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131.
Fisheries Science - Intensive commercial harvesting of the wedge clam Donax trunculus and the striped venus Chamelea gallina was conducted along the southern coast of the Marmara Sea using a... 相似文献
132.
Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target
organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0 mg/L Zn, 1.0 mg/L Cd, and 5.0 mg/L Zn + 1.0 mg/L Cd mixture for 7 and 28 days, and alterations in serum
enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time
dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities
of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7 days while they
increased at 28 days. Fish exposed to metals showed a decrease in cholinesterase activity at 7 days followed by a return to
control levels at the end of the exposure period. The individual and combined effects of metals caused a decline in levels
of Na+, Cl−, and Ca2+, especially at 28 days. K+ level increased at 7 days but it returned to control levels with increasing duration of exposure. This study indicated that
the alterations in serum parameters may be a result of the target tissue (i.e., liver, gill, and kidney) damage and dysfunction
induced by the metals and that these parameters can thus be used to assess the effects of metals on organisms. 相似文献
133.
134.
Ali Tuğrul Akin Emel Öztürk Emin Kaymak Derya Karabulut Birkan Yakan 《Anatomia, histologia, embryologia》2021,50(6):908-917
Cancer is a lethal disease that is characterized by uncontrolled cell division and proliferation, and it results in death in many organisms. Doxorubicin (DOX) is a therapeutic agent used for treatment of many cancer types, but it induces serious hepatotoxicity. In this study, we aimed to determine possible hepato-therapeutic effects of thymoquinone (THQ) on DOX-induced hepatotoxicity in rats. Rats were divided into five groups (n = 8): Control, THQ (10 mg/kg/day/i.p for 14 days), Olive Oil (equal volume with THQ for 14 days), DOX (single dose, 15 mg/kg/i.p on 7th day) and DOX + THQ (10 mg/kg/day/i.p and DOX 15 mg/kg/i.p on 7th day). At the end of the experiment, liver tissues were extracted and evaluated histopathologically. eNOS, iNOS and Cas-3 immunostaining were performed to determine the expression levels. TUNEL method was used to determine apoptotic index. Furthermore, liver tissue total antioxidant status (TAS), total oxidant status (TOS), TNF-α and TGF-β levels were measured by ELISA assay. The DOX group showed histopathological deterioration compared to Control group. Moreover, apoptotic index, eNOS, iNOS and Cas-3 expressions increased in DOX group. While TAS level of the DOX group decreased, TOS level increased. TNF-α and TGF-β levels increased in DOX group. However, there was improvement in DOX + THQ group compared to DOX group. Moreover, apoptotic cell number, eNOS, iNOS and Cas-3 expressions decreased in DOX + THQ group compared to DOX group. We concluded that thymoquinone can be used as a phytotherapeutic for reducing DOX-induced liver damage. 相似文献
135.
Christopher W. Hunt Theodore Loder III Charles VÖrÖsmarty 《Water, air, and soil pollution》2005,163(1-4):303-323
A catchment-wide study was conducted to investigate the geography of nutrient dynamics in the Androscoggin and Kennebec Rivers, Maine. While nutrient concentrations resembled relatively pristine waters, nitrogen (N) and phosphorus (P) exhibited dramatic spatial and temporal patterns. Though these rivers are underdeveloped, impacts of human activities upon nutrients are clear. Population was a good predictor for DIN and P concentrations for the Kennebec River, but a poor predictor in the Androscoggin River. Comparison of point-source discharges into each river indicated that the Androscoggin River is influenced by discharges from pulp and paper mills, a finding confirmed by reduced nutrient transport after the closure of two Androscoggin River mills. Nutrient ratio analysis demonstrated a dramatic shift towards Redfield ratios, with DIN:P ratios decreasing from about 200:1 in headwater reaches to below 16:1 near the river outlets. These results may aid in understanding blooms of toxic dynoflagellates in the Gulf of Maine. Ratios were also altered during a prolonged drought period. Results describe a simple relationship between increased nutrient input and human population within single watersheds, with implications for coastal zone ecosystems. 相似文献
136.
ABSTRACT In this study, the effect of the depuration period on proximate composition, metals, fatty acids, and bacteria in the edible tissue of warty venus (Venus verrucosa) collected from ?zmir Bay in the Aegean Sea was investigated. In addition, benefit and risk for human health associated with the consumption of warty venus were determined by atherogenic index (AI), thrombogenic index (TI), polyene index (PI), fish lipid quality (FLQ), target hazard quotient (THQ), and hazard index (HI). The depuration process did not show a significant (P > .05) effect on proximate composition, except for ash. The depuration process was successful in reducing bacteria growth and the concentrations of all metals, except for copper. Total aerobic mesophilic bacteria count of 1.94 log CFU/g in the fresh samples was uncountable at 24 h of depuration. The concentrations of cadmium, lead, copper, iron, and zinc were below the limit values allowed for safe consumption. The analyzed metals were safe for human consumption based on provisional tolerable weekly intake (PTWI), THQ, and HI. Significant variations were also observed in the fatty acid values depending on the depuration periods (P < .05). The n3/n6 and polyunsaturated/saturated fatty acid ratios were greater than those recommended by the FAO/WHO. Moreover, the AI and TI of samples were under established limits. 相似文献
137.
The surveys of natural gamma-emitting radionuclides and 137Cs in surface soils of coniferous forest sites in and around Izmir were conducted during 2003?C2004. The soil samples were collected from three different depths of 15 forest sites, particularly local wild edible mushrooms areas. The average activity concentrations and ranges of the natural radionuclides in the soils were as follows: 30 (14?C51) Bq kg?1 of 226Ra; 40 (17?C79) Bq kg?1 of 232Th; and 581 (308?C879) Bq kg?1 of 40K. Moreover, the values of 137Cs activity concentrations averaged over the depth sections varied from 20 to 82 Bq kg?1 with a mean value of 52 Bq kg?1. Accordingly, the levels of the studied natural radionuclides in the forest soils were within the range specified by UNSCEAR (2000) report for regular soils as well as the agricultural soils from the West Anatolia, while the measured activity levels of 137Cs in the forest soils were still high in contrast to agricultural soils after 16 years from the deposition of Chernobyl fallout. 相似文献
138.
Jacobson Staffan Högbom Lars Ring Eva Nohrstedt Hans-Örjan 《Water, air, and soil pollution》2004,158(1):113-125
Harvesting stem biomass from the forest inevitably involves exporting nutrients from the ecosystem. The amount exported is increased when the logging residues are also removed for use as fuel. Recycling of the resulting wood ash has been advocated as a measure to compensate for the nutrient losses and to sustain future forest production. The physical formulation of the wood ash may have an important influence on its effects on soil properties. In this paper, we report effects of two different types of wood ash (one self-hardened and crushed, the other pelleted), with differences in solubility, on soil chemistry in the humus layer and upper 15 cm of the mineral soil, at two coniferous sites in south-central Sweden, 5 yr after their application. The crushed ash was applied at three doses (3, 6 and 9 ton ha–1), while the pelleted ash was applied at only one dose (3 ton ha–1). At both sites the soil was podzolized. The two sites differed with respect to soil conditions, despite being situated only a few kilometers apart. The application of wood ash increased both soil pH and base-cation content in the humus layer at both sites. In the mineral soil, the effects were less pronounced. Treatment effects on soil chemistry did not differ between the two ash formulations. The retention (i.e. the extractable amount of nutrients found in the soil that could be attributed to the ash application) of nutrients varied strongly between the two sites, and K retention (ca. 10%) was generally lower than that of Ca and Mg. 相似文献
139.
Water, Air, &; Soil Pollution - The hydrochemical study of the area surrounding the Hisarc?k (Emet-Kütahya) colemanite mine shows extremely high arsenic contamination in ground water... 相似文献
140.
SW Sweden has very acidic forest soils because of deposition ofair-borne pollutants. Large-scale liming and fertilization have been proposed as countermeasures against a possible future development of forest decline. To test the effects of suggested treatments, liming (3 or 6 t ha1) and fertilization with easily soluble PK (25 or 50 kg P, 80 or 160 kg K ha1) or N(20 kg N ha1 annually in the form of NH4 NO3) were applied in different combinations in four experiments in 30–60 yr-old Picea abies forests in SW Sweden. Four yearsafter the initial application of the fertilizers, samples were taken from the O-horizon and the two uppermost 5 cm thick layersof the mineral soil. Their pH(H2O) and easily extractable Ca, Mg, K, P and inorganic N contents were analyzed. Samples werealso incubated to estimate net N mineralization and potential nitrification rates. Liming increased the pH by 0.6–1 unit in the O-horizon, and by 0.1 unit in the mineral soil. The Ca + Mg content increased by 15–25 kmolc ha1 (4–8 foldincrease) in the O-horizon of the limed plots, while an increaseof 5 kmolc ha1 (two-fold increase) was observed in theuppermost 5 cm of the mineral soil. Liming did not affect extractable P, K or inorganic N contents. Net N mineralization and potential nitrification rates in the O-horizon were enhanced 1.5- and 6-fold, respectively, by liming, but it had no apparenteffect in the mineral soil. N fertilization caused a slight increase (1.5 kg ha1) in the content of inorganic N, buthad no effects on the other variables measured. The amount ofextractable P was raised by 16 kg ha1 in plots given the high P dose (50 kg ha1), but no other effects of PK fertilization were detected. 相似文献