查询词典 optical activity

For a peptide to act as part of the host defense system or to be of pharmaceutical interest, high antimicrobial activity must be combined by low hemolytic activity. Our results indicated that the antimicrobial activity increased with increasing charge and polar angle, with charge of ＋4 and polar angle of 140° exhibiting the highest antibacterial and membrane permeabilizing activity. Higher hydrophobicity and hydrophobic moment correlated with increased hemolytic activity, thus decreasing selectivity dramatically.

胜肽要扮演宿主免疫机制的一部分或要成为新型态的抗生素不仅要有强大的抗菌活性还需要有高度的选择性，由本实验的结果发现，当抗菌胜肽的正电荷及极性角度增加时，胜肽之抗菌活性会随之增加，当抗菌胜肽的电荷为＋4而极性角度为 140°时，胜肽有最强之抗菌能力及膜渗透活性；而随著胜肽疏水性以及疏水性矩的增加，会增加溶血活性，结果反而降低了抗菌胜肽的选择性。

The results showed that expression plasmid pET22b-lysB was constructed successfully. Highly purified recombination protein was obtained 33.2 mg from 1 L LB culture medium. A screening for His-LysB activity on esterase and lipase substrates confirmed the lipolytic activity. With p-nitrophenyl butyrate as substrate, the thermal stability of the enzyme was poor when the temperature was above 30oC. The enzyme exhibited higher stability at pH 5.0–9.5. The optimum temperature and pH for the lipolytic activity of His-LysB were 23oC and 7.5 respectively. Under the optimum conditions, the specific activity of His-LysB was 1.3 U/mg. Zn2+, Cu2+, Mg2+, Mn2+and phenylmethane sulfonyl fruoride severely inhibited the lipolytic activity of His-LysB.

结果表明：成功构建了pET22b-lysB表达载体，并从1 L的LB培养物中获得了33.2 mg高纯度重组蛋白；His-LysB具有分解脂肪的能力，属于脂肪酶；生物化学特性分析表明：丁酸对硝基苯为水解底物，His-Lys热稳定性不佳，30℃以下比较稳定，随着温度的升高，稳定性逐渐降低；该蛋白具有较高的pH值适应性，pH 5.0~9.5范围内稳定性较高；在23℃和pH 7.5时酶活力最高，其比酶活为1.3 U/mg；金属离子Zn2+、Cu2+、Mg2+、Mn2+和苯甲基磺酰氟抑制剂对酶活具有强烈的抑制作用。

Therewas a significant characteristic of the vertical distribution of soil enzyme activity,the relationship analysis indicated that there was a significant positive relationshipbetween the catalase activity and OM,and total N,and effective P、K,and ex-changible Mg,there was a negative relationship between the catalase activity andBase Situatiou percentage,and Total Contents of Base;the activity of the polyphe-nol oxidase was positively related with OM,and negatively related with total N andexchangible Ca clearly;The urease activity decreased with CPR increasing,and thechange of the former two kinds of soil enzyme actirity was not significantly withCPR increasing,It is possible to be related with maned disturbance frequently.

随着代次增加，有机质和交换性Ca下降明显；土壤的CEC和交换性酸分别下降了8.8—16.1%和6.8—18.5%，因此，其养分总量亦逐代降低，其中有机质下降幅度最大；土壤酶的活性具有明显的垂直分布特征，相关分析表明，过氧化氢酶活性与土壤OM、全N、有效P、K和交换性Mg有极显著的正相关，而与盐基总量、盐基饱和度呈明显的负相关。多酚氧化酶活性与OM呈显著负相关，与全N、交换性Ca有显著相关。脲酶活性则有随连栽代次增加而有下降趋势，前两种酶在代次之间变化不明显，可能与频繁的土壤干扰有关。

The theoretical analysis shows that the wave-activity relation presented a nonconservative form in which the pseudoenergy wave-activity density is composed of disturbance kinetic energy, available potential energy and buoyant energy. The local change of pseudoenergy wave-activity density depends on the combination of shear of zonal basic flow, Coriolis force work and wave-activity source or sink as well as wave-activity flux divergence.

理论分析表明，拟能量波作用方程具有非守恒形式，其中的拟能量波作用密度主要由扰动动能、有效位能和浮力能三部分组成；拟能量波作用密度局地变化除了受拟能量波作用通量散度影响之外，纬向基本气流切变、科氏力作功以及由非绝热加热和水汽相变所构成的波作用源汇项对其也都有贡献。

Activity of s AChE and GSTs was elevated in 4 strains,of which the activity of AChE and GSTs in KFQ strain and BYS strain was 1.57 fold and 2.33 fold respectively compared with susceptible strain.Activity of AChE and GSTs was decreased in one strain,activity of AChE was elevated but activity of GSTs was decreased in other 3 strains.

有4种品系可使AChE和GSTs活性提高，其中KFQ品系、LD品系与敏感品系相比，AChE的活性分别提高了1.57倍和1.44倍；BYS品系使GSTs活性提高了2.33倍；有3种品系可使AChE活性提高，使GSTs活性下降；另有一种品系使AChE和GSTs活性均下降。

It was shown that: 1 MMP2 activity reached the highest level during proestrus, and was lowest during diestrus; 2 MM2 acti vity was increased from the first day of pregnancy, peaked on day 4 of pregnancy; but decreased significantly at day 7 of the pregnancy. 3 MMP2 activity was obviously higher on day 1 of pseudopregnancy than on the other days, and its activity decreased gradually, reached the very low level at day 4 of pseudopregnancy and maintained the low level until day 7; 4 MMP2 activity was decreased significantly 24 hours after injection of 17βestradiol ( 01 mg) at metaestrus, while MMP2 activity had no change after progesterone (04 mg) injection.

明胶酶A活性变化如下：1在大鼠的动情前期明胶酶A的活性最高，间情期最低；2在妊娠早期(1～7天)的卵巢中，明胶酶A的活性在妊娠第4天达到最高，第1～3天及第5、6天其活性也较高，但第7天则明显下降；3在假孕(1～7天)大鼠的卵巢中，明胶酶A的活性在假孕第1天最高，第2、3天略下降，从第4天到第7天，其活性都处于较低水平；4动情后期大鼠皮下注射雌二醇(0.1mg/只)24小时后，明胶酶A活性明显上升。

Results showed that the activity of soil poly-phenol oxidases and acid phosphatase, and soil respiration were suppressed by Starane at 0.5 and 5 mgkg^(-1) dry soil, respectively, during the first several days of experiment, but were slight promoted thereafter. In contrast, treatment with Starane at 50 mgkg^(-1) stimulated at the beginning of experiment but inhibited following that time the activity of soil poly-phenol oxidases and acid phosphatase and soil respiration. Activity of urease was stimulated at the beginning but inhibited in the following days by Starane at 0.5 and 50 mgkg^(-1) dry soil, respectively. However, the pattern of stimulation of urease activity at first several days of experiment followed by reduction to the basil level was observed. With respect to invertase, its activity was constantly depressed in the presence of Starane.

结果表明使它隆在0.5mgkg^(-1)和5mgkg^(-1)质量分数时对土壤多酚氧化酶、酸性磷酸酶和呼吸强度的影响为轻微抑制－激活－恢复稳定的趋势，50mgkg^(-1)质量分数时为轻微激活－抑制－恢复稳定的趋势；使它隆在0.5mgkg^(-1)和50mgkg^(-1)质量分数时对土壤脲酶活性的影响为激活-恢复稳定的趋势，5mgkg^(-1)时则处于抑制－激活的趋势；各质量分数的使它隆浓度对土壤蔗糖酶和土壤全酚均为抑制作用，且质量分数越大抑制越强烈。

The autonomic efferent pattern of the baroreflex resetting induced by DPN stimulation was observed through recording renal sympathetic nerve activity , splanchnic nerve activity , cardiac sympathetic nerve activity , ganglioglomerular nerve activity and lumbar sympathetic nerve activity , discharge of single sympathetic fiber separated from the deep peroneal nerve and discharge of single sympathetic fiber separated from the superficial peroneal nerve , and cervical vagal efferent single fiber discharge .

通过记录肾、内脏、心、颈和腰交感神经的放电以及记录腓深和腓浅神经中交感单纤维和颈迷走传出单纤维的放电，观察了刺激DPN重调定压力感受性反射的自主神经传出型式。

Lianghe turpentine relative density, refractive index, initial boiling point, distillation range size, optical activity and chemical composition as well as the softening point, acid value, unsaponifiable matter content, ethanol insoluble matter, ash, optical activity and chemical composition and other physical and chemical characteristics of rosin gum were studied.

研究梁河脂松节油的相对密度、折光率、初馏点、馏程体积、旋光度和化学组成以及脂松香的软化点、酸值、不皂化物含量、乙醇不溶物、灰分、旋光度和化学组成等物理和化学特征。

In order to improve the precision, a new system is presented to measure the optical activity based on the theory of polarization interference. The measurement result for a quartz crystal optical activity shows that the relative error is less than one percent and the precision and effeet is improved a lot than the traditional one.

为了提高测量精度，设计了一种利用偏振光干涉法测量物质旋光率的新系统，并对石英晶体旋光性质进行了测定，测量结果的相对误差小于1%，实验证明其测试精度和使用效果都比传统方法有了明显的提高。

Warden: That's a beautiful dog, but don't bring her again.

那是条漂亮的狗，但是不要再把她带来了。

You get up in the morning – no hangover!

你第二天早上起来的时候—不会宿醉！