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1.
Kristina M. Obom Andrew Magno Patrick J. Cummings 《Journal of visualized experiments : JoVE》2013,(79)
Fermentation systems are used to provide an optimal growth environment for many different types of cell cultures. The ability afforded by fermentors to carefully control temperature, pH, and dissolved oxygen concentrations in particular makes them essential to efficient large scale growth and expression of fermentation products. This video will briefly describe the advantages of the fermentor over the shake flask. It will also identify key components of a typical benchtop fermentation system and give basic instruction on setup of the vessel and calibration of its probes. The viewer will be familiarized with the sterilization process and shown how to inoculate the growth medium in the vessel with culture. Basic concepts of operation, sampling, and harvesting will also be demonstrated. Simple data analysis and system cleanup will also be discussed. 相似文献
2.
John W. Brown 《Journal of experimental marine biology and ecology》1984,80(2):197-206
The classification of lysine biosynthetic pathways in various organisms have been used to investigate their descent in evolution. We have attempted these determinations in the diatoms Amphora coffeaeformis var:perpusilla (Grunow Cleve.) and Phaeodactylum tricornutum (Bohlin). Additionally, we have verified earlier results of Vogel in a green alga, Chlorella pyrenoidosa strain Tx 71105 (Texas Culture Collection). Our research indicates that the diaminopimelic acid route is involved in all three organisms. While these studies do not exclude the possible co-existence of the α-aminoadipic acid route, the results imply a closer evolutionary relationship of pennate diatoms to bacteria and “classical” photosynthetic plants rather than to heterotrophic or mixotrophic fungi and atypical algal strains such as the Euglenophyta. 相似文献
3.
Geok -Yong Tan Wai -Koon Tan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(2):258-264
Summary Quantitative inheritance of resistance to Phytophthora pod rot (Ppr) was studied in cocoa hybrid progeny from 12 Trinitario x Amazonian crosses and their reciprocal crosses. The crossing scheme was similar to a factorial design. Disease was assessed by the number and percentage of infected pods on each tree. Highly significant differences due to general combining abilities (GCA) were obtained for all characters, except for the GCA of Trinitario on total pod production. Differences for specific combining ability (SCA) were not significant for all characters. There were no significant differences between reciprocal crosses. The Trinitario clone K82 provided the only source for the hybrid progenies of strong Ppr resistance to the hybrid progenies, while K20 provided moderate resistance. Other parental clones — KA2-101, KA5-201, KEE 2, KEE 5, and KEE 52 — produced progenies which were susceptible to Ppr. It is evident that resistance to Ppr in cocoa is inherited additively. Maternal and cytoplasmic effects were assumed to have no influence on inheritance of resistance. It is also concluded that resistance to Ppr of the kind shown by K82 is likely to be horizontal resistance. Breeding for high-yielding cultivars combined with Ppr resistance is the most effective way of controlling Ppr of cocoa on the crops of growers with small holdings in Papua New Guinea. 相似文献
4.
摘要 目的:探讨七氟醚联合瑞芬太尼维持麻醉对介入治疗颅内动脉瘤(IA)患者神经功能、认知功能及炎性因子的影响。方法:选入2020年1月~2022年6月在我院接受介入手术治疗的IA患者80例,根据麻醉方式不同分为A组(七氟醚联合瑞芬太尼)和B组(丙泊酚联合瑞芬太尼),每组40例。评价两组患者的神经功能、认知功能、炎症因子水平等指标,并进行统计比较。结果:A组T1~T3时心率(HR)和平均动脉压(MAP)明显优于B组(P<0.05);A组术后24 h和术后7 d美国国立卫生研究院卒中量表(NIHSS)评分明显低于B组(P<0.05),易智能精神状态检查量表(MMSE)评分显著高于B组(P<0.05);A组术后24 h、术后3 d血清肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)和白细胞介素-6(IL-6)水平均明显低于B组(P<0.05);A组术后自主呼吸恢复时间、苏醒时间、拔管时间及拔管后躁动发生率较B组低(P<0.05);不良反应无差异(P>0.05)。结论:将七氟醚联合瑞芬太尼维持麻醉应用于介入治疗IA患者,可平稳血流动力学,改善术后神经功能及认知功能,降低炎症反应,提高麻醉苏醒质量。 相似文献
5.
摘要 目的:研究丙泊酚联合七氟醚麻醉在先天性心脏病介入手术患儿中的心肌保护作用及对苏醒质量和应激反应的影响。方法:选择2020年1月~2022年4月期间在苏州大学附属儿童医院接受先天性心脏病介入手术患儿96例,按照双色球法将患儿分为对照组(n=48,接受瑞芬太尼、丙泊酚麻醉)和观察组(n=48,接受丙泊酚、七氟醚麻醉)。对比两组患儿心率、呼吸频率、平均动脉压、苏醒质量、心肌损伤指标、应激反应指标和不良反应发生率。结果:两组置喉罩时(T1)~拔除喉罩(T4)时间点心率、呼吸频率、平均动脉压下降后升高,观察组高于对照组同时间点(P<0.05)。观察组的苏醒时间、拔管时间均短于对照组(P<0.05)。两组术毕、术后24 h肌酸磷酸激酶同工酶(CK-MB)、心肌肌钙蛋白(cTnI)升高后下降,观察组低于对照组同时间点(P<0.05)。两组术毕、术后24 h血糖、皮质醇升高后下降,观察组低于对照组同时间点(P<0.05)。两组不良反应发生率组间对比,差异不显著(P>0.05)。结论:丙泊酚联合七氟醚麻醉应用于先天性心脏病介入手术中,可减轻患儿的应激反应,稳定机体血流动力学波动,同时还可发挥心肌保护作用,提高苏醒质量。 相似文献
6.
Most cells have a morphological polarity with the centrioles and Golgi apparatus occupying one pole of the cell and the nucleus the other. This structural polarity often correlates with functional polarity as in secretory epithelia where the Golgi apparatus moves to the pole of the cell from which secretory materials are exreted. In limb development an interaction of unknown mechanism occurs between the epithelium and mesenchyme. We have evaluated the pattern of cell polarity using silver impregnation of the Golgi apparatus in limb epithelium and mesenchyme of mouse embryos from day 9.5, when limbs are first visible, to day 15, when cartilage formation is complete. Cells in the epithelium almost always have the Golgi apparatus in the apex of the cell, i.e., oriented away from the basement membrane. The layer of mesenchyme cells just beneath the basement membrane initially has only 16 to 25% of the cells oriented toward the basement membrane. A marked shift in orientation occurs between days 12 and 13 so that from days 13 to 15 up to 53% of the mesenchyme cells are oriented toward the basement membrane. This shift in orientation occurs more slowly in the mesenchyme at a depth of four cells below the basement membrane. This changing pattern of mesenchymal cell polarity occurs at a time when there is an apparent increase in the amount of extracellular matrix, especially in the region just below the basement membrane. 相似文献
7.
K. K. Wu D. J. Heinz H. K. Meyer S. L. Ladd 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,56(6):241-244
Summary Five Hawaiian commercial sugarcane (Saccharum sp. hybrids) clones were crossed in a full diallel. Four morphological characters were studied in the progeny: number of millable stalks per plant, stalk diameter, stalk length, and sucrose content. A fifth character, plant volume, was calculated from stalk number, stalk diameter and stalk length. The five selected parental clones were treated as fixed variables in the analysis. General combining ability (gca) was significant for all five characters; specific combining ability (sca) was significant for stalk diameter, stalk length, and plant volume. The variance for gca was large in all progeny populations. However, the variance for sca was large in the progeny of only some clones and/or for some individual characters. Parents were evaluated on the basis of their general combining ability: clone H49-3533 had high gca for sucrose content, while clone H53-5356 had high gca for plant vigor.Published with the approval of the Director as Journal Series Paper No. 455, Experiment Station, Hawaiian Sugar Planters' Association. 相似文献
8.
Heat-derived (60°C) extracts of Limulus amoebocyte lysate (LAL) were found to contain potent “broad-spectrum” antimicrobial activity. Additional heating of the LAL extracts to 100°C for 30 min completely inactivated the antimicrobial activity and served as a control. Antimicrobial activity was observed over a temperature range of 0° to 37°C (higher temperatures not tested) with greatest activity at 37°C. Antimicrobial activity of LAL extracts was variable when tested against Gram-negative bacteria of the family Enterobacteriaceae. A twofold concentration of the extracts resulted in a significant decrease in antimicrobial effectiveness. Dialysis of single- and double-strength LAL extracts against deionized water produced a marked and significant enhancement of antimicrobial activity against both resistant and sensitive species, confirming the presence of a dialyzable inhibitor(s). Dialyzed LAL extracts were active against 13 of 14 species of Enterobacteriaceae tested. Two strains of Pseudomonas aeruginosa were susceptible as were two of three Gram-positive cocci tested. Highly sensitive bacterial species were rapidly killed with a greater than 90% reduction in viable counts occurring within the first 30 min of reaction time. Dialyzed LAL extracts also possessed considerable antifungal activity. The role of the Limulus polyphemus amoebocyte in defense against microbial invasion and dissemination is discussed. 相似文献
9.
Randall M. Zusman M.D. Lloyd Axelrod M.D. Nina Tolkoff-Rubin M.D. 《Prostaglandins & other lipid mediators》1977,13(5):819-830
Three patients with the hepatorenal syndrome were treated with prostaglandin E1 administered through a selective renal arterial catheter. Prostaglandin E1 was given in progressively increasing doses (2 to 100 ng/kg/min) over a 60-minute period. Control plasma prostaglandin E levels were elevated in all three patients, 0.98, 0.91, and 0.83 ng/ml, respectively. At the end of the infusion, plasma prostaglandin E levels had risen to 10.4, 2.63, and 10.3 ng/ml in the three patients respectively. Plasma renin activity increased during the course of the infusion in two of the patients. The plasma aldosterone concentration did not change during the prostaglandin E1 infusion. Intrarenal prostaglandin E1 failed to increase urine volume or urinary sodium concentration in three patients with the hepatorenal syndrome. 相似文献
10.