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991.
Ali A. Z. Douabul Hamid T. Al-Saad Selma Z. Al-Obaidy Hussain N. Al-Rekabi 《Water, air, and soil pollution》1987,35(1-2):187-194
High-resolution electron capture gas chromatography was used to determine residue levels of organochlorine pesticides in 13 commercially important fish species collected from the NW Arabian Gulf. While most of the residues were below the detection limit of 1 μg kg?1 wet weight, relatively low concentrations of ΣDDT, endrin and dieldrin were detected in the edbile tissue of these fishes. The ΣDDT residue levels ranged from 2 to l 1μg kg?1 wet weight, endrin ranged from none detected (nd) to 45 μg kg?1 and dieldrin from nd to 5 μg kg?1. A definite correlation was established between total organochlorine pesticide residues and lipid content (r = 0.6) for the NW Arabian Gulf fishes. Comparison with fish from Hor-al-Hammar Lake (an area that used to be sprayed with pesticides) has shown that the latter contained significantly higher residue levels. The ΣDDT residue levels ranged from 5 to 45 μg kg?1 wet weight, endrin from 3 to 83 μg kg?1 and dieldrin from nd to 4 μg kg?1 Based upon the observation that the original DDT (p, p′-DDT) was identified in the NW Arabian Gulf fishes, it has been concluded that there was a recent input of DDT to this region. Since DDT application has been banned in Iraq, consequently it was assumed that DDT must originate from a more remote source. 相似文献
992.
Javad Sadeghinezhad Zahra Ganji Sirous Sadeghian Chaleshtori Hadis Bojarzadeh Mahdi Aghabalazadeh Asl Ali Bayat Khomejini Ehsan Roominai Mohsen Hosseini Margherita De Silva 《Anatomia, histologia, embryologia》2021,50(6):1026-1033
Sheep have been used as translational models of human postnatal testicular development. However, the morphometric features of the normal developing testis in sheep embryos have not been previously investigated using stereology. The objective of the present work was to establish normal quantitative parameters for fetal testicular tissue components in sheep, using unbiased design-based stereological methods. Twenty-four sheep embryos were divided into four gestational age groups (9–11, 12–14, 15–17 and 18–20 weeks of gestation) on the basis of the embryos’ crown-rump length. Isotropic, systematic uniform random sections of the left testes were obtained by employing the orientator method. Testicular total volume, the absolute and proportional volumes occupied by the seminiferous tubules and interstitial tissue, as well as the seminiferous tubule length, were estimated using the point-counting system and the unbiased counting frame principle. All the parameters, with the exception of the interstitial tissue's fractional volume, gradually increased along with gestational age, with the maximum increase especially seen in the late fetal stages. The proportional volume of the interstitial tissue, on the other hand, showed a decreasing trend along with increasing gestational age. The absolute volume of the testes, of the seminiferous tubules and of the interstitial tissue, and the length of the seminiferous tubules showed a significant (p< 0.05) positive linear correlation with gestational age. Several similarities were observed with human testicular embryogenesis. The stereological data emerging from the present study might prove useful as basic contribution to the fields of andrology and embryology and stimulate further research in these areas. 相似文献
993.
Poll glands are characteristic feature of dromedary camels; although they yield a yellowish offensive secretion, especially during rutting (breeding) season, their function is not yet exactly specified. The present study shows the seasonal morphology and immunoreactivity of cytokeratin (CK) and atrial natriuretic peptide (ANP) in the camel poll gland; the result could clearly specify the role of the gland in camel reproduction. Poll glands are compound tubulo-alveolar in structure. During rutting season, the secretory units showed wide lumina and simple squamous epithelium surrounded by myoepithelial cells; the lumina became narrower and the epithelium changed to simple cuboidal during non-rutting season. Many glandular lobules showed abundant interlobular connective tissue with fewer and smaller secretory units during non-rutting season compared to rutting season. Positive CK and ANP immunoreactivity was detected in the cytoplasm of epithelial cells of secretory units and ducts together with the myoepithelial cells and blood vessels. Although CK immunoreactivity was more intense during rutting season in comparison to non-rutting season, there was no seasonal variation in ANP immunoreactivity. During both seasons, while the glandular capsule, connective tissue septa, interstitium showed negative CK immunoreactions, they reacted moderately to ANP. In conclusion, the poll gland undergoes annual structural and functional changes which are suggested to correlate with the male seasonal sexual behaviour. Further, the biological role of CK and ANP proteins together with their immunohistochemical expression in the camel poll gland suggests a stimulatory effect in the glandular secretory cells, and hence, they might modify camel sexual activity. 相似文献
994.
Ali Osman Demir Abdurrahim Tanju Göksoy Hakan Büyükcangaz Zeki Metin Turan Eyüp Selim Köksal 《Irrigation Science》2006,24(4):279-289
The response of sunflower (Helianthus annuus L.) to 14 irrigation treatments in a sub-humid environment (Bursa, Turkey) was studied in the field for two seasons. A rainfed (non-irrigated) treatment as the control and 13 irrigation treatments with full and 12 different deficit irrigations were applied to the hybrid Sanbro (Novartis Seed Company) planted on clay soil, at three critical development stages: heading (H), flowering (F) and milk ripening (M). The yield increased with irrigation water amount, and the highest seed yield (3.95 t ha−1) and oil yield (1.78 t ha−1) were obtained from the HFM treatment (full irrigation at three stages); 82.9 and 85.4% increases, respectively, compared to the control. Evapotranspiration (ET) increased with increased amounts of irrigation water supplied. The highest seasonal ET (average of 652 mm) was estimated at the HFM treatment. Additionally, yield response factor (k
y) was separately calculated for each, two and total growth stages, and k
y was found to be 0.8382, 0.9159 (the highest value) and 0.7708 (the lowest value) for the total growing season, heading, and flowering-milk ripening combination stages, respectively. It is concluded that HFM irrigation is the best choice for maximum yield under the local conditions, but these irrigation schemes must be re-considered in areas where water resources are more limited. In the case of more restricted irrigation, the limitation of irrigation water at the flowering period should be avoided; as the highest water use efficiency (WUE) (7.80 kg ha−1 mm−1) and irrigation water use efficiency (IWUE) (10.19 kg ha−1 mm−1) were obtained from the F treatment. 相似文献
995.
禾豆混播与调亏灌溉对河西地区饲草产量、品质和水分利用的影响 总被引:1,自引:0,他引:1
本研究于2019年在河西地区设置青贮玉米(Zea mays)单播(Z)、青贮玉米–秣食豆(Glycine max)混播(ZG)和青贮玉米–拉巴豆(Dolichos lablab)混播 (ZD) 3个种植方式,每个方式下设置 6种灌溉模式,研究不同种植方式和灌溉模式对饲草产量、品质和水分利用效率的影响。结果表明:1) ZG和ZD的鲜干草产量显著(P < 0.05)高于Z,鲜草产量较Z分别增加19.1%和16.4%,干草产量分别增加12.7%和9.0%。同一种植方式下,后期轻度亏水(I4)、前期轻度亏水(I5)和充分灌溉处理(I6)的鲜干草产量显著(P < 0.05)高于重度亏水(I1),平均鲜草产量较I1分别增加39.1%、45.9%和46.6%,平均干草产量较I1分别增加35.8%、44.2%和43.8%。2) 混播处理较单播提高粗蛋白含量,明显降低淀粉、酸性和中性洗涤纤维含量,进而提高相对饲用价值(RFV),且ZG较Z显著(P < 0.05)增加粗蛋白、粗脂肪和粗灰分的产量。I5的平均粗蛋白、粗脂肪含量和RFV显著(P < 0.05)高于I1,6种灌溉模式中I5的粗蛋白、淀粉、粗脂肪和粗灰分的产量最高。3) ZG和ZD较Z显著提高(P < 0.05)水分利用效率(WUE)。I5和I6的收获期土壤贮水量和蒸散量显著(P < 0.05)高于I1,且I5的WUE显著(P < 0.05)高于I4和I6。所有处理中ZG-I5的WUE以及粗蛋白、粗脂肪和淀粉的产量最高,并且鲜干草产量仅次于ZG-I6,该处理是适宜河西地区青饲玉米生产的栽培模式。 相似文献
996.
Abstract – To assess the consequences of unpredictability in the availability of food, this study measured the effect of timing of the daily feeding on food consumption and growth rates of juvenile Gasterosteus aculeatus. The experiment lasted 21 days at 14 °C and a photoperiod of 10 hours of light and 14 hours of dark. Fish were housed individually and allocated at random to three treatments. The mean initial weight of fish was 0.402 g. Group 1 were fed live enchytraeid worms for 2 h after lights came on ("morning"), group 2 was offered food for 2 h randomly at any time of the day ("random") during the light period and group 3 received food for 2 h before the lights went off ("evening"). There was no significant effect of timing of feeding on mean daily food consumption, which was 0.052 g day−1 . Daily consumption on the random schedule was more irregular than on the two fixed schedules. Timing of feeding had no significant effect on mean specific growth rate (G) (2.42% day−1 ), gross growth efficiency (23.3%), white muscle RNA:DNA ratio (5.6), carcase lipid content (31.7% dry wt) and carcase dry matter content (27.4% wet wt). Thus, a lack of predictability in the availability of food during the light period of the day did not impose a detectable cost on the growth performance of the stickleback. 相似文献
997.
Effect of low level of dietary aflatoxins on baladi rabbits 总被引:1,自引:0,他引:1
A M Abdelhamid I el-Shawaf S A el-Ayoty M M Ali T Gamil 《Archives of Animal Nutrition》1990,40(5-6):517-537
Aflatoxins B1, B2, G1 & G2 were administered in a low concentration (100 ppb of each aflatoxin (AN] in a mash offered to Baladi rabbits. An other group of rabbits were fed on the same contaminated mash in addition to 0.25% charcoal (CC). The two groups were compared to control animals fed on AN-free mash. Inclusion of AN in the diet decreased feed and water consumption, body weight and survival rate. Charcoal improved somewhat feed and water consumption and growth rate than AN-group. However, CC-group affected digestibility of organic matter more than AN-group. Relative weights of liver, kidneys, heart and adrenal glands were significantly higher in AN and CC groups than the control group. Blood haemoglobin content, packed cell volume percentage and sedimentation rate were lower in AN group. Although there were an increase in each of serum, calcium, inorganic phosphorus, cholesterol, phospholipids and glutamic-pyruvic transaminase in AN group, yet the serum nitrogen and glutamic-oxalacetic transaminase were reduced. Charcoal had alleviated AN-effects concerning N, GPT and phospholipids. Chemical analysis revealed elevation of water, ash and silica contents of liver and water content of muscles from AN-animals. On the other hand, fat content, GOT and vitamin A in the liver as well as muscles ash were reduced. Addition of CC to the diet reduced AN-effects on liver fat, ash and silica but resulted in a rise of the water content of liver and muscles and liver GPT activity. Charcoal also resulted in a sharp decrease in vitamin A content of the liver. Aflatoxin treatments (in AN and CC groups) reduced bone ash, silica and magnesium as well as bone volume. Charcoal administration increased Ca-content of bones. Aflatoxin feeding (in AN group) resulted in a high residual percentage of AN in muscles, serum, liver, heart and kidneys with relationships of 51 :24 : 3 :2 : 1, respectively. Only 1.42% of the fed AN was excreted in the faeces. Charcoal usage had a good effect as it prevented AN to accumulate in the organs. Aflatoxin contaminated diets (in AN and CC groups) resulted in paralysis, disorder of fat deposition, discolouration and haemorrhages of some organs. Scanning electron microscopic examination revealed no ill effect on the surface structure of the small intestine due to either AN or AN + CC. Pathological examination showed that the main affected organs were liver, heart and spleen, respectively. The changes include hepatic round cell infiltration, irregularities of lobular plats, focal necrosis and periportal fibrosis.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
998.
Wilson FH Hariri A Farhi A Zhao H Petersen KF Toka HR Nelson-Williams C Raja KM Kashgarian M Shulman GI Scheinman SJ Lifton RP 《Science (New York, N.Y.)》2004,306(5699):1190-1194
Hypertension and dyslipidemia are risk factors for atherosclerosis and occur together more often than expected by chance. Although this clustering suggests shared causation, unifying factors remain unknown. We describe a large kindred with a syndrome including hypertension, hypercholesterolemia, and hypomagnesemia. Each phenotype is transmitted on the maternal lineage with a pattern indicating mitochondrial inheritance. Analysis of the mitochondrial genome of the maternal lineage identified a homoplasmic mutation substituting cytidine for uridine immediately 5' to the mitochondrial transfer RNA(Ile) anticodon. Uridine at this position is nearly invariate among transfer RNAs because of its role in stabilizing the anticodon loop. Given the known loss of mitochondrial function with aging, these findings may have implications for the common clustering of these metabolic disorders. 相似文献
999.
Mohaddeseh A. Tabari Mohammad Reza Youssefi Seyed Mehdi Hosseinifard Ali Akbar Moghaddamnia Sohrab Kazemi NadAli Yousefi Sadati Azadeh Jalali Mothahari Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2020,43(3):276-281
The pharmacokinetic parameters of levamisole were determined in the Caspian salmon after intramuscular (IM), oral by gavage, and oral by feed administrations. Eighty-one healthy fish in three different groups received levamisole at the dose of 25 mg/fish by each route. Blood samples were collected at time points of 0, 0.5, 1, 2, 4, 6, 12, 14, and 24 hr after administrations. Plasma levamisole concentrations were measured by a validated high-performance liquid chromatography (HPLC) assay and were analyzed using a noncompartmental approach. The mean terminal half-life was 4.56, 3.95, and 2.91 hr for IM, gavage and feed routes, respectively. The peak plasma concentration for IM, gavage, and feed routes of levamisole were 35.53, 4.63, and 8.36 µg/ml, respectively, at the time of 0.25 for IM, and 1 hr for gavage and feed. The relative bioavailability for gavage and feed routes was 54.80 and 69.30. The similar bioavailability for gavage and feed might be indicative of similar efficacy for these routes of administrations. Further studies are warranted to evaluate the absolute oral bioavailability and the effective dose in Caspian salmon. 相似文献
1000.
Sadeghi Seyed Abu Taleb Rokouei Mohammad Valleh Mehdi Vafaye Abbasi Mokhtar Ali Faraji-Arough Hadi 《Tropical animal health and production》2020,52(2):733-742
Tropical Animal Health and Production - Non-additive genetic effects are important to increase the accuracy of estimating genetic parameters for growth traits. The aim of this study was to estimate... 相似文献