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1.
Walter H. Adey 《Hydrobiologia》1965,26(3-4):539-573
Summary This paper is the second of a series covering the crustose corallines of the Gulf of Maine. Information on anatomy, cytology and the development of the reproductive structures is presented to show that Clathromorphum is a genus distinct from both Phymatolithon and the branching members of Lithothamnium. Also, for the two species of this genus present in the region, reproductive cycles and geographic and bathymetric distributions are presented and discussed.Part of a study undertaken while working on a Ph. D. program at the University of Michigan. The necessary field work was made possible by the generous support of: the American Petroleum Institute (Grant-in-aid No. 85), the Geological Society of America (Penrose Grant No. 912-62), the Office of Naval Research (Nonr 1841 (74), through the Department of Geology and Geophysics, Massachusetts Institute of Technology) and the Woods Hole Oceanographic Institution.  相似文献   

2.
Chromosomes of the murine leukemia virus indicator cell line XC   总被引:1,自引:0,他引:1  
A cell line derived from the Rous Sarcoma Virus induced rat tumor XC (Svoboda), which was recently utilized as an indicator for the presence of murine leukemia virus growing in mouse cells, has been examined karyologically. The cells differ considerably from each other as well as from the normal rat karyotype (Rattus norvegicus, 2n=42). The modal chromosome number is 41. All cells bear one or more chromosome markers in common as well as non-rat-like chromosomes, but rat-like chromosomes still preserve the identity of species origin.Supported by Contract No. PH 43-63-13 between the University of California and the National Cancer Institute, National Institutes of Health (Special Virus Cancer Program).  相似文献   

3.
A method for the starch gel electrophoresis of human L-glutamate dehydrogenase (GLUD) is described, as is the tissue distribution of GLUD detected by this method. Extracts of livers from 200 Whites were analyzed without demonstration of an electrophoretic variant. The molecular size was estimated to be 330,000 and the isoelectric point pH 4.83.This investigation was supported by Public Health Service Grant No. 1 F22 CAO2083-01 of the National Cancer Institute.  相似文献   

4.
Somatic chromosomes of a female and male Himalayan thar, Hemitragus jemlahicus (H. Smith) are described. The diploid number is 48, there are 12 atelocentric and 34 telocentric autosomes in both sexes, the X-chromosome is meta- or submetacentric. The morphological appearance of the Y-chromosome is compared with that of other bovid species including recent observations on the goat Capra hircus.Supported by Contract No. PH 43-63-13 between the National Cancer Institute of the National Institutes of Health and the University of California.  相似文献   

5.
After the further studies on the open dichotomous leaf venation ofKingdonia andCircaeaster, we considered that the venation of these genera is incomparable to that of some gymnosperms such as Ginkgoaceae, and is a degenerated characteristic in the morphological nature. We also considered that this characteristic is very important on determining the systematic relationship between these genera and other members of Ranunculales (sensu Takhtajan 1980), but its implication in the phylogeny of angiosperms was overemphasized. The project was supported by The National Natural Science Foundation of China (No. 39630030) and The Laboratory of Systematic & Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences.  相似文献   

6.
Pioneer works on studying molecular mechanisms of mutagenesis were published in the journal Genetika in the 1960s. In the laboratory of S.I. Alikhanian, studies on molecular mechanisms of genetic transposition were initiated in the late 1960s on the model of bacteriophage transposon Mu (Mutator). Parallel to these studies conducted in the laboratory of plant molecular genetics (Institute of Molecular Genetics, Academy of Sciences of the USSR), which was later named the Laboratory of Functional Genomics (Vavilov Institute of General Genetics, Russian Academy of Sciences), studies on transposition of Ti-plasmid T-DNA of Agrobacterium tumefaciens and works on construction of transgenic plants began in this laboratory. Transgenic plants with the expressed bacterial genes provided a model for the functional genomics. This topic is considered here in detail.__________Translated from Genetika, Vol. 41, No. 4, 2005, pp. 440–454.Original Russian Text Copyright © 2005 by Piruzian.In connection with the anniversary of the Russian Journal of Genetics, this review is dedicated to the memory of one of the founders of this journal, an outstanding Russian geneticist, my mentor Professor S.I. Alikhanyan.  相似文献   

7.
Scott Allen and John P. Craven, editors, Alternatives in Deepsea Mining, Proceedings, Law of the Sea Institute Workshop, December 11–14, 1978, Ka'u Hawaii (Honolulu: Law of the Sea Institute, University of Hawaii, 1979), vii + 110 pp., $12.50.

Jack N. Barkenbus, Deep Seabed Resources: Politics and Technology (New York: The Free Press, 1979), xiv + 191 pp., $14.95.

Ross D. Eckert, The Enclosure of Ocean Resources: Economics and the Law of the Sea (Stanford: Hoover Institution Press, Stanford University, 1979), xiv + 390 pp., $16.95.

I. G. Bulkley, Who Gains From Deep Ocean Mining? Simulating the Impact of Regimes for Regulating Nodule Exploitation, Research Series No. 40 (Berkeley: Institute of International Studies, University of California, 1979), vii + 117 pp., $3.50 (paper).

Judith T. Kildow, editor, Deepsea Mining (Cambridge, MA: The MIT Press, 1980), vii + 110 pp., $2.50.  相似文献   

8.
Anthocyanin synthesis in the broom sorghum, Sorghum bicolor Moench cvs. Acme Broomcorn and Sekishokuzairai-Fukuyama, is mediated separately or synergistically by an ultraviolet light-B (UV-B) photoreceptor and phytochrome. When seedlings were exposed to moderate low temperatures ranging from 12 to 20° C before irradiation, only the phytochrome-mediated anthocyanin synthesis was markedly enhanced compared with the control, which was kept throughout at 24° C; synthesis mediated by the UV-B photoreceptor was unaffected. The effectiveness of an exposure to 20° C increased as the duration of exposure increased up to 24 h and as the time of exposure became closer to the time of irradiation. However, when seedlings were exposed to 20° C from after irradiation until harvest, anthocyanin syntheses induced by both UV-B and red light were equally suppressed, probably due to the general reduction of metabolism involved in anthocyanin synthesis that is a consequence of lower temperature. The results support the view that the signal transduction of the pyhtochrome system is different from that of the UV-B photoreceptor, and indicate that the phytochrome system may involve a step or steps which are amplified by a previous exposure to the moderate low temperature.Abbreviations FR far-red light - LT low temperature - MLT moderate low temperature - Pfr far-red-light-absorbing form of phytochrome - R red light - UV ultraviolet light - UV-B ultraviolet light-B We thank Drs. Y. Takeuchi (Shionogi Pharmaceutical Company, Aburahi, Shiga) and K. Hosaka (the Experimental Farm, Kobe University, Kasai) for seeds; Dr. M. Watanabe and Mr. M. Kubota (the National Institute for Basic Biology, Okazaki) for operation of the spectrograph. This work was supported by grants from the Yamada Science Foundation, Ministry of Education (No. 63480015 and 03454048), and the National Institute for Basic Biology (Large Spectrograph grant No. 91-523).  相似文献   

9.
Adult Drosophila melanogaster flies collected from populations broadly dispersed over ecological and geographic strata of North Carolina, and over a period of 4 years, were analyzed for alcohol dehydrogenase phenotypes by gel electrophoresis. Gene frequencies in spring-summer-fall field collections were remarkably stable over all strata. Two winter collections exhibited contrasting gene frequency changes. In one case the results are interpreted in terms of long-distance migration from Florida, while the other is explicable by assignment of a causal role to environmental factors which accompany the winter season.This investigation was supported in part by NIH Research Grant No. GM11546 from the National Institute of General Medical Sciences and by Contract No. AT-(40-1)-3980 from the United States Atomic Energy Commission.Paper No. 4719 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina 27609.  相似文献   

10.
 Two Exobasidium species causing Exobasidium leaf blister on Rhododendron spp. are described. An Exobasidium leaf blister on Rhododendron yedoense var. yedoense f. yedoense has been recognized in Hokkaido Prefecture, Japan, since the first report was issued in 1950. The causal fungus is identified with Exobasidium dubium from the morphology of its hymenial structure and mode of germination of the basidiospores. Another Exobasidium leaf blister on Rhododendron dauricum has been observed in Hokkaido Prefecture, Japan. In comparison with morphology based on hymenial structure and mode of germination of the basidiospores of the 100 validly described taxa, this fungus differs from those known taxa in the size of basidia and basidiospores, the numbers of sterigmata and septa of basidiospores, and the mode of germination of basidiospores. Thus, a new species, Exobasidium miyabei, is established and illustrated. Received: February 13, 2002 / Accepted: September 25, 2002  Present address: National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan Acknowledgments We profoundly appreciate the cooperation of Dr. V. Melnik in providing Russian papers and Dr. L. Vasilyeva for translating them into English. We thank Prof. H. Takahashi for loaning the materials in the Herbarium of the Hokkaido University Museum and Dr. W. Abe, Graduate School of Science, University of Hokkaido, for his kind help with the sampling of R. dauricum in Teshikaga, Hokkaido Prefecture. This study was supported in part by a Grant-in-Aid for Scientific Research (B) (No. 13460019), Japan Society for the Promotion of Science (JSPS). Contribution No. 171, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba. Correspondence to:M. Kakishima  相似文献   

11.
Phosphoglucomutase (PGM) of red cells was examined in 15 inbred strains of mice, using two different starch gel electrophoretic buffer systems. Two new alleles, Pgm-1 c and Pgm-1 d, were discovered at the Pgm-1 locus. Pgm-1 c was first identified in strain C3H/HeNWe and Pgm-1 d in 129/ReWl. No variation was observed at the Pgm-2 locus.Supported in part by USPHS Pre-doctoral Fellowship No. 5 F1 GM-32,680, USPHS Research Resources Grant No. 5-PO6 RR 00343-05, USPHS (National Cancer Institute) Chemotherapy Contract 71-2010, and Biomedical Sciences Support Grant FR 07037 to the University of Kansas.  相似文献   

12.
Summary On the basis of a recent physical theory of many-body problems developped in our Institute, a model of the brain is formulated, and it is shown how some of its typical features, such as learning and memory processes, find therein a natural and simple explanation. In the Appendix a short surview of the necessary mathematical formalism is finally given.A brief outline of the model presented in this paper was unformally given by one of the authors (L.M.R.) at the I.S.P. Neurosciences Research Program; Boulder Colorado, in July 1966.This work has been sponsored in part by: Air Force Avionics Lab., Research and Technology Div., Wright Patterson Air Force, Air Force System Commend-U.S.A.F.-Government of United States of America. Contract No. AF 33(615)-2786.  相似文献   

13.
Summary The diploid number of chromosomes in Calotes versicolor is 34 in the male and 33 in the female. The numerical difference in the two sexes is based on the condition of the sex chromosome; in the male it is present as a homologous pair, while in the female it remains unpaired. The sex chromosome was identified as one of the micro-chromosomes (the chromosome No. 7) in this species. Sitana ponticeriana possesses the diploid number of 46 in the male and 45 in the female. The sex chromosome identified in this form is also one of the micro-chromosomes (chromosome No. 13), which has no partner in the female, whereas in the male it is in the paired state having a homologous mate.It was established therefore that, in both species studied, the female is heterogametic as regards the sex chromosome.The chromosome complement of Calotes versicolor consists of 12 V-shaped macro-chromosomes and 22 dot-like micro-chromosomes, while in Sitana ponticeriana there are 24 rod-shaped macro-chromosomes and 22 dot-like micro-chromosomes. The difference in the karyotypes of these two species can be accounted for on the basis of the formation of V-shaped multiple chromosomes by means of the fusion of two rods at the point of fibre attachment.The karyological relationships in the Family Agamidae were discussed. The chromosome number previously reported for Uromastix hardwicki was found to be erroneous; the diploid number in this species is 34.Contribution No. 214 from the Zoological Institute, Faculty of Science, Hokkaido University, Sapporo, Japan.  相似文献   

14.
Summary. Autophagy is a process in which cell membrane rearrangement allows for the sequestration and degradation of part of the cytoplasm. Many protein components of the autophagic mechanism and their corresponding genes have been identified in yeast cells by molecular genetics, and this has enabled researchers to identify homologues of these genes in mammalian and plant systems. Autophagy is involved in the starvation response in which part of the cytoplasm is degraded in order to produce essential substrates to allow the cell to survive during extreme substrate-limiting conditions. However, autophagy may also be important as a quality control mechanism in normal cells. By screening Arabidopsis thaliana T-DNA insert mutants, we isolated an A. thaliana mutant that lacks the AtTIC40 gene and found that the cotyledon cells of this mutant contained undeveloped plastids. Moreover, many toluidine-stained particulate structures were found in the vacuoles of these mutant cells. The images from electron microscopy suggested that some of these particulate structures were partially degraded chloroplasts. Furthermore, oil bodies were found in the cotyledon cells of mutant and wild-type plants, which suggests that the mutant seedlings were not starved under the experimental conditions. These results may indicate that under nutrient-sufficient conditions, plant cells remove abnormal plastids by autophagy and that this mechanism is involved in the quality control of organelles.Present address: BioResource Center, Tsukuba Institute, Institute of Physical and Chemical Research (RIKEN), Tsukuba, Japan.Present address: Genomics Sciences Center, Yokohama Institute, Institute of Physical and Chemical Research (RIKEN), Yokohama, Japan.Correspondence and reprints: School of Food and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan.  相似文献   

15.
Anelementary system is defined as two compartments, one the immediate and unique precursor of the other. By synthesizing a number of elementary systems, we can obtain a system with any givenweight, transfer time anddispersion. A criterion is presented to choose the best model of a given system, i.e. a system with the same above parameters and composed of a minimum number of elementary systems. Supported in part by NIH grant NO. GM-572. Supported by PHS Training grant No. 2T01 HE05138-17 from the National Heart Institute.  相似文献   

16.
Electrophoretic variants of two carbonic anhydrase enzymes, CAR-1 (CA I) and CAR-2 (CA II), have been found in the laboratory mouse, Mus musculus. These two loci are closely linked to each other and are located on chromosome 3 near its centromere. The close linkage of Car-1 and Car-2 supports the hypothesis that the present-day carbonic anhydrase loci are the result of tandem duplication of an earlier carbonic anhydrase locus with subsequent divergence. The red blood cells of mice of the subspecies M. m. casteneus have significantly reduced levels of CAR-1 and CAR-2.This research was supported in part by Research Grants GM-20919 from the National Institute of General Medical Sciences and CA-01074 from the National Cancer Institute, and by Contracts E(11-1)-3267 with the Energy Research and Development Administration and NO1-ES-4-2159 with the National Institute of Environmental Health Sciences. The Jackson Laboratory is fully certified by the American Association for Accreditation of Laboratory Animal Care.  相似文献   

17.
The effect of high nonexchangeable aluminum on availability of nitrogen (N) and phosphorus (P) was studied in a Cryptopodzolic soil (Cademario) derived from mica schist in southern Switzerland. The research involved a greenhouse pot experiment comparing growth of barley on soil samples of three soil layers (10- to 25-, 40- to 60- and 70- to 90 cm) of the Cademario profile, representing a range of Al and organic matter properties, with the 10- to 40 cm layer of a profile of an acidic brown earth (Haplumbrept), derived from cherty limestone. The experiment, which included four nutrient treatments [check, N0 (PKS), P0 (NKS) and full (NPKS)], lime and no lime treatments and four replicates, was supplemented by soil chemical analysis. Results showed that liming alone produced greater yield responses in the Cademario soil than N or P added singly or together. On unlimed soils, barley yield for check, N0, and P0 treatments showed a positive linear relation with exchangeable Ca of soils and a negative linear relation with organically-complexed Al. Failure of liming to influence Pav, especially when combined with P fertilization, suggests that P was quickly absorbed on highly active surfaces formed from initially exchangeable Al.This research is a cooperative effort of the Arizona Agricultural Experiment Stations, Journal Article No. 7100 and the Swiss Federal Institute for Forest, Snow and Landscape; it was supported by the National Science Foundation, USA, Grant No. INT-8304490, and the Swiss National Science Foundation, Grant No. 2.919-803.This research is a cooperative effort of the Arizona Agricultural Experiment Stations, Journal Article No. 7100 and the Swiss Federal Institute for Forest, Snow and Landscape; it was supported by the National Science Foundation, USA, Grant No. INT-8304490, and the Swiss National Science Foundation, Grant No. 2.919-803.  相似文献   

18.
Summary An ultrastructural study of in vitro maturation of A. punctulata oocytes was undertaken to determine when heavy body formation was initiated. No heavy bodies were seen in germinal vesicle oocytes or in oocytes undergoing germinal vesicle breakdown or polar body formation. Heavy bodies were only observed in ova examined one to two hours after pronuclear formation. Several small heavy bodies were seen in sections of eggs fixed as early as three hours after the pronucleus had formed. The number of these structures in the egg cytoplasm increased with time. Therefore it is concluded that heavy body formation in sea urchin ova is a phenomenon following nuclear maturation.Contribution No. 222 from the Institute for Molecular and Cellular Evolution. Supported in part by grants from the National Institutes of Health (5-T01-HD00026-09 to the Fertilization and Gamete Physiology Training Program at the Marine Biological Laboratory and predoctoral fellowship 1-F01-GM-36,719-01A1 to C. M. Conway) and the National Science Foundation (GB3899 to C. B. Metz).The authors are grateful to Drs. A. F. Conway, Giovanni Giudice, and Gertrude W. Hinsch for consultation and criticism of this work.  相似文献   

19.
Summary Biopsies taken from cases of microsporosis caused byMicrosporon audouinii orM. canis were sectioned. Ultraviolet microscopy revealed that the fluorescent matter is located only in the cortex and medulla of the hair. Neither intrapilary hyphae nor the sheath of arthrospores surrounding the infected hair fluoresce.These investigations were supported by a grant from the John A. Hartford Foundation, Inc., New York, New York and in part, training grant No. 2A-5289 (C4), from the National Institute of Arthritis and Metabolic Diseases, U.S. Public Health Service, Bethesda, Maryland 20014.  相似文献   

20.
Summary The prothoracic glands of female pupae of Xyleborus ferrugineus at three ages (0-h, 48-h and 72-h-old) were examined for ultrastructural changes that correlate with high titers of ecdysteroids in the entire pupa.In all three ages, the prothoracic gland cells appear compact with a prominent nucleus. Lysosome-like structures with concentrically oriented internal membrane are observed in both 0-h and 72-h-old gland cells. Mitochondria are abundant in the glands of both ages, and rough endoplasmic reticulum is relatively sparse. Numerous microtubules are present in the prothoracic gland cells of 48-h-old female pupae that contain relatively high titers of ecdysteroids. Rough endoplasmic reticulum also is especially abundant at this age of the pupa. Ecdysone titers, estimated by the radioimmunoassay method (RIA), were 161.04±22.61 pg/mg, 704.25±69.02 pg/mg and 298.72±26.80pg/mg body weight in 0-h, 48-h and 72-h-old female pupae, respectively.This research was supported by the College of Agricultural and Life Sciences, University of Wisconsin, Madison; and in part by research grants No. RR-00779, Division of Research Resources, and No. AG-01271, Institute on Aging, of the National Institutes of Health; and No. PFR 77-08279 from the National Science Foundation to D.M.N.We thank especially Jon Gundersen and Steven Schnurrer for extensive and invaluable technical assistance during this research  相似文献   

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