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1.
目的 多样的环境因素使得不同产地栽培滇重楼的化学成分也丰富多样,不同居群栽培滇重楼的甾体皂苷类成分具有很大的差异,多源数据融合分析能更全面的表征药材化学信息,建立一个高效而准确的产地鉴别模型,为其资源合理开发利用提供依据。方法 以来自云南和四川的8个产地(保山、楚雄、大理、红河、丽江、成都、文山、玉溪)共366份栽培滇重楼根茎为实验材料,采集其傅里叶变换近红外光谱(FT-NIR)和衰减全反射-傅里叶变换中红外光谱(ATR-FTMIR)数据。采用Kennard-Stone算法将不同产地的样品分为2/3的训练集和1/3的预测集,基于4种特征变量提取方法(CARS、VIP、SPA、SO-Covsel)结合2种数据融合策略(低级数据融合和中级数据融合),建立偏最小二乘产地判别分析模型。根据模型参数交叉验证均方根误差(RMSECV)和预测均方根误差(RMSEP)评估模型的稳定性,模型训练集和预测集准确率(ACC)评估模型分类性能。结果 近红外光谱和中红外光谱均能反应不同产地栽培滇重楼的化学成分差异,在中级数据融合中,基于VIP和SPA提取的特征变量建立的模型正确率均大于94%。相较于中级数据融合,低级数据融合模型得到了最为满意的结果,其预测集分类正确率达到100%。结论 根据近红外和中红外数据建立的低级数据融合PLS-DA模型,能够用于栽培滇重楼的产地鉴别分析。  相似文献   
2.
肺癌是我国最常见且死亡率最高的恶性肿瘤之一,随着表皮生长因子受体(EGFR)、间变性淋巴瘤激酶(ALK)及活性氧1(ROS1)等驱动基因及其相应分子靶向药物的出现,晚期非小细胞肺癌的治疗和预后发生了革命性变化。此外,一些少见新型驱动基因融合,包括神经调节蛋白1(NRG1)、神经营养酪氨酸受体激酶(NTRK)和转染重排因子(RET),正逐渐发展成为全身性治疗选择。然而,这些罕见新型融合驱动基因在NSCLC脑转移中的作用机制,以及优化控制和预防脑转移的意义人们所知甚少。因此,本文就近几年罕见驱动基因融合在NSCLC脑转移中的研究进行综述。  相似文献   
3.
We have been experiencing multiple waves of the coronavirus disease 2019 (COVID-19) pandemic. With these unprecedented waves, we have entered into an era of ‘new normal’. This pandemic has enforced us to rethink the very basics of childhood learning: Habits, health etiquette, and hygiene. Rehabilitation has immense importance during this pandemic considering a few aspects. Multidisciplinary COVID-19 rehabilitation clinics are essential to address the demand. The equitable distribution of COVID-19 rehabilitation services for differently-abled individuals during the pandemic is an important aspect. Rehabilitation needs identification and further studies on various rehabilitation interventions are among the key unmet future research needs.  相似文献   
4.
目的探讨微创后路腰椎椎间融合术(MIS-PLIF)和传统开放PLIF对腰椎退行性疾病(LDD)远期疗效及安全性的影响。方法 2011年1月-2014年12月收治LDD患者182例,其中96例采用传统开放PLIF治疗(PLIF组),86例采用MIS-PLIF治疗(MIS-PLIF组)。比较2组腰椎矢状位参数、多裂肌横截面积及萎缩率、融合率、疼痛视觉模拟量表(VAS)评分、日本骨科学会(JOA)评分、Oswestry功能障碍指数(ODI)及术后并发症发生情况,分析多裂肌萎缩率与顽固性腰背痛的相关性。结果 2组术后各随访时间点椎间隙高度恢复值和节段性前凸角恢复值差异均无统计学意义(P > 0.05)。2组术后1年腰椎前凸角恢复值差异无统计学意义(P > 0.05);但术后5年和末次随访时,MIS-PLIF组腰椎前凸角恢复值显著高于PLIF组,差异均有统计学意义(P < 0.05)。MIS-PLIF组术后各随访时间点多裂肌横截面积大于PLIF组,多裂肌萎缩率低于PLIF组,差异均有统计学意义(P < 0.05)。2组术后随访6个月融合率差异无统计学意义(P > 0.05)。2组术后各随访时间点下肢痛VAS评分差异无统计学意义(P > 0.05);MIS-PLIF组术后各随访时间点腰痛VAS评分、JOA评分及ODI均优于PLIF组,差异有统计学意义(P < 0.05)。MIS-PLIF组顽固性腰背痛发生率显著低于PLIF组,差异有统计学意义(P < 0.05)。合并顽固性腰背痛患者多裂肌萎缩率高于未合并顽固性腰背痛的患者,差异有统计学意义(P < 0.05)。结论术后多裂肌萎缩可能是导致顽固性腰背痛的重要原因,相较于传统开放PLIF,MIS-PLIF治疗LDD能够更有效地保持腰椎生理曲度,改善肢体活动功能,降低多裂肌萎缩程度,有助于避免顽固性腰背痛的发生。  相似文献   
5.
《Diagnostic Histopathology》2021,27(12):506-518
Recent discovery of new disease-defining molecular alterations and development of novel targeted therapies has dramatically changed the classification and management of uterine mesenchymal neoplasms. This review discusses diagnostic updates in endometrial stromal sarcoma, PEComa, uterine tumor resembling ovarian sex cord tumor (UTROSCT), inflammatory myofibroblastic tumor, NTRK fusion uterine sarcoma, COL1A1-PDGFB fusion sarcoma, and SMARC-deficient uterine sarcoma. Key clinical, morphologic, immunophenotypic, and molecular features are reviewed, with emphasis on common differential diagnoses and pitfalls, and their impact on prognosis or management. Where applicable, the role of novel targeted therapies is discussed. A stepwise approach to uterine mesenchymal neoplasms can achieve a proper diagnosis and guide appropriate clinical management in most cases. Nonetheless, given the rarity of these tumors, their overlapping pathologic features, and rapid evolution in their classification and management, we advocate a low threshold for diagnostic consultation.  相似文献   
6.
目的 探讨长链非编码RNA(lncRNA)FTX表达水平与脑胶质瘤病人预后的相关性。方法 前瞻性收集2016年1月~2018年1月手术切除的脑胶质瘤88例(46例获得瘤旁组织),采用实时逆转录PCR检测lncRNA FTX表达水平,以脑胶质瘤组织lncRNA FTX表达水平均值为界分为高表达组(n=57)和低表达组(n=31)。术后随访3年,主要观察指标为无进展生存期、总生存期。结果 脑胶质瘤组织lncRNA FTX表达水平[(7.54±2.15)]明显高于瘤旁组织[(2.65±0.69);P<0.001]。多因素Cox比例回归风险模型分析显示,lncRNA FTX高表达是脑胶质瘤生存预后不良的独立危险因素(RR=1.589;95% CI 1.004~2.515;P=0.048)。生存曲线分析显示,高表达组无进展生存期(15.10个月)和总生存期(20.24个月)较低表达组(分别为18.96和25.53个月)明显缩短(P<0.05)。结论 脑胶质瘤lncRNA FTX呈高表达,与病人不良生存预后有关。  相似文献   
7.
Aluminum matrix composites (AMC) are of great interest and importance as high-performance materials with enhanced mechanical properties. Al2O3 is a commonly used reinforcement in AMCs fabricated by means of various technological methods, including casting and sintering. Selective laser melting (SLM) is a suitable modern method of the fabrication of net-shape fully dense parts from AMC with alumina. The main results, achievements, and difficulties of SLM applied to AMCs with alumina are discussed in this review and compared with conventional methods. It was shown that the initial powder preparation, namely the particle size distribution, sphericity, and thorough mixing, affected the final microstructure and properties of SLMed materials drastically. The distribution of reinforcing particles tends to consolidate the near-melting pool-edges process because of pushing by the liquid–solid interface during the solidification process that is a common problem of various fabrication methods. The achievement of an homogeneous distribution was shown to be possible through both the thorough mixing of the initial powders and the precise optimization of SLM parameters. The strength of the AMCs fabricated by the SLM method was relatively low compared with materials produced by conventional methods, while for superior relative densities of more than 99%, hardness and tribological properties were obtained, making SLM a promising method for the Al-based matrix composites with Al2O3.  相似文献   
8.
9.
BackgroundHip-to-calcaneus (HC) view is a whole-leg standing view that can visualize the hindfoot in detail. The aim of this study was to investigate the reliability and validity of tibiocalcaneal angle in HC view (H-TCA) by comparing it with that in long axial view (L-TCA). We also verified whether periarticular knee alignment parameters, measured conventionally in whole-leg standing radiography, could be measured in HC view.MethodSixty healthy volunteers and 61 patients with medial knee osteoarthritis were included. H-TCA was measured by two examiners in the healthy group, and intra-class correlation coefficients (ICCs) were evaluated. H-TCA and L-TCA were then measured in the healthy and osteoarthritis groups and correlated. Finally, we measured hip–knee–ankle angle, mechanical axis deviation ratio, mechanical lateral distal femoral angle, medial proximal tibial angle, and joint-line convergence angle in HC view and conventional whole-leg standing radiography to evaluate statistical differences and correlations.ResultsThe intra-observer and inter-observer ICCs were 0.86 and 0.76, respectively. Correlation coefficients (r) between H-TCA and L-TCA were r = 0.87 in healthy group and r = 0.81 in osteoarthritis group, indicating a strong positive correlation in both groups. There was no significant difference in periarticular knee alignment parameters between HC view and conventional whole-leg radiography.ConclusionsHindfoot evaluation in HC view showed high intra-observer and inter-observer reliabilities and strong positive correlation with TCA in long axial view. By using HC view before knee surgery, such as total knee arthroplasty, other necessary alignments can be evaluated simultaneously.  相似文献   
10.
ObjectiveWe report a low-grade endometrial stromal sarcoma (ESS) with a novel CDKN1A-JAZF1 fusion gene arising from abdominal wall endometrioma.Case reportA 40-year-old woman presented with a 5.5-cm abdominal wall mass juxtaposed to the postoperative scar of two cesarean sections. Histologically, the tumor exhibited obvious tongue-like protrusions into the surrounding tissue, showed spindle cells with multinodular growth pattern that occasionally rotate around small arteries. Immunohistochemically, the tumor cells were positive for CD10, estrogen receptor (ER), progesterone receptor (PR), negatively stained for smooth muscle actin (SMA), CD117, CyclinD1. In addition, a previously undescribed gene fusion between CDNK1A 5′ end of exon 1(NM_000389.5) and JAZF1 3′ end of exon 5 (NM_175,061,3) was reported in this case.ConclusionThis report of ESS suggesting that rapidly growing abdominal wall masses without menstruation-related should be promptly evaluated and treated aggressively. In addition, we have expanded the molecular landscape of low-grade ESS.  相似文献   
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