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211.
One new species of Sphaeroplea (S. bourrellyii Islam), and six taxa, hitherto unrecorded from Iraq, namely, Dichotomosiphon tuberosus (A. Br.) Ernst, Johannesbaptistia pellucida (Dickie) Taylor & Drouet, Microcoleus chthonoplastes Thuret ex Gomont, M. lacustris (Rab.) Farlow, Gloeotrichia longiarticulata G. S. West, and Ammatoidea (?) normanni W. & G. S. West are described and illustrated.  相似文献   
212.
In this study we have mapped newly identified rDNA loci in Gossypium hirsutum. Four new minor 18S-26S rDNA loci, in addition to the sites previously identified, were mapped using fluorescence in situ hybridization (FISH) to heterozygous translocation (NT) quadrivalents (IVs). The newly detected 18S-26S rDNA loci were mapped to the right arms of chromosomes 8, 9, 15, 17, 19, 20, and 23 and the left arms of chromosomes 5, 11, 12, and 14. Using the rDNA loci as common reference points, we detected several erroneous arm assignments in the previously published map of NT breakpoints. The data are summarized in the form of an integrated map for all 17 known rDNA loci, relative to centromeres, telomeres, and NT breakpoints. This information will facilitate future locus-specific research on rRNA gene evolution and function. Received: 26 January 1998; in revised form: 28 May 1998 / Accepted: 12 February 1999  相似文献   
213.
A total of 55 taxa belonging to Trachelomonas (Euglenophyta) are reported from Bangladesh. Of these, 5 varieties (Tr. allorgei var. madaripurense, Tr. anguste-ovata var. ellipsoidea, Tr. armata var. rangpurense, Tr. hispida var. subcoronata, Tr. asymmetrica var. crenulata) and one forma (Tr. anguste-ovata fa. minor) are described as new to science.  相似文献   
214.
Eight species of Vaucheria from southern Iraq, V. dichotoma, V. sessilis, V. erythrospora, V. verticillata, V. hamata, V. woroniniana, V. synandra, and V. longicaulis were studied and described. All but V. sessilis and V. longicaulis are recorded for the first time from Iraq.  相似文献   
215.
Distinct substructures within the nucleus are associated with a wide variety of important nuclear processes.Structures such as chromatin and nuclear pores have specific roles,while others such as Cajal bodies are more functionally varied.Understanding the roles of these membraneless intra-nuclear compartments requires extensive data sets covering nuclear and compartment-associated proteins.NSort/DB is a database providing access to intra-or sub-nuclear compartment associations for the mouse nuclear proteome.Based on resources ranging from large-scale curated data sets to detailed experiments,this data set provides a high-quality set of annotations of non-exclusive association of nuclear proteins with structures such as promyelocytic leukaemia bodies and chromatin.The database is searchable by protein identifier or compartment,and has a documented web service API.The search interface,web service and data download are all freely available online at http://www.nsort.org/db/.Availability of this data set will enable systematic analyses of the protein complements of nuclear compartments,improving our understanding of the diverse functional repertoire of these structures.  相似文献   
216.
Thermolysin was stabilized by increasing the reaction temperature from 90°C to 110°C during peptide synthesis of N-(benzyloxycarbonyl)-L-phenylalanyl-L-phenylalanine methyl ester (Z-Phe-Phe-OMe). The stabilization energy was acquired from the drop in both pH and dielectric constant due to the temperature increase. The acquired stabilization energy was as high as ca. 42 kJ/mol (corresponding to 20°C). This acquired stabilization energy did not result from a single event such as a change in electrical charges. It was evaluated as the overall stabilization energy at and around the active site area of the enzyme using an electrostatic potential equation.  相似文献   
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