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91.
The young age of onset and frequently intractable nature of seizures associated with Sturge-Weber syndrome (SWS) have been well-reported in large studies. However, many clinicians also anecdotally describe prolonged but sporadic seizure clusters. Over a 5-year period, 77 children and adults with SWS and at least one reported seizure were referred to and evaluated at the Hunter Nelson Sturge-Weber Center at the Kennedy Krieger Institute. The median age of seizure onset was 6 months with 43 (56%) presenting <1 year of age. Age at seizure onset ≤6 months was associated with increased hemiparesis, but not seizures. A characteristic pattern of clustering, intense seizures followed by prolonged seizure-free periods was reported in 30 (39%), but was not associated with worse prognosis. This seizure pattern appears to be common with SWS and leads to difficult treatment decisions, especially in regard to the timing of potential surgical resection. 相似文献
92.
目的:基于中医传承辅助系统软件,分析各医家治疗荨麻疹的用药经验。方法收集《实用中医美容金方》《皮肤病名家验案精选》《古今名医临证实录丛书之皮肤病》中治疗荨麻疹的病案,采用关联规则apriori算法、复杂系统熵聚类等无监督数据挖掘方法,分析处方中药物的使用频次及药物之间的关联规则、处方规律。结果对筛选出来的138首处方进行分析,处方中218味药物的使用频次在20次以上者有20味,其中防风的使用频次最高。按照药物组合出现频次由高到低的顺序,药物间的关联规则排在前4位的分别是“防风-蝉蜕”“防风-荆芥”“防风-赤芍”“荆芥-蝉蜕”,同时挖掘出30个核心药物组合和14首新处方。结论基于中医传承辅助系统平台开展的中药治疗荨麻疹的数据挖掘和用药规律研究,既为临床治疗荨麻疹提供了有效指导,同时也为治疗荨麻疹的新药研发提供依据。 相似文献
93.
A culster analysis was performed on 78 cases of Alzheimer's disease (AD) to identify possible pathological subtypes of the disease. Data on 47 neuropathological variables, inculding features of the gross brain and the density and distribution of senile plaques (SP) and neurofibrillary tangles (NFT) were used to describe each case. Cluster analysis is a multivariate statistical method which combines together in groups, AD cases with the most similar neuropathological characteristics. The majority of cases (83%) were clustered into five such groups. The analysis suggested that an initial division of the 78 cases could be made into two major groups: (1) a large group (68%) in which the distribution of SP and NFT was restricted to a relatively small number of brain regions, and (2) a smaller group (15%) in which the lesions were more widely disseminated throughout the neocortex. Each of these groups could be subdivided on the degree of capillary amyloid angiopathy (CAA) present. In addition, those cases with a restricted development of SP/NFT and CAA could be divided further into an early and a late onset form. Familial AD cases did not cluster as a separate group but were either distributed between four of the five groups or were cases with unique combinations of pathological features not closely related to any of the groups. It was concluded that multivariate statistical methods may be of value in the classification of AD into subtypes. 相似文献
94.
目的:探讨杨博良先生治疗痢疾的用药经验。方法收集杨博良先生治疗痢疾的处方,在建立数据库的基础上,采用关联规则apriori算法、复杂系统熵聚类等无监督数据挖掘方法开展研究。结果治疗痢疾处方常用药物包括茯苓、法半夏、煨葛根等,核心药物组合包括“茯苓-黄芩-牡丹皮”“车前子-法半夏-六神曲”“木香炭-大黄炭-荷叶”等,新处方包括“车前子-法半夏-六神曲-生地炭-制香附”等。结论杨博良先生治疗痢疾经验丰富,多用清热燥湿和利水渗湿之品。 相似文献
95.
目的:探讨常用补气类中成药组方规律。方法:收录《新编国家中成药》中的补气类中成药处方,采用关联规则apriori算法和复杂系统熵聚类等方法,确定处方中药物的使用频次及药物之间的关联规则等。结果:高频次药物包括黄芪、当归、熟地黄、茯苓、白术等;高频次药物组合包括"当归、黄芪""熟地黄、当归""白芍、当归"等;置信度较高的关联规则包括"川芎、熟地黄-当归""白芍、熟地黄-当归"等。结论:处方用药中除常见的补气类中药外,尚包括具有养阴、生津、补血作用的部分补益药及其他类药物。 相似文献
96.
Yasunori Yamaguchi Kayo Inaba Jun Kawai Takuma Kato Shinji Nakamura Kazuko Uno Shigeru Muramatsu 《Cancer science》1989,80(2):141-149
T cells prepared from tumor (Meth A)-bearing mice were cocultured with homologous tumor cells and splenic dendritic cells to enrich tumor-specific T cells by the separation of clusters. T blasts generated from clusters were capable of inhibiting the in vivo tumor cell growth. The culture supernatant of clustering cells (CLSN) was effective in activating macrophages (MØ) to be cytostatic and cytocidal against tumor cells. Moreover, it was found that CLSN contains at least 3 distinct factors; one was identified as interferon-γ (IFN-γ), and the others are so far unidentified, but one acts synergistically with IFN-γ, possibly as the second signal, and the other cooperates with lipopolysaccharide but not with IFN-γ. We propose that the tumor-specific T cells secrete soluble mediators which cooperate with each other in MØ activation against tumor cells. 相似文献
97.
目的调查某院心脏大血管外科重症监护病房(下简称心外ICU)聚集性碳青霉烯类耐药肠杆菌科细菌(CRE)感染事件,为医院感染防控提供依据。方法对南京医科大学第一附属医院心外ICU 2019年6月-7月检出CRE的患者进行流行病学调查,给予控制措施,评价防控效果。结果该病区在2019年6-7月出现5例患者检出CRE共9株,其中4例患者为医院感染,1例患者为CRE定植,CRE医院感染例次率高于4-5月,差异有统计学意义(P<0.05)。9株CRE中8株病原菌为肺炎克雷伯菌(药敏谱一致),1株为大肠埃细菌。CRE来源分析77.78%(7/9)来自于心外ICU本身。共采集标本60份,包括水池区域24份、A床床单元16份、B床床单元8份、C床床单元4份、护理移动掌上电脑(PAD)和标本传输物流系统各4份。共10个位点的标本检测出CRE,其中CRE显色平板培养出9株CRE,麦康凯平板培养出2株CRE。采取综合控制措施结合针对性加强清洁消毒,复查未检测出CRE。控制后的5个月CRE检出及感染数量下降,效果显著。结论CRE显色平板结合麦康凯平板在CRE流行病学调查中可更有效且全面的培养出CRE,通过环境采样明确具体定植位点,并进行针对性干预,可高效去除CRE在环境中的定植。 相似文献
98.
Concept factorization (CF) is a variant of non-negative matrix factorization (NMF). In CF, each concept is represented by a linear combination of data points, and each data point is represented by a linear combination of concepts. More specifically, each concept is represented by more than one data point with different weights, and each data point carries various weights called membership to represent their degrees belonging to that concept. However, CF is actually an unsupervised method without making use of prior information of the data. In this paper, we propose a novel semi-supervised concept factorization method, called Pairwise Constrained Concept Factorization (PCCF), which incorporates pairwise constraints into the CF framework. We expect that data points which have pairwise must-link constraints should have the same class label as much as possible, while data points with pairwise cannot-link constraints will have different class labels as much as possible. Due to the incorporation of the pairwise constraints, the learning quality of the CF has been significantly enhanced. Experimental results show the effectiveness of our proposed novel method in comparison to the state-of-the-art algorithms on several real world applications. 相似文献
99.
目的 了解福建省大田县居民心血管病(CVD)危险因素分布、聚集及其与发病的关系,为制定本地区CVD防控策略和措施提供科学依据。方法 基于国家心血管病高危人群早期筛查与综合干预项目大田县项目点2018年数据,分析CVD常见危险因素(吸烟S、饮酒A、超重Ov、肥胖Ob、高血压H、糖尿病G、血脂异常D)的聚集特征;并通过logistic回归分别分析常见危险因素聚集个数及聚集组合与CVD患病的关系。结果 共纳入13 838名35~75岁常住居民的筛查数据,CVD患病率为1.6%,男性(2.4%)高于女性(1.0%)(P<0.001),随年龄增加呈增高趋势(P趋势<0.001)。检出率前3位的CVD常见危险因素为Ov(38.7%)、H(36.7%)、S(22.2%)。具有至少1个CVD常见危险因素者的占比为77.7%,其中具有1个、2个和≥3个CVD常见危险因素者分别占34.1%、26.8%和16.8%;男性、农民、年龄≥55岁者常见危险因素聚集个数较多。控制人口学特征后,与无常见危险因素者相比,具有2个和≥3个常见危险因素者患CVD的风险增加,OR(95%CI)分别为1.6(1.0~2.6)和2.0(1.2~2.1); CVD患病风险较高的常见危险因素组合为DHGS、DHS、DG,OR(95%CI)分别为11.7(1.9~71.7)、9.1(2.1~39.7)和7.5(1.5~36.9)。结论 大田县居民CVD危险因素检出率与聚集程度较高,尤其是男性、农民、年龄≥55岁者。多个危险因素聚集使CVD患病风险骤增,尤其是包含D、H的组合。 相似文献
100.
《Medical image analysis》2014,18(3):591-604
Labeling a histopathology image as having cancerous regions or not is a critical task in cancer diagnosis; it is also clinically important to segment the cancer tissues and cluster them into various classes. Existing supervised approaches for image classification and segmentation require detailed manual annotations for the cancer pixels, which are time-consuming to obtain. In this paper, we propose a new learning method, multiple clustered instance learning (MCIL) (along the line of weakly supervised learning) for histopathology image segmentation. The proposed MCIL method simultaneously performs image-level classification (cancer vs. non-cancer image), medical image segmentation (cancer vs. non-cancer tissue), and patch-level clustering (different classes). We embed the clustering concept into the multiple instance learning (MIL) setting and derive a principled solution to performing the above three tasks in an integrated framework. In addition, we introduce contextual constraints as a prior for MCIL, which further reduces the ambiguity in MIL. Experimental results on histopathology colon cancer images and cytology images demonstrate the great advantage of MCIL over the competing methods. 相似文献