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排序方式: 共有1112条查询结果,搜索用时 15 毫秒
1.
血液分析仪红细胞指数质控方法的探讨 总被引:3,自引:1,他引:2
目的 探讨血液分析仪红细胞指数的质控方法。方法 利用L-J质控空图和某全血质控物提供的有关数据,推理论证红细胞指数[MCV、MCH、MCHC]在控时对其有关测定参数值的新的质控要求。结果 红细胞指数有关测定参数值的质控范围应分别为HGB:(?)±1.7 s,HCT:(?)±1.06 s,RBC:(?)±1.06s。超出此范围判定为失控。结论 执行该质控判定标准可以实现对红细胞指数实施质控的目的。 相似文献
2.
黄疸乳糜对血液细胞分析结果的影响 总被引:1,自引:0,他引:1
目的:探讨黄疸、乳糜对血液细胞分析结果的影响。方法:制备含一定浓度梯度胆红素、甘油三酯的全血标本,在血细胞分析仪上进行测定,同时对临床乳糜标本加以检测。结果:黄疸标本分析结果中血小板计数降低,与胆红素浓度呈负相关,相关系数为-0.9925;当胆红素≥547.2μmol/L时,血红蛋白测定受干扰。而乳糜标本的分析结果中,血红蛋白浓度假性增高,相关系数为0.9991;其他参数基本不受影响。结论:黄疸、乳糜均对血细胞分析的部分参数产生影响。 相似文献
3.
The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD. 相似文献
4.
Jan Schmeller Michael Wessolly Elena Mairinger Sabrina Borchert Thomas Hager Thomas Mairinger Kurt Werner Schmid Jeremias Wohlschlaeger Robert F.H. Walter Fabian D. Mairinger 《Pathology, research and practice》2019,215(2):381-386
Introduction
The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.Design
FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (?80?°C, ?20?°C, 4?°C, 24?°C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.Results
The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20?°C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.Conclusion
FFPE sections not directly used for RNA extraction should be stored below -20?°C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results. 相似文献5.
6.
目的探讨术中氧化亚氮暴露对半椎体切除术患儿术后血细胞形态和数量的影响。方法回顾性分析2013年1月至2020年7月因先天性半椎体畸形接受后路半椎体切除术的患儿245例,男152例,女93例,年龄18岁,根据术中是否使用氧化亚氮分为暴露组(n=143)和对照组(n=102)。比较术后发生贫血、大红细胞症、小红细胞症、红细胞大小不等症等血细胞形态学和白细胞减少、血小板减少等血液学改变情况。采用多重线性回归分析氧化亚氮吸入与平均红细胞体积的最大变化程度(dMCV)的相关性。结果暴露组与对照组均有较高的术后贫血发生率(55.9%vs 57.8%)。两组均未观察到大红细胞症。暴露组有7例(4.9%),对照组有3例(2.9%)红细胞大小不等症。暴露组和对照组各有50例(35.0%)和46例(45.1%)小红细胞症。暴露组和对照组各有2例(1.4%)和4例(3.9%)白细胞减少。对照组有3例发生血小板减少。两组血细胞异常发生率差异均无统计学意义。年龄与dMCV呈负相关。结论在接受后路半椎体切除术患儿中,使用氧化亚氮进行麻醉对围术期血液学指标无显著影响。 相似文献
7.
To determine whether hepatic microsomal enzyme induction occurs in rats following administration of phenobarbital at doses similar to those used in humans (0.5 to 7.5 mg/kg), UDP-glucuronyl transferase (UDPGT) and cytochrome P-450 activities were measured in liver homogenate and microsomal preparations from control rats and rats treated for 6 days with phenobarbital at 1 and 3 mg per kg per day. While no significant increases in liver weight and protein content of homogenate and microsomal preparations were observed with either dose of the drug, both UDPGT and P-450 activities were enhanced significantly following administration of phenobarbital at 3 mg per kg per day. The activity of P-450 was increased by approximately 30% and that of UDPGT by 15-24 and 45-66%, respectively, employing bilirubin and p-nitrophenol as the acceptor substrate. The extent of induction of bilirubin or p-nitrophenol UDPGT was similar when measured with "native" enzyme or with enzyme activated by UDP-N-acetyl glucosamine, digitonin or deoxycholate. These data suggest that the discordant effects of phenobarbital on UDPGT and cytochrome P-450 previously reported in humans and rats may not be attributable solely to differences in the drug doses employed. 相似文献
8.
E R Eichner 《The American journal of medicine》1983,75(6):1008-1023
The "exercise hypothesis" states that exercise protects against coronary heart disease. Reviewed herein is the epidemiologic evidence for and against the "exercise hypothesis." The weight of evidence supports the view that exercisers have a lower risk of coronary disease, but that vigorous exercise cannot always prevent progression of coronary atherosclerosis and does increase the risk of sudden death in persons with advanced coronary atherosclerosis. It is concluded that the "exercise hypothesis" is plausible, even likely, but still unproved. 相似文献
9.
D M Hays R B Raney W Lawrence M Tefft E H Soule W M Crist M Foulkes H M Maurer 《Journal of pediatric surgery》1982,17(6):812-820
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory. 相似文献
10.
《Gait & posture》2017
Knee osteoarthritis (KOA) is the most common osteoarthritis in lower limbs, and gait measurement is important to evaluate walking function of KOA patients before and after treatment. The third generation Intelligent Device for Energy Expenditure and Activity (IDEEA3) is a portable gait analysis system to evaluate gaits. This study is to evaluate the accuracy and reliability of IDEEA3 for gait measurement of KOA patients. Meanwhile, gait differences between KOA patients and healthy subjects are examined. Twelve healthy volunteers were recruited for measurement comparison of gait cycle (GC), cadence, step length, velocity and step counts between a motion analysis system and a high-speed camera (GoPro Hero3). Twenty-three KOA patients were recruited for measurement comparison of former five parameters between GoPro Hero3 and IDEEA3. Paired t-test, Concordance Correlation Coefficient (CCC) and Intraclass Correlation Coefficient (ICC) were used for data analysis. All p-values of paired t-tests for GC, cadence, step length and velocity were greater than 0.05 while all CCC and ICC results were above 0.95. The measurements of GC, cadence, step length, velocity and step counts by motion analysis system are highly consistent with the measurements by GoPro Hero3. The measurements of former parameters by GoPro Hero3 are not statistically different from the measurements by IDEEA3. IDEEA3 can be effectively used for the measurement of GC, cadence, step length, velocity and step counts in KOA patients. The KOA patients walk with longer GC, lower cadence, shorter step length and slower speed compared with healthy subjects in natural speed with flat shoes. 相似文献