狼爪瓦松全草粗提物体外抑菌作用研究

[目的]研究狼爪瓦松(Orostachys cartilaginous A.Bor)全草粗提取物体外抑菌作用.[方法]采用液-液萃取法对狼爪瓦松的体积分数为0.75的丙酮提取液的活性成分进行初步分离,制备氯仿、乙酸乙酯、正丁醇及水相萃取物.采用滤纸片法和2倍连续稀释法测定了各相萃取物对4种供试菌的体外抑菌效果.[结果]狼爪瓦松全草体积分数为0.75的丙酮提取液的各萃取相对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌和普通变形杆菌有不同程度的抑菌活性,其中氯仿萃取相、乙酸乙酯萃取相对金黄色葡萄球菌显示了较好的抑菌效果,最低抑菌浓度均为1.25 mg/ml.[结论]中药狼爪瓦松全草的抑菌活性成分主要存在于氯仿萃取相和乙酸乙酯萃取相中,为狼爪瓦松抑菌药物的开发提供了理论依据.     

超声波辅助法提取甘草总黄酮工艺的研究

[目的]优化甘草中总黄酮的提取工艺.[方法]以乙醇为提取剂,采用超声波法辅助提取甘草中的总黄酮,并采用正交设计试验优化甘草总黄酮的提取工艺.[结果]在提取液乙醇浓度75%、料液比1:25、超声功率350 W,超声时间25 min的条件下,甘草总黄酮提取得率最高达1.943%,各因素影响顺序为乙醇浓度>料液比>超声功率>超声时间.[结论]该试验为甘草的进一步开发利用提供了科学依据.     

牛蒡抗氧化成分提取工艺的优化及性能测定

[目的]优化牛蒡抗氧化成分的提取工艺,并对其抗氧化性能进行测定.[方法]采用正交试验对其提取工艺进行优化:采用常规方法测定牛蒡提取物对超氧阴离子自由基和羟基自由基的清除率.[结果]牛蒡抗氧化成分最佳提取工艺条件为:料液比1:20,乙醇浓度100%,提取时间为1.5 h,提取温度70℃.牛蒡提取液清除超氧阴离子自由基和羟基自由基的能力随着浓度的增加而增强,且牛蒡乙醇提取液清除自由基能力强于牛蒡水提液.牛蒡提取液的主要成分为绿原酸.[结论]该研究为牛蒡提取物在食品和医药行业的应用提供了科学依据.     

高原"加拿大"燕麦中皂甙提取工艺研究

[目的]研究利用索氏浸提法提取燕麦中皂甙工艺条件.[方法]以乙醇-正丁醇为溶剂,以皂甙RC为标准品,采用分光光度法定量分析燕麦提取液中总皂甙含量,采用正交试验研究料液比、乙醇浓度、浸提温度对提取率的影响.[结果]最佳提取条件为料液比1:7,乙醇浓度80%,浸提温度60 ℃,提取率为2.024%;各因素影响主次顺序为乙醇浓度＞浸提温度＞料液比.[结论]该方法操作方便,简单易行,具有推广应用价值.     

"青海444"燕麦中皂苷提取工艺研究

[目的]研究利用索氏浸提法提取燕麦中皂苷的工艺条件.[方法]以乙醇–正丁醇为溶剂,以皂苷Re为标准品,采用分光光度法定量分析燕麦提取液中总皂苷含量,利用正交试验设计研究料液比、乙醇浓度、浸提温度对提取率的影响.[结果]各因素对皂苷提取率影响的主次顺序依次为:乙醇浓度>料液比>浸提温度;最佳提取条件:料液比为1∶7,乙醇浓度70%,浸提温度60 ℃;在此条件下,提取率为2.504%.[结论]该方法操作方便,简单易行,具有推广应用价值.     

超声波辅助提取苹果皮中果胶的研究

[目的]探讨采用超声波辅助提取苹果皮中果胶的工艺条件.[方法]采用超声波辐射革取法从苹果皮中提取了果胶,并采用单因素试验研究了不同萃取剂、溶剂、超声时间、超声波辐射功率、料液比、乙醇浓度及提取液pH值对果胶提取率的影响.[结果]确立了超声波条件下提取果胶的最佳工艺条件为:用盐酸调pH值为1.8,用水作为溶剂,料液比为1:20,超声波功率为600 W,超声波辐射时间为40min,乙醇浓度为60%.谊工艺条件下,果胶提取率可达12.9%.[结论]为综合利用资源及利用超声波提取苹果皮中果胶提供了一条可行性途径.     

南山茶茶籽多酚的提取及测定

[目的]研究南山茶籽饼粕中多酚类物质的提取及测定.[方法]采用L9(34)正交试验设计,研究了不同的料液比、提取时间、乙醇浓度和提取温度对多酚提取率的影响.[结果]最优浸提南山茶籽饼粕多酚工艺条件为:40%乙醇浓度、提取时间2 h、提取温度65 ℃、料液比1∶25.该条件下的多酚含量达到了3.5%,对植物病原真菌(炭疽菌)菌丝生长具有明显的抑制作用.[结论]该研究为南山茶籽饼粕的开发利用提供了理论依据.     

西归黄酮体外抗氧化活性的研究

[目的]研究西归黄酮体外抗氧化活性.[方法]分别采用水杨酸比色法、邻苯三酚自氧化法和DPPH法测定和评价西归黄酮体外抗氧化的效果, 以抗坏血酸作为对照.[结果]西归黄酮能较好地清除羟自由基、超氧阴离子自由基和DPPH自由基.[结论]西归黄酮具有较好的体外抗氧化活性.     

紫茎泽兰不同组织水提取液对水稻·玉米化感作用机制

[目的]研究紫茎泽兰不同组织根、茎、叶水浸提取液对2种农作物玉米、水稻化感作用及对受试农作物生理指标的影响,以探讨化感物质作用机制.[方法]采用培养皿滤纸法测定不同浓度根、茎、叶水浸提液对受试种子萌发率和幼苗生长影响,并检测受试农作物生理指标丙二醛(MDA)含量、过氧化物酶(POD)活力的变化.[结果]紫茎泽兰根、茎、叶水浸提液对受试玉米、水稻的发芽率和幼苗根长、株高均有不同程度的影响,使受试农作物幼苗体内丙二醛(MDA)含量增加、过氧化物酶(POD)活性呈现先增加后降低趋势.[结论]紫茎泽兰不同组织水提液对受体植物的种子萌发、幼苗生长过程均具有明显的抑制作用,其茎的化感敏感效应大于根、叶,水提液抑制受试农作物光合效率,提高了幼苗体内的MDA含量,并降低了POD酶活性.     

宁夏沙枣中总黄酮的提取工艺研究

[目的]优化宁夏沙枣中总黄酮的提取工艺.[方法]采用乙醇回流法对沙枣中的总黄酮进行提取.在单因素试验的基础上,采用正交设计考察提取温度、乙醇浓度、提取时间和料液比对黄酮提取率的影响.[结果]最佳工艺条件如下:提取温度80℃,提取时间1h,提取剂为体积分数0.60的乙醇,料液比1:18.在此条件下,宁夏沙枣中总黄酮的提取率可达3.070 mg/g.[结论]该研究为提高宁夏沙枣的药用功效和进一步开发利用提供了试验依据.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.