乳酸

Finally,the process conditions establish foundation of biotransformation for utilizing starchiness,expand raw material source,and reduce cost of producing lactic acid. And the process conditions of producing L－lactic acid from potato starch were established and provide the scientific foundation for commercial process.

探索出利用马铃薯淀粉为原料直接发酵制备L－乳酸的生产工艺条件，为综合利用淀粉质等生物质原料进行生物转化奠定了基础，并拓宽和增加了发酵生产L－乳酸的原料来源渠道，降低L－乳酸的生产成本，为大规模工业化生产L－乳酸提供了科学依据。

For lactic acid has one asymmetric carbon atom, the mechanical, physical and biological properties of PLA are related to the stereochemistry of lactic acids.

合成聚乳酸的初始物质―乳酸是有手性的分子，使得聚乳酸的机械和物理性能以及生物学性质与乳酸单体的立体异构性有关。

In the traditional lactic acid production methods, DL-lactic acid can be synthesized by chemosynthesis method, its cost is too high and its raw materials are venomousness; Optical purity lactate can be produced by Enzyme catalysis. Due to it"s more complicated technology and it"s high demanding for working condition, microbial fermentation has become the important method to produce lactic acid.

传统的乳酸生产方法中，化学合成法所用原料有剧毒，生产成本高：酶法生产乳酸工艺比较复杂，对生产条件要求较高，因此微生物发酵法生产乳酸成为乳酸生产的主要方法。

Objective TO compare the different changes of blood lactate and blood gases when given the lactated Ringer's solution and acetated sodium solution during operation. Methods 40 patients are divided equally into the lactated Ringer's group and the acetated sodium grouprandomly,adapting the combined intravenous and inhalation general anesthesia. The lactated Ringer's gis given in group L and the acetated sodium in group A. Neither groups are cross-given other crystal solution during operation, polygeline is the only colloid solution in both groups.

目的 比较术中输入乳酸钠林格液和醋酸钠林格液血乳酸盐及血气的变化方法 40例择期手术患者按随机字表随机分乳酸钠组和醋酸钠组，每组各20例，采用静吸复合全身麻醉。L组术中输入乳酸钠林格液，A组术中输入醋酸钠林格液，两组术中不交叉输入其他晶体液，输入胶体液均为菲克血隆。

The biomechanical tests showed that two kinds of artificial bones had not significant difference on compressive strength and Young\'s modulus(P＞0.05),while the flexural strength of nano-nacre artificial bone was less than the control group(P＜0.05).3.The results of CCK-8 showed that the difference were not significant in each group,the proliferation of osteoblast reached the peak at the 5th day;7 days after being co-cultured,the total protein content of study group was higher than control group and blank group(P＜0.05),while the difference between control group and blank group was not significantP＞0.05The difference of alkaline phosphatase activities among three groups was not significant(P＞0.05The SEM view showed that osteoblast attached and grew well in two kinds of artificial bone.4.X-ray photography showed that two kinds of powder started to degrade in 2 weeks;this phenomenon became more appear in 4 weeks,nano-nacre powder degraded faster than micron-nacre powder,while the hole shadow was easy to be found;in 8 weeks,all the femoral holes recovered and returned to normal bone mineral density in all groups.Analysis of tetracycline fluorescent double marks in the hard tissue grinding slices indicated that new bone grew fastest around the bone defect area in study group,while most slowly in blank groupP＜0.05 SEM(scanning electron microscope observation showed that nano-nacre powder degraded more quickly.The same result can be found through the demineralized sections morphometric analysis,and both of the composite artificial bones made from those two kinds of nacre powder had the good connection with the adjacent tissue in rats body without apparent inflammatory response.5.X-ray photography showed that rabbit\'s bone defects healed faster in study group since NNAB implanted than in control group since MNAB implanted.At 24 weeks after operation,bone density in radial defects had nearly accessed to the normal area,while lower in control group,and turned up nonunion in blank group;The checking of BMD showed that results in study group were higher than those in control group at 8,16 and 24 week(P＜0.05), and the difference between the BMD values in study group at 24 week and those in blank group was not significant(P＞0.05).The gross specimens showed satisfactory histocompatibility both in study group and in control group,with bone tissue growing from two sides into the center of implanted materials; Normal slices in HE stain and hard tissue grinding slices in Stevenel\'s blue/Van Geison\'s picro-fuchsin stain showed that the bone growth tendency was better in study group than that in control group,and the medullary cavity had been penetrated to the implanted materials in study group at 24 week;Analysis of tetracycline fluorescent double marks in the hard tissue grinding slices indicated that new bone in both groups grew fastest 8 weeks after surgery,while slow down at 16 week.

纳米珍珠层/消旋聚乳酸复合人工骨与微米珍珠层/消旋聚乳酸复合人工骨分别与成骨细胞共培养后，其各时间点CCK-8法检测值与空白对照无显著差异(P＞0.05)，成骨细胞均在第5天达到增殖高峰期；培养7天后，实验组细胞蛋白含量高于对照组及空白组(P＜0.05)，后两者之间则无显著差异P＞0.05碱性磷酸酶活性在三组间均无显著差异(P＞0.05电镜下可见成骨细胞在两种人工骨上都有良好生长贴附能力。4.X-ray显示两种粉体在大鼠股骨骨洞植入第2周时都开始出现了降解，第4周时更为明显，纳米珍珠层粉较之微米珍珠层粉降解更快，而空白对照组骨洞阴影仍可见，至8周时，则所有组骨洞均己闭合修复，X-ray下已不可见原钻孔痕迹，恢复正常骨质密度；硬组织磨片四环素荧光双标记结果显示纳米珍珠层粉植入组较其余两组在骨缺损区周围新骨生长速度更快，空白组速度最慢P＜0.05电镜观察及常规脱钙切片亦可见到纳米粉体降解较快；由以上两种原材料制得的纳米珍珠层/消旋聚乳酸复合人工骨与微米珍珠层/消旋聚乳酸复合人工骨在大鼠体内均与周围组织结合良好，无明显炎症反应。5.X-ray显示纳米珍珠层/消旋聚乳酸复合人工骨植入兔桡骨缺损区后其骨愈合速度较对照组微米珍珠层/消旋聚乳酸复合人工骨植入的快，至植入术后24周，实验组骨缺损区接近正常骨密度，对照组骨缺损区密度较低，空白组则呈现骨不连状态；骨密度测量结果显示术后8周、16周、24周实验组的骨密度值高于对照组(P＜0.05，24周实验组的骨密度值与术前所测得的正常值无显著性差异P＞0.05动物取材大体所见均显示组织相容性良好，骨组织逐渐由植入材料两端向中央生长；常规切片HE染色及硬组织磨片Stevenel\'s blue/Van Geison\'s picro-fuchsin联合染色均可见实验组骨缺损区长势优于对照组，至术后24周，实验组骨髓腔与材料已呈相交通状；硬组织磨片荧光显微镜下观察，两组材料在术后8周处于骨生长最快速时期，16周时速度开始减慢，术后4、8、16周时实验组的新骨生长速度均较对照组的快

Both direct synthesis and ring-opening polymerization can be utilized to prepare homo- and copolymers of lactic acid such as L-lactide, D-lactide, D, L-lactide, and glycolide.

直接聚合和开环聚合两种方法可以用来制备乳酸的均聚物和共聚物，如聚L乳酸、聚D乳酸、聚D，L乳酸和L乳酸乙醇酸共聚物。

The main gluconeogenic precursor in kidney is thought to be lactate; however, less is emphasized enantiomerically. L-lactate is a glycolysis end-product, but D-lactate is formed after detoxification of methylglyoxal, which is the main source of advanced glycation end-products.

乳酸为肾脏糖质新生的主要来源，其含有一不对称碳，故具有D-、L-乳酸两种镜相异构物，而D-、L-乳酸两者之生成相当不同，L-乳酸是糖解作用之终产物，D-乳酸为体内一醣化终产物(advanced glycation end-products)─甲基乙二醛进行去毒化反应所生成，目前缺乏对乳酸镜像异构物与肾脏糖质新生间相关的探讨。

Form PLA is a nonvirulent macromolecular compound with biocompatibility, which used in the manufacture of new biodegradable plastics, fiber, and biomedical material.

型乳酸，分子式C3H6O3，为含有氢氧基的有机酸，是生物的代谢中间产物。L型乳酸可以在动物和人类细胞中新陈代谢因为这些细胞含有L型乳酸去氢酵素。L型乳酸还可用於生产L型乳酸聚合物。L型乳酸聚合物属於无毒的高分子化合物，具有生物相容性，可用於制造生物可分解的塑胶、纤维以及生医材料等。

BrightChina is devoted to development of lactic acid and poly-lactic acid industry where the renewable plant resources can be used as raw material, and the products include lactic acid and its derived lactates, lactic esters,poly-lactic acid, and other environment- friendly outputs.

公司致力于发展乳酸及聚乳酸产业。这已产业以可再生性植物资源为原料，产品包括乳酸及其衍生的乳酸盐类、乳酸酯类和聚乳酸等环境友好产品。

Poly lactic acid is a biodegradable and processable high polymer, which is widely used in chemical engineering, agriculture and pharmaceutical industry. D-LA is hence going to form a huge potential market. Fermentative production of D-LA by microorganisms is the primary method in industry, which is applied by several factories abroad.

聚乳酸因具有优良的生物可降解性和加工性能，应用于化工、农业和医药等方面，因而D-乳酸市场潜力巨大。D-乳酸的工业生产主要应用微生物发酵法，国外已有2~3家D-乳酸生产企业，而我国目前尚无D-乳酸制备研究或工业化生产的报导，该技术亟待发展。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。