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1.
The marine priapulid Priapulus caudatus has a voluminous body cavity filled with a blood-like fluid containing erythrocytes and leucocytes (amoebocytes). The hematocrit of animals weighing 0.5–14 gm was 2–10%. The erythrocytes contain a hemerythrin blood pigment. The structure of the coelomocytes was studied by light and electron microscopy. The erythrocytes are nucleated and contain marginal bands, vacuoles and occasionally crystals. The cytoplasm has few organelles. The leucocytes are amoeboid motile cells, the cytoplasm of which contains numerous organelles. The most conspicuous of these are oval particles, probably representing developmental stages of lysosomes. Most of these organelles contain tubules stretching from one pole to another. In the hind part of the animal, certain tissues, primarily the posterior warts contain large numbers of coelomocytes. The histological picture is complicated, showing some resemblance to the lymphoepithelial tissues of vertebrates. 相似文献
2.
A J Barwijuk K Swietochowska R Pia?cik K Jaroszewicz Z Skrzydlewski 《Acta physiologica Polonica》1989,40(4):404-408
The total phospholipids and their various classes in erythrocytes and blood plasma were determined quantitatively by means of two-dimensional thin-layer chromatography. The total amount of phospholipids in neonate plasma was approximately half of that found in adult plasma, however, the amount of phospholipids in erythrocytes of the neonate was significantly higher. The differences were observed in some classes of phospholipids in the plasma and erythrocytes of neonates as well as adult human beings. 相似文献
3.
Artur Scheib 《Journal of mathematical biology》1989,27(3):369-372
A random competition model is reformulated as an urn model and its behavior is analysed. 相似文献
4.
Ignacy Z. Siemion Artur Pdyczak Jerzy Trojnar Michakl Zimecki Zbigniew Wieczorek 《Peptides》1992,13(6):1233-1237
In connection with our discovery of a strong immunosuppressive activity of cyclolinopeptide A (CLA), we investigated immunosuppressive properties of antamanide and a number of its analogues, including symmetrical antamanide, and compared them with the activities of cyclosporin A and CLA. The peptides were investigated by using plaque forming cell (PFC), graft-versus-host (GvH), delayed type hypersensitivity (DTH), and autologous rosette formation cell (ARFC) tests. Antamanide and symmetrical antamanide exhibit an immunosuppressive activity lower than CLA. Linear antamanide fragments are also active. At higher concentrations of the latter peptides, toxic effects occur. 相似文献
5.
Regeneration of transgenic plants of Prunus armeniaca containing the coat protein gene of Plum Pox Virus 总被引:1,自引:0,他引:1
Margit Laimer da Câmara Machado Artur da Câmara Machado Veronika Hanzer Hans Weiss Ferdinand Regner Herta Steinkellner Diethard Mattanovich Regina Plail Elisabeth Knapp Birgit Kalthoff Hermann Katinger 《Plant cell reports》1992,11(1):25-29
Summary A system was developed which allows the transfer of foreign genes into apricot cultivars. We report the transformation and regeneration of Prunus armeniaca plants with Agrobacterium tumefaciens strain LBA 4404 containing various binary plasmids, pBinGUSint, carrying the marker gene ß-glucuronidase (GUS) and pBinPPVm, carrying the coat protein gene of Plum Pox Virus (PPV). The marker gene GUS was used for optical evaluation of the efficiency of the transformation system. The coat protein gene of PPV was used to introduce coat protein mediated resistance against one of the most important pathogens of stone fruit trees in Europe and the whole Mediterranean area. This is the first report of the successful integration of a viral coat protein gene into a fruit tree species, opening a new perspective on the control of the disease.Abbreviations GUS
ß-glucuronidase
- PPV
Plum Pox Virus
- BA
6-benzylaminopurine
- NPTII
neomycin phosphotransferase II
- CP
coat protein
- CaMV
Cauliflower Mosaic Virus
- P35S 35S
promoter
- MS
Murashige and Skoog
- PCR
polymerase chain reaction
- P/C/I
phenol/chloroform/isoamylalcohol
- RNase
ribonuclease
- dNTP
deoxyribonucleosidetriphosphate
- DMSO
dimethyl sulfoxide 相似文献
6.
7.
Molecular mechanisms of endotoxin activity 总被引:20,自引:0,他引:20
Jens Schletter Holger Heine Artur J. Ulmer Ernst T. Rietschel 《Archives of microbiology》1995,164(6):383-389
Endotoxin (lipopolysaccharide, LPS), a constitutent of the outer membrane of the cell wall of gramnegative bacteria, exerts
a wide variety of biological effects in humans. This review focuses on the molecular mechanisms underlying these activities
and discusses structure-function relationships of the endotoxin molecule, its interaction with humoral and cellular receptors
involved in cell activation, and transmembrane and intra-cellular signal transduction pathways. 相似文献
8.
The Drosophila neuromusculin (nrm) gene encodes an immunoglobulin-like (Ig-like) cell adhesion molecule expressed in the precursors of the embryonic peripheral nervous system (PNS), in the midline precursors of the central nervous system (CNS), and in muscles. During the initial phases of CNS axonogenesis, nrm is expressed in cells involved in the development of commissures and longitudinal tracts. Mutations which alter expression of nrm mRNAs cause aberrant development of commissures and longitudinal axon pathways. Defects in the PNS and muscles of nrm mutants are also observed. In most nrm embryos, abnormal development can be detected in a subset of abdominal segments; however, in approximately 1 of 10 nrm embryos, the defects extend to all segments. Herein, we present evidence that nrm plays an important role in early morphogenesis, possibly by mediating or facilitating inductive cell contacts and movements. 相似文献
9.
Twelve indole alkaloids belonging to the Ajmaline-, Sarpagine-, Yohimbine-, and Heteroyohimbine-type have been isolated and identified from cell suspension cultures of Rauwolfia serpentina. Ten of the alkaloids were found for the first time in cultured R. serpentina cells. The yield of the main alkaloid vomilenine was 51 times more than that of differentiated plants. Crude enzymes isolated from this cell suspension culture completely metabolize the biogenetic precursor strictosidine under formation of several alkaloidal compounds. 相似文献
10.
Demonstration of the presence of an ultrafiltrable substance in human serum activating somatomedin A
M H Heulin M Artur J Straczek D Malaprade M Pierson J F Stoltz F Belleville P Paysant P Nabet 《Comptes rendus des séances de la Société de biologie et de ses filiales》1981,175(3):364-371
Human serum contains an ultrafiltrable factor which stimulates the somatomedin activity measured by 35SO4 incorporation into pelvic cartilage of chick embryo, this ultrafiltrable factor activates native serum somatomedin or partially purified somatomedin. The molecular weight determined by fractionated ultrafiltration or chromatography on Biogel P2 is about 350-500 daltons. 相似文献