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1.
Abstract

Three species of anglerfish, Histrio histrio, Antennarius ocellatus, and A. nummifer, are newly recorded from northern New Zealand waters. A. tridens is redescribed, and variations in its colour pattern are illustrated.  相似文献   

2.
Summary Syntheses are described of new endomorphin 1 and 2 peptoid–peptide hybrids in which Tyr1 and either one or both Phe3 and Phe4 have been replaced by N-substituted-glycine. The preparation is also described of two glycosylated Hyp2-endomorphin 2 analogues in which either 2,3,4,6-tetra-O-acetyl glucose or glucose are β-O-glycosidically linked to the hydroxyproline residue. The Hyp2-endomorphin sequences have also been elongate by adding a C-terminal β-alanine residue and several linear dimers have been prepared by coupling either the native peptides or the modified analogues. The cyclo endomorphin 2 has also been synthesized. Preliminary pharmacological experiments on isolated organ preparations showed that the agonist activities of both endomorphin 1 and 2 are not significantly affected by the Pro/Hyp substitution. Phe4/Nphe substitution in the endomorphin 1 reduced the potency on guinea pig ileum (GPI) by about 100 times and abolished the agonist activity on mouse vas deferens (MVD) preparation. The decrease of the agonist activity induced by modification of one phenylalanine residue only, either Phe3 or Phe4, is lower on endomorphin 2. Either modification of both Phe3 and Phe4 or glycosylation of the Hyp2-endomorphin 2 cancelled any agonist activity on both preparations. The linear peptide dimers [endomorphin 1]2, [endomorphin 2]2, [Hyp2-endomorphin 1]2, [Hyp2-endomorphin 2]2, [Hyp2-endomorphin 1-Hyp2-endomorphin 2]2 or [Hyp2-endomorphin 2-Hyp2-endomorphin 1]2, are 7–19 times less potent than endomorphin 1 on GPI and significantly less active than endomorphins 1 and 2 on MVD. The other afforded modifications significantly affected or abolished the agonist activity of the resulting endomorphin analogues on both GPI and MVD preparations.The α-amino acid residues are of the L-configuration. Standard abbreviations for amino acid derivatives and peptides are according to the suggestions of the IUPAC-IUB Commission on Biochemical Nomenclature (1984) Eur. J. Biochem., 138, 9–37. Abbreviations listed in the guide published in (2003) J. Peptide Sci., 9, 1–8 are used without explanation.  相似文献   

3.
W. John Kress 《Brittonia》1991,43(4):253-260
Three new species (Heliconia fredberryana H. litana, andH. lutheri) and one new subspecies (H. obscura ssp.dichroma) from Ecuador are described, illustrated, and discussed.  相似文献   

4.
Eight new Ericaceae (Vaccinieae) from Bolivia and Peru are described, illustrated, and discussed: Orthaea madidiensis, Themistoclesia geniculata, Themistoclesia idiocalyx, Themistoclesia siranensis, Themistoclesia tunquiniensis, Themistoclesia woytkowskii, Thibaudia acacioides, and Thibaudia yungensis.  相似文献   

5.
Seven new triterpene glycosides, erylosides R1 (1), T1 (3), T2 (4), T3 (5), T4 (6), T5 (7), and T6 (8) along with the known formoside (2) were isolated from the sponge Erylus formosus collected along the Caribbean coast of Mexico. Glycoside 1 was determined as a trisaccharide, glycoside 2 as a tetrasaccharide while glycosides 38 were hexasaccharide. Their carbohydrate chains were unprecedented and have never been found in oligosaccharides from other biological sources, except Erylus spp. Three carbohydrate chains in the glycosides 3 and 6, 4 and 7, 5 and 8 correspondingly are new. The glycosides 15 have penasterol as aglycone while glycosides 68 proved to be glycoconjugates of 24-methylene-14-carboxy-lanost-8(9)-en-3β-ol.  相似文献   

6.
Abstract

Seven new taxa of marine mites (Halacaridae) are described from the marine littoral zone of northern and southern New Zealand: Agauopsis novaezelandiae, A. luxtoni, Halacarellus lubricus, Copidognathus lubricus, Simognathus glaber, S. glareus, and Rhombognathus novaezelandicus. A list of halacarid species known from New Zealand waters is added.  相似文献   

7.
New Ceratopogonidae from the Early Cretaceous amber of Hammana (Central Lebanon) are studied. Five new species (Lebanoculicoides daheri sp. nov., Protoculicoides krzeminskii sp. nov., Archiaustroconops annae sp. nov., Archiaustroconops hammanensis sp. nov., and Archiaustroconops dominiakae sp. nov.) are characterized, described, illustrated, and compared with other Cretaceous taxa. New keys for species of the three genera Lebanoculioides, Protoculicoides, and Archiaustroconops, but also for all genera of Lebanese fossil biting midges, are proposed.  相似文献   

8.
The following new species of Apioninae weevils (Coleoptera: Brentidae) are described from Dominican amber. Toxorhynchus leptorhinusn. sp., Toxorhynchus robustusn. sp., Toxorhynchus amphioculusn. sp., Toxorhynchus atriartusn. sp., Toxorhynchusatriantenusn. sp. and Toxorhynchus hispaniolicusn. sp. are members of the Toxorhynchus decoloratum species group. Toxorhynchus microsomusn. sp., Toxorhynchus stenelytrusn. sp., Toxorhynchus dominicanusn. sp., Toxorhynchus convexusn. sp., Toxorhynchus fuscocorpusn. sp., Toxorhynchus hispidulusn. sp. and Toxorhynchus convexoculusn. sp. are members of the Toxorhynchus sordidum species group. A new subtribe, Stenapiina n. subtribe of the tribe Toxorhynchini, is erected. New species Apionion homochrononn. sp.,Apionion kallimosumn. sp.,Apionion formoculusn. sp. and Stenapion levigatumn. sp. are described. The dominate species of the genus Toxorhynchus and especially those in the Toxorhynchus decoloratum and Toxorhynchus sordidum species groups in Dominican amber are now absent from the West Indies. A systematic update of extant representatives of Apioninae in Hispaniola is provided.http://www.zoobank.org/urn:lsid:zoobank.org:pub:2D4A59DB-E804-4B45-8773-C027A8AD5A02  相似文献   

9.
The in vivo and in vitro antiandrogenic activity of four new progesterone derivatives: 4-bromo-17α-(p-fluorobenzoyloxy)-4-pregnene-3,20-dione 1,4-bromo-17α-(p-chlorobenzoyloxy)-4-pregnene-3,20-dione 2, 4-bromo-17α-(p-bromobenzoyloxy)-4-pregnene-3,20-dione 3 and 4-bromo-17α-(p-toluoyloxy)-4-pregnene-3, 20-dione 4 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster prostate and reduced the weight of the prostate glands in gonadectomized hamsters treated with testosterone 5 (T) or dihydrotestosterone 6 (DHT) in a similar manner to that of commercially available finasteride, thus indicating a potent in vivo effect. The in vitro studies showed that steroids 14 have a weak inhibitory activity on 5α-reductase with IC50 values of: 280 (1), 2.6 (2), 1.6 (3) and 114?μM (4). The presence of Cl and Br atoms in the C-17 benzoyloxy group tends to increase the inhibitory potency of the compounds.

The binding efficiency of the synthesized steroids 14 to the androgen receptor of the prostate gland is also evaluated. All compounds form a complex with the receptor and this explains the weight reduction of the seminal vesicles in the animals treated with DHT plus steroids 14.  相似文献   

10.
Efficient syntheses of 14H-dinaphtho[1,8-bc:1′,8′-fg]oxocin-14-one (2), 14H-dinaphtho[1,8-bc:1′,2′-f]oxepin-14-one (3), and 2,2′(2H,2′H)-spirobi[naphtho[1,8-bc]furan] (9) are described. The putative structure of 2 has been reported previously, but the synthetic route was not reproducible. 7H-Dibenzo[c,h]xanthen-7-one (4), a known compound, was obtained by a different method. Possible reaction mechanism are proposed.  相似文献   

11.
Eight new species from Brazil,Ficus acreana,F. bahiensis, F. duartei, F. duckeana, F. hatschbachii, F. lagoensis, F. laureola, andF. rupicola, are described and illustrated. The new species are compared with other species of the genus.  相似文献   

12.
Abstract

Bill Beckley with David Shapiro, eds. Uncontrollable Beauty Allworth Press and the School of Visual Arts 423 pp. $19.95

Venus in Exile: The Rejection of Beauty in Twentieth-Century Art Wendy Steiner The Free Press 280 pp. $26.00  相似文献   

13.
Two new genera and fi ve new species of the psychopsoid Neuroptera (one of which is unnamed) are described from the Early Cretaceous locality at Baissa, Transbaikalia, Russia: Epipsychopsis fusca n. gen., n. sp., E. variegata n. sp. (Psychopsidae), Pseudopsychopsis gradata n. gen., n. sp., P. baissensis n. sp. (Brongniartiellidae), and Sophogramma sp. (Kalligrammatidae).  相似文献   

14.
A total of 10 steroidal glycosides, together with three new spirostanol glycosides (68), a new furostanol glycoside (9), and a new cholestane glycoside (10), were isolated from the rhizomes of Clintonia udensis (Liliaceae). The structures of the new compounds were determined on the basis of extensive spectroscopic analyses, including 2-D nuclear magnetic resonance (NMR) data, and of hydrolytic cleavage followed by chromatographic or spectroscopic analyses. The isolated glycosides were evaluated for their cytotoxic activity against HL-60 leukemia cells. Spirostanol glycosides 1 and 2, and furostanol glycoside 4 showed cytotoxic activity with IC50 values of 3.2±0.02, 2.2±0.12, and 2.2±0.06 μg/ml, respectively. Neither the spirostanol and furostanol saponins with a hydroxy group at C-1 (6 and 9) and C-12 (7 and 8) nor cholestane glycosides (5 and 10) exhibited apparent cytotoxic activity at a sample concentration of 10 μg/ml.  相似文献   

15.
Abstract

Margaret Jane Wyszomirski and Pat Clubb, eds. The Cost of Culture: Patterns and Prospects of Private Arts Patronage. New York: ACA Books, American Council for the Arts, 1989. 97 pages. $9.95 paperback.

Neil Postman. Conscientious Objections: Stirring Up Trouble about Language, Technology, and Education. New York: Alfred A. Knopf, 1988. 190 pages. $17.95 hardback.

The Challenge of Change: Papers and Presentations from the 15th Annual National Conference, ed. Keens Company. New York: FEDAPT, 1987. 144 pages. $14.95 paperback.  相似文献   

16.
17.
Abstract

Isolation and structural determinations of iridoid glucosides from Tecoma arequipensis (Sprague) Sandw. and Skytanthus acutus Meyen are reported. The two species are characterized by the co-occurrence of iridoid glucosides and monoterpene alkaloids.  相似文献   

18.
Four new species are described and illustrated:Coussapoa fulvescens, C. tolimensis, andC. valaria from Colombia, andPourouma napoensis from Ecuador.  相似文献   

19.
Abstract

New genera Isothraulus, Arachnocolus, and Penniketellus are established for three species of leptophlebiid mayfly from New Zealand. Each genus is monotypic and endemic to New Zealand. Isothraulus and Arachnocolus are known only from the northern North Island, and Penniketellus is known only from the Arthur's Pass area of the central South Island. The male and female imago, nymph, and egg of Isothraulus abditus n.sp., the male imago, male subimago, and nymph of Arachnocolus phillipsi n.sp., and the male and female imago, female subimago, and egg of Penniketellus insolitus n.sp. are described. The relationships of each genus and the ecology of nymphs of each species are discussed.  相似文献   

20.
We describe 11 new pteridophyte species belonging to various families from Bolivia: Dennstaedtiaceae:Hypolepis, scandens, Hypolepis minima; Pteridaceae:Cheilanthes glutinosa, Eriosorus angustus, E. ascendens, E. madidiensis; Tectariaceae:Tectaria jimenezii; and Woodsiaceae:Athyrium latinervatum. Diplazium bipinnatum, D. bolivianum, D. yuyoense. The following new combinations are proposed:Anemia australis, Diplazium andicola, D. andinum, andD. petiolulatum.Polystichum maximum is proposed as a new name forPolystichum giganteum.  相似文献   

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