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991.
Non-destructive testing using a magneto-optical effect is a high-resolution non-destructive inspection technique for a metallic structure. It is able to provide high-spatial resolution images of defects. Previously, it has been difficult to fabricate flexible magneto-optical sensors because thermal treatment is necessary to crystallize the magnetic garnet. Therefore, it was not possible to apply magneto-optical imaging to complicated shapes in a test subject, such as a curved surface. In this study, we developed a new process for deposition of the magnetic garnet on the flexible substrate by applying the magnetic garnet powders that have already undergone crystallization. In this new process, as it does not require thermal treatment after deposition, flexible substrates with low heat resistance can be used. In this paper, we report our observations of the optical properties, magnetic hysteresis loop, crystallizability and density of the particles on the flexible substrate deposited by the spin-coating method. 相似文献
992.
The magnetic method is the most promising method that can be used to inspect large areas of reinforced concrete (RC) structures. Magnetization is a crucial process in this method. The paper aims to present the impact of the magnetization method on the results in the detection of reinforced bars (rebars) and the evaluation of concrete cover thickness in reinforced concrete (RC) structures. Three cases (without magnetization, same pole magnetization, and opposite pole magnetization) were considered in the experiments. Results achieved in all the methods are presented and evaluated. Two different sensing elements were used in the measurements: a magneto-optical (MO) sensor and an AMR sensor. The advantages and disadvantages of both mentioned transducers are presented and discussed in the context of a large areas inspection. The new approach involves using various magnetization methods to improve measurement results for complex structures. 相似文献
993.
全国细菌耐药监测网 《中国感染控制杂志》2021,20(2):168-174
目的 了解全国粪便标本分离病原菌的菌群分布及耐药情况.方法 从2014-2019年全国细菌耐药监测网报告中提取粪便标本的相关数据(去除肠道正常定植菌群),分析肠道致病菌及其耐药率的变迁.结果 共分离菌株61 809株,居前3位的是沙门菌属(82.12%)、志贺菌属(8.08%)、弧菌属(4.03%),沙门菌属在每年粪便... 相似文献
994.
出生缺陷是我国乃至全球所面临的严峻挑战,指婴儿出生前发生的身体结构、功能或代谢异常,与环境、遗传因素密切相关,其中遗传因素又包括染色体异常与基因突变[1]。罕见遗传病作为出生缺陷的重要组成部分,80%~85%具有遗传基础,且绝大多数由基因突变导致[2]。
浏览更多请关注本刊微信公众号及当期杂志。 相似文献
995.
《Taiwanese journal of obstetrics & gynecology》2020,59(1):16-20
Non-invasive prenatal testing (NIPT) is performed worldwide to detect common chromosomal aneuploidies. The analysis of cell-free DNA (cfDNA) in maternal blood for NIPT is highly accurate for the detection of the main fetal trisomies: 21,18, and 13. However, false-positive, false-negative, and non-reportable results can occur, and these can have biological causes. Understanding the causes of unexpected NIPT results is essential to enable clinicians and genetic counselors to counsel patients comprehensively and appropriately, both prior to testing as well as after receiving the test results. The classification of non-reportable results from cfDNA analysis is important in order to provide women with precise information. In addition to technical issues, there are biological reasons for discordant results, which can be either fetal or maternal in origin. Contributing fetal factors include insufficient or absent fetal fraction, fetoplacental mosaicism, and the presence of a vanishing twin. In some pregnant women that test positive for NIPT, multiple chromosome aneuploidy has been reported as a result of suspected malignancy, and cancer has been found. False-positive and false-negative results may be the result of placental biology and not a failure in the actual test platform. Explaining the placental origin of cfDNA provides the patient with a clear view of the abilities and limitations of cfDNA-based prenatal screening. 相似文献
996.
本文报道了1例KLHL40基因复合杂合突变导致线状体肌病的病例。患儿女,生后即起病,以"气促、肌力、肌张力低"为主要表现,常规治疗后症状加重,体格检查示四肢肌力低、肌张力低,原始反射均未引出;血清肌酸激酶升高。患儿未行肌肉活检。采用全外显子组二代测序证实患儿存在KLHL40基因复合杂合突变,包括c.932G>T(p.R311L)和c.1487T>A(p.M496K),并且分别来源于父母,其中c.932G>T(p.R311L)为已发现的突变位点,c.1487T>A(p.M496K)为新发现的突变位点。线状体肌病是一种罕见的先天性肌肉疾病,肌纤维中发现线状体是特征性肌肉病理改变。病理及基因诊断是诊断线状体肌病的金标准。 相似文献
997.
《Taiwanese journal of obstetrics & gynecology》2020,59(4):489-495
Preimplantation genetic testing for aneuploidies (PGT-A) and PGT for monogenic disorders (PGT-M) have currently been used widely, aiming to improve IVF outcomes. Although with many years of unsatisfactory results, PGT-A has been revived because new technologies have been adopted, such as platforms to examine all 24 types of chromosomes in blastocysts. This report compiles current knowledge regarding the available PGT platforms, including quantitative PCR, array CGH, and next-generation sequencing. The diagnostic capabilities of are compared and respective advantages/disadvantages outlined. We also address the limitations of current technologies, such as assignment of embryos with balanced translocation. We also discuss the emerging novel PGT technologies that likely will change our future practice, such as non-invasive PGT examining spent culture medium. Current literature suggest that most platforms can effectively reach concordant results regarding whole-chromosome ploidy status of all 24 types of chromosomes. However, different platforms have different resolutions and experimental complexities; leading to different turnaround time, throughput and differential capabilities of detecting mosaicism, segmental mutations, unbalanced translocations, concurrent PGT-A and PGT-M etc. Based on these information, IVF staff can more appropriately interpret PGT data and counsel patients, and select suitable platforms to meet personalized needs. The present report also concisely discusses some crucial clinical outcomes by PGT, which can clarify the role of applying PGT in daily IVF programs. Finally the up-to-date information about the novel use of current technologies and the newly emerging technologies will also help identify the focus areas for the design of new platforms for PGT in the future. 相似文献
998.
目的了解儿童金黄色葡萄球菌(金葡菌)肺炎致病株分子特征及耐药性,供临床诊治参考。方法收集2016年1月至2017年3月首都医科大学附属北京儿童医院确诊为金葡菌肺炎患者分离株,采用头孢西丁纸片法和mecA检测鉴定耐甲氧西林金葡菌(MRSA)或甲氧西林敏感金葡菌(MSSA);对所有菌株进行多位点序列分型(MLST)和葡萄球菌蛋白A(spa)分型,并对MRSA菌株进行葡萄球菌盒氏染色体(SCCmec)分型;采用PCR方法检测21种超抗原(SAgs)基因、杀白细胞素(PVL)基因、黏附基因fnbB、cna;采用琼脂稀释法、E-test检测14种抗生素体外药物敏感性。结果共收集42株金葡菌,其中MRSA、MSSA各21株。MRSA的优势克隆为ST59-SCCmecⅣa-t437(71.4%);MSSA的分型较为分散,以ST25-t078(14.2%)最多见。42株金葡菌中有36株(85.7%)至少携带1种超抗原基因,最常见的超抗原基因型为sek-seq(21.4%);MRSA pvl基因携带率(52.3%)明显高于MSSA(14.2%),而MSSA fnbB及cna基因携带率(42.8%和47.6%)明显高于MRSA(均为9.5%),差异均有统计学意义(均P<0.05)。本组金葡菌多重耐药率达90.4%(38/42株)。结论MRSA在儿童金葡菌肺炎致病株中检出率高,其主要克隆型为ST59-SCCmecⅣa-t437。儿童肺炎金葡菌分离株的超抗原基因携带率和多重耐药率较高,MRSA菌株常携带pvl基因,而MSSA菌株携带fnbB、cna更常见。 相似文献
999.
1000.
Mohammed Abu El‐Hamd Manar Ibrahim Abd Elhameed Mona Fattouh Mohamed Shalaby Ramadan Saleh 《Dermatologic therapy》2020,33(3)
Onychomycosis is the most common nail disorder. To examine in vitro antifungal susceptibility of fungi among onychomycosis patients. The study included 68 patients with onychomycosis. Nail specimens were cultured on Sabouraud dextrose agar and Dermasel agar base‐media. Isolated fungi were subjected to antifungal susceptibility tests against terbinafine, itraconazole, fluconazole, and griseofulvin. Candida species (Candida spp.) were detected in 32.4% of the cases of candidal onychomycosis (n = 37), 23.5% of the cases of distal and lateral subungual onychomycosis (n = 17), and 21.4% of the cases of total dystrophic onychomycosis (n = 14). Candida spp. were sensitive to fluconazole in 73.5%, itraconazole in 58.8%, and terbinafine in 5.9% of the cases. Aspergillus spp. were sensitive to itraconazole in all cases, and terbinafine in 87.5% of cases. Penicillium spp. were sensitive to itraconazole and terbinafine in 88.9% and 77.8% of cases, respectively. Trichophyton spp. were sensitive to terbinafine and resistant to itraconazole. Microsporum spp. were sensitive to itraconazole and resistance to terbinafine. All isolated fungi were resistant to griseofulvin. An increasing proportion of Candida spp. was observed among patients with different clinical varieties of onychomycosis. Candida spp. were highly sensitive to fluconazole and a lesser extent to itraconazole. 相似文献