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91.
作者利用交流电弧和光栅摄谱仪组装了能够绘制谱线轮廓曲线和准确测定谱线宽度的记录仪,用线宽增量法对生物材料(拟血清)中的主要成分Ca和微量元素Cu进行了测定。与黑度法相比,本实验结果的线性好,误差小,再现性有所提高。这些结果表明,用上述仪器装置和线宽增量法进行生物材料含量分析优于黑度法。 相似文献
92.
标记抗原在贮存过程中,由于受幅射分解和脱碘影响而使免疫活性和生物活性降低。我们对自制的~(125)碘-绒毛膜促性腺激素进行了实验观察。结果显示:贮存1月后,其免疫活性和生物活性分别降低了33.1%和44.0%;经电泳纯化后的标记物的免疫活性和生物活性明显提高,分别达到了最初的90.5%和95.3%。 相似文献
93.
When the distance between linked loci is expressed in terms of the correlation between the identity-by-descent (idb) values of the loci, then a path model may be used to order loci with data on sib-pairs and their parents. The relationship between the recombination fraction and the correlation coefficient is developed and a method for fitting a covariance matrix predicted by a specific ordering of loci to an observed covariance matrix is proposed. © 1993 Wiley-Liss. Inc. 相似文献
94.
蜂胶提取物对小鼠胸腺肽合成的影响 总被引:2,自引:0,他引:2
目的:研究蜂胶乙醇提取物黄酮(EEP)对小白鼠衰老过程中胸腺肽合成量的影响。方法:垂直板电泳法。结果:EEP可增加小鼠胸腺肽的合成量。结论:EEP可增强小鼠的免疫力。具有抗衰老作用。 相似文献
95.
Abstract – Though the use of mouthguards (MGs) has increased with the increase in sporting activities, little is known about the influence of their fabrication methods on longitudinal dimensional stability. The objective of this study was to compare the difference in the longitudinal dimensional stability between single and laminated MGs. Single-layer MGs were made from a 4.0 mm thick ethylene vinyl acetate (EVA) sheet and laminated MGs were made from two 2.0 mm thick sheets of EVA. MGs were kept in a 37°C water bath for 60 h, equivalent to the time period of 3-months inter-oral use. MG deformation was analyzed by measuring designated points on the MG border using a profile projector (J-12, Nikon Inc., Tokyo, Japan) before and after the water immersion. A finite-element model was also created to examine the time course of stress accumulation during the sheet forming process using Finite Element software. Longitudinal deformation was smaller in the laminated MGs than in the single-layer MGs in the anterior area ( P < 0.05). Finite element method (FEM) analysis also showed the largest stress accumulation in the anterior incisal area where deformations were mainly observed. Laminated double layer MGs have advantages over single-layer MGs in terms of longitudinal stability due to lower stress accumulation during the fabrication process. 相似文献
96.
目的:探讨膀胱肿瘤及癌旁组织端粒酶活性表达及临床意义。方法:以改良TRAP法测定91例膀胱癌组织标本端粒酶活性表达。结果:83例膀胱移行细胞癌组织中78例检出端粒酶活性。阳性率为94%,其对应的癌旁组织也有14%的检出率,8例膀胱乳头状瘤组织中4例检出端粒酶活性,阳性率为50%,其对应的癌旁组织检出率为12%,端粒酶活性在不同临床病理类型的膀胱肿瘤及癌旁组织中表达无显差异(P>0.05),结论:应用非放射性的银染方法对端粒酶的活性进行检测,图像清晰,简便,安全,易于临床推广。 相似文献
97.
The measurement of amniotic fluid (AF) acetylcholinesterase isoenzyme (AChEI) is a relatively new method for early diagnosis of open neural tube defects (NTDs). As quantitative methods are of unproven reliability at present, the authors used a high resolving power qualitative method-vertical slab polyaerylamide gel electrophoresis. The benefits of this technique are: simplicity of operation, accuracy, unsophisticated equipment, and easily available reagents. Combined results of 9 NTDs studies revealed that samples from early pregnancy gave more accurate results than those from late pregnancy. 相似文献
98.
胆石症是一种常见病,鹅去氧胆酸(CDCA)可用于胆固醇胆石症的治疗。它能改变胆汁组成,降低胆汁内胆固醇饱和度,增加胆固醇溶解性,使胆石逐渐溶解。但CDCA易被肠道内细菌7-脱羟酶作用生成石胆酸(LC),引起腹泄、腹部痉挛、高转 相似文献
99.
医疗设备投资决策的敏感性分析研究 总被引:2,自引:1,他引:1
不恰当的医疗设备投资对医院及患者的利益均会造成损失,因此,在投资决策前进行严谨科学地可行性评估十分必要。通过对净现值的敏感性分析,医院的决策者可以了解各种不确定因素对投资方案经济效果的影响程度,以及投资方案对外部条件变化的承受能力,从而掌握风险条件下正确的决策原则和决策方法。 相似文献
100.
C Piérard-Franchimont P Paquet P Quatresooz GE Piérard 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):657-661
BACKGROUND: The observation of photo-exposed skin under ultraviolet light reveals a mosaic pattern of varying intensity in epidermal melanization. Several patterns of mosaic subclinical melanoderma (MSM) have been described using a specially designed CCD camera and the ultraviolet light-enhanced visualization (ULEV) method. Vitamin D(3) and its analogues influence the biology of keratinocytes and melanocytes. OBJECTIVE: To assess the effect of calcipotriol on MSM. METHODS: This randomized split-face study was conducted in 27 men to compare the effect of once daily applications of 5% calcipotriol cream or a moisturizing cream on the heterogeneity of facial MSM. Computerized image analysis of video images was used at 1-month intervals before and during a 2-month treatment, as well as during a 3-month follow-up. RESULTS: At both sites, the average melanin content of the epidermis showed no significant change over time. However, the mottled appearance was smoothened at the calcipotriol site, whereas it was increased at the site receiving the moisturizer. CONCLUSION: The decreased heterogeneity in MSM after calcipotriol applications suggests a control of the epidermal melanocyte unit by the vitamin D(3) derivative. 相似文献