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91.
Marshall E 《Science (New York, N.Y.)》2000,288(5472):1715b-1717b
On 31 May, the Cystic Fibrosis (CF) Foundation of Bethesda, Maryland, announced that it will invest at least $30 million in a small biotech firm, Aurora Biosciences of San Diego, to identify compounds that might prove useful in treating CF. This project, fueled initially by a donation of $20 million from the Bill and Melinda Gates Foundation, marks a new departure in the growing trend of patient groups taking charge of biomedical research. 相似文献
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Relative date of first calving of beef heifers was studied in relation to production efficiency and subsequent reproductive performance. Crossbred heifers were managed in a drylot environment for 1 yr with feed intake measured through weaning of the first calf. Mean heifer age at entry into drylot was 572 d. Production traits were evaluated by calving group (CG), where CG1 included records of heifers calving (and calves born) in the first 21 d of the calving season for a particular year, CG2 included those calving from 22 through 42 d and CG3 included those calving after 42 d. Calving groups did not differ significantly for preweaning calf ADG, but weaning age differences resulted in heavier weaning weights for CG1 compared with CG2 and CG3. An earlier relative calving date was associated with increased cumulative feed energy intake of heifers and their calves during the 1-yr test period. In terms of production efficiency, the weaning weight advantage of earlier calving was offset only partly by the increased feed energy intake of the dam-calf unit, resulting in 6.3 Mcal (12.4%) less ME per kg calf weaning weight for CG1 vs CG3 for the 1-yr period. Within a limited calving season, earlier calving dams tended to be biologically and economically more efficient because a greater proportion of their annual production cycle was in a productive (lactating) mode, diluting maintenance costs as a fraction of all costs. Heifers in CG1 also tended to calve earlier than CG3 heifers for the second calf. Calving interval was a biased measure under the management conditions of a limited breeding season and culling of open cows. 相似文献
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Experimental infection of normal and immunosuppressed pigs with Pseudomonas pseudomallei 总被引:1,自引:0,他引:1
AD THOMAS JC FORBES-FAULKNER TL D''ARCY JH NORTON D HOFFMANN 《Australian veterinary journal》1990,67(2):43-46
A single dose of 5 x 10(8) bacilli of Pseudomonas pseudomallei by intratracheal injection resulted in acute (21 cases) or chronic (19 cases) melioidosis in 40 of 48 pigs. Fifteen (10 acute and 5 chronic) had been immunosuppressed by cyclophosphamide before inoculation. The major clinical signs were initial fever, marked neutrophilia and, in the acute cases, respiratory distress. There were no signs of the nasal and ocular discharge, paresis or diarrhoea seen in acute cases in south-east Asia. The cyclophosphamide treatment caused a significant decrease in the neutrophil count by 7 d after inoculation in all 15 immunosuppressed pigs, and all were culture positive at necropsy. Eight of the 33 non-treated pigs were culture negative at necropsy. Pigs overcoming the initial phase of infection had more abscess-like nodules that were bacteriologically sterile at necropsy than the pigs with acute cases of melioidosis. P. pseudomallei was isolated predominantly from the spleen, lungs and the injection site. Although only one strain was used in this study, it is likely that Australian strains of P. pseudomallei are not as virulent as the south-east Asian isolates. 相似文献
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Abstract: Will future transportation carbon dioxide (CO2) emissions per capita in Asia Pacific economies follow historical trends of the now developed world? Evidence to date is inconclusive. A comparison at similar income levels (purchasing power parity) between recent emissions in Asia Pacific countries and historical emissions in developed countries suggests diverging patterns. (A) High‐income Asia economies (Japan, Hong Kong and Singapore –‘low emitters’) exhibit lower emissions than a selected sample of seven developed countries (United States, Australia, France, the Netherlands, Italy, Sweden and United Kingdom). (B) Another set of Asian countries (South Korea and Taiwan –‘medium emitters’) follow the emissions trends of European countries, which are lower than those of Australia and the United States. (C) A third Asian group (Malaysia and Thailand –‘high emitters’) exhibit emission trends comparable to that of Australia. We describe these trends, examine their causes and extrapolate likely futures for emissions in low‐income Asia Pacific economies (China, Indonesia, Philippines and Vietnam). Although such predictions are speculative, the available evidence suggests that road CO2 emissions for Indonesia, the Philippines and Vietnam will follow those of the third group (high emitters), while those for China may follow either Group B or Group C. 相似文献