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区内出露基岩主要为黑云角闪斜长片麻岩，少量斜长角闪岩和磁铁石英岩，根据本次采集的岩矿物性标本测试成果结合区域岩石磁性统计结果黑云角闪斜长片麻岩和斜长角闪岩属微磁或弱磁性岩石，磁铁石英岩具有较高的磁性，与围岩磁性差异明显，采用磁测方法在本区寻找铁矿效果较好。 相似文献
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1区域地质本地区处中朝准地台褶皱带辽西台陷,北镇凸起东端,地层以太古界中元古界地层为主,构造以单斜构造为主;区域岩浆活动频繁,岩浆岩以中生代岩浆岩为主。1.1地层区内地层有太古界地层、中元古界长城系地层。按由老到新顺序,叙述如下:太古界地层:区域太古界地层以白厂门片麻岩(原建平群变质岩系)单位为主(Ar3Bng)。分布在少木土沟-三道沟-大岭一带及国华乡周边一带。总体呈北东向展布,岩性以黑云斜长片麻岩、角闪斜长片麻 相似文献
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通过对贝勒库都克一带花岗岩类的岩相学、岩石化学特征的详细研究,结合最新的大地构造学和地球化学研究资料,贝勒库都克序列中主要岩性有细中粒不等粒正长花岗岩,似斑状中粒含黑云正长花岗岩,似斑状中粒含黑云二长花岗岩,细粒正长花岗岩,似斑状细粒二长花岗岩。岩石化学总体上具有高硅、高铝、贫钙镁.贝勒库都克岩体明显富集Rb,Th,Ce,亏损Ba,Ta,Zr,Eu等元素。稀土元素含量较高,稀土元素配分模式呈较平坦的"V"字型体,地球化学以铕强亏损为特征;贝勒库都克花岗岩形成在碰撞,造山之后,相对稳定的环境。 相似文献
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试验以3.5~4岁成年青海高原牦牛、雪多牦牛、环湖牦牛公牛为研究对象,通过测量牦牛体重以及体高、体斜长、胸围等体尺性状,并对各性状相关性进行了统计分析,探究了与成年公牦牛体重密切相关的体尺性状,建立了体重与体斜长、胸围的最优线性回归模型。结果表明:影响成年青海公牦牛体重的主要体尺性状为胸围和体斜长,并且其体重与体斜长、胸围呈显著线性关系。该结论可用于实际生产中成年青海公牦牛体重的估算。 相似文献
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以会理青皮软籽石榴为试验材料,研究石榴不同枝梢完全花比例及坐果率。结果表明：①不同枝梢完全花占开花量的比例：极短枝（33.49%）＞短枝(21.51%)＞中枝(8.81%)＞长枝(7.32%);②不同枝梢坐果率：极短枝(6.60%）＞短枝(5.28%）＞中枝(1.55%）＞长枝(0.24%）。结论：①极短枝、短枝是石榴坐果的关键枝;②石榴头茬花的完全花比例高、坐果率高。 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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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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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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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 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
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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