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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   
2.
A study of bacterial surface oligosaccharides were investigated among different strains of Neisseria gonorrhoeae to correlate structural features essential for binding to the MAb 2C7. This epitope is widely expressed and conserved in gonococcal isolates, characteristics essential to an effective candidate vaccine antigen. Sample lipooligosaccharides (LOS), was prepared by a modification of the hot phenol-water method from which de-O-acetylated LOS and oligosaccharide (OS) components were analyzed by ES-MS-CID-MS and ES-MSnin a triple quadrupole and an ion trap mass spectrometer, respectively. Previously documented natural heterogeneity was apparent from both LOS and OS preparations which was admixed with fragments induced by hydrazine and mild acid treatment. Natural heterogeneity was limited to phosphorylation and antenni extensions to the alpha-chain. Mild acid hydrolysis to release OS also hydrolyzed the beta(1-->6) glycosidic linkage of lipid A. OS structures were determined by collisional and resonance excitation combined with MS and multistep MSn which provided sequence information from both neutral loss, and nonreducing terminal fragments. A comparison of OS structures, with earlier knowledge of MAb binding, enzyme treatment, and partial acid hydrolysis indicates a generic overlapping domain for 2C7 binding. Reoccurring structural features include a Hepalpha(1-->3)Hepbeta(1-->5)KDO trisaccharide core branched on the nonreducing terminus (Hep-2) with an alpha(1-->2) linked GlcNAc (gamma-chain), and an alpha-linked lactose (beta-chain) residue. From the central heptose (Hep-1), a beta(1-->4) linked lactose (alpha-chain), moiety is required although extensions to this residue appear unnecessary.   相似文献   
3.
Peng Y  Makarkin VN  Wang X  Ren D 《ZooKeys》2011,(130):217-228
A new genus and species, Undulopsychopsis alexigen. et sp. n., is described from the Early CretaceousYixian Formation of western Liaoning Province, China. This genus is probably most closely related to the Asian Cretaceous genus Kagapsychops Fujiyama, 1978. The family affinity of Undulopsychopsisgen. n. is discussed. The genus is preliminarily assigned to Psychopsidae, although it shares some character states with Osmylopsychopidae (e.g., crossveins are very scarce; Rs1 and 1A are multi-branched).  相似文献   
4.
Makarkin VN  Yang Q  Ren D 《ZooKeys》2011,(130):199-215
Two new species of the genus Sinosmylites Hong are described from the Middle Jurassic locality at Daohugou (Inner Mongolia, China): Sinosmylites fumosussp. n. and Sinosmylites rasnitsynisp. n. This is the oldest known occurrence of the family Berothidae. The berothid affinity of this genus is confirmed by examination of the hind wing venation characteristic of the family. The Late Triassic family Mesoberothidae may represent an early group of Berothidae.  相似文献   
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The propensity to associate or aggregate is one of the characteristic properties of many nonnative proteins. The aggregation of proteins is responsible for a number of human diseases and is a significant problem in biotechnology. Despite this, little is currently known about the effect of self-association on the structural properties and conformational stability of partially folded protein molecules. G-actin is shown to form equilibrium unfolding intermediate in the vicinity of 1.5 M guanidinium chloride (GdmCl). Refolding from the GdmCl unfolded state is terminated at the stage of formation of the same intermediate state. An analogous form, known as inactivated actin, can be obtained by heat treatment, or at moderate urea concentration, or by the release of Ca(2+). In all cases actin forms specific associates comprising partially folded protein molecules. The structural properties and conformational stability of inactivated actin were studied over a wide range of protein concentrations, and it was established that the process of self-association is rather specific. We have also shown that inactivated actin, being denatured, is characterized by a relatively rigid microenvironment of aromatic residues and exhibits a considerable limitation in the internal mobility of tryptophans. This means that specific self-association can play an important structure-forming role for the partially folded protein molecules.  相似文献   
7.
We describe the oldest Kalligrammatidae, two distantly related species of different subfamilies from the Lower Jurassic (lower Toarcian) of Germany: Liassopsychops curvatus Bode, 1953, sit. nov. (Liassopsychopinae n. subfam.) and Ophtalmogramma klopschari n. gen. n. sp. (Kallihemerobiinae). They lived in warm and relatively dry conditions. Subfamily Liassopsychopinae includes the Jurassic genera Liassopsychops and Huiyingogramma, sit. nov., which bear forewings characterized by Sc and RA not fused distally; MP, CuA, CuP, and A1 dichotomously branched; and a well-developed central eye-spot. The forewing of Ophtalmogramma n. gen. is most similar to that of Apochrysogramma Yang et al., 2011. The diversity of early Toarcian kalligrammatids indicates a late Triassic–earliest Jurassic origin of the family. A modified classification of the central eye-spots is proposed based on the presence/absence of four main components, i.e., the central pigmented disc (A), swellings (B), ocules (C), and outer rings (D). The function of the swellings is unclear, but they may have served as pheromone containers.  相似文献   
8.

Background

Lacewings (insect order Neuroptera), known in the fossil record since the Early Permian, were most diverse in the Mesozoic. A dramatic variety of forms ranged in that time from large butterfly-like Kalligrammatidae to minute two-winged Dipteromantispidae.

Principal Findings

We describe the intriguing new neuropteran family Parakseneuridae fam. nov. with three new genera and 15 new species from the Middle Jurassic of Daohugou (Inner Mongolia, China) and the Early/Middle Jurassic of Sai-Sagul (Kyrgyzstan): Parakseneura undula gen. et sp. nov., P. albomacula gen. et sp. nov., P. curvivenis gen. et sp. nov., P. nigromacula gen. et sp. nov., P. nigrolinea gen. et sp. nov., P. albadelta gen. et sp. nov., P. cavomaculata gen. et sp. nov., P. inflata gen. et sp. nov., P. metallica gen. et sp. nov., P. emarginata gen. et sp. nov., P. directa gen. et sp. nov., Pseudorapisma jurassicum gen. et sp. nov., P. angustipenne gen. et sp. nov., P. maculatum gen. et sp. nov. (Daohugou); Shuraboneura ovata gen. et sp. nov. (Sai-Sagul). The family comprises large neuropterans with most primitive wing venation in the order indicated by the presence of ScA and AA1+2, and the dichotomous branching of MP, CuA, CuP, AA3+4, AP1+2. The phylogenetic position of Parakseneuridae was investigated using a phylogenetic analysis of morphological scoring for 33 families of extinct and extant Neuropterida combined with DNA sequence data for representatives of all extant families. Parakseneuridae were recovered in a clade with Osmylopsychopidae, Prohemerobiidae, and Ithonidae.

Conclusions/Significance

The presence of the presumed AA1+2 in wings of Parakseneuridae is a unique plesiomorphic condition hitherto unknown in Neuropterida, the clade comprising Neuroptera, Megaloptera, Raphidioptera. The relative uncertainty of phylogenetic position of Parakseneuridae and the majority of other families of Neuroptera reflects deficient paleontological data, especially from critical important periods for the order, earliest Triassic and latest Triassic/earliest Jurassic.  相似文献   
9.
A well-developed recurrent veinlet is found in the forewing of two species of Nymphidae from the Middle Jurassic locality of Daohugou (Inner Mongolia, China), Liminympha makarkini Ren & Engel and Daonymphes bisulca gen. et sp. n. This is the first record of this trait in the clade comprised of the superfamilies Myrmeleontoidea and Chrysopoidea. We interpret the recurrent veinlet in these species as a remnant of the condition present more basally in the psychopsoid + ithonoid + chrysopoid + myrmeleontoid clade (i.e., as a plesiomorphy). Other venational character states of Daonymphes bisulca of interest include the configuration of subcosta anterior (ScA), which is very similar to that of extant Nymphidae. We consider the short ScA terminating on ScP to be an autapomorphy of Neuroptera.  相似文献   
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