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91.
Monthly variations in meat yield and biochemical composition of Mediterranean mussels on lantern nets were investigated from May 2005 to May 2006, in Sinop, south of the Black Sea. Dry weight condition index was between 2.66 and 7.10% with a mean of 4.86 ± 0.36%. Meat yield was maximum (26.69%) in March and minimum (17.43%) in October. Moisture values were between 78% (in June) and 86% (in April). Protein content in dry weight of mussels reached the highest value in February (74.64%) before the spawning time. Lipid value was maximum (18.03%) in May 2005.  相似文献   
92.
ABSTRACT

The present study evaluated the effect of whey protein isolate (WPI) coating enriched with thyme essential oil (EO; 3, 5, and 7%, v/v) on whole trout chemical and microbial quality during refrigerated storage at 4 ± 2°C. As a result of this study, the addition of thyme essential oil to WPI coatings enhanced quality significantly better than that of the control and WPI coating without thyme essential oil during refrigerated storage, and this effect increased with an increase in the thyme EO concentration in WPI coating.  相似文献   
93.
Study of Biodegradation Processes of BTEX-ethanol Mixture in Tropical Soil   总被引:1,自引:0,他引:1  
In Brazil, gasoline is currently blended with ethanol and both compounds may contaminate the environment when spills occur. Ethanol preferential biodegradation delays gasoline degradation in the aquifer, as previously observed; in unsaturated soil a delayed recovery of culturable bacteria and removal of residues in the presence of ethanol suggest a similar situation. This study monitors microbial degrading activity in unsaturated soil with BTEX and BTEX-ethanol mixtures under tropical conditions as well as the effects of bioventing on contaminants degradation. Enzymatic activity was quantified by measuring fluorescein-diacetate hydrolysis by microorganisms, which determines total degrading activity in soil. As microbial enhanced activity may alter soil electromagnetic properties, soil dielectric constant shifts were monitored using Time Domain Reflectometry (TDR), while chemical analyses evaluated contamination residues throughout the experiment. Results suggest that ethanol delays BTEX biodegradation and that bioventing may compensate for this delay by providing oxygen for the continuation of microbial activity. Contamination and bioventing stimulated soil microbiota, while culturable populations were inhibited by contamination, showing soil toxicity. The presence of ethanol caused a higher and longer-lasting boost in enzymatic activity; TDR measurements did not follow these activity shifts, proving not to be an adequate tool for evaluating microbial activity in these experimental conditions. Residual BTEX were detected only in ethanol-containing non-ventilated soils after contamination. The set of results suggests that ethanol could delay BTEX degradation because of its constitutive degradation by soil microbiota, but this effect may be bypassed by bioventing.  相似文献   
94.
95.
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   
96.
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   
97.
The present study investigated the antifungal effects of essential oils of oregano (Origanum onites) and laurel (Laurus nobilis) on Saprolegniasis, a disease that occurs in rainbow trout eggs during the incubation period. Oregano and laurel were ground after drying, and essential oils were obtained by water distillation method using a Clevenger apparatus. The essential oils were added to potato dextrose agar (PDA) at the rates of 1–1000 ppm, and the minimum inhibitory concentration (MIC) was determined as 250 ppm whereas the minimum lethal concentration (MLC) was determined to be 500 ppm for both plants. In the in vivo trials, fertilized eggs were treated with predetermined doses either by bathing during water hardening and incubation period or only during incubation period, and death rates were monitored during embryological development. The best larvae hatching rate was determined in 500 ppm oregano and 500 ppm laurel groups treated during water hardening plus daily as 82.11% and 79.87%, respectively. According to the results, it was determined that oregano and laurel essential oils exhibited better results in all doses compared with the negative control group, and 500 ppm dose had a better effect than the positive control group treated with formalin.  相似文献   
98.
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   
99.
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   
100.
Objectives : The objective of this study was to evaluate the surgical times for removal of ovaries, and the frequency of intra‐operative complications with two different instruments used for canine laparoscopic ovariectomy. Methods : A randomised prospective clinical study. Laparoscopic ovariectomy was performed under general anaesthesia on 10 healthy female dogs admitted for elective ovariectomy. Each ovary was randomly assigned to removal by use of either a SonoSurg? ultrasonic surgical device (Olympus), or a LigaSure? vessel‐sealing system (Valleylab/Covidien). Surgical time for removal of each ovary was measured and the frequency of intra‐operative complications was recorded. A follow‐up was made by interview with the owners, 2·5 years after surgery. Results : The two techniques did not statistically differ with regard to surgical time, or frequency of complications. All owners were very satisfied with the procedure. Clinical Relevance : Both the SonoSurg? and the LigaSure? devices appear to be effective, safe and easy to use when performing laparoscopic ovariectomy in dogs.  相似文献   
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