广西余甘子叶导数光谱鉴别的研究

[目的]为广西余甘子叶的鉴别提供科学依据。[方法]采用紫外-可见光谱法。[结果]广西余甘子叶紫外-可见光谱法具有一定的光谱特征，且大多数回流液比冷浸液的吸收峰强。[结论]本研究可为广西余甘子叶的鉴别提供辅助手段。     

基质辅助激光解吸/电离飞行时间质谱在沙门菌检测和鉴定分型中的应用研究

目的利用基质辅助激光解吸/电离飞行时间质谱(MALDI-TOF-MS)对从门诊腹泻病人粪便分离的88株沙门菌进行检测分型。方法利用优化的MALDI-TOF-MS实验条件对沙门菌进行检测和鉴定分型,并与血清学分型、耐药分型和PFGE分型结果进行比较。结果在反映亲缘关系的差异水平值为100时,88株沙门菌被分为15个MALDI-TOF-MS型别。MALDI-TOF-MS分型结合耐药表型分型,可以将88株沙门菌分成44个亚型;MALDI-TOF-MS分型结合血清学分型,可以将88株菌分成46个亚型。MALDI-TOF-MS分型结合PFGE分型,可以将88株菌分成64个亚型。说明MALDI-TOF-MS在沙门菌分型中具有很好的分型能力。结论MALDI-TOF-MS方法在检测与鉴定食源性病原菌中具有稳定、重复性好的特点,可成为食源性致病细菌分析鉴定的重要工具。     

海龙类药材扫描电镜观察

对7种海龙类药材表面进行了扫描电镜观察,结果表明其种间区别明显,可以作为该类药材的鉴别依据。     

中药柴胡的药源调查及商品鉴定

通过对全国27个省区的药源调查和商品鉴定,较系统地整理了我国中药柴胡使用的原植物:共19种、5变种、1变型。并通过对102件柴胡商品的鉴定,发现其主流品种为:北柴胡、小叶黑柴胡、红柴胡和窄竹叶柴胡。     

钟乳鹅管石与珊瑚鹅管石的鉴别

本文从药材性状、光学显微性质及元素含量等方面,对目前市场上混用的二类“鹅管石”药材——钟乳鹅管石和珊瑚鹅管石进行了鉴别比较。表明二者不应混同入药。     

中药降香基原的研究

从文献查考、药材鉴别、理化分析和药理实验方面,将山油柑和降香黄檀作比较研究,二者相差很大,认为降香基原不能是山油柑。     

太子参及其伪品宝铎草的鉴别

对太子参与其伪品宝铎草根进行性状、横切成显微特征及紫外光谱比较鉴别。     

新的抗肿瘤抗生素云南霉素Ⅱ．提纯、理化性质与鉴别

自我国云南省土壤分离获得链霉菌菌株２３２１，并从该菌株的发酵液中提取分离到一个对肿瘤细胞有抑制作用的物质，该物质经鉴别与谷氏菌素相同，取名为云谷霉素。经过酸水解以后，可从中分离纯化得到一个活性成分。通过对其理化性质和光谱的测试分析，确认该成分为一个新的胞嘧啶核苷类抗生素，小鼠实验有显著的抗肿瘤作用，该抗生素定名为云南霉素（ｙｕｎｎａｎｍｙｃｉｎ）。     

Molecular identification of vectors of Leishmania in Colombia: mitochondrial introgression in the Lutzomyia townsendi series

The identity of the sandfly vectors of Leishmania braziliensis in Valle del Cauca Department, Colombia, was originally given as Lutzomyia townsendi, but then changed to L. youngi, another member of the L. townsendi series (Verrucarum group) with isomorphic females. To identify members of this series in Valle del Cauca, we analyzed the nuclear gene elongation factor-alpha (EF-alpha) and the mitochondrial gene cytochrome b (Cyt b). DNA sequences from the L. verrucarum series (L. columbiana, L. evansi and L. ovallesi) were used as outgroups. Flies from two locations on the western cordillera of the Andes were identified as L. townsendi s.s., according to male morphology and distinctive gene lineages. In the third location, on the central cordillera of the Andes, most specimens were identified as belonging to a geographical population of L. youngi, according to male morphology, an EF-alpha lineage shared with L. youngi from the Venezuelan-type locality, and a distinctive Cyt b sub-lineage. All other specimens were identified as L. youngi with the introgressed Cyt b sequences of L. townsendi. Such interspecific introgression implies that vectorial traits and ecological associations may no longer be viewed as fixed properties of different morphospecies.     

Parallel Cascade Recognition of Exon and Intron DNA Sequences

Many of the current procedures for detecting coding regions on human DNA sequences combine a number of individual techniques such as discriminant analysis and neural net methods. Recent papers have used techniques from nonlinear systems identification, in particular, parallel cascade identification (PCI), as one means for classifying protein sequences into their structure/function groups. In the present paper, PCI is used in a pilot study to distinguish exon (coding) from intron (noncoding; interspersed within genes) human DNA sequences. Only the first exon and first intron sequences with known boundaries in genomic DNA from the T-cell receptor locus were used for training. Then, the parallel cascade classifiers were able to achieve classification rates of about 89% on novel sequences in a test set, and averaged about 82% when results of a blind test were included. In testing over a much wider range of human nucleotide sequences, PCI classifiers averaged 83.6% correct classifications. These results indicate that parallel cascade classifiers may be useful components in future coding region detection programs. © 2002 Biomedical Engineering Society. PAC2002: 8715Cc, 8714Gg, 8715Aa