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1.
Journal of Crop Science and Biotechnology - Drought is a major limiting factor of wheat production globally. In this research, salicylic acid was used in order to increase drought tolerance in...  相似文献   
2.
Western blots of proteins of 14 Mycoplasma iowae strains and isolates resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were probed with three monoclonal antibodies (MAbs), MI6, MI7, and MI8. MAb MI6 reacted with one or more antigens with apparent molecular weights of 60,000, 70,000, and 94,000. In three strains (N-PHN-D13, R-D2497, and K 1805), antigens located on a single peptide band were recognized, while in others additional epitopes at different molecular-weight positions were revealed. A similar pattern was observed with MAb MI7, although it reacted with fewer antigens than did MAb MI6 and failed to recognize antigens in strains N-PHN-D13 and R-D2497. MAb MI8 reacted with an antigen at an apparent molecular-weight position of 28,000 in four of the 14 strains and isolates. The diverse reaction patterns observed with the MAbs in the 14 M. iowae strains and isolates confirms the occurrence of antigenic variation within this species. Antigenic variation in M. iowae may be pivotal in determining host-parasite interactions, pathogenesis, and the outcome of disease.  相似文献   
3.
Brazilian red propolis was administered orally to Santa Inês ewes, and evaluation was made of general health and hematological, biochemical, and parasitic responses during and after flushing. Thirty mature, nonlactating, nonpregnant Santa Inês ewes (40?±?2 kg and 2.5 years old) were grazing tropical pasture (Brachiaria decumbens and Pennisetum purpureum) and, as flushing after synchronization, were supplemented with a concentrate–roughage mixture at a rate of 4 % body weight (BW). Ewes were divided according to BW and fecal egg count (FEC) into two groups (n?=?15 each): control and propolis that received propolis ethanolic extract at rates of, respectively, 0 and 3 g/ewe/day. The treatments lasted 21 days until the end of flushing period. BW and body condition score (BCS) were recorded, and blood and fecal samples were taken weekly for 8 weeks. Mean values of BW and BCS were not (P?>?0.05) affected by propolis administration. Propolis increased (P?<?0.01) total leukocytes (WBC), but no significant differences were observed for other hematological parameters. Propolis increased (P?<?0.01) total protein and globulin concentrations and decreased (P?<?0.01) triglycerides, glutamate oxaloacetate transaminase, and glutamate pyruvate transaminase. Propolis decreased (P?<?0.05) FEC. Propolis administration had good impact on ewe health and may be a promising feed additive during critical periods such as flushing.  相似文献   
4.
A panel of monoclonal antibodies (MAb) developed against Mycoplasma gallisepticum strain PG31 was used to probe the antigenic profiles of 5 recognized strains (PG31, R, S6, F, A5969) and 6 field isolates of M gallisepticum. Monoclonal antibody G9 predominantly recognized antigens at apparent molecular mass positions of 90 to 98 kDA. The MAb reacted with all strains and isolates, but the molecular mass position of the antigens varied among some mycoplasmas. Monoclonal antibody G12 reacted with all strains and isolates of M gallisepticum and had an identical banding pattern. However, MAb G10 and G11 reacted selectively only with a limited number of strains and/or isolates. Surface distribution of the MAb-recognized antigens was revealed by immunoelectron microscopy. Partial physicochemical characterization of MAb G9-recognized antigens identified glycopeptide characteristics. Monoclonal antibody G9 reacted with surface antigens and, hence, participated in agglutination of M gallisepticum. However, the degree of agglutination varied among the various strains and isolates, indicating a quantitative or conformational limitation or an alteration in the anomeric expression of the epitopes. Antigenic variation in M gallisepticum may be mediated by immunologic selective pressures, or a proclivity for habit niche in the host.  相似文献   
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6.
Constructed wetlands have been recognized as offering a removal treatment option for high concentrations removal of chemical and biological contaminants in domestic wastewater. The enteric protozoan parasite Cryptosporidium is considered one of the highly resistant to treatment and highly infectious organisms to humans and animals. Moreover, some species of Cryptosporidium are known to have a zoonotic nature. In this investigation a pilot scale for domestic wastewater treatment system was used, consisting of the following steps in series: (1) up-flow anaerobic sludge blanket (UASB) reactor, (2) free water surface (FWS) wetland unit, and (3) sub-surface flow (SSF) wetland unit. This treatment system was fed with domestic wastewater to assess its efficiency in removing Cryptosporidium oocysts. The obtained Cryptosporidium oocysts were detected and enumerated by two different staining techniques ‘acid fast trichrome (AFT) and modified Ziehl Neelsen (MZN) stains’. Polymerase chain reaction (PCR) technique was also used to detect Cryptosporidium DNA in wastewater samples. Results revealed that anaerobic treatment (using UASB reactor) could remove about 53.1% of Cryptosporidium oocysts present in raw wastewater. The in-series connection between the two wetland units allowed complete elimination of Cryptosporidium oocysts as the first (FWS) wetland unit removed 95.9% of the oocysts present in anaerobically treated wastewater and the remaining portion of oocysts was completely removed by the second (SSF) wetland unit. Cryptosporidium oocysts were detected in 95.8% of raw wastewater samples with a mean count of 43.8 oocysts/l when AFT stain was used while they were detected in only 87.5% of raw wastewater samples with a mean count of 35.6 oocysts/l when MZN stain was used. Polymerase chain reaction (PCR) technique was able to detect Cryptosporidium DNA in only 45.8% of raw wastewater samples. Positive PCR results were only achieved in wastewater samples containing 52 oocysts or more per liter.  相似文献   
7.
The antifeedants triphenyltin acetate and hydroxide and neem seed kernel extracts in two concentrations each, were evaluated as control measures against the sorghum shoot fly,Atherigonu varia soccata Rond. in comparison with the insecticides presently used for this purpose. The antifeedants appeared to be partially effective and were less active than the insecticides.  相似文献   
8.
Leaf extracts ofVitex negundo L,Synadenium grantii Hook. f. andProsopis juliflora (SW) DC, and cake ofAzadirachta indica A. Juss. were evaluated for their efficacy in reducing the population of the green leafhopper,Nephotettix virescens (Distant), and its transmission of rice tungro virus under field conditions. All four plant species tested reduced the population of the vector significantly in both the nursery and main field. The lowest population of the vector was recorded with application of neem cake at 5 kg/0.032 ha of nursery, followed by foliar spray of neem seed kernel extract at 5% in the main field. Rice tungro disease incidence was also less in this treatment, with maximum grain yield of 3580 kg/ha in ‘Kharif’ (July-Oct.) and 3257 kg/ha in ‘Rabi’ (Nov.-March) seasons, and a cost:benefit ratio of 1:3.9 in both seasons. However, the maximum cost:benefit ratio of 1:5.6 and 1:5.8 in Kharif and Rabi seasons, respectively, was recorded withV. negundo.  相似文献   
9.
One hundred and twenty eight, 28‐weeks‐old Lohmann LSL hybrid layers were used in this experiment, which lasted 12 weeks to investigate the effect of propolis supplementation on the productive performance, egg quality traits and haematological variables of laying hens. All hens were randomly classified into four equal experimental groups, eight replicates (4 birds/each). Hens in group 1 were fed on a commercial diet and considered as control group, while those in groups 2, 3 and 4 were fed on the same commercial diet and supplemented with 250, 500 and 1000 mg propolis/kg diet. The obtained results revealed that daily feed consumption/hen increased insignificantly with increasing propolis level than that of the control group. Regarding the means of egg mass and egg production rate, it was observed that the laying hens fed diets containing 250 and 1000 mg propolis/kg significantly (p < 0.05) produced more and heaver egg in comparison with control group. External egg quality traits have not affected with increasing the level of propolis, while eggshell weight was significantly (p < 0.05) increased. The internal egg quality traits except albumen and yolk percentages increased significantly (p < 0.05) with increasing propolis level for treated hens as compared to those in the control. Concerning the haematological parameters, the results showed that the levels of total protein and globulin increased significantly with increasing propolis level, while cholesterol and liver enzymes were significantly decreased (p < 0.05). Heterophils count of hens in the treated groups significantly decreased, whereas the lymphocyte count significantly increased, resulting in a decreased H/L ratio than that of the control group. Thus, it could be concluded that the supplementation of 250 mg propolis/kg diet is highly recommended to improving egg production, blood constituent and haematological parameters of the commercial laying hens.  相似文献   
10.
Three categories of tobacco products were studied using electron paramagnetic resonance (EPR) spectroscopy: Cuban cigar brand name Montecristo, four international trademark cigarettes, and three types of Middle Eastern tobacco blends called Al-Moassal or Jurak. The Montecristo Cuban cigar is used as standard of high-quality tobacco. Mainly two EPR signals from all of the studied samples are observed: a very weak sharp EPR signal superimposed on a broad signal. The broad EPR signal is attributed to a manganese(II) complex. The intensity of the manganese(II) EPR signal is found to be related to the quality of the tobacco content. The sharp signal, which is characteristic of semiquinone radicals, is observed at room temperature, and its intensity increases drastically with temperature.  相似文献   
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