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71.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged in Chinese people in December 2019 and has currently spread worldwide causing the COVID-19 pandemic with more than 150,000 deaths. In order for a SARS-CoV like virus circulating in wild life for a very long time to infect the index case-patient, a number of conditions must be met, foremost among which is the encounter with humans and the presence in homo sapiens of a cellular receptor allowing the virus to bind. Recently it was shown that the SARS-CoV-2 spike protein, binds to the human angiotensin I converting enzyme 2 (ACE2). This molecule is a peptidase expressed at the surface of lung epithelial cells and other tissues, that regulates the renin-angiotensin-aldosterone system. Humans are not equal with respect to the expression levels of the cellular ACE2. Moreover, ACE2 polymorphisms were recently described in human populations. Here we review the most recent evidence that ACE2 expression and/or polymorphism could influence both the susceptibility of people to SARS-CoV-2 infection and the outcome of the COVID-19 disease. Further exploration of the relationship between the virus, the peptidase function of ACE2 and the levels of angiotensin II in SARS-CoV-2 infected patients should help to better understand the pathophysiology of the disease and the multi-organ failures observed in severe COVID-19 cases, particularly heart failure.  相似文献   
72.
The identification of EGFR mutations in non‐small‐cell lung cancer is important for selecting patients, who may benefit from treatment with EGFR tyrosine kinase inhibitors. The analysis is usually performed on cytological aspirates and/or histological needle biopsies, representing a small fraction of the tumour volume. The aim of the present investigation was to evaluate the diagnostic performance of this molecular test. We retrospectively included 201 patients with primary adenocarcinoma of the lung. EGFR mutation status (exon 19 deletions and exon 21 L858R point mutation) was evaluated on both pre‐operative biopsies (131 histological and 70 cytological) and on the surgical specimens, using PCR. Samples with low tumour cell fraction were assigned to laser micro‐dissection (LMD). We found nine (4.5%) patients with EGFR mutation in the lung tumour resections, but failed to identify mutation in one of the corresponding pre‐operative, cytological specimens. Several (18.4%) analyses of the pre‐operative biopsies were inconclusive, especially in case of biopsies undergoing LMD and regarding exon 21 analysis. Discrepancy of mutation status in one patient may reflect intra‐tumoural heterogeneity or technical issues. Moreover, several inconclusive results in the diagnostic biopsies reveal that attention must be paid on the suitability of pre‐operative biopsies for EGFR mutation analysis.  相似文献   
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This is the first Japanese autopsy case of Leucine-rich repeat kinase 2 (LRRK2) G2019S mutation with atypical TDP43 proteinopathy. Our case is important that presented clinically dysphagia and pathologically TDP-43 proteinopathy. TDP43 may play an important role of clinical presentation with LRRK2 G2019S mutation carriers.  相似文献   
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76.
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.  相似文献   
77.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
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79.
宋旭辉  郭琴  林胜  刁雪  付英  王华国 《中国热带医学》2020,20(11):1120-1122
目前新型冠状病毒肺炎(COVID-19)疫情在全球蔓延,形势严峻,并对全球公共卫生事业构成巨大挑战,快速准确的诊断COVID-19对疫情的防控有重要意义。本文报道1例COVID-19患者的调查和确诊过程,以对COVID-19确诊和疫情防控提供有价值的参考。患者为赴渝务工于2020年1月23日返乡人员,在渝期间,其同工地的一同事确诊为COVID-19,之后该工地接连有另外8位同事被确诊。患者返乡后2月2日被当地疫情防控单位采取医学隔离。患者于隔离后不久出现咳嗽,阵发性,干咳为主,偶可咳出黄色痰液等COVID-19相关临床症状,遂被当地新型冠状病毒肺炎定点医疗单位收治,后经市级新型冠状病毒肺炎诊治专家组远程视频会诊转入四川大学华西医院资阳医院。患者先后经历9次核酸检测,在前8次核酸检测均为阴性的情况下,于第9次核酸检测结果为阳性,2月21日最终确诊为新型冠状病毒肺炎。  相似文献   
80.
目的:研究长柱重楼、滇重楼和南重楼的HPLC指纹图谱与其抗肝癌作用的谱效关系,为明确重楼抗肝癌作用的物质基础提供实验依据。方法:采用HPLC建立3种重楼提取物的指纹图谱,流动相乙腈(A)-水(B)梯度洗脱(0~10 min,20%A; 10~20 min,20%~25%A; 20~30 min,25%~30%A; 30~40 min,30%~35%A; 40~50 min,35%~40%A; 50~60 min,40%A; 60~75 min,40%~45%A; 75~80 min,45%~60%A),流速0. 9 m L·min~(-1),检测波长203 nm;利用噻唑蓝(MTT)比色法测定3种重楼提取物对肝癌HepG2细胞的增殖抑制作用,计算半数抑制浓度(IC_(50));运用聚类分析(HCA)和灰色关联度分析(GRA)研究3种重楼指纹图谱和抗肝癌作用的关系,找出对抗肝癌作用贡献较大的成分。结果:在3种重楼的HPLC指纹图谱中,确定其中11个色谱峰为共有峰。作用时间72 h时长柱重楼、滇重楼、南重楼的IC_(50)分别为148. 33,178. 87,208. 09 mg·L~(-1),其中长柱重楼的抗肝癌活性最强。灰色关联度结果显示,滇重楼共有峰中关联度较高的为1~10号峰,长柱重楼共有峰关联度较高的为1~7号峰,南重楼共有峰中关联度较高的为1~4,6~10,N1号峰,与IC_(50)关联度均0. 7。各重楼变量的聚类分析结果显示,可与IC_(50)聚为一类的色谱峰的关联度均 0. 7。结论:建立了3种重楼的HPLC指纹图谱,重复性良好。3种重楼中的1~4,6和7号色谱峰对抗肝癌药效贡献最大。  相似文献   
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