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以白刺花种子为材料,分别采用砂纸摩擦,30%NaOH浸种0.5、1、1.5、2、2.5、3h,90%NaOH浸种5、15、25、35、45、55min,98%浓硫酸浸种10、20、30、40、50min对种子进行硬实处理,在室温(25~28℃)下进行发芽试验。结果表明:砂擦处理效果最好,发芽率为80%;98%浓硫酸处理... 相似文献
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敖汉苜蓿硬实种子处理方法研究 总被引:10,自引:0,他引:10
试验以2002年收获的敖汉苜蓿种子为材料,采用不同水温浸种、98%浓硫酸不同浸种时间和石英砂磨破种皮等处理来研究打破敖汉苜蓿种子硬实的效果。结果表明,浓硫酸浸种处理中效果最佳的是浸种60 min,平均发芽率达到99%;不同水温浸种处理中效果最佳的是75℃的热水处理,平均发芽率达到79%。3种处理中以98%浓硫酸浸种60 min的效果最好,其次是石英砂磨破种皮,而各种水温浸种的效果较差。 相似文献
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不同处理方法对3种豆科灌木种子发芽率的影响 总被引:10,自引:4,他引:6
采用不同的化学试剂对多花木蓝,紫穗槐和胡枝子3种灌木的种子进行处理,测定其发芽势和发芽率。结果表明,不同处理下发芽率的差异达极显著水平(P<0.01)。其中,多花木蓝的种子,以浓硫酸浸泡15 min和100 g/L硝酸钾溶液浸泡6 h的处理最好,发芽率在72%以上;紫穗槐经浓硫酸浸泡15 min,平均发芽率在76%以上;胡枝子则以30%的双氧水浸泡30 min最好,发芽率为72.7%。因此,选用适宜的方法处理种子,可降低种子硬实率,打破休眠,从而提高种子发芽率。 相似文献
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实验设计了两种方法来提高伏生臂形草的种子发芽率,分别为:不同浓硫酸浸种时间和硝酸钾溶液培养浓度。结果表明,浓硫酸浸种19min,种子发芽率较高,达69.67%;0.3%的硝酸钾溶液培养,种子发芽效果较好,发芽率为60.67%。 相似文献
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以野外采集的獐茅(Aeluropus littoralis)种子为材料,分别以98%H2SO4浸种2、5、10、20、30和60min、0.5%、1%、5%、10%和20%NaOH浸种30 min和0.2%、0.6%、1%、2%和5%KNO3溶液浸种24 h处理后进行种子发芽试验,研究不同化学试剂对獐茅种子发芽和幼苗生长的影响。结果表明,3种化学试剂均能提高种子发芽率,促进幼苗生长,其中98%H2SO4浸种5 min、10%NaOH浸种30min以及0.2%KNO3浸种24 h处理效果较好,发芽率分别为13.3%、42.2%和20.0%,幼苗长度分别为0.79、1.97和1.13mm。10%NaOH处理方法简单易行,破除獐茅种子休眠效果最好。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献