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为探讨白术和白头翁水煎液对鸡离体空肠运动张力的影响,采用离体器官试验法,以鸡的空肠平滑肌张力变化为指标,将鸡的离体空肠置于恒温通气台式液中,分别加入浓度为4.00g/L、8.00g/L和16.00g/L的白术和白头翁的水煎液,以观察白术和白头翁对不同肠管运动张力的影响。试验结果表明,白术水煎液能促进鸡离体空肠平滑肌收缩运动,使收缩张力和舒张张力增强,收缩振幅增大,其剂量越大作用越强,并呈量效关系。白头翁水煎液极显著抑制鸡离体空肠平滑肌的自律性收缩活动,可降低空肠运动张力,减小收缩幅度,加大剂量其抑制效果亦随之加强。 相似文献
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为了观察不同浓度的马钱子水煎液对家兔离体小肠运动性能的影响,笔者采用离体器官试验法,将家兔离体肠管置于恒温(38±0.5℃)平滑肌槽中,向平滑肌槽中加入浓度为5 g/L、10 g/L、15 g/L、20 g/L和25 g/L马钱子水煎液,记录给药前后十二指肠、空肠平滑肌运动性能的变化。结果表明,与用药前比较,5 g/L、10 g/L浓度时能促进十二指肠运动性能,15 g/L、20 g/L和25 g/L浓度时抑制十二指肠运动性能;在10 g/L浓度的时促进空肠运动性能;25 g/L时抑制空肠运动性能。说明马钱子水煎液对离体十二指肠和空肠收缩张力,收缩振幅和收缩频率的作用表现为低浓度兴奋、高浓度抑制。 相似文献
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《当代畜牧》2016,(27)
为了观察不同浓度槐花水煎液对家兔离体小肠运动性能的影响,笔者采用离体器官实验法,将兔离体肠管放置于恒温(38.0±0.5℃)平滑肌槽中,依次加入0.2 g/L、0.4 g/L、0.6 g/L、0.8 g/L浓度的槐花水煎液,记录给药前后十二指肠、空肠平滑肌运动性能的变化。结果表明,与用药前比较,水煎液浓度为0.2 g/L时,离体十二指肠的收缩张力明显下降(P0.01),收缩振幅、收缩频率无显著变化(P0.05);离体空肠的收缩张力、收缩振幅明显下降(P0.01),收缩频率不显著(P0.05)。随着浓度增加到0.4 g/L、0.6 g/L、0.8 g/L时,离体十二指肠和空肠的收缩张力、收缩振幅、收缩频率极显著下降(P0.01)。说明槐花水煎液能显著降低离体十二指肠和空肠的收缩张力、收缩振幅和收缩频率,且呈现量效关系。 相似文献
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通过通肠散对小鼠小肠推进率的影响及对兔离体空肠作用的研究,观察通肠散的泻下作用,并探讨通肠散的泻下作用机理。取通肠散和墨汁的混合物及生理盐水和墨汁的混合物,小鼠灌胃,取小肠测定其推进率;取兔离体空肠,分别加入通肠散0.02mL、0.04mL、0.06mL、0.08mL,以给药前为空白对照,观察对兔离体空肠的作用;取兔离体空肠,分别加入通肠散、硫酸阿托品、肾上腺素、硝苯地平0.02mL,分别观察对通肠散至兔离体空肠兴奋作用的影响。试验组小鼠灌胃后,提高了小鼠小肠的推进率,与对照组相比差异极显著(p＜0.01);通肠散各剂量组对兔离体空肠的最大张力、最小张力、平均张力、收缩频率均有显著提高,与对照组相比差异极显著(p＜0.01),且存在量效关系;硫酸阿托品、肾上腺素可拮抗通肠散对兔离体空肠的兴奋作用,硝苯地平对通肠散对兔离体小肠的兴奋作用无显著影响。通肠散可以提高小鼠小肠的推进率,对兔离体空肠具有兴奋作用,且该兴奋作用可被硫酸阿托品、肾上腺素所拮抗。 相似文献
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《广西蚕业》2018,(4)
添食氟苯尼考可以有效预防和治疗大部分家蚕细菌病。本试验探讨体喷不同浓度的氟苯尼考溶液对大蚕的安全性,探索喷施方法及最佳使用浓度。采用5龄第3 d喷施不同浓度的氟苯尼考1次,调查对家蚕食桑量、体质、上蔟、发病率、蚕茧质量等方面的影响。试验结果表明:家蚕5龄第3 d体喷0.84 mg/mL浓度氟苯尼考溶液处理的蚕儿食桑量较多,产量较高,上蔟相对整齐,且对蚕体质、茧质无影响。而1.68 mg/mL、3.36 mg/mL两个浓度处理下的产量与0.84 mg/mL浓度在产量上相似,但用药成本较高且上蔟整齐度差,因此,体喷氟苯尼考的最佳使用浓度为0.84 mg/mL。 相似文献
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研究了改性蒙脱石对黄曲霉毒素B1的等温吸附,以及赖氨酸、酸碱度、温度、离体肠管吸收及透析袋透析对其吸附的影响。结果表明,改性蒙脱石在pH2.0和pH8.0时对黄曲霉毒素B1的最大吸附量分别为598.8μg/g、682.4μg/g;赖氨酸含量为2.0mg/mL和4.0mg/mL时对吸附无影响;酸碱度在pH2.0至pH8.0及温度在20℃至60℃时对吸附无明显影响;改性蒙脱石可减少离体肠管对黄曲霉毒素B1的吸收率及黄曲霉毒素B1通过透析袋的透析率。改性蒙脱石对黄曲霉毒素B1可能以化学吸附为主;鸡小肠对黄曲霉毒素B1存在主动吸收过程。 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
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献