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1.
Breure AS  Ablett JD 《ZooKeys》2011,(138):1-52
The type status is described of 39 taxa classified within the family Amphibulimidae (superfamily Orthalicoidea) and kept in the London museum. One taxon, Bulimus elaeodes Pfeiffer, 1853, is removed to the Strophocheilidae. Lectotypes are designated for Bulimus adoptus Reeve, 1849; Bulimus (Eurytus) eros Angas, 1878; Helix onca d'Orbigny, 1835; Amphibulima pardalina Guppy, 1868. The type status of the following taxon is changed to lectotype in accordance with Art. 74.6 ICZN: Strophocheilus (Dryptus) jubeus Fulton, 1908.As general introduction to this and following papers on Orthalicoid types in the Natural History Museum, a brief history of the London collection is given and several examples of handwriting from different authors are presented.  相似文献   

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利用支持向量机和蛋白质非稳定性指标预测凋亡蛋白类型   总被引:3,自引:0,他引:3  
黄静  石峰  周怀北 《生物信息学》2005,3(3):121-123
细胞凋亡蛋白对生物体的发育和体内稳定、对人们理解程序细胞凋亡的机制非常重要。根据在细胞中的位置,它们一般分为四种类型。文中利用支持向量机和蛋白质的非稳定性指标对98个细胞凋亡蛋白进行分类,取得了较好的结果。  相似文献   

4.
There are various antigenic variants of Orientia tsutsugamushi which are distinguished by immunological and molecular genetic methods targeted at the antigenic diversity of 56-kDa type-specific antigen proteins. The present study was performed to analyze 15 strains successfully isolated from rodents in Saitama Prefecture, Japan, by 56-kDa gene sequence homologies, reactivities with type-specific monoclonal antibodies and polymerase chain reaction (PCR) using type-specific primer-pairs. We demonstrated the presence of a new type of O. tsutsugamushi among the isolates. This new type, designated as the Saitama type, was located in the branch of Karp type in the phylogenetic tree based on 56-kDa gene sequences, but distant from the known Karp types, such as Karp, JP-1 and JP-2, showing less than 90% homology. Strains of this type could not be distinguished by immunological methods from Karp type strains, but a new primer-pair for PCR which specifically amplifies the DNA of this new type strain was designed. This primer-pair may serve to find this strain type in future studies.  相似文献   

5.
Abstract: From the hygrohalophyte Borszczowia aralocaspica Bunge (Chenopodiaceae), a new leaf type with 1-layered chlorenchyma is described as "borszczovoid" and compared with other leaf types in subfamily Salsoloideae. The chlorenchyma is suspected to represent a unique C4 type. Evidence is cited from anatomical studies and documented by micrographs and Carbon isotope determinations (ä13C values). The 1-layered photosynthetic tissue combines all essential anatomical characters of a 2-layered chlorenchyma of regular C4 plants and is in intimate contact with concentrically arranged peripheral bundles. The ä13C values are − 13.03 ‰ from young stems and − 13.78 ‰ from leaves. The results are discussed in the anatomical, physiological and taxonomic framework. In addition, from distantly-related Suaeda species of section Conosperma the conospermoid leaf type is re-described. It is characterized by typical palisade and Kranz layers and differs from the C4 suaedoid type by an external water-storaging hypodermis and an arrangement of Kranz cells reminiscent of the atriplicoid type from subfamily Chenopodioideae. From eight other species of Chenopodiaceae ä13C values are given for the first time.  相似文献   

6.
The state of gustatory neural coding   总被引:1,自引:1,他引:0  
Debates on gustatory neural coding have been dominated by asmall number of fundamental issues since the inception of thefield in 1941. Three of these are discussed in this review:(1) are there basic tastes? (2) are there gustatory neuron types?(3) is the code for a taste read simultaneously across all participatingneurons (across-fiber patterning), or is it confined to a selectivechannel composed of cells of one type (labeled-line or channeling)?No conclusions are drawn regarding (1), primarily because auniversal definition of ‘basic tastes’ is lacking.It is concluded that gustatory neuron types are likely to existafter reviewing the issue from multiple perspectives and discoveringrecurring indications of neuron types from several. A firm conclusion,however, also awaits a widely accepted definition of what constitutesa neuron type. Issue (3) cannot yet be resolved for lack ofdefinitive data, specifically whether the discharges of inhibited,unresponsive, or weakly responsive cells add to (signal) ordetract from (noise) the neural code for a tastant.  相似文献   

7.
Breure AS  Ablett JD 《ZooKeys》2012,(182):1-70
The type status is described for specimens of 84 taxa classified within the families Bothriembryontidae and Odontostomidae (superfamily Orthalicoidea) and kept in the Natural History Museum, London. Lectotypes are designated for Bulimus (Liparus) brazieri Angas, 1871; Bulimus broderipii Sowerby I, 1832; Bulimus fuligineus Pfeiffer, 1853; Helix guarani d'Orbigny, 1835; Bulimus (Tomigerus) ramagei E.A. Smith, 1890; Helix rhodinostoma d'Orbigny, 1835; Bulimus (Bulimulus) ridleyi E.A. Smith, 1890. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Placostylus (Euplacostylus) cylindricus Fulton, 1907; Bulimus pyrostomus Pfeiffer, 1860; Bulimus turneri Pfeiffer, 1860. The following taxon is synonymised: Bulimus oblitus Reeve, 1848 = Bahiensis neglectus (Pfeiffer, 1847).  相似文献   

8.
Summary The amygdaloid complex in the cat was studied in a series of Golgi preparations. Both the lateral and the basal nucleus are composed of the same two cell types, one of which (type P) resembles the pyramidal and the other (type S) the stellate neuron of the cortex. The cortical nucleus can be divided into three layers (I, II, and III–IV) which are made up of cells similar to those in the periamygdaloid cortex. In addition, there are sufficient differences in the organization of these layers to justify a subdivision of the cortical nucleus into lateral and medial parts. The dendrites of neurons in the medial part of the central nucleus, the medial nucleus and the anterior amygdaloid area undergo less branching and carry fewer spines than those of the type P cell. The neurons in the nucleus of the lateral olfactory tract are all of the pyramidal or modified pyramidal type. These findings are discussed in relation to those of previous investigators who employed the Nissl and Golgi methods.This investigation was supported by the Medical Research Council of Canada, Grant M.T. 870. The author wishes to thank Miss Elizabeth Korzeniowski for her technical assistance.  相似文献   

9.
1. Dark diversity represents the set of species that can potentially inhabit a given area under particular ecological conditions, but are currently ‘missing’ from a site. This concept allows characterisation of the mechanisms determining why species are sometimes absent from an area that seems ecologically suitable for them. 2. The aim of this study was to determine the dark diversity of hoverflies in south-eastern Europe and to discuss the role of different functional traits that might increase the likelihood of species contributing to dark diversity. Based on expert opinion, the Syrph the Net database and known occurrences of species, the study estimated species pools, and observed and dark diversities within each of 11 defined vegetation types for 564 hoverfly species registered in south-eastern Europe. To detect the most important functional traits contributing to species being in dark diversity across different vegetation types, a random forest algorithm and respective statistics for variable importance were used. 3. The highest dark diversity was found for southwest Balkan sub-Mediterranean mixed oak forest type, whereas the lowest was in Mediterranean mixed forest type. Three larval feeding modes (saproxylic, and phytophagous on bulbs or roots) were found to be most important for determining the probability of a species contributing to hoverfly dark diversity, based on univariate correlations and random forest analysis. 4. This study shows that studying dark diversity might provide important insights into what drives community assembly in south-eastern European hoverflies, especially its missing components, and contributes to more precise conservation prioritisation of both hoverfly species and their habitats.  相似文献   

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陕西关中地区杂种小麦强优势组合优势型研究   总被引:1,自引:0,他引:1  
选用在陕西关中地区表现优良且某一农艺性状表现突出的11个冬小麦品种(系),根据农艺性状分为大粒型、多穗型、穗重型和中间型4类,组成6种NCII杂交组合模式,研究不同组合模式的杂种优势,探讨根据农艺性状划分杂种小麦亲本优势型在杂种小麦强优势组合选配中的应用.结果表明:在所组配的6种组合模式中,以大粒×多穗型组合模式表现突出,其杂种优势、超亲优势和超标优势均明显高于其它组合,分别达到了59.9%、37.1%和22.5%,因此,依据杂种小麦亲本农艺性状进行亲本优势型划分可以作为杂种小麦亲本选配的依据之一.在陕西关中地区以大粒×多穗型为杂种小麦强优势组合组配模式.  相似文献   

12.
Breure AS  Whisson CS 《ZooKeys》2012,(194):41-80
Type material of 41 Australian Bothriembryon taxa present in Australian museums is critically listed, indicating systematic issues that need to be resolved in further studies. Information on additional type material of 22 taxa in non-Australian museums is compiled. The seven fossil taxa known so far are included in this catalogue. Based on the current systematic position, 38 species are treated in this paper. Bothriembryon jacksoni Iredale, 1939, Bothriembryon notatus Iredale, 1939, Bothriembryon praecelsus Iredale, 1939 and Bothriembryon serpentinus Iredale, 1939 are elevated to species level. Bothriembryon gratwicki (Cox, 1899) is listed as status to be determined.  相似文献   

13.
河南种子植物区系地理研究   总被引:14,自引:0,他引:14  
张桂宾 《广西植物》2004,24(3):199-206
河南省地处中原 ,属于我国南北过渡和东西过渡的重要区域 ,植物区系成分复杂多样并于周围地区联系广泛 ,对其植物区系研究对深入认识本省的自然环境特征及其在我国多种自然区划中的位置等有着重要意义。该文在最新资料的基础上 ,运用区系学原理对河南省种子植物区系的种类组成、地理成分 (属、种 2个层次上 )等进行了系统的分析 ,在此基础上概括出河南植物区系的基本特征为 :(1 )植物种类比较丰富 ,多样性较高 ;(2 )起源古老 ;(3 )地理成分复杂 ,温带成分略占优势 ,过渡性突出 ;(4 )中国特有植物比较丰富。  相似文献   

14.
果实是被子植物特有的繁殖器官,果实的类型影响种子传播的模式、有效性和距离。果实类型的多样性在一定程度上造成了不同植物类群在生态上的差异,并对被子植物的进化速度和分化模式产生重要影响。本文对果实类型多样性形成中起关键作用的通路及其进化机制进行了综述,讨论了影响果实类型进化的各种因素,介绍了有关果实类型进化方向和模式的研究进展,为研究被子植物果实多样性的形成和演化提供新的思路。  相似文献   

15.
A procedure for the quantitation of types I and III collagens by cyanogen bromide peptide analysis was developed with the aim of eliminating certain problems associated with this method. Ion-exchange chromatography reduced high background levels on gel scans used to quantitate the peptides; reduction with beta-mercaptoethanol substantially increased the efficiency of the cyanogen bromide cleavage; use of a concave gradient in acrylamide from 8 to 20% improved the resolution of cyanogen bromide peptides separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis; and a normalization procedure eliminated variations due to differences in the amount of material loaded on the gel system. This method of quantitation was applied to human aorta samples and to collagen secreted by human skin fibroblasts. Metachromasy of type I and type III collagen cyanogen bromide peptides stained with Coomassie blue R-250 was established and this was used as an index of the purity of the cyanogen bromide peptide preparations. Type I and III collagens were prepared from human placental tissue, and these purified collagens were used to construct calibration curves to determine the relationship between the quantity of diagnostic cyanogen bromide peptides present and the composition of the sample in terms of types I and III collagens.  相似文献   

16.
1. Although single cones and double cones in the chicken retina had been documented for more than 30 years, the exact morphology of these cells had never been studied by the scanning electronmicroscopy. In this brief report, we present the evidence for the first time the existence of two types of single cones and three types of double cones (termed as types A, B, and C), each with distinct morphology.2. The proportion of type A:type B:type C double cones, as estimated from the midperipheral and central regions of our scanning specimens, was about 30%:50%:20%.3. Based on the literature data that red oil droplets reside in single cones and yellow oil droplets in chief cones of the double cones, the proportion of single to double cones was deciphered and the relative proportion was estimated to be 1:0.91 in the central region, 1:0.92 in the midperiphery, and 1:0.84 in the periphery.  相似文献   

17.
Summary The ultrastructure of the secretory cells of the adenohypophysis of juvenile sockeye salmon was investigated. Pituitary glands were collected from immature fish transferred experimentally to sea water and subsequently returned to fresh water. The rostral pars distalis contained three cell types: ACTH cells, prolactin cells, and non-secretory cells. The prolactin and non-secretory cells were joined together in the form of follicles by desmosomes and they both had cilia and microvilli projecting into the follicle lumen. Various follicular structures such as lumen, multivesicular structures, and peripheral basement membrane are discussed as possible sites of prolactin cell granule release. The columnar ACTH cells were found at the junction of the rostral pars distalis and the neurohypophysis. The cytoplasmic granules in these cells were characteristically separated from their limiting membrane by a clear space. Multivesicular structures were also found in association with this cell type. The caudal pars distalis also contained three cell types: one acidophil (putative somatotrop) and two basophils (putative thyrotrops and gonadotrops), all of which were similar to those described in adult fish. The pars intermedia contained only one cell type. They appeared to be active cells and were characterized by containing membrane-bounded granules similar to those found in the ACTH cells. Changes in ambient salinity had no apparent effect on any cell type described.The work was supported by a grant in aid of research from the National Research Council of Canada. We wish to thank Mr. R. Lindsay, Mr. C. Cooper, and Mr. G. Longworth for their technical assistance. We would also like to thank Mr. S. Killick of the International Pacific Salmon Fisheries Commission for his assistance in the collection of fish and Dr. H. Cook for his helpful discussion of the project. This paper is No. 058 in the University of Guelph Migration Series.  相似文献   

18.
Aortal collagen typing in monkey and man showed the presence of types I, HI and V in human aorta and types I and III in monkey aorta. Type III collagen was found to be a predominate type in both species. The molecular weight of type III collagen was similar in these species while type I collagen was different. Both monkey and human collagen types I and III were found to be immunogenic. Type I collagen was significantly increased while type III was decreased in human atherosclerotic plaque. Collagen typing in fatty streak remained unaltered.  相似文献   

19.
We evaluate the effects of chronic hypoxia on the metabolic phenotype of the muscle fiber types of humans. The subjects were three Quechua natives residing in the Peruvian Andes at an altitude greater than 3300 m, and three lowlanders from below 700 m. Biopsy specimens were obtained from the vastus lateralis muscles of volunteers. Muscle fibers were identified histochemically as type 1 (oxidative), 2a (oxidativeglycolytic) or 2b (glycolytic). The relative contribution of each fiber type to the total cross-sectional area of each biopsy sample was determined. In individual fibers, the activities of malate dehydrogenase (MDH, citric acid cycle), lactate dehydrogenase (LDH, glycolysis) and adenylokinase (high-energy phosphate) were quantified. The cross-sectional area of the muscle occupied by each fiber type is comparable between Quechuas and lowlanders. Type 1 fibers are the only fiber type to demonstrate statistically significant (P 50.05) differences in enzyme activities between Quechuas and lowlanders. MDH activity is, on average, 19.6% less (P 0.0001) and LDH activity 28.1% more (P 0.0001) in the type 1 fibers of the Quechuas. Chronic hypoxia appears to produce a shift from oxidative to glycolytic metabolism in those fibers which are typically the, most aerobic in human muscle.  相似文献   

20.
Six locomotory muscles of wild common coots, Fulica atra, were analyzed histochemically. Capillarity and fiber-type distributions were correlated to the functional implications and physiological needs of each muscle. Leg muscles exhibit three unevenly distributed fiber types, a pattern that reflects the great variety of terrestrial and aquatic locomotory performances that coots are able to develop. Aerobic zones are presumably recruited during steady swimming and diving, while regions with anaerobic characteristics may be used for bursts of activity such as sprint swimming or during take off, when coots run along the water's surface. Fiber types and capillarization in wing muscles have a marked oxidative trend. High wing beat frequencies, short and broad wings, and the long distance migrations that these birds perform indicate that the presence of high numbers of oxidative fibers and the well developed capillary supply are needed for enhanced oxygen uptake. The pectoralis muscle, except in its deep part, has exclusively fast oxidative fibers with a very high staining intensity for succinate dehydrogenase assay as compared to the same fiber type of other muscles. Its predominant role in flapping flight justifies these characteristics that are typical of fibers with high aerobic metabolism. The deep part of the pectoralis muscle presents a low proportion of an unusual slow anaerobic fiber type. These fibers could play a role during feeding dives when the bird presses the air out of the feathers by tightening the wings against the body. A linear relationship between capillary and fiber densities in all coot muscles studied reflects an adjustment between fiber diameter and vascularization in order to obtain the oxygen for mitochondrial supply. This strategy seems a suitable way to cope with the rigid aerobic constraints that flying and diving impose upon the coot's physiology. J. Morphol. 237:147–164, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

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