产β-葡聚糖酶淀粉液化芽孢杆菌的选育

通过对一株淀粉液化芽孢杆菌进行紫外和^60Co逐级诱变，使该菌株产β-葡聚糖酶酶活从80U／mL提高到105U／mL；对突变株进行多次单菌落分离及传代，对其传代稳定性的研究表明：该菌株产酶性能稳定；在5L发酵罐中突变株的产酶水平比摇瓶要高，可达120U／mL，产酶周期比摇瓶缩短了15h．     

产纤溶酶米曲霉的筛选及诱变育种

利用自己设计的筛选方法，从不同的酿造曲样中筛选出1株产纤溶酶酶活较高的米曲霉菌株SA-6，其产纤溶酶酶活为25U／mL。SA-6经过紫外线、^60Co和亚硝基胍诱变，筛选得到突变株NA-25，其产酶酶活为63U／mL，是出发菌株SA-6的2．52倍。突变株NA-25的发酵性状改变，其产纤溶酶的高峰比出发菌株迟了约10h。     

枯草杆菌Bacillus sp F26产过氧化氢酶的发酵条件

从内蒙古呼伦贝尔草原的盐碱湖中分离到的一株低度嗜盐嗜碱细菌Bacillus sp F26，能积累高水平过氧化氢酶（CAT）。对Bacillus sp F26发酵产过氧化氢酶的环境与营养条件的研究结果表明，其积累高水平过氧化氢酶的适宜环境条件为：温度37℃，种龄20-22h，接种量5％，装液量50mL／（250mL的摇瓶）。适宜发酵培养基组成（g／L）为：葡萄糖15，牛肉膏10，玉米浆10，酵母膏5，磷酸二氢钾1，氯化镁0．2，氯化钠50，碳酸钠10。采用上述条件进行摇瓶分批发酵实验，发酵20h，过氧化氢酶酶活达到16．32U／mL，细胞干重为4．12g／L。进一步研究发现，在对数生长后期（16h）添加2mmol／L的H2O2可以明显刺激产酶，在5L的发酵罐上进一步以指数速率方式流加H2O2，由于该流加方式可降低H2O2对细胞的毒害作用，过氧化氢酶酶活达到29．89U／mL，与分批发酵相比提高了92．8％。     

重组大肠杆菌BL21（DE3）-pET28a（＋）-bgl诱导表达β-葡聚糖酶的条件优化

研究自行构建的产β-葡聚糖酶的工程菌E.coli BL21(DE3)-pET28a(+)-bgl在LB培养基中的生长特性,考察种子液的菌龄、培养基起始pH、接种量及诱导起始时发酵液菌浓度等对β-葡聚糖酶产生水平的影响;通过正交试验确定诱导剂IPTG及乳糖添加量、诱导温度及诱导剂作用时间.结果表明:培养基起始pH 7.0,对数生长中期的种子液(OD600为0.35)以接种量(体积分数)10%接入摇瓶发酵培养,37 ℃,200 r/min培养约3 h,菌液OD值达到1.0左右,添加终浓度分别为0.033 6 mmol/L的IPTG及10 mmol/L乳糖,24℃诱导6 h,发酵液清液中酶活达到最高(336.33 U/mL),菌体生长量为1.12 g/L,发酵液中总酶活达到459.32 U/mL,是原始菌株在相同条件下所产酶活的6.62倍.采用优化培养条件及诱导剂作用条件,重组菌在TB培养基中酶活水平进一步提高,诱导剂作用10 h,发酵清液中酶活为1 090.31 U/mL,总酶活1 570.83 U/mL,是原始菌在该条件下酶活的19.73倍,显示出重组菌具有广阔的工业化应用前景.     

中性蛋白酶芽孢杆菌BX-4产酶条件及部分酶学性质

采用稀释平板分离法从土壤中分离到一株产中性蛋白酶芽孢杆菌BX-4．通过单因素碳、氮源以及正交试验确定了最佳产酶培养基配方，同时还研究了起始pH值、金属离子、接种量对产酶的影响以及温度、pH值、金属离子以及表面活性剂对酶稳定性的影响；以最佳培养基为发酵培养基，于37℃、160r／min振荡培养48h，酶活达2519．35U／mL；该酶最适作用温度为55℃，最适作用PH值为7．5，在pH7．5缓冲体系中，55℃反应60min后仍有50％的酶活力，Ca^2＋和表面活性剂对酶有一定的激活作用，但激活作用不明显。     

胆固醇氧化酶发酵研究

对从土壤中筛选到的菌株ＤＧＣ－００７进行ＵＶ诱变,选育到菌株ＤＧＣ－０４８．对影响突变株产酶的条件进行了优化,初步确定了ＤＧＣ－０４８合适的产酶摇瓶培养基组成．在发酵温度为３０℃,培养基起始ｐＨ７．５～８．０的条件下,接种量１０％,发酵４８ｈ,产酶可达３５０μｍｏｌ／（ｍｉｎ·Ｌ）     

响应面法优化烯丙醇酮乙酸酯水解酶的产酶条件

采用响应面方法对一株能够选择性水解（R）-烯丙醇酮乙酸酯的菌株的发酵产酶培养基进行了优化。首先考察了不同碳、氮源的影响，在此基础上通过Plackett—Burman设计法时发酵培养基主要因子进行筛选，确定主要影响因子为橄榄油的质量浓度，黄豆饼的质量浓度和K2HPO4的质量浓度。用最陡爬坡实验逼近以上三因素最优水平，行用中心组合设计以及响应面分析确定主要影响因子的最佳浓度。在优化培养条件下，发酵液巾酶产量从94U／L提高到了358U／L，增加了281％。     

正交旋转回归试验优化纤维素酶发酵培养基

利用旋转回归法研究里氏木霉WX-112发酵生产纤维素酶的两个重要因素：微晶纤维素粉（Avicel）和麸皮对滤纸酶活的影响，并拟合出回归方程。经回归分析表明，培养基中Avicel、麸皮的含量及其配比对滤纸酶活有显著影响。通过岭脊分析寻优得出：Avicel最佳浓度为1．34g／dL、麸皮最佳浓度为3．35g／dL，在此优化条件下滤纸酶活可迭6．51U／mL。用30L发酵罐进行放大试验，滤纸酶涪可达10．84U／mL，CMCase达到449．57U／mL。     

半纤维素酶高产菌种的选育及产酶条件

以黑曲霉WA301为出发株,经过紫外诱变获得一株遗传性状稳定的半纤维素酶的高产突变株WA9024.通过对培养基中碳源、氮源、水分和起始pH值的优化,突变株WA9204以麸皮为基质的固态发酵产半纤维素酶的能力进一步得到提高.在较适的条件下,WA9024的甘露聚糖酶酶活达到8984U/g,木聚糖酶酶活达到503U/g,分别比出发菌株提高了1160%和210%.     

黑曲霉产α-转移葡萄糖苷酶固态发酵条件优化

摘要：对产α-转移葡萄糖苷酶的黑曲霉U菌株固态发酵条件进行了优化．结果表明：麸皮和水的质量比为1：1较好，35℃培养48h时产酶量及酶活较高；U菌株生长的最适pH值为6．0；麸皮中的碳源和氮源可以满足该菌株产酶的需要，可以不外加碳源和氮源．     

Variational Boundary Conditions for Molecular Dynamics Simulations of Solids at Low Temperature

Boundary conditions for molecular dynamics simulation of crystalline solids are considered with the objective of eliminating the reflection of phonons. A variational formalism is presented to construct boundary conditions that minimize total phonon reflection. Local boundary conditions that involve a few neighbors of the boundary atoms and limited number of time steps are found using the variational formalism. Their effects are studied and compared with other boundary conditions such as truncated exact boundary conditions or by appending border atoms where artificial damping forces are applied. In general it is found that, with the same cost or complexity, the variational boundary conditions perform much better than the truncated exact boundary conditions or by appending border atoms with empirical damping profiles. Practical issues of implementation are discussed for real crystals. Application to brittle fracture dynamics is illustrated.     

Ambulatory treatment of peptic ulcer by autologous transfusion of photo-modified blood

The authors have determined indications and contraindications for using the method of haemotherapy based upon their experience with more than 1200 transfusions of photomodified autoblood under conditions of the hospital and 84 AUVIBs under the ambulatory conditions. The treatment of non-complicated forms of ulcer disease of the stomach and duodenum is shown to be possible under the ambulatory conditions, cicatrization of the ulcers developing 2-3 times more rapidly than under the currently used treatment of the ulcer disease under conditions of the hospital.     

Classification of musculoskeletal spinal conditions*

The aim of this article is to present and discuss the classification of musculoskeletal spinal conditions. The major classifications presented are muscle, joint, and nerve root. Many different conditions are presented under each of these major classifications with emphasis on those conditions commonly seen in a physical therapy clinic. The clinical picture of each condition is presented showing the significant findings in the history, structural, mobility, neurological, and palpation exams. Treatment suggestions are presented to help clarify the differences between conditions, and to stress the importance of evaluation and classification before planning treatment. The author also stresses the interrelationship and progressive nature of certain conditions.J Orthop Sports Phys Ther 1979;1(1):3-15.     

负重对生物活性骨水泥与骨结合界面微力学及化学成分的影响

目的探讨负重对含锶羟基磷灰石(Sr-HA)生物活性骨水泥与骨结合界面微力学及化学成分的影响。方法12只兔随机分为两组,将Sr-HA活性骨水泥注入其中一组兔的髂骨内(非负重状态),另一组中,Sr-HA活性骨水泥被用于单侧半髋关节置换(负重状态)。术后6个月,我们分别对两种状态下骨与Sr-HA活性骨水泥界面的组织学、化学成分及力学特性等进行了研究和比较。结果组织学观察可见,在两种状态下,骨与Sr-HA活性骨水泥均能紧密结合。但负重组的骨-骨水泥界面可见活跃的新骨形成及骨的重建。能谱(EDX)分析的结果显示:负重组界面的钙与磷含量明显高于非负重组。此外,两种状态下,界面的力学性能表现出不同的特性:负重组界面的杨氏模量及硬度高于骨及骨水泥;而非负重组界面的力学性能介于骨与骨水泥之间。结论负重有利于骨的代谢及骨-骨水泥界面的力学特性。     

Stability of Finite Difference Discretizations of Multi-Physics Interface Conditions

We consider multi-physics computations where the Navier-Stokes equations of compressible fluid flow on some parts of the computational domain are coupled to the equations of elasticity on other parts of the computational domain. The different subdomains are separated by well-defined interfaces. We consider time accurate computations resolving all time scales. For such computations, explicit time stepping is very efficient. We address the issue of discrete interface conditions between the two domains of different physics that do not lead to instability, or to a significant reduction of the stable time step size. Finding such interface conditions is non-trivial.We discretize the problem with high order centered difference approximations with summation by parts boundary closure. We derive L²stable interface conditions for the linearized one dimensional discretized problem. Furthermore, we generalize the interface conditions to the full non-linear equations and numerically demonstrate their stable and accurate performance on a simple model problem. The energy stable interface conditions derived here through symmetrization of the equations contain the interface conditions derived through normal mode analysis by Banks and Sjögreen in [8] as a special case.     

Survival and function of hepatocytes on a novel three-dimensional synthetic biodegradable polymer scaffold with an intrinsic network of channels.

OBJECTIVE: To evaluate the survival and function of hepatocytes (HCs) on a novel three-dimensional (3D) synthetic biodegradable polymer scaffold with an intrinsic network of interconnected channels under continuous flow conditions. SUMMARY BACKGROUND DATA: The authors' laboratory has investigated HC transplantation using 3D biodegradable polymers as scaffolding as an alternative approach to treatment of end-stage liver disease. Previous studies have demonstrated survival of HCs transplanted on polymer discs in peripheral tissue sites and partial correction of single enzyme liver defects. One of the major limitations has been the insufficient survival of an adequate mass of transplanted cells; this is thought to be caused by inadequate oxygen diffusion. METHODS: HCs and nonparenchymal liver cells from Lewis rats were seeded onto 3D biodegradable polymer scaffolds. Microporous 3D polymers were created using 3D printing on copolymers of polylactide-coglycolide. The cell/polymer constructs were placed in static culture or continuous flow conditions. The devices were retrieved after 2 days and examined by scanning electron microscopy and histology. Culture medium was analyzed for albumin by enzyme-linked immunosorbent assay (ELISA). Differences in culture parameters including pH, PCO2, PO2, glucose, lactate, and HCO3 were examined. RESULTS: Scanning electron microscopy revealed successful attachment of HCs on the 3D polymer in both static and flow conditions. Histology demonstrated viable HCs in both conditions. ELISA demonstrated a significantly higher mean concentration of albumin in flow conditions than in static conditions. Culture parameter analysis revealed a significantly higher PO2 and glucose level, and a more physiologic pH in flow conditions than in static conditions. CONCLUSIONS: HCs cocultured with nonparenchymal cells can attach to and survive on the 3D polymer scaffolds in both static and flow conditions in the size and configuration used in this study. Flow conditions may provide a more conducive environment for HC metabolism and albumin synthesis than static conditions. The authors hypothesize that flow through directed channels will be necessary for the transfer of large masses of cells when implantation studies are initiated.     

Benign surgical diseases of the gastro-oesophageal junction

Benign surgical conditions of the oesophago-gastric junction (OGJ) are important causes of morbidity and in some cases mortality for patients. This chapter discusses both elective and emergency benign disorders of the OGJ, their investigation and management. Elective conditions include gastro-oesophageal reflux disease (GORD), giant para-oesophageal hiatal herniae (GPHH), achalasia and other motility disorders. These conditions are now usually all managed laparoscopically when operative intervention is required. Emergency conditions include acute presentations of giant para-oesophageal hiatal herniae and OGJ perforations including Boerhaave's syndrome. These conditions present diagnostic and management challenges to the surgeon and are associated with significant morbidity and mortality. Varices, gastro-intestinal stromal tumours (GISTs), ulcers and bleeding are not discussed in this article.     

Osmotic stress stimulates phosphorylation and cellular expression of heat shock proteins in rhesus macaque sperm

The cryosurvival of sperm requires cell signaling mechanisms to adapt to anisotonic conditions during the freezing and thawing process. Chaperone proteins heat shock protein 70 (HSP 70) and heat shock protein 90 (HSP 90; recently renamed HSPA and HSPC, respectively) facilitate some of these cell signaling events in somatic cells. Sperm were evaluated for their cellular expression and levels of phosphorylation of both HSP 70 and HSP 90 under anisotonic conditions as a potential model for cell signaling during the cryopreservation of macaque spermatozoa. In order to monitor the level of stress, the motility and viability parameters were evaluated at various time points. Cells were then either prepared for phosphoprotein enrichment or indirect immunocytochemistry. As controls, the phosphoserine, phosphothreonine, and phosphotyrosine levels were measured under capacitation and cryopreservation conditions and were compared with the phosphoprotein levels expressed under osmotic conditions. As expected, there was an increase in the level of tyrosine phosphorylation under capacitation and cryopreservation conditions. There was also a significant increase in the level of all phosphoproteins under hyperosmotic conditions. There was no change in the level of expression of HSP 70 or 90 under osmotic stress conditions as measured by Western blot. The enrichment of phosphoproteins followed by Western immunoblotting revealed an increase in the phosphorylation of HSP 70 but not HSP 90 under osmotic stress conditions. Indirect immunofluorescence localized HSP 70 to the postacrosomal region of sperm, and the level of membrane expression of HSP 70 was significantly affected by anisotonic conditions, as measured by flow cytometry. Taken together, these results suggest a differential role for HSP 70 and HSP 90 during osmotic stress conditions in rhesus macaque sperm.     

Intubating conditions and onset of neuromuscular block of rocuronium (Org 9426); a comparison with suxamethonium

The intubating conditions and neuromuscular blocking profile following 600 micrograms.kg-1 rocuronium (Org 9426) have been investigated in patients under various experimental conditions. They were compared with conditions following 1.5 mg.kg-1 suxamethonium, preceded by a precurarising dose (10 mg) of gallamine, and with those in a control group in the absence of a muscle relaxant. Rocuronium produced good to excellent intubating conditions at 60 as well as at 90 s after administration, even though there was only a partial blockade of the adductor pollicis muscle. Intubating conditions following suxamethonium were comparable with those after rocuronium. Half of the control patients could be intubated. The clinical duration and the recovery time of 600 micrograms.kg-1 of rocuronium were 24(4) and 9(3) min (mean(s.d.)), respectively. Rocuronium may have a major advantage over existing non-depolarising muscle relaxants due to the early presence of excellent intubating conditions. The results indicate that rocuronium may replace suxamethonium in procedures in which rapid sequence induction is required.     

后十字韧带完整性对股骨内髁生物力学特性的影响

 目的 探讨后十字韧带(posterior cruciate ligament, PCL)及其各分束的生物力学功能.以及 PCL完整性对股骨内髁生物力学特性的影响。方法 12具新鲜成人尸体膝关节标本在不同轴向载荷(0~800N)和不同屈曲角度(膝关节屈曲 0°、30°、60°和 90°)进行生物力学测试。PCL完整、前外侧束(anterolateral bundle.ALB)切断、后内侧束(posteromedial bundle,PMB)切断和 PCL完全切断顺序进行生物力学测试.分别测量加载后股骨内髁中部的应变。结果 0°位.各级载荷下 PMB切断和 PCL完全切断均引起股骨内髁应变增加.ALB切断对股骨内髁应变无明显影响.且在各级载荷下 PCL完全切断组股骨内髁的应变绝对值较 PMB切断组无明显增加。 30°、60°和 90°位.大载荷下 ALB切断和各级载荷下 PCL完全切断均引起股骨内髁应变增加.小载荷下ALB切断和各级载荷下PMB切断对股骨内髁应变无明显影响.且大部分载荷下 PCL完全切断组股骨内髁的应变绝对值较 ALB切断组明显增加。结论 在膝关节屈伸过程中 ALB和 PMB均有一定的稳定作用.伸直位 PMB对稳定起绝大部分作用.而屈曲位 ALB对稳定起大部分作用.且 PCL部分或完全断裂在屈伸过程中对股骨内髁均可产生不良的生物力学影响。