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1.
In order to investigate the relationship existing between the electronic structures of collagen and its biochemical functions in vivo, the semiempirical CNDO/2 SCF MO calculations were carried out on several model polymers of collagen, (Gly-Pro)n, (Gly-Hyp)n, (Ala-Pro)n, (Ala-Hyp)n, (Gly-Pro-Gly)n, (Gly-Hyp-Gly)n, (Gly-Pro-Pro)n and (Gly-Pro-Hyp)n. Geometries of the skeleton of these polymers were assumed to be the same as those of poly(l-proline) I (cis) and II (trans) and the calculations were performed only on infinite polymers in a single chain. The results show that the cis form is always more stable than the trans form for all the polymers treated. This energy difference between the cis and trans forms depends, for example, on the kind of amino acid residue, Gly or Ala, but this could not be seen in the Pro or Hyp residue. The flexibility or mobility of the collagen structure was explained using the energy difference between the cis and trans forms of the polymers, i.e. the cis-trans conversion of the collagen was discussed in connection with the energy difference. The reason why the collagen has the constitution of (Gly-Pro-Hyp)n is briefly discussed.  相似文献   

2.
Data on natural enemies of psyllids are rare and can usually be found in papers about economically significant species. During an investigation of psyllid fauna in Serbia, natural enemies were investigated, too. True bugs were the most numerous among them. From 28 psyllid species, 21 species of true bugs from families Anthocoridae and Miridae were reared. Seven species of Anthocoridae were identified: Anthocoris amplicollis (Horváth, 1839), Anthocoris confusus Reuter, 1884, Anthocoris nemoralis (Fabricius, 1794), Anthocoris nemorum (Linnaeus, 1761), Orius majusculus Reuter, 1884, Orius minutus (Linnaeus, 1758) and Orius niger Wolff, 1811. The following 14 species of Miridae were identified: Atractotomus mali Meyer-Dür, 1843, Campylomma verbasci (Meyer-Dür, 1843), Deraeocoris flavilinea (A. Costa, 1862), Deraeocoris ruber (Linnaeus, 1758), Deraeocoris lutescens (Schilling, 1836), Heterocordylus genistae (Scopoli, 1763), Hypseloecus visci (Puton, 1888), Malacocoris chlorizans Panzer, 1794, Miris striatus (Linnaeus, 1758), Orthotylus marginalis Reuter, 1884, Psallus assimilis Stichel, 1956, Psallus quercus Kirschbaum, 1856, Psallus flavellus Stichel, 1933 and Pseudoloxops coccinea (Meyer-Dür, 1843). The aim of the research was to provide list of true bugs recorded as predators of psyllids in order to preserve their diversity and significance, especially on cultivated plants.  相似文献   

3.
A short review of main cytogenetic features of insects belonging to the sister neuropteran families Myrmeleontidae (antlions) and Ascalaphidae (owlflies) is presented, with a particular focus on their chromosome numbers and sex chromosome systems. Diploid male chromosome numbers are listed for 37 species, 21 genera from 9 subfamilies of the antlions as well as for seven species and five genera of the owlfly subfamily Ascalaphinae. The list includes data on five species whose karyotypes were studied in the present work. It is shown here that antlions and owlflies share a simple sex chromosome system XY/XX; a similar range of chromosome numbers, 2n = 14-26 and 2n = 18-22 respectively; and a peculiar distant pairing of sex chromosomes in male meiosis. Usually the karyotype is particularly stable within a genus but there are some exceptions in both families (in the genera Palpares and Libelloides respectively). The Myrmeleontidae and Ascalaphidae differ in their modal chromosome numbers. Most antlions exhibit 2n = 14 and 16, and Palparinae are the only subfamily characterized by higher numbers, 2n = 22, 24, and 26. The higher numbers, 2n = 20 and 22, are also found in owlflies. Since the Palparinae represent a basal phylogenetic lineage of the Myrmeleontidae, it is hypothesized that higher chromosome numbers are ancestral for antlions and were inherited from the common ancestor of Myrmeleontidae + Ascalaphidae. They were preserved in the Palparinae (Myrmeleontidae), but changed via chromosomal fusions toward lower numbers in other subfamilies.  相似文献   

4.
Secoisolariciresinol diglucosides (SDGs) (S,S)-SDG-1 (major isomer in flaxseed) and (R,R)-SDG-2 (minor isomer in flaxseed) were synthesized from vanillin via secoisolariciresinol (6) and glucosyl donor 7 through a concise route that involved chromatographic separation of diastereomeric diglucoside derivatives (S,S)-8 and (R,R)-9. Synthetic (S,S)-SDG-1 and (R,R)-SDG-2 exhibited potent antioxidant properties (EC50 = 292.17 ± 27.71 μM and 331.94 ± 21.21 μM, respectively), which compared well with that of natural (S,S)-SDG-1 (EC50 = 275.24 ± 13.15 μM). These values are significantly lower than those of ascorbic acid (EC50 = 1129.32 ± 88.79 μM) and α-tocopherol (EC50 = 944.62 ± 148.00 μM). Compounds (S,S)-SDG-1 and (R,R)-SDG-2 also demonstrated powerful scavenging activities against hydroxyl [natural (S,S)-SDG-1: 3.68 ± 0.27; synthetic (S,S)-SDG-1: 2.09 ± 0.16; synthetic (R,R)-SDG-2: 1.96 ± 0.27], peroxyl [natural (S,S)-SDG-1: 2.55 ± 0.11; synthetic (S,S)-SDG-1: 2.20 ± 0.10; synthetic (R,R)-SDG-2: 3.03 ± 0.04] and DPPH [natural (S,S)-SDG-1: EC50 = 83.94 ± 2.80 μM; synthetic (S,S)-SDG-1: EC50 = 157.54 ± 21.30 μM; synthetic (R,R)-SDG-2: EC50 = 123.63 ± 8.67 μM] radicals. These results confirm previous studies with naturally occurring (S,S)-SDG-1 and establish both (S,S)-SDG-1 and (R,R)-SDG-2 as potent antioxidants and free radical scavengers for potential in vivo use.  相似文献   

5.
Oecetis tripunctata is a widely distributed leptocerid in Europe, ranging from the Iberian and Apennine peninsulas and the Central and Western European highlands to the plains of Eastern Europe. The long, single-bladed mandibles are indicative for a predacious lifestyle. This paper describes the previously unknown larva of Oecetis tripunctata. Information on the morphology of the 5th larval instar is given, and the most important diagnostic features are illustrated. A synoptic key for the European species of Oecetis is also provided. In the context of existing identification keys the larva of Oecetis tripunctata keys together with Oecetis intima and Oecetis notata. Oecetis tripunctata is separated from the other two species by the fact that a double row of long setal fringes is lacking at the hind tibiae and that several long setae are present on the protrochantinus.  相似文献   

6.
The Tribe Hemilophini (Lamiinae) is reviewed for Hispaniola and an identification key is provided. Fifteen species are now known from the island, including one new species of Adesmus (Adesmus fortunei from Pedernales and La Vega Provinces, Dominican Republic), one new species of Oedudes (Oedudes anulatus from Peravia and La Vega Provinces, Dominican Republic), and five new species of Calocosmus (Calocosmus contortus from San Cristóbal Province, Calocosmus punctatus from Peravia Province, Calocosmus rawlinsi from Elías Piña Province, Calocosmus robustus from La Vega Province, and Calocosmus thonalmus from La Altagracia Province, all in the Dominican Republic). Oedudes and Adesmus are new island and country records for Hispaniola and Dominican Republic, respectively. Calocosmus holosericeus Gahan is a new synonym of Calocosmus janus Bates. In addition to the new species, five new country records and four new island records are presented for Calocosmus.  相似文献   

7.
The Lacinipolia vicina (Grote) species complex, previously consisting of Lacinipolia vicina, Lacinipolia teligera (Morrison), Lacinipolia pensilis (Grote), and Lacinipolia subalba Mustelin is revised to six species: Lacinipolia vicina (eastern USA), Lacinipolia teligera (southern Great Plains), Lacinipolia pensilis (Pacific Northwest and northern Rocky Mountains), Lacinipolia acutipennis (Grote), stat. rev. (= Lacinipolia subalba syn. n.) (western North America), Lacinipolia sareta (Smith), stat. rev. (Canada and western USA) and Lacinipolia dimocki, sp. n. (California and Pacific Northwest). Lectotypes are designated for Lacinipolia vicina, Lacinipolia teligera and Lacinipolia pensilis.  相似文献   

8.
9.
Five species of the subgenus Galumna (Galumna) (Acari, Oribatida, Galumnidae) are registered in the Philippine oribatid mite fauna. A new species, Galumna (Galumna) makilingensis sp. n., is described; it is most similar morphologically to Galumna (Galumna) tokyoensis Aoki, 1966, but differs from the latter by the morphology of porose areas Aa and Ap, rostral setae, and length of interlamellar setae. Three species, Galumna (Galumna) crenata Deb & Raychaudhuri, 1975, Galumna (Galumna) cf. exigua Sellnick, 1925 and Galumna (Galumna) khoii Mahunka, 1989, are recorded in the Philippines for the first time. The species Galumna (Galumna) crenata is redescribed. An identification key to the Philippine species of Galumna (Galumna) is given.  相似文献   

10.
A revision of the surviving “Barroisiceras” specimens from Cameroon described by SOLGER (1904) suggests thatBarroisiceras brancoi, type species ofSolgerites REESIDE, 1932, including varietiesmitis andarmatus of SOLGER, andBarroisiceras hoberfellneri alstadenensis SOLGER non SCHLüTER are variants of a single species and thatSolgerites is a synonym ofForresteria (Forresteria) REESIDE, 1932, of whichEboroceras BASSE, 1947 also is a synonym.  相似文献   

11.
A new species, Cherax (Astaconephrops) pulcher sp. n., from Hoa Creek, close to the village Teminabuan in the southern-central part of the Kepala Burung (Vogelkop) Peninsula, West Papua, Indonesia, is described, figured and compared with the morphologically closest species, Cherax boesemani Lukhaup & Pekny, 2008.  相似文献   

12.
Jen? Kontschán 《ZooKeys》2014,(447):35-45
Three new species of the family Rotundabaloghiidae are discovered and described from Sabah, Malaysia. The unusual Angulobaloghia rutra sp. n. differs from the other known Angulobaloghia Hirschmann, 1979 species in the long anterior process of the female’s genital shield. Rotundabaloghia (Circobaloghia) tobiasi sp. n. has very long and apically pilose dorsal setae and two pairs of bulbiform setae, which are unique in the subgenus Rotundabaloghia (Circobaloghia) Hirschmann, 1975. The long, serrate and curved setae in the big ventral cavity of Depressorotunda (Depressorotunda) serrata sp. n. is a so far unknown character in the subgenus Depressorotunda (Depressorotunda) Kontschán, 2010.  相似文献   

13.
The oegopsid squids Abraliopsis and Pterygioteuthis are abundant and diverse genera with taxonomic and distributional problems. Identification and distribution of species in the Mexican Pacific has been somewhat controversial. Here are provided a large series of new records for Abraliopsis affinis, Abraliopsis falco, Pterygioteuthis gemmata, Pterygioteuthis giardi and Pterygioteuthis hoylei from the Gulf of California and off the SW coast of Mexico. All five species were collected in the central or the southern Gulf of California, or in both. Abraliopsis affinis was found in seven samples with a total of 48 specimens, from 21°59'' to 24°53''12"N. Abraliopsis falco was much less represented in the samples (14 specimens) but it was found in 10 localities, four of which correspond to the central-southern Gulf of California (north to 27°44''53"N) and six to SW Mexico (south to 16°49''18"N). In the case of Pterygioteuthis gemmata, only two records (three specimens) were obtained, both in the SW Gulf of California, while Pterygioteuthis giardi (nine specimens) records were all from the central Gulf of California (27°44''53” to 25°39''59"N). In the case of Pterygioteuthis hoylei (nine specimens), material was obtained in six localities, also in a restricted latitudinal range (24°23''48” to 25°56''56"N).  相似文献   

14.
Ostracod association from the Upper Triassic (Tropites dilleri zone of the Carnian stage) of the sedimentary succession (Mufara Formation) exposed along the east side of Monte Scalpello (Catenanuova, central eastern Sicily) has been studied for the first time. The specimens, silicified, are rare but well preserved and often consist of complete carapaces. They belong to eight families: Healdiidae, Cavellinidae, Bairdiidae, Acratiidae, Bythocyprididae, Pontocyprididae, Judahellidae, Glorianellidae. Twenty-three taxa have been listed; the family Bairdiidae is the most represented among all the others with fifteen species. Four species are new: Bairdia scaliae n. sp., Acratia maugerii n. sp., “Anchistrocheles” gemmellaroi n. sp. and Judahella? montanarii n. sp. Other species are left in open nomenclature because of the lack of specimens.  相似文献   

15.
The following species are described, figured and/or recorded from pomacentrid fishes from the vicinity of the southern Great Barrier Reef coral cay Heron Island, with some mention of comparative material from other host families and locations: Derogenes pearsoni n. sp. from Amblyglyphidodon curacao, Amphiprion akindynos, Plectroglyphidodon lacrymatus (type-host), Pomacentrus chrysurus, P. moluccensis, P. tripunctatus and Pomacentrus sp.; Derogenes pharyngicola n. sp. from Abudefduf whitleyi (type-host) and Plectroglyphidodon dickii; Lecithaster stellatus from Abudefduf sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amblyglyphidodon curacao, Chrysiptera flavipinnis, Parma polylepis, Pomacentrus chrysurus, P. moluccensis, P. cf. nagasakiensis, P. cf. pavo, P. vaiuli, P. wardi, Seriola lalandi, Cheilinus diagrammus, Lethrinus miniatus and Choerodon cyanodus from Heron Island plus Acanthopagrus australis and Rhabdosargus sarba from Moreton Bay; Aponurus laguncula from Pomacentrus moluccensis plus Callionymus limiceps, Platycephalus endrachtensis and P. fuscus from Moreton Bay; Hysterolecitha nahaensis from Abudefduf bengalensis, A. sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amblyglyphidodon curacao, A. leucogaster, Amphiprion akindynos, A. perideraion, Chromis atripectoralis, C. nitida, C. viridis, Chrysiptera flavipinnis, C. cf. rollandi, Dascyllus aruanus, D. reticulatus, Parma polylepis, Pomacentrus chrysurus, P. moluccensis, P. cf. nagasakiensis, P. nigromarginatus, P. cf. pavo, P. tripunctatus, P. wardi and Pomacentrus sp.; Hysterolecitha heronensis n. sp. from Pomacentrus philippinus (type-host), P. amboinensis, P. moluccensis, P. nigromarginatus and Pomacentrus sp.; Hysterolecitha sp. innom. from Parma polylepis; Thulinia microrchis n. comb. (new syns Hysterolecitha microrchis, H. xesuri, H. tinkeri, Thulinia tinkeri, H. sigani) from Abudefduf bengalensis, A. sexfasciatus, A. whitleyi, Acanthochromis polyacanthus, Amphiprion perideraion, Dascyllus aruanus, D. reticulatus, Dischistodus melanotus, Parma polylepis, Plectroglyphidodon dickii, Pomacentrus amboinensis, P. moluccensis, P. philippinus, P. taeniometopon, Pomacentrus sp. and Stegastes apicalis, plus Chaetodon citrinellus, C. kleinii, Chaetodontoplus meredithi, Lethrinus miniatus, Plectropomus leopardus, Siganus doliatus, S. lineatus and S. vulpinus; Leclthocladium sp. juv from Abudefduf whitleyi, Lecithochirium sp. (? ghanense-group) from Dascyllus aruanus; Lecithochirium sp. juv. from Abudefduf whitleyi; unidentified non-ecsomate hemiuroids from Chrysiptera cf. rollandi, Parma polylepis, Pomacentrus chrysurus, P. wardi and Stegastes apicalis.  相似文献   

16.
Sarcophaga (Sarcorohdendorfia) gracilior (Chen, 1975) is documented from specimens collected in Hubei Province, China, using morphological characters and wing interference patterns (WIPs). The female of S. (S.) gracilior is described for the first time, the male is redescribed, and both sexes are photographed. The distribution of the species is updated.  相似文献   

17.
18.
A bisexual population of Potamocypris villosa, found in Lago de Encina, a mesotrophic lake in the Cantabrian mountains, NW Spain, is the first certain record of the male of this species. Valves and soft parts are described. Males of Potamocypris-species lack a furca although a rudimentary furca is always present in females. The same applies to species of related genera, such as Tanganyikacypridopsis and Plesiocypridopsis. Some remarks on the position of the genus Potamocypris in the Cyprinopsinae are presented.  相似文献   

19.
Species of Laccaria are described from the eastern Himalayas, in the Xizang Autonomous Region of China, more commonly known as Tibet. Specimens were collected during several expeditions over a 12-year time span. Nuclear ribosomal internally transcribed spacer regions 1 and 2 including and 5.8S (ITS) as well as the 5' end of the large subunit (28S) sequence data were generated for 22 specimens from Tibet and analyzed in a dataset of 115 Laccaria samples. The results documented seven species from this region, five of which represent currently undescribed species. The taxonomy of Tibetan Laccaria is discussed, five new species are proposed, and an artificial key that includes extralimital species from Asia is provided.  相似文献   

20.
The life-cycle of Echinostoma revolutum (Froelich, 1802) Dietz, 1909 has been completed experimentally beginning with infected snails collected at the type-locality, near Erlangen, Germany. Based on the specimens obtained, each stage of the life-cycle has been redescribed. Important taxonomic features are discussed and hitherto unknown characteristics are described. Synonyms for E. revolutum are: Fasciola revoluta Froelich, 1802; Echinostoma paraulum Dietz, 1909; E. audyi Lie & Umathevy, 1965; and E. ivaniosi Mohandas, 1973. Adults and larvae described as E. revolutum in other works are found to be identical with Echinostoma echinatum (Zeder, 1803), E. trivolvis (Cort, 1914), E. jurini (Skvortsov, 1924), E. caproni Richard, 1964, Moliniella anceps (Molin, 1859), Echinochasmus beleocephalus (Linstow, 1873) and other echinostome species. For nearly a century, incorrect morphological, biological, life-cycle and host information has been attributed to E. revolutum, and at times these data have contributed to the diagnoses of the species. Occasionally, authors actually working with E. revolutum have ascribed their results to other species. Based on extensive experimental life-cycle studies beginning with infected snails from type-localities, it is shown that (1) the first intermediate host is a lymnaeid snail; (2) the second intermediate hosts are various pulmonate and prosobranch snails, mussels, frogs and freshwater turtles; (3) the final hosts are birds; (4) E. revolutum cercariae and adults have 37 collar spines; (5) the species occurs only in Europe and Asia; (6) Cercaria echinata Siebold, 1937, Echinostoma echinatum (Zeder, 1803) and E. jurini (Skvortsov, 1924) are the closely related 37-spined allies in Europe; and (7) species specific characteristics are expressed only in the larvae and the host-parasite relationships. The adults of E. revolutum cannot be identified using morphological criteria and it is proposed that worms with 37 collar spines belonging to the genus Echinostoma and occurring in naturally infected birds in Europe and Asia be referred to an “E. revolutum group.”  相似文献   

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