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91.
As with any pesticides, it is recommended that the environmental safety of a rodenticide is assessed in a stepwise manner, i. e. from basic laboratory studies on chemical behaviour and toxicology, through more detailed, specifically designed, studies of the compound's potential environmental hazard, to field experiments if they are shown to be necessary by the results of the lower tier studies. Following the release of the rodenticide onto the market, its environmental safety should be continually monitored through a formalized system for investigating any reports of wildlife death as a result of pesticides.  相似文献   
92.
Thirty dogs with primary lung tumours and six dogs with lymphomatoid granulomatosis were referred to the University of Bristol Veterinary School between 1970 and 1985. Clinical, radiographic and pathological findings were recorded in each case. Analysis of these findings allowed assessment of those features most helpful in reaching a definitive diagnosis and prognosis in such cases.  相似文献   
93.
A model simulating acute-compressive spinal cord trauma at the second lumbar spinal cord segment (100 g, 300 seconds) was used to evaluate the efficacy of a vehicle control, methylprednisolone sodium succinate (MPSS), and a 21-aminosteroid compound (U74389G). Dogs were allocated into one of five treatment groups (A to E) using ultrasonographic determination of spinal cord diameters to ensure even distribution of spinal cord diameters among the treatment groups. Initial dosages of the vehicle control (A), methylprednisolone (30 mg/kg of body weight) (B), or U74389G (30 mg/kg, 3 mg/kg, or 10 mg/kg of body weight) (C, D, or E, respectively) were administered intravenously 30 minutes after trauma. Dosages were reduced by one-half for 2 and 6 hour treatments. Then every 4 hours for 42 hours, dosages were reduced one-third and one-sixth from the original dose of methylprednisolone and U74389G, respectively. Neurological examinations were performed daily for 21 days. Histopathological examination of the traumatized spinal cord showed malacic and degenerative lesions. Although significant differences in some portions of the neurological and histopathologic examinations were observed, clinical efficacy for MPSS and U74389G could not be established in this model.  相似文献   
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Twelve mixed-breed swine (26.5-42.5 kg) received three daily intramuscular (i.m.) doses of 14C-ceftiofur hydrochloride. Three males and three females, received 6.76 ± 0.83 mg of 14C-ceftiofur free acid equivalents (CFAE)/kg body weight (b.w.)/day, while the other group received 4.41 ± 0.97 mg-CFAE/kg b.w./day. The swine were slaughtered 12 h following the last dose. Total dose accountability for the 6.76 mg dose was 91.44 ± 16.11% (72.51% in urine; 12.63% in faeces). For the 4.41 mg dose, accountability was 100.35 ± 20.45% (82.48% in urine; 12.85% in faeces). Within the tissues used for residue monitoring, the highest concentrations were observed in the kidneys (10.68 and 6.33 μg-CFAE/g for the 6.76 and 4.41 mg doses, respectively), followed by the injection sites, lungs, liver and muscle. In a separate study, twelve mixbreed swine (23.1-39.7 kg) received 14C-ceftiofur hydrochloride at 3.08 mg-CFAE/kg b.w. once daily for 3 days. Two males and two females were slaughtered at either 12, 72 or 120 h after the last dose. Total dose accountability for the 3.08 mg dose was > 83% (> 68% in urine; > 13% in faeces). In swine slaughtered 12 h after the last dose, residue concentrations closest to the safe concentrations were observed in the kidneys (3.62 μg-CFAE/ g), followed by the injection sites, lungs, liver and muscle.  相似文献   
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Objective— To report technique, surgical time, complication rate, and postoperative activity in dogs undergoing 2 intracorporeally-sutured total laparoscopic gastropexy (TLG) techniques compared with a laparoscopic-assisted gastropexy (LAG) technique.
Study Design— Randomized clinical trial.
Animals— Dogs (n=30) weighing >25 kg.
Methods— Dogs were randomly assigned to 1 of 3 groups. Two TLG techniques were performed using a median 3 portal technique. One of 2 suturing techniques was used to approximate corresponding incisions made in the stomach and body wall; using intracorporeal hand-suturing or a suture-assist device (Endostitch). In a 3rd group, a previously reported LAG technique was used. All dogs had an activity monitor placed for 7 days pre- and postoperatively. Linear regression analyses were performed to evaluate the association of surgical procedure on gastropexy time and the percentage change in activity counts.
Results— Median gastropexy time was 28 minutes (range, 20–41 minutes) for LAG, 48 minutes (range, 39–61 minutes) for the hand suture TLG technique, and 56 minutes (range, 30–90 minutes) for the Endostitch TLG technique. LAG was performed faster than TLG ( P <.05). LAG dogs had a greater decrease in postoperative activity than TLG dogs ( P =.005); however there was no difference in surgical time or postoperative activity between TLG techniques.
Conclusions— TLG can be performed safely and effectively in dogs and although it takes longer, it has less impact on postoperative activity compared with LAG.
Clinical Relevance— TLG techniques may have advantages over LAG as measured by a greater willingness of dogs to move around postoperatively.  相似文献   
99.
Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events-the rapid warming that marks the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation-are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres.  相似文献   
100.
Ten healthy adult mares were given a single intramuscular dose (2.2 mg/kg) of gentamicin sulfate. Over a 48-h period, gentamicin concentrations were measured serially in the serum of all ten mares and in synovial fluid, peritoneal fluid, and urine of six of the mares. The mean peak serum gentamicin concentration was 5.73 μg/ml at 1 h. Gentamicin was detected in synovial fluid and peritoneal fluid, with mean peak gentamicin concentrations of 2.41 μg/ml and 3.92 μg/ml, respectively, observed at 2 h. These concentrations declined in parallel with serum concentrations and were not measurable at 48 h. Urine gentamicin concentration was relatively high, with a mean peak concentration of 424.9 μg/ml at 1 h after drug administration.  相似文献   
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