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141.
Practitioners commonly submit samples from dogs for partial thromboplastin time and prothrombin time determinations. Controversy exists as to the necessity for rapid separation of plasma and cells, and submission of the plasma on ice (or frozen). The purpose of this study was to address three questions. First, is it better to submit plasma or is whole blood satisfactory? Second, is it necessary to refrigerate the sample or is maintenance at room temperature (20° C) adequate? Third, does the sample have to arrive at the laboratory within a few hours of collection or can reliable partial thromboplastin time/prothrombin time determinations be made on samples up to 48 hours old?It has been shown by this study that reliable partial thromboplastin time and prothrombin time determinations can be carried out on canine plasma for up to 48 hours after collection regardless of whether or not the plasma is separated immediately; however the samples must be kept at 4°C. If the samples are maintained at room temperature, reliable prothrombin time determinations can be obtained for up to six hours after collection regardless of whether or not the plasma is separated immediately. Reliable partial thromboplastin time determinations can be made on plasma stored at 20°C for up to 24 hours after collection and possibly longer (up to 48 hours) if the plasma has been separated immediately.  相似文献   
142.
An endoscopic survey was performed to assess arytenoid cartilage movement during quiet respiration in 48 Clydesdale horses. Physical characteristics which could influence the length of the recurrent laryngeal nerves were also recorded from these horses and the relationship of these characteristics to the presence of abnormal left arytenoid cartilage movements was assessed statistically. Some degree of abnormal arytenoid movement was observed in 50% of the animals over one year of age. No significant correlation between sex, age, estimated weight, height, or neck length could be found although affected animals were, on average, slightly taller, lighter and longer necked.  相似文献   
143.
1. Broilers were fed on wheat‐casein or wheat‐soyabean meal diets and the excreta collected after 12 and 24 h. Samples of excreta were freeze dried or dried in a force draught oven at 60 or 80 °C.

2. Drying procedure and collection time significantly influenced the determined energy and nitrogen concentrations of the excreta.

3. Drying excreta in an oven at 60 °G proved at least as effective as freeze drying for the majority of amino acids.  相似文献   

144.
1. The effect of feeding the detergent, sodium lauryl sulphate at concentrations up to 10 g/kg diet on egg‐shell quality was examined in laying hens at 24, 36 and 48 weeks of age.

2. Lauryl sulphate at 2.5 g/kg or more in the diet significantly increased shell breaking strength, shell thickness and shell weight at 24 and 36 weeks. In 48‐week‐old hens only shell breaking strength was increased significantly. Egg production and egg weight were not affected significantly by lauryl sulphate.

3. Lauryl sulphate might increase these measures of quality by increasing shell deposition and/or shell elasticity.  相似文献   

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Field treatments in a vineyard with 0.015 or 0.01% a.i. of cypermethrin, fenvalerate, fenpropathrin or AC-222,705 were more efficient in controlling the grape-berry moth (Lobesia botrana Schiff.) and the honeydew moth (Cryptoblabes gnidiella Mill.) than four standard treatments consisting of two with 0.05% a.i. fenitrothion and two with 0.075% a.i. diazinon. In pyrethroid-treated plots, infestation at the end of the trials ranged between 2.5 and 12%, compared with 21% in the standard treatment plots and 34% in the untreated plots. Cypermethrin, fenpropathrin and AC-222,705 exhibited similar field activity, while that of fenvalerate was somewhat lower. Under laboratory conditions, cypermethrin at 0.005 and 0.01% a.i. was significantly more potent than fenvalerate, fenpropathrin and AC-222,705; at a higher concentration, 0.015% a.i., all pyrethroids were highly active, with mortality ranging between 75 and 95%. Under laboratory conditions the vinegar fly (Drosophila melanogaster Meig.) was in general more susceptible to pyrethroids than was the grape-berry moth. Cypermethrin and AC-222,705 at 0.005% a.i. and avermectin at 0.0035% a.i. were potent compounds against the vinegar fly and more active than fenvalerate and fenpropathrin.  相似文献   
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Summary. The translocation of 14C-labelled herbieides in field bracken has been sludied in some preliminary experiments by means of autoradiography. A detailed account is given of the methods employed. It is shown that when 2,4-D is applied to fronds at different stages of development movement of the tracer into the rhizome is considerably greater from parts of the frond which are still immature. Trasnslocation within the frond is predominantly basipetal at all stages of development; within the rhizome the direction of movement appears to be determined primarily by the nature of the vascular connections with the treated pinna.
In a comparison between the translocation of 2,4-D, 4-CPA and dalapon no difference was apparent after 24 hours, but when the treatment period was extended to 96 hours there was evidence that 4-CPA bad been translocated in a considerably greater amount than either of the other two herbicides.
Rechrches iréliminaires sur la migration des herbieides marqués am 14 C dans la fougrère algle (Pteridium aquilinum)  相似文献   
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