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961.
目的分析肝硬化合并结核病患者的临床特征,为该类患者的治疗提供参考。方法回顾性分析2014年9月至2017年7月于浙江大学医学院附属第一医院住院的肝硬化合并结核病患者的相关资料,总结患者的临床特征。结果共收治68例肝硬化合并结核病患者,其中男性50例(73.5%),女性18例(26.5%),平均年龄(59.9±13.7)岁。在所有患者中,肝硬化最常见的原因是HBV感染(46例,67.7%)和酒精(9例,13.2%)。肺结核(43例)、结核性腹膜炎(13例)、结核性胸膜炎(12例)是最常见的结核类型,此外骨关节结核、结核性脑膜炎、结核性心包炎、泌尿系结核、肠结核、淋巴结结核均可见。该类患者常见临床表现为乏力、腹胀,出现发热的患者不足半数,有盗汗表现的更为罕见。结论肝硬化患者并发结核后可使病情复杂化,增加治疗难度。此外部分患者临床表现不典型,需提高警惕,避免漏诊。  相似文献   
962.
长非编码RNA(long non-coding RNAs, lncRNAs)是一类转录本长度大于200个核苷酸,不具有蛋白质编码功能的非编码RNA(non-coding RNA, ncRNA)。人类基因组中,ncRNA基因占比超过90%,数量远大于蛋白质编码基因。作为生物大分子,lncRNA具有特定的初级和高级结构,在基因表达调控等生物学进程中发挥着特有的功能。lncRNA数量多,结构各异,因此鉴定和表征新的lncRNA,探索其结构和功能,是当前基因研究领域的热点之一。在临床疾病机制研究中,大量结果表明,lncRNA与临床疾病发生发展,特别是肿瘤的发生发展具有密切的相关性。伴随着后基因组学时代基因鉴定和功能探索方法的不断进步,探索lncRNA在疾病发生中的功能及表达变化,深入解锁lncRNA在疾病发生中涉及的分子机制,将为疾病早期预防、诊断和预后提供有效参考。基于以上的研究大背景,本文对lncRNA的定义、基因鉴定的策略和方法,高级结构检测及其对应的生物学功能,以及lncRNA的分类进行了阐述;另一方面,基于lncRNA与肿瘤发生发展的密切关系,本文以经典抑癌基因p53为切入点,对多种p53相关的lncRNA在结直肠癌(colorectal cancer, CRC)发生发展中的作用进行了归纳小结,阐述了lncRNA在结直肠癌中的表达变化、涉及的分子互作机制和信号通路,对其作为分子标志物在临床中的应用潜力进行了评估。我们乐观地认为,作为生物分子标志物,lncRNA将为包括癌症在内的疾病治疗提供全新、精准和个性化的分子靶点。  相似文献   
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This study investigated the effect of adult associated cues of the multicolored Asian ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae) on the foraging behavior of the aphid parasitoid, Aphidius gifuensis Ashmead (Hymenoptera: Aphididae) with three assays: 1) whole aphid leaf-disc with H. axyridis tracks; 2) aphid leaf-disc with only half contaminated with H. axyridis tracks; 3) aphid leaf-discs without H. axyridis tracks. Foraging behavior of A. gifuensis was recorded using the Observer® XT 11 and EthoVsion® XT 12. In addition, functional responses of A. gifuensis in patches with or without H. axyridis cues were also tested. Aphidius gifuensis females preferred oviposition in arenas where no adult tracks of H. axyridis were present. However, no significant difference between functional responses of A. gifuensis foraging in plants with and without H. axyridis cues was detected. Our study suggests that H. axyridis associated cues could influence the foraging behavior and activity of A. gifuensis under laboratory conditions. On the other hand, the foraging efficiency of A. gifuensis was not significantly affected by H. axyridis walking tracks in a single plant system. Aphidius gifuensis might exhibit flexible behavioral responses to predator associated cues. The risk of intraguild interactions and the possibility of mitigating such risks for parasitoids are important components for ultimately determining the compatibility of biological control agents.  相似文献   
967.
Oak (Quercus spp.) and hornbeam (Carpinus spp.) are one of dominant tree species in East Asian temperate broad leaf deciduous forests and many insect species, including more than 65% of Lepidoptera species, feed on these trees. We sampled lepidopteran caterpillars from two 0.1 ha plots in a temperate forest to investigate the role of dominant trees (oaks and hornbeams) in herbivore community. In total, we identified 738 caterpillars from 223 Lepidopteran species on 34 tree species. Most caterpillar species were from species-rich families such as Geometridae 25% (56 spp.), Noctuidae, and Tortricidae. After excluding dominant trees, plant-herbivore network analyses showed increased network specialization and nestedness and decreased generality and vulnerability. These results suggest that oaks and hornbeams support a large Lepidopteran herbivore community, and co-occurring plant species support diverse but specific herbivores. Geographical distribution and plant community are closely related to diversity of the herbivore community. Future work is needed to investigate the likelihood that specialist herbivores become relatively more abundant in the forest as oaks are succeeded by hornbeams.  相似文献   
968.
The dysfunction of left atrial appendage (LAA) is prone to form thrombus when atrial fibrillation (AF) sustained more than 48 h. Traditional 2D-TEE (transesophageal echocardiography) can not accurate evaluate the function of LAA. The purpose of this study is to analyze the relationship of LAA function parameters and thrombus formation in patients with non-valvular atrial fibrillation (NVAF) by real-time three-dimensional transesophageal echocardiography (RT-3D-TEE). High risk patients can be identified according to the characteristics of ultrasonic index in patients with left atrial appendage thrombosis, which has important clinical value and significance in the risk assessment, guiding treatment and judging prognosis. We examined the relationship between the echocardiographic parameters of LAA function and the incidence of thrombus in 102 NVAF patients. They underwent RT-3D-TEE and left atrial appendage thrombus (LAAT)/severe spontaneous echocardiographic contrast (SSEC) was found in 67 patients (thrombus group) but absent in the remaining 35 patients (non-thrombus group). After measured by QLAB software, the LAA functional parameters were significantly associated with LAAT/SEC formation. Univariate analysis indicated that AF time, LAD, LVEF, LAA-OAmax, LAAVmax, LAAVI and LAAEF demonstrated a positive association (P < 0.05). However, logistic regression analysis identified that AF time (OR:1.73, P < 0.05)、LAAEF (OR:4.09, P < 0.01)and LAAVI (OR:3.28, P < 0.01) were independent predictors of LAAT/SSEC. In patients with nonvalvular atrial fibrillation, echocardiographic parameters of LAA function are significantly associated with LAAT/SSEC.  相似文献   
969.
With the development of genomics, the update of modern imaging technology and the advent of artificial intelligence and big data, the surgical treatment of gastric cancer has gradually stepped into precision medicine. Precision surgery treatment of gastric cancer is based on accurate molecular typing and staging using modern molecular diagnostic technology and imaging, and the formulation of precise and individualized surgical treatment plans, with the concept of minimally invasive and accelerated rehabilitation surgery running through it. For intermediate-stage gastric cancer, we have adopted a comprehensive treatment approach including traditional radiotherapy and chemotherapy, targeted therapy and immunotherapy. Utilize artificial intelligence and big data technology to improve the standardization and interconnectivity of specialty data and realize the transformation of evidence-based medicine. Promoting the standardization, standardization and individualization of gastric cancer surgical treatment, providing patients with precise diagnosis and treatment, and further improving patients'' prognosis are the opportunities and challenges in the development of gastric cancer surgery.  相似文献   
970.
BackgroundWe investigated the relationship between genetic alterations and 18F-FDG PET/CT findings in head and neck squamous cell carcinoma (HNSC).MethodsUsing mRNA-sequences of HNSC samples (480 patients) from the Cancer Genome Atlas (TCGA) portal, gene coexpression networks were constructed via a weighted correlation network analysis (WGCNA) algorithm, and their association with the tumor-to-blood signal ratio on 18F-FDG PET/CT data (21 patients) was explored. An elastic-net regression model was developed to estimate the PET tumor-to-blood ratio from the gene networks and to derive an FDG signature score (FDGSS). The FDGSS was evaluated with regard to clinical variables and general mutational profiles, as well as alterations to oncogenic signaling pathways.FindingsThe FDGSS values differed across clinical stages (p = 0.027), HPV-status (p< 0.001), and molecular subtypes of HNSC (p< 0.001). Multivariate Cox regression demonstrated that FDGSS was an independent predictor for overall (p = 0.019) and progression-free survival (p = 0.024). FDGSS positively correlated with total mutation rate (p = 0.016), aneuploidy (p < 0.001), and somatic copy number alteration scores (p < 0.001). CDKN2A in the cell cycle pathway (q = 0.014) and the TP53 gene in the TP53 pathway (q = 0.005) showed significant differences between high and low FDGSS patients.ConclusionFDGSS based on the gene coexpression network was associated with the mutational landscape of HNSC. 18F-FDG PET/CT is therefore a valuable tool for the in vivo imaging of these cancers, being able to visualize the glucose metabolism of the tumor and allow inferences to be made on the underlying genetic alterations in the tumor.  相似文献   
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