Certain characteristics of myocardial contractility of isovolumic dog heart at randomly variable heart rhythm

Summary The relationship heart rate-left ventricular pressure was investigated in the isolated canine heart perfused with constant pressure at different preloads. Rhythmical stimulation was performed with constant stimulus interval duration and with stimulus intervals randomly changed near the average value (150–200 stimuli in series).Correlation and dispersion function analysis show that rhythm dispersion had a negative inotropic effect which was independent of the preload of the ventricle in the range of 120–180 beat/min, but this dependence occurred with low rates of stimulation.This method is proposed for the assessment of contractility under conditions of heart rate variations (physiological and pathological arrhythmias).     

鼠抗人纤维蛋白单链抗体-低相对分子质量单链尿激酶融合基因真核分泌表达载体的构建

目的 构建鼠抗人纤维蛋白单链抗体－低相对单链尿激酶融合基因真核分泌表达载体。方法 应用重组ＤＮＡ技 术,将人工合成的尿激酶原信号肽基因与鼠抗人纤维蛋白单链抗体－低相对分子质量单链尿激酶融合基因连接,并保 证在同一阅读框架,然后分别插科到pcＤＮＡ３和ＰＭＪＫ３两种真核表达载体中。结果构建成可以在真核细胞中分泌表 达鼠抗人纤维蛋白单链抗体－低相对分子质量单链尿激酶融合蛋白的重组质粒pcＤＮＡ３－Ｄ１和ｐＭＪＫ３－Ｄ１。结论为建 立稳定分泌表达鼠抗人纤维蛋白单链抗体－低相对分子质量单链尿激酶融合蛋白的细胞工程株奠定了基础。     

基于Group-Lasso天麻品质形成关键因子的分析

目的 为提高人工种植天麻的质量,基于Group-Lasso变量筛选构建随机森林回归模型分析影响天麻品质形成的关键因子。方法 基于Group-Lasso法,对2007—2022年天麻质量研究文献中天麻素含量及产地环境变量等数据进行变量筛选,并在筛选出的变量基础上建立随机森林回归模型及计算变量重要性得分。结果 最终选择了产区、生长状况、种质类型、产地气候类型、产地土壤类型、最热月均温、产地年降水量、产地年日照时数和无霜期9个变量,基于被选变量与天麻素含量建立随机森林回归模型,模型的均方误差（mean square error,MSE）和平均绝对百分误差（mean absolute percentage error,MAPE）分别为0.103 2和14.08%,特征重要性排序显示天麻素含量的最大影响因素是产地年降水量,其次是产地土壤类型、无霜期和产地年日照时数。结论 随机森林回归模型有相对较低的误差和较高的预估精度,更适合用于对天麻种植环境的分析和天麻素含量的估算,为人工种植天麻提供参考。     

焦化塔双线性建模及变结构控制

给出了基于综合优化方法的双线性系统建模和变结构控制设计方法,并将此用于延迟焦化装置,建立了焦化塔双线性模型和变结构控制器,转好地解决了抖振问题,仿真结果表明这一方法是有效的。     

Study on genetic polymorphisms of DCC gene VNTR in esophageal cancer

The abeted in Colo~ cancer gene (DCC) is re~ as a susceptibility gene in colol'eCtal cancer, whichis located on chlomesome 18qZI. 2. Ihactivation of thisgene may Play an i~ role dndng some Pimessessuch as ~ p~ssion and metastasis. With its ~allycloned, in lop, casinger et alllJ found that a vocablenumber tandem repeat (VNTR) is located wick an intwOf the DCC gene, its lepeat act is 2 hp,the core seqUence of (TA)n ~ numbers ~ 10 -- to tinies, whichis an ideal genetic rnalker. Esophageal…     

An Approach for Widening the Bioequivalence Acceptance Limits in the Case of Highly Variable Drugs

Purpose. Highly variable drugs pose a problem in bioequivalence assessment because they often fail to meet current regulatory acceptance criteria for average bioequivalence (80–125%). This paper examines alternative approaches to establishing bioequivalence. Methods. Suggested solutions have included alternate study designs, e.g., replicate and multiple dose studies, reducing the level of the confidence interval, and widening the acceptance limits. We focus on the latter approach. Results. A rationale is presented for defining wider acceptance limits for highly variable drugs. Two previously described methods are evaluated, and a new method having more desirable properties is proposed. Conclusions. We challenge the one size fits all current definition of bioequivalence acceptance limits for highly variable drugs, proposing alternative limits or goal posts which vary in accordance with the intrasubject variability of the reference product.     

sIL—4和细胞间粘附分子及总IgE在呼吸道炎症中的表达

目的探讨可溶性白细胞介素－4（solubleinterleukin－4,sIL－4）、细胞间粘附分子－1（in-tercellaradhesionmolecule－1,ICAM－1）在过敏性鼻炎（allergicrhinitis,AR）、咳嗽变异性哮喘（coughvariableasthma,CVA）、哮喘和慢性支气管炎发病中的作用。方法采用酶标法测定12例AR、21例CVA、29例哮喘缓解期、27例哮喘发作期、11例慢性支气管炎患者和10例正常健康人血标本。结果（1）sIL－4：CVA、哮喘发作期和慢支组高于正常组（P＜0．05）。AR、哮喘缓解期与正常组比较无显著性差异。（2）ICAM－1：各组均高于正常组（P＜0．05）。哮喘发作组又高于AR组和哮喘缓解组（P＜0．05）。（3）总IgE：除慢支组外其余各组均高于正常组（P＜0．05）。结论sIL－4、ICAM－1参与气道炎症的形成过程,且其含量的高低与咳嗽的发生呈平行发展关系。     

The involvement of an opiate mechanism in the sensitized behavioral deficit induced by early chronic variable stress: influence of desipramine

The influence of early chronic variable stress (CVS) associated with persistent desipramine (DMI) administration was examined on escape performance. Animals were exposed to CVS and 1 day later administered DMI (5 mg/kg, i.p. twice a day) or vehicle (VH) during six consecutive days. Escape performance was assessed over 24 h following inescapable shock (IS) exposure. Higher escape failures were observed in CVS shocked rats compared with unstressed shocked animals. DMI normalized escape failures in both groups. In order to investigate the role of an endogenous opiate mechanism presumably activated by CVS exposure in this behavioral deficit, rats were administered naltrexone (NAL, 2 mg/kg i.p.) or VH prior to each daily stressor of the CVS regime. NAL pretreatment blocked escape failures performed only by CVS shocked rats. In addition, animals were daily administered morphine (MOR, 10 mg/kg, i.p.) or VH during seven consecutive days and subsequently administered DMI. A significant increase in escape deficit in shocked rats was observed after chronic MOR but not following the associated treatment with MOR and DMI. These behavioral data suggest that early experience with a CVS facilitated the onset of escape deficit induced by a brief IS event, an effect that can be prevented by chronic DMI. Furthermore, this sensitized escape deficit response seems to be partially modulated by the previous activation of an opiate mechanism.     

Complexity of the immunoglobulin light chain V kappa 1 gene family in the New Zealand black mouse

The immunoglobulin light chain V kappa 1 gene family is polymorphic in murine inbred strains and this family has been subdivided into five sub-groups (V kappa 1A-E). The V kappa 1A sub-group contributes to approximately 2% of the total serum immunoglobulin light chains in several mouse strains. However, it has been reported that this sub-group is absent in New Zealand Black (NZB) mouse serum. Amino acid sequencing of myeloma proteins from this inbred mouse has shown that they belong to the V kappa 1B sub-group. We report here the structure of nine functional germline genes from NZB mice that have high homologies to the V kappa 1A, V kappa 1B, V kappa 1C, and V kappa 1D sub-groups. In addition, a novel germline gene representing the prototype of a new sub-group (designated V kappa 1F) has been identified. We have isolated different V kappa 1 germline genes from a single restriction fragment length polymorphism (RFLP) fragment, as well as identical V genes from two different RFLP migrating bands. Therefore, the complexity of the genes encoding the immunoglobulin variable region cannot be determined solely by RFLP analysis. Nucleotide sequence analysis of 16 V kappa 1 genes which code for NZB autoantibodies indicate that they belong to five different V kappa 1 sub-groups with five hybridomas (31%) expressing the V kappa 1A sub-group. Comparison of the sequences of V kappa 1 genes expressed in hybridomas with corresponding germline genes show no somatic mutations.