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1.
Abstract

This study undertakes a cytogenetic analysis of the New Zealand blackfly species Austrosimulium australense (Schiner). The principles of such an approach are outlined, and previous taxonomic studies of the genus Austrosimulium, in particular the taxonomic position of A. australense, are discussed. Populations from North Island localities covering a wide area were sampled and analysed for polymorphisms in the polytene chromosomes, taken from salivary glands of larvae. In all, 1018 larvae from 49 sites were analysed. A polytene chromosome map of A. australense is presented, with details of chromosomal inversions found in salivary gland cells. Three geographical zones are designated, according to the incidence of certain chromosomal polymorphisms.  相似文献   

2.

The female of Austrosimulium (Austrosimulium) dumbletoni n.sp. is described and compared with other New Zealand species in the subgenus. Females were captured while they were biting caged Fiordland crested penguins, Eudyptes p. pachyrhynchus. They are vectors of the blood parasite Leucocytozoori tawaki.  相似文献   

3.
1. In insects, instar determination is generally based on the frequency distribution of sclerotised body part measurements. Commonly used univariate methods, such as histograms and univariate kernel smoothing, are not sufficient to reflect the distribution of the measurements, because development of sclerotised body parts is multidimensional. 2. This study used an adaptive bivariate kernel smoothing method, based on 10 pairs of separating variables, to differentiate instars of Austrosimulium tillyardianum (Diptera: Simuliidae) larvae in two‐dimensional space. A variable bandwidth matrix was used and separation lines between instars were defined. Using the Crosby growth ratio, Brooks' rule and the new standard recently proposed, larvae were separated into nine instars. It was found that, using the bivariate kernel smoothing method, the clustering accuracy and determination of separation lines as instar class limits were higher than those associated with the univariate kernel smoothing method. With the exceptions of the paired separating variables, head capsule length and antennal segment 3 length (AS3L), the mean probabilities of correct classifications was > 85%. The pair of separating variables that yielded the greatest classification accuracy comprised mandible length (ML) and AS3L, which had mean probabilities of 0.8984. The clustering accuracy was higher for early‐ and late‐instar larvae, but lower for instars 6 and 7. The adaptive bivariate kernel smoothing method was better than univariate methods for instar determination, especially in the detection of divisions between instars and identification of a larval instar.  相似文献   

4.
5.
The food of the larvae of two New Zealand Trichoptera, Hydrobiosis parumbripennis and Hydropsyche colonica, was investigated between March and November 1971 at the Wainui Valley Stream, Canterbury, New Zealand. Most samples were collected from an experimental channel constructed in the stream in 1970. The first three instars of H. parumbripennis were mainly detrital feeders, whereas the two later instars were exclusively carnivorous. In contrast, H. colonica was omnivorous. The main prey taken by H. parumbripennis were larvae of a simuliid, Austrosimulium tillyardianum, Chironomidae (subfamily Orthocladiinae), and an ephemeropteran, Deleatidium sp. The first three instars appeared to select chironomids in preference to simuliids, whereas the converse was true for the final two instars. The main prey taken by H. colonica was A. tillyardianum. The size of prey and the mean number of prey found per larva of H. parumbripennis increased with each instar. Forage ratios indicated that H. parumbripennis were eating A. tillyardianum at the same relative frequency as their abundance in the fauna, but that the chironomids and Deleatidium sp. were being preferentially selected as prey. Cased caddis larvae were avoided as food items, as was the mollusc Potamopyrgus antipodarum. Although H. parumbripennis was the most important predator of A. tillyardianum in the stream, it is considered that it has little effect on the simuliid population.  相似文献   

6.
It is a pleasure to contribute to the special issue published in honor of Vladimir Skulachev, a distinguished scientist who greatly contributes to maintain a high standard of biochemical research in Russia. A more particular reason can be found in his work (Artzabanov, V. Y., Konstantinov, A. A., and Skulachev, V. P. (1978) FEBS Lett., 87, 180–185), where observations anticipating some ideas presented in my article were reported. Cytochrome c oxidase exhibits protonmotive, redox linked allosteric cooperativity. Experimental observations on soluble bovine cytochrome c oxidase are presented showing that oxido-reduction of heme a/CuA and heme a 3/CuB is linked to deprotonation/protonation of two clusters of protolytic groups, A1 and A2, respectively. This cooperative linkage (redox Bohr effect) results in the translocation of 1 H+/oxidase molecule upon oxido-reduction of heme a/CuA and heme a 3/CuB, respectively. Results on liposome-reconstituted oxidase show that upon oxidation of heme a/CuA and heme a 3/CuB protons from A1 and A2 are released in the outer aqueous phase. A1 but not A2 appears to take up protons from the inner aqueous space upon reduction of the respective redox center. A cooperative model is presented in which the A1 and A2 clusters, operating in close sequence, constitute together the gate of the proton pump in cytochrome c oxidase.Translated from Biokhimiya, Vol. 70, No. 2, 2005, pp. 220–230.Original Russian Text Copyright © 2005 by Papa.This revised version was published online in April 2005 with corrections to the post codes.  相似文献   

7.
The venation pattern found in the developing wing and haltere buds of larvae is compared with the adult venation in the Austrosimulium (Austro-simulium) australense group of Simuliidae.  相似文献   

8.

The synthesis and properties of oligonucleotides (ONs) containing 9-(2,3,4-trihydroxybutyl)adenine, A C2 and A C3, are described. The ON containing A C2 involves the 3′ → 4′ and 3′ → 5′ phosphodiester linkages in the strand, whereas that containing A C3 possesses the 3′ → 4′ and 2′ → 5′ phosphodiester linkages. It was found that incorporation of the analogs, A C2 or A C3, into ONs significantly reduces the thermal and thermodynamic stabilities of the ON/DNA duplexes, but does not largely decrease the thermal and thermodynamic stabilities of the ON/RNA duplexes as compared with the case of the ON/DNA duplexes. It was revealed that the base recognition ability of A C2 is greater than that of A C3 in the ON/RNA duplexes.  相似文献   

9.
Two interesting ascomycetes are described as new to Japan:Ascotricha amesii (Xylariaceae), isolated from garden soil in Osaka; andAuxarthron reticulatum, isolated from forest soil in Tokyo. ADicyma anamorph is associated with the former species. (52): Tubaki, K., Tokumasu, S. and Konno, M., Nippon Kingakukai Kaiho38: 249–250. 1997.  相似文献   

10.
Three novel dithiazine compounds in the aroma concentrate from cooked sakuraebi, Sergia lucens Hansen, were isolated. Their structures were confirmed as 4,6-dimethyl-2-propyl-1,3,5-dihydrodithiazine (A), 4-butyl-2,6-dimethyl-1,3,5-dihydrodithiazine (B) and pyrrolidino[1,2-e]4H-2,4-dimethyl-1,3,5-dithiazine (C) by spectroscopic analyses. The same compounds have also been found in the aroma concentrate from cooked krill. These three compounds were newly discovered as food volatiles, and among them, compound C seems to take an important role in the aroma of cooked small shrimp by its strong roasted aroma and its relatively high concentration.  相似文献   

11.
Hybridization among species of A conitum effects their morphology and ecology. In this study the hybridization between the diploid 2n(2x) = 16 ( A . lasiocarpum and A . variegatum) and tetraploid 2n(4x) = 32 ( A . firmum) species was documented in the Tatra Mountains (Western Carpathians) in a small, local population in a semi‐natural site. The hybrid species were: homoploid A . × pawlowskii ( A . lasiocarpum × A . variegatum), and triploid A . × berdaui ( A . firmum × A . variegatum, 2n(3x) = 24). Chloroplast DNA (cpDNA) alleles formed two distinct haplotypes, one typical for the tetraploid and another for diploid lines, shared between the tetraploid, triploid and diploid groups, indicating introgressive hybridization. The presumed gene flow was from the tetraploid to diploid species via the triploid bridge. The only two specimens of A . × pawlowskii that harbored tetraploid ( A . firmum) type cpDNA possessed bracteoles of A . firmum‐type. The remaining introgressed (cpDNA and Inter Simple Sequence Repeats (ISSR)) specimens ( A . variegatum) were morphologically pure, implying cryptic introgression. ISSR loci shared between the tetraploid A . firmum and diploid A . variegatum support the hypothesis of an ancient allopolyploid origin of A . firmum and the diploid species of A . variegatum‐type as one of its parent.  相似文献   

12.
Abstract

A high resolution SSCP protocol was developed for simultaneous discrimination of the known CSN3 alleles A, B, C, E, F and G. Furthermore, three new DNA polymorphisms were identified in different Bos taunts and Bos indicus breeds or crosses. Mendelian segregation was shown for two of these polymorphisms (named CSN3?H and 7), and the third (named CSN3?A1 ) was found in unrelated animals, thus indicating the presence of three additional alleles at the bovine CSN3 locus. DNA sequencing revealed single mutations that led to a Thr/Ile substitution in amino acid position 135 for CSN3 ?H and to a Ser/Ala substitution in position 104 of the deduced amino acid sequence of CSN3 ?I (GenBank accession numbers AF105260 and AF121023) compared to CSN3?A. In CSN3?AI , a silent mutation in the third codon position of PrO150 was found (GenBank accession number AF092513).  相似文献   

13.
A new species, Allium pseudosenescens, belonging to sect. Rhizirideum (Alliaceae), is described from northeastern China. It is easily distinguished from A. senescens by the slender pedicels, pale pink perianths, narrower tepals and ovaries, yellowish anthers, and sometimes toothed subulate filaments. Also, A. senescens var. minus in sect. Rhizirideum is raised to the rank of species, as A. minus. This Korean endemic taxon is shown to be a biologically distinct species based on morphological and cytological characters. Taxonomic keys for the species of Allium sect. Rhizirideum in northeastern China and Korea are provided.  相似文献   

14.
The ferriheme resonances of the low-spin (S = 1/2) complexes of wild-type (wt) nitrophorin 2 (NP2) and its heme pocket mutant NP2(V24E) with imidazole (ImH), histamine (Hm), and cyanide (CN) as the sixth ligand have been investigated by NMR spectroscopy as a function of pH (4.0–7.5). For the three wt NP2 complexes, the ratio of the two possible heme orientational isomers, A and B, remains almost unchanged (ratio of A:B approximately 1:6 to 1:5) over this wide pH range. However, strong chemical exchange cross peaks appear in the nuclear Overhauser effect spectroscopy/exchange spectroscopy (NOESY/EXSY) spectra for the heme methyl resonances at low pH (pH* 4.0–5.5), which indicate chemical exchange between two species. We have shown these to be two different exogenous ImH or Hm orientations that are denoted B and B′, with the ImH plane nearly parallel and perpendicular to the ImH plane of the protein-provided His57, respectively. The wt NP2–CN complex also shows EXSY cross peaks due to chemical exchange, which is shown to be a result of interchange between two ruffling distortions of the heme. The same ruffling distortion interchange is also responsible for the ImH and Hm chemical exchange. For the three NP2(V24E) ligand complexes, no EXSY cross peaks are observed, but the A:B ratios change dramatically with pH. The fact that heme favors the A orientation highly for NP2(V24E) at low pH as compared with wt NP2 is believed to be due to the steric effect of the V24E mutation. The existence of the B′ species at lower pH for wt NP2 complexes and the increase in A heme orientation at lower pH for NP2(V24E) are believed to be a result of a change in structure near Glu53 when it is protonated at low pH. 1H{13C} heteronuclear multiple quantum coherence (HMQC) spectra are very helpful for the assignment of heme and nearby protein side chain resonances.  相似文献   

15.
Purpose: Eight A2AR variants are reported in humans while no A2AR isoforms in pigs. The aim of this study was to evaluate potential isoforms presence in cardiac pig tissue to better define possible involvement of A2AR in the cardiovascular pathophysiology.

Materials and methods: In adult male minipigs (n?=?4) left ventricular dysfunction (LVD) was induced by pacing at 200 bpm in the right ventricular (RV) apex. In these animals and in sham operated pigs (C-SHAM, n?=?4) cardiac tissue was collected from LV-septal wall (LV-SW)-close to pacing site-and from lateral (opposite) site (LV-OSW). A2AR specific primers, derived from Sus scrofa AY772412 sequence, were used for Real-Time PCR. The DNA was sequenced using the Sanger method. Histological analysis was also performed.

Results: In LV-SW of LVD minipigs the A2AR melting curves were characterized by a sharp peak between 87 and 91?°C (short isoform, 1–94?bp) on the right of the principal peak corresponding to a long A2AR isoform (GenBank: JQ229674.1) 1–213?bp. As for C-SHAM only one peak was observed in LV-OSW region of LVD animals. The short isoform had an alternative promoter region and a specific translated protein. Histology showed in LVD-LV-SW prominent Purkinje cells compared to LV-OSW and C-SHAM. No difference in A2AR expression was observed between LVD animals and C-SHAM although a slight decrease was observed in LVD-LV-OSW.

Conclusions: The presence of two different isoforms in the myocardium close to the insertion of pacing is suggestive of a differential state-specific expression of A2AR in cardiac tissue.  相似文献   

16.
The building blocks fac-[99mTc{κ3-HB(timMe)3}(CO)3] and fac-[99mTc{κ3-R(μ-H)B(timMe)2}(CO)3] [R is H (4a), Ph (5a); timMe is 2-mercapto-1-methylimidazolyl] were obtained almost quantitatively by reacting fac-[99mTc(CO)3(H2O)3]+ with the corresponding scorpionate. These compounds cross the intact blood–brain barrier in mice, with significant retention in the case of 4a and 5a. Using 4a as the lead structure, we have synthesized the functionalized complexes fac-[M{κ3-H(μ-H)B(timBu-pip)2}(CO)3] [M is Re (8), 99mTc (8a); timBu-pip is methyl[4-((2-methoxyphenyl)-1-piperazinyl)butyl](2-mercapto-1-methylimidazol-5-yl)methanamide] and fac-[M{κ 3-H(μ-H)B(timMe)(timBu-pip)}(CO)3] [M is Re (9), 99mTc (9a)] and evaluated their potential as radioactive probes for the targeting of brain 5-HT1A serotonergic receptors. The Re complexes exhibit excellent affinity [IC50=0.172 ± 0.003 nM (8); IC50=0.65 ± 0.01 nM (9)] for the 5-HT1A receptor. The radioactive congeners (99mTc) have shown an initial brain uptake of 1.38 ± 0.46%ID g−1 (8a) and 0.43 ± 0.12%ID g−1 (9a), but suffer from a relatively fast washout.  相似文献   

17.
The species Anomala aereiventris n. sp., A. aspersa n. sp., A. atrivillosa n. sp., A. clarivillosa n. sp., A. contusa n. sp., A. eusticta n. sp., A. hiata n. sp., A. latifalculata n. sp., A. leopardina n. sp., A. levicollis n. sp., A. longisacculata n. sp., A. m-fuscum n. sp., A. perspicax n. sp., A. piccolina n. sp., A. globulata n. sp., A. stillaticia n. sp., A. subridens n. sp., A. subusta n. sp., A. tenoriensis n. sp., A. tuberculata n. sp. and A. vallisneria n. sp. from Costa Rica are described. These species and A. polygona Bates 1888, A. trapezifera Bates 1888 and A. vulcanicola Ohaus 1897 are placed in a new species-group, named after A. trapezifera, whose diagnosis is provided. Their distribution patterns are discussed.  相似文献   

18.
The karyotypes of 47 hybrid lines obtained from crosses of common wheat Triticum aestivum L. (cv. Rodina and line 353) with Triticum timopheevii(Zhuk.) Zhuk. (A t A t GG) and related species T. militinae Zhuk. et Migusch. (A t A t GG) and T. kiharae Dorof. et Migusch. (A t A t GGD sq D sq) were analyzed by C-banding. Most lines were resistant to yellow rust and powdery mildew. The introgression of alien genetic material to the common wheat genome was realized via substitutions of complete A +-,G-, and D-genome chromosomes, chromosome arms, or their fragments. The pattern of chromosome substitutions in resistant lines differed from that in introgressive hybrids selected for other traits. Substitutions of chromosomes 6G, 2At, 2G, and 5G were revealed in 31, 23, 18, and 13 lines, respectively. Substitutions of chromosomes 4G, 4At, and 6At were not observed. In 15 lines, a 5BS.5BL-5GL translocation was identified. High frequency of substitutions of chromosomes 2At, 2G, 5G, and 6G indicate that they may carry the resistance genes and that they are closely related to the respective homoeologous chromosomes of common wheat that determines their high compensation ability.  相似文献   

19.
 An approach is presented which probes the possible use of trans-[(NH3)2PtCl]+-modified deoxyoligonucleotides in the antisense strategy. It consists of (1) the selective platination of an oligonucleotide containing 11 pyrimidine (T, C) bases as well as a single guanine (G) as a Pt-anchoring group at the 5′-end to give trans-[(NH3)2Pt{5′-d(GN7T2C2T2C2T2C}Cl]10– 1 ("antisense strand") and (2) subsequent hybridization with the purine 12-mer 5′-d(GA2G2A2G2A2G)11– ("sense strand"). According to HPLC, three major species 24 are formed during reaction (2), all of which are cross-linking adducts between 1 and the sense strand, as confirmed by ESI MS and melting temperature measurements. Only for the major product 3 can a structure be proposed on the basis of 1D and 2D NMR spectra. According to these, G1 of the antisense strand is cross-linked with G20 via trans-(NH3)2PtII. The complementary overhangs of the duplex represent "sticky ends" and are, in principle, capable of associating into multimers of the duplex. Received: 29 March 1999 / Accepted: 26 July 1999  相似文献   

20.
(+)-Marmelo oxide A and (—)-marmelo oxide B were stereoselectively synthesized from d-glutamic acid via (—)-marmelo lactones A and B. The absolute configurations of marmleo oxides were thus determined to be the (+)-oxide A having the (2R, 4R) and (+)-oxide B having (2S, 4R) configurations.  相似文献   

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