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81.
绢毛蔷薇果实的化学成分   总被引:16,自引:0,他引:16  
目的:研究绢毛蔷薇果实的化学成分。方法:将醇提取物用H2O溶解,EtOAc萃取,经柱色谱分离纯化,通过波谱分析并结合化学转化鉴定化合物。结果:从该植物果实中分离、鉴定了6个化合物:euscaphic acid 3,4-monoacetonide (1), euscaphic acid (2), 4-O-β-D-吡喃葡糖基没食子酸甲酯(3),槲皮素(4),齐墩果酸(5),豆甾醇(6)。结论:1是新化合物,3为首次从植物中分离得到。  相似文献   
82.
牙周炎是一种以牙周袋形成和牙槽骨吸收为特征的炎症性疾病,是40岁以上成人牙齿脱落的主要原因之一。牙周组织产生的龈沟液可以一定程度的揭示牙周的状态,其中的微小RNA (miRNA)的表达水平会根据牙周炎症的发展发生改变,可以作为牙周诊断的指标之一。miR-146a及miR-223是牙周炎进展中表达水平显著变化的miRNA,它们是目前利用龈沟液miRNA对牙周炎诊断最有潜力的生物标志物。不同miRNA可以通过调控牙周炎信号通路的不同阶段发挥作用,如通过细菌脂多糖与Toll样受体的结合、核因子κB配体信号通路及炎症因子的释放等过程调控牙周炎症进程。本文就牙周炎龈沟液中miRNA的表达差异及调控机制作一综述,以期为龈沟液miRNA准确诊断牙周炎提供新思路和新进展。  相似文献   
83.
BackgroundThe prevalence of sleep‐disordered breathing (SDB) is closely related to the severity of heart failure (HF), and the severity of HF is different in patients with HF of different etiologies. Hypothesis: This study aimed to explore the prevalence of SDB in patients with HFof different etiologies.MethodsHospitalized HF patients were consecutively enrolled. All patients underwent portable overnight cardiorespiratory polygraphy. Patients were divided into five groups according to the etiology of HF: ischemic, hypertensive, myocardial, valvular, and arrhythmic. The prevalence of SDB and clinical data was compared among the five groups.ResultsIn total, 248 patients were enrolled in this study. The prevalence of SDB in HF was 70.6%, with the prevalence of obstructive sleep apnea (OSA) at 47.6% and central sleep apnea (CSA) at 23.0%. Patients were divided into five groups: ischemic, hypertensive, myocardial, valvular, and arrhythmic. The prevalence of SDB among the five groups was 75.3%, 81.4%, 77.8%, 51.9%, and 58.5% (p = .014), respectively. The prevalence of OSA among the five groups was 42.7%, 72.1%, 36.1%, 37.0%, and 49.1% (p = .009), whereas the CSA was 32.6%, 9.3%, 41.7%, 14.8%, and 9.4% (p < .001), respectively.ConclusionsSDB is common in HF patients. The prevalence and types of SDB varied in HF with different etiologies, which may be related to the different severities of HF. SDB was highly prevalent in patients with ischemic, hypertensive, and myocardial HF. Hypertensive HF patients were mainly complicated with OSA, while myocardial HF patients were mainly complicated with CSA. Both conditions were highly prevalent in ischemic HF patients. The prevalence of SDB was relatively low in valvular and arrhythmic HF patients, and OSA was the main type.  相似文献   
84.
In order to study the influence of brace failure on the seismic response of concentrically braced frames and the improvement of the residual structure’s resistance to collapse due to reserve capacity, a series of concentrically braced frame prototypes with different story numbers is designed. A matrix of six finite-element concentrically braced-frame (CBF) models is established, which is varied by the number of stories and the level of reserve capacities. Accuracy of the numerical model is verified by comparing the responses of the shaking-table test of the concentrically braced frames, under 10 different working conditions. Then, a nonlinear time-history analysis, considering brace failure in one specified story, is carried out. The results show that the story-drift angle of the failure story as well as its adjacent stories increases greatly in the ideal pinned model. The above phenomenon is particularly serious, when the failure occurs at the top or bottom of the structure. With the reserve capacity brought by column continuity, and the semi-rigid rotation capacity of the beam-to-column and column-to-base connections are taken into consideration, the increase in story-drift angle caused by the brace failure is effectively reduced. However, the inherent reserve capacity has little influence on the dynamic characteristics of concentrically braced frames in the elastic stage.  相似文献   
85.
IL‐27 is an anti‐inflammatory cytokine that triggers enhanced antitumor immunity, particularly cytotoxic T lymphocyte responses. In the present study, we sought to develop IL‐27 into a therapeutic adjutant for adoptive T cell therapy using our well‐established models. We have found that IL‐27 directly improved the survival status and cytotoxicity of adoptive OT‐1 CD8+ T cells in vitro and in vivo. Meanwhile, IL‐27 treatment programs memory T cell differentiation in CD8+ T cells, characterized by upregulation of genes associated with T cell memory differentiation (T‐bet, Eomes, Blimp1, and Ly6C). Additionally, we engineered the adoptive OT‐1 CD8+ T cells to deliver IL‐27. In mice, the established tumors treated with OT‐1 CD8+ T‐IL‐27 were completely rejected, which demonstrated that IL‐27 delivered via tumor antigen–specific T cells enhances adoptive T cells’ cancer immunity. To our knowledge, this is the first application of CD8+ T cells as a vehicle to deliver IL‐27 to treat tumors. Thus, this study demonstrates IL‐27 is a feasible approach for enhancing CD8+ T cells’ antitumor immunity and can be used as a therapeutic adjutant for T cell adoptive transfer to treat cancer.  相似文献   
86.
Diffuse Large B Cell Lymphoma (DLBCL), the most common form of blood cancer. The genetic and clinical heterogeneity of DLBCL poses a major barrier to diagnosis and treatment. Hence, we aim to identify potential biomarkers for DLBCL.Differentially expressed genes were screened between DLBCL and the corresponding normal tissues. Kyoto Encyclopedia of Genes and Genomes and Gene oncology analyses were performed to obtain an insight into these differentially expressed genes. PPI network was constructed to identify hub genes. survival analysis was applied to evaluate the prognostic value of those hub genes. DNA methylation analysis was implemented to explore the epigenetic dysregulation of genes in DLBCL.In this study, Kinesin family member 23 (KIF23) showed higher expression in DLBCL and was identified as a risk factor in DLBCL. The immunohistochemistry experiment further confirmed this finding. Subsequently, the univariate and multivariate analysis indicated that KIF23 might be an independent adverse factor in DLBCL. Upregulation of KIF23 might be a risk factor for the overall survival of patients who received an R-CHOP regimen, in late-stage, whatever with or without extranodal sites. Higher expression of KIF23 also significantly reduced 3, 5, 10-year overall survival. Furthermore, functional enrichment analyses (Kyoto Encyclopedia of Genes and Genomes, Gene oncology, and Gene Set Enrichment Analysis) showed that KIF23 was mainly involved in cell cycle, nuclear division, PI3K/AKT/mTOR, TGF-beta, and Wnt/beta-catenin pathway in DLBCL. Finally, results of DNA methylation analysis indicated that hypomethylation in KIF23''s promoter region might be the result of its higher expression in DLBCL.The findings of this study suggested that KIF23 is a potential biomarker for the diagnosis and prognosis of DLBCL. However, further studies were needed to validate these findings.  相似文献   
87.
Heteroatom-doped carbon materials used in supercapacitors are low in cost and demonstrate extraordinary performance. Here, ethylenediamine tetraacetic acid (EDTA) with intrinsic N and O elements is selected as a raw material for the preparation of heteroatom self-doped porous carbon. Furthermore, N/O self-doped porous carbon with a large surface area has been successfully prepared using K2CO3 as the activator. The derived sample with a 1 : 2 molar ratio of EDTA to K2CO3 (EK-2) demonstrates a porous structure, rich defects, a large surface area of 2057 m2 g−1 and a micropore volume of 0.25 cm3 g−1. Benefiting from high N content (2.89 at%) and O content (10.75 at%), EK-2 exhibits superior performance, including high capacitance of 325 F g−1 at 1 A g−1 and outstanding cycling stability with 96.8% retention after 8000 cycles at 10 A g−1, which strongly confirms its immense potential toward many applications. Additionally, the maximum energy density of EK-2 reaches was 17.01 W h kg−1 at a power density of 350 W kg−1 in a two-electrode system. This facile and versatile strategy provides a scalable approach for the batch synthesis of N/O co-doped carbonaceous electrode materials for energy storage.

Heteroatom-doped carbon materials used in supercapacitors are low in cost and demonstrate extraordinary performance.  相似文献   
88.
Porcine circovirus-like virus (PCLV) is a member of circovirus that contains a single-strand DNA genome, which may be one of the pathogens that causes diarrheal symptoms in pigs. The Rep protein encoded by the genome of PCLV may be responsible for viral genome replication. The development of serological detection methods for PCLV is of great necessity for clinical diagnosis, as well as epidemiological investigations. Therefore, this study attempted to build an indirect enzyme-linked immunosorbent assay (ELISA) to examine antibodies against PCLV based on the His-tagged recombinant Rep protein. Full-length PCLV Rep protein was induced and expressed in E. coli and was purified as an antigen to establish an ELISA detection kit. The purified Rep protein was used to inject into mice to produce specific antibodies. There was no cross-reaction of Rep-based ELISA with antisera against other porcine viruses. The intra-assay and inter-assay coefficient variations (CVs) were 0.644–8.211% and 0.859–7.246%, respectively, indicating good repeatability. The non-cross-reaction with TGEV, PRRSV and PCV2 testing showed high sensitivity and high specificity for this ELISA assay. A total of 1593 serum samples collected from different pig farms in Jiangxi Province were tested for anti-PCLV Rep antibodies, and 284 (17.83%) of the 1593 samples were Rep antibody positive. Altogether, the indirect ELISA detection tool developed in this study could be applied to examine serum of PCLV antibodies with good repeatability, high sensitivity and high specificity. In addition, field sample detection results suggested that the PCLV antibody has a low prevalence in pig populations in Jiangxi Province of China.  相似文献   
89.
目的 比较修复楔状缺损时制备固位形及不同粘结剂对临床疗效的影响.方法 选择口内至少4颗楔状缺损的患者89例,609颗患牙,同一患者分别采用四种方法修复患牙(固位形+两步法自酸蚀牙本质粘结系统Clearfil SE Bond;固位形+一步法自酸蚀牙本质粘结系统iBond;无固位形+两步法自酸蚀牙本质粘结系统Clearfil SE Bond;无固位形+一步法自酸蚀牙本质粘结系统iBond),采用自身对照的方法进行为期1年的临床观察.结果 固位形组的成功率明显高于无固位形组,两者差异有统计学意义;无固位形组中两步法自酸蚀牙本质粘结系统Clearfil SE Bond组的成功率高于一步法自酸蚀牙本质粘结系统iBond组,两者差异有统计学意义,但二者在边缘密闭性和术后敏感方面差异没有统计学意义.结论 修复楔状缺损时,制备固位形有助于提高疗效;两步法自酸蚀牙本质粘结系统Clearfil SE Bond较一步法自酸蚀牙本质粘结系统iBond具有更高的粘结强度.  相似文献   
90.
Potential use of liposome for polycationic colistin is hindered by their phospholipid membrane permeability. In this study, liposomes were modified with sodium cholesteryl sulphate (Chol-SO4?) for improving the colistin loading by enhancing the colistin-bilayer electrostatic attraction. We have evaluated two liposomes: colistin-entrapped liposome of Chol-SO4? (CCL) and coated Chol-SO4?/colistin complex liposome (CCCL). In comparison with CCL which formed large aggregates at Chol-SO4?/colistin charge ratio below 2:1, CCCL showed a smaller size less dependent on the charge ratio, probably arising from more colistin entrapped on the inner leaflet of bilayer. Both liposomes exhibited significantly increased entrapment efficiency as compared with the liposome without Chol-SO4?. But colistin released upon dilution, implying free transfer of colistin through bilayers. Pharmacokinetics results showed the approximately four-fold increase in the plasma AUC0–8?h for CCCL and CCL as compared with colistin solution, showing potential benefit for infectious target localisation by prolonging the systemic circulation of colistin.  相似文献   
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