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101.
对用酵母转化木糖醇中工业化原料培养基组成的优化进行了较系统的研究,研究中采用了Plackett-Burman[1]和响应曲面法,得到了一个完全用工业化原料组成的优化培养基,摇瓶转化率最高达80.4%。实验结果表明,在保持较高转化率的前提下,发酵培养基可以采用较廉价的工业化原料。 相似文献
102.
Clinical experimental study of Arnebia root oil promoting histological change and up-regulating bFGF expression in the wound 总被引:1,自引:0,他引:1
Objective: To explore the molecular biological mechanism of Arnebia root oil promoting wound surface healing by observing histological change and bFGF expression in wound surface tissue as well as wound surface healing rate. Methods: Raw surface in patients were randomly divided into 2 groups. Experimental group was treated by Arnebia root oil and control group was treated by petrolatum gauze, then the tissular structure of raw surface was observed by histology, histochemistry, electron microscope and raw surface healing rates was compared either, bFGF expression in wound surface tissue was also evaluated by Western-blot. Results: Raw surface healing rate of experimental group and control group had obvious difference(P〈0.05). Raw surface of experimental group had more fibroblast, collagen and blood capillary, bFGF was expressed in both groups, and the level of bFGF expression in experimental group was higher than that in control group in every period. There were significant differences between 2 groups in gray-density value ( P〈0. 05). Being as an internal control, no significant change was found for β-actin expression, although it occured in various phases. Conclusion: Arnebia root oil plays an important regulative role in the course of healing of wound and it can promote skin raw surface repair and accelerate wound surface healing, which are caused by enhancing bFGF in the wound tissue. 相似文献
103.
John Waititu Muritu Isaac Ongubo Kibwage Charles Karimi Maitai Jos Hoogmartens 《Journal of pharmaceutical and biomedical analysis》1994,12(12):1483-1488
Contents of tetracycline, its degradation products (epitetracycline, epianhydrotetracycline, anhydrotetracycline) and a fermentation impurity (2-acetyl-2-decarboxamidotetracycline) were determined in four raw materials, 12 batches of six ointment products, four eye ointment products and nine batches of five capsule products, all sampled from the Kenyan market. The analytical method was liquid chromatography on a column packed with a poly(styrenedivinylbenzene) material (8-μm PLRP-S 100 Å). All raw materials and finished products had tetracycline contents and impurity levels within the prescribed compendial limits. 相似文献
104.
HFTJV对蒸气吸入性损伤犬血气的影响 总被引:1,自引:0,他引:1
采用本地健康杂种犬15条,分成对照组(6条)和正反双向喷射通气(HFTJV)治疗组(9条)二组,用蒸气吸入方法使犬严重致伤,随后分析损伤犬的血气变化及HFTJV对其的影响。结果表明:损伤犬皆迅速呈现Ⅱ型呼吸衰竭改变;HFTJV对维持严重蒸所吸入性损伤犬血气的正常有显著作用;在需要改善严重缺O2状态同时又要加强CO2排出时,HFTJV有独到之处。 相似文献
105.
根据甘遂的传统应用,并以其引起家兔离体结肠收缩和收缩强度为指标,把生甘遂与制甘遂对乙醇取物进行药理观察。结果表明:生甘遂经炮制以后其作用强度和毒性都有明显减低。 相似文献
106.
107.
Thomas F. Mancuso 《American journal of industrial medicine》1983,4(4):501-513
The first phase of the exploration of occupation-related cancer among machinists was a retrospective review of deaths among members of the International Association of Machinists and Aerospace Workers in 1973, in which mesotheliomas were identified in workers in railroad and other industries. The second phase of the study initiated in 1982 was the establishment of a cohort study of machinists, employed for railroad company A, who were alive in January 1954. The cohort consisted of 197 machinists who had been employed by the same railroad prior to 1935 and observed to 1982. Causes of death were identified for 132 of the cohort. There were 18 alive and 47 not traced. Among the 29 cancer deaths, there were nine mesotheliomas and one endothelioma of the pleura. Additional retrospective surveys of deaths among members of the railroad lodges of the international union, together with the cohort study, identified a total of 42 mesotheliomas, two endotheliomas of the pleura, and two cancers of the pleura among former railroad machinists. Among the machinists employed in other industries, 16 mesotheliomas and six cancers of the pleura were identified. For decades, machinists, by the nature of their craft, have had a high risk of occupation-related cancer due to asbestos exposure. 相似文献
108.
In vivo NMR experiments are performed to determine the degree of spin labeling for measurement of tissue perfusion by NMR using spin labeling of arterial water by adiabatic fast passage. Arterial water spins are labeled using flow in the presence of a field gradient and B1 irradiation to fulfill the conditions for adiabatic fast passage spin inversion. It is demonstrated that the NMR-measured tissue perfusion is not affected by changing the degree of spin labeling as long as the degree of spin labeling is determined and accounted for according to the model used for calculating perfusion. By measuring the degree of spin labeling with different arterial blood flow velocities induced by different arterial pCO2, it is also demonstrated that, when spin labeling is carried out by adiabatic fast passage, the degree of spin labeling is not affected by changes in arterial blood flow velocity over a broad range. 相似文献
109.
黄秀丽 《国际医药卫生导报》2010,16(6):689-691
目的 分析手术钳类蒸汽快速灭菌效果的影响因素并给出相应对策。方法对带有轴节部位的手术器械进行强化生物监测,分别对两组手术钳进行细菌采样培养并且对比实验结果。结果在生物监测符合要求的情况下,未打开轴节的手术钳细菌采样培养阳性不合格率达到15%。结论应重视压力蒸汽快速灭菌的规范操作和关注重点注意事项尤其是手术器械的轴节部位,对于手术钳、剪类器械需进行细菌采样培养来强化生物监测效果。 相似文献
110.
目的:建立检查头孢他啶原料药中有关物质的方法。方法:采用高效液相色谱法。色谱柱为ApolloCm以磷酸盐缓冲溶液(pH3.4)和乙腈分别为流动相A和流动相B,梯度洗脱,检测波长为254nm,流速为1.1ml/min,柱温为45oC;同时与《中国药典》方法比较检查结果。结果:本方法可分离出头孢他啶的11个相关杂质,分析时间约为30rain,出峰均匀且各峰间分离度良好,检测限为0.4ng;《中国药典》方法可分离出10个杂质,主峰前各杂质分离度不好,分析时间为55min左右。结论:与《中国药典》方法比较,本方法具有分离杂质多、分离度好、分析时间短的优点,可作为头孢他啶原料药中有关物质的分析方法。 相似文献