营养补偿初期苏尼特母羊对NDF、ADF消化能力的研究

将45只处于妊娠后期(90～150d)的苏尼特母羊随机分成4组,以不同的营养水平(代谢能:0.20、0.33、0.44、0.86MJ/kgW0.75·d)分组饲养,分娩后进行补偿生长试验,研究妊娠后期不同营养限制程度的母羊在补偿初期(分娩后0～6周)对中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)消化率的影响。结果表明:在补偿初期,各组母羊对ADF、NDF的消化率随着营养限制程度的增强而下降。     

哺乳犊牛的消化特点与蛋白质需要

本文从犊牛的消化生理特点出发,综述了犊牛出生后的生理特征及蛋白质、必需氨基酸的需要量,并对代乳品中蛋白质原料进行了论述。     

不同月龄生长公牛日粮营养物质消化规律的研究

本试验选用3头6月龄左右断奶中国荷斯坦公牛,在试验全程喂以相对稳定的日粮,从2003年11月1日开始,到2004年6月20日结束,用以测定中国荷斯坦生长公牛在不同生长期对饲粮中各营养成分的代谢情况。试验结果表明:日粮中的DM、OM、NDF、ADF、淀粉和粗蛋白质的表观消化率随着生长犊牛的月龄的增加而增加(P<0.05);并且9月龄以后,DM、OM、NDF、ADF和粗蛋白质的表观消化率增长不明显(P>0.05),淀粉的表观消化率则在11月龄以后增长不明显(P>0.05)。氮的净吸收率随着生长犊牛的月龄的增加而下降(P<0.05),且在9月龄以后下降不明显(P>0.05)。     

Whole-Cell Fatty Acid Composition to Characterize and Differentiate Isolates of Rhizoctonia Species Associated with Turfgrass Diseases in Japan

Cellular fatty acids were analyzed to characterize and differentiate 34 isolates of Rhizoctonia species representing binucleate Rhizoctonia AG-D (I), AG-D (II), R. solani AG 2-2 IIIB, AG 2-2 LP, R. circinata var. circinata and var. oryzae associated with turfgrass diseases in Japan. Myristic, pentadecanoic, palmitic, palmitoleic, stearic, oleic, linoleic and linolenic acids were consistently present in varying quantities in all isolates. Heptadecanoic and 9-heptadecenoic acids were present in isolates of Rhizoctonia AG-D (I), AG-D (II), R. solani AG 2-2 IIIB and AG 2-2 LP but not in isolates of R. circinata var. circinata and var. oryzae. Palmitic, oleic and linoleic acids were the major fatty acids found, constituting 88.30-98.37% of the whole-cell fatty acid content. The remaining fatty acids were present in smaller amounts. Isolates within a single group were closely clustered, whereas isolates from different groups were clearly distinguishable based on average linkage cluster analysis of cellular fatty acids. Principal component analysis, based on all fatty acids detected, confirmed the distinct separation of isolates representing the six groups of Rhizoctonia species obtained from turfgrasses. These results suggested that fatty acid analysis is useful for the characterization and differentiation of isolates of Rhizoctonia species associated with turfgrass diseases. Received 21 May 2001/ Accepted in revised form 28 September 2001     

地高辛标记核酸探针的标记方法及其在食用菌研究领域的应用

综述了非放射性地高辛（DIG）标记系统的原理和主要特点，介绍了地高辛标记核酸探针的主要标记方法，影响探针标记方法选择的因素，标记探针的显色检测方法及其在食用菌研究领域的应用。     

Effects of riboflavin and ascorbic acid on apoptosis and proliferative inhibition of mouse thymocytes induced by deoxynivalenol in vivo

AIM: To explore the effects of riboflavin and ascorbic acid on the apoptosis induced by deoxynivalenol(DON) in mouse thymocytes. METHODS: The effects of riboflavin and ascorbic acid on the apoptosis and proliferation inhibition of thymocytes induced by DON in KM mice were studied with animal experiment, DNA agarose gel electrophoresis and flow cytometric DNA content analysis. RESULTS: Apoptosis rate of thymocytes in DON (4 mg/kg) treated group was13.73%±15.3% The percentages of apoptosis in riboflavin (1.25 mg/kg-10mg/kg) and ascorbic acid (25 mg/kg-100mg/kg) pretreated thymocytes groups were significantly lower than that in DON group (P <0.05). The result of DNA agarose gel electrophoresis showed that the characteristic ladder pattern of apoptosis was found in DON-treated thymocytes, but not in control and riboflavin pretreatment and ascorbic acid pretreatment groups The significant differences in proliferation index were not found among DON-treated thymocytes and riboflavin and ascorbic acid-pretreated thymocytes CONCLUSION: Pretreatment with riboflavin and ascorbic acid inhibit apoptosis of mouse thymocytes induced by DON in certain extent and have no effect on proliferation inhibition by DON.     

Effects of tetrandrine and fructose-1, 6-diphosphate on the elevated intrasynaptosomal [Ca2+]i induced by excitatory amino acids

AIM: To study the effects of tetrandrine(Tet) and fructose-1, 6-diphosphate(FDP) on the elevated intrasynaptosomal [Ca²⁺]_i induced by excitatory amino acids(EAA). METHODS: A rapid method for preparing synaptosomes was used, and intrasynaptosomal free calcium([Ca²⁺]_i) was measured by using the fluorescent indicator quin-2. RESULTS: L-glutamate(Glu, 100 μmol/L), aspartate(Asp, 100 μmol·L^-1), N-methy1-D-aspartate(100 μmol/L) and Glu(50 μmol/L) plus Asp(50 μmol/L) all elevated intrasynaptosomal [Ca²⁺]_i in a dose-dependent manner. Pretreatment with Tet(10, 30, 60 μmol/L), FDP(15, 30, 75, 150 μmol/L), MK-801(10, 20 μmol/L) and Tet(15, 30 μmol/L) plus FDP(15, 30 μmol/L) all attenuated the increase in intrasynaptosomal [Ca²⁺]_i induced by EAAs mentioned as above in a dose-dependent manner, and the effect of Tet plus FDP was most significant. CONCLUSION: Both Tet and FDP inhibited a rise in intrasynaptosomal [Ca²⁺]_i induced by EAAs, which may be one of mechanisms that Tet and FDP pretect cerebral tissues against ischemia injury.     

Indole-3-acetic acid biosynthesis in <Emphasis Type="Italic">Aciculosporium take</Emphasis>, a causal agent of witches' broom of bamboo

 Aciculosporium take (Ascomycota; Clavicipitaceae) is a causal agent of witches' broom of bamboo plants. The symptoms of this disease are believed to be induced by plant hormones, particularly auxins. Indole-3-acetic acid (IAA) was identified in cultures of this fungus in an l-tryptophan-supplemented liquid medium. IAA production was confirmed on 30 isolates of A. take from various hosts and locations at levels up to 1 mg/l. The biosynthetic pathway of IAA in A. take culture was examined by analyzing intermediate products and by feeding experiments. The results showed that the indole-3-pyruvic acid pathway (l-tryptophan → indole-3-pyruvic acid → indole acetaldehyde → IAA) was the dominant pathway in A. take. Received: June 3, 2002 / Accepted: July 25, 2002     

外源绿原酸对苹果抗病相关酶的影响

采用离体培养方法对富士、红星和八棱海棠进行绿原酸处理,研究苹果在外源绿原酸处理下POD、PPO、PAL活性的动态变化以及绿原酸含量的变化。结果表明,富士以0.0001%绿原酸、红星以0.0008%绿原酸、八棱海棠以0.0004%绿原酸处理后,其PAL活性均显著提高,苹果体内也因此而提高了绿原酸水平。     

苹果中多酚物质及其在果实发育过程中的变化

以秦冠、富士、嘎拉、华冠、华帅、金冠、国光、首红、澳洲青苹等9个品种为试材,对苹果果实发育过程中总酚、绿原酸、黄烷醇、原花色素含量进行了分析。结果表明,苹果果肉中多酚物质的含量和组成在不同品种间存在着较大差异;总酚、绿原酸、黄烷醇和原花色素含量在苹果发育初期迅速下降,其后下降速度逐渐减缓,最后则趋于稳定或稍有下降;在果实发育初期,绿原酸为果肉中主要的多酚物质,而黄烷醇和原花色素仅占很小的比例,但在果实发育过程中绿原酸所占比例逐渐降低,而黄烷醇和原花色素所占比例逐渐上升,成熟时已远远超过绿原酸占总酚含量的比例,成为果实中最主要的一类多酚物质。