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1.
Bufo gargarizans tadpoles were chronically exposed to waterborne fluoride at measured concentrations ranging from 0.4 to 61.2 mg F?/L for 70 days from Gosner stage 26 to completion of metamorphosis. The chronic exposure caused a concentration-dependent mortality in all tested fluoride concentrations. Total length, snout-to-vent length (SVL), body mass, and developmental stage of tadpoles were significantly inhibited at 42.6 mg F?/L. In addition, significant metamorphic delay and increase in size at completion of metamorphosis occurred after exposure to 19.8 mg F?/L. Moreover, 19.8 mg F?/L suppressed the bone mineralization of larvae at completion of metamorphosis. However, the bone mineralization could be enhanced by 4.1 mg F?/L. In conclusion, our results suggested that the presence of high concentrations of fluoride could increase mortality risk, delay metamorphosis, and suppress skeletal ossification in B. gargarizans larvae.  相似文献   

2.
The purpose of this study was to evaluate the steroidogenic effects of sertraline, a popular selective serotonin reuptake inhibitor, on larval fathead minnow (FHM; Pimephales promelas) and adult FHM. Larvae were exposed to 0.1, 1, and 10 µg/L sertraline for 28 days and analyzed for differential mRNA expression of 11β-hydroxysteroid dehydrogenase (11β-HSD), 20β-hydroxysteroid dehydrogenase (20β-HSD), aromatase (CYP19a), nuclear thyroid receptor alpha (TRα), and normalized to RP-L8. Adult FHM were exposed to 3 or 10 µg/L sertraline for 7 days and analyzed for differential expression of the same genes with the addition of thyroid receptor beta (TRβ). Larval FHM exposed to 0.1 μg/L had a significant upregulation of both 20β-HSD and TRα while adult FHM exposed to 10 µg/L had a significant upregulation of 11β-HSD expression in brain tissue. The significance of these findings with respect to survival, growth and reproduction are currently unknown, but represent areas for future research.  相似文献   

3.
We exposed marine clams (Ruditapes philippinarum) and aquatic worms (Hediste diversicolor) to environmentally relevant concentrations of two metal mixtures each containing three divalent metals [(C1 in µg/L) cadmium (Cd) 1, mercury (Hg) 0.1, and lead (Pb) 4] and [C2 in µg/L) Cd 17, Hg 1.1, and Pb 55]. Animals collected in the Arcachon Bay were exposed for 8 days in microcosms made up of a mixed biotope consisting of a water column and natural marine sediment both taken up from the Arcachon Bay. Bioaccumulation analysis showed a significant increase of Cd, Hg, and Pb in clams, particularly at C2 concentration in the water column reaching, in soft body, 2.3 ± 0.3 µg Cd/g, 0.7 ± 0.2 µg Hg/g, and 45 µg Pb/g dry weight (dw). DNA alterations and upregulation of the cox1 mitochondrial gene were also observed in clam gill after exposure to the metal blend. For worms exposed to the C2 metal blend, DNA alterations and significant increase of Cd and Hg concentrations were observed reaching 0.5 ± 0.1 µg Cd/g and 2 ± 0.6 µg Hg/g dw.  相似文献   

4.
We aimed to evaluate the criterion validity of the 2015 food-based Dutch dietary guidelines, which were formulated based on evidence on the relation between diet and major chronic diseases. We studied 9701 participants of the Rotterdam Study, a population-based prospective cohort in individuals aged 45 years and over [median 64.1 years (95%-range 49.0–82.8)]. Dietary intake was assessed at baseline with a food-frequency questionnaire. For all participants, we examined adherence (yes/no) to fourteen items of the guidelines: vegetables (≥200 g/day), fruit (≥200 g/day), whole-grains (≥90 g/day), legumes (≥135 g/week), nuts (≥15 g/day), dairy (≥350 g/day), fish (≥100 g/week), tea (≥450 mL/day), ratio whole-grains:total grains (≥50%), ratio unsaturated fats and oils:total fats (≥50%), red and processed meat (<300 g/week), sugar-containing beverages (≤150 mL/day), alcohol (≤10 g/day) and salt (≤6 g/day). Total adherence was calculated as sum-score of the adherence to the individual items (0–14). Information on disease incidence and all-cause mortality during a median follow-up period of 13.5 years (range 0–27.0) was obtained from data collected at our research center and from medical records. Using Cox proportional-hazards models adjusted for confounders, we observed every additional component adhered to was associated with a 3% lower mortality risk (HR 0.97, 95% CI 0.95; 0.98), lower risk of stroke (HR 0.95, 95% CI 0.92; 0.99), chronic obstructive pulmonary disease (HR 0.94, 95% CI 0.91; 0.98), colorectal cancer (HR 0.90, 95% CI 0.84; 0.96), and depression (HR 0.97, 95% CI 0.95; 0.999), but not with incidence of coronary heart disease, type 2 diabetes, heart failure, lung cancer, breast cancer, or dementia. These associations were not driven by any of the individual dietary components. To conclude, adherence to the Dutch dietary guidelines was associated with a lower mortality risk and a lower risk of developing some but not all of the chronic diseases on which the guidelines were based.  相似文献   

5.
Serum calcium measured in 27,158 subjects in 1994 and the calcium-sensing receptor polymorphism rs17251221 genotyped in 9,404 subjects were related to cardiovascular risk factors, incident myocardial infarction (MI), type 2 diabetes (T2DM), cancer and death during follow-up until 2008–2010. In a Cox regression model with adjustment for age, gender, smoking and body mass index, subjects with serum calcium 2.50–2.60 mmol/L had a significantly increased risk of incident MI [n = 1,802, hazards ratio (HR) 1.40, 95 % confidence interval (CI) 1.18, 1.66] and T2DM (n = 705, HR 1.49, 95 % CI 1.15, 1.94) and a significantly reduced risk of cancer (n = 2,222, HR 0.73, 95 % CI 0.62, 0.86) as compared to subjects with serum calcium 2.20–2.29 mmol/L. For rs17251221 there was a mean difference in serum calcium of 0.05 mmol/L between major and minor homozygote genotypes. No consistent, significant relation between rs17251221 and risk factors or the major hard endpoints were found. The minor homozygote genotype (high serum calcium) had a significant twofold increased risk (HR 2.32, 95 % CI 1.24, 4.36) for prostate cancer, as compared to the major homozygote. This may be clinically important if confirmed in other cohorts.  相似文献   

6.
Recent ecotoxicology studies have focused on the potential interaction of pesticides and the effects these interactions may have on aquatic ecosystems. We examined the combined effects of two insecticides, endosulfan and chlorpyrifos, that have been previously examined individually on survival, growth, and development of Pacific treefrog (Pseudacris regilla) tadpoles. Historically, both pesticides have been heavily used in the Central Valley of California, been identified in downwind montane areas, and are highly toxic to amphibian larvae. Tadpoles were exposed to chlorpyrifos and endosulfan individually and in combination from Gosner stage 25 through metamorphosis to evaluate the individual effects and the interaction between these insecticides. Chlorpyrifos alone did not affect survival or body size after 30 days, even at concentrations greater than the previously reported LC50. Survival and body size decreased with increasing endosulfan concentrations. The interactive effects of the insecticides depended on concentration and exposure duration. In combination, 137 µg/L chlorpyrifos inhibited the negative effects of endosulfan on growth and survival. The presence of both insecticides in combination facilitated the development of axial malformations. In the presence of endosulfan with either 266 or 394 µg/L chlorpyrifos, malformations occurred in 33 and 87 % of tadpoles, respectively. Our results indicate that organophosphorus and organochlorine pesticides with different modes of action can result in varying interactions depending on their concentrations and on the end points being assessed. Further examination of contaminant impacts on natural aquatic systems should continue to focus on the effects of multiple contaminants and their potential for unpredictable, nonadditive interactions.  相似文献   

7.
In an aging population, potentially modifiable factors impacting mortality such as diet quality, body mass index (BMI), and health-related quality of life (HRQOL) are of interest. Surviving members of the Geisinger Rural Aging Study (GRAS) (n = 5,993; aged ≥74 years) were contacted in the fall of 2009. Participants in the present study were the 2,995 (1,267 male, 1,728 female; mean age 81.4 ± 4.4 years) who completed dietary and demographic questionnaires and were enrolled in the Geisinger Health Plan over follow-up (mean = 3.1 years). Cox proportional hazards multivariate regression models were used to examine the associations between all-cause mortality and BMI, diet quality, and HRQOL. Compared to GRAS participants with BMIs in the normal range, a BMI < 18.5 was associated with increased mortality (HR 1.85 95% CI 1.09, 3.14, P = 0.02), while a BMI of 25–29.9 was associated with decreased risk of mortality (HR 0.71 95% CI 0.55, 0.91, P = 0.007). Poor diet quality increased risk for mortality (HR 1.53 95% CI 1.06, 2.22, P = 0.02). Finally, favorable health-related quality of life was inversely associated with mortality (HR 0.09 95% CI 0.06, 0.13, P < 0.0001). Higher diet quality and HALex scores, and overweight status, were associated with reduced all-cause mortality in a cohort of advanced age. While underweight (BMI < 18.5) increased risk of all-cause mortality, no association was found between obesity and all-cause mortality in this aged cohort.  相似文献   

8.
In this study, we assessed intracorporal mercury concentrations in subjects living on partially mercury-contaminated soils in a defined area in Switzerland. We assessed 64 mothers and 107 children who resided in a defined area for at least 3 months. Mercury in biological samples (urine and hair) was measured, a detailed questionnaire was administered for each individual, and individual mercury soil values were obtained. Human biomonitoring results were compared with health-related and reference values. Mothers and children in our study had geometric means (GMs) of 0.22 µg Hg/g creatinine in urine (95th percentile (P95) = 0.85 µg Hg/g) and 0.16 µg Hg/g (P95 = 0.56 µg Hg/g), respectively. In hair, mothers and children had GMs of 0.21 µg Hg/g (P95 = 0.94 µg/g) and 0.18 µg/g (P95 = 0.60 µg/g), respectively. We found no evidence for an association between mercury values in soil and those in human specimens nor for a health threat in residential mothers and children.  相似文献   

9.
With a growing number of prospective cohort studies, an updated dose–response meta-analysis of milk and dairy products with all-cause mortality, coronary heart disease (CHD) or cardiovascular disease (CVD) have been conducted. PubMed, Embase and Scopus were searched for articles published up to September 2016. Random-effect meta-analyses with summarised dose–response data were performed for total (high-fat/low-fat) dairy, milk, fermented dairy, cheese and yogurt. Non-linear associations were investigated using the spine models and heterogeneity by subgroup analyses. A total of 29 cohort studies were available for meta-analysis, with 938,465 participants and 93,158 mortality, 28,419 CHD and 25,416 CVD cases. No associations were found for total (high-fat/low-fat) dairy, and milk with the health outcomes of mortality, CHD or CVD. Inverse associations were found between total fermented dairy (included sour milk products, cheese or yogurt; per 20 g/day) with mortality (RR 0.98, 95% CI 0.97–0.99; I2 = 94.4%) and CVD risk (RR 0.98, 95% CI 0.97–0.99; I2 = 87.5%). Further analyses of individual fermented dairy of cheese and yogurt showed cheese to have a 2% lower risk of CVD (RR 0.98, 95% CI 0.95–1.00; I2 = 82.6%) per 10 g/day, but not yogurt. All of these marginally inverse associations of totally fermented dairy and cheese were attenuated in sensitivity analyses by removing one large Swedish study. This meta-analysis combining data from 29 prospective cohort studies demonstrated neutral associations between dairy products and cardiovascular and all-cause mortality. For future studies it is important to investigate in more detail how dairy products can be replaced by other foods.  相似文献   

10.
In the general population, the lowest mortality risk is considered to be for the body mass index (BMI) range of 20–24.9 kg/m2. In chronic diseases (chronic kidney disease, chronic heart failure or chronic obstructive pulmonary disease) the best survival is observed in overweight or obese patients. Recently above-mentioned phenomenon, called obesity paradox, has been described in patients with coronary artery disease. Our aim was to analyze the relationship between BMI and total mortality in patients after acute coronary syndrome (ACS) in the context of obesity paradox. We searched scientific databases for studies describing relation in body mass index with mortality in patients with ACS. The study selection process was performed according to PRISMA statement. Crude mortality rates, odds ratio or risk ratio for all-cause mortality were extracted from articles and included into meta-analysis. 26 studies and 218,532 patients with ACS were included into meta-analysis. The highest risk of mortality was found in Low BMI patients—RR 1.47 (95 % CI 1.24–1.74). Overweight, obese and severely obese patients had lower mortality compared with those with normal BMI–RR 0.70 (95 % CI 0.64–0.76), RR 0.60, (95 % CI 0.53–0.68) and RR 0.70 (95 % CI 0.58–0.86), respectively. The obesity paradox in patients with ACS has been confirmed. Although it seems to be clear and quite obvious, outcomes should be interpreted with caution. It is remarkable that obese patients had more often diabetes mellitus and/or hypertension, but they were younger and had less bleeding complications, which could have influence on their survival.  相似文献   

11.
To investigate risk factors for incident seizures among adult patients with depression. We conducted a nested case–control analysis in adult patients with newly diagnosed depression, using data from the U.K.-based Clinical Practice Research Datalink. Among cases with incident seizures and matched controls, we estimated odds ratios (ORs) with 95 % confidence intervals (CIs) of potential risk factors for seizures as reported from data of the general population: underweight (body mass index <18.5 kg/m2), smoking, alcoholism, drug abuse, psychiatric or neurologic comorbidities, and concomitant use of drugs. Of 186,540 patients with depression, 1489 developed a seizure during follow-up. Being underweight (OR 1.67 [95 % CI 1.23–2.26]), a current smoker (OR 1.45 [95 % CI 1.26–1.67]), having alcoholism (OR 2.98 [95 % CI 2.56–3.47]), and drug abuse (OR 2.51 [95 % CI 1.94–3.24]), were associated with increased risks of seizures compared to normal weight, non-smoking, no alcoholism, and no drug abuse, respectively. Previous stroke/transient ischemic attack (OR 6.07 [95 % CI 4.71–7.83]) or intracerebral bleeding (OR 8.19 [95 % CI 4.80–13.96]), and comorbid dementia (OR 6.83 [95 % CI 4.81–9.69]), were strongly associated with seizures. Current use of cephalosporins (OR 2.47 [95 % CI 1.61–3.78]) and antiarrhythmics (OR 1.59 [95 % CI 1.26–2.01]) was associated with an increased risk of seizures compared to non-use. Among adult patients with depression, being underweight, smoking, alcoholism, and drug abuse, were associated with seizures. Remote stroke and comorbid dementia were strong risk factors for seizures. Current use of cephalosporins or antiarrhytmics was associated with an increased risk of seizures compared to non-use.  相似文献   

12.
Recent studies have found that the risk of death continues to increase among female smokers, as compared with women who have never smoked. We wanted to examine the effect of smoking on all-cause and cause-specific mortality and calculate the corresponding population attributable fraction (PAF) of mortality in the Norwegian women and cancer study; a nationally representative prospective cohort study. We followed 85,320 women, aged 31–70 years, who completed a questionnaire in 1991–1997, through linkages to national registries through December 2008. Questionnaire data included information on lifestyle factors, including lifetime history of smoking. Poisson regression models were fitted to estimate relative risks (RRs) with 95 % confidence intervals (CIs) adjusting for age, birth cohort, education, postmenopausal status, alcohol consumption and body mass index, all at enrollment. During a mean follow-up time of 14 years 2,842 deaths occurred. Compared with that of never smokers, current smokers had a mortality rate that was double (RR = 2.34; 95 % CI 2.13–2.62) from deaths overall, triple (RR = 3.30; 95 % CI 2.21–4.82) from cerebrovascular disease and myocardial infarction (RR = 3.65; 95 % CI 2.18–6.15), 12 times (RR = 12.16; 95 % CI 7.80–19.00) from lung cancer and seventeen times (RR = 17.00; 95 % CI 5.90–48.78) from chronic obstructive pulmonary diseases. The PAF of mortality due to smoking was 34 % (CI 30–39). In summary, one in three deaths among middle aged women in Norway could have been prevented if the women did not smoke. More middle-aged women, than ever before, are dying prematurely due to smoking in Norway.  相似文献   

13.
In this study, we investigated the effects of depleted uranium (DU), the byproduct of nuclear enrichment of uranium, on several parameters related to defence system in the zebrafish, Danio rerio, using flow cytometry. Several immune cellular parameters were followed on kidney leucocytes: cell proportion, cell mortality, phagocytosis activity and associated oxidative burst and lysosomal membrane integrity (LMI). Effects of DU were tested ex vivo after 17 h of contact between DU and freshly isolated leucocytes from 0 to 500 µg DU/L. Moreover, adult zebrafish were exposed in vivo during 3 days at 20 and 250 µg DU/L. Oxidative burst results showed that DU increased reactive oxygen species (ROS) basal level and therefore reduced ROS stimulation index in both ex vivo and in vivo experiments. ROS PMA-stimulated level was also increased at 250 µg DU/L in vivo only. Furthermore, a decrease of LMI was detected after in vivo experiments. Cell mortality was also decreased at 20 µg DU/L in ex vivo experiment. However, phagocytosis activity was not modified in both ex vivo and in vivo experiments. A reduction of immune-related parameters was demonstrated in zebrafish exposed to DU. DU could therefore decrease the ability of fish to stimulate its own immune system which could, in turn, enhance the susceptibility of fish to infection. These results encourage the development and the use of innate immune analysis by flow cytometry in order to understand the effects of DU and more generally radionuclides on fish immune system and response to infectious diseases.  相似文献   

14.
High life in the sky? Mortality by floor of residence in Switzerland   总被引:1,自引:0,他引:1  
Living in high-rise buildings could influence the health of residents. Previous studies focused on structural features of high-rise buildings or characteristics of their neighbourhoods, ignoring differences within buildings in socio-economic position or health outcomes. We examined mortality by floor of residence in the Swiss National Cohort, a longitudinal study based on the linkage of December 2000 census with mortality and emigration records 2001–2008. Analyses were based on 1.5 million people living in buildings with four or more floors and 142,390 deaths recorded during 11.4 million person-years of follow-up. Cox models were adjusted for age, sex, civil status, nationality, language, religion, education, professional status, type of household and crowding. The rent per m2 increased with higher floors and the number of persons per room decreased. Mortality rates decreased with increasing floors: hazard ratios comparing the ground floor with the eighth floor and above were 1.22 [95 % confidence interval (CI) 1.15–1.28] for all causes, 1.40 (95 % CI 1.11–1.77) for respiratory diseases, 1.35 (95 % CI 1.22–1.49) for cardiovascular diseases and 1.22 (95 % CI 0.99–1.50) for lung cancer, but 0.41 (95 % CI 0.17–0.98) for suicide by jumping from a high place. There was no association with suicide by any means (hazard ratio 0.81; 95 % CI 0.57–1.15). We conclude that in Switzerland all-cause and cause-specific mortality varies across floors of residence among people living in high-rise buildings. Gradients in mortality suggest that floor of residence captures residual socioeconomic stratification and is likely to be mediated by behavioural (e.g. physical activity), and environmental exposures, and access to a method of suicide.  相似文献   

15.
Present investigation aimed to assess the alterations in branchial architecture of Ctenopharyngodon idellus exposed to chlorpyrifos. 96 h LC50 of chlorpyrifos to C. idellus was found to be 7.24 µg/L. Fish were exposed chronically to 2.41 and 1.44 µg/L sublethal concentrations (ecologically relevant concentrations) of chlorpyrifos for 15, 30 and 60 days. The gills of the CPF exposed fish showed partially affected secondary lamellae with shortening and curling, increased inter-lamellar space, sloughed off epithelium, hyperplasia and necrosis of pavement cells. On 60 days exposure, more pronounced degenerative changes, including severe necrosis, hyperplasia and hypertrophy of pavement cells, eroded and uplifted lamellar epithelium were noticed. Ultrastructural alterations include distorted nucleus and mitochondria in pavement cells, marked contraction in cisternae of golgi complex. Particularly in chloride cells, abundant mitochondria with distorted shape and size, dilation in between their cristae and tubular network were observed. The severity of damage was more profound at 60 days exposure. Thus, the observed cytopathological lesions of fish gills can be used as sensitive biomarkers for pesticide contamination.  相似文献   

16.

Purpose

Food-assistance program users are a specific group of nutritional concern, as they are often food insufficient and have poorer diet quality compared to non-food-assistance program users. The aim of our study was to assess dietary intake of Dutch food bank recipients (n = 167) and to compare this with dietary intake of a representative sample of the general population (Dutch National Food Consumption Survey (DNFCS-all): n = 1933), including a low-socioeconomic status (SES) sample (DNFCS-low SES: n = 312), using data from the DNFCS 2007–2010.

Methods

In this cross-sectional study, 12 food banks throughout The Netherlands participated. Food bank recipients’ characteristics were assessed with a self-administered questionnaire. Dietary intake data were collected through three 24-h recalls. Habitual dietary intake (mean, percentiles, and 95% CI) was estimated for all samples. Differences between samples were determined by comparing the 95% CIs.

Results

Mean age of the study population (62.9% female) was 48.6 years (SD:10.1). Mean energy intake was 1986 (95% CI 1830–2089) kcal. The majority of the Dutch food bank recipients had lower intakes than dietary reference intakes for dietary fiber, fruit, vegetables, and fish (range 86.6–99.3%), and a higher intake for saturated fat [88.1% (95% CI 84.1–98.9)]. Furthermore, mean intakes of energy, fiber, fruit, and vegetables were significantly lower in Dutch food bank recipients than in the DNFCS-all and the DNFCS-low-SES [e.g., daily mean fruit intake (g) food bank recipients 62.8 (95% CI 45.5–76.5), DNFCS-all 105.8 (95% CI 105.4–117.9), and DNFCS-low-SES 85.1 (95% CI 78.7–100.2)]. Fish intake was significantly lower compared with the DNFCS-all, but not compared with the DNFCS-low-SES.

Conclusions

Dutch food bank recipients, who largely rely on the content of food parcels, are not able to meet the nutritional guidelines for a healthy diet, and their dietary intake is poorer than the general as well as the low-SES sample of the Dutch adult population. More research is needed on how to improve the dietary intake of this vulnerable population subgroup, by, e.g., revising the content of the food parcels, and to develop effective intervention activities.
  相似文献   

17.
Studies have indicated hazardous consumption of large quantities of alcohol among adults in Lithuania. We assessed the associations of alcohol consumption at baseline with cancer incidence among men in a population-based cohort study, using Cox models adjusted for smoking, education and body mass index. Attained age was used as a time-scale. During follow-up (1978–2008) 1,698 men developed cancer. A higher amount of alcohol consumption (≥140.1 g/week vs. 0.1–10.0 g/week) was positively associated with increased risk of total cancer [hazard ratio (HR) = 1.36, 95 % confidence interval (95 % CI) 1.11, 1.65], upper aerodigestive tract cancer (HR = 2.79, 95 % CI 1.23, 6.34) and alcohol-related cancers (i.e. oral cavity, pharynx, larynx, oesophagus, colorectal and liver cancer) (HR = 1.88, 95 % CI 1.25, 2.85). Compared to occasional drinkers (a few times/year), drinkers 2–7 times/week showed an increased risk of total (HR = 1.45, 95 % CI 1.16, 1.83), alcohol-related (HR = 1.83 95 % CI 1.14, 2.93) and other cancers (HR = 1.35, 95 % CI 1.04, 1.76). Our results showed no statistically significant associations between quantity of alcohol intake per one occasion and risk of cancer. About 13 % of total, 35 % of upper aerodigestive tract, 22 % of alcohol-related and 10 % of other cancer cases were due to alcohol consumption in this cohort of men.  相似文献   

18.
In this study, muscle samples gathered from Largehead hairtail (Trichiurus lepturus Linneaus, 1758) and Savali hairtail [Lepturacanthus savala (Cuvier, 1829)] from the Karachi Fish Harbour, Pakistan were analyzed to determine heavy metal concentrations (iron [Fe], zinc [Zn], copper [Cu], manganese [Mn], lead [Pb] and cadmium [Cd]) between January and December 2016. All samples were analyzed using the AAnalyst 700 Flame Atomic Absorption Spectrophotometer. It was observed that the average measured level of Fe, Zn, Cu, Mn, Pb and Cd in muscle were 77.72?±?47.84 µg/g, 20.34?±?8.49 µg/g, 2.23?±?1.16 µg/g, 0.57?±?0.36 µg/g, 0.20?±?0.16 µg/g and 0.42?±?0.19 µg/g for T. lepturus, respectively. Besides, the average level of the same metal concentrations in muscle for L. savala were 85.11?±?57.64 µg/g, 16.63?±?9.25 µg/g, 2.53?±?1.90 µg/g, 0.47?±?0.27 µg/g, 0.23?±?0.18 µg/g and 0.47?±?0.20 µg/g, respectively. The correlation between size groups and metal accumulation in muscle tissues were investigated for both fish. In terms of public risk assessment, the provisional tolerable weekly intake’s of various heavy metals were compared with the consumption of both fish. As a result of the analysis, Fe, Zn, Cu, Mn, Pb and Cd accumulations in muscle tissues of T. lepturus and L. savala collected from Karachi Fish Harbour Pakistan did not exceed limit values.  相似文献   

19.
Endosulfan is an organochlorine pesticide that was recently labeled as a persistent organic pollutant, but it is still widely employed, particularly in developing countries. The goal of this study is to evaluate the acute (LC50) and chronic effects (developmental and behavioural traits) of this insecticide on Rana dalmatina tadpoles after exposure to ecologically relevant concentrations (0.005, 0.01, and 0.05 mg/L) by applying video-tracking techniques to evaluate the quantitative effect of endosulfan on amphibian behavioural patterns. The 96 h LC50 value was 0.074 mg endosulfan/L. Tadpoles chronically exposed to 0.01 and 0.05 mg endosulfan/L underwent high mortality rate, decreased larval growth, delayed development, and increased incidence of malformations, and they did not reach metamorphosis by the end of the experiment. Moreover, tadpoles exposed to these concentrations exhibited several abnormalities in swimming patterns, such as shorter distance moved, swirling, resting, and unusual use of space. The exposure to 0.005 mg endosulfan/L did not cause any significant effects on behaviour, larval growth, or development, but we observed a significant decrease in both survival and time to metamorphosis. We showed that developmental abnormalities are dose-dependent and that the pesticide effects could differ depending on the endosulfan concentration and the species tested. We also validated the hypothesis that behavioural analysis, along with the use of new analytical methods, could be a useful tool in amphibian ecotoxicological studies.  相似文献   

20.
Despite a potential preventive effect of physical activity on hepatobiliary cancer, little information is available on the relation between the two. We studied the association between frequency of vigorous physical activity and hepatobiliary cancer among 507,897 participants of the NIH-AARP Diet and Health Study, aged 50–71 years at baseline in 1995/1996. During 10 years of follow-up, 628 incident cases of liver cancer and 317 cases of extrahepatic biliary tract cancer were registered. Physical activity levels were assigned according to the frequency of engagement in 20 min or more of vigorous physical activity per week: never/rarely (lowest level), less than once per week, 1–2 times per week, 3–4 times per week, 5 or more times per week (highest level). Using Cox regression, multivariate-adjusted relative risks (RR) comparing the highest with the lowest level of physical activity revealed a statistically significant decreased risk for liver cancer (RR = 0.64, 95 % confidence interval (CI) = 0.49–0.84, p-trend <0.001), particularly hepatocellular carcinoma (RR = 0.56, 95 % CI = 0.41–0.78, p-trend <0.001), independent of body mass index. By comparison, multivariate analyses indicated that physical activity was not statistically significantly associated with extrahepatic bile duct cancer (RR = 0.86, 95 % CI = 0.45–1.65), ampulla of Vater cancer (RR = 0.66, 95 % CI = 0.29–1.48), or gallbladder cancer (RR = 0.63, 95 % CI = 0.33–1.21). These results suggest a potential preventive effect of physical activity on liver cancer but not extrahepatic biliary tract cancer, independent of body mass index.  相似文献   

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