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81.
目的 基于Lasso回归和列线图构建并验证川崎病患儿对丙种球蛋白耐药的预测模型,以期为临床诊疗提供帮助。方法 回顾性收集2014年7月—2020年7月西南医科大学附属医院收治的474例川崎病患儿的临床资料,采用Lasso回归分析筛选重要的临床因素构建Nomogram模型,通过绘制受试者工作特征(ROC)曲线、Calibration校准曲线及DCA曲线验证模型的区分度、校准度及临床有效性。结果 共纳入474例患儿资料,其中339例作为训练集,135例作为验证集。Lasso回归分析显示,心脏表现、心外并发症、首剂静脉注射免疫球蛋白使用时间、中性粒细胞比例、红细胞分布宽度-标准差、血小板压积、白蛋白、系统性免疫-炎症指数及C反应蛋白/白蛋白是川崎病患儿丙种球蛋白耐药的预测因素。基于上述预测因素构建Nomogram模型,并分别在训练集与验证集人群中进行验证。训练集ROC曲线下面积(AUC)为0.784(95%CI:0.701,0.867),当最佳阈值取0.045时,相应的特异性和敏感性分别为0.490(95%CI:0.434,0.546)和0.935(95%CI:0.849,1.000);验证... 相似文献
82.
目的 探讨影响卵巢早衰的危险因素及保护因素,为卵巢早衰的预防提供科学依据.方法 选取确诊的卵巢早衰(premature ovarian failure,POF)女性60例为研究组,同时选取月经规则、性激素检查在正常范围内的、年龄匹配的卵巢功能正常的女性60名为对照组,分别填写自制《POF相关因素调查问卷表》,对调查结果进行比较,并采用单因素、多因素Logistic回归法进行分析.结果 POF的危险因素有盆腔手术史、腮腺炎史、染发、小事烦恼、疲倦、压抑及压力大;保护因素为经常食用水果蔬菜与豆制品.结论 养成良好的生活习惯,多食水果蔬菜及豆制品,不染发,远离有毒物质,及时预防接种,学会调整及缓解压力,减少负面情绪,保持心理健康有利于维持正常的卵巢功能. 相似文献
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Summary Serum-insulin levels were measured in 1770 subjects one hour after a 50 g glucose load. Multiple regression analyses reveal that a substantial proportion of the variability of log10 serum-insulin can be attributed to significant independent effect of blood-sugar, age, the food-interval, sex, parameters of body size, and scserum uric acid. Females have significantly higher levels of serum-insulin than males One-hour blood-sugar levels exceeding 160 nag/100 ml are associated with declining insulin levels. An independent association of increasing age with increasing serum-insulin is evident at 50 years and over. The findings provide strong support for the biological significance of serum-immunoreactive insulin.
Einfluß verschiedener Faktoren auf die Seruminsulinausschüttung bei einer Reihenuntersuchung
Zusammenfassung Die Seruminsulinspiegel 1 Std nach oraler Verabreichung von 50 g Glucose wurden bei 1770 Probanden bestimmt. Eine multiple Regressionsanalyse der Zehnerlogarithmuswerte für die Seruminsulinkonzentrationen ergab, daß ein beträchtlicher Teil der Variationsbreite durch signifikante und von einander unabhängige Einflüsse des Blutzuckers, des Alters, der Intervalle zwischen den Mahlzeiten, des Geschlechtes, des Körpergewichtes und der Harnsäure bedingt ist. Frauen wiesen significant höhere Insulinwerte als Männer auf. Häufig waren 1 Std Blutzuckerwerte über 160 mg% mit sinkenden Insulinspiegeln gekoppelt. Bei über 50 jährigen stiegen mit zunehmendem Alter auch die Insulinwerte an. Die Befunde stützen die Annahme, daß den immunologisch gemessenen Seruminsulinspiegeln biologische Bedeutung zukommt.
Facteurs déterminant la réponse de Vinsuline sérique dans un échantillon de population
Résumé Les taux d'insuline sérique ont été mesurés chez 1770 sujets une heure après une charge en glucose de 50 g. Des analyses de régression multiple révèlent qu'une proportion considérable de la variabilité du log10 de l'insuline sérique revient de façon significative aux effets indépendants entre eux de la glycémie, de l'âge, de l'intervalle entre les repas, du sexe, des paramètres de la taille corporelle et de l'acide urique sérique. Les femmes ont des niveaux d'insuline sérique significativement plus élevés que les hommes. Les taux de la glycémie une heure après, dépassant 160 mg/100 ml sont associés à une défaillance des taux d'insuline. Une association indépendante entre l'augmentation de l'âge et l'augmentation de l'insuline sérique est évidente à 50 ans et plus. Ces résultats apportent un argument solide pour l'importance biologique de l'insuline immunoréactive du sérum.相似文献
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BackgroundWhether an individual is over 8 years old is of great significance in clinical medicine and law. The Demirjian, Willems and Cameriere methods are one of the most widely used methods of dental age estimation, but neither method was suitable in Eastern China. And all of them are time-consuming for clinical work. A new and time-saving method for judging whether an individual is 8 years old is yet to be proposed on Eastern Chinese population.AimThe paper proposes a method for judging whether an individual is 8 years old based on the relationship between age and the first premolar maturity index (I1PM), which is related to the measurement of the open apices of the first premolar.Subjects & MethodsIt is a retrospective study where orthopantomograms of 748 children (356 female and 392male) aged 5–13 years were collected and analyzed. Linear regression was used to infer the value of I1PM for eastern China. Furthermore, this method was compared to those based on Demirjian’s stages F.Results and ConclusionsA cutoff value of I1PM = 0.35 was taken. The sensitivity of this test was 90.0% and specificity was 93.3%. Furthermore, the proportion of individuals with a correct classification was 90.9%. The results of the test showed that Demirjian’s stage F performance was lightly better than I1pm < 0.35. However, the sensitivity, specificity, and overall accuracy of both are greater than or equal to 90.0%, and the differences are not very significant. 相似文献
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Hongzhi Wang Emily W. Baker Abhyuday Mandal Ramana M. Pidaparti Franklin D. West Holly A. Kinder 《中国神经再生研究》2021,16(2):338
Traumatic brain injury(TBI) at a young age can lead to the development of long-term functional impairments. Severity of injury is well demonstrated to have a strong influence on the extent of functional impairments; however, identification of specific magnetic resonance imaging(MRI) biomarkers that are most reflective of injury severity and functional prognosis remain elusive. Therefore, the objective of this study was to utilize advanced statistical approaches to identify clinically relevant MRI biomarkers and predict functional outcomes using MRI metrics in a translational large animal piglet TBI model. TBI was induced via controlled cortical impact and multiparametric MRI was performed at 24 hours and 12 weeks post-TBI using T1-weighted, T2-weighted, T2-weighted fluid attenuated inversion recovery, diffusion-weighted imaging, and diffusion tensor imaging. Changes in spatiotemporal gait parameters were also assessed using an automated gait mat at 24 hours and 12 weeks post-TBI. Principal component analysis was performed to determine the MRI metrics and spatiotemporal gait parameters that explain the largest sources of variation within the datasets. We found that linear combinations of lesion size and midline shift acquired using T2-weighted imaging explained most of the variability of the data at both 24 hours and 12 weeks post-TBI. In addition, linear combinations of velocity, cadence, and stride length were found to explain most of the gait data variability at 24 hours and 12 weeks post-TBI. Linear regression analysis was performed to determine if MRI metrics are predictive of changes in gait. We found that both lesion size and midline shift are significantly correlated with decreases in stride and step length. These results from this study provide an important first step at identifying relevant MRI and functional biomarkers that are predictive of functional outcomes in a clinically relevant piglet TBI model. This study was approved by the University of Georgia Institutional Animal Care and Use Committee(AUP: A2015 11-001) on December 22, 2015. 相似文献
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The annual statistical survey conducted at the end of 2000 by the Japanese Society for Dialysis Therapy collected responses from 3358 (99.94%) of 3360 institutions. Japan's total dialysis patient population at the end of the year 2000, as identified by this survey, was 206,134, an increase of 8921 (4.5%) over 1999. This translates to 1624.1 patients per million population. The annual crude mortality rate was 9.4% for the period starting at the end of the year 1999 and ending at the end of the year 2000. The mean patient age at the initiation of dialysis treatment was 63.8 (+/- 13.9; +/- SD) years; the mean age of the overall dialysis patient population was 61.2 years (+/- 13.3). Both these mean ages, which had been increasing since 1983, again continued to increase. Among the primary diagnosis, the prevalence of diabetic nephropathy had continued to increase again since 1999, to 36.6%, whereas that of chronic glomerulonephritis had continued to decline, down to 32.5%, during the same one-year period since the 1999 survey. The 2000 years-end survey incorporated the following additional variables for the first time: usage of oral antihypertensives, pre- and post-dialysis systolic and diastolic blood pressures, serum HDL cholesterol level, types and dosage of oral Vitamin D analogs administered, dosage of oral calcium carbonate administered, history of intervention for peripheral vascular disease (bypass surgery, synthetic graft replacement, stenting), history of coronary artery bypass grafting (CABG), history of percutaneous transluminal coronary angioplasty (PTCA), whether stenting had been previously performed for the treatment of ischemic heart disease, number of cigarettes smoked, the type of vascular access used at the initiation of dialysis, and the year and month the vascular access was created. The survey results indicate that 60.9% of the total dialysis patient population was using oral antihypertensives. The patients' mean serum HDL cholesterol level was 47.65 +/- 18.47 mg/dL, showing positive correlation with serum albumin level and reverse correlation with body mass index. 1.6% of all dialysis patients had previously undergone amputation, and 0.7% had a history of bypass surgery for peripheral vascular disorder. 4.5% of hemodialysis patients had a history of cardiac infarction, 1.6% had previously undergone CABG, and 2.8%, PTCA. At the time the survey was conducted, 2.0% of all dialysis patients were undergoing oral Vitamin D analog pulse therapy, and 6% were undergoing intravenous Vitamin D analog pulse therapy. A history of amputation, myocardial infarction, cerebral infarction, and cerebral bleeding were identified as high-risk factors of vital prognosis. Additionally, high mortality risk was associated with the following: glutamic-pyruvic transaminase levels exceeding 20 IU/L; positive HCV antibody status; comorbid conditions such as hepatic cell carcinoma and liver cirrhosis; platelet counts below 100,000/mL or equal to or greater than 200,000/mL; C-reactive protein levels of 0.2 mg/dL and higher, leukocyte counts of less than 3000/mL or equal to or greater than 8000/mL; and body mass index of below 22 kg/m2, as well as total serum cholesterol levels of below 160 mg/dL or equal to or greater than 260 mg/dL. 相似文献