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11.
A DNA fragment containing the genes for the eight ribosomal proteins HmaL3, HL6, HmaL23, HmaL2, HmaS19, HmaL22, HmaS3, and HmaL29 from Halobacterium marismortui has been cloned and sequenced. The organization of this gene cluster in general corresponds to the S10 operon of Escherichia coli although there exists some differences between them. The sequence analysis of the 5'- and 3'-region of the gene cluster revealed three open reading frames (orf1, orf2, and orf3) which do not code for any ribosomal protein whose structure is known. A putative promoter is located upstream of orf1. Out of the eight ribosomal proteins five have counterparts in eubacteria only, two in both eubacteria and eukaryotes, and one is exclusively related to an eukaryotic ribosomal protein.  相似文献   
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Postrhinoplasty "red nose": differential diagnosis and treatment by laser   总被引:1,自引:0,他引:1  
Prior to anticipated nasal surgery, the nasal and facial skin should be examined for any vascular lesions. The skin type should be ascertained. A history of any prior nasal surgery, particularly on the nasal dorsum, should be noted. If rosacea is a clinical possibility, a trial of 1.5 to 2.0 gm q.d. of tetracycline for 6 to 8 weeks is warranted. If, after rhinoplasty, a diffuse "redness" on the nasal dorsum results and one can exclude other diagnoses, then argon laser therapy should be considered. A 3-mm punch biopsy should be obtained to see whether superficial ectatic vessels are present, a finding that would be indicative of a good result from laser therapy.  相似文献   
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Synopsis The aim of this paper is the selective visualization of human blood basophils in autoradiographs. [3H]Thymidine-labelled basophils in buffy coat smears were fixed in methanol-formaldehyde followed by 5-aminoacridine hydrochloride and stained with basic Aldehyde Fuchsin prior to autoradiographic processing. The technique described represents a simple method for quantitative autoradiographic studies on basophil kinetics and the interaction of these cells with IgE-mediated atopias.  相似文献   
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The effect of the thermal fluctuation on the orientation distribution pattern of globular protein molecules in a two-dimensional lattice was investigated by the method of computer simulation. A set of interaction parameters was assigned to interaction sites on each molecule and the interaction energy between two molecules was given by the product of the parameters of facing sites. Orientation fluctuation was assumed to take place with the probability proportional to the Boltzmann factor. Patterns having different degrees of order appeared with the change of temperature. The entropy and other thermodynamic quantities of these patterns were calculated, and gradual and transitional changes of the pattern were discussed in comparison with the case of simple atoms or molecules.  相似文献   
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Identification of single nucleotide polymorphisms (SNPs) is a key element in sequence-based genetic analysis. Next generation sequencing offers a cost-effective basis to generate the necessary, large sequence data sets, and bioinformatic methods are being developed to process sequencing machine readouts. We were interested in detection of SNPs in a 350 kb region of an EMS-mutagenized Arabidopsis chromosome 3. The region was selectively analyzed using PCR-generated, overlapping fragments for Solexa sequencing. The ensuing reads provided a high coverage and were processed bioinformatically. In order to assess the SNP candidates obtained with a frequently used alignment program and SNP caller, we developed an additional method that allows the identification of high confidence SNP loci. The method can easily be applied to complete genome sequence data of sufficient coverage.  相似文献   
20.

Background and aims

Green roofs are often installed to reduce urban stormwater runoff. To optimally achieve this, green roof plants need to use water when available, but reduce transpiration when limited to ensure survival. Succulent species commonly planted on green roofs do not achieve this. Water availability on green roofs is analogous to natural shallow-soil habitats including rock outcrops. We aimed to determine whether granite outcrop species could improve green roof performance by evaluating water use strategies under contrasting water availability.

Methods

Physiological and morphological responses of 12 granite outcrop species with different life-forms (monocots, herbs and shrubs) and a common green roof succulent were compared in well watered (WW) and water deficit (WD) treatments.

Key results

Granite outcrop species showed a variety of water-use strategies. Unlike the green roof succulent all of the granite outcrop species showed plasticity in water use. Monocot and herb species showed high water use under WW but also high water status under WD. This was achieved by large reductions in transpiration under WD. Maintenance of water status was also related to high root mass fraction.

Conclusions

By developing a conceptual model using physiological traits we were able to select species suitable for green roofs. The ideal species for green roofs were high water users which were also drought tolerant.  相似文献   
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