermoregulation shown by control animals. Both endogenous and exogenous melatonin may play a crucial role in both physiological and behavioral thermoregulation of vertebrates.  相似文献   

11.
The role of same amendment on phytoremediating different level contaminated soils is seldom known. Soil pot culture experiment was used to compare the strengthening roles of cysteine (CY), EDTA, salicylic acid (Sa), and Tween 80 (TW) on hyperaccumulator Solanum nigrum L. phytoremediating higher level of single cadmium (Cd) or Benzo(a)pyrene (BAP) and their co-contaminated soils. Results showed that the Cd capacities (ug pot?1) in shoots of S. nigrum in the combined treatment T0.1EDTA+0.9CY were the highest for the 5 and 15 mg kg?1 Cd contaminated soils. When S. nigrum remediating co-contaminated soils with higher levels of Cd and BAP, that is, 5 mg kg?1 Cd + 1 mg kg?1 BAP and 15 mg kg?1 Cd + 2 mg kg?1 BAP, the treatment T0.9CY+0.9Sa+0.3TW showed the best enhancing remediation role. This results were different with co-contaminated soil with 0.771 mg kg?1 Cd + 0.024 mg kg?1 BAP. These results may tell us that the combine used of CY, SA, and TW were more useful for the contaminated soils with higher level of Cd and/or BAP. In the combined treatments of Sa+TW, CY was better than EDTA.  相似文献   

12.
Field survey, hydroponic culture, and pot experiments were carried out to examine and characterize cadmium (Cd) and zinc (Zn) uptake and accumulation by Sedum jinianum, a plant species native to China. Shoot Cd and Zn concentrations in S. jinianum growing on a lead/Zn mine area reached 103–478 and 4165–8349 mg kg?1 (DM), respectively. The shoot Cd concentration increased with the increasing Cd supply, peaking at 5083 mg kg?1 (DM) when grown in nutrient at a concentration of 100 μmol L?1 for 32 d, and decreased as the solution concentration increased from 200 to 400 μmol L?1. The shoot-to-root ratio of plant Cd concentrations was > 1 when grown in solution Cd concentrations ≤ 200 μmol L?1. Foliar, stem, and root Zn concentrations increased linearly with the increasing Zn level from 1 to 9600 μmol L?1. The Zn concentrations in various plant parts decreased in the order roots > stem > leaves, with maximum concentrations of 19.3, 33.8, and 46.1 g kg?1 (DM), respectively, when plants were grown at 9600 μmol Zn L?1 for 32 d. Shoot Cd concentrations reached 16.4 and 79.8 mg kg?1 (DM) when plants were grown in the pots of soil with Cd levels of 2.4 mg kg?1 and 9.2 mg kg?1, respectively. At soil Zn levels of 619 and 4082 mg kg?1, shoot Zn concentrations reached 1560 and 15,558 mg kg?1 (DM), respectively. The results indicate that S. jinianum is a Cd hyperaccumulator with a high capacity to accumulate Zn in the shoots.  相似文献   

13.
1. The levels of 5-HT, DA, NA and DA metabolites (NADA, DOPAC) measured by HPLC (with electrochemical detection) in the brain of the house cricket did not change over a 24-hr period. The level of 5-HIAA, a 5-HT metabolite, was below the limit of detection.2. The 5-HT and DOPAC levels decreased and NADA increased after quipazine injection but DA and NA levels did not change after it.3. [3H]Ketanserin was used to identify serotonin receptors bound to sites in the house cricket brain with a Kd of 5 nM and a concentration of Bmax 180 fmol/mg protein.  相似文献   

14.
The protective effects of an antioxidant combination in kidney injury induced by the injection of D‐galactosamine (D‐GaIN) were examined in the present study. Sprague Dawley female rats were used and divided into four groups as follows: (1) animals injected physiological saline solution, intraperitoneally, (2) animals treated with the combination of ascorbic acid (100 mg kg?1 day?1), β‐carotene (15 mg kg?1 day?1), α‐tocopherol (100 mg kg?1 day?1), and sodium selenate (0.2 mg kg?1 day?1) for three days orally, (3) rats injected D‐GaIN (500 mg kg?1) intraperitoneally as a single dose, and (4) animals treated with the antioxidant combination for three days, then injected D‐GaIN. The tissue and blood samples of animals were collected for morphological and biochemical evaluations. Histopathological injury in kidney tissues was observed together with a significant increase in tissue lipid peroxidation (LPO) level, myeloperoxidase (MPO), lactate dehydrogenase, catalase and superoxide dismutase (SOD) activities, and serum creatinine and urea levels, and a significant decrease in glutathione level and glutathione peroxidase activity in D‐GaIN injected rats. However, a decrease in the degenerative changes was detected in the kidney tissue of D‐GaIN + antioxidant group, and biochemical results showed reversed effects. In conclusion, it seems reasonable to conclude that the treatment of the antioxidant combination has a protective effect on D‐GaIN‐induced kidney injury of rats. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

15.
S. W. Evans  H. Bouwman 《Ostrich》2013,84(1-2):351-354
Evans, S.W. & Bouwman, H. 2000. The geographic variation and potential risk of DDT in the blood of Pied Kingfishers from northern KwaZulu-Natal, South Africa. Ostrich 71 (1 & 2): 351–354.

DDT has, since 1946 been used in the intradomicilliary control of malaria in northern KwaZulu-Natal. The Pied Kingfisher was selected as representative for organisms in relatively high trophic levels. Blood was obtained from Pied Kingfishers at Kosi Bay (n = 5), Pongolo Floodplain (n = 13), Mkuzi Nature Reserve (n = 4), Ndumu Nature Reserve (n = 4) and St Lucia (n = 3), extracted and analysed [SWEl] via gas chromatography. The highest blood DDE and σDDT concentrations were obtained for the birds from the Pongolo Floodplain (means of 95.92 μg 1?1/107.01 μg μg 1?1) and Kosi Bay Nature Reserve (means of 189.09 μg 1?l/241.8 μg 1?1). DDT was detected in the blood of Pied Kingfishers from Kosi Bay (mean 47.14 μg 1?1) and Pongolo Floodplain (mean 44.34 pg 1?1) only. This indicated their proximity to DDT application and the greater influx of DDT and its metabolites into the water component of these systems. The EDDT plasma concentrations in the Pied Kingfisher blood were calculated by multiplying the blood values of σDDT by 1.8. Using the regression, log10Y = 0.7785 + 0.8593 (log10X), relating the σDDT in eggs to σDDT in plasma of American Kestrel Falco sparverius it was possible to calculate the mean Pied Kingfisher egg σDDT concentration. The approximate mean Pied Kingfisher egg concentration of σDDT was calculated at 2.26 mg kg?1 for Kosi Bay and 1.24 mg kg?1 for the Pongolo Floodplain. Using the highest calculated plasma value of σDDT for Kosi Bay and the Pongolo Floodplain indicated that egg σDDT concentrations could be as high as 4.01 mg kg?1 and 4.17 mg kg?1 respectively. These calculated levels may be significant when compared to levels of DDE, known to have a detrimental effect, in the eggs of the Brown Pelican Pelecanus occidentalis, where a concentration of 2.5 to 3 mg kg?1 was associated with substantially impaired reproductive success. The highest calculated egg concentration was nearing this level and it is therefore possible that the Pied Kingfisher population may be at risk.  相似文献   

16.
The phytoremediation potential and responses of Sagittaria trifolia to diesel were investigated. In order to elucidate the biochemical and physiological responses of S. trifolia to diesel, the chlorophyll content, root vitality, soluble protein content and antioxidant enzymes activity (peroxidase (POD), catalase (CAT) and antioxidant enzymes superoxide dismutase (SOD)) were determined in the plant tissues after 50 d of diesel treatment. The results showed the presence of S. trifolia significantly improved the removal ratios of diesel, from 21~36% in the control soils to 54~85% in the planted soils. The chlorophyll content, root vitality and soluble protein content all increased at low diesel concentration, then decreased at high diesel concentration. The activities of CAT and POD exhibited peak values at 5 g·kg?1 diesel treatment and declined at higher diesel concentrations. However, the activity of SOD kept stable at lower diesel concentration (1 and 5 g·kg?1), and also declined at higher diesel concentration. Collectively, S. trifolia had the ability to tolerate certain amount of diesel, but when the concentration was up to 10 g·kg?1, the growth of S. trifolia would be restrained. The results also showed that variation of antioxidant enzyme activity was an important response in plants to diesel pollution.  相似文献   

17.
The ethanolic leaf extract (TZP) of Zuccagnia punctata, its ethereal fraction (Eet), 2′,4′‐dihydroxychalcone (DC), 2′,4′‐dihydroxy‐3′‐methoxychalcone (DMC) and 7‐hydroxy‐3′,4′‐dimethoxyflavone (HF) were evaluated as fungicide seed protectants on corn. Microdilution assays on a set of Fusarium strains showed minimum inhibitory concentrations (MICs) of 400–800 μg mL?1 (TZP), 50–100 μg mL?1 (Eet), 25–50 μg mL?1 (DC), 50–100 μg mL?1 (DMC) and 200–400 μg mL?1 (HF), with minimum fungicidal concentration (MFC)/MIC = 1. Suspensions of TZP, Eet, DC and DMC at MIC × 20 incorporated to the grains at rates of 1920, 240, 120 and 240 mg dry matter kg?1 of grain, respectively, increased the elongation of the primary roots (24–44%) and the number of seminal roots (44–50%). TZP also increased the number of secondary roots. HF was phytotoxic. Suspensions of TZP, Eet, DC and DMC suppressed the endogenous grain mycoflora at levels similar to those recorded for a thiram + carbendazim‐based fungicide. Grains treated with TZP (1920 mg kg?1), Eet (240 mg kg?1), DC (120 mg kg?1) and DMC (240 mg kg?1) stimulated the growth of the seedling root system both because of fungal suppression and hormetic effects in greenhouse curative and preventive assays against Fusarium verticillioides on a sand/soil substrate. Eet and its chalcones also reduced the severity of seedling blight more than the thiram + carbendazim‐based fungicide in preventive assays and led to the same disease severity observed for the fungicide treatment in the curative assays. Our results show that Eet and its chalcones not only were effective seed protectants against F. verticillioides and other seedborne fungi, but also improved the early performance of maize seedlings.  相似文献   

18.
Results from this study indicate that adult rat brain posesses guanylate cyclase activity sensitive to serotonin (5-HT) and localized in the synaptic plasma membrane. The enzyme appears to have multiple activation sites for 5-HT with specific activity maxima at the 5-HT concentrations of 5 × 10?10M and 7 × 10?8M respectively. The rates of guanosine-3′:5′-monophosphate (cyclic GMP) formation at these concentrations of 5-HT are, respectively, 170% and 307% above the endogenous or basal production rate of 2.7±0.3picomoles/minute/milligram of synaptosomal membrane protein. We have also been able to identify four distinct types (Type #1, #2, #3, and #4) of high affinity, specific binding sites for 5-HT on isolated synaptosomal membranes from rat brain. Dissociation constants of 2.6 × 10?10M, 2.5 × 10?9M, 7.0 × 10?9M, and 4.6 × 10?8M, characterize the binding of 5-HT to our sites of Type #1 through Type #4 respectively. The specific, high affinity binding was saturated at 5-HT concentrations of 5 × 10?10M for the Type #1 sites, 5 × 10?9M for our Type #2 sites, 1 × 10?8M for our Type #3 sites, and 7 × 10?8M for our Type #4 sites. The 5-HT concentrations producing saturation of our specific binding sites of Type #1 and Type #4 are virtually identical to those that elicit the two maxima of 5-HT stimulated cyclic GMP production, indicating that a membrane-bound guanylase cyclase may be closely associated with certain 5-HT receptors and/or re-uptake sites.  相似文献   

19.
Hesperidin (HES), a flavanone glycoside, predominant in citrus fruits, has an agonistic activity on peroxisome proliferator‐activated receptor gamma (PPAR‐γ). PPAR‐γ is an inhibitor of cardiac hypertrophy (CH) signaling pathways. In this study, we investigated the cardioprotective effect of HES in isoproterenol (ISO)‐induced CH through PPAR‐γ agonistic activity. For this, male albino Wistar rats were divided into six groups (n = 6), that is, normal, ISO‐control, HES treatment group (200 mg kg?1; p.o.), HES per se (200 mg kg?1; p.o.), enalapril treatment group (30 mg kg?1; p.o.), and combination group (HES 200 mg kg?1; p.o.+enalapril 30 mg kg?1; p.o.). ISO (3 mg kg?1; s.c.) was administered to all groups except normal and per se to induce CH. HES or enalapril treatment of 28 days significantly attenuated pathological changes, improved cardiac hemodynamics, suppressed oxidative stress, and apoptosis along with an increased PPAR‐γ expression. The combination of enalapril with HES exhibited an effect similar to that of HES or enalapril alone on all the aforementioned parameters. Therefore, HES may be further evaluated as a promising molecule for the alleviation of CH.  相似文献   

20.
Polycyclic aromatic hydrocarbons (PAHs) in the surface urban soils of Shenyang in Northeastern China were investigated. The total concentration of the PAHs ranged from 0.09 to 8.35 mg kg?1, with an average value of 1.51 ± 1.64 mg kg?1. 3–5-ring PAHs accounted for 90% of total PAHs. The functional areas, such as the industrial regions (4.95 mg kg?1) and main roads (1.56 mg kg?1), as well as the administrative divisions, including the districts of Shenhe (1.49 mg kg?1), Heping (2.08 mg kg?1), and Tiexi (2.14 mg kg?1), were heavily polluted by PAHs. The diagnostic ratios and principal component analysis (PCA) for PAHs indicate that the pollutants probably originated primarily from coal combustion and petroleum sources. The Nemerow composite index, used to assess environmental quality, shows that the soil samples were heavily polluted with PAHs, and although 52.8% of the soil sampling sites were safe, 47.2% of the soil sampling sites registered different grades of PAH pollution. The PAH contamination in Shenyang emphasizes the need for controlling fossil fuel combustion and traffic exhaust.  相似文献   

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