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81.
The aim of this study was to evaluate the intracellular activity of two types of liposome-encapsulated enrofloxacin (LE) compared with free enrofloxacin and non-treated control against Staphylococcus aureus, phagocytosed by monocytes in healthy Anatolian Shepherd dogs. Enrofloxacin was encapsulated with two different types of liposome in multilamellar large vesicles (MLV). Type A MLV were composed of 15 mg phosphatidylcholine and 35 mg cholesterol, Type B MLV were composed of phosphatidylcholine, cholesterol and enrofloxacin in a molar ratio of 1:1:1. Intracellular activity was estimated by comparing the numbers of bacteria surviving intracellularly in monocytes exposed to free enrofloxacin and LE for 4 h at the doses of 0.25, 0.5 and 1 microg/ml, with those surviving intracellularly in untreated control monocytes. All three forms of enrofloxacin (free, Type A and B liposomes) increased the intracellular killing of S. aureus in a concentration dependent manner. Comparison of 1 microg/ml Type B LE revealed that killing activity was significantly higher than those of other concentrations. The results showed that LE was superior in reducing the number of intracellularly located bacteria compared to the free drug and control. The beneficial effect of liposomal encapsulation is presumably due to the fact that both liposomes and bacteria are localized at the same spot in phagocytic cells.  相似文献   
82.
ABSTRACT The genetic structure of field populations of begomoviruses and their whitefly vector Bemisia tabaci in Pakistan was analyzed. Begomoviruses and B. tabaci populations were sampled from different crops and weeds in different locations in Punjab and Sindh provinces, in areas where cotton leaf curl disease (CLCuD) occurs or does not occur. Phylogenetic analysis based on nucleotide sequences of the intergenic region in the viral DNA-A provided evidence of two clusters of isolates: viruses isolated from species in the family Malvaceae, and viruses isolated from other dicotyledon families. Analysis of the capsid protein (CP) open reading frame grouped isolates into three geographical clusters, corresponding to isolates collected in Punjab, Sindh, or both provinces. Random amplified polymorphic DNA analyses of the B. tabaci population showed that intrapopulation diversity was high at both the local and regional scales. Sequence analysis of the mitocondrial cytochrome oxydase I (mt COI) gene showed that the B. tabaci population was structured into at least three genetic lineages corresponding to the previously described Indian, Southeast Asian, and Mediterranean-African clades. The Indian clade was present only in Punjab, the Mediterranean-African only in Sindh, and the Southeast Asian in both provinces. B. tabaci haplotypes of the Indian clade were found only in the Punjab, where CLCuD occurs. Hence, the geographical distribution of virus and vector genotypes may be correlated, because similar phylogenetic relationships were detected for the viral CP and the vector mt COI genes.  相似文献   
83.
A serological survey was carried out to assess the occurrence of anti-Neospora caninum antibodies in dogs from the State of Pernambuco. A total of 625 serum samples of dogs (289 from Paulista, 168 from Amaraji and 168 from Garanhuns) were tested by an immunofluorescence antibody assay for the detection of anti-N. caninum antibodies. A total of 177 (28.3%; IC 95%, 24.9-32.1) samples were positive. The seropositivity rates found in Paulista, Amaraji and Garanhuns were 26% (IC 95%, 21-31.4), 26.2% (IC 95%, 19.7-33.5) and 34.5% (IC 95%, 27.4-42.2), respectively. Of the 177 serum samples positive to anti-N. caninum antibodies, 170 were additionally tested for the presence of anti-Toxoplasma gondii antibodies and out of these 57.6% (IC 95%, 49.8-65.2) were positive. The results indicate that dogs from Amaraji, Paulista and Garanhuns are exposed to both N. caninum and T. gondii infections. The presence of dogs infected by N. caninum in Pernambuco represents a potential risk factor for the occurrence of outbreaks of abortion in cattle and small ruminants in this state. This study is the largest serological survey on the presence of anti-N. caninum antibodies in dogs carried out in Brazil and reports for the first time the exposure to N. caninum and T. gondii in dogs from Pernambuco.  相似文献   
84.
A case of protothecosis is reported in an adult goat with inspiratory dyspnea and stertor. Dermatitis with prominent ulcerated nodules up to 3 cm in diameter was observed in the muzzle at the mucocutaneous junctions of nasal and lip skin, and in the border of the pinna. Histologic lesions were necrotizing pyogranulomatous dermatitis and rhinitis with myriads of walled sporangia, characteristic of Prototheca wickerhamii. This seems to be the first report of protothecosis in a goat.  相似文献   
85.
Two experiments were carried out to evaluate the effects of palm kernel meal (Elaeis guineensis) as corn (Zea mays) substitutes in tambaqui (Colossoma macropomum) diets based on zootechnical performance, health, characteristics of the muscle, yield and economic efficiency. The first one was carried out in a recirculation aquaculture system for 75 days wherein tambaquis received diets with 0% (T0), 25% (T25), 50% (T50), 75% (T75) and 100% (T100) of corn replacement by palm kernel meal. The second experiment, conducted in ponds for 184 days, tambaquis were fed T0 and T25 diets (selected because showed greater weight gain without health damage). Final weight and weight gain of tambaquis were impaired by the increasing levels of this ingredient on diets, and the feed conversion ratio was worse. The protein efficiency ratio and specific growth rate gradually reduced, while the total number of leucocytes and neutrophils gradually increased. Cholesterol and triglycerides decreased in T75 and T100. Variables analysed in experiment 2 were not affected by treatment, except muscle lipids. Palm kernel meal can replace up to 25% of corn in tambaqui diets since it maintains a balance in economic and zootechnical performance of production.  相似文献   
86.
Kim  Kim  Sohn  Sim  Park  Heo  Lee  Lee  Jun  Jang 《Journal of fish diseases》1998,21(1):11-17
The causative viral agent was purified from diseased shrimp Penaeus japonicus with white spot syndrome (WSBV). Several hundred clones were obtained from libraries of the purified viral genomic DNA. According to the results of nucleotide sequence analysis, none of the WSBV clones showed considerable sequence homology with those of other known viruses, indicating that WSBV is a new virus causing a serious disease in shrimp. Based on the sequence data of WSBV genomic DNA, a pair of polymerase chain reaction (PCR) primers was designed. After 30 cycles of PCR amplification of viral genomic DNA extracted from WSBV, a single product of the expected size was detected. Southern blot hybridization confirmed that the amplified product was specific to the DNA of WSBV. The PCR system was able to detect 1 pg of WSBV DNA after 30 cycles, and efficiently amplify the target region of WSBV gene in the total nucleic acids extracted either from the diseased shrimp or hatchery shrimp with no signs of viral infection.  相似文献   
87.
The objective of the present paper was to obtain haematological and biochemical parameters of calves during their milk feeding. Another goal was to compare a current feed ration containing the commercial feed mixture Biosan with two alternative rations comprising skimmed milk and fat supplement. The effect of milk drink acidification and the effect of the physical form of fat added to skimmed milk were investigated. the calves were divided into six groups, by 6 to 8 calves each (P1-Biosan, PP1-acid variant, P2-skimmed milk+fat concentrate powder KMKS, PP2-acid variant, P3-skimmed milk+fat paste, PP3-acid variant). The highest average daily liveweight gains were recorded in calves fed on unacidified skimmed milk with fat paste supplement (1.074 kg)-Tab. I. The highest average daily liveweight gains were observed in calves fed on fat paste enriched milk drink (P3) while the calves administered milk with fat concentrate powder (P2) had only slightly higher average daily weight gains than the calves on Biosan diet (group P1). The growth of daily weight gains as a result of diets containing acidified milk (PP1 and PP2) is also a positive finding; this growth is even statistically significant in the former case (P < 0.05). The calves showed hypohaemoglobinaemia from the beginning of the experiment (51.3-69.0 g/l) and the low haematocrit value (0.29-0.43 l/l), Tab. II, while the plasma iron level was paradoxically high (Tab. V).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
Equilibrium sorption of n-alkyl esters (dimethyl suberate, diethyl suberate, diethyl sebacate, dibutyl suberate and dibutyl sebacate) and monodisperse alcohol ethoxylates (diethylene glycol, tetraethylene glycol, pentaethylene glycol, hexaethylene glycol and octaethylene glycol monododecyl ether) between the reconstituted cuticular waxes of Stephanotis floribunda Brongn (Madagascar jasmine) or Hordeum vulgare L (barley) leaves and an external aqueous receptor solution was determined. Logarithms of the wax/receptor partition coefficient (K(wax/rec)) of the n-alkyl esters increased linearly with the number of C-atoms. With alcohol ethoxylates, log K(wax/rec) decreased linearly with the number of ethylene oxide units. For both groups of compounds, K(wax/rec) increased with increasing lipophilicity. The values of K(wax/rec) in Stephanotis wax were between 5 and 16 times higher than in barley wax. It is argued that this difference was due to different chemical composition and crystallinity of the waxes. Mobility of [14C]2,4-dichlorophenoxybutyric acid (2,4-DB) in reconstituted Stephanotis and barley wax was increased by a factor of 2-8 by both n-alkyl esters and alcohol ethoxylates. Effects on the mobility of 2,4-DB were linearly related to the internal concentrations of n-alkyl esters and alcohol ethoxylates in reconstituted Stephanotis or barley wax. At the same internal concentrations the effect of n-alkyl esters on the mobility of 2,4-DB in wax exceeded that of alcohol ethoxylates by between 1 and 2 orders of magnitude. Results are discussed in relation to formulating systemic pesticides.  相似文献   
89.
The rumen inocula taken from cows and sheep were incubated in pH controlled anaerobic batch cultures and the effect of the elevated redox potential (Eh) on metabolism of glucose was examined. In Eh regulated cultures (Eh = +100 mV) the VFA production and production of methane were decreased with a concomitant increase of production of lactate. In these cultures counts of lactilytic bacteria tended to be lower and counts of lactic acid bacteria higher than in cultures with a normal Eh. The elevated Eh also exerted an inhibitory effect on the rumen protozoa. The relevance of these changes to the rumen metabolism is discussed.  相似文献   
90.
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