Impact of Correlated Factors on Bone Density in Individuals with a Family History of Osteoporosis

Previous studies have suggested that 14-47% of the variation in bone mineral density (BMD) can be predicted using clinical risk factors. The aim of our study was to determine, for the first time, the importance of these factors in individuals with evidence of a genetic predisposition to the disease. The subjects studied were 147 female and 86 male Caucasians, all with a family history of osteoporosis. Linear regression was used to determine whether age, height, weight, and years of reduced estrogen exposure were significant predictors of BMD. Males and females were examined separately, and BMD was measured at the hip and spine. The results show that these risk factors, known to be at work in the general population, are equally important in those with a family history of osteoporosis. It is clear, therefore, that they must be taken into account, and corrected for in genetic studies of the disease.     

回归的正交设计

本文借助于线性变换及正交表的特性,提供一个解线性回归方程的简便方法。这个方法适用于任意位级和混合位级的等距多因素正交试验。     

Cryoinsult parameter effects on the histologically apparent volume of experimentally induced osteonecrotic lesions

Investigation of femoral head osteonecrosis would benefit from an animal model whose natural history includes progression to bony collapse of a segmental necrotic lesion. The bipedal emu holds attraction for systematic organ‐level study of collapse mechanopathology. One established method of experimentally inducing segmental lesions is liquid nitrogen cryoinsult. Four cryoinsult parameters—hold temperature, freeze duration, freeze/thaw repetition, and thaw duration—were investigated to determine their individual and combined effects on resulting necrotic lesion morphology. 3D distributions of histologically apparent osteocyte necrosis from 24 emus receiving varying cryoinsults were used to develop univariate and multivariate linear regression models relating resulting necrotic lesion morphology to particular cryoinsult input parameters. These models were then applied to predict lesion size in four additional emus receiving differing input cryoinsults. The best multivariate regression model predicted lesion volumes that were accurate to better than 8% of overall emu femoral head volume. The hold temperature during cryoinsult was by far the most influential cryoinsult input parameter. The utility of this information is to enhance the consistency and predictability of cryoinsult‐induced segmental lesion size for the purposes of systematic laboratory studies at the whole‐organ level. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:931–937     

Pharmacokinetic studies of cyclosporine in Oriental kidney transplantation patients

SUMMARY: Pharmacokinetic studies were performed in 10 stable kidney transplantation patients who received microemulsion formulation (Neoral^®) of cyclosporine A (CsA) twice daily. No agents having pharmacokinetic effects on CsA had been used in these patients. The values of various basic pharmacokinetic parameters were similar to those reported in Western literature. The complete area under the blood concentration–time curve (AUC) of CsA for the duration of 12 h (12‐h AUC) was determined using the linear trapezoidal rule from seven concentrations at 0, 1, 2, 4, 6, 8, and 12 h after CsA administration. The mean values of 12‐h AUC were 4603.63 ± 344.61 ng h/mL. CsA concentrations at 2 h after dosing (not the trough levels) showed the best correlation with the complete AUC (r² = 0.9322). The abbreviated AUC of CsA was calculated either by stepwise multiple linear regression analysis or by the linear trapezoidal rule from a few sampling time points. Using stepwise multiple linear regression analysis, which was used in calculating abbreviated AUC in all previous studies, the model equation that had the highest correlation and the lowest prediction error with the complete AUC was derived by using CsA concentrations at 2 and 8 h after dosing (12‐h AUC = 4.262C₂ + 8.390C₈? 669.417; r² = 0.9808, absolute prediction error = 3.97 ± 0.96). Two model equations derived using the linear trapezoidal rule provided the best correlation with the complete AUC: (1) The two time points selected model equation 12‐h AUC = 4C₂ + 5C₈; r² = 0.9780, absolute prediction error = 6.41 ± 1.22). (2) The three time points selected model equation 12‐h AUC = 4C₀ + 3C₂ + 5C₆; r² = 0.9475, absolute prediction error = 5.00 ± 1.41). When different pharmacokinetic data sets were applied to the model equations derived using regression analysis, the values of coefficients and the constant of the regression equation had changed from the initial equation. Thus, new model equations will emerge every time the new data are applied. In contrast, the values of coefficients in the model equation calculated using trapezoidal rule were unaltered when tested by the new pharmacokinetic data set. Thus, the abbreviated AUC derived using the linear trapezoidal rule would be simpler than and superior to that obtained using stepwise multiple linear regression analysis in prediction of the complete AUC.     

多元线性回归法分析PSA的影响因素

目的:用多元线性回归的方法分析各个影响因素对于PSA的影响大小。方法:对6个自变量X1年龄、X2前列腺体积、X3剩余尿多少、X4血胆固醇、X5泌尿系感染程度、X6影像学占位赋值后,用多元线性回归的方法计算自变量对应变量Y:TPSA的偏回归系数。结果:泌尿系感染、前列腺大小、年龄与PSA之间存在线性关系,影响大小依次为泌尿系感染前列腺大小年龄,其中泌尿系感染、前列腺体积对于PSA为正影响,年龄则为负影响。剩余尿多少及患者是否有尿潴留对于F/T比值有着正影响。结论:泌尿系感染加重、前列腺体积增大一定程度可以增大PSA,年龄增加可以减小PSA。剩余尿增加及患者发生尿潴留可以增大F/T比值。     

上海市婚后六年妻子避孕知识状况及影响因素分析

目的 :了解上海市 80年代末初婚 76 93对夫妇婚后 6年内妻子避孕知识状况。方法 :由描述及拟合多元线性回归模型对影响妻子婚后 6年时避孕知识得分的因素进行分析。结果 :该时 96 .3 %的夫妇已有一孩 ;妻子平均避孕知识得分 ( 1 6 .4分 )虽明显高于新婚 3个月时 ( 5.9分 ) ,但与婚后 1 5个月时比较 ( 1 1 .9分 ) ,无显著差异 ;0 .9%仍对避孕措施一无所知 ;2 0 .5%仍不会正确使用避孕套 ;虽 95%知道口服药 ,仅 3 1 .8%能正确述出使用方法 ,对安全期基本了解的正确性相对较高 ,在 91 .7%的知道该措施的妻子中 ,77.1 %能基本掌握推算排卵期方法。多元回归模型显示 ,该时妻子避孕知识得分主要与其对避孕措施的负性态度、了解生殖健康有关知识的广度或受丈夫的避孕知识的影响有明显关系。不了解避孕套能预防艾滋病、性病或不愿使用某避孕措施的妻子其避孕知识得分明显偏低 ;产后首选非宫内节育器或有多种性生活体位者该时的避孕知识得分也相对较高。结论 :随婚后时间的推移 ,上海市妻子避孕知识增长趋向缓慢。计划生育工作人员及社会媒体有必要结合生殖健康知识的普及 ,继续加强对已生育孩子的夫妇双方避孕知识 ,特别是口服药对妇女健康效应的教育 ,以提高可接受性 ,进一步保障妇女健康、降低人工流产率。     

中老年妇女腰椎骨密度变化的多因素分析

目的 探讨影响中老年妇女腰椎骨密度的主要生理因素.方法 对198例中老年妇女的腰椎(一)的骨密度(BMD)进行检测,同时将检测结果 与年龄、身高、体重、绝经年龄分别进行相关分析和线性回归分析.结果 腰椎骨密度与年龄呈负相关(P＜0.001),与绝经年龄呈负相关(P＜0.001);与身高呈正相关(P＜0.05),与体重呈...     

以CUSUM方法分析达芬奇机器人肺叶切除术的学习曲线

目的探讨109例达芬奇机器人肺叶切除术的学习曲线。 方法以累积和分析法(cumulative sum analysis,CUSUM)分析沈阳军区总医院2012年3月至2015年2月完成的第1例至第109例达芬奇机器人肺叶切除术的手术时间。采用多元线性回归排除影响手术时间的因素。对CUSUM学习曲线进行拟合,以R²判断拟合优度。比较学习曲线不同阶段的手术时间、术中出血量、淋巴结清扫、术后并发症、术后带管时间和住院时间的差异。 结果手术时间随手术例数的累积呈逐渐下降趋势。学习曲线最佳拟合为三次方曲线,拟合优度系数R²＝0.847,拟合方程：CUSUM(n)＝0.002× n³－0.323 × n² ＋ 13.360 × n － 18.195(n为手术例数)。拟合曲线在手术例数累积至第28例时达到顶点,以此为分界将学习曲线划分为两个阶段,其手术时间(P＝0.022)、术中出血量(P＝0.014)、清扫淋巴结数目(P＝0.022)、术后并发症(P＝0.015)、术后带管时间(P＝0.025)和住院时间(P＝0.005)均存在显著的统计学差异。 结论通过CUSUM分析法对达芬奇机器人肺叶切除术的学习曲线进行精确分析,表明掌握该技术须累积的手术例数为28例。     

国人全膝置换术后评分系统与患者实际满意度一致性分析

目的人工全膝关节置换在国内已广泛开展,评价置换效果的评分系统主要采用KSS、WOMAC和SF-36等系统。这些系统关注的焦点与中国患者关注的焦点是否一致,评分细则是否符合中国国情,一直没有得到有效的评价,本文旨在比较并评价以上系统。方法采用直线相关回归的方法,评价204例患者的KSS、WOMAC、SF-36评分和患者主观满意度之间的相关性,从而评价上述评分对中国患者的适用度。结果 KSS评分和WOMAC评分值与患者的主观满意度相关性较差,决定系数低于0.6。SF-36评分在术后1周时与患者满意度高度相关,在术后3个月时不相关。结论国人对膝关节功能的要求更多的在于屈膝下蹲等动作,对疼痛的耐受较好,类似因素影响了KSS和WOMAC评分与患者主观满意度的一致性。上述评分应针对国人关注焦点改变权重,以便更好的用于膝关节置换手术的评价。     

New multifactorial burn resuscitation formula offers superior predictive reliability in comparison to established algorithms

The Parkland–Baxter formula is a widely utilized resuscitation guideline for the initial management of fluid deficits in burn victims. Implementation of resuscitation formulas has helped to reduce the incidence of shock and hypovolemic organ failure such as acute renal failure in the setting of burn trauma. However, it has been shown that indiscriminate implementation of these formulas may inappropriately suit individual patient’s requirements. In our experience resuscitation by the Parkland formula often forced corrections in order to reach predefined resuscitation goals.     

Host response to xenograft ECM implantation is not different between the shoulder and body wall sites in the rat model

In the context of tendon and ligament repair, mechanical loading and the presence of joint synovial fluid are known to profoundly influence the form and function of the repair tissue and potentially the host response to biomaterials. Previously, we demonstrated that a xenograft extra cellular matrix (ECM) scaffold implanted in the rat shoulder elicited a unique host response from that seen in the body wall. However, the host response to xenografts implanted in shoulders with a tendon/capsule injury was not different from xenografts implanted in shoulders with no injury. In the current study, we hypothesized that varying clinically relevant surgical and environmental factors would introduce significant differences in host response to xenograft implantation at the shoulder. Contrary to our hypothesis, we found no significant differences in host response between any shoulder implantation conditions or between shoulder and body wall implantation in the rat model. These findings suggest that there is no advantage to using an orthotopic shoulder model to investigate the host response to rotator cuff scaffold materials in the rat model, and due to the insensitivity of its host response to various clinically relevant surgical conditions, may suggest that the rat does not provide a surrogate for directly translating the host response to biomaterials to the human application. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1725–1731, 2012     

急诊神经外科手术患者术中血乳酸影响因素的回顾性分析

目的研究麻醉手术过程中常见监测指标对血乳酸(Lac)的影响。方法选择我院2016年4月至2019年5月急诊神经外科手术患者103例,男59例,女44例,年龄18～87岁,BMI 18～35 kg/m~2,ASAⅢ或Ⅴ级,采集麦迪斯顿手术麻醉信息系统麻醉记录单中患者一般资料及术中血气分析结果,记录患者术中Lac、Hb、血糖(Glu)、MAP、HR、休克指数(SI),以Lac为应变量,其他指标作为自变量,通过多重线性回归分析方法分析其线性关系,并通过逐步回归分析方法筛选较理想的多重线性回归方程,筛选对Lac有统计学意义的自变量。结果 Lac与Hb、Glu和SI存在正相关关系,Lac与各自变量之间多重线性回归方程有统计学意义(r~2=0.427,P=0.003)。通过逐步回归分析后得到仅有Hb(P0.001)、Glu(P0.05)和SI(P=0.018)的回归模型。结论急诊神经外科患者术中Lac与Hb、Glu及SI存在一定的线性关系,术中做好上述指标管理有利于减少患者高乳酸血症的发生,实现对患者的精细化管理。     

Truncated $L_1$ Regularized Linear Regression: Theory and Algorithm

Truncated $L_1$ regularization proposed by Fan in [5], is an approximation to the $L_0$ regularization in high-dimensional sparse models. In this work, we prove the non-asymptotic error bound for the global optimal solution to the truncated $L_1$ regularized linear regression problem and study the support recovery property. Moreover, a primal dual active set algorithm (PDAS) for variable estimation and selection is proposed. Coupled with continuation by a warm-start strategy leads to a primal dual active set with continuation algorithm (PDASC). Data-driven parameter selection rules such as cross validation, BIC or voting method can be applied to select a proper regularization parameter. The application of the proposed method is demonstrated by applying it to simulation data and a breast cancer gene expression data set (bcTCGA).     

髌股疼痛综合征X线特征与三种评分系统的多元线性回归分析

目的采用X线测量发生髌股疼痛综合征(PFPS)膝关节的相关影像学参数,并分别与WOMAC、KUJALA和MELBOURNE评分系统进行多元线性回归分析。方法筛选出49例(51膝)膝关节选取和PFPS相关的10项参数进行测量:股骨远端外翻角(DFVA,X1)、胫骨近端内翻角(PTVA,X2)、股骨角(FA,X3)、胫骨角(TA,X4)、胫股角(TFA,X5)、Insall-Salvati指数(ISR,X6)、沟角(SA,X7)、外侧髌骨角(LPA,X8)、适合角(CA,X9)、髌股指数(PI,X10),并进行WOMAC、KUJALA和MELBOURNE评分,应用多元线性回归方程分析影像学参数与评分之间的相关性。结果 3组多元线性回归方程均有统计学意义(P<0.05),WOMAC评分多元回归方程:Y=-213.742+2.011X5,F=3.960,R2=0.494;KUJALA评分多元回归方程:Y=125.835-24.475X6-0.341X7-0.992X8,F=32.732,R2=0.891;MELBOURNE评分多元回归方程:Y=51.66-16.329X6-5.47X10,F=22.178,R2=0.856。结论①膝关节X线测量数据在一定程度上反映3项评分及膝关节功能的情况;②KUJALA评分能较全面地评估PFPS,轴位X线片上Insall-Salvati指数、沟角、外侧髌股角较为重要,可用于临床评估PFPS患者在治疗前后的功能恢复情况;③由于KUJALA和MELBOURNE评分的决定系数较大,回归系数标准误较小,从而在临床上通过统计控制确定评分值来评估影像学参数。     

胸腰椎骨折前路手术中冠状面Cobb角变化规律及其影响因素的多元线性回归分析

[目的]探讨胸腰椎骨折前路手术过程中脊柱冠状面Cobb角的变化规律,通过多元线性回归分析寻找导致术后侧方成角的可能影响因素.[方法]前瞻性连续性研究2008年6月～2009年3月经前路手术治疗的60例胸腰椎爆裂性骨折,测量每一位患者的术前、腰桥前、腰桥后(16例使用了腰桥)、撑开器后、切椎间盘后、加压后、术后前后位X线冠状面Cobb角,并测量术后前后位X线片上椎体螺钉与相应终板的夹角.根据解剖特点分为全部病例组、胸椎组、腰椎组、L1组、L2/3组;根据是否使用腰桥分为腰桥组、无腰桥组.分析各组在手术的不同阶段冠状面Cobb角变化规律.应用重复数据设计资料的方差分析进行组间比较.并对术后冠状面Cobb角的影响因素进行多元线性回归关系分析.[结果]全部病例组、腰椎组、L1组、L2/3组、无腰桥组、有腰桥组6个组中均存在摆体位时脊柱向对侧轻度侧方成角,撑开器撑开后,切椎间盘后及有腰桥组的腰桥后脊柱出现明显向同侧侧方成角,应用撑开器撑开后脊柱向同侧侧方成角明显加大,使用腰桥后加重此趋势.胸椎组在前4个节段变化小,仅在加压安棒后出现脊柱向对侧侧方成角的现象.重复数据测量两两比较显示胸椎组与腰椎组以及胸椎组与L1组的变化趋势差异有统计学意义.多元线性回归分析显示影响术后冠状面Cobb角的主要因素是椎体螺钉A+D角或B+C角.[结论]除胸椎组外应用腰桥和撑开器撑开后导致了明显的脊柱侧方成角,此可能会诱导术中安置椎体螺钉的方向出错.对术后冠状面Cobb角的最大影响因素是椎体螺钉的进钉方向.     

微型钢板治疗粉碎性掌指骨骨折术后手指功能影响因素多元线性回归分析

目的分析影响微型钢板内固定治疗粉碎性关节周围掌指骨骨折术后手指功能的影响因素。方法采用前瞻性队列研究方法,对120例粉碎性关节周围掌指骨骨折的患者行微型钢板内固定术,测定术后手指关节总主动活动度(TAM),与对侧比较计算%TAM。将之与8个影响因素作比较,包括年龄、性别、优势手、骨折部位、钢板位置、伤后手术时间、是否关节内骨折及是否伴随软组织损伤。采用线性相关分析单变量之间的关系,确定线性相关因素后采用多元线性回归分析研究各影响因素与术后%TAM的关系。结果线性相关分析显示骨折部位、是否合并软组织损伤和年龄与术后%TAM有明显相关性(P0.001)。包括这3个因素的多元线性回归模型的结果说明其与术后%TAM有明显相关性:骨折部位(β=-0.375,P0.001),是否合并软组织损伤(β=-0.335,P0.001),年龄(β=-0.238,P0.001)。结论微型钢板治疗粉碎性关节周围掌指骨骨折术后手指功能%TAM与骨折部位、是否合并软组织损伤及年龄密切相关,指骨骨折、合并软组织损伤及高龄可明显影响术后手部功能恢复。