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141.
142.
Lancaster N 《Science (New York, N.Y.)》1988,241(4862):233-234
143.
Proctor RN 《Science (New York, N.Y.)》1988,241(4866):730-731
144.
An experimental technique is described for simultaneously measuring the static and dynamic interactions of very thin liquid films between two surfaces as they are moved normally or laterally relative to each other. Film thickness can be measured and controlled to 1 angstrom. Initial results are presented of the transition in the physical properties of liquid films only one molecular layer thick to thicker films whose properties are practically indistinguishable from the bulk. In particular, the results show that two molecularly smooth surfaces, when close together in simple liquids, slide (shear) past each other while separated by a discrete number of molecular layers, and that the frictional force is "quantized" with the number of layers. 相似文献
145.
Infertility in a ram associated with a knobbed acrosome abnormality of the spermatozoa 总被引:1,自引:1,他引:0
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Savage NC 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(3):126-127
A yearling Rambouillet ram with an asymmetrical scrotum was examined for potential breeding soundness prior to use in a synchronized mating program in a purebred flock of 20 ewes. Initial sperm cell evaluation revealed 78% knobbed acrosomes associated with few other abnormalities of the head and midpiece. Use of the ram resulted in no conception in one group of ten synchronized ewes. One month later, the proportion of sperm cells with knobbed acrosomes was 80%. 相似文献
146.
Les différentes bandes de contention utilisées pour la confection de prothèses externes chez les petits animaux
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Bonneau NH Olivieri M 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(5):199-200
The various orthopedic casting tapes used for external fracture fixation in small animals. 相似文献
147.
Adetunji A Pascoe PJ McDonell WN Horney FD 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(9):342-346
A retrospective morbidity and mortality study was carried out on 125 case records of cattle involving xylazine/halothane anesthesia at the Ontario Veterinary College, Guelph between May 1979 and February 1983. 相似文献
148.
Breton L Bonneau NH Beauregard M 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(11):426-428
An osteosarcoma of the femoral diaphysis associated with the presence of a bone plate in a dog 相似文献
149.
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
150.
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