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Common scab (CS) caused by Streptomyces spp. is a significant soilborne potato disease that results in tremendous economic losses globally. Identification of CS-associated species of the genus Streptomyces can enhance understanding of the genetic variation of these bacterial species and is necessary for the control of this epidemic disease. The present study isolated Streptomyces strain 6-2-1(1) from scabby potatoes in Keshan County, Heilongjiang Province, China. PCR analysis confirmed that the strain harbored the characteristic Streptomyces pathogenicity island (PAI) genes (txtA, txtAB, nec1, and tomA). Pathogenicity assays proved that the strain caused typical scab lesions on potato tuber surfaces and necrosis on radish seedlings and potato slices. Subsequently, the strain was systemically characterized at morphological, physiological, biochemical, and phylogenetic levels. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 6-2-1(1) shared 99.86% sequence similarity with Streptomyces rhizophilus JR-41T, isolated initially from bamboo in rhizospheric soil in Korea. PCR amplification followed by Sanger sequencing of the 16S rRNA gene of 164 scabby potato samples collected in Heilongjiang Province from 2019 to 2020 demonstrated that approximately 2% of the tested samples were infected with S. rhizophilus. Taken together, these results demonstrate that S. rhizophilus is capable of causing potato CS disease and may pose a potential challenge to potato production in Heilongjiang Province of China.

本文报道一例腹型偏头痛患者的诊治过程。患者表现为周期性腹痛伴恶心、呕吐，完善电子胃镜、全消化道造影、腹盆CT等检查后未能发现明显器质性病变；追问病史：患者偶尔头痛，母亲患偏头痛20年，考虑腹型偏头痛可能，予诊断性治疗后患者症状发作明显减少。该类患者极易误诊为肠易激综合征或急腹症，分享本例诊治体会旨在提高内科医生对腹型偏头痛的认知，重视病史收集，在充分除外其他器质性疾病基础上应考虑该病，诊断性治疗是明确诊断的重要手段。.

The present work cast a complex Mg-6Gd-3Y-0.5Zr alloy component in a polybenzylic ether phenolic resin (PEP-SET) sand mold using by differential pressure casting. Microstructural characterization was carried out on the castings in the states of as-cast, solution treatment and aging treatment. Their mechanical properties were examined at elevated temperatures. The studied Mg alloy showed noticeably high tensile strengths up to 473 K, followed by a significant decrease with further increasing the testing temperatures. Its mechanical properties at elevated temperatures were compared with those of WE43 alloy fabricated under identical casting conditions.

To evaluate the storage stability of metabolites from actinomycetesThe fermentation supernatant ofAfter the fermentation supernatant ofThe active mollcuscicidal ingredients of the

To test the activity of aromatic pyrrole-based compounds against cercariae ofA series of aromatic pyrrole-based compounds were synthesized using 4-benzyl-5-(trifluoromethyl)-1H-pyrrole-3-nitrile as the lead compound. The synthesized compounds were prepared into solutions at concentrations of 10.00, 1.00, 0.10, 0.01 mg/L, and the activity of these solutions againstA total of 7 aromatic pyrrole-based compounds were successfully synthesized. Treatment with compounds 102, 104 and 106 at a concentration of 0.01 mg/L for 30 min killed allCompound 104 achieves a 100% mortality rate against

自2003年在家族性高胆固醇血症家系中鉴定出致病基因前蛋白转换酶枯草溶菌素9（PCSK9）以来，以PCSK9为靶点的抑制剂研发进展迅速。目前PCSK9抑制剂作为一类新型降脂药物已被广泛应用于包括家族性高胆固醇血症在内的广大心血管疾病患者。近年来研究表明，PCSK9抑制剂除了血脂调控作用外，还有潜在的抗炎、抗动脉和静脉血栓形成以及增强肿瘤免疫抑制剂疗效等功能，本文就PCSK9抑制剂多效性的相关研究进展进行总结，为PCSK9抑制剂的临床应用提供新的思路。.

To compare the effects of levo-praziquantel (L-PZQ) and dextro-praziquantel (D-PZQ) on the proliferation and activation of the human hepatic stellate cell line LX-2LX-2 cells were stimulated with transforming growth factor-β (TGF-β). LX-2 cell proliferation was measured using the CCK-8 assay after 24 h stimulation with 0 to 50 μg/mL concentrations of praziquantel, and the gene and protein expression of type Ⅰ collagen (collagen Ⅰ), type Ⅲ collagen (collagen Ⅲ) and α-smooth muscle actin (α-SMA) was quantified in LX-2 cells using quantitative real-time PCR (qPCR) and Western blotting assays 24 h and 48 h following stimulation with 15 μg/mL praziquantel to detect LX-2 cell activation.There were significant differences in the survival rate of LX-2 cells between L-PZQ and D-PZQ treatments at all concentrations (Both L-PZQ and D-PZQ inhibit the proliferation and activation of LX-2 cells, and D-PZQ shows a higher inhibitory activity than L-PZQ.

This article describes the experience with the endoscopically assisted fixation of the customized total temporomandibular joint (TMJ) prosthesis in TMJ Yang's system only through a modified preauricular approach. Twenty patients (23 joints) treated with the custom-made total TMJ prosthesis were retrospectively recruited. An endoscopically assisted technique was used through a modified preauricular approach to fix the mandibular component for all these patients. These reconstructions were evaluated by surgical records, clinical examinations, and radiographic observations. All patients had successful fixation of the prosthesis. No patient had permanent weakness of the facial nerve and malocclusion or any other severe complications. The mean operative time was 111 min per joint (range, 85-133 min). The average surgical bleeding was 195 ml per side. The mean follow-up period was 16.2 months (range, 5-32 months). The mean scores were 8.3 for surgical satisfaction and 9.2 for scar healing evaluation. All patients experienced positive clinical outcomes, with a mean 75.2% reduction in pain and 53.7% increase in mouth opening with significant differences (P

Misfit stresses in the γ″-strengthened Ni-base superalloy Inconel 718 were calculated from the measured constrained misfit strain using Eshelby’s inclusion method. The constrained misfit strains of the γ″ precipitates were measured using neutron diffraction at various temperatures with the aid of the stress-induced variant selection method. Eshelby tensor was calculated using the expressions for the case of anisotropic matrix given by Mura. Results show the presence of significant compressive misfit stresses in the γ″ precipitates with an anisotropic distribution, namely 3.0 GPa along the habit plane and 1.7 GPa along the plane normal direction at room temperature, and 2.0 and 1.2 GPa at 664 °C. The decrease in misfit stresses was due to the decrease in stiffness and the different coefficients of thermal expansion of the γ and γ″ phases. The average internal stresses in the γ matrix due to lattice misfit were found to be ~ 329 MPa at room temperature and ~ 186 MPa at 664 °C in tension. The possibility of relieving such high levels of misfit stresses in precipitates by loss of coherency during continued growth of precipitates is also discussed.

心房颤动（房颤）显著增加卒中风险，抗凝治疗是房颤综合管理的重要组成部分。我国房颤患者抗凝比例仍然很低，尤其是高龄老年人。该文在新近发表文献的基础上，重点阐述了包括超高龄在内的高龄房颤患者抗凝治疗的净获益；同时强调了与相对年轻的房颤患者相比，非维生素K拮抗剂口服抗凝药在高龄非瓣膜性房颤患者抗凝中同样具有优势；抗血小板治疗不应单独用于高龄房颤患者的卒中预防，左心耳封堵术在该人群中的应用需严格掌握适应证。.

The plastic forming of titanium alloy tubes at room temperature exhibits strong anisotropy, low elongation, and large deformation resistance. Numerical control warm bending assisted forming technology can improve the stability of the titanium alloy tube bending process, increase the bending limit and reduce the springback angle. This technology promotes the wide application of high-precision titanium alloy bent tubes in many high-end fields such as aerospace, shipbuilding, chemical industry, and military industry. However, the titanium alloy tube bending at high temperatures involves complex material rheological behavior and microstructure characteristics. The coupling relationship between the stress-strain properties of the material and the temperature field makes it difficult to predict the springback behavior of titanium alloy tubes after warm bending. In this paper, based on the mechanical behavior of titanium alloy tubes at high temperatures, a constitutive model of titanium alloy suitable for local heating is improved. The theoretical model of springback for warm rotary draw bending of titanium alloy tube is established. The influence of warm bending strategies on the springback of bending is studied. The theoretical model is verified by establishing a thermal-mechanical coupling finite element model for the whole process of warm bending under the state of heat balance. The results show that the bending springback theory based on the modified John-Cook model can accurately simulate the temperature change of titanium alloy tube section, adapt to local heating strategies and provide high prediction accuracy of bending springback.

新型冠状病毒肺炎（COVID-19）是传播速度快，影响范围广的传染病。北京协和医院援鄂抗疫国家医疗队（协和医疗队）在武汉抗疫工作中，注重对危重型COVID-19患者的人文关怀，具体措施包括：（1）发展叙事能力，充分理解疾病给患者家庭带来的痛苦；（2）提升医患沟通的人文内涵；（3）尊重患者感受，注意维护患者人格尊严；（4）通过沟通、共情、反思等方法实施医患共同决策。协和医疗队的经验表明，人文关怀在救治危重型COVID-19患者过程中是不可或缺的。.

心电图是医学史上逾百年而经久不衰的检查和诊断技术之一。心电图机是国内临床最基本的医疗设备，甚至目前已成为可自购的穿戴设备。然而，百年前第一台心电图机在中国的诞生和发展，凝聚了众多中国医学先驱及协和前辈们的艰辛心血和不懈努力，也见证了中国近代史的变革、动乱及新生。本文提供了详实的历史资料和照片，追溯了北京协和医院心电图百年发展史，以及心电先驱们对中国心电图机的使用、改造及普及作出的卓越贡献。.

In this paper, a simple all-fiber switchable orbital angular momentum (OAM) mode-locked laser is demonstrated. The laser is mainly composed of a single-mode fiber Bragg grating (FBG), a two-mode fiber Bragg grating (TM-FBG), a two-mode circulator, and a nonlinear polarization rotation system. The coupling properties of the TM-FBG are verified, and an OAM mode-locked laser with switchable topological charges of −1, 0, and 1 is realized. When the pump power is 462 mW, the output powers of the fundamental mode and OAM±1 mode-locked lasers are 9.750 and 2.707 mW, respectively. Their repetition rates are both 10.16 MHz, and the signal-to-noise ratios are 60 and 59 dB. When the pump power is increased to 774 mW, the mode-locked laser can operate in the single-pulse, double-pulse, and triple-pulse states. Their output powers are 5.1, 7.4, and 10.1 mW, respectively. The OAM mode purity higher than 98.9% is experimentally realized.

遗传因素对冠心病的发生发展具有重要作用。近年来，基于大规模人群的全基因组关联分析研究（GWAS）和罕见变异关联分析研究（RVAS）揭示了人类基因组中大量的与冠心病关联的遗传位点和部分致病基因。同时，这些冠心病遗传学的研究成果也在快速地向临床应用转化，为寻找冠心病的药物靶点、指导个体化治疗带来了新思路，具有广阔的发展前景。该文对冠心病遗传学领域的三大热点问题做一综述，包括冠心病多基因遗传风险的评估与个体化治疗、孟德尔随机化研究对冠心病治疗靶点的筛选验证以及冠心病新基因靶点的发现与靶向治疗药物的研发。.

近年来，冠心病的年轻化趋势愈发显著。许多不同种类的遗传性疾病能够引起早发冠心病及其他临床表现与之相似的冠状动脉疾病，包括遗传性脂质代谢紊乱、血管壁结构及功能障碍、血液高凝状态及加速衰老等。本文汇总已知能引起早发冠状动脉疾病的21种遗传性疾病的临床特点、遗传机制、心血管风险的研究证据以及治疗的特殊性。这些遗传性疾病中相当一部分属于罕见病，在临床中需要与一般的早发冠心病鉴别，促进精准的个体化诊疗。.

Polycrystalline Ni-base superalloy Inconel 718 derives the strengthening mainly from Ni3Nb γ″ phase. To investigate the evolution of lattice spacing of γ″ precipitates, in situ neutron diffraction experiments were performed during aging heat treatment of two Inconel 718 bar samples at 780 °C for 8 hours. One sample was aged with a negligible applied stress (5 MPa) and the other with an applied tensile stress of 300 MPa. The diffraction data demonstrate three stages of lattice spacing evolution due to compositional and morphological changes during aging. (1) Stage I, the γ lattice spacing decreases isotropically in the first hour of aging as the composition changes. (2) Stage II, the γ lattice spacing decreases and the γ″ lattice spacing increases between 1 and 5 hours of aging, at this stage compositional change on the lattice evolution weakens with aging time and the morphological change becomes comparable. (3) Stage III, as aging proceeds, compositional change is negligible, while morphological change is dominant; the γ lattice spacing decreases in the longitudinal direction but increases in the transverse direction; in contrast, the converse occurs in γ″ lattice spacing evolution.

Special processing, viz ultrasonic vibration-assisted laser sintering of diamonds was studied. This process would eliminate the drawbacks pertaining to existing super-hard grinding wheels. The composite process fully utilized the odds of laser sintering and ultrasonic vibration to homogenize the structure and reduce residual stresses. Diamond particles were added to a 45 steel matrix using a Ni–Cr alloy via ultrasonic vibration-assisted laser sintering in argon. Metallographic microscopy, and were used to examine the microstructure of a Ni–Cr alloy and abrasive diamond particle bonding interface microstructure, Raman spectrometry was applied to evaluate residual stresses. Acoustic flow and cavitation effects generated by ultrasonic vibration refine crystal grains in the cladding layer and the microstructure is more homogeneous than the microstructure without ultrasonic treatment. A Cr3C2 layer formed on the surface of abrasive diamond particles enhances the bonding ability of a Ni–Cr alloy to diamond, which ensures the diamond isolation and protection, ultrasonic vibration reduces residual stresses inside abrasive diamond particles.

心力衰竭（心衰）患者住院率高、预后不良，是心血管病领域备受关注的严重临床综合征。近年来涌现出一批新型的治疗心衰的药物，改变着心衰药物治疗的模式。沙库巴曲缬沙坦已成为心衰治疗的基石，院内早期应用可减少心衰患者近期心血管不良事件，长期应用可维持甚至逆转心室重构，射血分数保留的心衰患者亦具有潜在获益。钠-葡萄糖协同转运蛋白2抑制剂和胰高血糖素样肽-1受体激动剂具有心血管保护作用，具有降低心衰患者糖尿病发病率、延缓糖尿病肾病进展、减少心血管事件发生等多重获益。在心衰标准治疗基础上加用新型可溶性鸟苷酸环化酶激动剂维利西呱可进一步降低不良事件的发生率，是心衰药物治疗的重要补充。心肌肌球蛋白抑制剂马瓦卡坦可通过降低心肌收缩力改善肥厚型心肌病患者心功能，有望改写其治疗模式。.