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171.
Dr. Moustafa S. Saleh 《Journal of pest science》1987,60(3):55-57
Two bacterial insecticides,Bacillus thuringiensis H-14 andB. sphaericus 1593 were evaluated for larvicidal potency against mosquito larvae ofAedes aegypti. LC50 values showed thatB.thuringiensis H-14 (4×105 spores/ml) had a higher pathogenicity against fourth larval instars ofA. aegypti thanB. sphaericus (3.1×106 spores/ml) by about 7.75 times. Larval selection with LC90 of both pathogens for 8 successive generations caused a decrease in the susceptibility levels of selected strains ofA. aegypti as compared with the original strain. Moreover, the results indicated that the effect of larval selection with the above bioinsecticides led to an obvious reduction in the egg production and hatchability of eggs produced by mosquito adults that developed from surviving larvae. 相似文献
172.
Antioxidant capacity, antioxidant compounds and antioxidant enzyme activities in dates of five cultivars during development and ripening were studied in the 2009 and 2010 seasons. Fruit growth followed a smooth sigmoid curve with maximum weight at the bisir stage. Both the antioxidant capacity measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the antioxidant compound (phenols, tannins and vitamin C) concentrations decreased from young stages through to the maturation and the ripening stages. The antioxidant capacity was highly positively correlated with the concentration of antioxidant compounds in most cultivars. The activities of the antioxidant enzymes, peroxidase, catalase and polyphenoloxidase (PPO) increased from the hababouk through to the kimri and/or the bisir stage, upon cultivar, and thereafter, declined at the ripening stages. The possible relation of these biochemical changes with fruit maturation and ripening was discussed. 相似文献
173.
Hassan Mokhtarpour Christopher Teh Ghizan Saleh Ahmad Selamat Mohammad Esmail Asadi Behnam Kamkar 《Archives of Agronomy and Soil Science》2013,59(8):853-871
Corn (Zea mays L.) is planted in two seasons per year in northern Iran (mid-April as a main crop and mid-June as a second crop). The main objective of this study was to determine whether corn yield response would differ between these two seasons and different plant populations. Two field experiments were conducted at the Agricultural Research Center of Golestan – Iran in 2007 and 2008 at different planting densities. The results showed that the values of grain yield and most traits were significantly lower in the second season. Maximum grain yield was observed at planting densities of 6.5 plants m?2 in the first season, whereas in the second season grain yield was the same for planting densities between 2.5 and 12.5 plants m?2. Based on the second-year experimental results, the following functions were fitted to show the relationship between yield ha?1 (Y) and planting densities (X) for the first and second seasons, respectively: (Y = ?167.6X 2 + 2672.2X + 511.77; R 2 = 0.992) and (Y = 1200.1 ln(X) + 2924.4; R 2 = 0.935). This study found that the optimum plant population was 6.5 plants m?2 under low heat stress, and should be reduced to 2.5–4.5 plants m?2 under heat stress conditions. 相似文献
174.
Livia Lucentini Antonella Palomba Hovirag Lancioni Lilia Gigliarelli Mauro Natali Fausto Panara 《Fisheries Research》2006,80(2-3):251-262
Northern pike (Esox lucius) is not considered an endangered species in Italy, but since recent studies indicate the decline of this population, conservation and management strategies based on the genetic differentiation of natural northern pike populations are needed. In this paper, genetic diversity was analysed in 10 Italian and 2 East European northern pike populations by means of seven microsatellite loci. Data indicated an appreciable genetic differentiation, in spite of a low genetic variation, and agreed with the low level of genetic polymorphism already observed for this species in North America and North Europe. Results of statistical tests revealed genetic peculiarities of the Italian populations, even though signals of recent contact between populations were found and discussed in relation to anthropic impacts, particularly to the stocking practice. This investigation represents the first approach to the knowledge of the genetic variability of Italian pike populations using microsatellite markers, and reported results could be of interest for future management and conservation programmes of this species in Italy. 相似文献
175.
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177.
Jaime Viscasillas Livia Benigni David Brodbelt Hatim Alibhai 《Veterinary anaesthesia and analgesia》2013,40(6):e83-e90
ObjectiveTo determine if the use of needle enhancing software facilitate injection technique in ultrasound‐guided peripheral nerve blocks.Study designProspective, blinded, randomized controlled trial.AnimalsEight hind limbs from canine cadavers.MethodsThe limbs were randomly allocated to two groups; software on (group I) and software off (group II). Eight anaesthetists with no previous experience of ultrasound‐guided regional anaesthesia were recruited. Thirty‐six procedures were carried out (18 per group). After sciatic nerve visualisation via ultrasonography, the anaesthetist introduced a needle guided by ultrasonography. When the tip of the needle was considered by the anaesthetist to be as close as possible to the nerve without touching it, 0.05 mL of methylene blue dye was injected. Parameters evaluated included: number of attempts to visualise the needle with ultrasonography, time spent to perform the technique, subjective evaluation of ease of needle visualisation, proximity of the tip of the needle to the nerve, and, at dissection of the leg, inoculation site of the dye in relation to the nerve.ResultsSignificant differences between groups were identified in relation to the number of attempts (group I: median 1, IQR: 1 – 1 attempts versus group II: median 1, IQR: 1 – 4 attempts, p = 0.019), and the relationship between the dye and the nerve during hind limb dissection (72.2% of the nerves were stained in group I versus 16.6% in group II,p = 0.003). No significant difference between groups was observed with respect to the time taken to perform the procedure (group I: median 25.5, IQR: 18.4 – 44.3 seconds versus group II: median 35.7, IQR: 18.6–78.72 seconds, p = 0.31), subjective evaluation of the needle visualization (p = 0.45) or distance between the tip of the needle and the nerve as measured from the ultrasound screen (p = 0.23).Conclusions and clinical relevanceThis study identified greater success rate in nerve staining when the needle enhancing software was used. The results suggest that the use of this technique could improve injection technique amongst inexperienced anaesthetists performing ultrasound‐guided peripheral nerve blocks in dogs. 相似文献
178.
Ten Egyptian and imported entomopathogenic nematodes were evaluated for their pathogenicity to R. ferrugineus in both the laboratory and the field. In the laboratory, most nematodes were pathogenic to the pest larvae, pupae and adults. Larvae and adults were more susceptible to nematode infection (mostly 100% mortality) than pupae enclosed in their cocoons. In the field however, the highest insect larval mortality was 66.67% and most of nematodes failed in controlling the pest. Such failure could be due to hot weather, the tunnelling behaviour of the pest larvae and the too much sap in the infested sites in the trunks of palm trees. 相似文献
179.
Surface ultrastructural observation of the thyroid gland in donkey revealed the coexistence of certain unusual follicles or cysts, the ultimobranchial (UB) follicles, which exhibited large diameters and less regular outlines. In addition, several small follicles, cell nests or solid cellular masses were also demonstrated in association with these structures. Surface of most UB follicular cells was almost hexagonal in shape, studded with sparse or dense pleomorphic microvilli, which were much denser at the cellular borders. Each follicular cell bore single cilium that projecting over the cell surface. Interestingly, bleb-like apocrine protrusion of the apical cytoplasm of some follicular cells was frequently demonstrated. These apocrine blebs (or aposomes) were varied in shape, size and showed smooth or irregular surface. In addition to such aposomes, deep to shallow circumscribed or eroded areas of the apical cell surface was frequently demonstrated. These findings indicate that the UB follicular cells in donkeys, similar to those of camels, exhibit an apocrine activity alongside with the usual merocrine mode of secretion. 相似文献
180.
In this study, 73 cows with different types of traumatic reticuloperitonitis (TRP) and sequellae along with 25 healthy buffalo cows were used to evaluate the total blood serum protein and protein electrophoresis. According to rumenotomy or necropsy findings, the affected buffalo cows were classified into acute local TRP (AL-TRP), chronic local TRP (CL-TRP), reticular abscess (RA), acute diffuse TRP (AD-TRP), purulent pericarditis (PPC) and fibrinous pericarditis (FPC). Polyclonal gammopathy was characteristic for the electrophoretogram of buffalo cows with CL-TRP (55%), RA (61.1%) and PPC (62.5%). Various degrees of hypoalbuminaemia, hyper-alpha-globulinaemia and low A/G ratios were the associated changes in all cases of TRP and sequellae. Hyper-beta-globulinaemia was noticed in cases with CL-TRP, RA and PPC. Hyper-gamma-globulinaemia was evident in cases with AL-TRP, CL-TRP, RA and PPC. Hyperproteinaemia was noticed in buffalo cows with local complications of TRP including AL-TRP, CL-TRP and RA. Hypoproteinaemia associated with severe hypoalbuminaemia (>50% reduction compared to controls) and very low A/G ratios (<0.4) characterized buffalo cows with AD-TRP, PPC or FPC. In conclusion, the concentrations and electrophoretic patterns of serum proteins in buffaloes differ according to the anatomical location of the foreign body and the associated pathological lesions. 相似文献