全子叶生物活性豆腐凝胶特性的研究

通过因子筛选实验,确定了接种量、微生物转谷氨酰胺酶(MTG)用量和水豆比是影响全子叶生物活性豆腐凝胶特性的关键因子。在此基础上,采用响应曲面法(Response SurfaceMethodology,RSM)分别建立了豆腐硬度和持水率的二次多项数学模型,验证了模型的有效性并探讨了上述3个因子的交互作用。从产品成本和凝胶特性综合考虑,选择出最佳配比,即乳酸菌接种量为105cfu/mL,MTG用量为347 U/L,水豆比为8.5,其硬度和持水率实测值分别为44.8g和89.2%,可生产出富含乳酸菌和几乎全部大豆营养的健康豆腐。     

林地土壤压实对土壤呼吸影响的数学模型研究

介绍土壤呼吸对于林地树木生长的重要性。分析人工干扰等外力作用导致土壤压实,使土壤容重增加,改变土壤孔隙度和二氧化碳浓度等。通过对影响因素和机理的分析,从微观角度利用微分原理,推导出土壤压实对土壤呼吸影响的数学模型,并就各主要影响因素对土壤呼吸的影响进行简要分析。     

Advanced glycation end products change spontaneous calcium spark morphology in cardiomyocytes

AIM:To investigate the effect of advanced glycation end products (AGEs) on the activity of rynodine receptor (RyR) and calcium regulation in cardiomyocytes, in order to clarify the underlying mechanisms of cardiac dysfunction in diabetic cardiomyopathy. METHODS:The frequency and morphology of spontaneous calcium sparks were observed in cultured neonatal rat ventricular myocytes by the imaging technique of laser scanning confocal microscope. RESULTS:Compared with control group, AGEs increased the frequency of calcium sparks, where 10 mg/L of AGEs increased by 48% (P<0.01), 50 mg/L of AGEs increased by 200% (P<0.01) and 150 mg/L of AGEs increased by 110% (P<0.01). AGEs alter the morphology of spontaneous calcium sparks. AGEs decreased the amplitude and width of calcium sparks, and calcium spark duration. AGEs increased the level of cardiomyocyte resting Ca2+. CONCLUSION: AGEs increases the frequency of spontaneous calcium sparks, thereby enhancing calcium spark-mediated leaking of sarcoplasmic reticulum Ca2+, which may be the cause of diabetic cardiomyopathy systolic dysfunction.     

Advanced oxidation protein products are generated by bovine neutrophils and inhibit free radical production in vitro

Despite the recognised importance of oxidative stress in the health and immune function of dairy cows, protein oxidation markers have been poorly studied in this species. The current study aimed to characterise markers of protein oxidation generated by activated bovine neutrophils and investigate the biological effects of advanced oxidation protein products (AOPP) on bovine neutrophils. Markers of protein oxidation (AOPP, dityrosines and carbonyls) were measured in culture medium containing bovine serum albumin (BSA) exposed to neutrophils. The effect of AOPP-BSA on generation of reactive oxygen species (ROS) was assessed by chemiluminescence. Activation of caspases-3, -8 and -9 and the presence of DNA laddering were used as apoptosis markers.Greater amounts of AOPP were generated by phorbol myristate acetate (PMA)-activated than non-activated neutrophils (1.46 ± 0.13 vs. 0.75 ± 0.13 nmol/mg protein, respectively; P < 0.05). Activated neutrophils and hypochlorous acid generated slightly different patterns of oxidized protein markers. Exposure to AOPP-BSA did not stimulate ROS production. Activated neutrophils generated a lesser amount of ROS when incubated with AOPP-BSA (P < 0.001). Activation with PMA induced a loss of viable neutrophils after 3 h, which was greater with AOPP-BSA incubation (P < 0.05). Detectable amounts of active caspases-3, -8 and -9 were found in nearly all samples but differences in caspase activation or DNA laddering were not observed comparing treatment groups. Apoptosis was unlikely to be responsible for the greater loss of PMA-activated neutrophils cultured in AOPP-BSA and it is possible that primary necrosis occurred. The results suggest that accumulation of oxidized proteins at an inflammatory site might result in a progressive reduction of neutrophil viability.     

苦荞高产栽培技术研究

[目的]探讨苦荞(Fagopyrum tataricum)高产栽培技术措施。[方法]采用二次回归正交旋转组合设计试验,研究种植密度(43.2万、52.5万、75.0万、97.5万、106.8万株/hm2)、复合肥施用量(281.8、375.0、600.0、825.0、918.2 kg/hm2)对苦荞产量的影响。[结果]种植密度和施肥对苦荞产量影响显著,都表现为低水平下呈正效应,高水平下呈负效应,并且互作效应显著。获得产量高于2 100 kg/hm2的合理取值区间为:种植密度84.50万~102.97万株/hm2,施肥320.33~505.05 kg/hm2。建立的数学模型Y=2 208.63+122.53X1-114.33X2-200.91X21-205.58X22-184.85X1X2的拟合程度较好,对苦荞生产具有实际指导作用。[结论]该研究可为苦荞高产优质生产提供技术参考。     

一种新型的牡丹各持资源——牡丹高代杂种

牡丹高代杂种属于牡丹革质花盘亚组与肉质花盘亚组间的远缘杂种，在育种及应用领域有着巨大潜力。本文介绍了牡丹高代杂种的育种历史、生物学特性，并结合我国牡丹种质资源的特点，阐述了牡丹高代杂种在我国的科学价值和应用前景。     

夏大豆植株干物质积累数学模拟研究

对夏大豆濉科8号、中黄13两个品种从出苗至成熟共15次测定了植株质量,建立了数学模型。结果表明:植株、茎叶质量呈"慢—快—慢—降"的单峰变化趋势,而籽粒质量呈"慢—快—慢"的S形曲线变化趋势,单株粒重、百粒重则随生育时期呈直线增长趋势。y=ef(t)真实的反映了出苗、始花、终花至成熟期植株、茎叶质量变化。     

洋葱苯丙氨酸解氨酶基因AcPAL2的克隆与表达分析

利用简并PCR技术和RACE技术克隆得到了一条洋葱的苯丙氨酸解氨酶(PAL)基因全长cDNA序列。该cDNA序列全长2349 bp,编码长685个氨基酸残基的多肽序列,命名为AcPAL2。Blast分析表明该序列与虎眼万年青Galtonia saundersiae、野蕉Musa balbisiana的相似性均较高。Real-time PCR表达及花青素含量分析表明,红皮洋葱该基因表达量最大,而黄皮和白皮洋葱表达量极低;在红皮洋葱中该基因在膨大初期大量表达,并迅速降低至一定程度后趋于相对平稳表达,且与花青素的积累过程相一致。     

Quantitative trait loci (QTL) affecting sugars, organic acids and other biochemical properties possibly contributing to flavor, identified in four advanced backcross populations of tomato

Although the Advanced Backcross strategy has proven very useful for QTL detection in tomato, it has been used mainly in identifying QTL for agronomic traits such as yield, color, etc. Tomato flavor is an important quality characteristic, yet it has been difficult to assess flavor or traits that affect it. In this study the AB-QTL strategy was applied to four advanced backcross populations to identify QTL for biochemical properties that may contribute to the flavor of processed tomatoes, such as sugars and organic acids. A total of 222 QTL were identified for 15 traits, including flavor as assessed by a taste panel. Correlations of certain biochemicals with flavor and possible methods of assessing and improving flavor are discussed. In particular, QTL with very significant effects associated with the ratio of sugars/glutamic acid, a trait highly correlated with improved flavor, have been identified as good targets for future work in improving the flavor of tomatoes. This revised version was published online in August 2006 with corrections to the Cover Date.     

套作玉米产量与栽培密度及氮磷钾肥施用量的关系

采用二次回归通用旋转组合设计方法试验,以马铃薯套作玉米产量为目标,以套作的玉米密度、氮、磷、钾肥施用量为探讨对象,建立了套作玉米产量与密度、氮、磷、钾肥施用量间关系的数学模型(y=7396.05-536.7x1 129.0x2 135.6x3 104.7x4-19.65x1x2-5.4x1x3 147.75x1x4 165.15x2x3-86.55x2x4 113.7x3x4-478.8x12-407.7x22-446.25x32-450.3x42),通过模拟寻优,提出了玉米产量≥6750.00kg/hm2的综合农艺栽培方案(玉米密度44856-51135株/hm2,平均48000株/hm2;N279.30-350.70kg/hm2,平均315.00kg/hm2;P2O5189.00-231.00kg/hm2,平均210.00kg/hm2;K2O167.70-222.30kg/hm2,平均195.00kg/hm2。N:P:K=1:0.667:0.619)。