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101.
I would say that the ultimate position holders of the D.V.A. find themselves in, is very largely dependent on the course of events over the next few years and in no small measure to their own endeavours. I feel that the holders of the D.V.A. should view this training period as one in which they have enlarged their own over all appreciation of the subject they have studied and have therefore, gained for themselves a material advantage over other members of the profession who have not in fact followed this line of study and that although there is a certain amount of despondency in the ranks of the veterinary anaesthetists at the moment, this should not be allowed to become an obstacle in the progressive development of this group.  相似文献   
102.
Histochemical studies of normal and adenomatous intestinal mucosa of the pig showed the adenomatous epithelium to be deficient in enzymes normally found in mature absorptive cells. Electron microscopic studies confirmed that the adenomatous cells closely remsembled the crypt cells of normal mucosa.  相似文献   
103.
Inactivated rabies vaccines prepared from common vaccine strains of virus were inoculated into foxes by the intramuscular and intestinal route. There were differences among the vaccines in the duration of antibody produced after intramuscular administration. Inactivated vaccines deposited directly into the lumen of the duodenum by means of a fiberscope caused seroconversion in some foxes, especially following a booster dose, but the antibodies produced were for the most part of short duration. The ERA modified live virus vaccine, in contrast, produced a satisfactory and long lasting antibody after intestinal instillation.  相似文献   
104.
Breed, age, weight, type of work performed, seasonal onset, poor ventilation and exposure to moulds in the habitat were investigated in relation to the occurrence of chronic obstructive pulmonary disease (COPD). COPD was most commonly detected in showjumping and hacking horses. The older a horse, the more likely it was to become affected although most were 6 to 10 years of age. Of the horses in this sample of the population, which was not a random one, thoroughbred horses were affected least and ponies most often. The high incidence in ponies was related to their more frequent exposure to poor quality fodder and bedding. Most horses are exposed to the hazard of moulds, but more affected horses were so exposed than those not affected with COPD. Poor ventilation of the stable increased the chance of a horse becoming affected. Sex, body weight and season of onset of coughing had no influence on the occurrence of the disease.  相似文献   
105.
Joseph Lister     
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The UK Biodiversity Action Plan has identified the creation of lowland heathland as an important objective. Heathland restoration studies have identified soil pH, elevated soil nutrients and large weed seed banks as major problems in the restoration of heathland vegetation on ex-arable land. Heathland vegetation is usually found on nutrient-poor acidic soils. Creating acidic soil conditions on ex-arable sites thus may produce a suitable environment for the establishment of heath vegetation. Soil acidification by the addition of sulphur has been shown to reduce the soil pH and the availability of nutrients in arable soils. A series of experiments was established to investigate the effects of soil acidification using sulphur on the establishment of Calluna vulgaris and the development of weed vegetation. The application of sulphur at 0.24 kg m−2 to an arable soil was found to increase the survival rate of C. vulgaris cuttings planted in it. The mechanism of increased C. vulgaris survival appeared to be by sulphur application significantly reducing the cover of arable weeds arising from the soil seed bank. Higher rates of sulphur application (0.36 and 0.48 kg m−2) resulted in the death of many C. vulgaris plants. However C. vulgaris seedlings were able to establish successfully on these ex-arable soils within 18-24 months following the addition of these levels of sulphur. The application of sulphur appears to offer a practical solution to heathland creation on ex-arable land. However, it may be necessary to provide an interval of between 18 and 24 months between the application of sulphur and the addition of C. vulgaris plants or seeds for the successful establishment of heathland vegetation.  相似文献   
110.
This study was initiated to investigate the source of boron (B) accumulated in margins of old leaves of Curcuma ‘Chiangmai University Pride’ (‘CMU Pride’). Nutrient elements were analyzed from different parts of the rhizome before potting and from whole rhizomes at harvest, and different leaf locations of young and old leaves during forcing in coarse sand medium. Plants were fertilized with solutions lacking B during the forcing period. Leaf-margin burn symptoms in old leaves of ‘CMU Pride’ could result from the combination of high levels of B and low total N levels. High levels of manganese (Mn) may not be involved in leaf margin-burn symptoms. Boron accumulated in the outer region of the old leaves could result from following evaporation of gutatted water droplets containing dissolved B. High levels of B in the edge of the old leaves may not be transported from the rhizomes.  相似文献   
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