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1.
The aim of this study was a comparison of key haematological features of diploid (2n) and triploid (3n) Caspian salmon (Salmo trutta caspius). Morphometric indices of erythrocytes were determined on blood smears by light microscopy. Triploidy significantly (P < 0.001) increased all morphometric indices measured in the erythrocytes including cell size, cell surface area, and cell volume. The increase in cell size was larger for the major (27%) axis than for the minor (22%) axis, thus making erythrocytes of 3n Caspian salmon more ellipsoidal. The estimated increase in erythrocyte nuclear volume (87%) was bigger than the theoretical expected 50% increase. Haematological indices were measured manually by hemocytometry. Triploids had lower numbers of red blood cells (RBC: 1,120,000 cells/mL in 2n vs. 700,000 cells/mL in 3n; P < 0.001) but they were larger in size (mean erythrocytic volume [MEV]: 363.1 nm3 in 2n vs. 483.3 nm3 in 3n; P < 0.001). The decrease in RBC number was not compensated by the increase in MEV and, thus, triploidy affected the haematocrit (Hct: 38.8% in 2n vs. 33.06% in 3n; P < 0.05). Total blood hemoglobin concentration was lower in triploid fish (Hb: 9.9 g/dL in 2n vs. 8.9 g/dL in 3n; P < 0.05). In contrast, mean erythrocytic hemoglobin (MEH: 95 μg in 2n vs. 133.2 μg in 3n; P < 0.001) was higher for 3n Caspian salmon as a result of their larger erythrocytes, although MEH concentration (MEHC: 0.26 g/dL in 2n vs. 0.27 g/dL in 3n) did not significantly differ (P > 0.05). White blood cell (WBC) counts (lymphocytes and neutrophiles) were measured and WBC/RBC ratios were calculated. There were no significant differences in WBC (15,710 cells/mL in 2n vs. 12,683 cells/mL in 3n; P > 0.05), lymphocytes, and neutrophils as %WBC as well as WBC/RBC ratios between two ploidy levels (P > 0.05). Triploid Caspian salmon showed higher erythrocyte abnormalities such as ‘twisted’, ‘tailed’, and ‘anucleated’ cells as well as high portions of immature RBC in blood smears in comparison with diploids (P < 0.001).  相似文献   
2.
Background: Bone tissue engineering requires materials that are biocompatible, mechanically suited for bone function, integrated with the host skeleton, and support osteoinduction of the implanted cells for new bone formation. The aim of this study was to compare the osteogenic potential of xenograft with hydroxyapatite/β- tricalcium phosphate (HA/β-TCP) scaffold. Methods: New Zealand rabbits (n = 9) were divided into 3 groups. Osteoblast cells were originally isolated from rabbit iliac crest and cultured in DMEM/F12. After creating a critical-sized defect (2 × 3 cm) in rabbit tibia bone, the defect was filled with an implant of HA/TCP with osteoblasts and xenograft in the hole of left (as control) and right tibia, respectively. The new bone formation and the development of bone union within the defect were evaluated by x-ray images and eosine and hematoxylin staining at 4, 8, and 12 weeks post-operation. Results: The bone partially formed in both groups was filled with osteoblast cultured on porous implants at 4 weeks. Over time, progressive bone regeneration was observed inside the pores. Moreover, a progressive vascular ingrowth and progressive integration with the host bone were obvious in xenograft when compared to HA/β-TCP. A good integration between the xenograft implants and the bone was observed radiographically and confirmed by histological section. Conclusion: The result showed that the bone defect can be repaired using both synthetic and xenograft implants. However, the xenograft showed a better osteointegration as compared to HA/β-TCP scaffold.Key Words: Osteoblasts, Hydroxyapatite/β-Tricalcium phosphate (TCP), Bone tissue  相似文献   
3.
This study was carried out to evaluate milt quality in male Caspian brown trout (Salmo trutta caspius) over the course of the winter spawning season. Milt samples were collected biweekly during December and January. Chemical composition of seminal fluid, sperm production (milt volume, sperm density, spermatocrit,) and sperm motility characteristics (percentage and duration of motility) were measured. Milt volume, sperm density, osmolality, seminal minerals (Ca2+, Mg2+, K+, Na+, Cl?), and total protein gradually decreased over the spawning season. Glucose and triglyceride content of milt did not show significant changes over the spawning season. Milt pH and the percentage and duration of motility were comparatively stable, declining only at the end of the season. Significant positive correlations were found between sperm density and seminal minerals, total protein and spermatocrit; percentage of motile spermatozoa and seminal minerals, total protein; and duration of motility and K+, Cl?, total protein, and pH. Results show that season has a significant influence on milt quality in male Caspian brown trout, with the best milt being available at the beginning of spawning season.  相似文献   
4.
Forty landraces of Damask rose were collected from 28 provinces (13 origin sites) in Iran and evaluated to determine the diversity among them. The investigated characters were: flower weight, flower diameter, peduncle length, number of petals, number of stamens and oil content. Pearson's coefficients showed that number of petals was positively correlated with flower weight (r = 0.642) and number of stamens (r = 0.630), while its correlation with peduncle length was negative (r = −0.53). A negative correlation was obtained between oil content and number of stamens (r = −0.60) which is useful for indirect selection of landraces with low number of stamens and therefore high amount of oil content. Cluster analysis based on five botanical characters and oil content separated the origin site 12, which included Guilan, Mazandaran and Golestan provinces with a specific climate condition of temperate humid, from other origin sites. This distinctiveness was already confirmed by the bi-plot of the principal components. The distribution of Damask rose landraces provided useful information for the future collection and for the genetic resource management in these origin sites.  相似文献   
5.
Lavandula stoechas L. plant is a perennial evergreen used as a fragrant ornamental and medicinal plant. In order to study the effect of foliar spray of zinc sulfate (ZnSO4) (0, 1000, and 2000 mgL?1) and sodium chloride (NaCl) salinity (0, 75, and 150 mM) on some physiological characteristics of Lavandula stoechas L. plants, a pot experiment was carried out at the Research Greenhouse of Azarbaijan Shahid Madani University, Iran. Physiological characteristics [root and leaf dry weights, total soluble solids (TSSs), total anthocyanins, chlorophyll b, Zn2+, potassium (K+) contents, and K+/Na+ ratio] were significantly affected by the interaction effects of ZnSO4 foliar application and salinity levels. The highest root dry weight, chlorophyll b, anthocyanin, and Zn contents as well as TSS were found in the plants with NaCl0 × ZnSO4 2000 mgL?1. For Na+, the greatest value was recorded with NaCl 150 × ZnSO40. The highest K+/Na+ ratio was found in the control plants. Foliar application of ZnSO4 promoted the total phenolic content, especially at 2000 mgL–1. The highest amounts of flower dry weights were recorded at NaCl0. Chlorophyll a, total flavonoids, stem dry weight, and essential oil content were affected with ZnSO4 treatment and salinity levels. The highest values for the essential oil content, chlorophyll a content, and stem dry weight were attained by the nonsaline treatment. Both foliar application levels positively influenced the essential oil and flavonoid contents of the plants. The results reveal that zinc application had marked effects on the physiological characteristics of Lavandula stoechas L. plants growing under salinity stress conditions.  相似文献   
6.
To induce synchronized ovulation, migrating wild Caspian brown trout (Salmo trutta caspius) females were treated with two interperitoneal injections of Des‐Gly10, d ‐Ala6 LHRH (LHRHa), given 3 days apart. Two injections of 100 μg kg?1 body weight of this hormone effectively induced ovulation. Within 27 days from the second injection, all fish injected with 100 μg kg?1 LHRHa had ovulated compared with 54.5% of the controls. The mean time to ovulation was reduced significantly (P<0.05) from 31.67±4.84 days in control fish and 28.83±7.31 days in sham‐treated fish to 16.36±1.61 days in fish injected with 100 μg kg?1 LHRHa. The fertilization rate in 50 and 100 μg kg?1 LHRHa‐injected fish was significantly lower than that in the control fish (P<0.05). In fish injected with 50 and 100 μg kg?1 LHRHa, significant (P<0.05) changes in testosterone (T) and 17α‐hydroxyprogestrone (OHP) levels were observed. After the second LHRHa injection, the fish injected with 100 μg kg?1 showed the highest serum levels of testosterone and OHP. These results demonstrate that the use of LHRHa can effectively reduce the mean time to ovulation and induce synchronized ovulation in Caspian brown trout.  相似文献   
7.
Phytophthora root rot caused by Phytophthora drechsleri Tucker is one of the most devastating sugar beet diseases in tropical areas. To identify genetic resources resistant to this disease, an aggressive isolate of P. drechsleri was selected. Then, a screening method was optimized based on the standard scoring scales of 1–9 (1: no symptoms, 9: complete plant death). Finally, 19 sugar beet lines, three cultivars, and 14 accessions of the wild species Beta vulgaris subsp. maritima, B. macrocarpa, B. procumbens, and B. webbiana were evaluated for resistance to the most aggressive isolate of P. drechsleri by using the optimized method (inoculum included 20 g of rice seed together with superficial wound creation). The isolates of P. drechsleri had significant variation in aggressiveness, and Kv10 was the most aggressive isolate on the susceptible variety Rasoul. The lines O.T.201-15, SP85303-0 (resistant check), and S2-24.P.107 had the lowest disease index with scores of 3.09, 3.13, and 3.27 respectively; they were categorized into the resistant group. The interaction between isolates and genotypes was not significant, which indicated the same response of each genotype to different isolates. Investigating the resistance of different generations of sugar beet revealed that progeny selection would be an effective method for increasing the resistance level of breeding materials to P. drechsleri. Among the wild species, the accession 9402 belonging to B. macrocarpa and the accession 7234 of B. vulgaris subsp. maritima had the lowest disease index (2.29 and 2.60, respectively) and were categorized into the resistant group.  相似文献   
8.
The yield of sugar beet depends mainly on the effective protection to a number of pests and diseases affecting the crop. In the absence of actual methods of management, as in the case of viral diseases, the availability of genetic resistance sometimes allows the survival of the crop in the affected areas. Integration of molecular markers in conventional breeding procedures has provided a reliable means for improving the efficiency of selection methods. The present review summarizes the evolution, thanks to the application of molecular techniques, of traditional breeding for resistance to some biotic stresses in sub-arid environments.  相似文献   
9.
The effects of moisture content (8%, 10%and 12%), variety (Tarom and Fajr) and parboiling on milling quality of rice as a function of milling recovery (MR), head rice yield (HRY), degree of milling (DOM) and whiteness were investigated. The parboiled grains was prepared with three soaking temperatures of 25 oC, 50 oC and 75 oC and three steaming times of 10, 15 and 20 min. As a result of parboiling, the increasing rates of MR and HRY values were 7.8%and 14.3%for Tarom and 9.8%and 10.0%for Fajr, respectively, and the decreasing rates for DOM and whiteness were 6.6%and 10.8%for Tarom and 6.8% and 10.5% for Fajr, respectively. Moreover, decreasing moisture content to 8%maximized MR (75.8% for Tarom and 74.3% for Fajr) and HRY (65.8% for Tarom and 57.0% for Fajr) while increasing that to 12%revealed maximum values of DOM (6.1%for Tarom and 6.2%for Fajr) and whiteness (24.8%for Tarom and 28.2%for Fajr).  相似文献   
10.
This study was undertaken to study the effect of Satureja khuzestanica essential oil (SKEO) in male rat fertility. SKEO was administered orally at doses of 75, 150, and 225 mg/kg/day for 45 days through drinking water. Treated and control rats were mated with female on day 45 of treatment. SKEO significantly improved all the parameters evaluated such as potency, fecundity, fertility index, and litter size. Moreover, concentrations of FSH and testosterone were significantly increased in SKEO-treated groups. Also the weights of testes, seminal vesicles, and ventral prostate weights were increased by SKEO (225 mg/kg). Histopathological analysis showed that in male rats treated with SKEO (150, 225 mg/kg) the number of spermatogonium, spermatid cords, Leydig cells, and spermatozoids was increased. Also in these groups, the Sertoli cells were hypertrophic.  相似文献   
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