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61.
62.
The essential oil, chloroform extract and seven sesquiterpenoids compounds newly isolated from the oleo-gum-resin of Commiphora mukul showed a wide range of inhibiting activity against both Gram (+) and Gram (-) bacteria. 相似文献
63.
64.
A study was conducted to investigate the effects of cow manure and sewage sludge application on the activity and kinetics
of soil l-glutaminase. Soil samples were collected from a farm experiment in which 0, 25, and 100 Mg ha−1 of either cow manure or sewage sludge had been applied annually for 4 consecutive years to a clay loam soil (Typic Haplargid).
A chemical fertilizer treatment had also been applied. Results indicated that the effects of chemical fertilizer and the solid
waste application on pH in the 18 surface soil (0–15 cm) samples were not significant. The organic C content, however, was
affected significantly by the different treatments, being the greatest in soils treated with 100 Mg ha−1 cow manure, and the least in the control treatment. l-Glutaminase activity was generally greater in solid-waste applied soils and was significantly correlated (r = 0.939, P < 0.001) with organic C content of soils. The values of l-glutaminase maximum velocity (Vmax) ranged from 331 to 1,389 mg NH4
+–N kg−1 2 h−1. Values of the Michaelis constant (K
m) ranged from 35.1 to 71.7 mM. Organic C content of the soils were significantly correlated with V
max (r = 0.919, P < 0.001) and K
m (r = 0.763, P < 0.001) values. These results demonstrate the considerable influence that solid waste application has on this enzymatic
reaction involved in N mineralization in soil. 相似文献
65.
Nazifi S Ansari-Lari M Asadi-Fardaqi J Rezaei M 《Veterinary journal (London, England : 1997)》2009,182(2):315-319
Acute phase proteins (APPs) such as serum amyloid A (SAA), haptoglobin (Hp), and plasma fibrinogen (Fb) are diagnostic and prognostic biomarkers. This study determined the pattern of SAA in traumatic reticuloperitonitis (TRP) in cows, and compared the findings with Hp, and plasma Fb concentrations in the differential diagnosis of TRP using receiver operating characteristic (ROC) analysis. Blood samples were collected from 89 cows: 53 cases of TRP, 16 animals with other internal disorders and 20 healthy controls.SAA and Hp had a similar pattern and magnitude of changes in TRP. Using the ROC method, the optimal cut-off for the diagnosis of TRP was 68 μg/mL for SAA and 0.74 g/L for Hp, with 100% sensitivity and 86.1% specificity; either of these parameters may therefore be used as a sensitive and relatively specific tool for the differential diagnosis of TRP in cattle. The diagnostic accuracy of plasma Fb was significantly lower than either SAA or Hp (P < 0.01). The combined use of these APPs (whilst aware of their conditional interdependence) may not provide any additional diagnostic information than can be obtained using either SAA or Hp alone. 相似文献
66.
ABSTRACT The interactive effects of concomitant infection by the nematode Pratylenchus penetrans and the fungus Verticillium dahliae on symptom expression in Russet Burbank potato was studied in growth chamber experiments. Treatments were P. penetrans at three initial densities, V. dahliae at one inoculum density, the combination of the nematode at these three densities and the fungus, and a noninfested control. Gas exchange was measured nondestructively in leaf cohorts of different ages, one to three times weekly, with a LI-COR portable photosynthesis system. The single-pathogen treatments had no effect on assimilation or transpiration rates, but joint infection had a significant impact. In concomitant infection, photosynthesis was impaired more than transpiration, so estimates of leaf health were based on carbon assimilation rates only. Reductions in assimilation rate were apparent before the onset of visual symptoms. Assimilation rates decreased as much as 44% in the top, and newest, leaves of concomitantly infected plants, compared to rates in control plants. Even so, the health of newly produced leaves did not become progressively worse through time. With light use efficiency less than 0.20 mol of CO(2) fixed per mol of photosynthetically active radiation used as the criterion for disease incidence, disease progressed acropetally from the oldest to the youngest leaves. In plants infected with P. penetrans (0.8 nematodes per cm(3) of soil) in combination with V. dahliae, all leaves in cohorts 1 and 2 were symptomatic by 45 days after planting, and leaves in cohorts 3 to 6 became symptomatic at weekly intervals thereafter. For the control and single-pathogen treatments, the first time that light use efficiency fell below 0.20 in all leaves in cohort 1 was 71 days after planting. Concomitant infection reduced leaf life span by about 3 weeks. Both visual and physiological symptom expression were invariant to differences in initial nematode inoculum densities ranging from 0.8 to 2.5 nematodes per cm(3) of soil in one experiment and from 1.3 to 4.1 nematodes per cm(3) of soil in a second experiment. 相似文献
67.
Summary Sheep are partially susceptible toSchistosoma mansoni infection. However, development of worms is slow and they are reduced in size. No anaemia is produced in the infected animals,
but a moderate degree of eosinophilia occurs at a late stage. The peculiar pathological lesions observed in the liver of ruminants
is recorded and a simple technique suitable for perfusion of adult schistosome worms in large animals is described.
Sumario Los ovinos son parcialmente susceptibles a la infección conSchistosoma mansoni. Sin embargo, el desarrollo de los parásitos es lento y tambien estan reducidos en tama?o. No se produce anemia en los animales infectados pero si ocurre un grado moderado de eosinofilia en los estadíos finales. Las lesiones patológicas peculiares observadas en el hígado de los rumiantes son descritas y tambien una tecnica simple adecuada para la perfusión de schistosomas adultos en animales mayores.
Résumé Les moutons sont fablement sensibles à l'infection àSchistosoma mansoni. Toutefois, le développement des vers est lent et ceux-ci ont une taille réduite. Les animaux infectés ne présentent pas d'anémie, mais une éosinophilie modérée se produit à un stade avancé. Les lésions pathologiques spécifiques observées dans le foie des ruminants sont décrites, ainsi qu'une technique simple de perfusion de schistosomes adultes chez les grands animaux.相似文献
68.
Wang Yang Li Shuangyi Xu Yingde Li Ming Shan Te Zhang Weijun Liu Xu Saeed Muhammad Farhan Wang Jingkuan 《Journal of Soils and Sediments》2020,20(11):3941-3950
Journal of Soils and Sediments - The distribution and dynamic of residue-derived carbon after incorporation into soil at different fertility levels have been well documented. However, the... 相似文献
69.
Muhammad Nafees Muhammad Jafar Jaskani Saeed Ahmad Muhammad Shahid Zaffar Malik Moazzam Jamil 《The Journal of Horticultural Science and Biotechnology》2017,92(2):199-205
The present study was conducted to screen out elite pomegranates through determination of biochemical diversity in wild and cultivated genotypes for a breeding program and for fresh/processed use in industry. The results showed high morphological diversity in accessions of wild pomegranate fruits as compared to cultivated genotypes. The first six principal components covered 80.75 and 75.49% diversity in 53 wild and 62 cultivated pomegranate genotypes, respectively. High values of the coefficient of variance (10.78–18.62%), and a high range of minimum to maximum values of total soluble solids, titratable acidity, ascorbic acid content, total soluble sugars, and total phenolic content (0.10–1.25, 5.88–29.96, 9.69–19.85 and 175.05–595.42), respectively, were recorded in the studied genotypes. Ascorbic acid content had a strong correlation with antioxidant activity (0.952%), super dismutase oxides (0.94%), catalase (0.921%), and titratable acidity (0.91%). Peroxides had a strong correlation (0.88%) with catalase, and 0.81% each with super dismutase oxides and antioxidant activity. Wild and cultivated pomegranates were clustered successfully in separate groups, based on biochemical traits. A variety improvement program and selection of high-quality pomegranate genotypes could help to reduce pomegranate-related malnutrition issues in the human diet. 相似文献
70.
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