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151.
Rational design and construction of bifunctional electrocatalysts with excellent activity and durability is imperative for water splitting. Herein, a novel top‐down strategy to realize a hierarchical branched Mo‐doped sulfide/phosphide heterostructure (Mo‐Ni3S2/NixPy hollow nanorods), by partially phosphating Mo‐Ni3S2/NF flower clusters, is proposed. Benefitting from the optimized electronic structure configuration, hierarchical branched hollow nanorod structure, and abundant heterogeneous interfaces, the as‐obtained multisite Mo‐Ni3S2/NixPy/NF electrode has remarkable stability and bifunctional electrocatalytic activity in the hydrogen evolution reaction (HER)/oxygen evolution reaction (OER) in 1 m KOH solutions. It possesses an extremely low overpotential of 238 mV at the current density of 50 mA cm?2 for OER. Importantly, when assembled as anode and cathode simultaneously, it merely requires an ultralow cell voltage of 1.46 V to achieve the current density of 10 mA cm?2, with excellent durability for over 72 h, outperforming most of the reported Ni‐based bifunctional materials. Density functional theory results further confirm that the doped heterostructure can synergistically optimize Gibbs free energies of H and O‐containing intermediates (OH*, O*, and OOH*) during HER and OER processes, thus accelerating the catalytic kinetics of electrochemical water splitting. This work demonstrates the importance of the rational combination of metal doping and interface engineering for advanced catalytic materials.  相似文献   
152.
目的:了解妇科盆腔恶性肿瘤血常规变化及其临床意义。方法:以无锡市人民医院2018年1月~2019年3月收治的90例妇科盆腔恶性肿瘤患者作为病例组,同期住院的243例确诊为盆腔良性病变或妊娠状态的患者作为良性对照组,选取同期717名接受体检的成年女性作为健康对照组,对三组研究对象的血常规指标进行回顾性分析。结果:与健康对照组比较,良性对照组和病例组患者的嗜酸性粒细胞百分比(EO)、嗜酸性粒细胞计数(EO#)、红细胞压积(HCT)、血红蛋白水平(HGB)、淋巴细胞百分比(LY)、淋巴细胞计数(LY#)、红细胞平均血红蛋白浓度(MCHC)、血小板分布宽度(PDW)、红细胞计数(RBC)水平降低,单核细胞计数(MO#)、血小板平均体积(MPV)、中性粒细胞百分比(NE)、中性粒细胞计数(NE#)、红细胞分布宽度(RDW)、白细胞计数(WBC)水平升高;病例组患者EO、EO#、LY、LY#、MO#、MPV水平低于良性对照组,HCT、HBG、MCHC、PDW、NE、NE#、RDW水平高于良性对照组,同时,病例组患者的红细胞平均血红蛋白含量(MCH)、红细胞平均体积(MCV)水平高于健康对照组,健康对照组的MCH、MCV水平高于良性对照组,良性对照组患者的单核细胞百分比(MO)、血小板压积(PCT)水平高于健康对照组,健康对照组的MO、PCT水平高于病例组,差异均有统计学意义(P0.05)。Logistic多元回归分析结果显示,LY#、MO#、MCHC、RDW、MCH、MCV与盆腔恶性肿瘤的发生具有相关性(P0.05)。ROC曲线分析结果显示,在各项血常规指标中,MCV诊断妇产科盆腔恶性肿瘤的曲线下面积(AUC)最高,为0.683。结论:盆腔恶性肿瘤患者的血常规指标与良性病变患者和健康人群均存在差异,部分指标与恶性肿瘤的发生具有独立相关性。  相似文献   
153.
Wang  Lixia  Zhu  Fan  Yang  Huansheng  Li  Jianzhong  Li  Yali  Ding  Xueqin  Xiong  Xia  Ji  Fengjie  Zhou  Hanlin  Yin  Yulong 《中国科学:生命科学英文版》2020,63(2):259-268
Epidermal growth factor(EGF) has been shown to improve piglet intestinal morphology and epithelial recovery. In an attempt to further understand the mechanisms behind these improvements, this study tested the hypothesis that dietary EGF may affect intestinal morphology by stimulating the proliferation and differentiation of enterocytes in weaning piglets. In piglets receiving200 μg kg–1 EGF, crypt depth and villus height increased(P0.05). Adding 400 μg kg–1 EGF increased villus height-to-crypt depth ratio(P0.05), but reduced crypt depth(P0.05). Dietary supplementation with 200 μg kg–1 EGF significantly increased the number of Ki67-positive cells(P0.01) and tended to increase the mRNA level of proliferating cell nuclear antigen(P0.10).However, this supplementation decreased the expression level of intestinal fatty acid-binding protein(P0.05). Piglets fed with400 μg kg–1 EGF had an increased mRNA level of intestinal alkaline phosphatase(P0.05). The phosphorylation of m TOR(mammalian target of rapamycin) was observed in the 200 μg kg–1 EGF group. These results suggest that dietary supplementation with a low level of EGF improved piglet intestinal morphology through stimulating the proliferation and differentiation of enterocytes, and the mTOR signaling pathway may partly be involved in this process.  相似文献   
154.
The jasmonic acid (JA) pathway plays crucial roles in plant defence against pathogens and herbivores. Rice stripe virus (RSV) is the type member of the genus Tenuivirus. It is transmitted by the small brown planthopper (SBPH) and causes damaging epidemics in East Asia. The role(s) that JA may play in the tripartite interaction against RSV, its host, and vector are poorly understood. Here, we found that the JA pathway was induced by RSV infection and played a defence role against RSV. The coat protein (CP) was the major viral component responsible for inducing the JA pathway. Methyl jasmonate treatment attracted SBPHs to feed on rice plants while a JA-deficient mutant was less attractive than wild-type rice. SBPHs showed an obvious preference for feeding on transgenic rice lines expressing RSV CP. Our results demonstrate that CP is an inducer of the JA pathway that activates plant defence against RSV while also attracting SBPHs to feed and benefitting viral transmission. This is the first report of the function of JA in the tripartite interaction between RSV, its host, and its vector.  相似文献   
155.
EDS1 (Enhanced Disease Susceptibility 1) plays a crucial role in both effector-triggered immunity activation and plant basal defence. However, whether pathogen effectors can target EDS1 or an EDS1-related pathway to manipulate immunity is rarely reported. In this study, we identified a Phytophthora capsici Avirulence Homolog (Avh) RxLR (Arg-any amino acid-Leu-Arg) effector PcAvh103 that interacts with EDS1. We demonstrated that PcAvh103 can facilitate P. capsici infection and is required for pathogen virulence. Furthermore, genetic evidence showed that PcAvh103 contributes to virulence through targeting EDS1. Finally, PcAvh103 specifically interacts with the lipase domain of EDS1 and can promote the disassociation of EDS1–PAD4 (Phytoalexin Deficient 4) complex in planta. Together, our results revealed that the P. capsici RxLR effector PcAvh103 targets host EDS1 to suppress plant immunity, probably through disrupting the EDS1–PAD4 immune signalling pathway.  相似文献   
156.
157.
Helicobacter pylori infection in children and adolescents differs in comparison to adults with respect to epidemiology, host responses, and disease manifestations. Furthermore, treatment options are limited in this population and antibiotic resistance rates continue to increase. Therefore, ongoing research is vital to understand disease pathogenesis and provide optimal management of children with infection. This review summarizes relevant publications from April 2019 to March 2020. Similar to adults, recent studies show a decreasing prevalence of infection in the pediatric population. Studies of pathogenesis investigated serum immune responses and the potential inverse association of infection and allergy. Several studies investigated the effect of H pylori and related inflammation on the gut microbiome. The recommendation of endoscopy‐based testing to identify the cause of symptoms and not just H pylori, reserving noninvasive UBT or stool antigen tests for post‐eradication follow‐up, was supported by the current literature.  相似文献   
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Sertoli cells (SCs) are presumed to be the center of testis differentiation because they provide both structural support and biological regulation for spermatogenesis. Previous studies suggest that SCs control germ cell (GC) count and Leydig cell (LC) development in mouse testes. However, the regulatory role of SCs on peritubular myoid (PTM) cell fate in fetal testis has not been clearly reported. Here, we employed Amh‐Cre; diphtheria toxin fragment A (DTA) mouse model to selectively ablate SCs from embryonic day (E) 14.5. Results found that SC ablation in the fetal stage caused the disruption of testis cords and the massive loss of GCs. Furthermore, the number of α‐smooth muscle actin‐labeled PTM cells was gradually decreased from E14.5 and almost lost at E18.5 in SC ablation testis. Interestingly, some Ki67 and 3β‐HSD double‐positive fetal LCs could be observed in Amh‐Cre; DTA testes at E16.5 and E18.5. Consistent with this phenomenon, the messenger RNA levels of Hsd3b1, Cyp11a1, Lhr, Star and the protein levels of 3β‐HSD and P450Scc were significantly elevated by SC ablation. SC ablation appears to induce ectopic proliferation of fetal LCs although the total LC number appeared reduced. Together, these findings bring us a better understanding of SCs’ central role in fetal testis development.  相似文献   
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