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PGF2αeCG及hCG 3种生殖激素联用对母犬发情、卵泡发育及胚胎着床的影响 总被引:3,自引:0,他引:3
给休情期性成熟母犬肌注 PGF2α(0 .5 m g/ kg) ,2 4 h后肌注 e CG(5 0 IU/ kg) ,再经 12 0 h后肌注 h CG(2 0 U/ kg) ,诱导其发情。将诱导发情的母犬与公犬交配 ,于交配后 16 d,摘取卵巢、子宫 ,观察其卵泡发育和胚胎着床情况。结果表明 ,药物处理可明显促使母犬提前结束休情期而进入发情期 (9/ 10 ) ,促进卵巢内卵泡发育 (P<0 .0 1) ,并使更多的胚胎着床 ,每只母犬子宫胚胎着床点为 (17.4± 2 .2 )个 ,提示 3种生殖激素联合应用可提高母犬繁殖率 相似文献
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从理论上分析了错相及缺相判别原理,提出了新颖保护电路,其线路简单、实用。 相似文献
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The efficacy of mixtures of respiration inhibitors and phenylamide fungicides (oxadixyl and metalaxyl) in controlling late blight was investigated using potato tuber disks. Results showed that uncoupling agents(e.g. DNP), inhibitors of ATP formation(e.g. oligomycin), ionophores(e.g, valinomycin) and inhibitors that block specific carriers in the electron transport chain(e.g. rotenone, antimycin A) increased significantly the control efficacy of both metalaxyl and oxadixyl towards populations ofPhytophthora infestons when applied to tuber slices pretreated with sublethal doses of both fungicides. When applied alone at the same doses, respiration inhibitors did not inhibit the development of the late blight fungus. Increased control efficacy of mixtures was not noted against phenylamide-sensitive populations of the fungus. 相似文献
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Mixtures of cymoxanil with mancozeb (Mancur) or with mancozeb plus oxadixyl (Pulsan, Sandocur-M) were effective in controlling either metalaxyl-sensitive (MS) or -resistant (MR) isolates ofPseudoperonospora cubensis on cucumbers (cv. ‘Elem’) in growth chambers. Metalaxyl+mancozeb (Ridomil-MZ) and oxadixyl+mancozeb (SAN-518) mixtures were effective against the metalaxyl-sensitive but less so against the metalaxyl-resistant isolate. Fungicide mixtures were far more effective in controlling either the sensitive or the resistant isolates than were the individual components applied alone, thereby representing significant levels of synergistic interactions. Increased efficacy of mixtures relative to their combined components (synergy factor) was calculated by the Wadley method. Mixtures containing cymoxanil showed high synergy factors against the resistant isolate, whereas Ridomil-MZ and SAN-518 did not evince this phenomenon. We concluded that cymoxanil mixtures might be suitable for the control of downy mildew incited by a metalaxyl-resistant isolate ofP. cubensis. 相似文献
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Exposure of Israeli agricultural spray pilots and ground crews to parathion was studied. Measurements were made with personal samplers contianing wet midget impingers; samples were analyzed by gas chromatography. Cockpit air exposure levels during 11-21-minute sampling periods for 12 flights ranged from nearly 0 to 430 microgram/m3. During sampling periods of 30 minutes to 4 hours the threshold limit value (TLV) of 100 microgram/m3 was exceeded in 2 of 19 instances. In seven measurements of ground crew exposures, TLV was not exceeded. Air washing with parathion resulted in airborne contamination of the ground level area at more than three times the TLV. Skin exposure data suggested that this route of exposure was significant for ground crew workers but not for pilots. Calculations based on the present data and standard absorption formula suggested that total daily intake for ground crew, but not for pilots, exceeded the Accepted Daily Intake (ADI) of 5 microgram/kg body weight. Sources of exposure and contamination for ground crew and pilots were identified. Recommended environmental control measures for parathion exposure should include cockpit air filtration, modification in flight patterns, paving landing areas, installation of hosing and drainage, NaOH neutralization point, and separate loading and unloading sites. Personal control measures were suggested as a supplement. 相似文献
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A method for monitoring tobacco whitefly [Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae)] populations was developed and used for timing spray applications against this pest in cotton. It was found to be successful in tests in eight commercial cotton fields. A trap composed of a yellow plastic plate (15 × 20 cm) smeared on the upper side with a thin layer of glue, was attached to an iron pole which held the plate in a horizontal position above the plants. The traps were placed 400 m apart along the periphery of the field. The sticky plates were changed weekly and the adult whiteflies were counted. When the mean weekly catch per trap reached ~ 100–200 adults, spray applications were carried out. Following this treatment,B. tabaci populations remained low and sooty mould did not develop on the lint. 相似文献