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1.
Committee Members: D. Epstein, T.A. Howard, D. Malo, F. Mancino, M. Mehrabian, K.J. Moore, R.J. Oakey, S. Reinehez-Videl, K. Steel and M.L. Watson.  相似文献   

2.
Further trajectory studies on the C+ + H2O reaction have been performed using a potential energy surface described through a finite element method in its p version. In former trajectory studies [Y. Ishikawa, T. Ikegami and R.C. Binning Jr., Direct ab initio molecular dynamics study of C++H2O: angular distribution of products and distribution of product kinetic energies, Chem. Phys. Lett. 370 (2003), pp. 490–495; J.R. Flores, Quasichemical trajectories on a finite element density functional potential energy surface: the C++H2O reaction revisited, J. Chem. Phys. 125 (2006), 164309], tunnelling was not taken into account. The present results together with the analysis of the electronic excited states [J.R. Flores and A.B. González, The role of the excited electronic states in the C++H2O reaction, J. Chem. Phys. 128 (2008), 144310] are useful to interpret the mechanism of the title reaction, which has been the subject of crossed beam experiments [D.M. Sonnenfroh, R.A. Curtiss and J.M. Farrar, Collision complex formation in the reaction of C+ with H2O, J. Chem. Phys. 83 (1985), pp. 3958–3964] and can be considered a prototypical ion–molecule reaction.  相似文献   

3.
4.
5.
《Ibis》1968,110(2):221-225
Bagge , P., Lehtovouri , M. & Lindqvist , O. 1963. [Quantitative investigations of the bird fauna of Inari and Enontekiö in northern Lappland.] Bailey , R. S. 1967. An index of bird population changes on farmland. Brenner , F. J. 1966. The influence of drought on reproduction in a breeding population of Redwinged Blackbirds Agelaius phoeniceus. Davis , B. N. K. 1967. Bird feeding preferences among different crops in an area near Huntingdon. Dick , J. A. & Rising , J. D. 1965. A comparison of foods eaten by Eastern Kingbirds and Western Kingbirds in Kansas. Evans , F. C. 1964. The food of Vesper, Field, and Chipping Sparrows nesting in an abandoned field in Southeastern Michigan. Haapanen , A. 1965. Bird fauna of the Finnish forests in relation to forest succession. Hildén , O. 1964. Ecology of duck populations in the island group of Valassaaret, Gulf of Bothnia. Jenkins , D., Watson , A. & Miller , G. R. 1964. Current research on Red Grouse in Scotland. Kear , J. 1962. Feeding habits of the Grey Lag Goose Anser anser on the Island of Bute. Kear , J. 1965. Recent changes in Scottish barley acreages and the possible effect on wild geese. KEAR, J. 1967. Feeding habits of the Greylag Goose Anser unser in Iceland, with reference to its interaction with agriculture. Kikkawa , J. 1966. Population distribution of land birds in temperate rainforest of southern New Zealand. Kulczycki , A. 1966. [The birds of the Lańcut Park.] Murton , R. K. 1965. Natural and artificial population control in the Wood-Pigeon. Murton , R. K. c. 1966. A statistical evaluation of the effect of Wood-Pigeon shooting as evidenced by the recoveries of ringed birds. Nelson , J. B. 1966. Population dynamics of the Gannet (Sula bassana) at the Bass Rock, with comparative information for other Sulidae. Paynter , R. A. 1966. A new attempt to construct life tables for Kent Island Herring Gulls. Pulliainen , E. 1963. On the history, ecology, and ethology of the Mallards (Anas platyrhynchos L.) overwintering in Finland. Ratcliffe , D. A. 1967. The Peregrine situation in Great Britain 1965–66. Schemnitz , S. D. 1964. Comparative ecology of Bobwhite and Scaled Quail in the Oklahoma Panhandle. Skead , C. J. 1967. Ecology of birds if the Eastern Cape Province. Sladen , W. J. L., Wood , R. C. & Emison , W. B. 1966. Antarctic avian population studies, 1965–66. Snow , D. W. & Snow , B. K. 1961. Breeding seasons and annual cycles of Trinidad land-birds. Snow , D. W. 1966. Population dynamics of the Blackbird. Soikkeli , M. 1965. On the structure of the bird fauna of some coastal meadows in western Finland. Watson , A. 1965. Research on Scottish Ptarmigan. Watson , A. 1966. Hill birds of the Cairngorms. Westerskov , K. 1965. Winter ecology of the Partridge Perdix perdix in the Canadian Prairie. Williamson , K. 1964. Bird Census work in Woodland. Williamsonj , K. 1967. The bird community of farmland. Willson , M. F. 1966. Breeding ecology of the Yellow-headed Blackbird.  相似文献   

6.
Book reviews     
《Austral ecology》1992,17(3):352-357
Books reviewed in this article: Plant Community History: Long-term Changes in Plant Distribution and Diversity
J. H. Tallis Global Forest Resources
A. S. Mather Species Dispersal in Agricultural Habitats
Edited by R. G. H. Bunce and D. C. Howards The Australian Dragonflies: A Guide to the Identification, Distributions, and Habitats of Australian Odonata
J. A. L. Watson, G. Theischinger and H. M. Abbey Monsoonal Australia: Landscape, Ecology and Man in the Northern Lowlands
Edited by C. D. Haynes, M. G. Ridpath and M. A. J. Williams, A. A. Balkema Ferns and Allied Plants of Victoria, Tasmania and South Australia
B. D. Duncan and G. Isaac Ferns of Queensland
S. B. Andrews Introduction to Vegetation Analysis
D. R. Causton, Unwin Hyman  相似文献   

7.
The use of hair for the assessment of human mineral nutritional status is controversial, yet has potential because of the ease of collection and storage, and the high concentration of minerals in hair. This study generated baseline values for hair macromineral content in the most commonly used primate model for human nutrition and disease, the rhesus monkey. Hair digests from monkeys in Maryland (n=98) and Puerto Rico (n=208) were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Significant differences existed between the two populations for hair calcium (Ca), magnesium (Mg), and phosphorus (P) (P<0.01,P<0.001,P<0.02). Male hair had higher concentrations of Mg in specimens from the Puerto Rican population (P<0.001), whereas hair phosphorus was higher in female hair (P<0.02). There were no significant differences attributable to pregnancy status. Differences in hair content attributable to categorical age were found for Ca and Mg (P<0.001,P<0.01). Significant location differences paralleled dietary differences. These values therefore can be considered reference ranges for hair Ca, Mg, and P for free-ranging and caged rhesus monkeys. Preliminary reports of portions of these data were presented at the 69th Annual Meeting of the Federation of American Societies for Experimental Biology, April 1982, New Orleans, LA (B. M. Marriott, J. C. Smith, R. Jacobs, A. O. Jones, M. J. Kessler, and R. Rawlins,Fed. Proc. 41:770 [1982]) and in a symposium at the 6th Annual Meeting of the American Society of Primatologists, 1983, East Lansing, MI (B. Marriott, J. C. Smith, R. Jacobs, A. O. Lee Jones, R. Rawlins, and M. J. Kessler,Am. J. Primatol. 4(3):157 [1983]; B. Marriott, J. C. Smith, Jr., R. M. Jacobs, A. O. Lee Jones, R. Rawlins, and M. J. Kessler, inThe Cayo Santiago Macaques, R. Rawlins and M. J. Kessler, eds., SUNY Press, Albany, NY, pp. 219–231 [1986]).  相似文献   

8.
Proton and phosphorus nmr have been used to investigate the double-helical structures of polyriboadenylic acid [poly(A)] formed in acidic solutions (pH < 6). The results obtained at low pH (~4.5) are consistent with the model for the acid poly(A) double helix proposed by Rich [Rich, A., Davies, D. R., Crick, F. H. C. & Watson, J. D. (1961) J. Mol. Biol. 3 , 71–86]. Other models that have been proposed are inconsistent with the nmr data. The nmr measurements have also been used to examine the conformation of poly(A) helix in the half-protonated state. Although the base-stacking arrangement of this state is similar to that observed in the more extensively protonated low-pH state, the phosphate backbone conformation is different from that found in either the neutral or low-pH structures.  相似文献   

9.
Book reviews     
Book reviews in This Article:
Detection of Bacterial Endotoxins with the limulus amebocyte lysate Test (1987). Edited by Stanley W. Watson, Jack Levin & Thomas J. Novitsky.
Computers in Microbiology (1987). Edited by J.D. Rant, R.K.A. Feltham & W. Shepherd.
Molecular Strategies of Parasite Invasion (1987). Edited by N. Agabian, H. Goodman & N. Nogueira.
Footrot in Ruminants (1986). Edited by D.J. Stewart, J.E. Peterson, N.M. McKern & D.L.
Bacterial Protein Toxins (1986). Edited by P. Falmagne, J.E. Alouf, F.J. Fehrenbach, J. Jeljaszewicz & M. Thelestam.
Carbon Substrates in Biotechnology (1987). Edited by J.D. Stowell, A.J. Beardsmore, C.W. Keevil & J.R. Woodward.  相似文献   

10.
R. J. Hobbs 《Plant Ecology》1984,57(2-3):129-136
Studies on a long-term experiment on Calluna-Eriophorum bog indicate that the length of time between management fires affects the post-fire development. A short rotation (every 10 years) results in increased dominance by Eriophorum spp. while a long rotation (every 20 years) results in greater abundance of Calluna vulgaris after fire. Variations in post-fires species abundances are related to pre-fire stand composition coupled with the patchy distribution of regeneration centers of rhizomatous species. The usefulness of burning this vegetation type in management for herbivore grazing is questioned.Nomenclature follows Tutin et al. (1964 80) for vascular plants. Smith (1978) for mosses, Watson (1981) for liverworts and Hawksworth, James & Coppins (1980) for lichens. Following common practice. Calluna vulgaris is referred to simply as Calluna. Acknowledgements. I thank M. Raves and the Nature Conservancy Council for permission to work on Moor House National Nature Reserve and for the use of data from Reserve Records, V. J. Hobbs for field assistance, and Prof. C. H. Gimingham for help and advice during the study. I also thank all who worked at Moor House for creating a pleasant working environment. The long-term experiment was planned by Dr R. J. Elliot and analyzed initially by Dr G. I. Forrest.  相似文献   

11.
The concentrations of the elements copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) in hair of caged (in Maryland) and freeranging (in Puerto Rico) rhesus monkey populations were determined. Significant chronological age-related decreases were evident for the trace elements Mn and Zn in both populations (P<0.01) and for Cu and Fe in free-ranging monkeys (P<0.005). The only overall gender difference was higher hair Mn concentration in freeranging males than in females (P<0.03). There were no significant differences in hair Cu, Fe, or Mn related to pregnancy status. Hair Zn was lower in samples from pregnant than from nonpregnant monkeys from the caged monkeys (P≤0.05), but did not differe in the freeranging monkeys. Comparison of the two populations revealed that hair Zn levels were significantly higher in caged vs free-ranging animals (P<0.001). We attribute this higher hair Zn in the caged monkeys to contact and ingestion of Zn from their galvanized enclosures. Hair iron levels were significantly higher (P<0.001) in free-ranging monkeys, possibly as a result of Fe-rich soil ingestion from their environment. These data support continued investigation of the use of hair as an indicator of the exposure of large groups or populations to potentially high levels of specific minerals, and the use of nonhuman primates as models for the study of trace element deficiency and/or toxicity in humans. Prelliminary reports of portions of these data were presented at the 69th Annual Meeting of the Federation of American Societies for Experimental Biology, April 1982, New Orleans, LA (B. M. Marriott, J. C. Smith, R. Jacobs, A. O. Jones, M. J. Kessler, and R. Rawlins,Fed. Proc. 41:770, [1982]) and in a symposium at the 6th Annual Meeting of the American Society of Primatologists, 1983, East Lansing, MI (B. Marriott, J. C. Smith, R. Jacobs, A. O. Lee Jones, R. Rawlins, and M. J. Kessler,Am. J. Primatol. 4(3): 157 [1983]; B. Marriott, J. C. Smith, Jr., R. M. Jacobs, A. O. Lee Jones, R. Rawlins, and M. J. Kessler, inThe Cayo Santiago Macaques, R. Rawlins and M. J. Kessler, eds., SUNY Press, Albany, NY, pp. 219–231 [1986]).  相似文献   

12.
The Solid phase synthesis (SPS) concept, first developed for biopolymers, has spread in every field where organic synthesis is involved. While the potential of the solid-phase method was obvious in 1959 to its discoverer, Prof. R. B. Merrifield, it was unpredictable its dominance in peptide synthesis and especially in combinatorial chemistry, an area not yet conceived. SPS paved the way for solid-phase combinatorial approaches (extensively reviewed in (Choong, I. C. and Ellman, J. A.: 1996, Annu. Rep. Med. Chem. 31, 309–318; Obrecht, D. and Villalgordo, J. M.: 1998, Solid-supported Combinatorial and Parallel Synthesis of Small-Molecular-Weight Compound Libraries. Pergamon Press Ltd., Oxford, UK; Chabala, J. C.: 1995, Curr. Opin. Biotechnol. 6, 632–639; Kamal, A., Reddy, K. L., Devaiah, V., Shankaraiah, N., Reddy, D. R.: 2006, Mini Rev. Med. Chem. 6, 53–69; Whitehead, D. M., McKeown, S. C., Routledge, A.: 2005, Comb. Chem. HTS 8, 361–371; Nefzi, A., Ostresh, J. M., Houghten, R. A.: 1997, Chem. Rev. 97, 449–472; Gordon, E. M., Gallop, M. A., Patel, D. V.: 1996, Acc. Chem. Res. 29, 144–154)) as many laboratories and companies focused on the development of technologies and chemistry suitable to this new methodology. This resulted in the spectacular outburst of combinatorial chemistry, which profoundly changed the approach for new drug discovery. Combinatorial chemistry is currently considered a valid approach for a wide range of biomedical applications, such as, target validation and drug discovery.  相似文献   

13.
Chiung-Yu  Huang Xianghua  Luo 《Biometrics》2008,64(3):987-988
The Statistical Analysis of Recurrent Events (R. J. Cook and J. F. Lawless) Chiung‐Yu Huang and Xianghua Luo Introduction to Empirical Processes and Semiparametric Inference (M. R. Kosorok) Changyong Feng Uncertain Judgements: Eliciting Experts' Probabilities (A. O'Hagan, C. E. Buck, A. Daneshkhah, J. R. Eiser, P. H. Garthwaite, D. J. Jenkinson, J. E. Oakley, and T. Rakow) James M. Dickey Models for Intensive Longitudinal Data (T. A. Walls and J. L. Schafer, editors) Daniel Farewell Quantitative Environmental Risk Analysis for Human Health (R. A. Fjeld, N. A. Eisenberg, and K. L. Compton) Scott M. Bartell Reliable Reasoning: Induction and Statistical Learning Theory (G. Harman and S. Kulkarni) Oliver Schulte Modeling Infectious Diseases in Humans and Animals (M. J. Keeling and P. Rohani) Carol Y. Lin Cluster and Classification Techniques for the Biosciences (A. H. Fielding) Morven Leese Modern Applied U‐Statistics (J. Kowalski and X. M. Tu) Jesse Frey Handbook of Statistical Genetics, 3rd edition (D. J. Balding, M. Bishop, and C. Cannings, editors) Karin Bammann, Ronja Foraita, Frauke Günther Quality of Life: The Assessment, Analysis, and Interpretation of Patient‐Reported Outcomes, 2nd edition (P. M. Fayers and D. Machin) Jeff A. Sloan, Amylou Dueck, Rui Qin, Wenting Wu, Pamela J. Atherton, Paul Novotny, Heshan Liu, Kelli N. Burger, Angelina D. Tan, Daniel Szydlo, Victor M. Johnson, Sara J. Felten, Xinghua Zhao, and Brent Diekmann Advanced Distance Sampling: Estimating Abundance of Biological Populations (S. T. Buckland, D. R. Anderson, K. P. Burnham, J. L. Laake, C. L. Borchers, and L. Thomas) Carl James Schwarz Brief Reports by the Editor The Construction of Optimal Stated Choice Experiments: Theory and Methods (D. J. Street and L. Burgess) Design and Analysis of Experiments, Volume 1: Introduction to Experimental Design, 2nd edition (K. Hinkelmann and O. Kempthorne) Introduction to Bayesian Statistics, 2nd edition (W. M. Bolstad) Asymptotic Theory of Statistics and Probability (A. Dasgupta) Bootstrap Methods: A Guide for Practitioners and Researchers, 2nd edition (M. R. Chernick)  相似文献   

14.
With the completion of genome sequencing projects, there are a large number of proteins for which we have little or no functional information. Since protein function is closely related to three-dimensional conformation, structural proteomics is one avenue where the role of proteins with unknown function can be investigated. In the present structural project, the structure of MTH187 has been determined by solution-state NMR spectroscopy. This protein of 12.4 kDa is one of the 424 non-membrane proteins that were cloned and purified for the structural proteomic project of Methanobacterium thermoautotrophicum [Christendat, D., Yee, A., Dharamsi, A., Kluger, Y., Gerstein, M., Arrowsmith, C.H. and Edwards, A.M. (2000) Prog. Biophys. Mol. Biol., 73, 339–345]. Methanobacterium thermoautotrophicum is a thermophilic archaeon that grows optimally at 65 °C. A particular characteristic of this microorganism is its ability to generate methane from carbon dioxide and hydrogen [Smith, D.R., Doucette-Stamm, L.A., Deloughery, C., Lee, H., Dubois, J., Aldredge, T., Bashirzadeh, R., Blakely, D., Cook, R., Gilbert, K., Harrison, D., Hoang, L., Keagle, P., Lumm, W., Pothier, B., Qiu, D., Spadafora, R., Vicaire, R., Wang, Y., Wierzbowski, J., Gibson, R., Jiwani, N., Caruso, A., Bush, D., Reeve, J. N. et al. (1997) J. Bacteriol., 179, 7135–7155].Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users. Structure data have been deposited at PDB (1TE4) and NMR data at BMRB (5629).Olivier Julien and Isabelle Gignac - Both authors contributed equally to this work.  相似文献   

15.
Book reviewed in this article: Die Milben des Süsswassers (Hydrachnellae und Halacaridae [part.], Acari) Teil 1: Bibliographie, Teil 2: Katalog, by Kurt O. Viets. A Primate Radiation: Evolutionary Biology of the African Guenons, edited by Annie Gautier-Hion, F. Bourlière, J.-P. Gautier and J. Kingdon. Neurobiology of the Cardiorespiratory System, edited by E. W. Taylor. The Dragonflies of Europe, by R. R. Askew. Studying Fossil Horses, by V. Eisenmann, M. T. Alberdi, C. de Giuli & U. Staesche. Collected papers after the ‘New York International Hipparion Conference. 1981’ Volume I: Methodology, edited by M. Woodburne & P. Sondaar. E. J. Brill. The Hymenoptera, edited by Ian Gauld & Barry Bolton. A Study of Blackbirds, by David Snow Temperature Biology of Animals, by Andrew R. Cossins and Ken Bowler. Honey Identification, by Rex Sawyer. Megaherbivores: The Influence of Very Large Body Size on Ecology, by R. N. Owen-Smith.  相似文献   

16.
In ‘Flora of China’, the combination ‘Gymnosporia graciliramula (S. J. Pei & Y. H. Li) Q. R. Liu & Funston’ was proposed, but this name was not validly published in 2008 because the presumed basionym Maytenus graciliramula S. J. Pei & Y. H. Li was not published in 1979 as stated, but in 1981, contrary to Article 33.4 of ICBN. Meanwhile, two older names, M. thyrsiflora S. J. Pei & Y. H. Li and M. pseudoracemosa S. J. Pei & Y. H. Li, were listed as synonyms in conflict with article 52.3 of ICBN. In this article, we propose a new combination G. thyrsiflora (S. J. Pei & Y. H. Li) W. B. Yu & D. Z. Li that is the correct name when G. thyrsiflora, M. pseudoracemosa and M. graciliramula are treated as a single species in Gymnosporia.  相似文献   

17.
Two genotypes of root‐knot nematode, Meloidogyne arenaria (A2‐O and A2‐J), are found in Japan. They were distinguished from each other based on mitochondrial DNA sequences. The primer set (C2F3/1108) amplified a 1.7‐kb fragment from A2‐J, whereas a 1.1‐kb fragment was amplified from A2‐O. Marenaria (A2‐O) was detected in local regions of southern Japan, whereas M. arenaria (A2‐J) was widespread from the Kyushu region to the Tohoku region. The distribution of M. arenaria (A2‐J) overlaps with the cultivation area of eggplant. Solanum torvum is used worldwide as a rootstock for eggplant cultivation, and it is resistant to Meloidogyne spp. In particular, it is reported that S. torvum is resistant to M. arenaria outside Japan. In this study, we inoculated S. torvum rootstock cultivars with M. arenaria (A2‐J), M. arenaria (A2‐O) and Meloidogyne incognita populations. Although M. incognita and M. arenaria (A2‐O) produced only a few egg masses on S. torvum, thereby confirming its resistance, the four geographical populations of M. arenaria (A2‐J) produced large numbers of egg masses on S. torvum. This study confirmed that S. torvum is resistant to M. incognita and M. arenaria (A2‐O) populations, but susceptible to populations of M. arenaria (A2‐J) in the eggplant production area of Japan.  相似文献   

18.
A C Anusiem  M Kelleher 《Biopolymers》1984,23(7):1147-1167
Interest in the thermodynamics of the iron-binding site in hemoproteins has increased in recent years due to refinements in x-ray crystallographic studies of hemoproteins [see Deathage, J. F., Lee, R. S., Anderson, C. M. & Moffat, K. (1976) J. Mol. Biol. 104 , 687–706; Heidner, E. J., Ladner, R. C. & Perutz, M. F. (1976) J. Mol. Biol. 104 , 707–722; Deathage, J. F., Lee, R. S. & Moffat, K. (1976) J. Mol. Biol. 104 , 723–728; Ladner, R. C., Heidner, E. J. & Perutz, M. F. (1976) J. Mol. Biol. 114 , 385–414; Fermi, G. & Perutz, M. F. (1977) J. Mol. Biol. 114 , 421–431; Takano, T. (1977) J. Mol. Biol. 110 , 537–568 and 569–589], the synthesis and x-ray analysis of model heme compounds [see Scheidt, W. R. (1977) Acc. Chem. Res. 10 , 339–345; Kastner, M. E., Scheidt, W. R., Mashino, T. & Reed, C. A. (1978) J. Am. Chem. Soc. 100 , 666–667; Mashiko, T., Kastner, M. E., Spartalian, K., Scheidt, W. R. & Reed, C. A. (1978) J. Am. Chem. Soc. 100 , 6354–6362; Hill, H. A. O., Skite, P. P., Buchler, J. W., Luchr, H., Tonn, M., Gregson, A. K. & Pellizer, G. (1979) Chem. Commun. 4 , 151–152; and Scheidt, W. R., Cohen, I. A. & Kastner, M. E. (1979) Biochemistry 18 , 3546–3556], and the numerous data on heme–protein interactions that account for the differences observed in ligand binding between the various species of animals. Numerous probes have been used and provide information about the structure and thermodynamics of the binding site, but no single probe can provide the complete picture [see Iizuka, T. & Yonetani, T. (1970) Adv. Biophys. 1 , 157–182; Smith, D. W. & Williams, R. J. P. (1970) Struct. Bond. 7 , 1–45; and Spiro, T. G. (1975) Biochim. Biophys. Acta 416 , 169–189].  相似文献   

19.
Cecropia glazioui Sneth (Cecropiaceae) is used in folk medicine in tropical and subtropical Latin America as cardiotonic, diuretic, hypotensive, anti-inflammatory and anti-asthmatic. The hypotensive/antihypertensive activity of the plant aqueous extract (AE) and isolated butanolic fraction (BuF) has been confirmed and putatively related to calcium channels blockade in vascular smooth musculature [Lapa, A.J., Lima-Landman, M.T.R., Cysneiros, R.M, Borges, A.C.R., Souccar, C., Barreta, I.P., Lima, T.C.M., 1999. The Brazilian folk medicine program to validate medicinal plants – a topic in new antihypertensive drug research. In: Hostettman, K., Gupta, M.P., Marston, A. (Eds.), Proceedings Volume, IOCD/CYTED Symposium, Panamá City, Panamá, 23–26 February 1997. Chemistry, Biological and Pharmacological Properties of Medicinal Plants from the Americas. Harwood Academic Publishers, Amsterdam, pp. 185–196; Lima-Landman, M.T., Borges, A.C., Cysneiros, R.M., De Lima, T.C., Souccar, C., Lapa, A.J., 2007. Antihypertensive effect of a standardized aqueous extract of Cecropia glaziovii Sneth in rats: an in vivo approach to the hypotensive mechanism. Phytomedicine 14, 314–320]. Bronchodilation and antidepressant-like activities of both AE and BuF have been also shown [Delarcina, S., Lima-Landman, M.T., Souccar, C., Cysneiros, R.M., Tanae, M.M., Lapa, A.J., 2007. Inhibition of histamine-induced bronchospasm in guinea pigs treated with Cecropia glaziovi Sneth and correlation with the in vitro activity in tracheal muscles. Phytomedicine 14, 328–332; Rocha, F.F., Lima-Landman, M.T., Souccar, C., Tanae, M.M., De Lima, T.C., Lapa, A.J., 2007. Antidepressant-like effect of Cecropia glazioui Sneth and its constituents – in vivo and in vitro characterization of the underlying mechanism. Phytomedicine 14, 396–402]. This study reports the antiulcer and antisecretory gastric acid activities of the plant AE, its BuF and isolated compounds with the possible mechanism involved. Both AE and BuF were assayed on gastric acid secretion of pylorus-ligated mice, on acute models of gastric mucosal lesions, and on rabbit gastric H+, K+-ATPase preparations. Intraduodenal injection of AE or BuF (0.5–2.0 g/kg, i.d) produced a dose-related decrease of the basal gastric acid secretion in 4-h pylorus-ligated mice. At 1.0 g/kg, BuF decreased the volume (28%) and total acidity (33%) of the basal acid secretion, and reversed the histamine (2.5 mg/kg, s.c.)- or bethanecol (1.0 mg/kg, s.c.)-induced acid secretion to basal values, indicating inhibition of the gastric proton pump. Pretreatment of mice with the BuF (0.05–0.5 g/kg, p.o.) protected against gastric mucosal lesions induced by 75% ethanol, indomethacin (30 mg/kg, s.c.) or restraint at 4 °C. BuF also decreased the gastric H+, K+-ATPase activity in vitro proportionately to the concentration (IC50=58.8 μg/ml). The compounds isolated from BuF, consisting mainly of cathechins, procyanidins and flavonoids [Tanae, M.M., Lima-Landman, M.T.R., De Lima, T.C.M., Souccar, C., Lapa, A.J., 2007. Chemical standardization of the aqueous extract of Cecropia glaziovii Sneth endowed with antihypertensive, bronchodilator, antacid secretion and antidepressant-like activities. Phytomedicine 14, 309–313], inhibited the in vitro gastric H+, K+-ATPase activity at equieffective concentrations to that of BuF. The results indicate that C. glazioui constituents inhibit the gastric proton pump; this effect may account for the effective antisecretory and antiulcer activities of the standardized plant extract.  相似文献   

20.
The genus Metrosideros (Myrtaceae) is an abundant and taxonomically confusing component of the vegetation throughout much of its range. In the southern Pacific, from the New Hebrides eastward to the Society and Tuamotu Islands, the genus is represented by one variable species, M. collina (J. R. & G. Forst.) A. Gray, in which three widespread varieties seem to merit recognition. An attempt is here made to clarify the nomenclature and inter-relationships of these varieties. Additionally, two local endemics are related to the M. collina group—M. gregoryi Christophersen in Samoa and M. ochrantha A. C. Sm. (sp. nov.) in Fiji.  相似文献   

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