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2. At spoilage the main organisms at 2 and — 1 °C on the carcasses wrapped in the oxygen‐permeable film were pseudomonads, producing unacceptable “off odours” when their numbers were >108/cm2. This occurred in about 10 d at 2 °C but in about 19 d at ‐ 1° C.
3. The effect of wrapping in the heat‐shrunk oxygen‐impermeable film was to delay or inhibit the growth of pseudomonads and thus extend the shelf‐life by more than 50% at either temperature. The predominant organisms isolated from the spoiling carcasses were atypical lactobacilli and enterobacteria.
4. Sensory assessment of the carcasses stored at — 1 °C by a trained panel indicated that, although less obvious “ off odours “ were produced by the micro‐organisms growing on the carcasses wrapped in the impermeable film, differences were detected at 33 d when the numbers of bacteria reached about 107/cm2 whilst at 41 d the meat was described as rancid. 相似文献
2. It was found that Streptococcus faecalis sub‐species liquefaciens predominated in chicks prior to feeding and in control birds the organism remained as a significant part of the flora throughout the experiment.
3. Strep. faecalis s.s. liquefaciens was not found after the first week in birds given dietary bacitracin.
4. Although outnumbered initially in the caeca by Strep, faecalis s.s. liquefaciens, other streptococci were present at 106 to 107/g contents from 14 d onwards in both control and bacitracin‐treated birds; these included Strep. faecium biotypes and two other unidentified but related groups.
5. Tests made in vitro showed that Strep. faecalis s.s. liquefaciens was more sensitive to bacitracin than Strep. faecium.
6. The possible effects of Strep. faecalis s.s. liquefaciens on the developing bird are discussed. 相似文献
Materials and Methods: Stored serum and plasma samples from normal cats, cats with various neoplasms, and cats with non‐neoplastic disease were evaluated with a commercial ELISA kit (R&D Systems, Minneapolis MN). Samples were run in duplicate, and a standard curve was performed for each plate. The data were analyzed for differences between populations, and between serum and plasma levels in the same patient to determine the optimal sample for evaluating VEGF in cats.
Results: In seven apparently healthy cats mean plasma VEGF was 95.6 pg/mL. In non‐neoplastic disease (7 cases), mean plasma VEGF was 117.3 pg/mL and mean serum VEGF level was 219.7 pg/mL. In ten tumor‐bearing patients mean plasma VEGF was 247.1 pg/mL, and mean serum VEGF was 322.3 pg/mL. Statistical analysis showed no significant difference between mean serum and plasma VEGF concentrations within each group or between groups (p > 0.05).
Discussion: Serum and plasma VEGF levels could not be used to distinguish between healthy cats and cats with neoplastic or non‐neoplastic disease. 相似文献