禽流感病毒核蛋白单克隆抗体的制备及部分特性鉴定

目的：制备抗禽流感病毒（AIV）核蛋白（NP）的单克隆抗体（mAb）并进行特性鉴定。方法：分别用甲醛灭活的和TritonX-100裂解的AIV H9N2及AIVNP基因的原核表达产物免疫BALB／c小鼠。经细胞融合、间接ELISA筛选及克隆化，建立能稳定分泌抗AIV NP mAb的杂交瘤细胞株。mAb的效价采用间接ELISA测定，用交义反应试验及间接免疫荧光染色法检测mAb的特异性。结果：经细胞融合、筛选及克隆化，间接ELISA法测定，mAb共得到6株能稳定分泌抗禽流感病毒NPmAb的杂交瘤细胞株，分别命名为4F4、1C3、1G11、1C2、1D10及2E7。1G11、1D10腹水的ELISA效价最高，分别为2^-13和2^-14。交叉反应试验及间接免疫荧光染色检测表明，两株mAb的特异性良好。结论：其获得6株抗AIVNP的mAb，其中2株mAb1C11和1D10的效价最高，特异性良好，为AIV的研究及快速诊断方法的建立奠定了基础。     

Accounting for susceptibility in risk assessment: The need for full disclosure

Many Environmental Laws create the unrealistic expectation that science can be used to determine ‘safety'. The many uncertainties surrounding environmental risks, as well as individual, group and societal differences about what is considered ‘safe', make it inevitable that policy decisions must be made. It is appropriate that such decisions be shaped by politics and social issues, as well as be informed by science and economics, but care should be taken to distinguish between policy and fact. Not much is known about the nature and magnitude of environmental susceptibilities. Credible environmental decisions require that scientists, risk assessors and decision-makers acknowledge this, and that they take care to distinguish policy calls from scientific fact.     

Surface Modification of Poly(lactide-co-glycolide) Nanospheres by Biodegradable Poly(lactide)-Poly(ethylene glycol) Copolymers

The modification of surface properties of biodegradable poly(lactide-co-glycolide) (PLGA) and model polystyrene nanospheres by poly(lactide)-poly(ethlene glycol) (PLA:PEG) copolymers has been assessed using a range of in vitro characterization methods followed by in vivo studies of the nanospheres biodistribution after intravenous injection into rats. Coating polymers with PLA:PEG ratio of 2:5 and 3:4 (PEG chains of 5000 and 2000 Da, respectively) were studied. The results reveal the formation of a PLA: PEG coating layer on the particle surface resulting in an increase in the surface hydrophilicity and decrease in the surface charge of the nanospheres. The effects of addition of electrolyte and changes in pH on stability of the nanosphere dispersions confirm that uncoated particles are electrostatically stabilized, while in the presence of the copolymers, steric repulsions are responsible for the stability. The PLA:PEG coating also prevented albumin adsorption onto the colloid surface. The evidence that this effect was observed for the PLA:PEG 3:4 coated nanospheres may indicate that a poly(ethylene glycol) chain of 2000 Da can provide an effective repulsive barrier to albumin adsorption. The in vivo results reveal that coating of PLGA nanospheres with PLA:PEG copolymers can alter the biodistribution in comparison to uncoated PLGA nanospheres. Coating of the model polystyrene nanospheres with PLA:PEG copolymers resulted in an initial high circulation level, but after 3 hours the organ deposition data showed values similar to uncoated polystyrene spheres. The difference in the biological behaviour of coated PLGA and polystyrene nanospheres may suggest a different stability of the adsorbed layers on these two systems. A similar biodistribution pattern of PLA:PEG 3:4 to PEG 2:5 coated particles may indicate that poly(ethylene glycol) chains in the range of 2000 to 5000 can produce a comparable effect on in vivo behaviour.     

多检测GPC/SEC技术在高分子表征中的应用Ⅳ.氘化高分子的溶液性质

采用体积排斥色谱法／ 示差折光指数／ 直角激光光散射／ 示差粘度三检测联用技术表征了氘化聚苯乙烯、聚苯乙烯和氘化聚苯乙烯－ 聚异戊二烯。结果表明,在θ条件下,虽然氘化聚苯乙烯的化学依赖性常数υＴ,ＤＰＳ比聚苯乙烯的化学依赖性常数υＴ,ＰＳ大,但２５ ℃时在四氢呋喃中,氘化聚苯乙烯的分子尺寸仍小于聚苯乙烯的分子尺寸。由于嵌段共聚物的淋洗体积随组成变化,所以用传统的ＳＥＣ／ＲＩ得不到准确的分子量。经比较膜渗透、小角激光光散射和基质辅助激光脱吸与离子化时间飞行质谱等的实验结果,证明体积排斥色谱法／ 示差折光指数／ 直角激光光散射／ 示差粘度三检测技术能准确地得到氘化二嵌段共聚物的分子量以及其它重要信息。     

Comparison of the protein and DNA approaches for the characterization of a β-globin chain variant,hemoglobin Cocody [β21 (B3) Asp- → Asn], in a Caucasian patient

Summary Over the past few years, the methodologies used for the identification of hemoglobin A variants have been greatly improved. Both the protein- and DNA-based strategies have their own advantages and limitations. In this report we illustrate the use of both assays for the characterization of a hemoglobin Cocody variant in a woman of Spanish descent. After evaluating the mobility value matrix of the abnormal hemoglobin, the amino acid transition was determined by HPLC and microsequencing of the protein. The ₂₁ Asp was shown to be substituted by an Asn. At the DNA level, the only nucleotide replacement responsible for this amino acid substitution is GAT- AAT at codon 21. The analysis of the-globin gene by denaturing gradient gel electrophoresis (DGGE) method showed that the mutation was situated in a fragment including exon 1. The hemoglobin variant was then identified to be hemoglobin Cocody by DNA sequencing of this fragment.     

机械传动系统的模糊分析设计

用线性隶属函数、二元相对比较级等确定特征因素的隶属度,构造了不同机械传动类型的模糊子集,取其与待识别模糊子集向量空问的距离均数为贴近度。根据择近原则选择确定机械传动类型。     

膨胀型肝癌的超声影像、病理特征及其临床意义探讨

目的：研究膨胀型肝癌的超声表现、病理形态及其临床意义间的关系。方法：对700例肝细胞癌患者术前超声检查与术后切除标本的病理及术后生存情况进行分析。结果：按照Nakashima分型，膨胀型420例，浸润型280例。与浸润型肝癌不同，膨胀型肝癌有4种独特超声表现，分别称之为弱回声型、声晕型、外生型和小结节型，它们分别有不同的病理基础。膨胀型肝癌的发生率虽不高，但其手术切除率却非常显著高于发生率较高的浸润型肝癌（P＜0．01）。结论：膨胀型肝癌是一类有明显临床意义的肝细胞癌，术前超声诊断有助于临床重点治疗。     

白术挥发油/β-环糊精包合物的表征

 目的　有效表征白术挥发油/β-环糊精(β-CD)包合物。方法　采用X射线粉末衍射、扫描电镜、差热分析、红外光谱等手段,研究白术挥发油/β-CD包合前后理化性状等的变化。 结果　与β-环糊精相比较,包合物在X射线粉末衍射、扫描电镜、差热分析以及红外光谱等方面存在显著差异。结论　白术挥发油/β-CD包合物形成后具有明显的特征,可表征包合的形成,同时为包合物制剂学研究和质量控制提供依据。     

PHYSICO-CHEMICAL CHARACTERIZATION OF SEED OIL AND NUTRIENT ASSESSMENT OF ADENANTHERA PAVONINA, L: AN UNDERUTILIZED TROPICAL LEGUME

Analysis showed the seeds of Adenanthera pavonina contained appreciable amounts of proteins (29.44g/100g), crude fat (17.99g/100g), and minerals, comparable to commonly consumed staples. Total sugar was low (8.2g/100g) while starch (41.95g/100g) constitutes the major carbohydrates. Low levels of antinutrients were reported and methionine and cystine were the most deficient amino acids. Linoleic and oleic acids make up 70.7 percent of the total fatty acids. Free fatty acid levels were relatively high but peroxide and saponification values of 29.6mEqkg^-1 and 164.1mgKOHg^-1respectively point to a resemblance to oils processed for food. It was concluded that A. pavonina seeds represent a potential source of oil and protein that could alleviate shortages.     

具有高临界相转变温度的热敏性高分子材料

介绍了一类具有高临界相转变温度(UCST)的热敏性高分子材料,并对其相转变机理、热敏性影响因素及表征方法做了讨论。UCST类高分子材料的热敏性受到相对分子质量、疏水基团、溶液中的质子受体/给体、电解质等多种因素的影响。当UCST类高分子材料与具有最低临界相转变温度(LCST)的高分子材料共聚后,可得兼具UCST和LCST特点的新型功能材料,拓展了热敏高分子材料的应用领域。