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1.
Infection of striped mullet (Mugil cephalus) with Aeromonas hydrophila results in an acute septicemic disease. The disease can be experimentally induced by intramuscular injection, skin or gill scarification or by the oral route using pellets purposely seeded with bacteria. The organism was isolated from the blood 1–2 days after infection and from all organs 24 hr or longer after infection. The disease is characterized by early inflammatory and proliferative changes and later necrotic changes. Enteritis and hepatic necrosis are constant findings in aeromonad disease of M. cephalus but surface lesions are not pathognomic for these infections in mullet. Death of infected fish may be attributed to bacterial toxins which cause necrosis of parenchymal organs and soft tissue structure.  相似文献   
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We describe the postnatal ontogeny and localization of insulin-like growth factors I and II (IGF-I and -II) in the rat. We have used oligodeoxyribonucleotide probes for in situ hybridization (hybridization histochemistry) and for Northern blotting. IGF-II mRNA is strongly expressed in liver, skeletal muscle, perichondrium, leptomeninges and choroid plexus of the newborn. Demonstrable levels fall dramatically in the liver at 18-20 days postnatally but persist for longer periods in muscle and remain undiminished throughout life in the pia/choroid plexus, indicating that different control mechanisms operate in these tissues. IGF-I mRNA is predominantly found in the liver. Its level in this organ rises well before levels of IGF-II fall. This suggests that distinct factors govern the expression of IGF-I and -II genes.  相似文献   
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A novel method has been developed to allow cloning of protein targets for receptors with tyrosine kinase activity. By utilizing the carboxy-terminal tail of EGF receptor (EGFR) as a probe to screen lambda gt11 expression libraries, several EGFR-binding proteins have been cloned; two have been analyzed and contain unique SH2 and SH3 domains. One gene (GRB-1) has been fully sequenced, is expressed in various tissues and cell lines, and has a molecular mass of 85 kd. Interestingly, GRB-1 encodes the human counterpart of the PI3 kinase-associated protein p85. Advantages of this technique include the ease of cloning tyrosine kinase receptor targets present at low levels and the ability to identify proteins that are related in their capacity to bind activated receptors but contain no significant DNA sequence homology. This method, termed CORT (for cloning of receptor targets), offers a general approach for the identification and cloning of various receptor targets.  相似文献   
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Summary Seeds from 27 wild strains (18 tetraploids and 9 diploids) of Glycine weightii were germinated at a pH range of 5 to 8. The differences in germination (%) between all the strains were highly significant but between pH levels they were only nearly significant (P=0.067) with no interaction between pH levels and strains. Mean germination (%) for all tetraploids seems to be slightly higher ( 2%) than that for all diploids, especially at pH's 5, 7 and 8 but this may be due to the significantly longer time ( one day) it took tetraploids to complete germination. The apparent inverse relationship between seed weight and germination (%) was not significant.Mean germination time was highly significant for strains, pH's and their interaction. Increasing mean germination (%) resulted in decreasing mean germination time among strains. Large seeds took less time to germinate especially those from some of the tetraploid strains. This indicates that it is possible to produce a variety with high germination (%), fast germination rate and possibly large seeds. If the marked difference in pH tolerance among strains will prove to be mainly hereditary, then it will be also possible to select for either specific pH tolerance or tolerance at a wide range of pH.  相似文献   
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We have analyzed, by means of density functional theory calculations and the embedded cluster model, the adsorption and spin-state properties of Cr, Ni, Mo, and Pt deposited on a MgO crystal. We considered deposition at the Mg2+ site of a defect-free surface and at Li+ and Na+ sites of impurity-containing surfaces. To avoid artificial polarization effects, clusters of moderate sizes with no border anions were embedded in simulated Coulomb fields that closely approximate the Madelung fields of the host surfaces. The interaction between a transition metal atom and a surface results from a competition between Hund's rule for the adsorbed atom and the formation of a chemical bond at the interface. We found that the adsorption energies of the metal atoms are significantly enhanced by the cation impurities, and the adsorption energies of the low-spin states of spin-quenched complexes are always more favorable than those of the high-spin states. Spin polarization effects tend to preserve the spin states of the adsorbed atoms relative to those of the isolated atoms. The metal–support interactions stabilize the low-spin states of the adsorbed metals with respect to the isolated metals, but the effect is not always enough to quench the spin. Spin quenching occurs for Cr and Mo complexes at the Mg2+ site of the pure surface and at Li+ and Na+ sites of the impurity-containing surfaces. Variations of the spin-state properties of free metals and of the adsorption and spin-state properties of metal complexes are correlated with the energies of the frontier orbitals. The electrostatic potential energy curves provide further understanding of the nature of the examined properties.  相似文献   
7.
In the present study, we extend our novel concept of designing and using exogenous markers for the characterization of oxidative stress (OS) and OS-associated diseases. The aim was to use such a synthetic compound as a tool for studying OS in blood from diabetic and hypercholesterolaemic (Hc) patients. The marker used N-linoleoyl tyrosine (LT) was constructed from tyrosine and linoleic acid (LA); both components are known to be easily oxidized upon exposure to different types of reactive oxygen/nitrogen species (ROS/RNS), and to generate specific oxidized products, depending on the type of oxidants present in vivo. Using the LT probe, we showed that the ratios of oxidized LT to total LT (Ox-LT/LT) is significantly higher in blood samples obtained from diabetic patients, than in Hc patients or healthy control subjects. LC/MS analysis revealed that blood from diabetic patients oxidizes the marker with predominant formation of Ox-LT hydroperoxide (LT-OOH) and epoxide (epoxy-LT), where the LA moiety is oxidized to hydroperoxide and to epoxide, respectively. Analysis of oxysterol levels in these samples (GC/MS) revealed that the blood of both diabetic and Hc patients contained significantly more oxysterols than blood of control subjects. Consumption of pomegranate juice by diabetic patients for 3 months suppressed their blood capacity to oxidize the LT and similarly also reduced their blood oxysterol/total cholesterol ratio by 93%. The use of an exogenous marker to characterize OS in blood samples yields important information on the extent of OS, and can provide a fingerprint for the early identification of different pathological conditions associated with OS.  相似文献   
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This work aimed to co-digest various wastes to assess the best combination of all mixing ratio, also at choosing the best ratio between untreated primary sludge (UPS) singly from two sources, (South valley University (SUPS) and Abu tesht wastewater station (AUPS) and raw chicken manure (RCM) and comparing the results in either case. The co-digestions of untreated primary sludge from Abu tesht wastewater treatment stations with different levels of raw chicken manure (0:100, 10:90, 30:70, 50:50, 90:10, and 100:0) to obtain the best mixtures. Also, co-digestion of untreated primary sludge from south valley university with different levels of raw chicken manure at the same ratios, to obtain the best mixtures. Batch digestion tests were applied in 2.5 L digester with a working volume of 2.0 L. The samples in triplicates were separately loaded into the digesters locally fabricated and kept for 20 days as a retention period and diluted with the same amount of water. Mesophilic under 35 °C was adopted for untreated primary sludge as well as mixtures with raw chicken manure based on total solids (TS) and volatile solid (VS) proportions. The average biogas yields from AUPS/RCM mixture obtained ranged from 8570 to 5600 ml, by the following descending order, 10: 90 > 90:10 and so on >100:0, and the average biogas yields from SUPS/RCM obtained ranged from 6330 to 5635 ml, in the order of 90: 10 > 10:90 and so on >100:0. The results showed highest biogas yield from AUPS/RCM and SUPS/RCM mixtures with mixing ratio of 10:90 and 90:10, respectively, however, the lowest biogas production detected in separate digestion of AUPS and SUPS. The results indicated that co-digestion between the sludge and raw chicken manure could increase total biogas production volume, enhance sludge treatment process, and produce eco-friendly sludge because of co-digestion process than separate processing of each feedstock.  相似文献   
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