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排序方式: 共有485条查询结果,搜索用时 46 毫秒
1.
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2.
D. O. McDaniel B. O. Barger R. T. Acton W. J. Koopman G. S. Alarcón 《Tissue antigens》1989,34(5):299-308
Analysis of HLA DRB1 and DQB1 Bam HI RFLPs revealed four DRB1 (4.8, 5.2, 6.0 and 7.0 kb) fragments and a 3.2 kb DQB1 fragment to be significantly increased in Caucasians with seropositive RA compared to healthy individuals. The 4.8, 5.2 and 7.0 kb DRB1 fragments were found in 86.5% of RA patients and in 56% of the controls (p = 10(-3), relative risk (RR) = 5.0), while the 6.0 kb fragment was found in 79% of RA patients compared to 32% of controls (p = 2 x 10(-5), RR = 8.0). The 3.2 kb DQB1 fragment was observed in 63.5% of RA patients versus 38.0% of controls (p = 10(-2), RR = 2.8). Analysis of these fragments relative to HLA phenotypes revealed that the 4.8, 5.2 and 7.0 kb DRB1 fragments were strongly correlated with DR4, -7, -9 and -w53 serotypes, the 6.0 kb RFLP with DR4 and the 3.2 kb DQB1 fragment with DR1 and DQw1. Using probes specific for the 5' or 3' regions of the DRB1 gene, the 5.2 and 6.0 kb DRB RFLPs were mapped to the 5' end and the 4.8 and 7.0 kb RFLPs to the 3' end of the DRB1 gene. A probe generated from the second exon of the DRB4 (DRw53) gene recognized only the 5.2 and the 6.0 kb RFLPs corroborating the 5' location of these RFLPs. Family studies further confirmed that these RFLP's segregated with HLA phenotypes. 相似文献
3.
4.
目的 :探讨自攻自断螺纹钉在大面积缺损牙保存性修复中的应用。方法 :采用自攻自断螺纹钉 ,选择凡因龋坏或者外伤使牙体组织损失残缺过大、牙髓未露、活力正常的牙进行修复。结果 :本组 5 0例经自攻自断螺纹钉进行固位修复 ,5年后随访 42例 ,除 2例因上颌磨牙牙尖折断而不能修复拔除外 ,其它 40例均达到评判标准 ,总成功率达 95 %。结论 :自攻自断螺纹钉主要用于对严重缺损而牙髓健康的牙进行保存性修复 ,还可对要做壳冠修复的牙进行牙壁加固。该方法因材料来源方便 ,临床效果显著 ,值得推广。 相似文献
5.
Topi Laaksonen Jani Puhakka Antti Stenroos Jussi Kosola Matti Ahonen Yrjn Nietosvaara 《Journal of children's orthopaedics》2021,15(1):63
PurposeCompletely displaced distal radius fractures in children have been traditionally reduced and immobilized with a cast or pin fixed. Cast immobilization leaving the fracture displaced in the bayonet position has been recently suggested as a non-invasive and effective treatment alternative. This is a pilot comparative study between reduction and no reduction.MethodsWe assessed subjective, functional and radiographic outcome after a minimum 2.5-year follow-up in 12 children under ten years of age who had sustained a completely displaced metaphyseal radius fracture, which had been immobilized leaving the fracture in an overriding position (shortening 3 mm to 9 mm). A total of 12 age-matched patients, whose similar fractures were reduced and pin fixed, were chosen for controls. ResultsAt follow-up none of the 24 patients had visible forearm deformity and the maximal angulation in radiographs was 5° Forearm and wrist movement was restored (< 10° of discrepancy) in all 24 patients. Grip strength ratio was normal in all but three surgically treated patients. All patients had returned to their previous activities. One operatively treated boy who was re-operated on reported of pain (visual analogue scale 2).ConclusionThe results of this study do not demonstrate the superiority of reduction and pin fixation over cast immobilization in the bayonet position of closed overriding distal metaphyseal radius fractures in children under ten years with normal neurovascular findings.Level of evidenceIII 相似文献
6.
Balint Nagy Erno Toth-Pal Csaba Papp Zoltan Ban Zoltan Papp 《Fetal and pediatric pathology》1998,18(3):213-219
Cystic fibrosis (CF) is the most common autosomal recessive disorder in Caucasians. The most frequent mutation associated with cystic fibrosis has been identified as the 3 bp deletion Delta F 508. While existing polymerase chain reactions (PCR) (allele specific amplification) used to screen for CF are both sensitive and specific, we tested the prenatal application of fluorescent polymerase chain reaction and subsequent DNA fragment analysis that appears to be fast and sensitive. DNA samples (n=146) isolated from amniotic fluid (n=108), chorion villus biopsies (n=6), and human peripheral blood (n=32) were analyzed for the presence of Delta F 508 using the fluorescent method. Of these, 10 carriers of Delta F 508 mutation were detected. We achieved the same results with conventional PCR and fluorescent PCR. 相似文献
7.
电喷雾离子化多级质谱对几种氨基糖苷类抗生素特征碎片的分析 总被引:2,自引:0,他引:2
应用电喷雾离子化多级质谱法分析几种含2-脱氧链霉胺的氨基糖苷类抗生索的碎片离子,并对它们的裂解规律进行分析归纳。除其它特征碎片离子峰外,所有测试样品的质谱图中都存在质荷比为163.1的归属于2-脱氧链霉胺的碎片离子峰。这些裂解规律可应用于微生物新药筛选中早期快速鉴别含2-脱氧链霉胺的氩基糖苷类抗生索,对氨基糖苷类抗生索的生产、质量监控以及在环境和食品中的微量检测也有指导意义。 相似文献
8.
《Anaesthesia and Intensive Care Medicine》2021,22(12):769-773
Understanding the complex process of production, storage and delivery of medical gases is vitally important to ensure safe and efficient practice by anaesthetists. This article discusses the medical gases commonly used in anaesthesia and intensive care and details the journey of the commonly used medical gases from production to patient delivery. It includes core knowledge for the FRCA. 相似文献
9.
《Acta orthopaedica》2013,84(1-6):249-255
Out of 87 displaced supracondylar fractures of the humerus in children, 17 were treated by open reduction and internal fixation, in eight cases because of vascular complications (with or without neurological complications) and in nine cases after unsatisfactory closed reduction. in the eight cases with vascular impairment, evacuation of the haematoma, reduction of the fracture and division of the fascia of the forearm caused a return of the radial pulse. Median nerve paralysis, in the four cases with neurological complications as well, recovered within 7 months. Fractures fixed with one pin only redislocated and needed an additional reduction-this procedure was associated with impairment of the range of motion. in spite of the selection of the most severe cases for surgery, the end result was excellent in all cases expect one and considerably better than previous results of closed reduction. Rotational deformity, however, did not decrease with age and growth. 相似文献
10.
《The Journal of foot and ankle surgery》2014,53(4):405-410
Kirschner wire (K-wire) fixation across the metatarsophalangeal joint (MTPJ) is commonly used in hammertoe repair surgery. The purpose of the present study was twofold: (1) to determine where the K-wire penetrates the metatarsal articular surface to achieve a rectus digit; and (2) to quantify the percentage of cartilage disruption to better understand the consequences of K-wire transfixation of the MTPJ. Arthrodesis was conducted on the second, third, and fourth proximal interphalangeal joints of 10 below-the-knee cadaver specimens, using a 1.6-mm K-wire. Digital alignment was confirmed with simulated weightbearing intraoperatively and radiographically. The K-wire was removed, and the MTPJ was dissected until the metatarsal head was fully exposed. The penetration point was plotted on a quadrant system with deviation noted from the epicenter. Center was defined as the point equidistant from the medial-to-lateral and superior-to-inferior edges on the distal surface of the metatarsal head, excluding the plantar condyles. Statistically significantly deviations were found in the K-wire placement from the center (35.9% ± 17.5%, p < .001), medial-to-lateral width (22.2% ± 19.2%, p < .001), and dorsal-to-plantar height (15.8% ± 25.0%, p = .002). Relative to the center, the K-wire was superior in 22 (79%), inferior in 6 (21%), medial in 22 (79%), and lateral in 6 (21%) of the cadaveric MTPJs. The mean percentage of disruption of the articular cartilage was 1.8% ± .4% and was similar for the second, third, and fourth MTPJs (p = .13) and for the left and right feet (p = .75). This information could be used to guide surgeons when they transfixate the MTPJ during hammertoe correction and might contribute to preservation of the articular cartilage. 相似文献