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本文应用雄性小鼠生殖细胞非程序DNA合成(UDS)检测方法研究了“美容牌”染发剂对雄性生殖细胞DNA的损伤作用。发现该染发剂诱发的UDS与药物剂量呈线性正相关。提示此类染发剂对雄性生殖细胞DNA有损伤作用。其遗传毒理效应应引起注意。 相似文献
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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6.
This female patient was born in 1935 and died in 1976 with a malignant bone tumor involving the proximal humerus following multiple local recurrences, axillary lymph node metastases, and pulmonary metastases. Histologically, over the course of time, there was an increase in features of an atypical Ewing's sarcoma, at the expense of findings of a typical, extra-cranial so-called adamantinoma. In contrast to another report, our case showed neither epithelial nor endothelial features on fine structural examination, but rather primitive mesenchymal cells, as is described for Ewing's sarcomas. 相似文献
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Surrogate-reared infant squirrel monkeys were exposed to various conditions of separation from their surrogate. Infants showed significant increases in plasma levels of cortisol when they were placed in an unfamiliar environment during the separation period. Changes in behavior, but not cortisol, were observed under conditions in which the surrogate was removed and the infant left in the home cage. These results differ from those previously obtained with mother-reared infants. It is concluded that surrogate-reared infant squirrel monkeys do not show the same separation response or attachment to their rearing figure as do mother-reared infants. 相似文献
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目的比较传统外侧“L”形切口钢板内固定与跗骨窦小切口微型钢板内固定治疗跟骨骨折患者的效果。方法选取福建医科大学附属三明第一医院2019年1—12月收治的59例跟骨骨折患者,随机分为试验组(31例)和对照组(28例)。对照组采取外侧“L”形切口钢板内固定治疗,试验组采取跗骨窦小切口微型钢板内固定治疗,比较两组的治疗效果。结果试验组手术时间、住院时间均短于对照组,术中出血量少于对照组,差异有统计学意义(P<0.05);两组骨折愈合时间比较,差异无统计学意义(P>0.05)。术后,两组跟骨结节关节角、Gissane角均大于术前,差异有统计学意义(P<0.05);但组间跟骨结节关节角、Gissane角比较,差异无统计学意义(P>0.05)。试验组并发症发生率低于对照组,Maryfand评分、足部功能恢复优良率均高于对照组,差异有统计学意义(P<0.05)。结论跗骨窦小切口微型钢板内固定治疗跟骨骨折患者的效果优于传统外侧“L”形切口钢板内固定,可有效促进患者足部功能恢复,且安全性较高。 相似文献
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Based on lateral hypothalamic self-stimulation behavior of the rat in a Skinner box, a "conflict" situation was established by combining foot shock punishment with brain stimulation. Diazepam (10-20 mg/kg, PO) caused a marked increase in the lever pressing response in the punished period without affecting the unpunished response. Bromazepam (10--20 mg/kg PO) also caused an increase in the lever pressing response in the punished period and a decrease of the punished response. These results indicate that a "conflict" situation based on self-stimulation behavior is useful for the evaluation of antianxiety action. 相似文献
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唐正琪 《中国眼耳鼻喉科杂志》2019,(1):35-38
目的探讨改良Blair切口和改良倒"V"形防皱切口下腮腺浅叶肿瘤切除术对患者围术期临床指标、美观性及术后并发症的影响。方法选取我院2013年1月~2017年5月收治行腮腺浅叶肿瘤切除术的患者共142例,以随机数字表法分为对照组(71例)和改良组(71例),分别在改良Blair切口(对照组)和改良倒"V"形防皱切口(改良组)下完成手术。比较2组患者手术时间、术中出血量、术后12个月美学VAS及术后并发症发生率。结果 2组患者手术时间和术中出血量比较差异无统计学意义(P> 0. 05);改良组患者术后12个月美学VAS显著高于对照组(P <0. 05); 2组患者术后暂时性面瘫、味觉性出汗综合征、耳周麻木及涎瘘复发率比较差异无统计学意义(P> 0. 05)。结论改良Blair切口和改良倒"V"形防皱切口下腮腺浅叶肿瘤切除术具有相近的操作难度、医源性创伤程度及安全性,但改良倒"V"形防皱切口下操作更有助于改善术后美观性,提高治疗依从性。 相似文献