MITOCHONDRIAL DNA POLYMORPHISM IN CHINESE

Human mitochondrial DNA (mtDNA) restriction endonuclease fragment patterns were analyzed using placenta DNA isolated from 273 individuals representing four different nationalities, the Han, the Uygur, the Kazakh and the Hui populations. Thirty-eight fragment patterns (morphs) were observed with the enzyme ApaI, BamHI, EcoRl, HindIII, HinfI, HhaI, HapII, KpnI, MboI, PstI, PvuII, SacI, ScaL and XhoI. Fourteen new morphs, including some only existing in individual racial and national populations were observed, which indicates that there is a significant difference in the distribution of mtDNA morphs among various national and racial populations. By comparison with the mtDNA sequences in primate species, some mtDNA ancestral morphs were found to be retained in Oriental population today. This result provided indirect evidence that Asia may be one of the human original sources. Genetic distances among four national populations computed and employed in construction of an average linkage tree suggested that the     

A NEW SILENT MUTATION FOUND IN THE CHINESE PAH LOCUS AND ITS ROLE IN THE PRENATAL DIAGNOSIS OF PHENYLKETONURIA

A silent mutation or sequence polymorphism, A to T substitution at codon 399 in exon11 of the PAH gene from a Chinese PKU patient, was found by sequence analysis. The fre-quencies of this new mutation in normal and abnormal (PKU) genes were 0.005 and 0.09,respectively, based on the analyses of 100 normal individuals and 39 PKU patients usingDNA amplification with polymerase chain reaction (PCR) and oligonucleotide hybridizationmethods. This silent mutation can be used as a "genetic marker" for PKU prenatal diagno-sis. Recently, a fetus at risk for PKU, who could not be completely predicted by RFLPslinkage analysis, was prenatally diagnosed with this genetic marker.     

硅藻土表面酸性质的研究

研究了几种硅藻土的表面羟基结构、表面酸性质及其孔结构，发现除浙江白土表面具有双生的硅羟基外，其他只有连生与孤立的硅羟基；硅藻土中均存在少量的Ｂ酸和Ｌ酸；硅藻土酸性质及经ＮＨ４Ｃｌ或ＨＣｌ活化后的酸性质变化与硅藻土孔结构、表面结构有关。焙烧温度升高，硅藻土酸强度增加，酸量减少。     

负载肝素及生物素化肝素修饰的纳米粒子的基质介导基因传递系统

首先通过静电作用将带负电荷的肝素及生物素化肝素和带正电荷的PAMAM/DNA自组装,分别制备了PAM AM/DNA/heparin和PAMA M/DNA/heparin-biotin复合物,然后用快速降解胆酸功能化星型聚(DL-丙交酯)作为基质、并加入水溶性高分子α,β-聚(N-2-羟乙基)-L-天冬酰胺(PHEA)作...     

STUDY ON BclI/St14 RFLPs IN CHINESE FOR DNA DIAGNOSIS FOR HEMOPHILIA A

The BclI polymorphism within DXS52 (St14) was reported. It was composed of 4 allelic fragments 4.0 kb, 3.3 kb, 3.0 kb and 2.3 kb, The frequency of these fragments were 0.09, 0.12, 0.44 and 0.35 respectively in the Chinese. The polymorphism provided the PIC of 0.66. DNA analysis of families, with hemophilia A showed that the confidence of the RFLPs was the same as the TaqI/St14 RFLPs and for carrier detection the former is much better than that of the TaqI/St14 RFLPs.     

大孔吸附树脂技术应用于复方中成药制备工艺的研究

本文报告了用非极性大孔吸附树脂法从复方中药中提取分离有效成分的研究。结果表明，正确地选择大孔吸附树脂及吸附和解吸条件，可得到高纯度的有效组分，其粘度低，有利于制剂。     

MAGNETIC SUSCEPTIBILITY OF CHINESE LOESS AS A PALAEOCLIMATIC INDICATOR

Through the studies on low temperature susceptibility, frequency dependent susceptibility, isothermal remanent magnetization, low temperature magnetization and demagnetization for loess and palaeosols one can easily reveal some significant characters of rock magnetism for the magnetic minerals of ultrafine grain sizes, those are very difficult to identify by general geological methods. It is shown in the present study that both loess and palaeosols cover magnetic grain size from superparamagnetism, single domain to multidomain. Loess samples with relative high peramagnetic minerals are dominantly of thermally stable characteristics while palaeosols have relatively high percentage of superparamagnetic grain (0.01—0.03μm). The relative grain size of magnetite is always finer in palaeosol with higher susceptibility than in loess, indicating that many tiny ferri-ferromagnetic minerals formed during the process of soll formation, which has caused a higher susceptibility in palaeosols than in loess. The cli     

EXPRESSION OF A ZEIN GENE (Z4) INTRODUCED INTO DICOTYLEDONOUS Solanum nigrum

A maize genomic clone containing a zein gene (Z4) is inserted into the T-DNA of the Ti plasmid pTiT37. Agrobacterium tumefaciens strain harboring this modified Ti plasmid is used to infect stem sections of young plants or explants of dicotyledonous Solanum nigrum. Axenic transformed calli active in nopaline synthesis are obtained and transgenic plants are differentiated from them DNA Southern hybridization and RNA dot-hybridization analyses show that the zein gene is really transferred and integrated into the nuclear genome of transformed Solanum nigrum and that the zein gene can be transcribed into mRNA in the transformed calli and shoots. But the presence of the zein protein cannot be detected in either the transformed calli or the transgenic shoots. The results of thte experiments demonstrate that the promoter of a gene from monocotyledonous plants can function normally in transgenic dicots. The possibility of developmentally-regulated expression of the zein gene in transformed dicots is discussed in     

一种新型低毒安全香烟添加剂的研究

一种新型低毒安全香烟添加剂的研究崔学文（四川三峡学院化工系万县６３４０００）关键词低毒安全香烟,香烟添加剂流行病学、动物实验、人体病理解剖研究结果表明,吸烟与许多疾病的发生呈正相关关系,与吸烟有关的主要疾病有：肺癌,支气管炎,肺气肿,口腔癌,膀胱癌,...     

乙烯基乙炔氢氯化反应合成氯丁二烯催化剂的研究

乙炔法氯丁橡胶单体2-氯丁二烯—1,3(简称氯丁二烯或CB)生产目前国内和日本电气化学公司等仍采用传统的Nieu land型催化剂,由乙烯基乙炔(MVA)氢氯化制得。但存在二氯丁烯等副产物生成量大,选择性低,消耗高,污染环境等问题。国内外有一些氯丁二烯合成催化剂改进的专利报道,本文对氯丁二烯合成催化剂也进行了研究,得到有益的结果。     

乳化液膜清除分离胆红素的研究

以液体石蜡为膜相,司班８０为表面活性剂,乙酸乙酯为转移载体,氢氧化钠水溶液为内相制备了一种新型的乳化液膜,用于清除分离对人体有害的胆红素,其分离过程具有不可逆的特点,分离的速度快,清除率高,对游离胆红素的清除率为９９．８％,对未结合胆红纱的清除率为８３．０％,分离的速度和清除率优于其他分离方法。     

A NUMERICAL STUDY ON THE MECHANISM OF BLOCKING HIGH FORMATION

Numerical integration is performed of the KDV equation of the forced dissipation with the result that it takes about 10 days to transform a high-index circulation into a blocking pattern, in whose establishment and maintenance the thermal forcing and dissipation, nonlinoear advection, and linear dispersion are equally important and serve as three factors of essentiality.     

A STUDY ON THE STRUCTURAL EFFECT OF DOUBLE-BRIDGED CONJUGATIVE SYSTEMS

In this paper, the following carbonyl-imino bridged compounds and related analogs havebeen synthesized:X= C1, m = 0); and the structural effect of the carbonyl-imino bridges has been studied by means of the UV and other properties of the compounds. A new conception of conjugative segment is put forward. The structural bases for each of the three π-π* bands of (C) are ascertained and verified by modification on structure of segments, such as eliminating, merging, lengthening or shortening of segments. It is demonstrated that both bridges -CO-and -NH- can block the conjugated polarization of the whole molecule so as to form three segments S, M and L of which the λmax each exhibits relative independence. The electronic absorption peaks resulting from different segments can be readily recognized and the existence of each segment can be ascertained. This may provide a new way for structural analysis of bridged compounds.     

硝基胍热解反应途径的量子化学研究

本文用MINDO/3方法研究了硝基胍热解反应的机理。研究结果表明, 硝基胍热解反应可经历两条途径得到主产物(N_2O、H_2O和NH_3)。这两条途径相互竞争, 但生成N_2O及H_2O的途径Ⅰ要容易进行, 是整个反应的启动步。     

大孔球形纤维素固定化单宁的性能表征及其在黄酒中的应用

将单宁酸偶联在大孔球形纤维素载体上,制成一种新功能高分子材料-大孔球形纤维素固定化单宁。使用压汞法进行结构测定,发现其具有良好孔结构,平均孔径70nm,比表面积161.39m2/g,孔容13.53ml/g。流速与压力曲线表明,固定化单宁水力学特性好,可以耐受0.7Mpa的操作压力。化学溶剂浸泡实验表明,固定化单宁具有良好的化学稳定性和不溶性,符合食品用品的国家标准。800ml黄酒通过4ml固定化单宁层析柱处理,酒液清亮透明,保留原酒的香味和口感。蛋白质分离检测仪检测通过固定化单宁柱的酒液,高、中分子量的蛋白质大大减少,其中分子量在1万以上的蛋白质较未处理的酒液减少了65.7%。酒液化学成分分析显示,蛋白质的总量下降了33.4%,而氨基态氮却不变;铁离子含量由7.79×10-8mol/L降低至5.89×10-9mol/L,而且其他成分没有变化,所有指标均达到黄酒的国家标准。高温强化试验和低温贮藏试验表明,经固定化单宁层析柱处理的黄酒具有很好的稳定性。固定化单宁柱经0.1mol/LHCl洗脱再生,可以重复使用多次,而且保持性能稳定。     

L-酪氨酸在732阳离子交换树脂上吸附平衡与动力学研究

研究搅拌槽中732阳离子交换树脂吸附L-酪氨酸的交换平衡和动力学特性,考查了搅拌速度、温度、料液初始pH值、树脂粒径和料液初浓度对离子交换过程的影响.在研究的温度和浓度范围内,该离子交换等温线符合Henry等温式.搅拌速度为350rpm时,可以将外传质阻力忽略.料液初始pH值介于2.5～5.5 时,对交换量影响不大,而料液中Na 的存在会降低树脂的交换量.在忽略外传质阻力的条件下,采用不同粒径计算方法对动力学曲线影响很小.用间歇搅拌槽吸附动力学模型拟合出无外传质阻力条件下、不同初始浓度条件下离子交换的表面扩散系数Ds.结果表明,随着初始浓度的增大,Ds的数量级始终在10-8左右.     

D301树脂对酚类的吸附热力学研究

测定D301树脂对环己烷溶液中苯酚的吸附等温线，利用热力学函数关系计算了等量吸附焓，吸附自由能和吸附熵，等量吸附焓在30kJ/mol-35kJ/mol之间，推测吸附过程为氢键吸附。比较D301树脂对水溶液和环己烷溶液中苯酚的吸附性能，及D301树脂对环己烷溶液中苯酚和邻硝苯酚的吸附性能，进一步讨论了D301树脂对酚类物质吸附中的氢键作用。     

A STUDY ON THE CHEMICAL MECHANISM FOR POWDER CORROSION OF BRONZE ALLOY

A Cu-Sn-Pb alloy modelled after an antique was cast and the powder-corrosion (P-C) was prepared on it under simulated natural conditions. The main components of the corrosion are much like those of the ancient bronze powder corrosion. It is found that chloride, water and oxygen are the essential factors for P-C formation of which chlorine plays the most important role. According to the results of expriments and thermodynamic calculations, the chemical mechanism of the copper desease was studied. It is pointed out that the fast spread of P-C is caused by two vicious circles.     

A PRELIMINARY STUDY ON GENETICS AND TYPE FOR EARTH FOREST IN YUANMOU BASIN

The earth forest is a geomorphic type of the running water found in recent years in China. At some distribution regions of loose or semicemented fluviolacustrine facies strata, owing to scouring of rainstorm runoff, thousands of gullies and ravines and some stretches of earth columns were formed, like a stretch of forest observed at a distance, thus it was named earth forest.The earth forest landform developed the most typically in the Yuanmou Basin, Yunnan Province. Through the study, such as strata of fluviolacustrine facies, neotectonics, geomorphics, soil, climate, vegetation, etc., the authors pointed out the condition for forming the earth forest landform and its five development stages, and then divided it into four types: thin gully-earth gemma type, round basin-earth column type, broad gully column fort type and slope-remaining column type.     

一种亲水的酚羟基修饰聚苯乙烯树脂对酚类化合物的吸附热力学

在283-323K和研究的浓度范围内,苯酚、对甲苯酚、对氯苯酚和对硝基苯酚在亲水性的酚羟基修饰聚苯乙烯树脂（AM-1）与大孔吸附树脂（Amberlite XAD-4)上平衡吸附数据符合Freundlich吸附等温方程。酚类化合物在AM-1上的吸附容量比在Amberlite XAD-4上的吸附容量增加20%以上,这主要得益于AM-1表面的酚羟基入树脂的微孔结构。在较稀的溶液中AM-1对苯酚的吸附量比AmberliteXAD-4对苯酚的吸附量增加60%,表明AM-1对苯酚有特殊的选择性。Freundlich吸附等温线、相对吸附容量以及等量吸附焓表明,四种酚在两种树脂上的吸附是物理吸附过程。对酚类化合物被两种树脂吸附的吸附焓、自由能、吸附熵也作了测试,并对吸附行为作了合理的解释。