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Restriction site mapping of chloroplast DNA from 31 species representing 26 genera of theRanunculaceae was performed using eleven restriction endonucleases. The chloroplast genome varies in length from approximately 152 to 160 kb. Length variants are frequent in theRanunculaceae and range from usually less than 300 bp to rarely 1.5 kb. The inverted repeat is extended into the large single copy (LSC) region by 4–4.5 kb inAnemone, Clematis, Clematopsis, Hepatica, Knowltonia, andPulsatilla. Several inversions are present in the LSC-region of the cpDNA in all these genera and inAdonis. The frequency of restriction site mutations varies within the chloroplast genome in theRanunculaceae between 4 and 32 mutations per kilobase, and is lowest in the inverted repeat and the regions containing the ATPase-genes and the genespsaA, psaB, psbA, rpoB, andrbcL. A total of 547 phylogenetically informative restriction sites was utilized in cladistic analyses of the family using Wagner, Dollo, and weighted parsimony. These three parsimony analyses result in different tree topologies. Four, six, and one equally most parsimonious trees were obtained with Wagner, Dollo, and weighted parsimony, respectively. The amount of support for the monophyletic groups was evaluated using bootstrapping and decay analysis. All three parsimony methods suggest thatHydrastis is the sister group to the remainder of theRanunculaceae, and that theAnemone-Clematis group, which shares several derived cpDNA rearrangements, is monophyletic. Only a few of the traditional groups in theRanunculaceae are supported by cpDNA restriction side data. Only Dollo parsimony provides support for the hypothesis thatThalictroideae andRanunculoideae are monophyletic.  相似文献   
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The yeast Snf1, animal AMPK, and plant SnRK1 protein kinases constitute a family of related proteins that have been proposed to serve as metabolic sensors of the eukaryotic cell. We have previously reported the characterization of two redundant SnRK1 encoding genes (PpSNF1a and PpSNF1b) in the moss Physcomitrella patens. Phenotypic analysis of the snf1a snf1b double knockout mutant suggested that SnRK1 is important for the plant’s ability to recognize and adapt to conditions of limited energy supply, and also suggested a possible role of SnRK1 in the control of plant development. We have now used a yeast two-hybrid system to screen for PpSnf1a interacting proteins. Two new moss genes were found, PpSKI1 and PpSKI2, which encode highly similar proteins with homologues in vascular plants. Fusions of the two encoded proteins to the green fluorescent protein localize to the nucleus. Knockout mutants for either gene have an excess of gametophores under low light conditions, and exhibit reduced gametophore stem lengths. Possible functions of the new proteins and their connection to the SnRK1 kinase are discussed.  相似文献   
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The present study elucidates the possibilities to diagnose and classify urothelial tumors of the upper urinary tract by means of exfoliative cytology on voided urine using a membrane filter method. In a series of 30 patients with renal pelvic tumors and 13 patients with ureteral tumors an overall agreement between cytology and histopathology was obtained in 25 cases (58%). None of the Grade 1 tumors or of the non-invasive Grade 2 tumors were regarded as positive by cytology whilst two out of five invasive Grade 2 tumors had positive cytologic reports. The series included 24 patients with poorly differentiated or anaplastic tumors, 17 of whom had positive cytology (71%). By excluding from the series 13 patients with obstructed urinary passages or radiologically non-functioning kidneys on the tumor side an agreement between cytology and pathology was reached in 83 per cent of the cases, regardless of tumor grade, and in 17 out of 18 patients with Grade 3-4 tumors (94%).  相似文献   
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Summary A partial alcohol dehydrogenase, ADH I, deficient mutant, GRF 18-2 of S. cerevisiae has been isolated. The mutant is resistant to allyl alcohol and the spec. activity of ADH I is 15-fold reduced in the mutant. In a batch fermentation the mutant overproduces glycerol. The production is enhanced 6–7 fold compared with the wildtype strain and it amounts to about 40 per cent of the ethanol produced. The yield of ethanol and glycerol is 56 and 24 per cent respectively. Another mutant possibly defect in the gene for ADH II has a reduced capacity to oxidize ethanol.  相似文献   
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Research Notes on Avian Biology 1994: Selected Contributions from the 21st International Ornithological CongressMorphology and Physiology: Orientation

Subject: Navigation and orientation  相似文献   
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We investigated a polyethylene glycol non-precipitable low-density lipoprotein (LDL) subfraction targeted by IgG and the influence of statin therapy on plasma levels of these small LDL-IgG-immune complexes (LDL-IgG-IC). LDL-subfractions were isolated from 6 atherosclerotic subjects and 3 healthy individuals utilizing iodixanol density gradient ultracentrifugation. Cholesterol, apoB and malondialdehyde (MDA) levels were determined in each fraction by enzymatic testing, dissociation-enhanced lanthanide fluorescence immunoassay and high-performance liquid chromatography, respectively. The levels of LDL-IgG-IC were quantified densitometrically following lipid electrophoresis, particle size distribution was assessed with dynamic light scattering and size exclusion chromatography. The influence of simvastatin (40 mg/day for three months) on small LDL-IgG-IC levels and their distribution among LDL-subfractions (salt gradient separation) were investigated in 11 patients with confirmed coronary artery disease (CAD). We demonstrate that the investigated LDL-IgG-IC are small particles present in atherosclerotic patients and healthy subjects. In vitro assembly of LDL-IgG-IC resulted in particle density shifts indicating a composition of one single molecule of IgG per LDL particle. Normalization on cholesterol levels revealed MDA values twice as high for LDL-subfractions rich in small LDL-IgG-IC if compared to dominant LDL-subfractions. Reactivity of affinity purified small LDL-IgG-IC to monoclonal antibody OB/04 indicates a high degree of modified apoB and oxidative modification. Simvastatin therapy studied in the CAD patients significantly lowered LDL levels and to an even higher extent, small LDL-IgG-IC levels without affecting their distribution. In conclusion simvastatin lowers levels of small LDL-IgG-IC more effectively than LDL-cholesterol and LDL-apoB levels in atherosclerotic patients. This antiatherogenic effect may additionally contribute to the known beneficial effects of this drug in the treatment of atherosclerosis.  相似文献   
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Genetics of the quantitative Lp(a) lipoprotein trait   总被引:12,自引:1,他引:12  
The Lp(a) lipoprotein is a complex particle composed of a low density lipoprotein (LDL)-like lipoprotein and the disulfide bonded Lp(a) glycoprotein. The complex represents a quantitative genetic trait. SDS gel electrophoresis under reducing conditions of sera followed by immunoblotting with affinity-purified polyclonal anti-Lp(a) demonstrated inter- and intra-individual size heterogeneity of the glycoprotein with apparent Mr in the range 400-700kDa. According to their relative mobilities compared to apo B-100 the Lp(a) patterns were categorized into phenotypes F, B, S1, S2, S3 und S4 and into the respective double-band phenotypes. This size heterogeneity seems to be controlled by multiple alleles designated LpF, LpB, LpS1, LpS2, LpS3, LpS4 and a null allele (LpO) at a single locus. Phenotype frequencies observed in 441 unrelated subjects were in good agreement with those expected from the genetic hypothesis. Comparison of Lp(a) lipoprotein concentrations in the different phenotypes revealed a highly significant association of phenotypes B, S1 and S2 with high, and phenotypes S3 und S4 with intermediate Lp(a) concentrations. A third mode is represented by the null phenotype were no Lp(a) band is detected upon immunoblotting and Lp(a) lipoprotein is low or absent. We conclude that the same gene locus is involved in determining Lp(a) glycoprotein phenotype and Lp(a) lipoprotein concentrations in plasma. This major gene seems to be the Lp(a) glycoprotein structural gene locus.  相似文献   
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