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61.
Environmental Science and Pollution Research - This study aimed to investigate the effect of exposure to pesticides and the prevalence of type 2 diabetes (T2D). In a cross-sectional study with a...  相似文献   
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63.

Fish protein hydrolysates are digested form of protein with various bioactive properties where, the cleavages of molecular bonds of proteins can be broken by the enzymatic and chemical process. In this study, antioxidant properties of spray dried protein hydrolysate prepared from Pangasius viscera by using enzymatic (papain and pepsin), and chemical methods (hydrochloric acid and sodium hydroxide) were evaluated. Among the different treatments, pepsin-derived visceral protein hydrolysate showed the maximum antioxidant activity when used at higher concentrations. Essential amino acids (EAA) and hydrophobic amino acids are higher in papain-derived visceral protein hydrolysate. In pepsin-derived visceral protein hydrolysate, major proportion was contributed by glycine (Gly), glutamine (Glu), proline (Pro), and asparagine (Asp). Higher amount of aromatic amino acids are found in alkali-derived FVPH. Scanning electron microscopy (SEM) images of pepsin fish visceral protein hydrolysate showed better globular structure than the other treatments. It can be concluded that among the different treatments, the visceral protein hydrolysate prepared with pepsin had better overall quality regarding antioxidant properties and papain in nutritional point of view.

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64.
Scleractinian coral species harbour communities of photosynthetic taxa of the genus Symbiodinium. As many as eight genetic clades (A, B, C, D, E, F, G and H) of Symbiodinium have been discovered using molecular biology. These clades may differ from each other in their physiology, and thus influence the ecological distribution and resilience of their host corals to environmental stresses. Corals of the Persian Gulf are normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. This study is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs to the level of phylogenetic clades. Samples of eight coral species were collected at two different depths from the eastern part of Kish Island in the northern Persian Gulf, and Larak Island in the Strait of Hormuz. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by polymerase chain reaction (PCR). PCR products were analyzed using single stranded conformational polymorphism and phylogenetic analyses of the LSU DNA sequences from a subset of the samples. The results showed that Symbiodinium populations were generally uniform among and within the populations of eight coral species studied, and there are at least two clades of Symbiodinium from Kish and Larak islands. Clade D was detected from eight of the coral species while clade C was found in two of species only (one species hosted two clades simultaneously). The dominance of clade D might be explained by high temperatures or the extreme temperature variation, typical of the Persian Gulf. Publication of this article was held up owing to technical problems. The publisher apologizes sincerely for this lengthy delay.  相似文献   
65.
Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses, which are considered as one of the major sources of this gas in indoor environment, have been studied for exhalation rate of radon. Non-nuclear industries, such as coal fired power plants or fertilizer production facilities, generate large amounts of waste gypsum as by-products. Compared to other building materials waste gypsum from fertilizer production facilities (phosphogypsum) shows increased rates of radon exhalation. In the present, investigation solid state alpha track detectors, CR-39 plastic detectors, were used to measure the indoor radon concentration and the radon exhalation rates from some building materials used in Egypt. The indoor radon concentration and the radon exhalation rate ranges were found to be 24–55 Bq m−3 and 11–223 mBq m−2 h−1, respectively. The effective dose equivalent range for the indoor was found 0.6–1.4 mSv y−1. The equilibrium factor between radon and its daughters increased with the increase of relative humidity.  相似文献   
66.
The residues of 17 organochlorine pollutants were analyzed in bivalve Brachiodontes sp. collected from 11 different locations in April 2000 along the Egyptian Red Sea coast. The pollutants studied were 10 individual polychlorinated biphenyl (PCB) congeners, alpha,alpha,alpha-hexachlorocyclohexane (HCHs), cyclodienes (heptachlor, heptachlorepoxide, aldrin, dieldrin) and dichlorodiphenyltrichloroethanes (DDTs) (p,p'-DDE, p,p'-DDD and p,p'-DDT). The concentration of total DDTs ranged between 125 and 772 ng/g of wet weight whereas the concentration of the PCBs, HCHs and cyclodienes ranged from 6.7 to 66.4 ng/g; 16.2 to 183.4 ng/g and 8.8 to 221.6 ng/g of wet weight, respectively. The levels are low to moderate in relation to the published data from other coastal areas. The present results indicate low to moderate PCBs and pesticides contamination in the investigated mussels except DDTs.  相似文献   
67.
In vivo chronic effect of dimethoate and deltamethrin on rabbits   总被引:1,自引:0,他引:1  
The in vivo effect of dimethoate and deltamethrin on body and organ weights, serum proteins and on plasma acetylcholinesterase (AChE), aromatic esterase and ATPase were examined in growing male rabbits throughout five months period. Both compounds had no significant effect on body weight; however, adrenal, testis & pituitary weights decreased (P less than 0.01); the liver and spleen weights increased (P less than 0.01) in a dose dependent manner. Serum total proteins and globulin decreased (P less than 0.01) in a dose dependent trend, while serum albumin was not greatly affected. AChE activity was increased (P less than 0.01) after 1 month of treatment with the two doses of dimethoate and deltamethrin; thereafter, AChE activity showed 40% inhibition of the control level. The activity of aromatic esterase increased markedly after the first month, then declined gradually until the fifth month. High dose of dimethoate markedly inhibited this enzyme particularly after the 5th month of treatment. Both doses of deltamethrin increased ATPase activity after the first month of treatment, then the ATPase activity was normal. Dimethoate inhibited ATPase particularly at the end of treatment in a dose dependent manner.  相似文献   
68.
Water and sediment samples were collected from eight different locations along the River Nile and its branches. Residues of hexachlorocyclohexane (HCH's), hexachlorobenzene (HCB), DDT's, cyclodienes and polychlorinated biphenyls (PCB's) were analyzed by GLC. Data on Grand Total (GT) concentration values pointed out that Rosetta Branch was more polluted with all components than Demietta Branch. Kafr El-Ziate was the most polluted location showing 1355.8 ng/L for water and 7396.9 ng/g for sediments, while Delta Barrage was the least polluted site. The concentrations of gamma-HCH were higher than the other isomers (alpha- and beta-HCH) in all studied sites. The results showed that HCB was the smallest pollutant at all locations on comparison with other chlorinated hydrocarbons. El-Mansoura, Rosetta and Kafr El-Ziate sites contained the highest concentrations of DDT's in both water and sediment samples. P,P'-DDE was dominate in all locations of water samples, but P,P'-DDT was in sediment samples. Also, the results showed the prominent presence of cyclodienes when compared with the other OC's compounds in sediment samples, especially Aldrin. Kafr El-Ziate was the most polluted location by PCB's, particularly the Ar1242. However, there were increasing levels of chlorinated hydrocarbons in the sediment samples parallel to percentage extractable organic matter (% EOM). Sediment/water ratios were calculated for all locations.  相似文献   
69.
Yacob S  Hassan MA  Shirai Y  Wakisaka M  Subash S 《Chemosphere》2005,59(11):1575-1581
Anthropogenic release of greenhouse gases, especially CO2 and CH4 has been recognized as one of the main causes of global warming. Several measures under the Kyoto Protocol 1997 have been drawn up to reduce the greenhouse gases emission. One of the measures is Clean Development Mechanisms (CDM) that was created to enable developed countries to cooperate with developing countries in emission reduction activities. In Malaysia, palm oil industry particularly from palm oil mill effluent (POME) anaerobic treatment has been identified as an important source of CH4. However, there is no study to quantify the actual CH4 emission from the commercial scale wastewater treatment facility. Hence, this paper shall address the CH4 emission from the open digesting tanks in Felda Serting Hilir Palm Oil Mill. CH4 emission pattern was recorded for 52 weeks from 3600 m3 open digesting tanks. The findings indicated that the CH4 content was between 13.5% and 49.0% which was lower than the value of 65% reported earlier. The biogas flow rate ranged between 0.8 l min−1 m−2 and 9.8 l min−1 m−2. Total CH4 emission per open digesting tank was 518.9 kg day−1. Relationships between CH4 emission and total carbon removal and POME discharged were also discussed. Fluctuation of biogas production was observed throughout the studies as a result of seasonal oil palm cropping, mill activities, variation of POME quality and quantity discharged from the mill. Thus only through long-term field measurement CH4 emission can be accurately estimated.  相似文献   
70.
El Nemr A  Abd-Allah AM 《Chemosphere》2003,52(10):1711-1716
The residues of seven polycyclic aromatic hydrocarbons (PAHs) pollutants in microlayer and subsurface seawater samples collected from Alexandria coast, Egypt, were analyzed by gas chromatography–electron-impact mass spectrometry-selected ion monitoring mode (GC–MS-SIM). The pollutants studied were, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene and benzo[a]pyrene. Total PAH levels in microlayer ranged from 103 to 523 ng/l, while it ranged in subsurface samples from 13 to 120 ng/l. The Western Harbor location recorded the highest level of PAHs pollutant over all the other location for both subsurface and microlayer waters. The two major PAHs in microlayer water at the Western Harbor were fluorene and phenanthrene, making up 27% and 20% of the total PAHs, while the two major PAHs in subsurface water at the Eastern Harbor were phenanthrene and fluoranthene recording up 21% each of the total PAHs. The total PAH levels were generally in the nano-gram per liter for microlayer and subsurface seawater samples. The dominant PAHs in both subsurface and microlayer samples were fluoranthene, pyrene and benzo[a]pyrene. The microlayer enrichment factor at Alexandria’s Mediterranean coast was ranged from 29 for fluorene to 3 for phenanthrene and benzo[a]pyrene which showed PAHs concentration in the microlayer with an average of five times more than the total PAH in the subsurface samples.  相似文献   
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