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1.
Günther Pass 《Zoomorphology》1991,110(3):145-164
Summary A comparative investigation of the antennal circulatory organs in representatives of the Onychophora, all subtaxa of the Myriapoda and numerous taxa of the Hexapoda (comprising a total of 54 species) revealed an unexpected diversity in structure and function.In the Onychophora, antennal vessels exist which are connected to the enlarged anterior end of the aorta dorsal to the brain.In the Chilopoda, Diplopoda and Symphyla, antennal vessels exist which originate from the dorsal vessel caudal to the brain. They extend under the optic lobes, lateral to the circumoesophageal connectives, into the antennae.In the Hexapoda, the investigations include representatives of all higher taxa, apart from the Paraneoptera and the Holometabola. Generally, antennal vessels exist. In the Diplura, they originate from the anterior end of the aorta in front of the brain. In all other insects the antennal vessels are separate from the dorsal vessel. Their proximal ends form ampullary enlargements which are attached to the frontal cuticle near the antenna bases. They communicate via valved ostia with the haemolymph sinus in front of the brain. In the Archaeognatha, Zygentoma, Odonata, certain Plecoptera and the Notoptera, no muscles are connected to these organs. In all other groups the ampullae are pulsatile as a result of associated muscles (antennal hearts). These muscles diverge widely in their attachments and act either as compressors (Dermaptera) or dilators of the ampullae (Embioptera, Blattopteroidea, Orthopteroidea, and some Plecoptera).In the Collembola and Ephemeroptera, special antennal circulatory organs are lacking. In some forms the anatomical arrangement of the inner organs, in conjunction with short diaphragms at the antenna bases, apparently leads to a channelling of haemolymph flow. This condition may be explained by the very short antennae of these insects and is considered as a convergent and apomorphic state in these taxa.The antennal vessels are supposed to be homologous within the Tracheata and to represent the lateral arteries of the antenna segment. An origin from the dorsal vessel is considered an ancestral state, which was lost in the stem lineage of the Ectognatha. Specific space constraints within the cephalic capsule are discussed as the possible reason for this loss. The evolution of pulsatile antennal circulatory organs in the Neoptera is the result of the association of muscles with the proximal ampullary ends of the antennal vessels. The attachments and innervation of these muscles indicate a derivation from precerebral pharyngeal dilators.Abbreviations Amp ampulla - Ant antenna - ant anterior - AN antennal nerve - Ao aorta - AV antennal vessel - Br brain - BrSi brain sinus - CC corpora cardiaca - CoeC circumoesophageal connectives - CM compressor muscle of ampulla - CT connective tissue - Dia diagphragm - do dorsal - DM dilator muscle of ampulla - DM1 ampullo-ampullary dilator muscle - DM2 ampullo-pharyngeal dilator muscle - DM3 ampullo-frontal dilator muscle - DM Acc accessory dilator muscle of ampulla - DV dorsal vessel - EB elastic band - FbDM fronto-buccal pharynx dilator muscle - FG frontal ganglion - FSa frontal sac - FSe frontal septum - FSi frontal sinus - Lb labium - LV lateral vessel of aorta - MA mouth-angle - Nr nervus recurrens - Oc ocellus - Oe oesophagus - OeSi oesophageal sinus - Ost ostium - Ph pharynx - Pl labial palpus - RM retractor muscle of mouth-angle - RMl lateral retractor of mouth-angle - RMm medial retractor of mouth-angle - SceSi supracerebral sinus - SD salivary duct - T tentorium  相似文献   

2.
Gelidium cultivation in the sea   总被引:2,自引:2,他引:0  
Gelidium fronds were grown in the sea under a variety of experimental conditions: on rigid, damped and tensioned test farms of various designs, in calmer and more turbulent habitats, at various depths, with and without commercial fertilizer supply. Initially, the effectiveness of a given cultivation strategy was based on the survival and growth of the fronds, here termed bio-assay mariculture. Ambient seawater temperature, nutrient availability, hydrodynamics and other environmental parameters were measured periodically. In-the-sea irrigation of test plants with commercial fertilizers was apparently effective, at least with some farm designs, and when ambient nutrient levels were low. Under optimal conditions, achieved through experimental manipulation of farm design, specific growth rates of over 2% per day were recorded. However, considerable variation in growth rates and in plant performances was observed. It was not always possible to correlate these variations with design modifications or other experimental parameters. In view of these findings, we have reviewed our initial bio-assay approach, namely the assumptions about the design and operation of farm structures and their interactions with the water and the fronds. Methods were developed to quantify these interactions. We advocate a quantitative, hydrodynamic approach in developing an effective cultivation strategy for gelidioid algae and are optimistic about progressing from test-to-commercial scale farms in the near future.  相似文献   

3.
l. Proteoglycans (PGs) in rabbit corneal stroma and mouse sclera have been stained for electron microscopy with Cupromeronic blue in a critical electrolyte concentration (CEC) mode, with and without prior digestion of the tissue by keratanase or chondroitinase ABC to remove the keratan sulphate (KS) or chondroitin-dermatan sulphates (CS or DS) respectively.2. Two classes of PGs, located orthogonally to the corneal collagen fibrils at either the step (band a or c) or gap zone (band d or e) are shown to be KS-PGs or DS-PGs respectively. Four separate and specific PG binding sites on Type I collagen fibrils have thus been identified.3. Rabbit corneal KS and DS PGs each contain two kinds of PG (Gregory JD, Coster L & Damle SP (1982) J. Biol. Chem.257, 6965–6970). We propose that each small protein-rich PG is associated with a specific binding site on the collagen fibril.  相似文献   

4.
Summary The results of previous behavioral studies can be so interpreted that the prey-catching behavior in the toad is elicited if there is a local motion restricted with-in a small part of the visual field, while it is suppressed if there is a global motion over a large part of the visual field. This has led us to design experiments to answer a specific question (yet a very essential one for understanding neural processes underlying this behavior): Are there local motion detectors in the toad's visual system that are not activated by global motion over a large part of the visual field but are activated by local motion confined within a smaller part of it? The present study showed that (1) the majority of the toad's tectal neurons exhibit properties of the local motion detectors as defined above, and (2) these properties can be explained from the receptive field structure revealed in the present experiments. Based on these results, we suggest that the tectal local motion detectors are essential for the detection and localization of small moving prey-objects in the natural environment while ignoring the large moving objects or the self-induced motion of the visual field.Abbreviations ERF excitatory receptive field - G1-5 group 1–5 neurons  相似文献   

5.
Summary The anterior latissimus dorsi muscle of the chick is largely composed of slow-tonic fibres but contains a few fast fibres defined by their acid-labile, alkali-stable myofibrillar ATPase activity. These fibres are referred to as fibres. Differing from the slow-tonic ( and ) fibres which are multiply innervated withen grape endings, the (fast) fibres are innervated by typicalen plaque endings. The innervation of thirty-two fibres were studied closely and it was concluded that about a half of the fibres were focally innervated whereas a half were innervated in two distinct loci byen plaque endings. In only one case, a fast fibre with three widely spaceden plaque endings was observed. The mean intersynaptic length was significantly larger on fibres than on and fibres. No variation in the histochemical properties of myofibrillar ATPase was observed either along the entire length of singly and dually innervated fibres, or along and fibres. It is concluded that the three extrafusal fibre types of the anterior latissimus dorsi muscle maintain uniform histochemical characteristics along their length in spite of a possible innervation by several motoneurons.  相似文献   

6.
Ten previously unreported oligosaccharides have been purified from the urines of human subjects using a combination of gel filtration, ion exchange, and thin-layer chromatographies. Their structures were determined by direct probe mass spectrometry, methylation analysis, and proton NMR spectroscopy of the permethylated oligosaccharide alditols.On the basis of composition, the oligosaccharides could be divided into three groups. Five oligosaccharides containing glycerol were characterized as glucosyl1-1glycerol; glucosyl1-1glycerol; galactosyl1-1glycerol; glucosyl-1-1(fucosyl-1-2)glycerol and/or fucosyl-1-1(glucosyl-1-2)glycerol; and glucosyl-1-1(galactosyl-1-2)glycerol or galactosyl-1-1(glucosyl-1-2)glycerol. Four inositol-containing oligosaccharides were characterized as galactosyl1 (fucosyl1)inositol,N-acetylgalactosaminyl1 (fucosyl1)inositol, fucosyl1-2galactosyl1 (N-acetylgalactosaminyl1)inositol and fucosyl1-2galactosyl1-4-N-acetylglucosaminyl1(N-acetylgalactosaminyl1)inositol. Finally, galactosyl1-3(fucosyl1-2)galactosyl1-6galactosyl1-4(fucosyl1-3)glucose, an oligosaccharide with glucose at its reducing end, was tentatively identified. The significance and possible origins of the carbohydrate structures are discussed.  相似文献   

7.
Three new major, race-specific, resistance genes to powdery mildew (Erysiphe graminis f. sp. hordei) were identified in three barley lines, RS42-6*O, RS137-28*E, and HSY-78*A, derived from crosses with wild barley (Hordeum vulgare ssp. spontaneum). The resistance gene origining from wild barley in line RS42-6*O, showed a recessive mode of inheritance, whereas the other wild barley genes were (semi)-dominant. RFLP mapping of these three genes was performed in segregating F2 populations. The recessive gene in line RS42-6*O, was localized on barley chromosome 1S (7HS), while the (semi)-dominant genes in lines RS137-28*E, and HSY-78*A, were localized on chromosomes 1L (7HL) and 7L (5HL), respectively. Closely linked RFLP clones mapped at distances between 2.6cM and 5.3 cM. Hitherto, specific loci for powdery mildew resistance in barley had not been located on these chromosomes. Furthermore, tests for linkage to the unlocalized resistance gene Mlp revealed free segregation. Therefore, these genes represent new loci and new designations are suggested: mlt (RS42-6*O), Mlf (RS137-28*E), and Mlj (HSY-78*A). Comparisons with mapped QTLs for mildew resistance were made and are discussed in the context of homoeology among the genomes of barley (H-vulgare), wheat (Triticum aestivum), and rye (Secale cereale). Duplications of RFLP bands detected in the neighbourhood of Mlf and mlt might indicate an evolutionary interrelationship to the Mla locus for mildew resistance.  相似文献   

8.
Variable (V) and constant (C) region genes of the mouse kappa light chain have been compared in inbred strains and in geographically isolated or genetically separated populations of mice by Southern blot analysis of endonuclease-restricted germline DNA. In most cases, the C gene is found on a single restriction fragment while the V genes of the V19 and V21 groups are each found on several (6–18) fragments. The restriction fragment (RF) patterns of V19 and V21 groups are both polymorphic when compared among inbred mouse strains. Southern blot patterns of V21 and V19 of inbred strains are also found among some geographically isolated populations of mice, suggesting that inbred strains acquired kappa loci from different subspecies. Some populations of geographical isolates show V21, V19, and C contexts similar to inbred mice while more distantly related species within the genus Mus and laboratory rats show no apparent similarity in context to inbred strains. Variable region genes determining the RF patterns of V19 and V21 appear to be linked to each other and to the C and Lyt-3 loci.  相似文献   

9.
Summary Inheritance of ability to form callus in rice anther culture was studied using the diallel technique. Anthers containing uninucleate microspores from two japonica cultivais (Minehikari and Taipei 309), two indica cultivars (Mingolo and Suweon 290), and 12 F1's of the diallel crosses involving these four parents were cultured on Chaleffs R2 medium and evaluated for callus induction. The parents showed significant differences in anther callus formation, from 41.9% (Taipei 309) to 0% (Suweon 290). Callus induction ability was inherited as a recessive character conditioned by a single block of genes. Additive gene effects were predominant. The japonica types seemed to be good combiners for callus induction. The order of dominance among the four parents was Suweon 290, Mingolo, Minehikari and Taipei 309.  相似文献   

10.
The lipopolysaccharides (LPSs) extracted from the outer membrane of Azospirillum brasilense Sp245 and its Omegon-Km mutants KM018 and KM252 with a hot aqueous solution of phenol were found to differ in the content of carbohydrates, glucosamine, and total phosphorus and in the proportion of octadecenoic and hexadecanoic acids in the lipid moieties of the LPSs. The carbohydrate moieties of the LPSs were heterogeneous in charge. The analysis of the O-specific polysaccharides (O-PSs) of the mutants KM018 and KM252 by gas–liquid chromatography, IR spectroscopy, and NMR spectroscopy showed that they are composed of the same linear pentasugar repeating units 2)--D-Rhap-(1 3)--D-Rhap-(1 3)--D-Rhap-(1 2)--D-Rhap-(1 2)--D-Rhap-(1 as the O-PSs of the parent strain Sp245. The reported differences in the biological activity of the LPSs of the parent and mutant strains can be due to their different chemical composition.  相似文献   

11.
Summary Four E. coli Hfr strains, representing stable (Hfr Cavalli), moderately stable (AB312) and unstable (Ra-1, Ra-2) Hfr states, were used in the isolation of a series of F plasmids. Type II Fs were found to be the most prevalent F plasmid formed from all of the Hfrs, while the percentages of tra Fs increased as the stability of the Hfr increased. Two observations suggested that F formation in unstable Hfrs like Ra-2 may proceed through a type II F precursor. First, the major F products of Ra-2 are tra + type II Fs and, second, other F types (I, II) and classes (tra +, tra) from Ra-2 appeared to be deletion derivatives of a larger F progenitor. By monitoring the molecular changes that occur when the Ra-2 derived type II F pWS200 is transferred from one recA host to another, we have found that all F types and classes can be generated from pWS200 in a recA-independent manner. F sequences involved in the genetic conversions of pWS200 include the oriT locus and the directly repeated junctions of F and chromosomal DNA. A model for the formation of Fs in unstable Hfrs is postulated in which a tra + type II F primary excision product is seen to be modified, through recA-independent processes, to other F types and classes. This model differs from the current model of F formation in that independent excision events from the Hfr chromosome are not seen as the source of type I and type II Fs.These studies have also shown that the formation of tra Fs is a recA-independent process that can occur from the F and Hfr states, that -mediated deletions in pWS200 often demonstrate regional specificity in having endpoints near the ilv operon and that genetic alterations in either replication origin of pWS200 (F oriV, chromosomal oriC) stabilize the replication of this mini-Hfr cointegrate.  相似文献   

12.
Calcium transport has been studied using purified endomembrane vesicles from dark-grown roots of Pisum sativum L. Membranes from a mixed microsomal (non-mitochondrial) fraction showed ATP-dependent calcium uptake which was released by the ionophore A 23187, had a pH optimum of 7.2 and required Mg2+ for uptake. Membranes were further purified using a rapid sucrosedensity-gradient technique yielding vesicles suitable for transport studies, and were identified using marker enzymes. Uptake by plasma membrane, tonoplast, endoplasmic reticulum and Golgi apparatus was indicated. Uptake by membranes of low density (predominantly tonoplast) had a pH optimum of 7.2–7.4 and nucleotide specificity ATP> guanosine 5-triphosphate>inosine 5-triphosphate>ADP>, while that by high-density membranes had a pH optimum of 7.5–7.9 and less specificity for ATP. The importance of regulating sucrose concentrations in calcium transport studies was demonstrated.Abbreviations ER endoplasmic reticulum - GTP guanosine 5-triphosphate - IDPase inosine diphosphatase - IIP inosine 5-triphosphate  相似文献   

13.
Protein kinase C inhibitors, such a calphostin C, abolish the transient nature of pheromone-induced rapid inositol 1,4,5-triphosphate (IP3) responses, suggesting that pheromone signalling is terminated by phosphorylation of specific proteins. Challenging antennal preparations fromHeliothis virescens with species-specific pheromones in the presence of [32P]--ATP led to a rapid, stimulus-dependent incorporation of32Pi into antennal proteins. Pheromone-induced phosphorylation was completely abolished by a blockade of protein kinase C. Electrophoretic analysis revealed that upon stimulation with a pheromone blend two polypeptide bands were labelled; stimulation solely with the major compound (Z-11-hexadecenal) resulted in only a single labelled band. The data indicate that pheromones cause phosphorylation of specific antennal proteins which may be receptors for pheromones.Abbreviations ATP adenosine 5-triphosphate - DMSO dimethylsulphoxide - DPM disintigrations per minute - DTT dithiothreitol - EDTA ethylenediaminetetra-acetic acid - EGTA ethyleneglycol-bis(-aminoethyl ether)N,N,N,N-tetra-acetic acid - GTP guanosine 5-triphosphate - IP3 inositol 1,4,5-trisphosphate - MOPS 3-(N-morpholino)propanesulphinic acid - Pi inorganic phosphate - PDBu phorbol-dibutyrate - SDS sodium dodecyl sulphate  相似文献   

14.
Summary Physiological and endocrine mechanisms mediating long-day (LD 168) triggered sexual maturation were studied in the terrestrial slug,Limax maximus. Our findings were: (1) Maturation was induced in immature slugs seeing only short days (LD 816) after implantation of whole brains from maturing donors, but no development was found in sham-operated control slugs or in animals receiving implants of muscle from mature donors (Table 1). (2) Removal of the optic tentacles did not block maturation in LD 168 or promote maturation in LD 816 (Fig. 1). (3) Gonadectomy (castration) abolished penis development in 9 of 11 slugs exposed to LD 168 for periods of up to 31 weeks (Table 2). The results are consistent with a model forLimax reproductive tract development in which the perception of long days by extraocular receptors results in the secretion of a maturation hormone by the brain followed by the production of a separate male-phase sex hormone by the developing gonad.Abbreviations ASO accessory sex organs - DB dorsal bodies - FPSH female-phase sex hormone - MH maturation hormone - MPSH male-phase sex hormone This work was supported in part by grants from NSF (BNS 78-01408) and NIH (MH 27948) to P.G.S. The assistance of Mr. T.M. Gordon, Mr. J.L. Broyles, and Mr. M. Bullock is gratefully acknowledged.  相似文献   

15.
Summary Three different long-arm X isochromosomes and an isodicentric X chromosome were examined by in situ hybridization with X-chromosome-specific -satellite probes and by quantitation of Southern blots hybridized with proximal short-arm probes. Each chromosome had a unique pericentromeric structure. The isodicentric X chromosome was clearly dicentric, showing two distinct -satellite hybridization signals and duplication of short-arm material. Two isochromosomes showed a larger than normal, bifid -satellite signal and also had duplications of different extents of short-arm material. The third X isochromosome could not be distinguished from a classical long-arm isochromosome; it did not have a short-arm duplication and it had a single -satellite signal. These data indicate that rearrangements responsible for X isochromosome formation can occur at numerous locations in the pericentromeric region and that some X isochromosomes may involve duplications of substantial portions of the short arm.  相似文献   

16.
Summary A crossing programme for trispecific hybridization including cultivated barley (Hordeum vulgare L.) as the third parent was carried out. The primary hybrids comprised 11 interspecific combinations, each of which had either H. jubatum or H. lechleri as one of the parents. The second parent represented species closely or distantly related to H. jubatum and H. lechleri. In trispecific crosses with diploid barley, the seed set was 5.7%. Crosses with tetraploid barley were highly unsuccessful (0.2% seed set). Three lines of diploid barley were used in the crosses, i.e. Gull, Golden Promise and Vada. Generally, cv Gull had high crossability in crosses with related species in the primary hybrid. It is suggested that Gull has a genetic factor for crossability not present in cv Vada and cv Golden Promise. One accession of H. brachyantherum used in the primary hybrid had a very high crossability (seed set 54.7%) in combination with cv Vada but no viable offspring was produced. In all, two trispecific hybrids were raised, viz. (H. lechleri x H. brevisubulatum) x Gull (2n=7–30) and (H. jubatum x H. lechleri) x Gull (2n=20–22). The first combination invariably had a full complement of seven barley chromosomes plus an additional chromosome no. 7, but a varying number of chromosomes (19–22) of the wild-species hybrid. The second combination had a full set of barley chromosomes. The meiotic pairing was low in both combinations.  相似文献   

17.
The responses of 7 genotypes of Rhodendron to culture conditions and their establishment as shoot cultures are described. The genotypes represent a broad genetic diversity in the genus. After sterilization and an acclimation period of 3 to 12 months, all the selections were established as shoot cultures on Woody Plant Medium (WPM) supplemented with N6(-2-isopenteny) adenine (2iP). Plants with strong episodic growth cycles required the longer acclimation periods. Utilizing shoots from these cultures, the response to a cytokinin series of 0 to 32 M 2iP or BAP (6-Benzylaminopurine) was analyzed. BAP proved toxic to all but the elipidote and lepidote rhododendrons (R. mucronulatum, R. x Boule de Neige, and R. x PJM); however, even with these selections, 2iP stimulated greater shoot multiplication rates. The optimum 2iP level for shoot multiplication varied little with the genotype and levels of 4 to 16 M generally proved optimal, depending on the specific selection. Adventitious shoot production was observed in 3 selections (R. canadense, R. x Boule de Neige and R. x PJM), but only at 2iP levels above 8 M. Shoot multiplication rates of 7 to 21 times were observed, depending on the selection. Using an average utilizable shoot production rate of 40 shoots per culture per 6 week subculture period, some 75,000 shoots can be generated per square meter of culture space per year. The harvested shoots (microcuttings) rooted readily out-of-culture and the resultant plants grew like seedlings.  相似文献   

18.
Summary An immunocytochemical technique using the peroxidase-antiperoxidase complex (PAP) was applied to identify and characterize the LH-secreting cells in the ovine pituitary at the ultrastructural level. These cells, round or oval in shape, possessing flattened cisternae of the rough endoplasmic reticulum, contain one class of secretory granules (mean diameter 250 nm) and large dense bodies (600 to 800 nm in diameter). LH molecules and the two subunits LH and LH were localized on the secretory granules and on the small granules near the Golgi complex. The large dense bodies, the cisternae of the endoplasmic reticulum and the saccules of the Golgi complex showed no reaction product.Abbreviations used in this Article O-LH ovine luteinizing hormone - b-LH bovine luteinizing hormone - p-LH porcine luteinizing hormone - p-LH porcine LH subunit - p-LH porcine LH subunit - O-FSH ovine follicle stimulating hormone - b-TSH bovine thyrotropic hormone - A-b LH antiserum to bovine LH - A-pLH antiserum to porcine LH subunit - A-pLH antiserum to porcine LH subunit  相似文献   

19.
Summary The antennal trap setae ofLoricera pilicornis (Carabidae) with one mechanoreceptive neuron and 2 or 3 neurons of so far unknown function were characterized electrophysiologically. The setal shaft is conductive, but screens the epithelial cells against electrolytes (5 mM KCl, 200 mM CaCl2).Transepithelial resistances in the setae ranged from 180 to 490 M (25° C) and 320 to 830 M (12° C). Mechanical stimuli reduce the transepithelial voltage by maximally –13 mV (receptor potential), corresponding to (calculated) receptor currents below 30 pA. Spikes superimposed on receptor potentials can be 20 mV p/p and cause transient transeptithelial current changes that exceed the receptor current.Clamp currents greater than 110 pA inward (12° C) across the epithelium elicit positive spikes at frequencies that are essentially independent of current intensity. Outward clamp currents above 25 pA elicit negative spikes of current-dependent frequency with one to three positive smaller pulses superimposed on them. This indicates the coexistance of apical and basal spike generator sites in the sensillar neurons.We conclude: in the cell with the tubular body, mechanical stimuli elicit a receptor current and apical spikes. These spikes can render the receptor lymph cavity sufficiently negative to trigger synchronized apical spikes in the other neurons, too. The apical spikes trigger the less synchronized basal spikes in the individual neurons.Abbreviations TEV transepithelial voltage - TER transepithelial resistance  相似文献   

20.
Summary Human gastrectomy specimens, including 48 carcinomas and 25 selected benign cases showing extensive intestinal metaplasia (IM), were examined in detail histologically and histochemically. IM was classified into complete (type I), incomplete without sulphomucins (type IIA) and incomplete with sulphomucins (type IIB). Type IIB was associated with intestinal but not diffuse cancers (P<0.01) or benign lesions (P<0.01). The mucin profiles of IIB IM were similar to intestinal cancers with sulphomucins predominating overN-acetylsialomucins.O-acetylsialomucins were not seen in IIB IM or tumours but were observed in complete or type IIM. These findings suggest a histogenic link between incomplete IM secreting sulphomucins (or colonic metaplasia) and intestinal cancers of the human stomach.  相似文献   

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