共查询到20条相似文献，搜索用时 62 毫秒
1.
2.
采用原生质体融合技术,以红发夫酵母突变株和黏红酵母突变株为亲本菌株,以原生质体形成率和再生率的乘积为检测指标,对菌株菌龄、酶解温度、酶解时间和渗透压稳定剂等原生质体形成和再生的条件进行研究。结果表明,处于对数生长前期的红发夫酵母和处于对数生长中期的黏红酵母原生质体形成率和再生率的乘积显著高于其他组(P<0.05);红发夫酵母原生质体形成率和再生率的乘积在酶解温度22 ℃时为17.34%,在25和28 ℃时为0,黏红酵母形成率和再生率的乘积在22和25 ℃时显著高于28 ℃(P<0.05),但2个温度之间差异不显著(P>0.05);2菌株原生质体形成率和再生率的乘积在酶解时间为2 h时显著高于其他组(P<0.05);对照组渗透压稳定剂的组合对原生质体形成率和再生率的乘积显著高于其他组(P<0.05)。红发夫酵母和黏红酵母原生质体形成和再生的最适条件为:红发夫酵母菌龄为14 h、黏红酵母菌龄为18 h、酶解温度均为22 ℃、酶解时间均为2 h,原生质体形成的最适渗透压稳定剂均为1.0 mol/L的KCl缓冲液,再生的最适渗透压稳定剂均为17%蔗糖稀释液;最后筛选出1株能在28 ℃生长良好且虾青素含量586.38 μg/g的融合子,比融合前红发夫酵母和黏红酵母分别提高了79.58%和64.08%,且传代多次生产性能稳定。 相似文献
3.
蛹虫草具有与冬虫夏草极相似的药理作用,可作为冬虫夏草代替品.本试验以蛹虫草菌株CM-1为出发菌株,结果表明蛹虫草菌原生质体制备的快速简便方法为:菌体液体培养96h,用0.6 mol/L甘露醇溶液作为渗透压稳定剂,取1g菌丝体以1∶20比例加入复合酶液,在pH6.8、28℃条件下酶解2.5h,获得原生质体数最多,达到5.08 × 108个/mL;原生质体再生培养基为含0.6 mol/L甘露醇PDA培养基,原生质体再生率最高为4.69％. 相似文献
4.
5.
以产苦马豆素内生真菌Undifilum oxytropis NX-FEL001为供试菌株,研究了培养方式、菌龄、酶解时间和酶解温度等,对U.oxytropis原生质体制备和再生的影响。结果表明,U.oxytropis菌丝在质量分数为10g/L纤维素酶+10g/L蜗牛酶+1g/L溶壁酶组成的复合酶溶液,35℃恒温,80r/min振荡孵育3h左右,原生质体释放量最高;原生质体在YCM培养基上,22℃培养9d可以再生形成菌落,培养15d其再生率可达8.5%;原生质体在YCM培养基上再生后其菌落颜色与野生型U.oxytropis不一致,呈现白色;菌丝形态与野生型U.oxytropis相一致,经检测再生后菌丝仍然能够产生苦马豆素。U.oxytropis原生质体的制备,将为进行疯草内生真菌的遗传转化和基因操作研究提供重要工具,为进一步开展疯草内生真菌合成苦马豆素的分子调控机制奠定了基础。 相似文献
6.
建立高效的原生质体再生体系是通过原生质体融合技术培育草地早熟禾(Poa pratensis)新品种的重要前提。以甘肃陇西野生草地早熟禾(LX)和定西野生草地早熟禾(DX)胚性愈伤组织为材料,探索其原生质体游离和培养条件。结果表明,LX和DX原生质体分离的最佳酶液组合为1.5%纤维素酶R-10+0.5%果胶酶Y-23+1.0%离析酶R-10+0.3%崩溃酶;酶解时间为16 h;LX原生质体最适宜的甘露醇浓度为0.6 mol·L-1,而DX原生质体的最适甘露醇浓度为0.5 mol·L-1。LX原生质体的产量最高可达6.59×106个·g-1,DX可达5.95×106个·g-1。DX原生质体培养的最适密度为3.0×105个·m L-1,最适2,4-D浓度为1.0 mg·L-1,此时,DX原生质体再生细胞的分裂频率可达9.56%,植板率为4.62%。 相似文献
7.
苜蓿愈伤组织原生质体游离与培养 总被引：7，自引：3，他引：4
对阿尔冈金苜蓿(Medicago sativa L. cv. Algonguin)原生质体游离和培养的最佳条件进行研究,建立其细胞融合原生质体杂交体系。以下胚轴诱导的愈伤组织为材料,研究了愈伤组织继代培养时间、酶液组合、酶解时间及酶液渗透压对原生质体游离的影响,并探讨了愈伤组织原生质体在KM8P培养基上的分裂情况。结果表明:继代12d的愈伤组织游离性最好,最佳酶液组合为2%纤维素酶+0.5%果胶+1%半纤维素酶、最佳酶解时间为12h、最佳酶液渗透压为0.55mol/L;最适宜培养苜蓿愈伤组织原生质体的培养基为KM8P+2.0mg/L2,4-D+1.0mg/LNAA。 相似文献
8.
草地早熟禾午夜Ⅱ号原生质体培养及植株再生 总被引：5，自引：1，他引：4
对草地早熟禾(Poa Pratensis L.)品种-午夜Ⅱ号进行了原生质体培养及其植株再生的研究。以午夜Ⅱ号成熟种子诱导的松软胚性愈伤组织为材料,利用酶解法分离出大量有活力的原生质体。原生质体经培养,持续分裂形成愈伤组织,并分化出再生绿苗和白化苗。研究了不同酶液组成和酶解时间对原生质体游离的影响。结果表明:采用继代培养8-10 d的胚性愈伤组织在1.0%纤维素酶+1.0%离析酶+0.5%果胶酶+0.3%崩溃酶条件下,酶解14-16 h可得到产量和活力较高的原生质体。原生质体以2.0×105-5.0×105个/mL的植板密度,采用液体浅层法在附加1.0 mg/L 2,4-D、0.3 mg/L 6-BA、100 mg/L水解酪蛋白、100 mg/L水解乳蛋白、1.0%蔗糖、0.4 mol/L甘露醇的KM8P培养基中培养,可形成较小的愈伤组织。愈伤组织经过增殖在分化培养基上(MS+0.5mg/LNAA+2.0 mg/L 6-BA)可诱导芽、根的形成,再生出完整植株。 相似文献
9.
以餐厨垃圾为发酵培养基对9株酵母进行筛选,获得1株非蛋白氮转化率较高的菌株产朊假丝酵母0233,在餐厨垃圾固体培养基中发酵24h后,非蛋白氮转化率为36.69%。对该菌株的原生质体形成与再生的条件进行研究,结果表明:原生质体形成与再生最佳条件为菌龄26h,渗稳剂为含0.1%β-巯基乙醇的0.7mmol/L山梨醇,蜗牛酶浓度2.5%,酶解70min。在此条件下,原生质体形成率为92.80%,原生质体再生率为10.6%。采用He-Ne激光(632.8nm)对产朊假丝酵母0233的原生质体进行反复诱变,得到1株在餐厨垃圾固体培养基发酵后非蛋白氮转化率有较大提高的突变株,其非蛋白氮转化率为56.69%,比出发菌株(产朊假丝酵母0233)的非蛋白氮转化率提高1.6倍。该突变株经多次传代后有较高稳定遗传性,无明显的回复突变。 相似文献
10.
扁蓿豆愈伤组织原生质体分离条件的研究 总被引：5，自引：1，他引：4
以扁蓿豆(Melilotoides ruthenica(L.)Sojak)下胚轴愈伤组织为材料,研究酶液组合、酶解时间、酶液渗透压、继代培养时间及预处理措施对其原生质体分离效果的影响,以期确定能够酶解出高数量且高活力的原生质体的酶解条件。结果表明:获得有活力原生质体的最佳酶液组合为2%纤维素酶+0.5%果胶酶+0.3%半纤维素酶、酶解时间为12 h、酶液渗透压即甘露醇浓度为0.55 mol·L-1,愈伤培养天数为10~12 d、预处理措施为黑暗24 h。 相似文献
11.
12.
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
13.
14.
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
15.
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
16.
17.
18.
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
19.
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
20.
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