Bovine leukocyte adhesion deficiency--clinical course and laboratory findings in eight affected animals

To compare multiple and singleton pregnancies in the treatment of threatened preterm delivery with prolonged intravenous ritodrine, 32 women with multiple pregnancy (26 twins, 6 triplets, 70 fetuses, 30.3 +/- 3.5 weeks) and 51 women with singleton pregnancy (31.3 +/- 2.6 weeks) admitted for threatened preterm delivery without rupture of the membranes were the subjects of a retrospective study of obstetric data, perinatal outcome and maternal adverse effects. Significance was assessed by chi 2 test and Student's t test. Multiple pregnancies were associated with a marked increase in the duration of tocolysis (17.2 +/- 17.3 vs. 7.6 +/- 8.1 days, P < 0.01), incidence of delivery before 37 weeks (87.5 vs. 35.3%, P < 0.01) and incidence of maternal cardiovascular complications (34.4 vs. 4.0%, P < 0.01), including three cases of pulmonary edema. The incidences of delivery before 32 weeks (12.5 vs. 7.8%) and of neonatal death (2.9 vs. 0%) were not significantly different in the two groups. Multiple pregnancies dramatically increased the incidence of maternal adverse effects of prolonged intravenous ritodrine therapy. Neonatal benefit is questionable and was difficult to establish since it was not a randomized study.     

Immunogenetics of the A-E alloantigen complex

OBJECTIVE: To examine noradrenergic (NA) function in children with attention-deficit hyperactivity disorder (ADHD) by replicating and expanding upon a previous finding that ADHD children with and without reading disabilities (RD) differ in plasma levels of the NA metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG). METHOD: Plasma levels of MHPG were compared in ADHD children who were subdivided on the basis of the presence or absence of RD. Subsequently, this replication sample was combined with a previously studied sample to further explore the relationship between plasma MHPG levels and measures of cognitive function in children with ADHD. RESULTS: Plasma levels of MHPG were significantly lower in ADHD children without RD, compared with those with RD, replicating a published finding. Analyses in the combined sample indicated that, among children with ADHD, plasma MHPG levels were inversely associated with measures of academic achievement and verbal processing, but not parent or teacher ratings of behavior or continuous performance test measures of attention and impulsivity. CONCLUSIONS: These data indicate that children with ADHD are not homogeneous with regard to NA function and that neurochemical variation is closely associated with differences in clinical characteristics of the children.     

磺酸型介孔材料催化合成甲基葡萄糖苷

以甲醇和葡萄糖为原料,采用一步合成法合成甲基葡萄糖苷。以磺酸型介孔材料作为催化剂,借助扫描电子显微镜、高分辨率透射电子显微镜、低温氮气吸附/脱附、热重分析等方法研究了材料的结构和性能。实验结果表明,催化剂用量为0.6g,醇糖摩尔比为28∶1,反应温度为115℃,反应时间为2 h为最佳反应条件,此条件下合成产物的收率可达95.67%。同时使用Fourier红外光谱仪对产物进行了表征。     

邻苯二甲酸氢钾-硼酸盐电解液中AZ91D镁合金的阳极氧化(英文)

研究 AZ91D 镁合金在邻苯二甲酸氢钾-硼酸盐碱性环保型电解液中的阳极氧化行为。考察邻苯二甲酸氢钾对阳极氧化膜层性能的影响,并利用扫描电镜(SEM)、X 射线衍射(XRD)、动电位极化和电化学阻抗(EIS)进行分析表征。结果表明,邻苯二甲酸氢钾的浓度对阳极氧化成膜过程,氧化膜的表面形貌、厚度、相结构和耐腐蚀性能都有重要影响。在硼酸盐电解液中加入适量的邻苯二甲酸氢钾以后,制得的阳极氧化膜表面光滑、致密,与镁合金基体的结合力强,具有优异的耐腐蚀性能。     

SBR的纳米级分散对聚丙烯力学性能的影响

利用ISBS方法制备PP/纳米SBR复合材料。通过SEM和力学性能测试,研究了纳米SBR在复合材料中的分散状况,并考察了不同纳米SBR的添加对PP力学性能的影响。结果表明:纳米SBR在基体PP中实现了纳米级分散;且纳米SBR的添加量为7%时,复合材料PP/纳米SBR的力学性能最佳,其中缺口冲击强度提高了80%。     

ABS塑料三价黑铬电镀工艺与故障处理

介绍了ABS塑料电镀三价黑铬的工艺流程,主要包括除油,亲水,粗化,中和,预浸,催化,加速,化学镀镍,活化,镀铜,微蚀,镀光亮镍,镀三价黑铬,钝化和烘干.给出了三价黑铬镀液的配方,阐述了各组分的作用及工艺奈件对镀层的影响,介绍了常见故障的处理方法.     

电石装置供电系统的改进

宁夏西部聚氯乙烯有限公司在电石装置供电系统中安装过电压吸收装置、限流电抗器和接地消弧自动跟踪补偿装置,避免了供电系统过电压、短路电流和电容电流对电气设备的危害,生产1 t电石耗电量由3 579.25 kW·h降到3 553.89 kW·h.     

Organofluorine Hydrazone Derivatives as Multifunctional Anti-Alzheimer's Agents with CK2 Inhibitory and Antioxidant Features

A set of novel hydrazone derivatives were synthesized and analyzed for their biological activities. The compounds were tested for their inhibitory effect on the phosphorylating activity of the protein kinase CK2, and their antioxidant activity was also determined in three commonly used assays. The hydrazones were evaluated for their radical scavenging against the DPPH, ABTS and peroxyl radicals. Several compounds have been identified as good antioxidants as well as potent protein kinase CK2 inhibitors. Most hydrazones containing a 4-N(CH₃)₂ residue or perfluorinated phenyl rings showed high activity in the radical-scavenging assays and possess nanomolar IC₅₀ values in the kinase assays.     

机构输入与识别系统的研究——机构创新设计系统研究之三

介绍了机构创新设计系统以两种方式输入简图作为构型设计的原形。一种是在系统界面环境直接点击专用菜单绘制简图；一种方式是由设计者提供手绘草图或图纸，通过图像处理和模式识别技术，实现草图的获取，转化为系统机构绘制单元组成的简图。机构生成模块对简图可以进行自动识别纠错，保证机构的合理性，得到完整的机构信息。机构输入系统的实现，奠定了机构创新设计的自动化、智能化基础。     

Predicting suspended sediment concentration from nephelometric turbidity in organic‐rich waters

Nephelometric turbidity is an optical index for the side scattering of light caused by fine particles suspended in water. When a mixed composition of suspended inorganic and organic materials, including dissolved organic material, is present, turbidity measurements can be affected by the different optical properties of the organic and inorganic materials present, and different turbidimeters are more or less sensitive to these influences. Two different methods of nephelometric turbidity measurement were assessed (using instruments confirming to two different turbidity standard methods: EPA 180.1 and ISO 7027). We investigated the influence of particulate organic matter and coloured dissolved organic matter on relationships between turbidity and suspended sediment concentration for rivers in diverse Otago catchments, in the South Island of New Zealand. The presence of organic matter and dissolved colour affected turbidity measurement owing to light absorption; however, turbidity measurement following the ISO 7027 standard, which specifies near infrared radiation at wavelengths where organic absorption is very weak, was less affected by organics. As a result, rating equations between suspended sediment and turbidity may be significantly different with ISO 7027 compared with EPA 180.1 methods.