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91.
阿克苏地区2000-2001年从山东省农科院引进强筋面包小麦新品种济南17号,在地区农业试验站进行品种区域适应性比较试验,并对其生育和植株性状进行了观测,在参试的8个品种中,济南17号平均产量6804kg/hm2,位居第三,较对照邯5316(地区小麦主栽品种)增产840kg/hm2,增产率14%。2001-2002年又在地区农业试验站对该品种示范种植800.04m2,产量8550kg/hm2,首次实现本地区引种面包小麦单产超8250kg/hm2的产量水平,两年试验示范结果表明,该品种在阿克苏地区具有较强的适应性和丰产性,同时取得了实现强筋小麦济南17号高产栽培的实践经验。  相似文献   
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Objective: To determine the efficacy of a novel copper based footbath preparation (CHF-1020) for treatment of ovine footrot during the spread period.
Design: A series of field trials with treated and control groups run together.
Animals: Mobs of at least 125 sheep on each of six properties in southern New South Wales with equal numbers of controls.
Procedure: Sheep of group A were treated after minimal paring by making them stand in CHF-1020 for 15 minutes. Treatment was undertaken at intervals throughout the period of the trials (14 September to 17 December 1993). Group A sheep were run on the same pasture as those from group B (untreated sheep).
Results: The percentage of sheep exhibiting clinical signs of ovine footrot at the start of the trial ranged from 35 to 88% at score 3 or higher, using a 0 to 5 footscoring system. During the trial, the percentage of infected sheep (greater or equal to score 2) in group B increased and ranged from 40 to 90%. The level of infected sheep in group A on each property was reduced progressively to 1 to 16%. Cure rates of 45 to 94% were achieved, with the lowest rate being on a property with a metal footbath. The next lowest cure rate was 73%. Results indicated that treatment should be undertaken at 2-weekly intervals while spread continues. Treated sheep can be returned to contaminated pastures.
Conclusion: CHF-1020 is effective during the spread period and can be used for the progressive eradication of ovine footrot.  相似文献   
94.
从音乐本身出发,从琵琶音乐语言和琵琶音乐表达的技术手段两方面对琵琶音乐语言的表现力作出作者自身的理解.琵琶音乐语言的表现力是多元性的,可以从琵琶音乐语言特性的界定以及琵琶音乐表达的技术手段来了解.  相似文献   
95.
A survey of 73 dairy farms in south-western Victoria was conducted to assess the cost and mean herd incidence of foot lameness for the period from calving to the end of November, 1985, and to identify the herd, management and environmental factors associated with foot lameness. The mean herd size was 125 cows (range 82 to 220). Lameness occurred in 64 (88%) herds, and the mean herd incidence was 7.0% (range 0.0 to 30.9%). The main clinical signs associated with lameness were the presence of overworn and/or bruised soles, or stones lodged in the interdigital cleft. Factors associated with lameness were: property and herd size, age of cow, bail feeding, voluntary entry into the bails, and features of the farm track including its length, the presence of steep slopes, the type of surface material, presence and treatment of broken sections and maintenance including rolling history. The association of these factors with specific clinical signs was examined. The mean cost was estimated to be $42.90 per lame cow due to loss of production, treatment, the culling or death of lame cows, and extra man hours spent managing lame cows. It was concluded that the site, construction, maintenance and use of the farm track were of major importance to the incidence of lameness in herds in this area and recommendations for reducing lameness are made.  相似文献   
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Four strategies for selecting cows for intramammary therapy with benzathine cloxacillin at drying off were compared in 12 Victorian dairy herds. The bacteriological status of all quarters of all (1044) cows was determined just before drying off, within 2 d of calving, and again 3 to 5 months after calving. All cases of clinical mastitis (from calving to mid-lactation) were recorded. Cows not infected at drying off were allocated randomly to 2 subgroups of approximately 350 cows each: not infected, not treated (NI-NT), or not infected, all quarters treated (NI-AT). New infection rates in the dry period (3.8% for NI-NT vs 2.1% for NI-AT) and in early lactation (4.1% for NI-NT vs 3.9% for NI-AT) were low and these differences were not significant. Incidence of clinical mastitis in early lactation was almost 50% higher for the treated group of uninfected cows compared with the untreated group (0.05 less than p less than 0.1). Cows infected in one or more quarters at drying off were split randomly into 2 subgroups of approximately 170 cows each: infected, all quarters treated (I-AT), or infected quarters treated only (I-QT). The new infection rate during the dry period was nearly 4 times higher for I-QT (15.3%) due to significantly more new infections by Staphylococcus aureus and Streptococcus uberis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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High angular resolution images of extragalactic radio sources are being made with the Highly Advanced Laboratory for Communications and Astronomy (HALCA) satellite and ground-based radio telescopes as part of the Very Long Baseline Interferometry (VLBI) Space Observatory Programme (VSOP). VSOP observations at 1.6 and 5 gigahertz of the milli-arc-second-scale structure of radio quasars enable the quasar core size and the corresponding brightness temperature to be determined, and they enable the motions of jet components that are close to the core to be studied. Here, VSOP images of the gamma-ray source 1156+295, the quasar 1548+056, the ultraluminous quasar 0014+813, and the superluminal quasar 0212+735 are presented and discussed.  相似文献   
100.
H2O2能氧化修饰离体小麦叶片蛋白质分子中的-SH基团,使蛋白质分子更容易被蛋白水解酶降解,表现为蛋白水解酶活力升高,蛋白质含量下降加快。随着H2O2浓度的增大,这一现象更加明显。  相似文献   
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