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MOTIVATION: Numerous database management systems have been developed for processing various taxonomic data bases on biological classification or phylogenetic information. In this paper, we present an integrated system to deal with interacting classifications and phylogenies concerning particular taxonomic groups. RESULTS: An information-theoretic view (taxon view) has been applied to capture taxonomic concepts as taxonomic data entities. A data model which is suitable for supporting semantically interacting dynamic views of hierarchic classifications and a query method for interacting classifications have been developed. The concept of taxonomic view and the data model can also be expanded to carry phylogenetic information in phylogenetic trees. We have designed a prototype taxonomic database system called HICLAS (HIerarchical CLAssification System) based on the concept of taxon view, and the data models and query methods have been designed and implemented. This system can be effectively used in the taxonomic revisionary process, especially when databases are being constructed by specialists in particular groups, and the system can be used to compare classifications and phylogenetic trees. AVAILABILITY: Freely available at the WWW URL: http://aims.cps.msu.edu/hiclas/ CONTACT: pramanik@cps.msu.edu; lotus@wipm.whcnc.ac.cn 相似文献
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Imai R Ali A Pramanik HR Nakaminami K Sentoku N Kato H 《Journal of plant physiology》2004,161(7):883-886
A cDNA for a putative 42 kD spermidine synthase (OsSPDS2) was cloned from rice. The deduced OsSPDS2 sequence showed highest similarity with Arabidopsis AtSPDS3. Phylogenetic analysis revealed that OsSPDS2 and AtSPDS3 form a distinctive subclass in the spermidine synthase family in plants. OsSPDS2 mRNA accumulated in roots during long term exposure to chilling temperature (12 degrees C). In contrast, no such induction of the paralogous OsSPDS1 was observed during the chilling treatment. ABA treatment up-regulated OsSPDS2, whereas salt stress did not change OsSPDS2 levels significantly. Data suggested a distinct function of OsSPDS2 in chilling response in rice. 相似文献
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Boyadjiev SA Justice CM Eyaid W McKusick VA Lachman RS Chowdry AB Jabak M Zwaan J Wilson AF Jabs EW 《Human genetics》2003,113(1):1-9
We describe a new dysmorphic syndrome in an inbred Saudi Arabian family with 21 members. Five males and one female have similar craniofacial features including wide open calvarial sutures with large and late-closing anterior fontanels, frontal bossing, hyperpigmentation with capillary hemangioma of the forehead, significant hypertelorism, and a broad and prominent nose. In addition, these individuals have Y-shaped sutural cataracts diagnosed by 1-2 years of age. No chromosomal or biochemical abnormalities were identified. A genome-wide scan was performed, and two-point LOD score analysis, assuming autosomal recessive inheritance, detected linkage to chromosome 14q13-q21. The highest LOD scores were obtained for marker GATA136A04 (LOD=4.58 at theta=0.00) and for the adjacent telomeric marker D14S1048 (LOD=4.32 at theta=0.00). Multipoint linkage analysis resulted in a maximum LOD score of 5.44 between markers D14S1048 and GATA136A04. Model independent analysis by SIBPAL confirmed linkage to the same chromosomal region. Haplotype analysis indicated that all affected individuals were homozygous for the interval on chromosome 14q13-q21 with two recombinants for D14S1014 (centromeric) and one recombinant for D14S301 (telomeric). These recombinations limit the disease locus to a region of approximately 7.26 Mb. Candidate genes localized to this region were identified, and analysis of PAX9 did not identify mutations in these patients. The unique clinical phenotype and the mapping data suggest that this family represents a novel autosomal recessive syndrome. 相似文献
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Glucose oxidase (GOD) from Aspergillus niger was expressed in Saccharomyces cerevisiae under the regime of GAL-10 promoter and GAL-7 terminator of S. cerevisiae and -amylase signal sequence of Aspergillus oryzae. The enhancement of the expression level was achieved in pH-stat feed-back controlled fed-batch culture. The highest titre of extracellular GOD was 199 U/ml which marked two fold improvement over the batch (95 U/ml) and 28% above that of non-feed back controlled fed-batch (154 U/ml) operation. © Rapid Science Ltd. 1998 相似文献
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Development and evaluation of a multiplex PCR assay for rapid detection of toxigenic Vibrio cholerae O1 and O139 总被引:7,自引:0,他引:7