基于Adaptive-Lasso Logistics模型的方剂学学习动机影响因素分析

目的讨论Adaptive lasso-logistic回归模型在方剂学学习动机的影响因素中的应用。方法基于成都市某大学在校2017级学生进行分层抽样,综合运用方差分析及lasso-logistic回归模型,利用R软件分析学生在方剂学学习过程中关于学习动机的影响因素。结果模型共纳入662名学生,通过交叉验证法,可知Adaptive lasso-logistic回归模型中纳入的变量为:外驱动机、学习信念、考试焦虑、性别、专业、科别。从时间成本和模型简洁度来看,Adaptive-lasso logistic模型优于全变量logistic模型和ridge logistic模型。结论Adaptive-Lasso Logistics回归模型在压缩模型、变量筛选以及预测准确率上更有效,有助于了解学生的学习动机,为教学工作者后续教学安排提供一定的参考意见。     

奇异变形菌中整合子分布及耐药性分析

目的 了解院内奇异变形菌中各类整合子的携带分布情况、阳性菌株可变区基因盒类型以及其与宿主菌耐药表型的相关性,从而为临床治疗和院内感染控制提供参考。方法 采用PCR扩增和琼脂糖凝胶电泳等方法,将本院2016年1月—2018年12月份从临床标本中分离得到的150株奇异变形菌进行第1、2和3类整合子的筛选,并对整合子阳性菌株可变区进行测序分析以及宿主菌的耐药性进行相关性分析。结果 150株奇异变形菌中携带整合子的菌株共有91株,阳性率为60.7%,其中第1类整合子阳性菌株有30株,占20.0%;第2类整合子阳性菌株22株,占14.7%;同时携带第1和2类菌株39株,占26.0%;未筛出第3类整合子;在91株整合子阳性菌株中,86株可变区出现扩增产物条带,其余5株可变区未见扩增产物;第1类整合子阳性菌株可变区携带的耐药基因盒主要为AadA2、DfrA32,第2类整合子阳性菌株可变区携带耐药基因盒主要为DfrA1;可变区携带AadA2的菌株对庆大霉素和妥布霉素的耐药率显著高于整合子阴性菌株(P<0.01),可变区携带DfrA1或DfrA32的菌株对复方磺胺甲噁唑(即甲氧苄啶/磺胺甲噁唑)的耐药率也明显高于整合子阴性菌株(P<0.01);91株整合子阳性菌株对氨苄西林/舒巴坦、复方磺胺甲噁唑、环丙沙星、庆大霉素、头孢曲松、妥布霉素和左氧氟沙星的耐药率均显著高于整合子阴性菌株(P<0.01)。结论     

Trypanosoma brucei: Effect of inhibition of N-linked glycosylation on the nearest neighbor analysis of the major variable surface coat glycoprotein

As an assay for the surface deposition of newly synthesized major variable surface coat glycoprotein (VSCG) we have treated intact Trypanosoma brucei cells with the cleavable cross-linking reagent dithiobis-(succinimidyl propionate). Under appropriate conditions, surface VSCG is converted to oligomers of n not less than 8. The oligomeric protein, apparent molecular weight greater than 4 × 10⁵, does not migrate more than 1 to 2 mm into a 3–15% linear polyacrylamide gradient gel containing 0.1% sodium dodecyl sulfate, hence the appearance of newly synthesized radiolabeled protein in the top 2 mm of the gel indicates the translocation of VSCG from the site of synthesis to the surface and the gross establishment of normal interactions among the molecules. In addition, purified VSCG treated with the cross-linking reagent yielded a dimeric product on gel electrophoresis. To examine the role of N-linked carbohydrate in the translocation of the protein and in intermolecular interactions we have allowed trypanosomes to incorporate L-[¹⁴C]serine into protein in the presence of the antibiotic tunicamycin. Our results show that N-linked carbohydrate is not essential to the transfer of VSCG to the cell surface nor does its absence interfere with gross intermolecular interactions in the short term. On the other hand N-linked carbohydrate does appear to play an essential role in dimer formation.     

IS6110-RFLP、Spoligotyping和MLVA在结核分枝杆菌基因分型中的应用研究

目的 评价156110限制性片段长度多态性（IS6110-RFLP）、间隔区寡核苷酸分型（Spoligotyping）及多位点可变数量串联重复序列分析（MLVA）3种方法在结核分枝杆菌基因分型研究中的应用。方法 分别采用IS6110-RFLP、Spoligotyping及MLVA对40株结核分枝杆菌临床分离株进行基因分型研究，比较3种方法的分型效果。结果 使用IS6110-RFLP方法，40株结核分枝杆菌呈现出35种基因型，33株具有独特的基因型；使用Spoligotyping方法，40株结核分枝杆菌呈现出17种基因型，11株具有独特的基因型；使用MLVA方法时，40株结核分枝杆菌呈现出34种基因型，29株具有独特的基因型；当3种方法联合使用时，40株结核分枝杆菌呈现出39种基因型，38株具有独特的基因型。结论 MLVA和IS6110-RFLP方法的分辨率高于Spoligotyping，但是对于IS6110单拷贝或低拷贝的菌株，MLVA方法的分辨率要高于IS6110-RFLP。MLVA、IS6110-RFLP和Spoligotyping联合应用可有效地进行结核病的流行病学调查和病原学监测。     

提高回归模型拟合优度的策略(Ⅱ)——算术均值变换与其他变量变换

本文目的是介绍第二种提高回归模型拟合优度的策略,即算术均值变换与其他变量变换。具体方法包括以下几个方面:①对多值名义自变量采取"算术均值变换";②对定量自变量引入派生变量,包括"对数变换""平方根变换""指数变换""平方变换""立方变换"和"交叉乘积变换"的结果;③对定量因变量分别采取"对数变换""平方根变换""指数变换""倒数变换"和"Logistic变换";④构建回归模型时,在假定"包含截距项"与"不含截距项"的条件下,分别采取"前进法""后退法"和"逐步法"筛选自变量。得到了如下结论:①对定量因变量和自变量不做变量变换时,回归模型的拟合优度非常差;②根据资料所具备的条件,对定量因变量采取不同的变量变换方法,其回归模型的拟合优度是不同的;③对多值名义自变量进行"算术均值变换"是合理的,且有助于提高回归模型拟合优度;④对定量自变量引入派生变量是非常有价值的;⑤假定回归模型中不含截距项有助于提高回归模型的拟合优度。     

变量变换回归分析(Ⅰ)——拟合含间断点资料的方法

本文目的是介绍一种能很好地拟合具有间断点资料的方法。当资料中具有明确的间断点或整个资料包含多段不同变化趋势的曲线类型时,为了提高曲线回归模型对资料的拟合优度,需要充分发挥"节点"的作用。可基于两种不同视角来利用"节点":其一,人为设定不同数目的节点,利用样条变换方法拟合分段多项式曲线;其二,在客观存在的节点上,求曲线的一阶乃至四阶导数,并据此构建曲线回归模型。得到的结论是:后者的拟合效果优于前者。     

基于变异系数赋权与功效系数的医院综合评价

目的 为了解湛江市二级综合医院的医疗质量状况,对9家医院综合水平进行排序,找出某院与同行的差距,以及需要改进之处,为该院的发展提供决策依据.方法 从国家卫生统计信息网络直报系统提取2009年湛江市九家二级医院的直报数据,根据广东省卫生厅采用的指标公式整理并提取病床使用率、病床周转次数、平均住院日、病床工作日、有效率、病死率、住院危重病人抢救成功率、急诊抢救成功率、三日确诊率、入出诊断符合率、药品比例、平均每医生收治住院病人数、平均每医生负担诊疗人次、平均每诊疗人次医疗费、出院者平均每天住院医疗费等15个有代表性的医疗质量、效率指标.使用变异系数赋权与功效系数法,对这九家医院的上述指标进行综合评价.首先运用Excel求出标准差及变异系数,根据指标包含的信息确定权重,再计算功效系数,然后采用加权几何平均法计算出总功效系数,对结果进行排序.结果 A～I代表的九家医院医疗质量总功效系数分别为68.7、79.1、71.9、86.5、86.0、79.5、87.6、83.3、90.3.I单位平均住院日等4个指标排名第1,2个指标排第2,综合水平名列前茅;G单位病死率等3个指标排第1,平均住院日排第2,3个指标排第3,综合水平第2;A单位虽然出院者平均每天住院医疗费排第1,有效率排第2,但是病床使用率等权重较大的8个指标排在第8或9,综合水平排名最后.结论 A单位在医疗技术培训、抢救水平、外科及儿科建设、宣传等方面要加大力度,提升医疗质量.     

DNA methylation as a risk factor in the effects of early life stress

Epigenetic marks (e.g., DNA 5-methylcytosine [5mC] content or CpG methylation) within specific gene regulatory regions have been demonstrated to play diverse roles in stress adaptation and resulting health trajectories following early adversity. Yet the developmental programming of the vast majority of the epigenome has not yet been characterized, and its role in the impact of early stress largely unknown. In the present study, we investigated the relationships among early life stress, whole-epigenome and candidate stress pathway gene (serotonin transporter, 5-HTT) methylation patterns, and adult behavioral stress adaptation in a non-human primate model. Early in life, experimental variable foraging demand (VFD) stress or control conditions were administered to two groups each of 10 female bonnet macaques (Macaca radiata) and their mothers. As adults (3–13 years of age), these females were assessed for behavioral adaptation to stress across four conditions of increasing intensity. Blood DNA 5-HTT 5mC status was determined using sodium bisulfite pyrosequencing and total 5mC content was determined using ELISA. Neither stress reactivity nor DNA methylation differed based on early life stress. However, we found that both greater 5-HTT and whole-genome 5mC was associated with enhanced behavioral stress reactivity following early life stress, but not control conditions. Therefore, regardless of developmental origin, greater DNA methylation conferred a genomic background of “risk” in the context of early stress. We suggest that this may arise from constrained plasticity in gene expression needed for stress adaptation early in development. This risk may have wider implications for psychological and physical stress adaptation and health.     

Association between the dopamine transporter gene and the inattentive subtype of attention deficit hyperactivity disorder in Taiwan

Attention deficit hyperactivity disorder (ADHD) is a common heritable childhood psychiatric disorder. Since methylphenidate, one of the main drugs used to treat ADHD, targets the dopamine transporter, this study examined the linkage disequilibrium (LD) structure of the dopamine transporter gene (DAT1) and investigated whether the DAT1 gene was associated with ADHD. This Chinese family-based association sample consisted of 273 DSM-IV diagnosed ADHD probands and their family members (n = 906). We screened 15 polymorphisms across the DAT1 gene, including 14 single nucleotide polymorphism (SNP) markers and the variable number of tandem repeat (VNTR) polymorphism in 3′-untranslated region (3′UTR). Calculations of pairwise LD revealed three main haplotype blocks (HBs): HB1 (intron 2 through intron 6), HB2 (intron 8 through intron 11), and HB3 (3′UTR). Family-Based Association Tests showed that no allele was significantly more transmitted than expected to the ADHD children for these 15 markers. Haplotype-Based Association Tests showed that a haplotype rs27048 (C)/rs429699 (T) was significantly associated with the inattentive subtype (P = 0.008). In quantitative analyses, this haplotype also demonstrated significant association with the inattention severity (P = 0.012). Our finding of the haplotype rs27048 (C)/rs429699 (T) as a novel genetic marker in the inattentive ADHD subtype suggests that variation in the DAT1 gene may primarily affect the inattentive subtype of ADHD.