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41.
The structure of foot-and-mouth disease virus has been solved at a resolution of 2.9 A by X-ray diffraction techniques. The overall structural organisation of the particle is similar to that seen in other picornaviruses but there are several unique features. Many of these help to explain its characteristic physical and biological properties. In particular the canyon or pit found at the surface of other picornaviruses is lacking, which has important implications for cell attachment and the process of infection. Also there are 60 large disordered protrusions at the surface corresponding to the major antigenic site. This disorder is of particular interest in relation to the striking ability of linear synthetic peptides to induce protective immunity against foot-and-mouth disease.  相似文献   
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One of the species that causes avian malaria is Plasmodium juxtanucleare. It is commonly found in poultry, especially when the birds receive food free of coccidiostats. Since industrial and organic poultry breeding is increasing in the world and few studies have been conducted examining the clinical parameters of both healthy and infected birds, this work evaluated whether the infection caused by P. juxtanucleare in Gallus gallus provokes alterations in the birds' hepatic profile. We analyzed the activity of ALT and AST and carried out histological analyses of liver sections of infected fowls by intracelomic inoculation with infected blood from a donor fowl with a parasite load of around 7%. The infected birds' parasite load was evaluated during 45 days by means of blood smears. There was a positive correlation between the increase in parasite load and higher ALT activity in the infected fowls, but there was no significant variation of the AST activity between the control and infected groups, possibly because of the non-specificity of this enzyme as an indicator of hepatic lesion. The results show that infection caused by P. juxtanucleare in G. gallus provokes hepatic alterations, indicated by the increase in the ALT enzyme activity and by the inflammatory infiltrates found in the liver sections of the infected fowls.  相似文献   
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This study investigates the composition and concentrations of volatile organic compounds (VOCs) in air-conditioned office space and low-level waste (LLW) repository sites of nuclear power plants located in Taiwan. Air samples were collected in the office space and technical rooms of administration buildings of the three nuclear power plants and in LLW repository site using canisters. Thirty-six toxic organic compounds including aromatics, CFCs and chlorinated hydrocarbons were identified and quantified using gas chromatograph/mass spectrometer (GC/MS). The results indicated that the concentrations of most determined species were similar to that in urban areas; however, the air at the LLW building contained abundant trichlorotrifluoroethane (CFC-113), trichloroethylene, toluene, 1,2,4-trimethylbenzene and CFC-12 in concentrations markedly higher than the background levels. Only toluene and 1,2,4-trimethylbenzene were detected with low concentrations in the air of LLW repository site. In addition, comparison of the ambient air concentration at several major industries and urban atmosphere revealed that the nuclear power plants emitted and/or leaked higher concentration of chlorinated hydrocarbons among them.  相似文献   
45.
Two varieties of finger millet (Eleusine coracana)-a tannin-containing red variety, CO13, and nontannin white variety, CO9-processed by treatment with enzymes (cellulase and hemicellulase) and fermentation with starters (from previously fermented finger millet batter), achieved the desirable goals of reduced fermentation time (12 h), increased acidity (2.2 to 2.4%), enhanced in vitro protein digestibility (IVPD) (14 to 26%), and mineral availability compared to 48 h uncontrolled natural fermentation (Usha Antony and Chandra, 1998). Fermentation with starters alone increased titratable acidity (1.02 to 1.88%), IVPD (5. 5 to 22%) and mineral availability, and decreased phytate (23 to 26%) and tannin (10.8 to 40.5%) in the millets. Enzymatic treatment (3 h, 50 degrees C) did not significantly alter the pH, phytate, tannins, IVPD, or HCl-mineral extractability but enhanced fermentative changes. Overall, the changes were marked when the 48 h starter was used and the improvements in nutrient availability was greater in the CO13 variety.  相似文献   
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The innate immune system of fish is considered first line of defense against a broad spectrum of pathogens. Being a component of innate immunity and lying at the interface between fish and the aqueous environment, skin mucus plays a frontier role in protecting fish from infections. In the present study, skin mucus of Cirrhinus mrigala, Labeo rohita, Catla catla, Rita rita and Channa punctata, inhabiting different ecological niches, was analyzed to characterize potential innate immune factors such as lysozyme, proteases, phosphatases, esterase and sialic acid. The enzyme activities were high in bottom dweller species, C. punctata and C. mrigala, and low in clean water inhabiting species, L. rohita and C. catla. An inverse relationship was observed between the level of enzyme activity and the sialic acid content in these fish species. In R. rita, however, the levels of all factors were found to be low. Zymographic analysis with labeled Micrococcus lysodeikticus revealed three isoforms of lysozyme in C. punctata and two in each species, C. mrigala, L. rohita and C. catla. In R. rita, lysozyme could not be detected. Gelatin zymography revealed that serine and metalloproteases were the major mucus proteases in all fish species investigated. In addition, trypsin-like protease and Ca(++)-specific serine proteases were observed in skin mucus. Increased knowledge of these parameters could be useful in understanding the role of skin mucus in the innate immune system of fish species inhabiting different ecological niches.  相似文献   
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Volatile fatty acid (VFA) production rates were measured by isotope dilution technique in the rumen of buffalo calves fed on wheat straw plus concentrate, green maize, cow pea and berseem. Correlations derived between the VFA production rates and their concentration and DOM were significant except in animals fed on cow pea. The VFA production rates were also significantly correlated with the TDN intake in all the four feeds tested.The regression equations obtained for the four feeds were different, which suggested that VFA production may vary with the quantity and quality of feed digested. These experiments suggest the use of different regression equations for different feeds.  相似文献   
50.
Human filariasis caused by Brugia malayi is still a public health problem in many countries of Asia including India, Indonesia, Malaysia and Thailand. The World Health Organization (WHO) has targeted to eliminate filariasis by the year 2020 by Mass annual single dose Diethylcarbamazine Administration (MDA). Results of the MDA programme after the first phase was less satisfactory than expected. Malayan filariasis caused by B. malayi is endemic in the south of Thailand where domestic cat serves as the major reservoir host. There is no report about the occurrence of B. malayi in dogs. The present work was carried out to find out the incidence of microfilariasis in dogs and also to detect the presence of human filarial infection in dogs, if any. One hundred dogs above 6 months of age presented to the veterinary college Hospital, Mannuthy, Kerala, with clinical signs suggestive of microfilariasis - fever, anorexia, conjunctivitis, limb and scrotal oedema - were screened for microfilariae by wet film examination. Positive cases were subjected to Giemsa staining, histochemical staining and molecular techniques. Results of the study showed that 80% of dogs had microfilariasis; out of which 20% had sheathed microfilaria. Giemsa and histochemical staining character, PCR and sequencing confirmed it as B. malayi. High prevalence of B. malayi in dogs in this study emphasized the possible role of dogs in transmission of human filariasis.  相似文献   
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