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71.
OSHAUG ARNE; BJONNES CHRISTINE HELLE; BUGGE KARI H.; TRYGG KERSTIN U. 《European journal of public health》1996,6(3):196-202
The objective of the study was to examine whether male tobaccosmokers had a more unhealthy diet than non-smokers. Data onsmoking and other variables were collected by questionnaireinterviews and food intake by one 24 h recall. The setting was2 oll platforms. The participants were 310 healthy men workingon 2 platforms in the Norwegian sector of the North Sea. Themean ages were 37 and 39 years for non-smokers and smokers.The prevalence of smoking was 50.3%. Smoking decreased withincreasing level of education, but increased with degree ofurbanization. Smokers consumed less vegetables, fruit and fish,but more meat, soft drinks containing sugar and more coffeethan non-smokers. Smokers had a higher intake of fat and a lowerintake of carbohydrate, vitamins A, D and C and dietary fibre.Smoking was an independent predictor for increasing the consumptionof coffee and high intake of energy, energy from fat and cholesteroland a decreasing consumption of vegetables, fruit, energy fromcarbohydrates, dietary fibre and vitamins A and C. It is concludedthat smokers had a more unhealthy diet than non-smokers. 相似文献
72.
Marcelino Avils-Trigueros Juan A. Quesada 《Anatomical record (Hoboken, N.J. : 2007)》1995,242(1):83-90
Background: In vertebrates the thymus is primarily regarded as a lymphoid organ whose importance lies in its capacity to produce a large number of lymphocytes that enter the circulation as T cells. In higher vertebrates the organ has also been regarded as a site for my elopoiesis, but this capacity has not been observed in fish. In this study we describe morphologically the presence of intrathymic developing myeloid cells in the sea bass. Methods: The thymus samples were morphologically studied by transmission electron microscopy. Results: We describe the coexistence of cells in different stages of erythropoiesis and granulopoiesis that appear to be developing in situ in some thymus lobes. Degenerated thymocytes and epithelial-reticular cells occur simultaneously in the same areas. Conclusions: The coexistence of different cellular components of erythropoiesis and the heterophilic series of granulopoiesis with areas of necrosis suggests a relationship between both processes that is influenced by the microenvironment. Our observations also suggest that the presence of intrathymic developing myeloid cells may imply a nonimmunological role for the thymus. © 1995 Wiley-Liss, Inc. 相似文献
73.
Ndungu K 《Environmental research》2011,(1):45-49
The increased use of silver as a biocide in nanoparticle formulations has heightened concern on possible environmental implications owing to its toxicity. There is however very little data on the concentration levels of silver in marine and freshwaters. Here, I report data on dissolved (<0.4 μm filter) silver concentration in the surface waters of the Baltic Sea, the first such data reported for a European coastal water body. Levels of dissolved silver in the Baltic are comparable to those reported for other American estuarine waters and range from non-detectable in the open Baltic Sea Proper (<1 pM) to 9.4 pM (1 ng/L) in the Stockholm Archipelago, with a mean of 2.8 pM (0.2 ng/L). Inputs from wastewater treatment are clearly discernable and might constitute the main source of silver to the Stockholm Archipelago and possibly the Baltic Sea Proper. 相似文献
74.
The aims of this work were: (1) identification of the metallothionein (MT) gene coding sequence in order to prepare an MT probe in Scapharca inaequivalvis and (2) quantification of Cd, Zn, Cu, MT and MTmRNA expression in tissues of molluscs from three areas along the Northern Adriatic coast of Italy. By RT-PCR we cloned the MTcDNA of S. inaequivalvis using the RNA extracted from hepatopancreas of specimens exposed to Cd. The 61 amino acids sequence of MT was deduced and was 70% identical to S. brughtonii MT. Cd concentration in molluscs from the wild was significantly higher in gills from specimens sampled near Ravenna. Zn concentration in the same tissue was significantly higher in Ravenna with respect to Porto Garibaldi while no difference with respect to Cesenatico was detected. Cu levels showed significant differences among sites in gills and mantle whereas values in the hepatopancreas were similar in all sites. The low MT levels were indicative of a low metal exposure; few differences were found in MTmRNA concentrations, which resulted significantly higher in hepatopancreas of molluscs from Porto Garibaldi. 相似文献
75.
Buznikov GA Nikitina LA Rakić LM Milosević I Bezuglov VV Lauder JM Slotkin TA 《Brain research bulletin》2007,74(4):221-231
Lower organisms show promise for the screening of neurotoxicants that might target mammalian brain development. Sea urchins use neurotransmitters as embryonic growth regulatory signals, so that adverse effects on neural substrates for mammalian brain development can be studied in this simple organism. We compared the effects of the organophosphate insecticide, chlorpyrifos in sea urchin embryos with those of the monoamine depleter, reserpine, so as to investigate multiple neurotransmitter mechanisms involved in developmental toxicity and to evaluate different therapeutic interventions corresponding to each neurotransmitter system. Whereas reserpine interfered with all stages of embryonic development, the effects of chlorpyrifos did not emerge until the mid-blastula stage. After that point, the effects of the two agents were similar. Treatment with membrane permeable analogs of the monoamine neurotransmitters, serotonin and dopamine, prevented the adverse effects of either chlorpyrifos or reserpine, despite the fact that chlorpyrifos works simultaneously through actions on acetylcholine, monoamines and other neurotransmitter pathways. This suggests that different neurotransmitters, converging on the same downstream signaling events, could work together or in parallel to offset the developmental disruption caused by exposure to disparate agents. We tested this hypothesis by evaluating membrane permeable analogs of acetylcholine and cannabinoids, both of which proved effective against chlorpyrifos- or reserpine-induced teratogenesis. Invertebrate test systems can provide both a screening procedure for mammalian neuroteratogenesis and may uncover novel mechanisms underlying developmental vulnerability as well as possible therapeutic approaches to prevent teratogenesis. 相似文献
76.
Man-made endocrine-disrupting chemicals (EDCs) range across all continents and oceans. Some geographic areas are potentially more threatened than others: one of these is the Mediterranean Sea. Levels of some xenobiotics are much higher here than in other seas and oceans. In this paper we review the final results of a project supported by the Italian Ministry of the Environment, in which the hypothesis that Mediterranean top predator species (such as large pelagic fish and marine mammals) are potentially at risk due to EDCs was investigated. We illustrate the need to develop and apply sensitive methodological tools, such as biomarkers (Vitellogenin, Zona Radiata proteins and CYP1A activities) for evaluation of toxicological risk in large pelagic fish top predators (Swordfish, (Xiphias gladius), Bluefin Tuna (Thunnus thynnus thynnus)) and nondestructive biomarkers (CYP1A activities and fibroblast cell culture in skin biopsy), for the hazard assessment of threatened marine mammals species (Striped Dolphin, (Stenella coeruleoalba), Bottlenose Dolphin (Tursiops truncatus), Common Dolphin (Delphinus delphis) and Fin Whale (Balaenoptera physalus))exposed to EDCs. Differential gender susceptibility to EDCs is also explored both in large pelagic fish and in cetaceans. In cetaceans, male specimens showed higher cytochrome P450 induction (BPMO in skyn biopsies, CYP2B in fibroblasts cell cultures) by xenobiotics with respect to females. 相似文献
77.
Sipiä V Kankaanpää H Peltonen H Vinni M Meriluoto J 《Ecotoxicology and environmental safety》2007,66(3):421-425
Nodularin (NODLN) is a hepatotoxin produced by the cyanobacterium Nodularia spumigena, which occurs regularly in the Baltic Sea. The primary aim of this study was to study the transfer of NODLN to three-spined stickleback (Gasterosteus aculeatus L.), herring (Clupea harengus membras L.), and salmon (Salmo salar L.), which were caught from the northern Baltic Sea between August 2002 and August 2003. Liquid chromatography mass spectrometry (LC-MS) was used for NODLN analysis. NODLN was found in both herring (0–90 μg kg−1 dw) and three-spined sticklebacks samples (2.8–700 μg kg−1 dw). The recovery for the spiked stickleback samples in vitro was 28%. Only 1 salmon of a total of 10 contained a small amount of NODLN (10 μg kg−1 dw). However, the high concentrations in individual stickleback suggest that possible transfer to higher trophic levels deserves more research. 相似文献
78.
The objective of this study was to contribute to our understanding of the role of sex steroids in fish sex differentiation and male maturation. Sexually undifferentiated sea bass were administered 17α-methyldihydrotestosterone (MDHT), estradiol-17β (E2), fadrozole (Fz), cyproterone acetate (CPA) or tamoxifen (Tx). MDHT produced 100% males whereas E2 and Tx resulted in 100% females. Fz produced 95% males while CPA did not alter sex ratios. E2 treatment did not affect gonadal aromatase (cyp19a) expression levels, supporting the possibility that the feminizing effect of exogenous E2 are not directly related to cyp19a regulation. Both MDHT and Fz decreased cyp19a expression. Moreover, androgen receptor (ar) expression levels increased during development in all but the MDHT group, suggesting that early exposure to an androgen down-regulates subsequent ar expression in males and that Fz does not interact with the androgen receptor. Together, these observations indicate that although MDHT and Fz result in a similar phenotype, the molecular pathways involved are likely different, and show that Fz masculinization is the consequence of inhibited ovarian differentiation rather than of a direct androgenic effect. Further, since CPA did not alter sex ratios when administered during the period of highest androgen sensitivity, we suggest that androgens are not required for initial testicular differentiation in the sea bass. MDHT and Fz did not alter the number of precocious males but reduced and increased, respectively, their gonadosomatic index (GSI). In addition, Fz had lasting effects on the GSI of precocious and non-precocious males, probably due to alterations of estrogen function in the testis. 相似文献
79.
Uskul AK Kitayama S Nisbett RE 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(25):8552-8556
It has been proposed that social interdependence fosters holistic cognition, that is, a tendency to attend to the broad perceptual and cognitive field, rather than to a focal object and its properties, and a tendency to reason in terms of relationships and similarities, rather than rules and categories. This hypothesis has been supported mostly by demonstrations showing that East Asians, who are relatively interdependent, reason and perceive in a more holistic fashion than do Westerners. We examined holistic cognitive tendencies in attention, categorization, and reasoning in three types of communities that belong to the same national, geographic, ethnic, and linguistic regions and yet vary in their degree of social interdependence: farming, fishing, and herding communities in Turkey's eastern Black Sea region. As predicted, members of farming and fishing communities, which emphasize harmonious social interdependence, exhibited greater holistic tendencies than members of herding communities, which emphasize individual decision making and foster social independence. Our findings have implications for how ecocultural factors may have lasting consequences on important aspects of cognition. 相似文献
80.
Nakata H Shimada H Yoshimoto M Narumi R Akimoto K Yamashita T Matsunaga T Nishimura K Tanaka M Hiraki K Shimasaki H Takikawa K 《Bulletin of environmental contamination and toxicology》2008,80(1):78-84
The concentrations and distribution of heavy metals, such as mercury, zinc, copper, lead, and iron in surface sediments from
234 stations of the Yatsushiro Sea including Minamata bay were investigated. High concentrations of mercury were found in
sediments from Minamata bay and its vicinity, but the levels decreased gradually with distance from the bay. The concentrations
of mercury in sediments decreased gradually from south to north of the Yatsushiro Sea. These imply the lack of movement of
mercury from Minamata bay to the northern Yatsushiro Sea. The geographical profiles of zinc and copper were contrary to that
found for mercury, indicating the presence of natural and anthropogenic sources of copper and zinc in the northern Yatsushiro
Sea. 相似文献