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In 1977, heating, cooling, lighting, and other operations in residential and commercial buildings used 27 quads (1 quad = 10(15) British thermal units) of energy. This is more than one-third of the nation's total energy budget. Future trends in energy use in buildings are likely to depend strongly on fuel prices and government policies designed to save energy. Three scenarios are examined: (i) a base line in which fuel prices rise as projected by the Department of Energy; (ii) a conservation case that includes higher gas and oil prices plus the regulatory, financial incentive, and information programs authorized by the 94th Congress and proposed in the April 1977 National Energy Plan; and (iii) another conservation case that also includes new technologies (more efficient equipment, appliances, and structures). These scenarios are analyzed for changes in energy use, costs, and employment by means of detailed engineering-economic models of energy use in residential and commercial buildings developed at the Oak Ridge National Laboratory and input-output analyses developed at the University of Illinois.  相似文献   
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AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

4.
Suspected adverse reactions (SARs) reported for Cartrophen Vet (100 mg sodium pentosan polysulphate/ml) to the Veterinary Medicines Directorate in the UK for the period January 1991 to October 1999 were reviewed. Of the 161 reports, 28 were probably product related, 54 were possibly product related, 71 were unlikely to be related and eight were unclassified. An estimated real incidence of adverse reactions probably and possibly associated with Cartrophen Vet of 0.074 per cent on an individual dose basis was calculated (assuming only 10 per cent were documented due to underreporting). Sixty-two SARs (38.5 per cent) documented emesis, 22 (35.5 per cent) of which were product related (onset five to 15 minutes after administration). Sixty-eight SARs (42.2 per cent) documented general changes to demeanour, 10 (14.7 per cent) were product related (lethargy and/or mild depression and/or mild inappetence lasting up to two days after administration). Six SARs were considered likely to be associated with concurrently administered carprofen. Cartrophen Vet had a low incidence of side effects that were mild and transitory.  相似文献   
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By virtue of their accumulated genetic alterations, tumor cells may acquire vulnerabilities that create opportunities for therapeutic intervention. We have devised a massively parallel strategy for screening short hairpin RNA (shRNA) collections for stable loss-of-function phenotypes. We assayed from 6000 to 20,000 shRNAs simultaneously to identify genes important for the proliferation and survival of five cell lines derived from human mammary tissue. Lethal shRNAs common to these cell lines targeted many known cell-cycle regulatory networks. Cell line-specific sensitivities to suppression of protein complexes and biological pathways also emerged, and these could be validated by RNA interference (RNAi) and pharmacologically. These studies establish a practical platform for genome-scale screening of complex phenotypes in mammalian cells and demonstrate that RNAi can be used to expose genotype-specific sensitivities.  相似文献   
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A MicroRNA feedback circuit in midbrain dopamine neurons   总被引:4,自引:0,他引:4  
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Akabane disease in sheep   总被引:1,自引:0,他引:1  
Perinatal lamb mortality, associated with malformations of the CNS due to Akabane viral infection, occurred in 4 of 9 flocks of ewes lambing on 3 farms between 26 May and 14 November, 1976. Cases were restricted to ewes conceiving prior to the second week of March and lambing between 26 May and 19 July. As judged by seroconversion in sentinel flocks on 2 of the farms, field infection with Akabane virus occurred mainly between mid-February and mid-April. Malformations of the CNS occurred in 42.5%, 51.2%, 100% and 31.0% of the dead lambs examined in the affected flocks respectively. Prevalence in the 4 affected flocks, expressed as the proportion of ewes lambing which delivered at least one malformed foetus, was 6.1%, 8.4%, 88.9% and 5.7% respectively. Lamb mortality due to malformations of the CNS was 7.1%, 5.5%, 92.3% and 5.7% of lambs born. Age-specific prevalence was calculated for 3 of the 4 flocks and 2-year-old ewes accounted for 71.4% and 76.9% of total cases respectively in 2 flocks, whereas in one flock malformations occurred at equivalent frequencies throughout several older age groups. Birthweights of affected lambs were usually significantly lighter than those of unaffected lambs of similar sex and birth-type, and their mean duration of gestation was slightly, and significantly, prolonged. Micrencephaly (88.1% of cases) and hydrocephalus (68.7% of cases) were the outstanding pathological features of the malformations with hydranencephaly, microgyria, porencephaly and attenuation of the spinal cord occurring at much lower frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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