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41.
Polymorphism of the ABO blood group gene was investigated in 262 healthy Japanese donors by a polymerase chain reactions-single-strand conformation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A1 (provisionally called ABO*A101, *A102, *A103 and *A104 according to the guidelines for human gene nomenclature), 3 for B (ABO*B101, *B102 and *B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O203). Nucleotide sequences of the amplified fragments with different SSCP patterns were determined by direct sequencing. Phylogenetic network analysis revealed that these alleles could be classified into three major lineages, *A/*O1, *B and *O2. In Japanese, *A102 and *13101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, *O101 (43%) and *O201 (53%), were observed. These results may be useful for the establishment of ABO genotyping, and these newly described ABO alleles would be advantageous indicators for population studies.  相似文献   
42.
Abstract Microcystis aeruginosa (Synechocystis ) is a unicellular cyanobacterium that performs oxygenic photosynthesis. We found two novel sets of repetitive sequences, A (REP-A) and B (REP-B), on the M. aeruginosa K-81 genomic DNA, which consisted of distinct motifs of tandem repeated sequences located in the up- and downstream regions of the orf1 structural gene, respectively. Genomic Southern hybridization revealed multicopies of REP-A and -B on the genome. Furthermore, genomic Southern blots of cyanobacteria species with the REP-A and -B probes revealed that different hybridization signals appeared on the genomic DNAs of all 12 Microcystis strains, but no signal appeared on those of Synechocystis sp. PCC 6803, Synechococcus sp. PCC 7942, and Anabaena sp. PCC 7120.  相似文献   
43.
The vertical distribution and feeding of pelagic chaetognathsat 5°S, 160°W in the Central Equatorial Pacific wereinvestigated using a series of 0–500 m vertical haulswith a VMPS net over a 24 h period between 6 and 7 October 1990.The total number of individuals per haul was between 370 and688. Fourteen species in four genera were found at this station.The most abundant species was Sagitta enflata which comprised32.4–61.1% of the individuals collected from the 0–500m layer. Mesopelagic species made up 9.3–15.1% of thetotal number of individuals. Sagitta enflata and Pterosagittadraco were found in the upper part of the thermocline both byday and at night. The fraction of the population containingfood items (FCF) of S.enflata in the 0–50 m layer variedbetween 4.8 and 12.5% (mean 10.8%) and feeding activity washighest between sunrise and noon. The percentages of Copepoda,Foraminifera, crustacean larvae, Chaetognatha, Pteropoda, Ostracoda,fish and unidentified material in the gut of S.enflata were51.9,6.7,3.8,2.9,1.9,1.9 and 30.9%, respectively. Sagitta enflataconsumed food organisms which were mainly between 0.5 and 1.0mm in length. The daily feeding rate of S.enflata was 1.81 preyper individual, which was equivalent to 8.06 mg C m–2day–1. This corresponded to  相似文献   
44.
The effects of allyl, sulfur and cyanogenic compounds on thegermination of upper cocklebur (Xanthium pennsylvanicum Wallr.)seeds were examined. Mercaptoethanol and methylmercaptan aswell as KCN, substrates for rßcyanoalanine synthase(CAS), and H2S and thiocyanate, the products of the CAS catalyzingreaction, were effective in promoting germination, suggestingthe involvement of CAS in germination. Most of allyl compounds, especially allylthiourea, as well asethylene which activated CAS [Hasegawa et al. (1994) Physiol.Plant. 91: 141], promoted the germination in an abnormal typewhich occurred by the predominant growth of cotyledons as didC2H4 [Katoh and Esashi (1975) Plant Cell Physiol. 16: 687].However, they failed to activate CAS unlike ethylene, and toliberate free ethylene during an incubation period. It was thuspossible that an C2H4-like double bond within allyl compoundscan act to promote seed germination. (Received June 10, 1996; Accepted August 21, 1996)  相似文献   
45.
Bacillus subtilis YB8 was found to produce the lipopeptide antibiotics surfactin and plipastatin B1. A gene, lpa-8, required for the production of both lipopeptides was cloned from strain YB8. When this gene was inactivated in strain YB8, neither surfactin nor plipastatin B1 was produced. However, the defective strain transformed with an intact lpa-8 gene had restored ability to produce both peptides. Nucleotide sequence analysis of the region essential for the production of the peptides revealed the presence of a large open reading frame. The deduced amino acid sequence of lpa-8 (224 amino acid residues) showed sequence similarity to that of sfp (from surfactin-producing B. subtilis), lpa-14 (from iturin A- and surfactin-producing B. subtilis), psf-1 (from surfactin-producing Bacillus pumilus), gsp (from gramicidin-S-producing Bacillus brevis), and entD (from siderophore-enterobactin-producing Escherichia coli), which are able to complement a defect in the sfp gene and promote production of the lipopeptide antibiotic surfactin. The sequence similarity among these proteins and the product similarity of cyclic peptides suggests that they might be involved in the biosynthesis or secretion of the peptides. Received: 14 July 1995 / Accepted: 22 December 1995  相似文献   
46.
Pollination biology of 41 plants species of 21 families blooming in the forest understory was investigated in a lowland mixed diplerocarp forest in Lambir Hills National Park, Sarawak. Among these species, 29 species (71%) were pollinated by bees, four (10%) by nectariniid birds, three by small dipterans, and others by moths, butterflies, syrphid flies, wasps, and beetles. The 29 bee-pollinated species consisted of five distinct pollination guilds: ten species pollinated by medium traplining bees (two Amegilla species), nine by small traplining bees (three halictid and a xylocopine species), two by stingless bees and beetles, seven by stingless bees, and one by megachilid bees. The bees constituting the first two guilds were shade-loving, swiftly flying, long-tongued trapliners. Proboscis lengths of these pollinators correlated with flower depth of the host plant. Pollination systems in the forest understory were distinguished from that in the canopy by the prevalence of specific interactions, the number of traplining solitary bees, and lack of pollination systems by mass-recruiting eusocial bees, large Xylocopa bees, thrips, bats, and wind. These characteristics are largely similar between the Palaeotropics and the Neotropics through convergence of nectarivorous birds (spiderhunters vs. hummingbirds) and traplining bees (Amegilla vs. euglossine bees).  相似文献   
47.
48.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.  相似文献   
49.
Nocturnal flying insects were collected monthly for 13 months using ultra violet light-traps set at various vertical levels in a weakly-seasonal, tropical lowland dipterocarp forest in Sarawak, Malaysia. Abundance, faunal composition, size distribution and guild structure of these samples were analyzed with respect to temperal and vertical distributions. The nocturnal flying insect community in the canopy level was highly dominated by fig wasps (84%) in individual number, and by scarabaeid beetles (28%) in weight. A principal component analysis on monthly catches detected non-random, seasonal trends of insect abundance. The first two principal trends were an alternation of wetter (September to January) and less wet seasons (February to August) and an alternation between the least wet (January to March) and the other seasons. Many insect groups were less abundant in the least wet season than the other seasons, whilst inverse patterns were found in Scarabaeidae and Tenebrionidae. Significantly positive and negative correlations between monthly catch and rainfall were detected only in ovule-feeders and in phloem-feeders, respectively. Delayed, significant negative correlations between monthly catch and 1–3 month preceding rainfall were more frequently detected in phytophages, phloem-feeders, seed-feeders, wood-borers and scavengers. The peak in abundance along vertical levels were found at the canopy level (35 m) for phloem-, ovule-, seed-, root-, fungal-feeders and nectar collectors, at an upper subcanopy level (25 m) for scavengers and aquatic predators, and at a middle subcanopy level (17 m) for ants. Catches at the emergent level (45 m) did not exceed those at the canopy level.  相似文献   
50.
The surface coat, ciliary process, and microvilli of the lamprey neuromast were examined with electron microscopy after tannic acid prefixation and lectin histochemistry. The neuromast was found to exist in the form of a dermal mound with a furrow in the middle. On the bottom of the furrow, the hair cell was characterized by a kinocilium and 15–20 stereocilia, arranged along the longitudinal axis of the furrow. Spanning structures were demonstrated between the kinocilium and stereocilia as well as between stereocilia. The surface coat, enhanced by tannic acid prefixation, was particularly rich over the surface of the supporting cell; by contrast, it was thin over the hair cell. Some lectins (PNA, GS-I, SBA, WGA) showed affinity to the surface coat of the supporting cell as well as the hair cell, and the others (RCA-I, MPA, ConA) showed affinity only to the supporting cell. These differences in the structure and affinities of the surface coat suggest an extracellular milieu highly specialized for the hair cell in this particular form of the mechanoreceptor.  相似文献   
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