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991.
Internal bond (IB) strength is one of the most important me-chanical properties that indicate particleboard quality. The aim of this study was to find a simple regression model that considers the most ... 相似文献
992.
993.
Agrobacterium tumefaciens‐mediated transformation (ATMT) is being increasingly recognized as an effective insertional mutagenesis tool in studies of filamentous fungi for gene discovery and functional analysis. We developed and optimized ATMT for 2 Colletotrichum species, Colletotrichum gloeosporioides and Colletotrichum acutatum, the causative agents of Colletotrichum leaf disease in rubber trees in Southern China. A. tumefaciens strain AGL‐1 carrying an ILV1 gene and a green fluorescent protein gene were used to transform the conidia of these 2 Colletotrichum species. The transformation efficiency was correlated with the co‐cultivation duration and bacterial cell concentrations, which reached 300–400 transformants per 1 × 106 conidia after optimization. Southern blot analysis indicated that about 60.0% of the C. gloeosporioides transformants and 46.2% of the C. acutatum transformants had a single copy of T‐DNA in their genomes. Fungal genomic DNA segments flanking the T‐DNA were identified in the transformants through thermal asymmetrical interlaced polymerase chain reaction followed by sequencing. The flanking sequences from 4 C. acutatum and 7 C. gloeosporioides transformants showed moderate or weak homology to the NCBI database entries. Some sequences matching those reported virulence‐related genes. The results suggest that the T‐DNA inserted mutants banks constructed are useful for the discovery of new or important genes and to elucidate their function in the 2 Colletotrichum species. 相似文献
994.
In our investigation to find out new anti-acne agent, we focused on Terminalia laxiflora Engl & Diels (Combretaceae) methanolic wood extract, which has been selected during previous screening experiments for anti-acne agents, which included 29 species of Sudanese medicinal plants. Based on the biologically guided fractionation using an antibacterial assay against Propionibacterium acnes, a lipase inhibitory assay and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay; five tannin-related compounds were isolated, such as ellagic acid, flavogallonic acid dilactone, terchebulin and gallic acid. Terchebulin showed good antibacterial activity; minimum inhibitory concentration (MIC) = 125 μg/ml and minimum bactericidal concentration (MBC) = 250 μg/ml. Gallic acid exhibited lipase inhibitory activity with IC50 value of 149.3 μM, which showed strong inhibition compared with terchebulin, IC50 260.7 μM. However, all compounds exhibited better or equal DPPH radical scavenging activity to (+)-catechin as positive control. Ellagic acid and terchebulin showed the best DPPH radical scavenging activities, IC50 4.86 and 4.90 μM, respectively. This study demonstrated that terchebulin has potentiality as an anti-acne agent. 相似文献
995.
Najmeh Shirvani-Farsani Abbas Ali Zamani Saeed Abbasi Katayoon Kheradmand 《Journal of pest science》2013,86(3):591-597
Lycoriella auripila (Winnertz) (Diptera: Sciaridae) is one of the most frequently seen pests of cultivated mushrooms, Agaricus bisporus (Lange) Imbach. The effects of different concentrations of diazinon, imidacloprid and deltamethrin, and tobacco extract were tested against L. auripila on varieties 737 and A15 of button mushroom. Also, economic injury level (EIL) of fungus gnat was evaluated on variety 737. Different varieties of button mushroom were cultured and weight of harvested mushrooms was recorded to provide an estimate of yield loss. A linear regression analysis was used to determine the relationship between pest density and mushroom yield. Imidacloprid was the most effective insecticide against L. auripila on both varieties and caused 100 % control at the highest tested concentration. The lowest concentration of diazinon (500 ppm a.i.) increased pest emergence on 737 and A15. This is possibly due to the hormoligosis. Deltamethrin and tobacco extract were ineffective against fungus gnat between both varieties. High levels of adults of L. auripila were associated with significant reduction in mushroom yield. EIL were calculated according to the number of L. auripila required to cause the critical yield loss from the predictive model and by control costs, mushroom price, and the reduction of injury due to spraying by imidacloprid and diazinon. The lowest values of EIL were related to imidacloprid compared with diazinon. This is due to the different efficiency of these two insecticides, for it causes mortality in population of L. auripila. Based on this research, for the first time clear EILs are introduced to the button mushroom growers for treatment of L. auripila. 相似文献
996.
J. HEWSON R. JOHNSON L. G. ARROYO A. DIAZ‐MENDEZ J. A. RUIZ‐LÓPEZ Y. GU J. R. E. Del CASTILLO 《Journal of veterinary pharmacology and therapeutics》2013,36(1):68-77
Hewson, J., Johnson, R., Arroyo, L. G., Diaz‐Mendez, A., Ruiz‐López, J. A., Gu, Y., del Castillo, J. R. E. Comparison of continuous infusion with intermittent bolus administration of cefotaxime on blood and cavity fluid drug concentrations in neonatal foals. J. vet. Pharmacol. Therap. 36 , 68–77. Healthy neonatal foals were treated with cefotaxime by bolus (40 mg/kg IV q6h for 12 doses; n = 10) or by infusion (loading dose of 40 mg/kg IV followed by continuous infusion of a total daily dose of 160 mg/kg per 24 h for 3 days; n = 5). Population pharmacokinetics was determined, and concentrations in cavity fluids were measured at steady state (72 h). Highest measured serum drug concentration in the bolus group was 88.09 μg/mL and minimum drug concentration (Cmin) was 0.78 μg/mL at 6‐h postadministration (immediately before each next dose), whereas infusion resulted in a steady‐state concentration of 16.10 μg/mL in the infusion group. Mean cefotaxime concentration in joint fluid at 72 h was higher (P = 0.051) in the infusion group (5.02 μg/mL) compared to the bolus group (0.78 μg/mL). Drug concentration in CSF at 72 h was not different between groups (P = 0.243) and was substantially lower than serum concentrations in either group. Insufficient data on pulmonary epithelial lining fluid were available to compare the methods of administration for cefotaxime in this cavity fluid. Results support continuous drug infusion over bolus dosing in the treatment for neonatal foal septicemia to optimize time that cefotaxime concentration exceeds the minimum inhibitory concentration of common equine pathogens. 相似文献
997.
N. Villarino S. Lesman A. Fielder D. García‐Tapia S. Cox M. Lucas J. Robinson S. A. Brown T. Martín‐Jiménez 《Journal of veterinary pharmacology and therapeutics》2013,36(4):329-339
The objective of the study was to assess the pharmacokinetics of tulathromycin in lung tissue homogenate (LT) and plasma from healthy and lipopolysaccharide (LPS)‐challenged pigs. Clinically healthy pigs were allocated to two dosing groups of 36 animals each (group 1 and 2). All animals were treated with tulathromycin (2.5 mg/kg). Animals in group 2 were also challenged intratracheally with LPS from Escherichia coli (LPS‐Ec) 3 h prior to tulathromycin administration. Blood and LT samples were collected from all animals during 17‐day post‐tulathromycin administration. For LT, one sample from the middle (ML) and caudal lobes (CL) was taken. The concentration of tulathromycin was significantly lower in the ML after the intratracheal administration of LPS‐E. coli (P < 0.02). In healthy pigs and LPS‐challenged animals, the distribution of the drug into the lungs was rapid and persisted at high levels for 17‐day postadministration. The distribution of the drug within the lung seems to be homogenous, at least between the middle and caudal lobes within dosing groups. The concentration versus time profile of the drug and pharmacokinetic parameters in two different lung areas (middle and caudal lobe) were consistent within the groups. The clinical significance of these findings is unknown. 相似文献
998.
Hadi Atashi Jamshid Izadifard Mohammad Javad Zamiri Amir Akhlaghi 《Tropical animal health and production》2013,45(4):1051-1054
In the present study, 1,635 lambing records of Ghezel (n?=?766) and Mehraban (n?=?869) breeds were used to evaluate the early growth traits, litter size, and lamb survival in sheep reared in Fars Province, southern Iran, during a 5-year-long period. The least squares means (± SE) of lamb birth weight for Ghezel were 5.27 (±0.22), 5.02 (±0.22), and 3.98 (±0.23) kg for single males, single females, and twin lambs, respectively; whereas, the corresponding values for Mehraban were 4.39 (±0.18), 4.18 (±0.18), and 3.50 (±0.19) kg. The least squares means of pre-weaning lamb growth (gram per day) for Ghezel were 239 (±15), 218 (±15), and 181 (±16) for single males, single females, and twin lambs, respectively, and the corresponding values for Mehraban were 204 (±12), 187 (±12), and 156 (±13). Lambs from 2 year old ewes or younger were on average lighter at birth and at weaning and had a lower average daily gain than those from older ewes (P?<?0.05). The percentage of twin births increased from 1.1 and 1.3 % for ewes aged ≤ 2 years to 19 and 12 % for those aged ≥ 6 years old in Ghezel and Mehraban, respectively (P?<?0.05). The mean pre-weaning lamb mortality was 7.1 and 4.1 % for Ghezel and Mehraban, respectively. 相似文献
999.
1000.
Nahid Y. El Sayed Ekhlas M. Abdelbari O. M. Mahmoud S. E. I. Adam 《The Veterinary quarterly》2013,33(2):80-85
Ten Nubian goats were given oral doses of the fresh fruits and leaves of Cassia senna at 1, 5, and 10 g / kg /day. Eight goats died within 30 days and two others were slaughtered in a moribund condition on days 18 and 29. The clinical signs of diarrhoea, inappetence, loss of condition, and dyspnoea were well correlated with the pathological findings. There was an increase in G.O.T., ammonia, urea, and total cholesterol and a decrease in total protein in the serum of Cassia‐poisoned goats. Blood sugar level was reduced and the increase in the values of Hb, PCV, and RBC was due to haemoconcentration. 相似文献