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931.
Two three-dimensional (3D) coordination polymers, namely MnII6(CH3COO)2(HCOO)2(IN)8(C4H8O)2(H2O) and MnIII6MnII123-O)6(CH3COO)12(IN)18(H2O)7.5 (abbreviated as MnII6 and MnII12MnIII6 respectively; HIN = isonicotinic acid), were synthesized by the reaction of Mn(CH3COO)2·4H2O and isonicotinic acid under solvothermal conditions. Magnetic studies revealed that antiferromagnetic interactions may be present in compounds MnII6 and MnII12MnIII6. Moreover, the values of −ΔSm (26.27 (MnII6) and 37.69 (MnII12MnIII6) J kg−1 K−1 at ΔH = 7 T) are relatively larger than those of the reported Mn-based coordination polymers. This work provides a great scope in the magnetocaloric effect (MCE) of pure 3d-type systems.

Two 3D coordination polymers (MnII6 and MnII12MnIII6) were synthesized. Magnetic studies revealed that they are potential magnetic materials.  相似文献   
932.
Flubendiamide has received considerable attention in the agriculture field due to its novel mode of action and excellent insecticidal activity. However, the high cost and toxicity to aquatic invertebrates associated with flubendiamide limit its agronomic utility. On the basis of the structure of the lead compound, flubendiamide, we designed and synthesized a series of novel analogues of flubendiamide bearing a alkoxyhexafluoroisopropyl moiety using 2-methyl-4-(2-alkoxyhexafluoroisopropyl) anilines as the key intermediates. Their insecticidal activities against the oriental armyworm (Mythimna separata Walker) were evaluated. The results indicated that most of the target compounds exhibited high insecticidal activities. Specifically, compound 8h showed the best insecticidal activity against the armyworm and its insecticidal activity reached 70% at 0.156 mg L−1. The LC50 value of compound 8h (0.0512 mg L−1) is nearly the same as the corresponding commercial product flubendiamide (0.0412 mg L−1). Furthermore, the acute toxicity test showed that the 48 h LC50 values of compound 8h and flubendiamide against Daphnia magna Straus were 0.0066 and 0.0021 mg L−1, respectively. The toxicity of compound 8h is obviously lower than flubendiamide.

A series of novel analogues of flubendiamide bearing alkoxyhexafluoroisopropyl moiety was synthesized. Their insecticidal activities against various insects were evaluated.  相似文献   
933.
Effective edge oxidation of graphene with high structural integrity is highly desirable yet technically challenging for most practical applications. In this work, we have developed a green and facile strategy to obtain edge-oxidized graphene with good dispersion stability and high electrical conductivity by exploiting high edge reactivity of highly conductive multi-layer graphene and oxidizing radicals (SO4˙) generated from sodium persulfate (Na2S2O8) with ferrous ion (Fe2+) activation. Owing to high structural integrity of pristine graphene and effective edge oxidation, the obtained edge-oxidized graphene exhibited excellent dispersion stability and satisfactory electrical conductivity (i.e. ≥240 S cm−1). Moreover, the oxidation degree of pristine graphene can be well controlled by adjusting treatment time. The obtained edge-oxidized graphene is expected to find a variety of applications in many fields of anti-static films, energy storage materials, flexible sensors and high-performance nanocomposites.

A green and facile strategy is represented to obtain edge-oxidized graphene by exploiting sulfate radicals generated from Na2S2O8 with Fe2+ activation.  相似文献   
934.
目的探讨全程管理模式在健康体检骨质疏松高危人群随访中的应用效果。方法选取2020年1月至2020年6月本院所接收骨质疏松高危人群健康体检者96例进行研究,以抽签法将受检者分为对照组、观察组,48例为一组,对照组接受常规体检护理,观察组于对照组护理方案上加施全程管理模式,并于2020年7月至2020年12月对两组进行追踪随访,比较其自护能力、骨密度、骨质疏松发生率。结果干预前两组自我护理能力测定表(ESCA)评分无明显差异(P>0.05),干预后6个月观察组自我概念、自我责任感、自护技能及健康知识水平评分均较对照组高(P<0.05);干预前两组跟骨骨密度无明显差异(P>0.05),干预后6个月观察组跟骨骨密度均较对照组高(P<0.05);随访6个月观察组骨质疏松发生率为10.42%,较对照组29.17%低(P<0.05)。结论全程管理模式用于骨质疏松高危人群健康体检中,不仅可提高受检者自护能力及骨密度,还能降低骨质疏松发生率。  相似文献   
935.
目的探讨MYNN基因的rs10936599位点多态性与急性心力衰竭(AHF)患者预后的关系。 方法选取2012年3月至2016年3月于南京医科大学第一附属医院心血管内科住院的AHF患者328例,采用TaqMan探针法对MYNN基因的SNP位点rs10936599(T/C)进行基因多态性检测,记录并比较不同基因型患者(TT基因型、CT基因型、CC基因型)住院期间的人口学特征、临床资料、病因和伴随疾病、住院期间治疗用药等基线资料,并对所有患者进行12个月的前瞻性随访,随访终点为全因死亡。分析rs10936599位点多态性对AHF预后的影响。 结果(1)rs10936599基因型频率分布:TT基因型100例(占30.5%),CT基因型162例(占49.4%),CC基因型66例(占20.1%);rs10936599位点的基因型和等位基因频率在死亡患者和存活患者间比较,差异有统计学意义(χ2=9.749,P=0.0076;χ2=9.641,P=0.0019)。(2)心率、血清钾水平及住院期间地高辛和醛固酮拮抗剂使用情况在不同基因型患者间比较,差异有统计学意义(H=7.714,P=0.021;F=3.254,P=0.040);其他基线资料在不同基因型患者间比较,差异无统计学意义(P>0.05)。(3)Kaplan-Meier曲线分析显示携带等位基因C(CC/CT)的AHF患者12个月生存率较TT基因型患者明显下降,差异有统计学意义(TT vs CT,P=0.026;TT vs CC,P=0.002)。(4)进一步Cox回归分析结果显示杂合子CT基因型和纯合子CC基因型是影响AHF患者预后的独立危险因素(HR=2.10,95%CI:1.07~4.12;HR=2.96,95%CI:1.42~6.19)。 结论MYNN基因rs10936599位点多态性与AHF患者预后有关,CC和CT基因型是预测AHF患者12个月不良预后的独立危险因素。  相似文献   
936.
BACKGROUND MUC16, encoding cancer antigen 125, is a frequently mutated gene in gastric cancer. In addition, MUC16 mutations seem to result in a better prognosis in gastric cancer. However, the mechanisms that lead to a better prognosis by MUC16 mutations have not yet been clarified.AIMTo delve deeper into the underlying mechanisms that explain why MUC16 mutations signal a better prognosis in gastric cancer.METHODSWe used multi-omics data, including mRNA, simple nucleotide variation, copy number variation and methylation data from The Cancer Genome Atlas, to explore the relationship between MUC16 mutations and prognosis. Cox regression and random survival forest algorithms were applied to search for hub genes. Gene set enrichment analysis was used to elucidate the molecular mechanisms. Single-sample gene set enrichment analysis and “EpiDISH” were used to assess immune cells infiltration, and “ESTIMATE” for analysis of the tumor microenvironment.RESULTSOur study found that compared to the wild-type group, the mutation group had a better prognosis. Additional analysis indicated that the MUC16 mutations appear to activate the DNA repair and p53 pathways to act as an anti-tumor agent. We also identified a key gene, NPY1R (neuropeptide Y receptor Y1), which was significantly more highly expressed in the MUC16 mutations group than in the MUC16 wild-type group. The high expression of NPY1R predicted a poorer prognosis, which was also confirmed in a separate Gene Expression Omnibus cohort. Further susceptibility analysis revealed that NPY1R might be a potential drug target for gastric cancer. Furthermore, in the analysis of the tumor microenvironment, we found that immune cells in the mutation group exhibited higher anti-tumor effects. In addition, the tumor mutation burden and cancer stem cells index were also higher in the mutation group than in the wild-type group.CONCLUSIONWe speculated that the MUC16 mutations might activate the p53 pathway and DNA repair pathway: alternatively, the tumor microenvironment may be involved.  相似文献   
937.
口内三维扫描技术发展迅速,精度不断提高,已被广泛应用于口腔医学领域。在单冠修复、三单位固定桥以及单枚种植体上部修复方面,口内三维扫描仪的扫描精度可满足临床要求;但在跨度过大的固定修复领域,其扫描精度仍存在不足。由于光学扫描原理的局限,目前临床难以通过口内三维扫描仪直接获取功能整塑后的软组织形态,口内三维扫描技术尚存在技术瓶颈。本文通过回顾和总结常见口内三维扫描仪对口腔软硬组织的扫描精度,分析口内三维扫描技术的临床适用性及局限性,以期为临床决策提供参考。  相似文献   
938.
目的 比较不同冲洗液和冲洗方法对根管内粪肠球菌的清除效果。方法 建立120颗人完整单根管前磨牙粪肠球菌感染根管模型,随机分组,分别采用不同冲洗液(0.9% NaCl,0.5% NaClO,3% NaClO)及冲洗方法(注射针头冲洗,超声荡洗,RinsEndo系统处理,超声荡洗协同RinsEndo系统联用)进行根管清理。无菌吸潮纸尖取样,平板菌落计数法计算CFU值,计算细菌清除率,运用SPSS 22.0软件进行统计分析,P<0.05时差异具有统计学意义。结果 使用0.9% NaCl及0.5% NaClO冲洗液时,注射针头冲洗组细菌清除率明显低于超声荡洗及RinsEndo系统处理组(P<0.001);使用3% NaClO冲洗液的各组不同的冲洗方法,细菌清除率的差异无统计学意义(P=0.556)。而无论采用哪种冲洗方法,3% NaClO溶液的细菌清除效果均优于0.5% NaClO溶液和0.9% NaCl溶液(P<0.001)。结论 不同根管冲洗液在一定程度上会影响根管冲洗方法对根管内粪肠球菌的清除效果。  相似文献   
939.
940.
Cao  Xiaofei  Wu  Junbei  Fang  Yin  Ding  Zhengnian  Qi  Tao 《Clinical oral investigations》2020,24(12):4335-4342
Objective

In this study, we aimed to assess the feasibility of fiberoptic intubation (FOI), using a new, self-designed, “tongue root holder” device, in combination with the jaw thrust maneuver.

Methods

Three hundred patients undergoing elective surgery requiring orotracheal intubation were enrolled. Patients presented at least one or more risk factors for difficult airway. The patients were randomly allocated at a 1:1 ratio to one of two groups: group L, FOI with tongue root holder, or group C, standard FOI. Orotracheal FOI was performed after commencement of anesthesia. The jaw thrust maneuver was applied in both groups to facilitate advancement of the fiberoptic bronchoscope. The primary endpoint was the feasibility of FOI. The secondary endpoints were number of attempts, time to intubation, and airway clearance at the soft palate and epiglottis levels.

Results

The FOI was achieved in all 150 patients in group L, significantly higher than that in group C (100% vs 95.3%; P = 0.015). Less attempts of intubation were made in group L (P = 0.039). Mean time to successful intubation on the first attempt was shorter in group L (P < 0.001). The mean times to view the vocal cord and carina were also shorter in group L (P = 0.011 and P < 0.001, respectively). Airway clearance was better in group L at both the soft palate and the glottis levels (P = 0.010 and P = 0.038, respectively).

Conclusions

This study shows that FOI is feasible with the newly introduced, self-designed, “tongue root holder” device, when combined with the jaw thrust maneuver in patients with risk factors for difficult airway. The device also provides better airway clearance, less intubation attempts, and shorter time to intubation at first attempt.

Clinical relevance

Fiberoptic bronchoscope has been the gold standard for routine management of difficult airway. A technique to open the airway is introduced to reduce the incidence rate of upper airway obstruction.

  相似文献   
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