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951.
952.
Polyclonal antibodies were raised against polygalacturonases partially purified from culture filtrates of Aspergillus niger grown on sugarbeet pectin or polygalacturonic acid. An enzyme-linked immunosorbent assay (ELISA) for polygalacturonase was developed and the antisera were exploited in immuno-affinity chromatography to remove polygalacturonase from a mix of sugarbeet modifying enzymes. This approach has facilitated the preparation of an enzyme mix, containing a pectin deacetylase and demethoxylase together with an arabinofuranosidase, free from polygalacturonase, in a rapid, simple procedure.  相似文献   
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Analysis of the immunoadjuvant octadecyl tyrosine hydrochloride   总被引:1,自引:0,他引:1  
A simple, rapid, high performance liquid chromatographic (HPLC) method for the analysis of the immunoadjuvant octadecyl tyrosine hydrochloride is described. The HPLC procedure can be applied to the direct determination of amino acid reactants present as contaminants in the adjuvant (tyrosine, ethyl tyrosine) and from this information the content of octadecanol reactant can be estimated. Further, these same determinations provide a means of monitoring immunoadjuvant stability in any vaccine preparation.  相似文献   
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Characterization of bacteriophage SPP1 transducing particles   总被引:2,自引:0,他引:2  
Bacillus subtilis lysates produced by virulent bacteriophage SPP1 retained their transducing ability upon purification from contaminating PBSX particles. The buoyant density in CsC1 of the transducing activity was indistinguishable from that of the SPP1 plaque-forming units and the sedimentation behaviour in sucrose gradients of purified transducing particles was the same as that of SPP1 phage particles. Further, high concentrations of anti-SPP1 serum inactivated transducing particles and SPPl plaque-forming units at the same rate. The transduction process was resistant to DNAase treatment, but was enhanced by temperatures that did not allow transformation. It was concluded that particles of the size, shape, density and serum-sensitivity characteristic of SPP1, but carrying bacterial DNA, are vectors in a true transduction process. Cell survival upon SPP1 infection is discussed.  相似文献   
957.
Mycoplasma gallisepticum membrane proteins were separated by two-dimensional gel electrophoresis. We found no evidence for the presence of a membrane glycoprotein.  相似文献   
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Size related changes in muscle twitch kinetics, morphometrics and innervation have been examined in cod, Gadus morhua. Fish size ranged from 9 cm to 45 cm in total length (L).

Twitch contraction time (time to 90% relaxation), scaled in proportion to L0.29. Scaling of morphometric parameters was essentially geometric. Mean cross‐sectional area and weight of the myotomal muscle scaled in proportion to L2.05 and L3.08 respectively. These results are discussed in the light of alterations in length specific swimming performance and kinematics as fish grow.

During growth, the number of endplates terminating on each fast fibre increased, from around 10 on fibres 2 mm in length (~10 cm fish) to 20 on 10 mm fibres (—40 cm fish). However, mean spacing between endplates increased from around 0.25 mm to 0.50 mm. The functional significance of polyneuronal innervation in teleost fast muscle fibres is discussed.  相似文献   
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