LC-MS/MS法同时测定复方丹参颗粒和复方丹参滴丸中6种成分

目的建立LC-MS/MS法同时测定复方丹参颗粒和复方丹参滴丸(丹参、三七、冰片)中丹参素钠、三七皂苷R1、人参皂苷Re、人参皂苷Rg1、人参皂苷Rb1、丹参酮ⅡA的含有量。方法 2种药物75%甲醇提取液的分析采用Eclipse Plus C18色谱柱(3. 0 mm×150 mm,3. 5μm);流动相乙腈-0. 1%甲酸,梯度洗脱;体积流量0. 3 m L/min。结果 6种成分在各自范围内线性关系良好(R2≥0. 995 9),平均加样回收率95. 76%～105. 74%,RSD 1. 86%～4. 88%。除丹参素钠外,其他5种成分在复方丹参颗粒中的含有量均高于在复方丹参滴丸中。结论复方丹参颗粒和复方丹参滴丸中主要成分含有量有明显差异,可能会影响临床疗效。

自乳化药物传递系统的生物药剂学性质概述

自乳化药物传递系统因其能增加难溶性和亲脂性药物体内生物利用度,一直都是研究的热点。本综述总结了自乳化药物传递系统的生物药剂学性质,为研究自乳化药物传递系统提高药物生物利用度的机制提供参考。

Effect of polyamine on seed germination of wheat under drought stress is related to changes in hormones and carbohydrates

Drought is a multifaceted stress condition that inhibits crop growth. Seed germination is one of the critical and sensitive stages of plants, and its process is inhibited or even entirely prevented by drought. Polyamines （PAs） are closely associ- ated with plant resistance to drought stress and seed germination. However, little is known about the effect of PA on the seed germination of wheat under drought stress. This study investigated the involvement of PAs in regulating wheat seed germination under drought stress. Six wheat genotypes differing in drought resistance were used, and endogenous PA levels were measured during seed germination under different water treatments. In addition, external PAwas used for seed soaking and the variation of hormones, total soluble sugar and starch were measured during the seed germination under different water treatments. These results indicated that the free spermidine （Spd） accumulation in seeds during the seed germination period favored wheat seed germination under drought stress; however, the free putrescine （Put） accumulation in seeds during the seed germination period may work against wheat seed germination under drought stress. In addition, seed soaking in Spd and spermine （Spm） significantly relieved the inhibition of seed germination by drought stress; howev- er, soaking seeds in Put had no significant effect on seed germination under drought. External Spd and Spm significantly increased the endogenous indole-3-acetic acid （IAA）, zeatin （Z）＋zeatin riboside （ZR）, abscisic acid （ABA）, and gibberellins （GA） contents in seeds and accelerated the seed starch degradation and increased the concentration of soluble sugars in seeds during seed germination. This may promote wheat seed germination under drought stress. In conclusion, free Spd and Put are key factors for regulating wheat seed germination under drought stress and the effects of Spd and Put on seed germination under drought notably related to hormones and starch metabolism.

Effects of Water-Collecting and -Retaining Techniques on Photosynthetic Rates, Yield, and Water Use Efficiency of Millet Grown in a Semiarid Region

Field experiments were conducted in 2003 and 2004 to study the effects of plastic ridges and furrow film mulching （plastic film on sowing, as well as plastic film on flat soil and hole sowing） and chemicals （a drought resistant agent and a water- retaining agent） on growth, photosynthetic rate, yield, and water use efficiency （WUE） of spring millet （Setaria italica L.）. The experimental results showed that water-collecting and -retaining techniques can effectively increase soil moisture content, the leaf photosynthetic rate and crop growth. Due to increased soil moisture under the plastic-covered ridge and furrow water-collecting in July and August, dry matter and plant height had a increase at the booting stage （late growth advantage）. However, the plastic-covered flat soil and hole sowing reduced soil evaporation during early growth, the increase of dry matter and plant height appeared at the seedling stage （early growth advantage）. Plastic-covered ridge and furrow sowing supplemented with chemical reagents had significant positive effects on water collection and soil moisture retention. Improvement of soil moisture resulted into the increase of the photosynthetic rate, dry matter accumulation yield and WUE. The water-collecting and -retaining techniques can improve WUE and enhance crop yield. Correlation analysis demonstrated that the photosynthetic rate under the water-collecting and -retaining techniques was significantly associated with the soil moisture, but had no significant relationship with leaf chlorophyll content. Plastic- covered ridge and furrow sowing supplemented with chemical reagents increased the yield and WUE by 114% and 8.16 kg ha-1 mm-1, respectively, compared with the control; while without the chemical reagents the yield and WUE were 95% and 7.42 kg ha-1 mm-1 higher, respectively, than those of the control.

Cladosporium sp.AY-42固态发酵产纤维素酶条件优化

为了提高高产纤维素酶菌株Cladosporium sp.AY-42的产酶能力,采用单因素实验和响应面优化实验对固态发酵产酶条件进行优化。结果表明:培养基的最适碳源为油菜秸秆粉∶麸皮为3∶2,最适氮源为(NH4)2SO4及最适氮源浓度为2%。最佳培养条件为料水比1∶1.8,温度29℃,发酵时间4d,优化后的固态发酵培养菌株CMC酶活最终达(8.17±0.05)IU,酶活力提高了57.72%。该研究将为枝孢菌在纤维素酶发酵生产方面提供一定理论基础。

The Effect of Plastic-Covered Ridge and Furrow Planting on the Grain Filling and Hormonal Changes of Winter Wheat

Although plastic-covered ridge and furrow planting（RF） has been reported to produce substantial increases in the grain weight of winter wheat,the underlying mechanism is not yet understood.The present study used two cultivars,Xinong 538 and Zhoumai 18,and RF and traditional flatten planting（TF,control） with the objective of investigating the effect of RF on wheat grain filling and the possible relationship of hormonal changes in the wheat grains under RF to grain filling.The results indicated that RF significantly increased the grain weight,although the effects on grain filling were different： RF significantly increased the grain-filling rate and grain weight of inferior grains,whereas RF had no significant effect on grainfilling rate and grain weight of superior grains.The final grain weight of inferior grains under RF was 39.1 and 50.7 mg for Xinong 538 and Zhoumai 18,respectively,3.6 and 3.4 mg higher than the values under TF.However,the final grain weight of superior grains under RF was only 0.6 and 0.8 mg higher than under TF for Xinong 538 and Zhoumai 18,respectively.RF significantly decreased the ethylene and gibberellic acid content in the inferior grains and increased the indole-3-acetic acid,abscisic acid and zeatin ＋ zeatin riboside content in the inferior grains;however,no significant difference between RF and TF was observed for the hormonal content in the superior grains.Based on these results,we concluded that RF significantly modulated hormonal changes in the inferior grains and,thus,affected the grain filling and grain weight of the inferior grains;in contrast,RF had no significant effect on grain filling,grain weight and hormonal changes in the superior wheat grains.

某型微型客车发动机舱热管理仿真优化设计

对一款微型客车在爬坡工况下发动机舱的流场及温度场进行了仿真分析,发现发动机舱内出现涡流及回流,部分部件超过容许温度等现象。利用网格变形软件、计算流体力学仿真软件及多目标优化软件建立多学科融合的联合仿真优化模型,通过在下进气格栅后部加装导流板,实现导流板竖向偏角的参数化,将超过容许温度部件的最高温度点、冷凝器和散热器的进气流量作为优化目标,对导流板角度进行优化设计,得到该微型客车下进气格栅导流板的最佳角度为:上导流板10°,下导流板-8°。

Improved Efficiency Droop in a GaN-Based Light-Emitting Diode with an AlInN Electron-Blocking Layer

GaN-based light-emitting devices(LEDs)with different electron blocking layers are theoretically studied and compared by using the advanced physical models of a semiconductor device simulation program.It is found that the structure with an AlInN electron blocking layer shows improved light output power,lower current leakage and efficiency droop.Based on numerical simulation and analysis,these improvements of the electrical and optical characteristics are mainly accounted for by efficient electron blocking.It can be concluded that Auger recombination is responsible for the dominant origin of the efficiency droop of a GaN-based LED as current increases.