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101.
S Gorman N Viseshakul B Cohen S Hardy GA Grant CS Yost JR Forsayeth 《Canadian Metallurgical Quarterly》1997,44(1):143-146
The purpose of this investigation was to develop a method that could be used to estimate how damaging sodium ethoxide is to different antigens with respect to immunolabeling when epoxy sections are deplasticized. If we obtain weak labeling for an antigen on deplasticized epoxy sections, this might be caused by the damaging effect of the ethoxide solution. It is therefore interesting to develop a method to check if this really is the reason. Fibrin clots and tissues of human kidney and thyroid were embedded in LR White resin. Some thin sections from these specimen blocks were exposed to sodium ethoxide in the same way as epoxy sections are when being deplasticized. Other sections from the same blocks were not exposed to sodium ethoxide. Both categories of sections were immunogold-labeled with anti-fibrinogen, anti-thyroglobulin, anti-IgA, anti-IgG, or anti-IgM. The intensity of immunolabeling of sections treated with ethoxide was compared with the immunolabeling of corresponding sections that were not treated with ethoxide. No significant differences were found in immunolabeling for fibrinogen, IgA, IgG, and IgM. For thyroglobulin, the intensity was approximately 30% less in tissues that were exposed to sodium ethoxide. The practical significance of this method is that we easily can examine the degree to which a given antigen is affected by sodium ethoxide, which is the agent used for deplasticizing epoxy sections. 相似文献
102.
CS Butler HE Seward C Greenwood AJ Thomson 《Canadian Metallurgical Quarterly》1997,36(51):16259-16266
The reaction of nitric oxide (NO) with fast cytochrome bo from Escherichia coli has been studied by electronic absorption, MCD, and EPR spectroscopy. Titration of the enzyme with NO showed the formation of two distinct species, consistent with NO binding stoichiometries of 1:1 and 2:1 with observed dissociation constants at pH 7.5 of approximately 2.3 x 10(-)6 and 3.3 x 10(-)5 M. Monitoring the titration by EPR spectroscopy revealed that the broad EPR signals at g approximately 7.3, 3.7, and 2.8 due to magnetic interaction between high-spin heme o (S = 5/2) and CuBII (S = 1/2) are lost. A high-spin heme o signal at g = 6.0 appears as the 1:1 complex is formed but is lost again on formation of the 2:1 complex, which is EPR silent. The absorption spectrum shows that heme o remains in the high-spin FeIII state throughout the titration. These results are consistent with the binding of up to two NO molecules at CuBII. This has been confirmed by studies with the Cl- adduct of fast cytochrome bo. MCD evidence shows that heme o remains ligated by histidine and water. Addition of excess NO to the Cl- adduct leads to the appearance of a high-spin FeIII heme EPR signal. Hence chloride ion binds to CuB, blocking the binding of a second NO molecule. These results suggest a mechanism for the reduction of NO to nitrous oxide by cytochrome bo and cytochrome c oxidase in which the binding of two cis NO molecules at CuB permits the formation of an N-N bond and the abstraction of oxygen by the heme group. 相似文献
103.
当机械设备发生故障时,厌氧螺纹锁固剂便可发挥作用。正如赛车的特滑层有助于确保车辆在赛道的抓地力,螺纹锁固剂有助于保证紧固件螺纹的夹持力。根据厌氧技术,这些金属胶粘剂可以实现机械辅助措施无法实现的功能:它们可完全填满连接螺纹之间的微小间隙。使用螺纹锁固剂固定的螺栓可以提供比机械装置更好的夹紧力。专用螺母或垫圈的价格是液体螺纹锁固剂的5倍以上。采用液体螺纹锁固剂可降低库存成本。在选择螺纹锁固复合物时,有一些关键因素需要考虑:抗剪强度、固化速度、间隙填充能力和工作环境。 相似文献
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Justification of early treatment of nocturnal enuresis is founded in the negative psychological impact on the child. In fact nocturnal enuresis delays early autonomy and socialisation by decreasing in self-esteem and self-confidence. Nocturnal enuresis classification is the preliminary step to correct therapy. Enuresis must be classified as primary (never acquired nocturnal control) or secondary (at least 6 months of dry nights). A child is also classified as having monosymptomatic enuresis if she/he experienced only night wetting and symptomatic enuresis if she/he experienced night wetting associated with diurnal voiding symptoms (urinated > or = 7 times a day, urgency, damp pants, squatting, holding the perineum, sitting on one heel). Monosymptomatic patients must be treated with desmopressin nasal spray at the daily dose of 20 micrograms at bed time. If the reduction of at least the 50% of the basal number of the wet nights is not achieved, the dosage must be increased until 40 micrograms. For patients affected by rhinitis or asthma, desmopressin is now available in tablets. In symptomatic patients desmopressin therapy must be associated to oxybutinin (5 mg x 2). Therapy interruption must be gradual with desmopressin reduction of 10 micrograms every 30 days. In symptomatic patients oxybutinin must be introduced only at bed time. The efficacy of the drugs depends on the therapy length. The highest percentage of success is obtained if the treatment is protracted for at least six months. Antidepressants are also used for nocturnal enuresis especially imipramine. The dosage varies between 0.5-1.5 mg/ kg/daily. As plasmatic levels are achieved only in 30% of treated patients, a 3-5 fold increase in suggested. Nevertheless these levels result in near toxic threshold concentration. Sporadic treatment purposes include amytriptiline, diclofenac sodicum, viloxsazine and methilphenidate if giggle incontinence is present. Non responders may be treated with alarm. If after 16 weeks of treatment no success is obtained alarm use must be interrupted. 相似文献
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109.
Roth Philip L.; Van Iddekinge Chad H.; Huffcutt Allen I.; Eidson Carl E. Jr.; Bobko Philip 《Canadian Metallurgical Quarterly》2002,87(2):369
Previous studies of standardized ethnic group differences in the employment interview have shown differences to be relatively small. Unfortunately, many researchers conducting interview studies have not considered the issue of range restriction in research design. This omission is likely to lead to underestimates of standardized ethnic group differences (d) when the interview is considered as an initial screening device or used in combination with other initial screening devices. The authors found that 2 forms of a behavioral interview were associated with standardized ethnic group differences of .36 and .56 when corrected for range restriction. These differences are substantially larger than previously thought and demonstrate the importance of considering a variety of study design characteristics in obtaining the appropriate parameter estimates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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