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981.
- An enzymatic ‘reaction rate’ micro-method for the rapid routine estimation of D-B-hydroxybutyrate (D-B-HOB) in ruminant plasma, using an I.L. Multistat III centrifugal analyzer, is described.
- Reaction conditions were optimized to give a linear response for plasma D-B-HOB concentrations between 100 and 2500 μmoles per litre, at 30°C and pH 9.0.
- For the standardized method the within-run and between-run coefficients of variation for deproteinised ovine plasma were consistently less than 3.5%.
- There was good agreement between plasma concentrations obtained by the present method and both original U.V. end-point technique (r=0.927b=0.950) and a colorimetric end-point procedure (r=0.937. b=0.879).
- Utreated ovine and bovine plasma consistently exhibited high ‘blank’ activity and this was directly correlated with plasma lactate dehydrogenase (LDH) activity in both species (r=0.971; p<0.001 and r=0.949; p<0.001 respectively). The distribution of LDH activity in man was similar to sheep but, contrastingly, non-specific interference was extremely low in human plasma and unrelated to LDH. Horse, chicken and rat had negligible ‘blank” activity and comparatively low LDH levels. In both cattle and sheep non-specific interference was abolished by perchloric acid precipitation. In the sheep subtraction of ‘blank’ activity gave D-H-HOB concentrations for untreated plasma comparable to those in deproteinised samples. However, in the bovine, D-B-HOB levels remained significantly (t=6.44; p<0.001) higher even after ‘blank’ correlation. In contrast to man and other non-ruminants, perchloric acid precipitation is essential in ruminants to avoid false overestimation of plasma D-B-HOB levels.
- Plasma with EDTA as anticoagulant and serum gave concentrations of D-B-HOB approximately 60% lower, than samples containing heparin or oxalate/fluoride. However, heparin was associated with much higher (up to 50%) non-specific NAD rduction than oxalate/fluoride.
- High levels of acetoacetate (400–1000 μmoles per litre) reduced the recovery of D-B-HOB from ovine plasma by less than 10%. This effect was negated by the inclusion of hydrazine hydrates in the reaction mixture. Perchlorate ion concentrations above 25 μmoles per litre per test dramatically inhibited the assay in ovine plasma, and therefore precipitation conditions must be carefully controlled.
- Plasma with oxalate/fluoride as anticoagulant showed the greatest stability in storage; 24 hours at room temperature, one week at +4°C and at least one month at ?20°C.
982.
D. Gerling 《Phytoparasitica》1984,12(2):109-118
Wild and cultivated plants in the vicinity of Kibbutz Nahshon and a few additional locations in Israel were sampled for the presence ofBemisia tabaci Genna-dius (Homoptera: Aleyrodidae). The whiteflies, together with their parasites,Eretmocerus mundus andEncarsia lutea, were found to develop on numerous host species throughout the winter. Especially high levels were reached onLan-tana camara, Abutilon grandifolium andIpomoea batatas. During late winter and spring the population on these hosts declined. From April onwards the populations increased on potatoes and sunflowers. 相似文献
983.
The known information on hymenopterous parasites of Nitidulidae was consolidated in this article. Species of parasites, nitidulid hosts and, where possible, plant host of the nitidulids are provided along with citations to sources of information. Thirty-three species of hymenopterous parasites are recorded in nine different families. Since nomenclature of several of the parasites has changed, it was updated with the assistance of specialists. 相似文献
984.
P. H. M. Roseboom D. Peters 《European journal of plant pathology / European Foundation for Plant Pathology》1984,90(4):133-141
Beet yellows virus can be detected in leaf extracts of infected sugarbeet plants by ELISA. The use of discs was studied and proved to be a valuable and qualitatively reliable method. Leaf material could be stored at 4o or 22°C for at least six days without affecting the detection of this virus by ELISA. A dramatic decrease in ELISA values was found when leaf extracts were frozen.In an analysis of the distribution of virus over the plant it was found that young leaves present at the moment of infection and those which had still to develop after infection will contain virus. Symptoms produced by systemic virus invasion occur on the oldest leaves containing virus.Samenvatting Het bietevergelingsvirus kan op betrouwbare wijze met de ELISA methode in geïnfecteerde bieteplanten worden aangetoond. Een aanzienlijke vereenvoudiging van de procedure kan worden bereikt met de zogenaamde disc-method, waarbij intacte ponsstukjes in de putjes van de ELISA-plaat worden geïncubeerd. Hierbij komt voldoende virus uit de ponsstukjes voor ELISA vrij. Bladmateriaal kon op verschillende wijzen bewaard worden zonder dat de mogelijkheid om het virus aan te tonen achteruitging. Met bladextracten die ingevroren waren, werden echter slechte resultaten verkregen.In een analyse naar de verdeling van het virus over het loof bleek het virus voor te komen in de geïnoculeerde bladeren, in die bladeren die op het tijdstip van inoculatie minder dan de helft van hun uiteindelijke lengte bereikt hadden en in de bladeren die nog moesten verschijnen. De symptomen ontwikkelden zich op de oudste systemisch geïnfecteerde bladeren. 相似文献
985.
Clinical hypocalcaemia was associated with single doses of three oi more days; supply of zinc oxide to dairy cows for facial eczema control. Experimental hand dosing of a single dose of zinc oxide (40 and 120 mg Zn/kg b wt) to Jersey cows caused a significant drop in serum calcium concentration at 24 h followed by a rise to concentrations higher than controls at subsequent samplings over four days. At the highest zinc dose rate, 78% of serum calcium values were equal to or lower than the lowest control value at 24 h post dosing. Serum magnesium concentrations had a reciprocal relationship to the calcium levels at all samplings. Serum zinc concentrations were most elevated over the 48 h post dosing, returning to normal levels at the fifth day. Following the highest zinc dose milk yields were reduced by approximately 1.5 kg milk/cow/day for 48 h. Similar results were obtained when cows grazed pasture on which large amounts of zinc oxide had been sprayed. 相似文献
986.
Two lactational intramammary antibiotic preparations (cloxacillin and oxytetracycline) were each used to treat eight goats by intramammary infusion in one half. The rate of release of the antibiotics was monitored by a diffusion assay based on the sensitive organism Bacillus stearothermophilus var. calidolactis. Cloxacillin was still detectable 156 hours after the final treatment while oxytetracycline was undetectable 108 hours following treatment. A small but significant amount of antibiotic was translocated between treated and untreated halves of the udder in both cases. 相似文献
987.
The pharmacokinetics of fenbendazole and oxfendazole in cattle are described. The pharmacokinetics of oxfendazole were not significantly different when administered orally and by intra-ruminal injection. At a dose rate of 4.5 mg/kg, administered orally, fenbendazole gave rise to mean peak concentrations in plasma of fenbendazole and oxfendazole of 0.11 and 0.13 g/ml respectively. Oral administration of oxfendazole, at 4.5 mg/kg body weight, gave rise to plasma peak concentrations of fenbendazole and oxfendazole of 0.10 and 0.20 g/ml respectively. Following intra-ruminal administration of oxfendazole, the peak concentrations were 0.11 and 0.18 g/ml respectively. 相似文献
988.
A study of the interaction between bromocresol green dye and bovine,ovine and equine serum globulins
In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds.In the present study, serum albumin values obtained from three animal species by the immediate, i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied.In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the immediate BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye. 相似文献
989.
990.