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A new medium containing sodium tripolyphosphate, ethylenediaminetetraacetic acid disodium salt, dihydrate, sodium desoxycholate, supplemented with minerals and nutrient sources was developed, which was very effective in inhibiting swarming of Bacillus spp. This medium polyphosphate-EDTA-desoxycholate agar (PEDA) was compared with tryptone glucose extract agar (Oxoid) for determining the total plate count of various semi-conserved fishery products. While promoting discrete colony formation of Bacillus spp., PEDA provided good bacterial recovery. PEDA is recommended for isolation or enumeration of bacteria in food dominated by swarming Bacillus spp.  相似文献   
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Reviews in Environmental Science and Bio/Technology - Agriculture is the basic necessity all over the world which provides food for the existence of humans. India is expected to be home to 1.6...  相似文献   
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Length weight relationships (LWRs) were estimated for four species of low value fishes that belongs to four families from the southwest coast of India. The specimens of, Callionymus margaretae, Dactyloptena peterseni, Rogadius serratus and Minous inermis were collected for a period of 1 year from the fishing trawlers of Cochin Fisheries Harbour (Lat. 09° 56′ 327″ N, Long. 76° 15′ 764″ E). The estimated allometric coefficient b values ranged from 2.5020 (Rogadius serratus) to 3.2438 (Dactyloptena peterseni) and r2 values ranged from 0.9492 (Rogadius serratus) to 0.9869 (Dactyloptena peterseni). All the LWRs were highly significant, with p < .001.This study provides the first estimate of LWRs for these low value by catch fish species.  相似文献   
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The solid-state photo-CIDNP (photochemically induced dynamic nuclear polarization) effect is studied in photosynthetic reaction centers of Heliobacillus mobilis at different magnetic fields by 13C MAS (magic-angle spinning) NMR spectroscopy. Two active states of heliobacterial reaction centers are probed: an anaerobic preparation of heliochromatophores (“Braunstoff”, German for “brown substance”) as well as a preparation of cells after exposure to oxygen (“Grünstoff”, “green substance”). Braunstoff shows significant increase of enhanced absorptive (positive) signals toward lower magnetic fields, which is interpreted in terms of an enhanced differential relaxation (DR) mechanism. In Grünstoff, the signals remain emissive (negative) at two fields, confirming that the influence of the DR mechanism is comparably low.  相似文献   
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Mice lacking both c-Jun-NH(2)-terminal kinases (JNK1 and JNK2) were generated to define their roles in development. Jnk1/jnk2 double mutant fetuses die around embryonic day 11 (E11) and were found to display an open neural tube (exencephaly) at the hindbrain level with reduced apoptosis in the hindbrain neuroepithelium at E9.25. In contrast, a dramatic increase in cell death was observed one day later at E10.5 in both the hindbrain and forebrain regions. Moreover, about 25% of jnk1-/-jnk2+/- fetuses display exencephaly probably due to reduced levels of JNK proteins, whereas jnk1+/-jnk2-/- mice are viable. These results assign both pro- and anti-apoptotic functions for JNK1 and JNK2 in the development of the fetal brain.  相似文献   
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By regulating the differential expression of proviral pre mRNA in the host cell, Rev plays a crucial role in the HIV-1 life cycle. The capacity of Rev to function is intimately linked to its ability to self-associate. Nevertheless, little is known about the exact role of self-association in the molecular mechanism defining its biological activity. A prerequisite knowledge is a definition of the molecular events undertaken by Rev during the process of self-assembly. Thus, this study was initiated to monitor the structure of Rev as a function of protein concentration. Rev undergoes a structural transition as a consequence of self-assembly. This structural transition was monitored by three spectroscopic methods. The accessibility of the single tryptophan in Rev monomer to acrylamide quenching increases with decreasing protein concentration. At very low concentration of Rev, the tryptophan accessibility is close to that of an unfolded Rev. As evaluated by circular dichroism, the secondary structure of Rev is protein concentration dependent as evidenced by an increase in the magnitude of ellipticity with increasing protein concentration. Further, results from ANS binding studies indicate that the ANS binding sites in Rev experience an apparent increase in hydrophobicity as the Rev concentration was increased. These concentration dependent changes seem to reach a maximum above 5 microM Rev monomer concentration. In order to define the mode of Rev self-association sedimentation velocity and equilibrium experiments were conducted. There are evidently two consecutive progressive association processes. At protein concentrations below 0.5 mg/ml, the data from sedimentation studies can be fitted to a single isodesmic model. Simulation of velocity sedimentation profile indicates that free Rev monomer that has not entered into the association processes can best be described to exhibit a value of S(20,w) that is substantially smaller than 1.4 S, a value needed to fit the rest of the data. The latter value is consistent for a Rev monomer with the expected molecules weight and if it were to assume a compact globular shape. These spectroscopic and hydrodynamic results imply that monomeric Rev is in a molten globule state, which becomes more compact upon self-association.  相似文献   
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