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71.
The thermostability of a rinderpest vaccine produced on Vero cells was evaluated using a variety of chemical stabilizers and lyophilization protocols. Three stabilizer preparations and three lyophilization schedules were examined using accelerated stability testing at 37 degrees C. The vaccine preparation exhibiting the greatest stability at 37 degrees C was tested at three additional temperatures, 42, 45 and 56 degrees C, and an Arrhenius plot was constructed from the data. The stability of the reconstituted vaccine produced with the two most efficacious stabilizers was examined using three different diluent preparations. The stabilization method and high Vero cell virus batch titers resulted in a lyophilized vaccine which maintained the minimum required dose of log10 2.5 TCID50 tissue culture infectious dose for more than 20 weeks at 37 degrees C.  相似文献   
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Clifford R.  Berry  DVM  John K.  House  DVM  Paul P.  Poulos  DVM  PhD  John E.  Madigan  DVM  MS  J. Carroll  Woodard  DVM  PhD  Roy R.  Pool  DVM  PhD  Timothy R.  O'Brien  DVM  PhD  Norman  Ackerman  DVM 《Veterinary radiology & ultrasound》1994,35(5):355-361
The radiographic and pathologic findings of two Peruvian Paso foals with osteopetrosis are described. Both foals, one male and one female, presented with respiratory difficulty, brachygnathia and failure to rise after birth. Both foals were mildly anemic, hypogammaglobulinemic and had elevations in serum alkaline phosphatase. Increased medullary bone opacity was noted on radiographs of the extremities, spine and skull in both foals. A lack of normal cortical:medullary bone distinction was evident radiographically. The medullary primary spongiosa appeared to run in parallel columns away from the physes of all long bones and the vertebrae. This created a distinctive hour glass appearance to the osteopetrotic bones. One foal developed a bacterial pneumonia. Both foals were euthanized due to failure to thrive. Histopathology and electron microscopy documented these foals to have normal osteoclastic numbers but lack normal ruffled borders, lack of a clear zone and normal lysosomal numbers indicative of cellular dysfunction. These clinical, radiographic and pathologic findings are similar to the juvenile, lethal autosomal recessive form of osteopetrosis described in humans. Osteopetrosis has not been previously described in a female foal.  相似文献   
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The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter.  相似文献   
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Objectives To document the equine perioperative mortality rate and to highlight any factor associated with an increased risk of death up to 7 days after anaesthesia. Study design A prospective observational epidemiological multicentre study. Methods Data were recorded from all equidae undergoing general anaesthesia in 62 clinics. Power calculations indicated that 45 000 cases were required to detect the significance of important variables. Details of each horse, operation, anaesthetic agents and clinic personnel were recorded. Outcome at 7 days was recorded as: alive, put to sleep (PTS) or dead. Data were analysed by a standard multilevel logistic regression approach, considering the effects of clustering at the level of clinic. Results Data were collected from 41 824 cases over 6 years. A total of 39 025 (93.3%) were alive on day 7 and 785 were dead giving an overall death rate of 1.9% (95% CI: 1.8–2.0) and 2014 (4.8%) were PTS. About 5846 horses undergoing emergency abdominal surgeries (‘colics’) were excluded from subsequent analyses. A total of 35 107 ‘noncolic’ horses were alive at 7 days and 328 dead giving a death rate for noncolics of 0.9% (95% CI: 0.8–1.0). Five hundred and forty‐three (1.5%) noncolic horses classified PTS were excluded from further analyses. There were 109 (33%) deaths from cardiac arrest or post‐operative cardiovascular collapse, with 107 (32%) from fractures and myopathies. Fracture repair, out of hours surgery, and age below 1 month was associated with increased risk of dying whereas the use of acepromazine and intravenous anaesthetic agent maintenance of anaesthesia was associated with reduced risk. Conclusions A number of potential contributors to the high risk of anaesthetic‐related mortality have been identified. Further investigation of the underlying mechanism for their apparent harmful effects and development of alternative techniques is merited.  相似文献   
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