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51.
The science of control of infectious diseases in hospitals was born in 1847 when Semmelweis, a physician, ordered his medical students to scrub their hands in chlorinated lime water between patients and demonstrated that this simple procedure resulted ina dramatic decline in patient morbidity and mortality. In the late nineteenth century came huge breakthroughs in the understanding that microorganisms cause many disorders, and methods to eliminate and control these microorganisms were attempted. By 1910, sterile instruments, gowns, masks, and gloves had become standard for surgical procedures in large university human hospitals, and isolation of human and veterinary patients with contagious diseases became standard. With the advent of vaccines, many epidemic viral diseases could be controlled, and antimicrobial drugs allowed many previously devastating bacterial diseases to be treated effectively. Before long, however, bacterial resistance became an important issue and remains so today, particularly for Salmonella and Staphylococcus aureus in horses. Vaccination has decreased the number of animals susceptible to equine influenza and equine herpesvirus 1, yet these contagious diseases still pose a serious issue in large equine veterinary hospitals. The development of equine isolation facilities and improved methods of barn cleaning; mandatory application of procedures, such as handwashing or use of disinfectant hand wipes, to prevent the spread of infectious diseases; and monitoring of antimicrobial resistance and use of restricted antimicrobial drugs were driven by recognition and necessity and have given rise to current equine infection control programs.  相似文献   
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AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.  相似文献   

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Turtles have long served man as an important food resource in Amazonia. During the colonial period, Portuguese traders disturbed nesting beaches on a large scale in search of eggs which were converted into oil for cooking and lighting. Exploitation was increasingly intense by the end of the 19th century and turtle populations had declined drastically. Although legislation has been passed to protect them, enforcement is lax and turtles face increasing pressure from man not only for food but as a result of habitat disturbance.  相似文献   
55.
Evolution of C2H4 from soils under anaerobic conditions was stimulated by amendment with cereal straw, but hay had little effect. Temporary restoration of aerobic conditions resulted in large increases in C3 and C4 hydrocarbons, with both straw and hay amendments. Several known products of the fermentative degradation of carbohydrate increased the evolution of hydrocarbons under anaerobic, and to a greater extent, under aerobic conditions. In particular, ethanol and butyric acid promoted the formation of C2H4 and propylene, respectively. The association between degradation products and C2H4 suggests that both may be implicated when root growth is adversely affected by the anaerobic decomposition of plant residues.  相似文献   
56.
Cutting patterns producing high and low areas were imposed on swards of Dactylis glomerata and Lolium perenne to test whether output could be increased when compared with traditional uniform cutting methods. In two experiments, swards of both grasses were divided into parallel 9 cm strips which were cut alternately on different occasions to a height of 5 cm. These swards yielded a similar quantity of herbage DM to that from other swards cut uniformly at the same height and frequency. In a third experiment, swards of Lolium perenne were divided into alternate strips of unequal width (9 and 4.5 cm). The narrow strips were allowed to grow to a height of 15 cm and were occasionally trimmed at this height. The wide strips were cut to 5 cm at 2–or 4–weekly intervals. Areas cut to 5 cm every 2 weeks yielded significantly more DM when adjacent to high areas than when adjacent to areas cut to 5 cm every 2 weeks (i.e. under uniform cutting). The interaction between adjacent areas having different defoliation regimes is discussed in relation to the possibility of obtaining some additional output from a suitable no niform cutting system compared with uniform cutting. Sward productivity under no niform grazing patterns of livestock is also discussed.  相似文献   
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Winter (vernalized) and summer (non-vernalized) timothy tillers were grown to anthesis in day/night temperature regimes of 32/26°, 27/21°, 21/15°, and 15/10°C. Herbage and total plant yields, total leaf-blade number and area, and total plant growth-rate were highest, or very nearly so, in the 21/15°C regime for both the winter and summer plants. However, summer plants reached anthesis 13 to 14 days later than winter plants in each temperature regime. Even though virtually all primary shoots produced an infiorescence, summer plants had significantiy more leaves and leaf-blade area, produced significantiy higher yields of leaf blade, stem plus sheath, stubble, and root tissues and had a significantly higher total plant growth rate than winter plants in each temperature regime.  相似文献   
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