Ultrasound-Assist Extrusion Methods for the Fabrication of Polymer Nanocomposites Based on Polypropylene/Multi-Wall Carbon Nanotubes

Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 10¹³ to 10⁵ Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods.     

Les stratégies psychothérapeutiques

Psychological support is an essential concern in the management of alcohol misuses. Motivation and readiness to change are key factors of the evolution. They have to be in the centre of the patient-doctor relation. Regular evaluation is a part of a step by step therapeutic strategy.     

Comparison between a swim-up and a Percoll gradient technique for the separation of human spermatozoa

Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality.     

第一产程胎心监护异常226例的相关因素分析

目的探讨第一产程胎心监护异常的相关因素，提示处理措施。方法2004年1月1日。12月31日对我院226例第一产程胎心监护异常的相关因素进行回顾性分析。结果第一产程胎心监护异常为综合因素所致，胎儿高危因素为91.59％，母体高危因素为65．49％，产程处理因素为42．92％。结论第一产程胎心监护异常主要与胎儿因素、母体因素有关，提高产前检查质量、加强产程监护、正确选择分娩方式极为重要。     

Hepatic Disposition Characteristics of Electrically Charged Macromolecules in Rat in Vivo and in the Perfused Liver

The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E _ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E _ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested.     

人体经络静电荷检测研究

在经络静电荷检测基础上，研制了高灵敏微型电荷传感器系统。在１１２名正常自愿者的十二经脉五腧合穴和啼阳明胃经静电荷检测，发现正常状态下经络呈负电性（－７．８７×１０＾－３－－．６１×１０＾－１３Ｃ），经脉失衡度〈９．０６％；而在病理状态下（胃疾患）４５４例，经脉负电性小于正常人，失衡度在足三里穴达２４．０９％，稳定性差。又以胃电图离度（ＣＶ）分析，正常人空腹时，ＣＶ〈２０－３０％。胃疾患者ＣＶ〉３０     

不同海拔高度严重烧伤延迟复苏大鼠脑组织中能量负荷的变化及其意义

目的：探讨不同海拔高度严重烧伤延迟复苏大鼠脑组织能量负荷变化及其意义。方法：以120只雄性Wistar大鼠建立高原（海拔3800m）实验模型（TBSA30％，Ⅲ度），随机分为延迟、即时复苏组和正常对照组，分别于伤后1、6、12、24、72h及7d取材。兰州地区取相等数量动物重复实验。应用高效液相色谱法检测脑组织中AMP、ADP、ATP的含量，并计算能量负荷。结果：能量负荷在高原正常对照组与兰州地区正常对照组差异显著（P〈0．01）。高原烧伤后脑组织能量负荷与对照组相比均降低，即时复苏组伤后早期即出现显著变化（P〈0．01），伤后72h开始恢复，伤后7d差异无显著，延迟复苏组伤后7d仍星显著差异（P〈0．01）。与即时复苏组比较伤后6～24h无显著差异，伤后72h～7d呈显著性差异（P〈0．01）。高原地区各时相点与兰州地区比较，EC值均降低，除即时复苏组6h外，具有统计学意义。结论：不同海拔高度严重烧伤延迟复苏大鼠脑组织能量负荷的改变一定程度上反映了脑损伤的严重程度。     

Spécificités de la prise en charge postopératoire de l’enfant et de l’adolescent opéré du pied*

Resumé: Cet article inhabituel dans son fond et dans sa forme surprendra le lecteur. Il se propose de dérouler la chronologie de l’acte opératoire et de ses suites dans le cadre de la chirurgie du pied de l’enfant et de l’adolescent, et de l’analyser sous l’angle de la pratique quotidienne et non de la technique opératoire ou de l’évaluation des résultats; puis de confronter cette pratique aux demandes de la société (absence de douleur, rapidité du résultat, absence de complication et évaluation du résultat à l’égard du service à rendre). * Communication présentée au congrès SFMCP / AFCP de Biarritz les 20-21 mai 2005     

不良生活方式与高血压病的流行病学调查分析

目的:调查不良生活方式对高血压发病的影响。方法:以国际通用血压测量方法对全区15 384人进行整群随机抽样调查,着重对有、无不良生活方式的两组人群进行高血压患病率调查,及相对危险度(RR)、归因危险度(AR)、人群归因危险度(ARp)、U检验等的检测,以及相关及多元回归分析。结果:食盐量≥12 g/d高血压患病率31.6％,<12 g/d的为 4.4％(P<0.001,RR 7.3,AR 27.3,ARp 57.2％,r=0.8517);BMI>24高血压患病率 23.2％,<24者 6.4％(P<0.001,RR 3.7,AR 16.9,ARp 37.2％,r=0.3215);肥胖患病率 34.7％,无肥胖8.1％(P<0.001,RR 4.3,AR 26.6％,ARp 19.7％,r=0.3529);油腻饮食高血压患病率14.8％,非油腻饮食8.7％(P<0.001,RR1.7,AR 6.1,ARp 13.9％,r=0.3853);吸烟高血压患病率 12.5％,非吸烟 9.2％(P<0.001,RR1.4,AR 3.3,ARp 8.3％,r=0.8403);饮酒患病率 12.7％,非饮酒 9.4％(P<0.001,RR1.35,AR 3.3,ARp6.7％,r=0.4650)。为进一步了解各危险因子与高血压患病率之间的数量关系和对高血压影响作用的大小,对所有对象用年龄(15～80岁)进行了分组,龄差1岁,共66组,多元回归结果为:偏相关系数0.3775～0.0809,建立的统计模型达到极显著水平(P<0.001),复相关系数0.9525。6个回归因子中按对高血压患病率影响(偏相关系数)大小排序:     

农村公共卫生投融资机制存在的问题及对策

当前,农村公共卫生投融资规模不能适应农村居民的卫生服务需要,投融资结构不合理,致使投融资效果不佳,不利于农村卫生事业的发展。为此,需要从四个方面改革农村公共卫生投融资机制:一是要建立健全国家财政投资保障制度,发挥财政在农村公共卫生投资中的主体作用;二是要改革运行模式,拓宽融资渠道;三是要改善投资结构,优化资源配置;四是要创新管理体制,提高农村公共卫生服务能力。