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1.
To clarify the feeding habits of seagrass fishes, the gut contents of 31 fish species collected in aZostera marina bed at Aburatsubo central Japan, were examined. Ontogenetic changes in food preference were recognized in 12 species. In
general, juveniles of the latter preyed mainly on small crustaceans (e.g., gammaridean amphipods) or planktonic animals (e.g.,
calanoid and cyclopoid copepods), subsequently changing to other prey items (e.g., hard-shelled animals) with growth. Cluster
analysis based on dietary overlaps showed that the seagrass fish assemblage comprised seven feeding guilds (small-crustacean,
planktonic-animal, large-crustacean, polychaete, fish, hard-shelled mollusc and detritus feeders). Of these, small-crustacean
feeders and planktonic-animal feeders were the most abundantly represented, including juveniles of several species, which,
when adult, transferred to other feeding guilds. On the other hand detritivores were represented by a single species. 相似文献
2.
3.
4.
A new marking technique for live fish eggs and larvae was proposed to elucidate the larval biology and adult breeding ecology
of wild fish. In the laboratory, females of a freshwater goby Rhinogobius sp. OR were abdominally injected with one of three coloring agents—brilliant blue FCF, rose Bengal, or β-carotene—before
their oviposition. The rose Bengal proved lethal to adult fish. The other two dyes had little effect on adult mortality. With
these two treatments, there were negative effects on neither fecundity nor egg mortality, resulting in normally developed
larvae. The brilliant blue FCF stained eggs and larvae greenish blue whereas the staining effect of β-carotene was unclear.
The timing of injection was important in effective staining of eggs and reducing the risk of miscarriage. In conclusion, the
brilliant blue FCF was the more useful marker. We discuss what this method can show us about the ecology of wild fish and
how this method can be applied to field study.
Received: March 6, 2002 / Revised: July 11, 2002 / Accepted: August 14, 2002
RID="*"
ID="*" Present address: Center for Marine Environmental Studies, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577, Japan
(e-mail: nokuda@sci.ehime-u.ac.jp)
Acknowledgments I am grateful to K. Karino, M. Kohda, and A. Moriyama for giving us valuable advice and to M. Inoue and H. Miyatake for their
field assistance. This study was financially supported by Research Fellowships of the Japan Society for the Promotion of Science
for Young Scientists.
Correspondence to:Noboru Okuda 相似文献
5.
Summary. Asymmetric synthesis of all four stereoisomers of 6-methylpipecolic acids with high enantiomeric purity via iterative AD
reaction, starting from 1,6-heptadiene, has been described.
Received March 25, 2002 Accepted June 15, 2002 Published online January 30, 2003
Authors' address: Hiroki Takahata, Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan, E-mail: takahata@tohoku-pharm.ac.jp
RID="*"
ID="*" The stereo-configurations of 8 and 9 in Fig. 3 and 12 in Fig. 4 show only major isomers.
RID="**"
ID="**" The absolute configurations of 11 and 14 相似文献
6.
Female spawning strategy in Rhinogobius sp. OR: how do females deposit their eggs in the nest? 总被引:1,自引:1,他引:0
We tried to elucidate how females of a paternal nest brooding goby Rhinogohius sp. OR deposit their eggs in a nest, using a marking technique for live eggs under laboratory conditions in which male somatic
condition, nest space, and mating pattern (monogamous or bigamous) were controlled. Whether females rejected mating was independent
of either male quality, such as body size and somatic condition, or nest space. In a situation in which two females were allowed
to spawn sequentially with a male, however, females rejected mating at a higher rate when they were the first to spawn than
when they were the second to spawn; this is because eggs from first females were more vulnerable to cannibalism by parental
males and second females. Even when nest space was limited and thus was occupied by eggs from the first females, second females
could deposit all their eggs in the nest by using the minute interspace of existing eggs. In the presence of the parental
male, such a female seemed less likely to suffer a cost from increased egg mortality due to crowdedness, still holding the
advantage of being the second spawner. Finally, we extrapolated the field breeding ecology of this fish from the laboratory
data. It was suggested that a single monolayer brood of the same age usually consisted of eggs from multiple females and thus
the mating pattern would be more polygynous than previously expected.
Received: March 6, 2002 / Revised: July 11, 2002 / Accepted: August 14, 2002
RID="*"
ID="*" Present address: Center for Marine Environmental Studies, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577, Japan
(e-mail: nokuda@sci.ehime-u.ac.jp)
Acknowledgments I am grateful to S. Sone and D. Takahashi for giving us useful information and to M. Inoue and H. Miyatake for their field
assistance. This study was financially supported by Research Fellowships of the Japan Society for the Promotion of Science
for Young Scientists.
Correspondence to:Noboru Okuda 相似文献
7.
We establish the existence of traveling front solutions and small amplitude traveling wave train solutions for a reaction-diffusion
system based on a predator-prey model with Holling type-II functional response. The traveling front solutions are equivalent
to heteroclinic orbits in R
4
and the small amplitude traveling wave train solutions are equivalent to small amplitude periodic orbits in R
4
. The methods used to prove the results are the shooting argument and the Hopf bifurcation theorem.
Received: 25 May 2001 / Revised version: 5 August 2002 / Published online: 19 November 2002
RID="*"
ID="*" Research was supported by the National Natural Science Foundations (NNSF) of China.
RID="*"
ID="*" Research was partially supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada. On leave
from the Department of Mathematics and Statistics, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada.
Mathematics Subject Classification (2000): 34C35, 35K57
Key words or phrases: Traveling wave solution – Wazewski set – Shooting argument – Hopf bifurcation
Acknowledgements. We would like to thank the two referees for their careful reading and helpful comments. 相似文献
8.
Summary. 10 nm diameter filaments were observed in whole-mount preparations of algae of diverse phyla: Acetabularia acetabulum and A. major (Chlorophyta), Chara australis and Nitella flexilis (Charophyta), and Poterioochromonas malhamensis (Chrysophyta). A polyclonal antibody raised against a basic, 50 kDa DNA-binding protein of A. acetabulum stains the filaments of A. acetabulum and A. major as well as of C. australis and N. flexilis. While in the perinuclear region of A. acetabulum and A. major and throughout the cytoplasm of P. malhamensis the 10 nm filaments have a smooth appearance, in the stalk of A. acetabulum and A. major they are densely covered by globular structures; in C. australis and N. flexilis they are less frequently associated with such material. The morphology of a part of the globular particles is quite reminiscent
of prosomes. A monoclonal antibody elicited against prosomes isolated from A. acetabulum indeed decorates the globular particles on the A. acetabulum and A. major filaments. The possible role of these filament-particle associations is discussed.
Received August 10, 2001; accepted October 30, 2002; published online April 8, 2003
RID="*"
ID="*" Correspondence and reprints: Max-Planck-Institut für Zellbiologie, 68526 Ladenburg, Federal Republic of Germany. E-mail:
sberger@zellbio.mpg.de
RID="**"
ID="**" Present address: Long Island University, Southampton, New York, U.S.A.
RID="+"
ID="+" Present address: Leica Microsystems Wetzlar GmbH, Wetzlar, Federal Republic of Germany 相似文献
9.
Summary. The non-Mendelian inheritance of organelle DNA is common in most plants and animals. Here we examined inheritance mechanisms
involved in the transfer of mitochondrial DNA. We successively backcrossed (to F5) two interfertile strains of the unicellular isogamous haploid algae Chlamydomonas reinhardtii and Chlamydomonas smithii to match nuclear backgrounds and examine transmission patterns of mitochondrial DNA by PCR analysis of cob gene sequences. Mitochondrial DNA was strictly transmitted paternally. To investigate the behavior of parental mitochondrial
DNA, we used F5 progeny to form zygotes and isolated single zygotes. The results showed selective disappearance of maternal mitochondrial
nucleoids occurred between 3 and 6 h after zygote formation.
Received July 11, 2002; accepted September 28, 2002; published online June 13, 2003
RID="*"
ID="*" Correspondence and reprints: Laboratory of Cell and Functional Biology, Faculty of Science, University of the Ryukyus,
Nishihara, Okinawa 903-0213, Japan. 相似文献
10.
Summary. Sphingomyelin is an abundant constituent of the plasma membranes of mammalian cells. Ceramide, its primary catabolic intermediate,
has emerged as an important lipid signaling molecule. Previous work carried out by our group has documented that plasma membrane
Mg2+-dependent neutral sphingomyelinase can be effectively inhibited by exogenous ubiquinol. In this work, we have tested whether
or not plasma-membrane-associated electron transport can also achieve this inhibition through endogenous ubiquinol. Our results
have shown that Mg2+-dependent neutral sphingomyelinase in isolated plasma membranes was inhibited by NAD(P)H under conditions where ubiquinone
is reduced to ubiquinol. This inhibition was potentiated in the presence of an extra amount of NAD(P)H:(quinone acceptor)
oxidoreductase 1 (EC 1.6.99.2). Depletion of plasma membranes from lipophilic antioxidants by solvent extraction abolished
the inhibition by reduced pyridine nucleotides without affecting the sensitivity of the neutral sphingomyelinase to exogenous
ubiquinol. Reconstitution of plasma membranes with ubiquinone restored the ability of NAD(P)H to inhibit the enzyme. Our results
support that the reduction of endogenous ubiquinone to ubiquinol by NAD(P)H-driven electron transport may regulate the activity
of the plasma membrane neutral sphingomyelinase.
Received May 20, 2002; accepted September 20, 2002; published online May 21, 2003
RID="**"
ID="**" Present address: Department of Biomedical Engineering, School of Medicine, University of Baltimore, Maryland, U.S.A.
RID="*"
ID="*" Correspondence and reprints: Departamento de Biología Celular, Fisiología e Inmunología, Facultad de Ciencias, Edificio
C-6, Campus Rabanales, Universidad de Córdoba, 14014 Córdoba, Spain. 相似文献
11.
Branched chain amino acids as source of specific branched chain volatile fatty acids during the fermentation process of fish sauce 总被引:6,自引:0,他引:6
Summary. The source of the formation of branched chain volatile fatty acids (VFA) in fish sauce was investigated. Certain branched
VFA were derived from the degradation of specific amino acids as iso-butyric acid from valine and iso-valeric acid from leucine. Short and long straight chain VFA were significantly higher in the linoleic acid added sample
than in the control but did not significantly bring changes to the branched chain VFA. It is suggested that straight chain
VFA developed from fish fats. Alanine and isoleucine did not have a clear influence on the production of volatile fatty acids.
Received November 23, 2001 Accepted June 20, 2002 Published online December 18, 2002
RID="*"
ID="*" Part of this paper was presented in the 7th International Congress on Amino Acids and Proteins in Vienna, Austria from
August 6–10, 2001.
Authors' address: Norlita G. Sanceda, Ph.D., Institute of Environmental Science for Human Life, 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112, Japan,
Fax: + 81-3-5978-5805, E-mail: lita@cc.ocha.ac.jp 相似文献
12.
Yoshie Matsuda Genqing Liang Yali Zhu Fengshan Ma Richard S. Nelson Biao Ding 《Protoplasma》2002,220(1-2):0051-0058
Summary. Previous work has demonstrated that some endogenous plant gene promoters are active in selective companion cells of the phloem,
depending on organ types and developmental stages. Here we report that the Commelina yellow mottle virus (CoYMV) promoter
is active in the companion cells of leaves, stems and roots of transgenic Nicotiana tabacum cv. Xanthi NN, using β-glucuronidase (GUS) as a reporter. Thus, the CoYMV promoter has a broad organ specificity. This promoter
can be useful in molecular studies on the functions of companion cells in many aspects of phloem biology, such as regulation
of long-distance transport, macromolecular traffic, plant development and interaction with pathogens. It may also be useful
in engineering crops that produce specific gene products in the companion cells to block long-distance movement of pathogens.
Received February 5, 2002; accepted March 27, 2002; published online July 4, 2002
RID="*"
ID="*" Correspondence and reprints: Department of Plant Biology and Plant Biotechnology Center, 207 Rightmire Hall, Ohio State
University, 1060 Carmack Road, Columbus, OH 43210, U.S.A. 相似文献
13.
Summary. The 14-residue peptaibol antibiotic trichovirin I 4A of the structure Ac-Aib-L-Asn-L-Leu-Aib-L-Pro-L-Ala-L-Val-Aib-L-Pro-Aib-L-Leu-Aib-L-Pro-L-Leuol
(Aib = α-aminoisobutyric acid, Leuol = leucinol) was synthesized by stepwise conventional solution phase synthesis using the Z/OtBu(OMe) strategy and HOBt/EDC as coupling reagents. Intermediates were fully characterized and the identity of the synthetic
peptide with the component 4A of the natural, microheterogeneous peptide mixture was proven by electrospray mass spectrometry,
HPLC, and bioassay.
Received March 25, 2002 Accepted June 14, 2002 Published online December 18, 2002
RID="*"
ID="*" Dedicated to Prof. Dr. Günther Jung. Tübingen University, on the occasion of his 65th anniversary.
Authors' address: Prof. Dr. Hans Brückner, Interdisciplinary Research Center, Institute of Nutritional Science, Department of Food Sciences,
Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26, D-35392 Giessen, Germany, Fax: +49-641-99-39149, E-mail: hans.brueckner@ernaehrung.uni-giessen.de
Abbreviations: Amino acids are abbreviated according to three-letter-nomenclature; Aib, α-aminoisobutyric acid (2-methylalanine); Iva (isovaline, 2-ethylalanine); Leuol, L-leucinol [(S)-2-amino-4-methyl-1-pentanol]; AAA, amino acid analysis; EI-MS, electron impact mass spectrometry; ESI-MS, electrospray ionization
mass spectrometry; HPLC, high performance liquid chromatography; Z, benzyloxycarbonyl; Fmoc, 9-fluorenylmethyoxycarbonyl;
OtBu, tertiary butoxy (tert-butylester); OMe, methoxy (methyl ester); OBzl, benzyloxy (benzyl ester); TDM, N,N,N′,N′-tetramethyl-4,4′-diamino-diphenylmethane
(Arnold's base); for other abbreviations see Experimental. 相似文献
14.
Takaomi Arai Aya Kotake Madoka Ohji Michael J. Miller Katsumi Tsukamoto Nobuyuki Miyazaki 《Ichthyological Research》2003,50(1):0078-0081
The age and migratory history of the Japanese eel, Anguilla japonica, collected along the Sanriku Coast of Japan, were examined using otolith microstructure and analysis of strontium (Sr) and
calcium (Ca) concentrations. The mean Sr : Ca ratios from the elver mark to the otolith edge indicated that there were eels
with several general categories of migratory history, including sea eels that never entered freshwater and others which had
entered freshwater for brief periods but returned to the estuary or bay. This first evidence of the occurrence of sea eels
in this northern area indicates that Japanese eels of the Sanriku Coast do not necessarily migrate into freshwater rivers.
Received: May 15, 2002 / Revised: August 4, 2002 / Accepted: August 15, 2002
Acknowledgments We thank Messrs. S. Yamane and K. Morita, and crews of the Otsuchi Marine Research Center, Ocean Research Institute, The
University of Tokyo, for their assistance in collecting the eels. This work was supported in part by Grant-in-Aid No. 13760138
from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
Correspondence to:Takaomi Arai 相似文献
15.
Combtooth blennies (Blenniidae) have a wide array of diets, including coral polyps, fish scales/mucus/rays, and detritus. However, there is limited knowledge about the diet of some species. We described the diet of 30 blenny species from subtidal, intertidal, or supralittoral habitats in Kochi (warm temperate) and Okinawa (tropical), Japan. Cluster analysis of dietary overlap grouped blennies into seven feeding groups: omnivores, herbivores, detritivores, molluscivores, corallivores, worm-like invertebrate feeders, and fish mucus/scale/ray feeders. The largest cluster, detritivores, contained 17 blenny species from all habitat zones and both climate zones. Our findings suggest that closely related species fill similar feeding niches and detritus is an important component of many blenny diets. 相似文献
16.
Summary. The NADPH oxidase of neutrophils is a transmembrane electron transfer complex, containing a flavin adenine dinucleotide and
two hemes, all of which are suggested to be contained within gp91
phox
, one of four subunits of the enzyme. The transfer of electrons through the NADPH oxidase is associated with an efflux of
protons. gp91
phox
has previously been demonstrated to function as the proton conduction pathway. The mutation of histidines 111, 115, and 119
to leucines and of histidine 115 to leucine within the N-terminal 230-amino-acid fragment of gp91
phox
has previously been demonstrated to result in the loss of proton conduction through this N-terminal fragment. In this paper
we have investigated the role of these histidines in proton conduction by the full-length gp91
phox
. Stable CHO cell lines were established which expressed full-length gp91
phox
in which histidines 111, 115, and 119 had been mutated to leucines (CHO91H111/115/119) and in which histidine 115 had been
mutated to leucine (CHO91H115L). The expression of gp91
phox
and its cellular localisation in these cell lines were comparable between wild-type and the mutant gp91
phox
. The mutation of histidines 111, 115, and 119 to leucines or just histidine 115 to leucine resulted in an almost total loss
of both the arachidonate-activated influx and efflux of protons, in comparison with that observed for wild-type gp91
phox
. Therefore, histidine 115 is required for proton conduction by both full-length gp91
phox
and the N-terminal 230-amino-acid fragment of gp91
phox
. Histidine 115 has recently been proposed to act as a coordinating ligand for the outer heme iron of the NADPH oxidase. On
the basis of observations for cytochrome c oxidase, we propose a model for this dual role of histidine 115.
Received May 2, 2002; accepted July 26, 2002; published online May 21, 2003
RID="**"
ID="**" Present address: Bristol Institute for Transfusion Sciences, Bristol, United Kingdom.
RID="*"
ID="*" Correspondence and reprints: Department of Biochemistry, School of Medical Sciences, University of Bristol, University
Walk, Bristol BS8 1TD, United Kingdom. 相似文献
17.
Both growth and migratory history of the Pacific Ocean forms of the threespine stickleback Gasterosteus aculeatus collected in Otsuchi Bay, northeastern Japan, were examined using otolith microstructure and analysis of strontium (Sr) and
calcium (Ca) concentrations with wavelength dispersive X-ray spectrometry by an electron microprobe. Age of the juveniles
(21.6–25.9 mm in total length) examined ranged from 101 to 128 days (115 ± 8.5 days; mean ± SD), hatching being estimated
as having occurred between March and April 2001. The Sr : Ca ratios in the otoliths changed with both ontogenic development
and salinity of the habitat. The otolith Sr : Ca ratios increased gradually from 4.1 × 10−3 around the core to 7.5 × 10−3 around the edge of the otolith. The fluctuation pattern of otolith Sr : Ca ratios was different from those observed in both
freshwater resident and anadromous forms in previous studies. These results suggested that the fish sampled spend their lives
in the estuarine and sea environment without freshwater life after hatching.
Received: June 5, 2002 / Revised: September 11, 2002 / Accepted: September 24, 2002
Acknowledgments We thank Mr. K. Morita and crews of the Otsuchi Marine Research Center, Ocean Research Institute, The University of Tokyo
for their assistance in collecting specimens. This work was supported in part by Grant-in-Aid No. 13760138 from the Ministry
of Education, Culture, Sports, Science and Technology, Japan.
Correspondence to:Takaomi Arai 相似文献
18.
A new acropomatid fish, Acropoma
argentistigma, is described on the basis of six specimens (59.0–107.5 mm in standard length) from the Andaman Sea, off southern Thailand
(Phuket Island). The new species is distinguished from all other congeners by the combination of the following characters:
a short U-shaped luminous gland, 16–18 gill rakers, anus situated about midway along depressed pelvic fin, proximal radial
of first anal fin pterygiophore with a trough, a single row of well-developed conical teeth on the lower jaw, and head length
40.0–41.1% of standard length.
Received: April 17, 2001 / Revised: April 15, 2002 / Accepted: May 7, 2002 相似文献
19.
Cytological evidence for preservation of mitochondrial and plastid DNA in the mature generative cells of Chlorophytum spp. (Liliaceae) 总被引:1,自引:0,他引:1
Summary. Following 4′,6-diamidino-2-phenylindole staining of mature pollen grains of Chlorophytum comosum, fluorescence microscopy confirmed that cytoplasmic nucleoids (DNA aggregates) were present in the generative cells, which
indicated the possibility of biparental cytoplasmic inheritance. Electron and immuno-electron microscopy showed that both
plastids and mitochondria were present in the generative cells, and both organelles contained DNA. These results indicate
that mitochondria and plastids of C. comosum have the potential for biparental inheritance. Similar results were obtained with mature pollen grains of C. chinense. Therefore, we conclude the coincident biparental inheritance for mitochondria and plastids in the members of the genus Chlorophytum.
Received June 28, 2002; accepted September 26, 2002; published online April 2, 2003
RID="*"
ID="*" Correspondence and reprints: College of Life Science, Peking University, Bejing 100871, People's Republic of China. 相似文献
20.
Summary. Preprophase bands in the neck canal mother cell and the central cell of the archegonium of the fern Dryopteris crassirhizoma are observed with immunofluorescence microscopy. No phragmoplast is found during mitosis of the neck canal mother cell; however,
the phragmoplast develops very well in the central cell. The neck canal mother cell undergoes karyokinesis but not cytokinesis
and finally produces only one binucleate neck canal cell. However, the central cell undergoes cytokinesis and produces an
egg cell and a ventral canal cell. These observations suggest that the preprophase band in the neck canal mother cell loses
its function as a cytokinetic apparatus and becomes an evolutionary vestige in the development of the archegonium.
Received January 22, 2002; accepted April 26, 2002; published online October 31, 2001
RID="*"
ID="*" Correspondence and reprints: College of Life Sciences, Peking University, Beijing 100871, Peoples' Republic of China.
E-mail: rlyou@pku.edu.cn 相似文献