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1.
Plasma triglyceride concentrations were measured in sheep given Intralipid or propofol, which is carried in a vehicle very similar to 10% Intralipid. A bolus dose was administered followed immediately by an infusion of the same agent for 2 h. In the animals that received propofol, the measured concentration increased by a mean amount of 3.39 mmol/l when the infusion rate was l ml/min (Group Pl) and by 7.13 mmol/l when it was 2 ml/min (Group P2). When 10% Intralipid was administered and infused at 1 ml/min (Group I10), the measured concentration increased only by 0.95 mmol/l. One hour after stopping the infusion, the excess of measured concentration over baseline had decreased in the Pl and I 10 groups to 0.52 and 0.13, respectively, of the corresponding maximum excess. The method adopted for measuring plasma triglycerides is widely used in hospitals; however, an incidental observation revealed that it is inappropriate in the presence of injections of propofol or Intralipid. Despite this, evidence and argument are presented to support the conclusion that, with propofol, plasma triglyceride concentrations increased more rapidly during the infusions and returned to baseline more slowly than with a corresponding amount of Intralipid.  相似文献   
2.
The objective of the present study was to examine the interaction between graded levels of leucine and dietary crude protein. Dose–response curves were generated using four 3 × 3 Latin squares (two dogs/square). Each square represented one of two concentrations of crude protein (140 or 280 g/kg diet) and one of two combinations of three concentrations of leucine (5.0, 7.0 and 9.0 g/kg diet or 9.0, 11 and 13 g/kg diet). An additional experiment was performed by feeding crude protein at 210 g/kg diet with either 7.0 or 11 g leucine/kg diet. Weight gain, food intake, nitrogen retention, plasma albumin and plasma amino acids were measured. The requirement was determined to be the minimum leucine concentration required to maximize weight gain and nitrogen retention. For 8–14-week-old male Beagle dogs, 140 g crude protein/kg diet in a diet containing 18 kJ metabolizable energy/g does not appear to support maximal growth. The leucine requirement was not affected by doubling the dietary crude protein level from 140 to 280 g/kg diet. From these results, the leucine requirement of 8–14-week-old Beagle dogs appears to be 11 g leucine/kg diet independent of the level of dietary crude protein, whereas dogs over 14 weeks require only 7 g leucine/kg diet for maximal nitrogen retention.  相似文献   
3.
Bovine semen samples spiked with bovine herpesvirus 1 (BHV-1) were used to compare dot blot hybridization, polymerase chain reaction (PCR), and virus isolation for detection of BHV-1 in bovine semen. The PCR amplification used primers targeting the BHV-1 thymidine kinase gene and a nucleic acid releasing cocktail (GeneReleaser); the PCR product was used as the DNA probe in dot blot hybridization; virus isolation was done in primary bovine fetal testis (BFT) cell cultures. Semen diluted 1:20 in tissue culture medium had the least cytotoxicity and inhibition of viral cytopathic effects in BFT cells, allowing detection of 1 TCID50/100 microL of BHV-1 suspension by virus isolation. The presence of foreign DNA such as bovine sperm DNA or salmon sperm DNA increased the sensitivity of dot blot hybridization in detecting BHV-1, allowing detection of 20,000 TCID50/100 microL of neat semen. The inhibition of PCR amplification of BHV-1 DNA in bovine semen was eliminated by diluting the samples 1:20 in tissue culture medium. The best PCR amplification was obtained when semen was diluted 1:20 and when a reaction buffer of pH 9.0, with 1.0 mM MgCl2 was used. Under these conditions, the PCR followed by ethidium bromide staining of agarose gels could detect 1 TCID20/100 microL of sample, whereas PCR followed by Southern blot hybridization could detect 0.01 TCID50/100 microL of sample.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Intranuclear cisternal and vesicular structures, bound by a single membrane, were observed for the first time in some glandular "bird's eye" cells of canine circummanal gland carcinomas. The role of these intranuclear structures is not clear. It is suggested that they may be involved in cellular adaptation to an environment of nutrient deficiency, as a result of cell overcrowding.  相似文献   
5.
Bluegill absorbed 85% of 1 ppb of endrin from water within 48 hr under static exposure conditions. The absorbed radiocarbon was eliminated linearly with a half-life of about 4 weeks. Analyses of eliminated radioactivity revealed only conjugated metabolites. 12-anti-Hydroxyendrin and 12-syn-hydroxyendrin were tentatively identified by cochromatography using thin-layer chromatography/autoradiography and gas chromatography. These metabolites were also present as conjugates in the fish organs. Seventy-three percent of the absorbed radioactivity recovered from fish extracts was in the form of unchanged endrin.  相似文献   
6.
胡桃长足象是核桃果实的大害虫,为害损失很大。1975年以来,我们在四川平武地区进行了生活习性观察和防治试验,初步明确了以下几个问题。1.胡桃长足象一年一代。11月份以成虫越冬,次年4月上旬开始活动,为害果、芽、嫩枝、叶柄,5月上旬交尾产卵于果中,一般一果一粒,8月中旬产卵结束,10月陆续死亡。当年成虫6月中旬羽化,进行为害。2.成虫有假死性和向阳性,飞翔力弱,具有与核桃树芽苞相似的保护色。3.防治胡桃长足象,应抓住越冬成虫大量出现和卵孵化盛期时进行。用每毫升含孢量二至五亿的白僵菌液或50%的三硫磷乳油、50%速灭松乳剂、82%磷胺乳剂加水一千倍喷雾,效果良好。  相似文献   
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Several strains of Drosophila melanogaster possess mutant alleles in nicotinic acetylcholine receptor (nAChR) subunits, Dα1 and Dβ2 that confer resistance to neonicotinoids such as imidacloprid and nitenpyram, and Dα6, that confers resistance to spinosyns. These mutant strains were bioassayed with a selected set of nAChR active insecticides including neonicotinoids, spinosad, and sulfoxaflor, a new sulfoximine insecticide. All of the neonicotinoids examined, except dinotefuran showed reduced insecticidal efficacy on larvae of the Dα1 mutant, suggesting that this subunit may be important in the action of these insecticides. All of the neonicotinoids, including dinotefuran, showed reduced insecticidal efficacy on larvae possessing the Dβ2 mutation. A similar pattern of broad neonicotinoid resistance to that of Dβ2 alone was also observed for larvae with both the mutations (Dα1 + Dβ2). The Dβ2 mutation exhibited a lower level of cross-resistance to sulfoxaflor (<3-fold) than to any of the neonicotinoids (>13-fold). In contrast, there was no cross-resistance for any of the neonicotinoids or sulfoxaflor in adult flies with the Dα6 mutation, which confers high levels of resistance to spinosad. Thus in the D. melanogaster strains studied, target site resistance observed for the neonicotinoids and the spinosyns does not translate directly to resistance towards sulfoxaflor.  相似文献   
10.
Indoor and field experiments were conducted to evaluate the efficacy of applying the mycoparasite Coniothyrium minitans to the aerial parts of rapeseed plants at the flowering stage to control sclerotinia diseases caused by Sclerotinia sclerotiorum. Under controlled conditions, a petal inoculation technique was used to determine the effect of conidial suspensions of C. minitans on suppression of sclerotinia leaf blight. Results showed that C. minitans was effective in inhibiting infection initiated by ascospores of S. sclerotiorum on flower petals by restricting mycelial growth of the pathogen. Suppression of lesion development was related to the conidial concentration of C. minitans, with larger lesions at low concentration (5×103conidia ml−1), but smaller lesions at high concentration (5×104 conidia ml−1 or higher). When C. minitans-treated rapeseed leaves were inoculated with mycelia of S. sclerotiorum, C. minitans failed to prevent infection of leaves, but caused a significant reduction in number of sclerotia produced on the diseased leaves. No significant difference in efficacy was detected between the two isolates of C. minitans, LRC 2137 and Chy-1, on the two rapeseed cultivars, Westar (spring type) and Zhongyou 821 (winter type). Results of field trials showed a significant reduction of stem rot of rapeseed in four (1997, 1999, 2003 and 2004) out of five years by aerial application of C. minitans, compared with controls. No significant difference in suppressive efficacy was observed between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + benomyl (50 μg ml−1) and benomyl (100 μg ml−1) in 2003, and between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + vinclozolin (100 μg ml−1) and vinclozolin (500 μg ml−1) in 2004. Sclerotia of S. sclerotiorum collected from diseased plants in plots treated with C. minitans in 1999, 2000 and 2003, or with C. minitans + benomyl in 2003 were infected by C. minitans at frequencies ranging from 21.3 to 54.5%. This study concludes that aerial spraying of C. minitans is an effective method for controlling sclerotinia diseases of rapeseed.  相似文献   
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