不同致伤条件撞击对兔钝性胸部创伤伤情影响的实验研究

探讨不同致伤参数对兔钝性胸部创伤后胸部筘器官伤情的影响。方法采用兔钝性胸部创伤型,设置不同的致伤参数,观察其对胸部各器 伤情影响及其对死亡率的影响。结果驱动压力越大,胸部各器官伤情越重;撞击面积越大,对胸壁和肺的损伤较重,但心脏伤情并不随之加重;收缩末期撞击对心脏的损伤较重,舒张末期撞击大血管系统的影响较大,死亡率与驱动压力、撞击面积成正;舒张末期撞击死亡率上升。结论致伤参数不同,对钝化胸部创伤后     

Determination of microviscosity and location of 1,3-Di(1-pyrenyl)propane in brain membranes

We determined the microviscosity of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex and liposomes of total lipids (SPMTL) and phospholipids (SPMPL) extracted from SPMV. Changes in the microviscosity induced by the range and rate of lateral diffusion were measured by the intramolecular excimerization of 1,3-di(1-pyrenyl)-propane (Py-3-Py). The microviscosity values of the direct probe environment in SPMV, SPMTL and SPMPL were 38.17, 31.11 and 27.64 cP, respectively, at 37°C and the activation energies (E_a) of the excimer formation of Py-3-Py in SPMV, SPMTL and SPMPL were 8.236, 7.448 amd 7.025 kcal/mol, respectively. Probe location was measured by polarity and polarizability parameters of the probe Py-3-Py and probe analogues, pyrene, 1-pyrenenonanol and 1-pyrenemethyl-3β-hydroxy-22,23-bisnor-5-cholenate (PMC), incorporated into membranes or solubilized in reference solvents. There existed a good linear relationship between the first absorption peak of the¹L_a band and the polarizability parameter (n ²−1)/(2n ²+1). The calculated refractive index values for SPMV, SPMTL and SPMPL were close to 1.50, which is higher than that of liquid paraffin (n=1.475). The probe location was also determined by using a polarity parameter (f−1/2f¹). Here f=(ε−1)/(2ε+1) is the dielectric constant function and f'=(n ²−1)/(2n ²+1) is the refractive index function. A correlation existed between the monomer fluorescence intensity ratio and the solvent polarity parameter. The probes incorporated in SPMV, SPMTL, and SPMPL report a polarity value close to that of 1-hexanol (ε=13.29). In conclusion, Py-3-Py is located completely inside the membrane, not in the very hydrophobic core, but displaced toward the polar head groups of phospholipid molecules, e.g., central methylene region of aliphatic chains of phospholipid molecules.     

Pharmacokinetics of methotrexate in leukemia cells: Effect of dose and mode of injection

A lumped compartmental model has been derived to predict methotrexate concentration as a function of time for L1210 cells in BD2F ₁ female mice at doses ranging from 3 mg/kg to 400 mg/kg. Using standard methods of parameter estimation as well as experimental determinations, an integrated approach was derived to account for the differences between the subcutaneous (s.c.) and intraperitoneal (i.p.) modes of injection. It was found that a single generalized forcing function can be used to fit plasma concentration after s.c. injection for all doses. Adequate fits (average error<20% while the standard deviation of experimental determinations was±22%) of L1210 cell data after s.c. injection were obtained. The best results were for a maximum facilitated influx constant V_max of 0.424 g/min/ml, a Michaelis influx constant K_m of 1,42 g/ml, and a first-order efflux constant of 0.047 min^–1.The model simulations were not sensitive to V_max, K_m,and so long as the ratio V_max/was approximately 9g/ml. The values of V _max ,K _m ,and which were obtained from our analysis of the in vivodata can be explained on the basis of previously performed in vitroexperiments. The parameters obtained from modeling the s.c. data were then applied for i.p. injection data. The resulting fits were adequate (average error<20% while the standard deviation of experimental determinations was±22%). A single generalized forcing function for drug concentration in the peritoneal cavity after i.p. injection for all doses was derived. The application of these results enables the prediction of methotrexate concentration in neoplastic cells at other doses after either s.c. or i.p. injection.     

Affected kin-pair IBD methods: genetic models.

Cases of interest using affected sib-pair methods to distinguish between recessive and additive (dominant) modes of inheritance of a disease-predisposing gene involve goodness-of-fit tests with a small expected number in the "share-zero parental haplotypes" category, as well as an unknown parameter, the frequency of the disease-predisposing allele. Our simulations demonstrate that the real significance level of the chi-square test using the three-haplotype-sharing IBD values (share 2, 1, and 0 parental haplotypes) is close to the assumed (.05) level in these cases, so that the haplotype-sharing classes do not have to be lumped, which would leave no degrees of freedom for a statistical test. The validity of the chi-square approximation in cases of small expected frequencies has previously been described, but the situations that have been considered do not cover the very small values in the share-zero category that are often expected in the affected sib-pair analysis, nor do they involve estimation of an unknown parameter. Although including IBD values from affected kin pairs other than sibs can be a very powerful tool in demonstrating linkage of a marker and disease, these pairs do not add power, in fact they reduce the power, of the chi-square tests of goodness-of-fit of modes of inheritance.     

The importance of employing stringent methods to recruit fertile male controls

Two methods of recruiting fertile male controls were evaluated and compared. The first group was recruited from the partners of women attending an antenatal clinic without obtaining details of their reproductive history. The second group was recruited after obtaining a detailed reproductive history from the couple and employing stringent entry criteria. Entry criteria for the second group included a length of exposure to the risk of pregnancy of not more than 12 months and no previous episode of involuntary infertility for either partner. There were significant differences between the distributions of semen parameters obtained from the two groups, indicating that the selection criteria for "fertile" men significantly influence results obtained and therefore that it is important to employ stringent criteria for the recruitment of fertile male controls. The group which was recruited by stringent criteria (mean length of exposure to the risk of pregnancy of 3 months) was characterised by a significantly higher median concentration of spermatozoa which exhibited slow linear or nonlinear motility. This confirms the findings of a previous study which suggested that slow linear or nonlinear motility are superior forms of spermatozoal motion.     

美托洛尔两种光学异构体代谢的酶动力学研究

目的：建立一种用AUC对酶动力学模型参数进行估算的方法，用酶动力学模型对美托洛尔（Met）两种光学异构体在大鼠肝脏的药物代谢进行研究。方法：用数学方法推导参数估算法公式；用大鼠肝切片孵育技术，对Met两种光学异构体的三种不同剂量（5、10、30μmol.L^-1）的药物浓度进行分析。并用本的参数估算法求出各自的酶动力学参数。结果：两种异构体，三种不同剂量的AUC有显性的统计学意义（P＜0．01），R－（＋）－Met的Vm,Km值分别为5．7471μmol.L^-1.h^-1和6．7724μmol.L^-1，S－（－）－Met的Vm,Km值分别为6．4350μmol.L^-1.h^-1和18．3404μmol.L^-1。结论：酶动力学模型适用于脏代谢的药动学研究。两种异构体的代谢具有明显差异。存在代谢的右旋异构体选择性。     

大肠癌巨─微血管构筑的临床研究

为了探讨大肠癌和其间质血管的关系，我们研究了48例大肠癌标本不同部位的巨─-微血管构筑。方法：用癌瘤标本造影摄X线片、立体显微镜和微机图象定量分析。结果显示：癌中心血管稀疏或为无血管的坏死区及血管破坏；癌远近端瘤组织内血管增多增粗，畸形及紊乱；其血管定量参数与癌中心和癌远近端肠粘膜相比有显著差异（P＜O．05，P＜0．01）。结论：①大肠癌的发生发展依赖于血管形成和细胞增殖。②在理论上解释了大肠癌的临床病理过程。③大肠癌的恶性程度与其血管密度间似有负相关的趋势。④探讨了其临床应用价值。     

中药制剂过程的建模、优化与应用研究

本文以中药滴剂生产过程的优化为目标,以某大型中药集团企业的滴剂生产过程为背景,为实现滴丸制剂过程数字化进行了理论与应用上的探索,其中,为制剂过程建立了多个机理模型:通过辨识建立数据模型,对生产过程进行分析,给出了相应的优化方案;对难以直接测量的滴制速度这一关键参数,提出了多种软测量算法,利用粒子群算法优化模糊控制器,构建了一个实用的滴速模糊控制系统;设计与构建了数据采集分析平台和制剂过程生产测控系统。     

一类单调似然比分布族

该文给出了一类分布族为单调似然比分布族的条件,从而可知非中心的分布族和非中心的分布族均为单调似然比分布族.     

不同血细胞分析系统间检测结果的偏差评估及应用

目的 分析同一临床实验室不同型号的血细胞分析仪的性能特点，并对其检测结果进行评估，对有偏差的项目进行调整，使同一实验室不同型号的血细胞分析仪的检测结果具有可比性。方法 对本实验室所使用的Sysmex KX-21、Sysmex SE-9500和Beckman Coulter Ac．T 5diff三台血细胞分析仪的准确度、精密度、线性度分别进行评价，选定其中一台指标最优的仪器作为比对仪器，将另外两台仪器的血细胞参数进行调整。结果 因Sysmex KX-21的WBC、RBC、HGB及PLT四项指标的准确度、精密度、线性度均较理想，故选为比对仪器。Sysmex SE-6500和Beckman Coulter Ac．T 5diff有部分指标的部分评价项目与Svsmex KX-21有偏差。对有偏差的项目进行调整后，三台仪器的四项指标的相关系数的平方均不低于0．95。结论 同一实验室在使用不同型号的血细胞分析仪时，应对其进行相互校准。校准后，保证三台仪器的检测结果具有可比性。