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71.
应用超声影像技术预测胎儿体重的综述   总被引:12,自引:0,他引:12  
随着超声影像技术的发展,超声检查成为预测胎儿体重的重要手段。国内外学者用多元回归的方法提出了许多图表和公式。人工神经网络是以神经的结构和生理为基础模拟人类思维的计算机人工智能技术。对复杂的、非线性信息处理有其独特的优势。在预测胎儿体重这一领域,人工神经网络的方法比传统的回归分析法有着更大的优势。  相似文献   
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回顾了近年来部分基于人工智能的面瘫识别及评估研究。研究方法可分为基于人工选取患者面部图像特征值和基于神经网络和患者面部图像的面瘫评估研究两大类。分析表明,人工选取特征值的方法适合小样本量的情况,但对面瘫相邻评级的分类效果有待进一步优化。而神经网络的方法能够相对较好地区分面瘫邻级,但对样本量有较高要求。两种方法均有不错的前景,人工选取与评估量表相关性更强的特征,而共同的发展方向可能是提取时间域特征,从而达到提升面瘫评估准确率的目的。  相似文献   
74.
王馨培  王子玉  傅强  杜超  巩传勇  王兵 《中草药》2021,52(2):437-446
目的 采用网络药理学和多中心临床数据探讨清肺承气汤治疗腹腔感染所致急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)的作用机制.方法 通过中药系统药理学分析平台(Traditional Chinese Medicine Systems Pharmacology Dat...  相似文献   
75.
BackgroundNetwork analysis has been used to explore the interplay between psychopathology and functioning in psychosis, but no study has used dedicated statistical techniques to focus on the bridge symptoms connecting these domains. The current study aims to estimate the network of depressive, negative, and positive symptoms, general psychopathology, and real-world functioning in people with first-episode schizophrenia or schizophreniform disorder, focusing on bridge nodes.MethodsBaseline data from the OPTiMiSE trial were analyzed. The sample included 446 participants (age 40.0 ± 10.9 years, 70% males). The network was estimated with a Gaussian graphical model, using scores on individual items of the positive and negative syndrome scale (PANSS), the Calgary depression scale for schizophrenia, and the personal and social performance scale. Stability, strength centrality, expected influence (EI), predictability, and bridge centrality statistics were computed. The top 20% scoring nodes on bridge strength were selected as bridge nodes.ResultsNodes from different rating scales assessing similar psychopathological and functioning constructs tended to cluster together in the estimated network. The most central nodes (EI) were Delusions, Emotional Withdrawal, Depression, and Depressed Mood. Bridge nodes included Depression, Conceptual Disorganization, Active Social Avoidance, Delusions, Stereotyped Thinking, Poor Impulse Control, Guilty Feelings, Unusual Thought Content, and Hostility. Most of the bridge nodes belonged to the general psychopathology subscale of the PANSS. Depression (G6) was the bridge node with the highest value.ConclusionsThe current study provides novel insights for understanding the complex phenotype of psychotic disorders and the mechanisms underlying the development and maintenance of comorbidity and functional impairment after psychosis onset.  相似文献   
76.
BACKGROUNDThe effect of chronic kidney disease (CKD) on the outcomes of colorectal cancer (CRC) patients after primary CRC surgery is controversial.AIMTo analyze whether CKD had specific effect on the outcomes after CRC surgery.METHODSWe searched the PubMed, Embase, Cochrane Library databases and CNKI, from inception to March 14, 2022. Newcastle-Ottawa Scale was used for the quality assessment in this meta-analysis, and we used RevMan 5.3 was used for data analysis.RESULTSA total of nine studies including 47771 patients were eligible for this meta-analysis. No significant difference was found in terms of overall postoperative complications [odds ratio (OR) = 1.78, 95%CI: 0.64-4.94, P = 0.27]. We analyzed the specific complications and found that the CKD group had higher rates of pulmonary infection (OR = 2.70, 95%CI: 1.82-4.00, P < 0.01), cardiovascular complications (OR = 3.39, 95%CI: 2.34-4.91, P < 0.01) and short-term death (OR = 3.01, 95%CI: 2.20-4.11, P < 0.01). After pooling the hazard ratio (HR), the CKD group had worse overall survival (OS) (HR = 1.51, 95%CI: 1.04-2.20, P = 0.03). We performed subgroup analyses of the dialysis and non-dialysis groups, and no significant difference was found in the non-dialysis group (HR = 1.20, 95%CI: 0.98-1.47, P = 0.08). The dialysis group had worse OS (HR = 3.36, 95%CI: 1.92-5.50, P < 0.01) than the non-dialysis group. The CKD group had worse disease-free survival (DFS) (HR = 1.41, 95%CI: 1.12-1.78, P < 0.01), and in the subgroup analysis of the dialysis and non-dialysis groups, no significant difference was found in the non-dialysis group (HR = 1.27, 95%CI: 0.97-1.66, P = 0.08). The dialysis group had worse OS (HR = 1.95, 95%CI: 1.23-3.10, P < 0.01) than the non-dialysis group.CONCLUSIONPreexisting CKD was associated with higher rates of pulmonary infection, higher rates of short-term death, and worse OS and poorer DFS following CRC surgery.  相似文献   
77.
A COVID-19 outbreak occurred among Cameron Peak Fire responders in Colorado, USA, during August 2020–January 2021. The Cameron Peak Fire was the largest recorded wildfire in Colorado history, lasting August–December 2020. At least 6,123 responders were involved, including 1,260 firefighters in 63 crews who mobilized to the fire camps. A total of 79 COVID-19 cases were identified among responders, and 273 close contacts were quarantined. State and local public health investigated the outbreak and coordinated with wildfire management teams to prevent disease spread. We performed whole-genome sequencing and applied social network analysis to visualize clusters and transmission dynamics. Phylogenetic analysis identified 8 lineages among sequenced specimens, implying multiple introductions. Social network analysis identified spread between and within crews. Strategies such as implementing symptom screening and testing of arriving responders, educating responders about overlapping symptoms of smoke inhalation and COVID-19, improving physical distancing of crews, and encouraging vaccinations are recommended.  相似文献   
78.
BackgroundChronic obstructive pulmonary disease (COPD) is a complex and heterogeneous condition, in which taking into consideration clinical phenotypes and multimorbidity is relevant to disease management. Network analysis, a procedure designed to study complex systems, allows to represent connections between the distinct features found in COPD.MethodsNetwork analysis was applied to a cohort of patients with COPD in order to explore the degree of connectivity between different diseases, taking into account the presence of two phenotypic traits commonly used to categorize patients in clinical practice: chronic bronchitis (CB+/CB) and the history of previous severe exacerbations (Ex+/Ex). The strength of association between diseases was quantified using the correlation coefficient Phi (ɸ).ResultsA total of 1726 patients were included, and 91 possible links between 14 diseases were established. Although the four phenotypically defined groups presented a similar underlying comorbidity pattern, with special relevance for cardiovascular diseases and/or risk factors, classifying patients according to the presence or absence of CB implied differences between groups in network density (mean ɸ: 0.098 in the CB group and 0.050 in the CB+ group). In contrast, between‐group differences in network density were small and of questionable significance when classifying patients according to prior exacerbation history (mean ɸ: 0.082 among Ex subjects and 0.072 in the Ex+ group). The degree of connectivity of any given disease with the rest of the network also varied depending on the selected phenotypic trait. The classification of patients according to the CB/CB+ groups revealed significant differences between groups in the degree of conectivity between comorbidities. On the other side, grouping the patients according to the Ex/Ex+ trait did not disclose differences in connectivity between network nodes (diseases).ConclusionsThe multimorbidity network of a patient with COPD differs according to the underlying clinical characteristics, suggesting that the connections linking comorbidities between them vary for different phenotypes and that the clinical heterogeneity of COPD could influence the expression of latent multimorbidity. Network analysis has the potential to delve into the interactions between COPD clinical traits and comorbidities and is a promising tool to investigate possible specific biological pathways that modulate multimorbidity patterns.  相似文献   
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目的评价替吉奥联合奥沙利铂(SOX方案)对比替吉奥联合顺铂(SP方案)治疗晚期胃癌(AGC)的疗效及安全性。 方法在PubMed、Embase、Web of Science、中国期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)、万方数据库、维普中文科技期刊数据库中检索2022年7月前公开发表的有关替吉奥联合奥沙利铂(SOX组)对比替吉奥联合顺铂(SP组)治疗AGC的相关研究,按照Cochrane Handbook 5.1的临床试验质量评价标准对文献进行质量评价,采用RevMan 5.4软件进行Meta分析。 结果共有14篇2 650例AGC患者纳入研究,其中SOX组1 334例,SP组1 316例。与SP组比较,SOX组的总生存期(HR=0.87,95% CI:0.78~0.97,P=0.01)、无进展生存期(HR=0.87,95% CI:0.78~0.97,P=0.01)、完全缓解(OR=1.43,95% CI:1.02~2.00,P=0.04)、部分缓解(OR=1.64,95% CI:1.18~2.29,P=0.003)、疾病进展(OR=0.55,95% CI:0.34~0.87,P=0.01)、疾病控制率(OR=1.64,95% CI:1.04~2.56,P=0.03)和疾病稳定(OR=0.67,95% CI:0.53~0.83,P=0.000 4)方面比较,差异均有统计学意义,而两组客观有效率差异无统计学意义(OR=1.57,95% CI:0.85~2.90,P=0.15)。安全性方面,3级及以上不良反应中,SOX组白细胞减少(OR=0.20,95% CI:0.13~0.30,P<0.000 01)、贫血(OR=0.52,95% CI:0.32~0.86,P=0.01)、肌酐升高(OR=0.21,95% CI:0.07~0.61,P=0.004)的发生率更低,而周围感觉神经病(OR=10.64,95% CI:1.85~61.10,P=0.008)的发生率更高。 结论SOX方案可提高AGC的治疗有效率,改善无进展生存期和总生存期,但可能增加周围感觉神经病的发生率。  相似文献   
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