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101.
102.
For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L−1 and 500 mg·L−1 and combinational treatment of scarification with gibberellic acid of 250 mg·L−1 and 500 mg·L−1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.  相似文献   
103.
The city of Tehran,like many polluted metropolises of the world,has higher emissions of greenhouse gases than other cities in Iran,due to heavy consumption of fossil fuel and landuse changes.To estimate carbon sequestration in two 40 year-old stands of planted Cupressus arizonica and Fraxinus rotundifolia in degraded lands surrounding Tehran,sampling of above-and below-ground biomass,soil(at two depths of 0-15 and 15-30 cm),and leaf litter was done by systematic random sampling.The total carbon stocks of C.arizonica and F.rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1.The aboveground biomass with 233.16(71%)Mg·ha-1 in C.arizonica and88.16(58.50%)Mg·ha-1 in F.rotundifolia contributed the most shares to carbon sequestration.The diameter at breast height,total height,basal area,total volume,and biomass of C.arizonica were significantly(p0.01)higher than those of F.rotundifolia.Also the depth of 0-30 cm of soil contributed between 18.29%and 32.15%of total ecosystem carbon,respectively.The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars,respectively.Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land,the current status quo.These stands can absorb atmospheric CO2 at different rates,thus tree species selection and stand development should be considered in planning future afforestation projects.  相似文献   
104.
This study is designated to assess the effect of the severity of Babesia ovis infection on sialic acid concentration in blood sera in naturally infected sheep. Infected animals (diseased group) comprised 38 Iranian fat-tailed sheep, about 1–3 years old, naturally infected with B. ovis, divided into four subgroups with respect to parasitemia rates (low 0.1–0.3 %, moderate 0.4–0.9 %, high 1–2.5 %, and very high >2.5 %). The parasitological diagnosis was confirmed using PCR analysis. As a control group, ten clinically healthy sheep reared under the same management and environmental conditions were also sampled. Hematological parameters and the concentrations of total sialic acid (TSA), lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured in both groups. Compared to controls, sialic acid concentrations showed significant increase (p?Parasitemia rate was positively correlated with sialic acid concentrations. This study demonstrated that B. ovis infection induced marked and persistent elevations of serum sialic acid concentrations. It seems that increase of serum sialic acid concentrations during parasitemia alter receptor-ligand interactions, which are known to play important role in immune response. Furthermore, sialic acid would indirectly inhibit the action of leukocytes and consequently promote the evasion of the immune response and persistence of the parasite in the host. This factor could influence the parasite-host cell adhesion, but further detailed biochemical investigations are needed to precisely explain the exact role of sialic acid in invasion process of the parasite to the host cells.  相似文献   
105.
The objective of the present study was to investigate the morphometrical features of the cat cerebellum using design-based stereology. Cerebellar hemispheres from four male cats were examined. Isotropic, uniform random sections were obtained and processed for light microscopy. Cerebellar total volume (V), white (WM) and grey matter (GM) volume fractions, and the volumes of the molecular and granular layers were measured using the Cavalieri's estimator and the point counting system. Cerebellar surface area was estimated using test lines, and Purkinje cellular and nuclear volumes were analysed using the nucleator technique. The volume of the cat cerebellar hemispheres was 2.06 ± 0.29 cm3. The relative volume fractions of the GM and WM were 70.6 ± 2.6% and 29.3 ± 2.6%, respectively. The surface area of the cerebellar hemisphere was 68.2 ± 17.8 cm2. The volumes of the molecular and granular layers were estimated at 0.89 ± 0.16 cm3 and 0.56 ± 0.1 cm3, respectively. The Purkinje cell volumes were found to be ranging from 1,717 to 28,489 µm3, of which cells with a perikaryon volume of 6,994 µm3 had a higher incidence. The Purkinje nuclear volume was estimated at 440–3,561 µm3, and nuclei with a volume of 1,252 µm3 were the most frequently occurring ones. Our data might contribute to the veterinary comparative neuroanatomy knowledge, help develop experimental studies in this field, and possibly lead to advancement in the diagnosis and treatment of nervous diseases in the cat.  相似文献   
106.
Bread staling involves a combination of physico-chemical phenomena that leads to a reduction of quality. This study aims at evaluating the impact of baking conditions (280 °C, 8 min; 310 °C, 5.5 min; 340 °C, 4 min), baking type (of fully baked (FB) and part-baked (PB)) and storage temperature (−18, 4 and 20 °C) on the staling of Sangak bread. Results showed that lower baking temperature with longer baking time produced drier bread with higher firmness. In FB Sangak breads, amylopectin retrogradation, amount of unfreezable water and firmness (measured by compression test) increased during storage at positive temperatures but hardness (determined by Kramer shear test) decreased significantly during first day of storage. The recrystallized amylopectin traps the free water resulting in crumb hardening. Water is also absorbed by the dry crust resulting in changes of rheological properties in the crust and crumb, and finally in staling. Storage at 4 °C resulted in increasing melting enthalpy of amylopectin crystallite in comparison with storage at 20 °C. Also it was found that firmness of PB breads due to rebaking was significantly lower than FB breads. There were no significant changes in staling parameters of FB and PB stored at −18 °C.  相似文献   
107.
An experiment with factorial arrangement of treatments on a randomized complete block (RCB) design basis with three replications was conducted in a greenhouse during Spring 2010 to investigate changes in sodium ion (Na+), potassium ion (K+), Na+/K+ and to determine proline, protein content, and superoxide dismutase (SOD) of four wheat and four barley cultivars. Three salt levels {1, control (no salt), 7, and 13 dS m?1 [2.5 and 5 g salt [sodium chloride (NaCl) and sodium sulfate (Na2SO4) in 1:1 ratio] per kg of soil, respectively]} were used in this investigation. Salt stress treatments were applied 4 weeks after planting (at 2 leaf stage). Leaf samples were taken four weeks after imposition of salt treatment. The results showed that salinity caused an increased in proline and protein content, and SOD in all wheat and barley cultivars. The highest proline and protein content of barley and wheat cultivars at all salinity levels were observed in ‘Nimrooz’ and ‘Bam’ cultivars, respectively. At all salinity levels, wheat and barley cultivars ‘Kavir’ and ‘Nimrooz’, respectively, had the lowest Na+ content. Barley cultivar ‘Kavir’ and wheat cultivar ‘Bam’ had higher K+ and K+:Na+ ratios. This might be related to salt tolerance in these two cultivars. Wheat and barley cultivars showed differences with regard to proline, protein, and SOD content, Na+, K+, and K+:Na+ ratio, indicating existence of genetic diversity among the cultivars. These findings indicated that higher K+, K+:Na+ ratio, proline, protein, and SOD content could be the key factors, which offer advantage to barley over wheat for superior performance under saline conditions.  相似文献   
108.
Topography is the most factor that has the greatest impact of all factor that affect the distribution.To study the diversity of trees and shrub species in the Perc forest situated in Khorramabad,Lorestan,140 circular plots of 1200 m~2 in a grid of 300 m 9 250 m were surveyed,using a systematic random sampling method.In each plot,the Margalef richness index,Shannon–Wiener diversity index,Hill's N_1 and Simpson indices and the evenness index of Simpson and Smith-Wilson were calculated and ordered on the basis of different classes of elevation,exposition and slope.The results indicated that slope did not have any significant effect on the indices.Exposition and elevation classes significant impacted the richness and diversity indices,but did not influence evenness.In general,the highest plant diversity was observed for slopes less than 15 %,northern aspects,without geographical direction,and elevations of 2100–2200 m.This information can be very useful in achieving the goals for sustainable management of forests.In addition to greater protection for regions with high diversity and reforestation(compatible species) in degraded area,we can help increase diversity in forests.  相似文献   
109.
To investigate the seed protein and major mineral nutrient (Fe, Zn, P, and N) contents and their accumulation procedure in the seeds of common bean (Phaseolus vulgaris L.), a biennial experiment was conducted under two contrasting moisture regimes (normal irrigation and water deficit). Seed reserves of eight genotypes (WA4502-1, WA4531-17, Akhtar, D81083, AND1007, KS21486, MCD4011, and COS16) were investigated at four stages of seed filling period (SFP). Split-plot experiments were performed as randomized complete block design with four replications. The results showed significant differences in the evaluated characteristics in both factors, the genotypes and the moisture regimes. Fe content of the seeds was affected the most by drought stress and reduced in all stages, while seed nitrogen and protein contents were affected the least under stress condition. The percentages of reductions due to water deficit were higher in stage 1 for Fe, stage 2 for Zn, and stage 4 for P and N. In the stage 3, minerals had the least changes. Nitrogen content of the seeds at mid-stages of SFP increased slightly under drought stress. Drought stress also caused 39–69% reductions in the grain yield of the genotypes. Under drought stress condition, the concentrations of Fe and N in the white bean seeds were less than that of the red and the Chitti genotypes. However, the seed P contents of the white bean seeds were higher than that of the other genotypes.  相似文献   
110.
Anti-Müllerian hormone (AMH), produced by granulosa cells, has been reported to be elevated in mares with granulosa cell tumor. A 13-year-old Arabian mare was referred after 3 years of infertility. Rectal and ultrasonographic examination revealed enlargement and multicystic appearance of the left ovary. The mare had substantially higher concentration of AMH (21.6 ng/mL) compared with normal cyclic mares (n = 5; 0.36 ± 0.02 ng/mL). Testosterone (50 pg/mL) concentration was also elevated, but progesterone concentration (0.4 ng/mL) was lowered. Accordingly, the mare was presumptively diagnosed with granulosa-theca cell tumor and a left ovariectomy implemented using ventral midline approach under general anesthesia. Histopathological examination confirmed the diagnosis of granulosa-theca cell tumor. Serum concentrations of AMH decreased to 2 ng/mL and 0.5 ng/mL 2 and 4 weeks after tumor removal, respectively. In conclusion, the current report presents confirmatory evidence that evaluation of serum AMH could be useful for diagnosis of granulosa cell tumor in mare.  相似文献   
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