简介:摘要目的分析我国南北两城市深圳和太原市大气细颗粒物(PM2.5)主要成分及其污染来源。方法采集2017至2018年深圳和太原市空气中PM2.5样品,用电感耦合等离子体质谱法测定铅(Pb)、铝(Al)、砷(As)等10种金属元素浓度,用离子色谱法测定氟化物(F-)、氯化物(Cl-)、硫酸盐(SO42-)等10种水溶性离子浓度,用高效液相色谱法测定萘、苊烯、苊等16种多环芳烃(PAHs)浓度,用碳质分析仪测定有机碳(OC)与元素碳(EC)含量;采用因子分析法分析PM2.5的污染来源。结果太原市PM2.5样品中Pb、锰(Mn)、As、镍(Ni)、F-、OC、EC浓度明显高于深圳市,钠盐(Na+)、Cl-、磷酸盐(PO43-)浓度低于深圳市(P<0.05);除萘外,太原市PM2.5样品中其余PAHs浓度均高于深圳市(P<0.05)。深圳市PM2.5样品中金属元素与水溶性离子污染来源由工业排放/机动车尾气因子(42.64%)、建筑/土壤因子(34.22%)和海洋因子(17.93%)构成,PAHs主要来源于燃油与机动车尾气因子(38.58%)、燃煤因子(30.78%)、生物质燃烧因子(24.38%)。太原市PM2.5样品中金属元素与水溶性离子来自建筑因子(30.26%)、燃油燃煤因子(24.58%)、二次粒子/土壤因子(22.03%)及工业因子(18.89%),PAHs主要来自燃油与机动车尾气因子(54.71%)、燃煤因子(43.54%)。结论深圳和太原市PM2.5成分存在较大差异,需要进一步加强企业的环境健康管理,根据各地污染来源有针对性进行治理。
简介:AbstractBackground:Aberrant activation of the complement system plays an important role in the pathogenesis and development of immunoglobulin A nephropathy (IgAN). The relationship between serum complement and the clinical-histopathological features and outcomes of IgAN is controversial. This retrospective study aimed to examine the relationship between the complement 3/4 (C3/C4) ratio and the clinicopathologic changes and prognosis of patients with IgAN.Methods:A total of 397 patients with primary IgAN from January 2007 to December 2012 at the Chinese People’s Liberation Army General Hospital were included in this study. The correlation test and Chi-square test or one-way analysis of variance test were performed to evaluate the relationship between the C3/C4 ratio and other clinical-pathological factors. Propensity score matching and a multivariate Cox regression model were used to calculate the risk factors of renal outcome.Results:The median follow-up period was 75 months. During the follow-up period, 62 patients (15.6%) developed into the end-stage renal disease (ESRD). The C3/C4 ratio at baseline was associated with the level of serum creatinine (SCr), 24 h urinary protein excretion (24 h Upre), global glomerular sclerosis, and tubulointerstitial lesion. The level of SCr and 24 h Upre and the degree of chronic kidney injury were statistically different among groups defined by different C3/C4 ratio levels. The survival rates of patients among groups with different C3/C4 ratio levels were different. After propensity score matching, eighty-eight pairs of patients were successfully matched, and the C3/C4 ratio was an influencing factor for the patients’ outcome (hazard ratio 0.587, 95% confidence interval 0.329-0.880). Patients with a C3/C4 ratio <3.6 had a poorer outcome compared with the others (P = 0.002).Conclusions:IgAN patients with decreased C3/C4 ratio displayed significantly more severe clinical symptoms and chronic renal injury than patients with higher ratios. A low C3/C4 ratio could be a risk factor for patients developing to ESRD.
简介:摘要: 火电厂在实际运行的过程中,最容易发生故障的类型就是电气设备故障,基于此,本篇文章主要对电气设备故障以及实际的故障处理方法进行深入的探究和分析。
简介:摘要目的探索脂多糖(LPS)对大鼠心脏微血管内皮细胞(rCMECs)转录组的调节作用。方法对照组(正常培养rCMECs),LPS组(100 ng/mL LPS处理6 h的rCMECs),每组进行3个生物学重复转录组测序。得到差异基因后,使用实时定量PCR对部分差异基因mRNA的表达进行验证。分别对上调和下调基因进行GO和KEGG富集,并对差异基因进行共表达网络分析。采用独立t检验进行统计学分析。结果LPS处理后,265个基因表达上调,118个基因的表达下调。前10个最显著上调基因为:Mt2a、Cyp7b1、Sod2、Icam1、Ccl2、AC128848.1、Mt1、Cebpd、Serpinb2和Tnfrsf11b。前10个最显著下调基因为:Cavin2、Ankrd1、Edn1、Prss35、Lmod1、Dhrs3、Ttc22、Sema6a、Map2k3和Sema7a。定量PCR的结果表明Mt2a、Sod、Ccl2、Cxcl1、Icam1和Vcaml基因的表达得到了上调(P均< 0.01);而Cavin2、Ankrd1、Edn1和Prss35基因表达下调(P均< 0.05)。GO和KEGG富集的结果表明,上调基因与内皮细胞对炎性免疫细胞的趋化作用和黏附作用密切相关;而下调基因则是与钙离子信号和G蛋白相关通路以及内皮通透性增加有关。此外,差异基因进行共表达网络分析发现Sod2处于核心位置,提示其可能与LPS诱导的rCMECs的各种变化密切相关。结论LPS调控了rCMECs中大量与炎性免疫细胞进入心肌组织相关基因的表达。
简介:摘要目的了解分化中晶状体的转录谱,包括mRNA、长链非编码RNA(lncRNA)和环状RNA(circRNA)。方法实验研究。提取人源性分化晶状体RNA并纯化。然后使用Illumina HiSeq 2500对16、23、25周晶状体总RNA样本进行测序,并使用生物信息学工具进行分析,筛选出最高表达和差异表达的mRNA和lncRNA;用维恩图分析3个时期晶状体的重叠基因表达情况;分析晶状体特异性基因的表达趋势,并用实时荧光定量PCR验证。结果在16、23、25周晶状体中分别获得67 518 311、99 440 160和67 262 320条映射序列。基因重叠表达分析显示,前1 000个高表达mRNA、前300个高表达lncRNA和前100个高表达circRNA中分别有740、170、69个在16、23、25周晶状体中同时表达。晶状体特异性基因表达分析显示,晶状体蛋白(CRY)AA、CRYGA、CRYGB、CRYGC、CRYGD、CRYGEP和CRYGS基因表达随晶状体分化时间上调,缝隙连接(GJ)蛋白GJA3和GJA8基因表达随晶状体分化时间下调。结论晶状体转录组表达谱显示不同分化阶段晶状体的高表达mRNA、lncRNA和circRNA中重叠表达者占半数以上,且均高表达晶状体特异性蛋白基因,如CRY、GJ蛋白基因等。(中华眼科杂志,2020,56:356-363)
简介:摘要目的分析1个诺里病家系的致病基因变异,确定其遗传学病因。方法对先证者核心家系4名成员的DNA样本进行全外显子组检测,筛选变异位点,确定致病基因。通过Sanger测序对核心家系及7名其他家系成员进行验证。结果全外显子组检测及Sanger测序结果显示先证者及另外3例男性患者的NDP基因均存在c.361C>T(p.Arg121Trp)半合子错义变异,先证者母亲、外祖母和2个表妹均为c.361C>T杂合变异携带者,正常表型男性家系成员均未检测到该变异,符合X连锁隐性遗传病的特点。结论NDP基因c.361C>T错义变异是该诺里病家系的遗传学病因。
简介:AbstractBackground:Developing effective spinal cord repair strategies for spinal cord injury (SCI) is of great importance. Emerging evidence suggests that microRNAs (miRNAs) are closely linked to SCI recovery. This study aimed to investigate the function of miR-34c in the neuronal recovery in rats with SCI.Methods:A rat model with SCI was established. Differentially expressed miRNAs were identified by a microarray analysis. MiR-34c expression in rats was measured by reverse transcription quantitative polymerase chain reaction. Altered expression of miR-34c or C-X-C motif ligand 14 (CXCL14) was introduced in SCI rats to measure their roles in neuronal recovery. Western blot analysis was performed to determine the phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription-3 (STAT3). Neuronal apoptosis in rat spinal cord tissues was detected. The concentrations of SCI recovery-related proteins thyrotropin releasing hormone (TRH), prostacyclin (PGI2), and ganglioside (GM) were evaluated by enzyme-linked immunosorbent assay. Data were analyzed using a t-test with a one-way or two-way analysis of variance.Results:Rats with SCI presented decreased grip strength (112.03 ± 10.64 vs. 17.32 ± 1.49 g, P < 0.01), decreased miR-34c expression (7 days: 3.78 ± 0.44 vs. 0.95 ± 0.10, P < 0.05), and increased CXCL14 expression (7 days: 0.61 ± 0.06 vs. 2.91 ± 0.27, P < 0.01). MiR-34c was found to directly bind to CXCL14. Overexpression of miR-34c increased grip strength (11.23 ± 1.08 vs. 31.26 ± 2.99 g, P < 0.01) and reduced neuronal apoptosis in spinal cord tissues (53.61% ± 6.07% vs. 24.59% ± 3.32%, P < 0.01), and silencing of CXCL14 also increased the grip strength (12.76 ± 1.13 vs. 29.77 ± 2.75 g, P < 0.01) and reduced apoptosis in spinal cord tissues (55.74% ± 6.24% vs. 26.75% ± 2.84%, P < 0.01). In addition, miR-34c upregulation or CXCL14 downregulation increased the concentrations of TRH, PGI2, and GM, and reduced phosphorylation of JAK2 and STAT3 in rats with SCI (all P < 0.01).Conclusion:The study provided evidence that miR-34c could promote neuronal recovery in rats with SCI through inhibiting CXCL14 expression and inactivating the JAK2/STAT3 pathway. This study may offer new insights into SCI treatment.
简介:摘要:响应市区共建暨何伟校长共同体,本着学习提高,研究促进发展的目的,我准备了这一堂课《感受磁场力》,准备过程前后,不同老师给与了指导和中肯评价,感受了不同老师对内容理解的深刻、设计的巧妙、思维的缜密和角度的新颖。本节课设计之初,考虑到教学进度,在人教版选修 3-1磁场一章《安培力》讲完后,想设计一堂感受课,独立于教材之外,又让学生加深课本内容的感悟,这样的课学生们可能没有感受过,如果增加一些对知识内容的体验,未尝不是一件好事,像高考 2017年新课标二卷理综 21题,就有这部分内容和细节的考察,本着增加学生形象感受,对学生理解具体问题和分析会有所帮助,于是我就着手安排了一堂这样课的设计和尝试。