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1.
Three thermophilic bacteria strains, designated strain BS1, BS2 and BS3, resistant to β-lactam antibiotics, and leaving at an optimal temperature for growth of about 50°C, were isolated from traditional baths in Meknes-city in Morocco. Physiological and biochemical studies showed that these organisms belong to Gram positive Bacilli. They could not be identified with the Bergey's Manuel of Systematic Bacteriology (1986). The dosage of β-lactamase during the exponential growth phase has revealed that the strain BS3 produces a maximal amount of this enzyme. Studies aimed at determining the optimal conditions for incubation and growth have been performed in order to optimize the excretion of β-lactamase by BS3 cells and thus facilitate the purification and and characterization of this enzyme.  相似文献   
2.
A 45-day experiment was carried out to evaluate the growth performance,digestive enzymes activity and biochemical response of Cirrhinus mrigala fed graded levels of oil.Three isonitrogenous purified diets(6%,8%and 10%of oil)were formulated.A total of 108 juveniles of Cirrhinus mrigala(5.95±0.25)g were equally distributed in triplicate groups in nine plastic tanks of 100 L capacity and fed under natural light cycle.Growth performance of the fish significantly reflected the effect of inclusion levels of oil tested but the diet with 8%lipid had the best significant growth performance[%weight gain,Feed Conversion Ratio(FCR)and Specific Growth Rate(SGR)],across different experimental groups.Levels of secretion of digestive enzymes in the fish fed different experimental diets resulted in significant values of(p0.05)amylase and lipase,while Aspartate transaminase(AST),Alanine transaminase(ALT),Lactate dehydrogenase(LDH)and Malate dehydrogenase(MDH)values in the muscle and liver decreased significantly(p0.05)as the levels of oil in the diet increased.However,serum biochemical parameters did not record any significant difference(p0.05)with the exception of the total lipid across diets.The study confirmed the inclusion effect of graded levels of oil in juvenile Mrigal diet,but the inclusion should not be more than 8%to avert growth depression.  相似文献   
3.
Background: Feline ureteral obstructions have emerged as a common problem. Ureteral strictures rarely are reported as a cause and the predisposing factors and clinical course of this condition have not been described. Objectives: Evaluate cases of feline ureteral strictures and characterize historical features, clinical signs, diagnostic imaging, surgical and endoscopic findings, histopathology, treatment modalities, and short‐ and long‐term outcomes. Animals: Ten cats diagnosed with ureteral strictures based on compatible findings from at least 2 of the following: ultrasonography, ureteropyelography, surgical exploration, or histopathology. Methods: Retrospective study. Results: Median age, serum creatinine concentration, and size of the renal pelvis were 12 years, 3.7 mg/dL, and 11.75 mm, respectively. Six of 10 cats had hyperechoic periureteral tissue on ultrasound examination at the stricture site. Four cats had evidence of a circumcaval ureter at surgery. Eight cats had an intervention including ureteral stent placement (n = 6) and traditional surgery (n = 2). Seven of 8 cats had decreases in serum creatinine concentration and renal pelvic parameters preceding discharge and 6 had persistently improved results at their last examination. All patients survived to discharge. Median survival time was >294 days (range, 14 to >858 days) with 6/10 cats still alive. Conclusions and Clinical Importance: Ureteral strictures may occur in cats secondary to ureteral surgery, inflammation, a circumcaval ureter, impacted ureterolithiasis, or for unknown causes. With appropriate and timely intervention, the prognosis for long‐term survival is good. In addition to ureteral reimplantation or ureteronephrectomy, ureteral stenting or SC ureteral bypass may be considered as future therapeutic options.  相似文献   
4.
The alkaloidic fraction of the methanol extract of Peganum harmala seeds was tested in vitro on three tumoral cell-lines: UCP-Med and Med-mek carcinoma, and UCP-Med sarcoma. Proliferation was significantly reduced at all tested concentrations (20-120 micrograms/ml) during the first 24 h of contact. A cell lysis effect occurred after 24 h and increased thereafter to complete cell death within 48-72 h, depending on tested concentration.  相似文献   
5.
Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time.  相似文献   
6.
The present study was undertaken to evaluate the effects of feeding the male mice with miso that was prepared with a mixture of microbial starters on the level of lipid peroxidation as a marker of oxidative stress, antioxidant power of hepatocytes, the enzymatic and non-enzymatic antioxidant. The starters that were used in the preparation of miso were Aspergillus oryzae and Pleurotus ostreaus or A. oryzae and Bacillus subtilis. The miso that was prepared with A. oryzae and Bacillus subtilis has more effect on suppressing the oxidative stress and enhancement of endogenous antioxidant of hepatocytes and renal tissue of mice.  相似文献   
7.
The historic Sanborn Field located on University of Missouri campus at Columbia, Missouri, was designed to demonstrate the importance of agricultural practices, such as fertilization, tillage, and crop rotation. Knowledge of the effect of long-term agricultural practices on the soil quality is critical for farmers to make better management decisions to efficiently and sustainably produce crops. This study examined long-term fertilization, tillage, and crop rotation effects on the activities of soil enzymes including phenol oxidase, peroxidase, dehydrogenase, cellulose, and β-glucosaminidase in the top soil layer (0–10 cm). The results showed that pH, organic matter, and cation exchange capacity are important factors that are associated with enzyme activities. Compared to conventional tillage, no-tillage treatment significantly increased activities of phenol oxidase, peroxidase, dehydrogenase, and d β-glucosaminidase. Fertilization increased cellulase and β-glucosaminidase activity, but had mixed effects for phenol oxidase, peroxidase, and dehydrogenase depending on the type of fertilizer applied. The amount of nitrogen applied significantly affected soil enzyme activities. The influences of the crop type and rotation are significant but differ for each enzyme. Due to the sensitivity of soil enzymes to environmental factors, soil enzymes such as phenol oxidase, dehydrogenase, cellulose, and β-glucosaminidase are suitable as indicators of soil quality.  相似文献   
8.
The Abbassa selection line (developed by selective breeding) and the Kafr El Sheikh commercial strain (widely used in Egypt), both Oreochromis niloticus, were compared at two stocking densities (two and four fish m?2). Harvest weight, length, depth, width and head length were recorded. The Abbassa line showed a superior harvest weight (28 per cent) over the Kafr El Sheikh strain. Males were heavier than females, but the between‐sex difference was greater in the commercial than in the Abbassa line (39 and 31 per cent respectively). Females in the Abbassa line grew almost as fast as males in the commercial line. Both strains grew faster at the lower density, and the percentage reduction in harvest weight at the higher density was about the same for both strains (27 per cent). The advantage of the Abbassa line was 28 per cent at both densities. Both strains had a similar survival rate (approximately 80 per cent) during the grow‐out period. We conclude that the Abbassa line is ready for release to the tilapia industry in Egypt. Further evidence is being sought in currently underway on‐farm evaluations. Measures should be taken to ensure the long‐term viability of the Abbassa line.  相似文献   
9.
Wheat grain yield and protein content are significantly influenced by the onset of senescence and the duration of the grain filling phase. The onset of senescence also affects Nitrogen use efficiency (NUE) through interacting pathways involving N accumulation and translocation of N into the grains. The objective of this study was to relate variation in NUE and its components with two groups of the NAM-A1 gene alleles; (i) early onset of senescence in cultivars carrying the NAM-A1a allele, (ii) delayed onset of senescence in cultivars carrying the Non-NAM-A1a allele (b, c, d) in wheat cultivars grown under Western Australia conditions. A field trial was carried out over two seasons examining 19 cultivars under different N rates and time of N application. The Normalized Difference Vegetation Index was utilized to determine the onset of senescence after anthesis. The early onset of senescence results in high grain yield, harvest index, and NUE due to improvements in the N utilization ability. Accelerating the onset of senescence results in a short grain filling period leading to grain maturity before the onset of unfavourable summer conditions. The function of alleles of NAM-A1 gene in controlling senescence hence the NUE is highly regulated by environmental conditions. This study concluded that the function of NAM-A1a allele induces the onset of senescence with a positive effect on the NUE and its components under Western Australian conditions.  相似文献   
10.
<正>Dear Editor,Accurate measurement of volumetric soil water content (θ_v) is essential for efficient soil water management. HydraSCOUT (HS) probes are capacitance-type probes for θ_v measurement with high accuracy, but require calibration for different soil types. We aimed to  相似文献   
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