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161.
Mansour Aboelenain Wael B. El_domany Haitham Eldoumani Wael A. Khalil 《Reproduction in domestic animals》2020,55(8):1021-1024
Increased reactive oxygen species (ROS) generation may disrupt the oocytes function and their competence. In this study, we introduced BTZO-1, a new supplement that can regulate the oxidative stress. Addition of BTZO-1 during IVM of bovine oocytes improved their developmental competence in the term of improvement of blastocyst rates. In addition, the quality of the produced embryos was improved by decreasing the apoptosis level by showing a decreased number of TUNNEL positive cells. 相似文献
162.
Ramadan G. Sary Ragab H. Mohamed Karim M. Khalil Al-Lethie A. Al-lethie Hassan A. Hussein 《Reproduction in domestic animals》2020,55(3):343-350
The current study aimed to investigate the effect of testicular artery angioarchitecture on the spermiogram parameters in Egyptian Buffalo bulls. Eight adult buffalo bulls aged between 2 and 8 years were used for semen evaluation. For anatomical studies, the masculine gonads were collected after slaughtering 30 adult bulls and prepared for injection by different masses (Urographine®, Latex and Epoxy) through the testicular artery. The mass activity of the ejaculate was assessed immediately after collection. The sperm motility in fresh bull ejaculate was more than 80%. The overall mean percentage of sperm abnormalities was <18%. The recorded sperm abnormalities were mostly secondary one including distal protoplasmic droplet, fragmented tail, detached head, detached galea capitis and bent tail. The highest percentage of sperm viability was recorded just after sperm collection (alive > 85%). The results revealed that testicular artery can be divided into three parts (abdominal, funicular and marginal parts) along its course. The coils of the funicular part forming a cone-like structure with its base fixed to the head of the testis. Two epididymal branches to the head and tail of epididymis emanate from the funicular part which continues as pars marginalis on the lateral surface of testis before its division into the lateral and medial testicular arteries on approaching the tail extremity of the testis. The increase in the length of the testicular artery with increase in the size of the testes played a great role in the degree of complexity of the architectural vascular patterns. The degree of complexity is affected by the number of coils formed by the vessel. The increase in the convolutions of the vessel will reduce the speed of blood flow to the gonads. Thus in turn will enabling the thermoregulatory mechanism to work more efficiently and will affect the semen value. 相似文献
163.
Anwar F Bhanger MI Nasir MK Ismail S 《Journal of agricultural and food chemistry》2002,50(15):4210-4214
Seeds of Salicornia bigelovii (hybrid variety sos-10) were collected from five coastal areas of Pakistan on the Arabian Sea. Hexane-extracted oil content was 27.2-32.0%. Results of other physical and chemical parameters of the extracted oil were as follows: iodine value, 128.0-130.5; refractive index (40 degrees C), 1.4680-1.4695; unsaponifiable matter, 1.63-2.00%; saponification value, 178.6-189.0; density (30 degrees C), 0.9036-0.9074. Tocopherols (alpha, gamma, and delta) in the oil ranged up to 200 mg/kg. The S. bigelovii seed oil was found to contain high levels of linoleic acid (74.66-79.49%) and less oleic acid (12.33-16.83%). Saturated fatty acids, palmitic and stearic acids, ranged from 7 to 8.50% and from 1.24 to 1.69%, respectively. Linolenic acid (C(18:3) omega-3) was found within the range of 1.50-2.31%. The induction period (Rancimat, 20 L/h, 120 degrees C) of the crude oil was 1.40-1.70 h. Specific extinctions at 232 and 270 nm were 1.90-2.40 and 0.40-0.62, respectively. Many parameters of S. bigelovii seed oil were quite compatible with those of safflower oil. 相似文献
164.
A four-year crossing scheme involving Spanish V line (V) and Egyptian Baladi Red (B) rabbits was carried out to produce five genetic groups: V, B, 1/2B1/2V(F1), (1/2B1/2V)2(F2), and ((1/2B1/2V)2)2. The last genetic group was considered a new line, named APRI. Body weights (BW) and daily gains in weight (DG) from four to twelve weeks were evaluated for 13,383 rabbits produced by 330 sires and 1074 dams. An animal model was used to estimate heritabilities and common litter effects and a generalized least squares procedure was used to estimate direct additive effects, and direct and maternal heterosis.Heritabilities for growth traits were mostly moderate, ranging from 0.075 to 0.240 for BW and from 0.020 to 0.104 for DG. The V line was heavier and had better gains at each weighing than B rabbits. The F2 and APRI were also lower in most post-weaning growth performance measures than V line rabbits. APRI rabbits were significantly lighter by 39, 26, 46, 64, and 50 g at ages of 4, 6, 8, 10, and 12 weeks, respectively, relative to the purebred V line, while APRI was significantly heavier by 36 and 127 g relative to the B line at 4 and 12 weeks. The V line, in general, had a higher DG than B line. The differences were 3.15, 7.91 and 1.95 g/d at age intervals of 8–10, 10–12 and 4–12 weeks. Differences in direct additive effects between the two lines were in favor of V line rabbits reaching 15.0% (76 g) at 4 weeks and 13.3% (195 g) at 12 weeks. Direct additive effects for DG were significant during most age intervals reaching 35.7% (7.19 g/d) in the interval of 10–12 weeks. All estimates of direct heterosis were positive and ranged from 4.9 to 16.7% for BW and 14.4 to 29.5% for DG, but the estimates for maternal heterosis were, in most cases, significantly negative and ranging from − 4.5 to − 15.2% for BW and from 20.6 to − 36.9% for DG. If the results are confirmed at commercial farms, the APRI line could be reared in heat stress conditions. 相似文献
165.
Concentrations of the halocrbons CCl(3)F (F-11), CCl(2)F(2) (F-12), CCl(4), and CH(3)CCl(3), methane (CH(4)), and nitrous oxide (N(2)O) over the decade between 1975 and 1985 are reported, based on measurements taken every January at the South Pole and in the Pacific Northwest. The concentrations of F-11, F-12, and CH(3)CCl(3) in both hemispheres are now more than twice their concentrations 10 years ago. However, the annual rates of increase of F-11, F-12, and CH(3)CC1(3) are now considerably slower than earlier in the decade, reflecting in part the effects of a ban on their nonessential uses. Continued increases in these trace gas concentrations may warm the earth and deplete the stratospheric ozone layer, which may cause widespread climatic changes and affect global habitability. 相似文献
166.
A cellular microRNA mediates antiviral defense in human cells 总被引:4,自引:0,他引:4
Lecellier CH Dunoyer P Arar K Lehmann-Che J Eyquem S Himber C Saïb A Voinnet O 《Science (New York, N.Y.)》2005,308(5721):557-560
In eukaryotes, 21- to 24-nucleotide-long RNAs engage in sequence-specific interactions that inhibit gene expression by RNA silencing. This process has regulatory roles involving microRNAs and, in plants and insects, it also forms the basis of a defense mechanism directed by small interfering RNAs that derive from replicative or integrated viral genomes. We show that a cellular microRNA effectively restricts the accumulation of the retrovirus primate foamy virus type 1 (PFV-1) in human cells. PFV-1 also encodes a protein, Tas, that suppresses microRNA-directed functions in mammalian cells and displays cross-kingdom antisilencing activities. Therefore, through fortuitous recognition of foreign nucleic acids, cellular microRNAs have direct antiviral effects in addition to their regulatory functions. 相似文献
167.
Distribution of major elements and trace metals as indicators of technosolisation of urban and suburban soils 总被引:2,自引:2,他引:0
Hicham El Khalil Christophe Schwartz Ouafae El Hamiani Jochen Kubiniok Jean Louis Morel Ali Boularbah 《Journal of Soils and Sediments》2013,13(3):519-530
Purpose
Can geochemical characteristics indicate the human impact on soil formation (technosolisation) for urban and suburban soils? This question is assessed for the city of Marrakech located in one of the main agricultural areas of Morocco and characterized by a very rapid rate of expansion. The aim of this work is to assess geochemical properties of surface horizons of urban and suburban soils and to compare them with land use types.Materials and methods
Fifty-eight surface soil samples were collected in different sectors of the city with different land use histories. As land use can be defined as the human use of land, these sampling sites were selected according to the current human activity (e.g., residential districts, agriculture, market-gardening, traditional, or industrial activities) and according to the superposition of the land use over time. All samples were air-dried, disaggregated, homogenized, and then sieved through a 2-mm mesh. Major elements and trace metals were measured in the soil using X-ray fluorescence spectroscopy. For technical limits, Cd was measured using atomic adsorption spectrometry.Results and discussion
Urban and suburban soils of Marrakech present generally similar geochemical compositions for many elements. Siliceous (SiO2) compounds related to the parent material are dominant in these soils. However, the significant concentrations of P2O5 and CaO, measured in some of the urban soils studied, can be attributed to anthropogenic inputs of phosphorus (P) and technic materials, mainly building materials composed of cement and gypsum (plaster). Soils collected from agricultural areas irrigated with urban wastewater and soils developed on rubbish dumps are the most contaminated by metals (e.g., Cu, Zn, and Pb). Therefore, the distribution of major and trace elements in soils underlines the considerable impact of urban land uses.Conclusions
Human activities determine the type of land use, impact the urban environment, and cause a wide spatial diversity of soil quality. The urban and suburban soils of Marrakech contain similar major element distributions except for strongly anthropised soils (soils developed on rubbish dumps and agricultural soils irrigated with urban wastewater). Unlike major elements, trace elements present systematically significantly higher concentrations in urban soils than those measured in control soils. In these conditions, the highest concentrations exceed international clean-up standards and are correlated with land use type. Phosphorus, Ca, and several heavy metals are proposed as indicators of human impacts on soil characteristics in urban and suburban environments. 相似文献168.
Muhammad Akbar Nazir Aslam Tayyaba Khalil Shamim Akhtar Ejaz Hussain Siddiqi Muhammad Sajjad Iqbal 《Journal of plant nutrition》2013,36(17):2080-2091
In the present investigation, different strains of Plant growth-promoting rhizobacteria (PGPR), namely Bacillus megaterium, Pseudomonas fluorescens and Bacillus subtilis were evaluated for their growth-promoting effects on wheat as well as on soil properties under field conditions at two different sites having sandy loam and silt loam type of soils. PGPR strains were evaluated either singly or in consortia. Amongst all the treatments, wheat inoculated with consortia was found most effective as it increased grain yield up to 53% over control in silt loam soil, whereas, corresponding effects in sandy loam soil were less pronounced as an increase of 31% was observed in corresponding treatments, respectively. Enhanced effects on soil properties were also more intense in silt loam as there was an increase of 205% organic matter as against sandy loam soil where this value was 110%. 相似文献
169.
Amal Amin Mohamed Iqtidar Khalil Zeno Varanini Roberto Pinton 《Journal of plant nutrition》2013,36(3):285-295
The role of zinc (Zn) in maintaining the structural and functional integrity of plant membranes was investigated in the present work. The relationship between the activity of NAD(P)H oxidases generating active oxygen species and changes in lipid composition and peroxidation was evaluated in microsomal membrane vesicles isolated from roots of Zn‐defícient bean (Phaseolus vulgaris L., cv. Bobis) plants. Zinc content of bean root microsomal membranes was decreased by about 30% by Zn deficiency. Microsomes isolated from roots of Zn‐deficient plants showed higher rates of NAD(P)H oxidation and NAD(P)H‐dependent O2 ‐ generation than Zn‐sufficient roots. Microsomal O2 ‐ consumption, measured in the presence of pyridine nucleotides, was also considerably enhanced by Zn deficiency. This latter activity was greatly stimulated by Fe(III)EDTA, while inhibited by Superoxide dismutase (SOD) and catalase, indicating that active oxygen species were produced during the oxygen consuming enzyme reaction. Zinc deficiency caused a decline in microsomal phospholipid (PL) content. In addition, saturated fatty acids were present at a higher proportion than unsaturated fatty acids in microsomes from Zn‐deficient roots. Sterol content of microsomal vesicles was also modified by Zn deficiency, which led to an increase in the planar sterol campesterol and a concomitant decrease in stigmasterol and sitosterol content. NADPH‐dependent lipid peroxidation, directly measured in microsomal vesicles as malondialdehyde (MDA) production, was slightly enhanced by Zn deficiency. These results support the idea that Zn deficiency determines an enhanced generation of harmful oxygen species by membrane‐associated enzymes and show that this activity can be more pronounced in the presence of iron (Fe), which accumulates in Zn‐deficient tissues. The relationship between the occurrence of this phenomenon and the changes in membrane lipid profile is discussed. 相似文献
170.
Liming Chen Khalil Tubail David Kost Warren A. Dick 《Journal of plant nutrition》2013,36(7):1040-1055
Gypsum (CaSO4·2H2O) addition during composting of manure or biosolids can reduce ammonia nitrogen losses and represents a new method for controlling odors. Additional work is needed, however, to test the ability of the gypsum-containing composts to support plant growth and affect uptake of nutrients and heavy metals. A field study using broccoli (Brassica oleracea L. var. italica) and a growth chamber study using tall fescue (Festuca arundinacea) were conducted by application of composts at 10 Mg ha?1 for broccoli and 10 and 25 Mg ha?1 for tall fescue. Compared to composts without gypsum, at 10 Mg ha?1, gypsum composts significantly increased or had a strong trend to increase yields of broccoli and tall fescue. Gypsum composts affected concentrations of nutrient elements but did not increase concentrations of environmental concern elements in broccoli flowers and tall fescue tissue. Thus gypsum composts can be safely applied to soils to enhance crop growth. 相似文献