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51.

Background

Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.

Methods

Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (Alb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-40FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.

Results

Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.

Conclusions

These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows.  相似文献   
52.
【目的】土壤微生物量碳、氮是植被所需碳、氮的重要“源”或“库”,是公认的综合评价土壤质量或肥力的重要指标,也是土壤生态系统变化的预警及敏感指标,研究其动态变化,可为退耕还林及后期管理决策提供科学依据,并为深入研究林地碳氮循环及温室气体排放提供参考。【方法】以农田( FL)为对照,研究华北土石山区10年生刺槐林、43年生刺槐林、自然恢复植被( NRV)土壤微生物量碳、氮的四季动态变化,并对各样地微生物量碳、氮对土壤营养库的贡献率进行对比研究。【结果】各样地微生物量碳、氮随土层加深而逐渐下降,其季节动态变化差异显著;农田、自然恢复植被、10和43年生刺槐林地0~20 cm 土层微生物量碳、氮含量四季均值分别为251.94,290.68,150.66,197.34 mg·kg -1和30.95,46.46,36.55,45.27 mg·kg -1。其中:自然恢复植被的微生物量碳、氮含量四季均值最高,其微生物量碳含量分别是农田、10和43年生刺槐林的1.15,1.93和1.47倍,微生物量氮含量分别是它们的1.50,1.27和1.03倍;土壤微生物量碳、氮含量随刺槐树龄增大而升高,43年生刺槐林0~20 cm 土层的微生物量碳、氮含量是10年生刺槐林的1.31和1.24倍。各植被样地不同层次土壤微生物量碳氮比季节差异明显,农田、自然恢复植被、10年和43年生刺槐林 0~20 cm 土层碳氮比四季均值分别为8.64,6.26,4.12 和4.36;10,43年生刺槐林碳氮比分别是农田的0.48和0.50倍,是自然恢复植被的0.66和0.70倍。在 0~20 cm 土层中,农田、自然恢复植被、10和43年生刺槐林地微生物量碳对土壤有机碳平均贡献率分别为1.88%,2.00%,1.54%和1.24%,土壤微生物量氮对土壤全氮的平均贡献率分别为1.21%,5.44%,3.55%和2.26%。【结论】各样地土壤微生物量碳、氮之间显著相关,它们与土壤全氮、有机质和速效钾含量均显著相关;除此之外,土壤微生物量碳还与土壤硝态氮含量显著相关。随着树龄的增加刺槐林土壤微生物量尤其是微生物量氮含量显著提高,因而土壤的生物肥力也显著提高;由土壤微生物量碳、氮含量及其对土壤营养库的贡献率可知,自然恢复植被更利于土壤微生物结构、功能的恢复和生物活性的改善。  相似文献   
53.
为了探究不同外包滤料条件下的暗管排水性能和土壤脱盐效果,基于室内试验研究成果,在田间设置4种暗管排水系统(各系统中暗管埋深均为80 cm,间距均为20 m),所用外包滤料分别为68 g/m2土工布(L)、砂滤料(S)、68 g/m2土工布+砂滤料(LS)和无外包滤料(W),以当地常规明沟排水(CK)作为对照,通过田间试验分析了春灌过程中各暗管系统的排水性能指标及土壤脱盐效率.结果表明:相比处理W,处理L,S和LS平均排水速率提升了7.44%,12.55%和15.75%,平均流量衰减度降低4.07%;处理S和LS累积排水量提高了5.11%和8.31%(P<0.05).各暗管处理春灌后平均土壤脱盐率均达47%以上,较CK提升显著,其中处理LS效果最优,为50.94%.综上,应优先选择处理LS作为河套灌区暗管排水系统外包滤料布设方案.该研究结果可为河套灌区暗管排盐技术的推广应用提供理论支撑和科学指导.  相似文献   
54.
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents.  相似文献   
55.
The effects of citrus flavonoids on P-glycoprotein (P-gp)-mediated drug efflux were examined in human intestinal Caco-2 cells. The cellular accumulation of rhodamine-123 was measured using 10 citrus flavonoids for preliminary screening. Among the flavonoids tested, diosmin significantly increased the accumulation of rhodamine-123 in Caco-2 cells. In the bidirectional transport of digoxin, diosmin increased the apical-to-basal (A-to-B) transport but decreased the basal-to-apical (B-to-A) transport in both concentration- and time-dependent manners. The digoxin transport ratio (B-A/A-B) was estimated to be 2.3 at a concentration of 50 microM of diosmin, which was significantly lower than the 15.2 found in the control. The apparent Ki values for P(app,A-B) and P(app,B-A) were 16.1 and 5.7 microM, respectively. These results demonstrated that diosmin effectively inhibited the P-gp-mediated efflux in Caco-2 cells. Diosmin is one of the main components in citrus fruits, and the intake of food supplements containing this compound may potentially increase the absorption of drugs able to act as P-gp substrates. The clinical relevance of this interaction should be further evaluated using in vivo experiments.  相似文献   
56.
本研究以筇竹与黄皮树人工混交林中筇竹地上部分为研究对象,测定分析了1~4年生分株地上部分各构件生物量及含水率,建立人工筇竹分株地上部分各构件的生物量及总生物量模型,以期为人工筇竹林的经营管理及其碳汇项目的开发提供科学依据。结果表明:随着筇竹分株年龄的增加,各构件含水率和生物量均逐渐减少,筇竹1~4年生分株地上部分平均含水率分别为57.62%、53.40%、50.01%、42.66%,平均生物量分别为133.99、123.31、109.76、85.39 g/m2;各年龄分株地上部分生物量的分配均呈现出秆>枝>叶的变化规律。不同年龄分株的胸径与秆、枝、叶生物量及地上部分总生物量均有极显著相关性(P<0.01)。以胸径为自变量建立的各年龄筇竹分株地上部分总生物量模型的决定系数(R2)均在0.93以上,具有较高的可信度,也有着较强的适用性,可用于类似立地条件下的筇竹分株生物量估测。  相似文献   
57.
娇红2号为红花玉兰系列新品种,具有极高观赏价值,但是红花玉兰娇红2号移栽后缓苗时间较长.为了缩短移栽缓苗期,促进苗木正常生长,尝试对红花玉兰娇红2号施用ABT-1号生根粉和EM菌剂,并分析其苗木生长发育过程,为揭示移栽后苗木生长响应规律及引种推广提供参考.以1年生红花玉兰娇红2号嫁接苗为试验材料,使用不同质量分数的ABT-1号生根粉和EM菌剂进行浸根、浇水试验.设置对照(CK)、A1、A2、A3、A4、B1、B2、B3、B4共9个处理,分别于5月、7月、9月进行生长指标和生理指标测定,分析各处理的苗木生长发育情况.结果 表明:各处理与对照相比,苗木根系生长恢复期缩短和结合体内保护酶系统的正向调节,促进了苗木正常生长;A3处理(ABT-1号生根粉)可缩短缓苗期2个月左右,用生根粉处理比EM菌剂处理的效果要好;A3处理(ABT-1号生根粉)能明显促进移栽苗木根系2-3级细根的分化吸收运输水分和营养,并通过提高净光合速率和调节自身保护酶系统活性,促进苗木恢复正常生长状态,缩短缓苗期2个月左右.  相似文献   
58.
In human or mouse, mature T cells express either CD4 or CD8, resulting in different functions in the periphery. Interestingly, porcine CD4 and CD8 double positive (DP) T cells are present in the blood, and their proportions change from youth to adulthood. However, the features of these cells in swine are poorly understood. We investigated the fate of porcine peripheral T cells based on their functional characteristics, including proliferation and the expression of CD4 and CD8 co-receptors. The results showed that all the populations changed their CD8 expression in a time-dependent manner and porcine T cells had different proliferative pattern from human T cells. The results further revealed that Th2 cytokines were increased later in porcine T cells compared to human T cells upon stimulation with IL-2 + PMA. Collectively, we found that the fate of porcine peripheral T cells is different from that of human T cells, and the changes occur in a time- and stimulation-dependent manner.  相似文献   
59.
本试验旨在比较酵母硒和亚硒酸钠对蛋鸡生产性能、蛋品质和蛋硒含量的影响,以确定能够替代亚硒酸钠的酵母硒适宜使用量。试验选用30周龄体况良好、产蛋率接近的健康海兰褐蛋鸡360只,随机分成5个组,每组6个重复,每个重复12只。对照组饲喂基础饲粮(不额外添加硒源),试验组饲喂在基础饲粮中分别添加0.30 mg/kg硒的亚硒酸钠以及0.10、0.20和0.30 mg/kg硒的酵母硒(试验饲粮中实测硒含量分别为0.176、0.342、0.278、0.302、0.359 mg/kg)。预试期14 d,正试期28 d。结果表明:1)各试验组产蛋率、平均蛋重、平均日产蛋重、平均日采食量、料蛋比和蛋品质与对照组相比较差异均不显著(P>0.05)。2)亚硒酸钠组和酵母硒组蛋硒含量均显著高于对照组(P<0.05);酵母硒组蛋硒含量均显著高于亚硒酸钠组(P<0.05),并随酵母硒添加量的增加显著增加(P<0.05)。由此可见,相对于亚硒酸钠,蛋鸡对酵母硒吸收和向鸡蛋中的转移效率更高;饲粮添加硒能显著提高蛋硒含量,且蛋硒含量随着酵母硒添加量的增加而增加;饲粮中添加0.10~0.30 mg/kg硒的酵母硒对蛋鸡生产性能和蛋品质无不良影响。  相似文献   
60.
Various somatic cell nuclear transfer (SCNT) techniques for mammalian species have been developed to adjust species-specific procedures to oocyte-associated differences among species. Species-specific SCNT protocols may result in different expression levels of developmentally important genes that may affect embryonic development and pregnancy. In the present study, porcine oocytes were treated with demecolcine that facilitated enucleation with protruding genetic material. Enucleation and donor cell injection were performed either simultaneously with a single pipette (simplified one-step SCNT; SONT) or separately with different pipettes (conventional two-step SCNT; CTNT) as the control procedure. After blastocysts from both groups were cultured in vitro, the expression levels of developmentally important genes (OCT4, NANOG, EOMES, CDX2, GLUT-1, PolyA, and HSP70) were analyzed by real-time quantitative polymerase chain reaction. Both the developmental rate according to blastocyst stage as well as the expression levels CDX2, EOMES, and HSP70 were elevated with SONT compared to CTNT. The genes with elevated expression are known to influence trophectoderm formation and heat stress-induced arrest. These results showed that our SONT technique improved the development of SCNT porcine embryos, and increased the expression of genes that are important for placental formation and stress-induced arrest.  相似文献   
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