Mutant induction through adventitious buds of Kohleria

Summary Freshly cut leaves of Kohleria eriantha and K. x Longwood were exposed to a wide range of gamma irradiation doses and allowed to root and form adventitious buds. K. Eriantha could not be successfully propagated from leaf half cuttings. Longwood produced a small number of adventitious plantlets as compared to other Gesneriads. Colchicine treatments reduced leaf half survival in Longwood by more than 50%. Leaf halves exposed to low and moderate doses of gamma irradiation showed increased overall plantlet production compared to nonirradiated leaf halves.Of the mutation parameters calculated, the number of mutants per 100 surviving leaf halves appears to be the most useful since it relates the number of mutants within a dose to the number of surviving leaf halves, the number of mutants to the number of plants produced, and the number of mutants within doses to control values.Using the criteria, number of mutants per 100 surviving leaf halves, optimum production of all mutants, of useful and of dwarf mutants was obtained at 2.5 kR for noncolchicine treated leaf halves and 1.5 to 3.0 kR for colchicine treated leaf halves.Of the adventitious plantlets produced, 13.8% were classified as mutant types. Mutant plants were found in radiation dose levels up to 5.5 kR. The array of mutants produced was skewed toward plant habit and flower characteristic mutants with several leaf characteristic, lethal, and polyploid mutants observed. A high frequency of mutants, 10 of 93 plants, occurred in the nonirradiated controls. Four sectorial chimeras were identified from both control and irradiation exposed groups. Several potentially useful flower color and dwarf mutants have been selected for further study. Adventitious buds may have developed from callus at petiole and leaf-vein bases. Colchicine treatments severely inhibited adventitious plantlet production and because of this could not be used as a criterion to identify the origin of adventitious buds. Conclusive determination of the organogenesis of adventitious buds from Longwood leaf halves could not be made. Mutant plantlets formed from adventitious buds on detached leaf halves of Longwood appear to arise from single cells as has been found with other Gesneriads.Scientific Journal Series Article No. 10 330 of the Minnesota Agricultural Experiment Station.     

Terrestrial Ecotoxicity of Eight Chemicals in a Systematic Approach (7 pp)

Background and Objective   Terrestrial ecotoxicity data are required for many research purposes. The data are derived either from the literature or elaborated by own investigations. As the terrestrial toxicity tests are usually time-consuming and labour intensive, the experiments are performed with a limited number of test organisms and soils. In the context of a project sponsored by CEFIC-LRI (European Chemical Industry Council – Long-Range Research Initiative), EC50-values were systematically elaborated for eight chemicals with a wide range of logKow-values (CdCl2, Trinitrotoluene, 3,4-dichloroaniline, 2,4-dichlorophenol, Tributyltinchloride, Pentachlorophenol, Benzo(a)pyrene, p,p-dichloro-2,2-diphenyl-1,1,1-trichloroethane). The substances were selected covering a broad range of physico-chemical and ecotoxicological properties. As toxicity endpoints, microbial activities, plant germination and growth as well as reproduction of earthworms and collembola were determined. As such systematic investigations are rarely performed and for some substances no data existed, the data pool is made available to the scientific community.Methods   All toxicity tests were conducted on three different soil types (sandy soil, silty soil, loamy soil), according to ISO and OECD guidelines Results, Discussion, Conclusion and Outlook   The different toxicities of the chemicals, the influence of soil properties on bioavailability as well as different sensitivities of test organisms and test parameters are reflected by the EC50-values. The results showed that the EC50-values calculated on the basis of nominal concentrations can significantly vary from EC50-values derived from analytical concentrations for some substances. To avoid false conclusions, this has to be considered especially when concentrations determined in the field are compared with toxicity data obtained from the literature or calculated on the basis of nominal concentrations. Moreover, the results indicate that terrestrial ecotoxicological tests should be accompanied by chemical analyses, to be sure to derive sound EC50-values. As the tests were performed according to international guidelines, the comprehensive data pool relevant for the terrestrial ecotoxicity of eight chemicals is considered to be of great value for further research and discussions dealing with the habitat function of soils.     

聚乙二醇对五硼酸铵改性结构刨花板吸水性能的影响

试验引入聚乙二醇改性体系以补偿五硼酸铵处理结构刨花板时造成物理力学性能的降低,并研究了处理后结构刨花板的吸水性能。结果表明：24h吸水厚度膨胀率和24h吸水率这两项指标与五硼酸铵添加量的相关性最大,该两项结果均随五硼酸铵添加量的增加而增大。聚乙二醇种类对结构刨花板吸水性的影响大于添加量的作用。尤其是24h吸水率,4个添加量水平下的结果均无显著性差异。     

Organochlorine and Metal Accumulation in Fish (Phoxinus phoxinus) Along a North-South Transect in the Alps

Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification.     

鸡肝碱性磷酸酶的分离纯化及其部分性质的研究

经过匀浆、正丁醇处理、硫酸铵分级分离、DEAE-纤维素离子交换柱层析、SephadexG-75凝胶过滤等步骤,从鸡肝中部分纯化了碱性磷酸酶。以对硝基苯磷酸二钠(PNPP)为底物,测得该酶的最适pH为10.5,最适温度为40℃,Km=0.521mmol·L-1。甲醇、乙二醇与丙三醇均对其活性有不同程度的抑制作用。     

竹纤维增强聚丙烯复合材料的研究

研究了竹纤维增强聚丙烯复合材料的力学性能、热学性能、加工性能,采用电镜扫描分析了复合材料的界面及其微观结构.用多元统计分析中的主成分分析法,合理地确定竹纤维增强聚丙烯复合材料多项性能指标兼优的最佳纤维含量.     

Inv(13)(p12 q14)一家系报道

先证者女汉族24岁,身高1.61米.体重60.1公斤。因连续生两胎畸形儿夭折就诊。第一胎为足月顺产,唇裂、腭裂.双脚各为6趾,50天时因呼吸道感染而死亡。第二胎.足月顺产,体征似第一胎,生下两天死亡。外周血染色体检查,分别计数50个细胞,G 显带分析20个核型均为46,xx.Inv(13)(p12 q14)臂间倒位.患者父亲及其兄长核型与患者相同。其丈夫体征与核型均正常。其姐、妹及母亲因居住内地未查,患者哥及姐所生子女表形均无异常。     

MDM2和p53在大肠癌组织中的表达及其意义

目的：探讨抑癌基因mdm2、p53在大肠癌组织中表达情况及与临床病理之间的关系。方法：采用免疫组化SABC法检测大肠癌79例,大肠腺瘤样息肉34例,正常大肠粘膜组织15例中MDM2、p53的表达。结果：MDM2在正常大肠组织、大肠腺瘤、大肠癌中表达阳性率分别为6.67%（1/15）、41.18%（14/34）、63.29%（50/79）;p53阳性率分别为0、35.29%（12/34）、67.09%（53/79）。MDM2、p53在正常组织、大肠腺瘤、大肠癌组织中表达率逐渐增加（P〈0.01）,两者与DukesC期、D期及远处转移相关,与年龄、性别及组织细胞分化程度无关。MDM2与p53表达之间呈正相关。结论：MDM2、p53高表达与大肠癌的发生、发展和预后相关。     

猪肉中增瘦倍多肉残留量测定

本文将电荷转移分光光度法用于新型猪饲料添加剂——增瘦倍多肉的测定。以碘-二氯乙烷作为电荷接受体,选择293.5nm作为检测波长,在1～25ppm服从Beer定律。其回收率为91％～106％。并首次报告了不同饲喂条件下猪肉中的残留量。