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杨岩  肖佳妹  周晋  贺福元  曾慧杰  杨岩涛 《中草药》2020,51(8):2258-2266
在中医药现代化进程中,有效地结合现代科学技术手段对传统中医药进行更为合理的分析是一个重要研究方向。计算机科学技术与人工智能算法在中医药研究领域已取得长足发展,尤其是分类算法所具有的快速鉴别和分析能力,使其在复杂的中医药研究体系中发挥举足轻重的作用。对支持向量机分类算法及其结合其他算法在解决中医药相关领域问题方面及成果进行综述,以相关智能算法为基础探讨中医药研究过程中的诸多难题,为推动中医药现代化进程提供支撑。  相似文献   
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《Piel》2019,34(8):464-469
IntroductionTelangiectasia macularis eruptiva perstans (TMEP) is a rare cutaneous mastocytosis, characterised by erythematous and/or brown macula in which telangiectasia are identified. The diagnosis is based on the clinical state of the lesions and on histopathology; however dermoscopy is an important diagnostic tool, revealing a very characteristic reticular vascular pattern.MethodologyA clinical examination, dermatoscopy, photographic follow-up, and histological study were performed on 5 patients with erythematous brown spots on the neck and V of the neckline, and were seen in this Centre between 2008 and 2018. A polarised light dermatoscope was used on lesion and the skin around it. All patients had a 4 mm punch biopsy of the affected skin, and the slices were stained with haematoxylin-eosin and Giemsa.ResultsThe dermatoscopy of the 5 patients showed a retiform vascular pattern with surrounding and crossing yellow spots corresponding to the follicular sebaceous glands, with few hairs. The skin around the lesion did not show any of these changes. In all patients, biopsy with haematoxylin-eosin corroborated the diagnosis of mastocytosis type TMEP. The location of the disease in the 5 patients was in the neck and V of the neckline.ConclusionsDermatoscopy helps in the diagnosis of TMEP by demonstrating that the retiform telangiectatic vascular pattern is a constant finding in all affected patients, and this is supported by the dermoscopic-histological findings. It also makes it possible to differentiate with other erythematous skin disease, and with other disorders that dermatoscopically exhibit retiform patterns.  相似文献   
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《Clinical lung cancer》2020,21(6):534-544
BackgroundReliable prediction of progression patterns and failure sites for patients with stage IV lung adenocarcinoma is valuable for physicians to deliver personalized tyrosine kinase inhibitor (TKI) treatment.Patients and MethodsWe retrospectively enrolled 266 patients who had stage IV lung adenocarcinoma and received first-line TKI treatment from 2013 to 2017 in Shanghai Chest Hospital. The clinical characteristics at initial diagnosis, progression patterns, and failure sites were analyzed with the attempt to identify some predictive factors for progression patterns and failure sites.ResultsAmong all patients, 62.4% developed systemic progression, and 37.6% developed oligoprogression. Both cohorts had a median progression-free survival (PFS) of 9 months. The percentage of patients who developed original and distant failure was 39.1% and 60.9%, respectively. Patients with oligometastasis at initial diagnosis were more prone to develop oligoprogression (odds ratio [OR], 4.370; 95% confidence interval [CI], 1.881-10.151; P = .001), whereas pulmonary metastasis was negatively correlated with oligoprogression (OR, 0.567; 95% CI, 0.330-0.974; P = .04). Both oligometastasis diagnosis (OR, 2.959; 95% CI, 1.347-6.500; P = .007) and the maximum diameter of the primary lung lesion (threshold 3.25 cm: OR, 3.646; 95% CI, 2.041-6.515; P = .0001) were strong predictive factors for original failures. Osseous metastasis at initial diagnosis might be an indication for distant failure (OR, 0.536; 95% CI, 0.316-0.909; P = .021).ConclusionOver one-half of patients with stage IV lung adenocarcinoma receiving first-line TKI treatment developed systemic progression and distant failure. Metastasis patterns at initial diagnosis was the most important predictive factor for progression patterns and failure sites. The maximum diameter of the primary lung lesion and evidence of osseous metastasis were also found to be significant indicative factors for failure sites.  相似文献   
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目的:提升参威骨痹片的质量标准,初步探索其质量控制指标成分在批间含量差异较大的原因。方法:采用HPLC建立参威骨痹片的指纹图谱,以Diamonsil C18(4. 6 mm×250 mm,5μm)为色谱柱,流动相乙腈(A)-0. 1%磷酸水溶液(B)梯度洗脱(0~5 min,10%A;5~15 min,10%~12%A;15~30 min,12%~26%A;30~43 min,26%~31%A,43~50 min,31%~40%A,50~70 min,40%~55%A;70~84 min,55%~72. 5%A),检测波长230 nm。以共有峰为自变量绘制正交偏最小二乘法-判别分析-变量重要性投影(OPLS-DA-VIP)图,将共有峰对该制剂各批次间指纹图谱差异的贡献度量化,寻找差异较大的色谱峰,结合相关文献,筛选出与参威骨痹片临床适应症相关的成分并进行其含量测定的专属性试验,最终选定质控指标。通过HPLC-二极管阵列检测器(DAD)同时对本品及其生产过程中间体中质控指标进行测定,检测波长236,276,230,322 nm,其他条件同HPLC指纹图谱检测方法。结果:HPLC指纹图谱共标定了26个共有峰,各批次样品指纹图谱与对照指纹图谱的相似度均≥0. 950。优选出马钱苷酸、龙胆苦苷、芍药苷、蛇床子素为参威骨痹片的质控指标,四者的平均质量分数分别为161. 02,401. 80,255. 54,80. 68μg·g-1。结论:所建立的指纹图谱及多指标定量分析方法稳定、可靠,可用于参威骨痹片的质量控制。原料药批间质控指标成分含量差异和生产过程中间体的质控方法不够完善是引起该制剂批间质控指标成分含量差异较大的主要原因。  相似文献   
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经典名方泽泻汤的HPLC指纹图谱及多指标含量测定研究   总被引:2,自引:0,他引:2  
目的建立经典名方泽泻汤的HPLC指纹图谱,结合化学模式识别技术对其进行分析,并测定泽泻汤中3种成分23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的含量,为泽泻汤质量控制提供科学依据。方法采用Waters WAT054275C18色谱柱(250 mm×4.6 mm,5μm),以乙腈-水为流动相进行梯度洗脱,建立15批泽泻汤的HPLC指纹图谱,并采用"中药色谱指纹图谱相似度评价系统"、SPSS22.0及SIMCA14.1软件对15批泽泻汤的HPLC指纹图谱进行相似度评价及聚类分析(CA)、偏最小二乘判别分析(PLS-DA)等化学模式识别。同时测定23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的含量。结果建立了15批泽泻汤的HPLC指纹图谱,相似度均0.94,标定了18个共有峰,指认出3个色谱峰,分别为11号峰白术内酯Ⅲ、15号峰23-乙酰泽泻醇C、16号峰23-乙酰泽泻醇B,CA和PLS-DA将15批泽泻汤样品分为2类,同时15批泽泻汤中23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的质量分数分别为0.321~0.569、0.075~0.139、0.106~0.142 mg/g。结论 HPLC指纹图谱结合多成分同时测定的方法,快速、简便、重复性好,为泽泻汤及其制剂的质量评价提供参考。  相似文献   
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Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent (“where”), sequence of events (“when”), and the content of the experience itself (“what”). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection.  相似文献   
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总结了全国著名骨伤专家梁铁民教授的学术思想和正骨经验,简述了梁老生平。梁老学术思想表现在突出整体观念,主张辨证施术;注重调理气血,强调药物接续;重视望问切触量法五诊结合等三个方面。对于梁老正骨经验先进行了综合论述,进一步佐证其学术思想;后分别从小儿桡骨头半脱位、颈椎错位、胸腰椎小关节错位、肋骨骨折等梁老研究较深入和比较擅长的几个方面进行了阐述。特别是颈椎错位这种高难度高风险的手法操作,体现出梁老高超的手法技艺。  相似文献   
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