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101.
102.
甲状腺癌是内分泌系统常见的恶性肿瘤之一,其发病率呈逐年上升趋势。甲状腺癌以分化型甲状腺癌(differentiated thyroid carcinoma, DTC)为主,尽管多数DTC患者经规范化治疗后预后良好,但由于部分肿瘤的病理类型侵袭性较高或肿瘤组织分化程度较低,病情进展迅速导致患者总生存时间显著缩短。近年来,有关炎症与肿瘤之间相关性的研究越来越多,炎性微环境的改变在肿瘤发病机制中的作用逐渐被证实,更多的证据表明细胞因子可作为肿瘤的良恶性鉴别、预后判断提示及诊疗方案选择等的重要参考依据。本文就部分细胞因子在DTC诊疗中的应用进展进行论述,旨在为DTC的诊疗与预后判断等提供参考依据。  相似文献   
103.
Cutaneous histiocytoses constitute a heterogeneous group of diseases characterised by the cutaneous accumulation of cells with the cytological and phenotypic features of macrophages or dendritic cells. The clinical spectrum ranges from self-resolving, skin-limited conditions to severe, multiorgan disease with a high morbidity rate. Until recently, cutaneous histiocytoses were classified according to the immunophenotype of the pathological cells, with differentiation between Langerhans cell histiocytosis (LCH) [CD1a+, CD207 (langerin)+] and non-Langerhans cell histiocytosis (CD68+, CD163+, CD1a?, CD207?). Over the last 12 years, a number of new pathophysiological findings (in particular, molecular pathology results) regarding histiocytoses have contributed to a new classification based on molecular alterations, as well as on clinical and imaging characteristics and the phenotype. The most frequent entities in children are juvenile xanthogranuloma and LCH.  相似文献   
104.
Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.  相似文献   
105.
106.
目的探讨胆总管结石患者采用内镜逆行胰胆管造影术(ERCP)取石后同期开展胆道支架置入术或开展经内镜鼻胆管引流术(ENBD),对于防范并发症的价值。 方法按照前瞻性研究原则,选择2017年4月至2019年1月新疆医科大学第一附属医院收治的338例胆总管结石患者,随机分为支架组(170例)与引流组(168例)。两组患者均行ERCP治疗,其中引流组术后同期开展ENBD,支架组患者术后开展胆道支架置入术,对比两组患者腹痛评分、并发症发生情况及预后。 结果两组患者术后均未合并严重出血、穿孔或病死,结石完全清除率差异无统计学意义。与支架组相比,引流组术中胰腺管插管次数,术后4 h血淀粉酶水平、高淀粉酶血症、急性胰腺炎以及并发症总发生率更高,差异有统计学意义(P<0.05),术后24、48、72 h不同时点腹痛测评分值居更高水平(P<0.05)。 结论对于胆总管结石行ERCP治疗的患者,术后予以ENBD、胆道支架置入术的结石完全清除效果对比无明显差异,但胆道支架置入术更能降低术后并发症风险、缓解腹痛症状,患者获益更多。  相似文献   
107.
ObjectivesTo examine the impact of time to surgery (TTS) on survival among patients with stage I non-small cell lung cancer (NSCLC).MethodsAll patients in the Canadian province of Ontario with stage I NSCLC from 2007 to 2017 were included. A logistic regression identified the predictors of TTS and a flexible parametric model estimated survival rates based on TTS.ResultsOver the study period, 6428 patients with stage I NSCLC undergoing surgical resection were identified, of which 62.5% had TTS >28 days. Less than half these patients (40.8%) underwent open resection, with 19.3% undergoing open sublobar and 21.5% undergoing open lobectomy. Adenocarcinoma and squamous cell carcinoma tumors accounted for 33.3% and 22.0% of cases, respectively. The majority (85.6%) of patients lived in urban areas within 50 km of a regional cancer center (76.9%). Variables that predicted TTS >28 days include age and extent of resection. After adjustment for VATS vs. open resection, age, sex, frailty, year of diagnosis, histology of tumor, and extent of resection, the hazard ratio for TTS >28 days was 1.26 (95%CI:1.13–1.40), indicating a 26% increased risk of all-cause mortality (p < 0.0001). The highest 5-year survival was observed for patients with stage I disease undergoing resection within 28 days.ConclusionsThe present study found age and extent of resection to be associated with increased TTS. Importantly, patients with TTS >28 days had reduced long-term survival.  相似文献   
108.
Species identification of unknown biological samples is crucial for forensic applications, especially in cases of explosion, disaster accidents, and body mutilation after murdering, as well as poaching, illegal trade in endangered animals, and meat food fraud. In this study, we identified 60 volatile organic compounds (VOCs) in fresh skeletal muscle tissues of seven different animal species (cattle, sheep, pigs, rabbits, rats, chickens and carp) and a human dead body by headspace-gas-chromatography ion-mobility spectrometry (HS-GC-IMS), and compared their differences by retention time, drift time and molecular weight. The results showed that these VOCs formed different gallery plot fingerprints in the skeletal muscle tissues of the human dead body and seven animal species. Principal component analysis (PCA) showed significantly different fingerprints between these species, and these fingerprints maintained good stability between the species and within the same species. Some VOCs have high species specificity, while VOCs of human fresh muscle tissues from different individual sources have little difference, demonstrating that all tested muscle tissue samples could be distinguished based on different VOCs. HS-GC-IMS has proved to be a rapid, high-throughput, highly sensitive and specific species identification method, which can be used for forensic species identification in criminal cases and disaster accidents, as well as detection in the field of food safety, such as meat fraud and adulteration.  相似文献   
109.
淋巴管作为循环系统的重要组成部分之一,具有调节机体体液稳态,协助免疫监视和肠道脂质吸收等重要作用。淋巴管新生是机体生理和病理过程中维持脉管系统结构和功能正常的重要手段,淋巴管新生调控对于防治肿瘤、心血管等诸多疾病有着潜在的临床转化意义;淋巴回流功能则与关节炎症等疾病发病机制关系密切。在循环系统中,相较于中医药调控血管相关疾病的发病机制已取得很大进展,近年来对于淋巴管的研究则明显相对滞后。本文从中医药作用于淋巴管新生及回流功能角度对这一领域的研究进展作一综述,以期为临床上中医药治疗相关疾病提供新的思路与方法。  相似文献   
110.
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