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1.
Résumé Nous avons fait élever des larves d'Anergates atratulus par des ouvrières deMyrmica laevinodis à 22°C. Pour y parvenir, il n'est pas utile de faire hivernerensemble les larves d'Anergates et les ouvrières deMyrmica. La présence de larves autochtones n'empêche pas lesMyrmica d'élever des larves d'Anergates. Dans toutes les expériences lesMyrmica ont été soumises au fridavant de recevoir des larves d'Anergates. Aucune reine deMyrmica n'a été utilisée dans ces expériences.Sur les 64 larves d'Anergates que nous avons utilisées, 38 se sont transformées en imagos. C'est au début de l'adoption et au moment des métamorphoses que périrent la plupart des 26Anergates perdus. Les femelles vécurent en général 2 ou 3 jours et cherchèrent très tôt à quitter le nid natal. Les mâles vécurent 2 à 3 semaines.
Summary Larvae ofAnergates atratulus were experimentally reared by workers ofMyrmica laevinodis, at 22°C. An overwintering of both larvae ofAnergates and workers ofMyrmica is not necessary for the success of that experiment. The presence of larvae ofMyrmica does not keep theMyrmica from rearing larvae ofAnergates. The workers ofMyrmica have been cooled, in all the experiments, before receiving larvae ofAnergates. No queen ofMyrmica have been used in that experiments.38 of the 64 larvae ofAnergates used became imagos. Most of the 26 lostAnergates died at the beginning of the adoption and during the metamorphosis. The females lived generally 2 or 3 days and tried, very early, to leave their native nest. The males lived 2 or 3 weeks.

Anergates atratulus Myrmica laevinodis, 22 . bmecme Anergates Myrmica. Myrmica Anergates. Myrmica Anergates. Myrmica . 64 Anergates , 38 . 26 Anergates 2 3 . 2 3 .
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2.
Mycolic acid patterns of some species of Mycobacterium   总被引:5,自引:0,他引:5  
Representative strains of some species of Mycobacterium were degraded by both acid and alkaline methanolysis. Two-dimensional thin-layer chromatography was used to determine the patterns of mycolic acids and other long-chain components in these methanolysates. Patterns composed of -, methoxy- and ketomycolates were found in Mycobacterium asiaticum, Mycobacterium bovix, Mycobacterium gastri, Mycobacterium gordonae, Mycobacterium kansasii, Mycobacterium marinum and Mycobacterium tuberculosis; a representative of Mycobacterium thermoresistibile also contained lower molecular weight -mycolates in addition to these three acids. In representatives or Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium nonchromogenicum, Mycobacterium novum, Mycobacterium paratuberculosis, Mycobacterium scrofulaceum, Mycobacterium terrae, Mycobacterium xenopi, and Mycobacterium sp. MNC 165 - and ketomycolates were accompanied by -carboxymycolates and 2-eicosanol and homologous alcohols which are derived from wax-ester mycolates. Mycobacterium fortuitum and Mycobacterium giae contained - and epoxymycolates and both serovars of Mycobacterium simiae had a very characteristic pattern of -, - and ketomycolic acids. Comparison with data for other mycobacteria showed the chemotaxonomic significance of these mycolic acid patterns.Abbreviations TLC thin-layer chromatography - TBDMS t-butyldimethylsilyl Supplementary data: Copies of the chromatographic patterns of the mycolic acids from all the strains examined can be provided on request from one of the authors (D.E.M.)  相似文献   

3.
The genes were cloned for the two apoprotein subunits, and ,of phycocyanin from the cyanobacterium Spirulina maxima = Arthrospiramaxima) strain F3. The - and -subunit gene-coding regionscontain 489 bp and 519 bp, respectively. The -subunit gene is upstreamfrom the -subunit gene, with a 111-bp segment separating them.Similarities between the -subunits of S. maxima and nine othercyanobacteria were between 58% and 99%, as were those between the -subunits. The maximum similarity between the - and -subunits from S. maxima was 27%.  相似文献   

4.
Six tetrasaccharide fractions were isolated from shark cartilage chondroitin sulfate D by gel filtration chromatography followed by HPLC on an amine-bound silica column after exhaustive digestion with testicular hyaluronidase. Their structures were determined unambiguously by one- and two-dimensional 500 MHz1H NMR spectroscopy in conjunction with HPLC analysis of chondroitinase AC-II digests of the tetrasaccharides. One fraction was found to contain two tetrasaccharide components. All the seven tetrasaccharides shared the common core structure GlcA1-3GalNAc1-4GlcA1-3GalNAc with various sulfation profiles. Four were disulfated comprising of two monosulfated disaccharide units GlcA1-3GalNAc(4-sulfate) and/or GlcA1-3GalNAc(6-sulfate), whereas the other three were hitherto unreported trisulfated tetrasaccharides containing a disulfated disaccharide unit GlcA(2-sulfate)1-3GalNAc(6-sulfate) and a monosulfated disaccharide unit GlcA1-3GalNAc(4-or 6-sulfate). These sulfated tetrasaccharides were demonstrated to serve as appropriate acceptor substrates for serum -N-acetylgalactosaminyltransferase, indicating their usefulness as authentic oligosaccharide substrates or probes for the glycobiology of sulfated glycosaminoglycans.Abbreviations NFU National formulary unit - COSY correlation spectroscopy - HOHAHA homonuclear Hartmann-Hahn - 1D or 2D one- or two-dimensional - IdoA l-iduronic acid - GlcA d-gluco-4-enepyranosyluronic acid - Di-0S GlcA1-3GalNAc - Di-4S GlcA1-3GalNAc(4-sulfate) - Di-4S GlcA1-3GalNAc(4-sulfate) - Di-6S GlcA1-3GalNAc(6-sulfate) - Di-6S GlcA1-3GalNAc(6-sulfate) - Di-diS d GlcA(2-sulfate)1-3GalNAc(6-sulfate) - Di-diSE GlcA1-3GalNAc(4, 6-disulfate) - U G, U, 2S, 4S, and 6S represent GlcA, GalNAc, GlcA, 2-O-sulfate, 4-O-sulfate, and 6-O-sulfate, respectively  相似文献   

5.
Summary Few clinical responses have occurred in preliminary studies using the cytokines tumor necrosis factor (TNF) or interferon (IFN) in cancer patients. This may be related to the observation that many malignant cell lines are resistant to lysis by these cytokinesin vitro. Resistance to lysis by TNF or IFN in many cells is controlled by a protein-synthesis-dependent mechanism, such that when protein synthesis is inhibited cells become sensitive to lysis by these cytokines. Because there is some evidence that TNF and IFN act through different lytic mechanisms and are opposed by different resistance mechanisms, we treated a panel of eight cell lines, five derived from human cervical carcinomas (ME-180, MS751, SiHa, HT-3, and C-33A) and three derived from ovarian carcinomas (Caov-3, SK-OV-3, and NIH: OVCAR-3) with both TNF and IFN to determine whether such combination treatment might maximizein vitro cell lysis. Our results showed that pretreatment with IFN followed by exposure to TNF in the presence of protein synthesis inhibitors increased lysis of seven of the eight cell lines above that seen with either TNF or IFN and inhibitors of protein synthesis. Only the cell line C-33A was resistant to lysis by TNF and IFN, when exposed to these agents both alone and in combination with protein synthesis inhibitors. Clinically, combining the cytokines TNF and IFN with protein synthesis inhibitors may maximize thein vivo lytic effects of these cytokines.Supported by American Cancer Society Career Development Award 90-221  相似文献   

6.
To test the hypothesis that the T-cell receptor (Tcr) gene encodes a natural killer (NK) cell receptor molecule, three human NK clones and fresh peripheral blood lymphocytes with NK activity from two patients with a CD16+ lymphocytosis were analyzed for rearrangements and expression of the human Tcr , , and genes. Two of the clones displayed distinct rearrangements of their Tcr and genes and expressed mature Tcr , , and l RNA. However, one of the clones and both patient samples displayed marked NK activity but failed to rearrange or express any of their Tcr genes. These findings demonstrate that human natural killer activity is not dependent on Tcr gene rearrangement and expression. In addition, they confirm previous findings concerning the lack of Tcr and gene expression in some natural killer cells. Thus, they suggest the existence of additional NK-specific recognition molecules.  相似文献   

7.
An experiment is described which shows in operation the program set out in Foster (1972a) for the investigation of the invariance transformations of visual recognition. The concern in the present study is with the Lie group of rotations SO(2), and a certain centrally located foveal Landolt ring. By presenting to the visual system this Landolt ring and a rotated image in rapid succession, one attempted to induce a specified rotation-type phi-motion. Two subjects were employed. Both reported the existence of the required type of phi-motion for rotations 0 of the Landolt ring about the visual axis with -2/72/7. By appealing to the basic Proposition 2 of Foster (1972 a), the conclusion is reached that the visual system appears capable of effecting upon a certain centrally located foveal annulus the local 1-parameter group of rotations about the visual axis 0, [–2/7,2/7].  相似文献   

8.
    
The expression of CMP-NeuAc: Gal1,4GlcNAc 2,6 sialyltransferase (2,6-ST) [EC 2.4.99.1] and glycoproteins bearing 2,6-linked sialic acids were examined in primary human brain tumours and cell lines. 79% (19/24) of the meningiomas expressed 2,6-ST mRNA, 42% (10/24) of which showed very high expression. 2,6-ST mRNA expression was undetectable in normal brain tissue. In contrast, only 1/13 of the gliomas examined expressed detectable 2,6-ST mRNA. Metastases to the brain did not express measurable amounts of 2,6-ST mRNA. Less expression was found in malignant (i.e., anaplastic) compared to benign (i.e. meningothelial) meningiomas. Two-dimensional SDS-PAGE of glioma and meningioma proteins, followed bySambucus nigra lectin staining, revealed the presence of a glycoprotein bearing 2,6-linked sialic acids,M r=53 kDa and a pI=7.0 (MEN-1) that appeared in all seven of the meningiomas examined, but was expressed at barely detectable levels, if at all, in seven out of the seven glioblastomas examined. Thus, decreased 2,6-ST expression may play a role in the aggressive nature of anaplastic meningiomas, but appears to be virtually absent in all tumours of glial origin.  相似文献   

9.
The effect of cycloheximide and puromycin on 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster has been studied by one-dimensional and two-dimensional SDS polyacrylamide electrophoresis. It is found that puromycin, but not cycloheximide, when applied simultaneously with the hormone enhanced the hormone-induced synthesis of the early and late proteins. However, when puromycin was applied after hormone treatment, only the late proteins were induced. The possible implication of these observations is discussed.  相似文献   

10.
Incubation of Chironomus salivary glands with -amanitine in concentrations from 1 to 10 /ml results in the suppression of puffing and chromosomal 3H-uridine incorporation after 30 to 60 min in 80% of the cells. Nucleolar 3H-uridine incorporation remains completely unaffected. Even 4 h after the injection of high doses of -amanitine into living larvae, nucleolar incorporation is still pronounced. The distribution of resistant cells within the salivary glands suggests that the uptake of -amanitine is subject to physiological restrictions.—A puff typically induced during in vitro incubation of salivary glands was found to be less sensitive to -amanitine than the Balbiani rings.  相似文献   

11.
The effect of interspecific competition and element additions (N and P) on four grassland species (Poa pratensis, Lolium perenne, Festuca valida, Taraxacum officinale) grown under field conditions was studied. Two grasses (L. perenne, F. valida) grown in monoculture (absence of competition) showed lower carbon isotope discrimination (13C) and enriched 15N values. Nitrogen addition (as urea) had inconsistent effects on species 13C while caused enrichment of 15N of P. pratensis and F. valida but strong depletion of 15N of T. officinale. Phosphorous had no significant effect on 13C but depleted 15N of all species.  相似文献   

12.
We have developed a polymerase chain reaction (PCR)-based assay that could effectively reduce the time period required to screen and select for Gall Midgeresistant rice lines under field conditions. The primers for the assay were designed on the basis of sequence information of two phenotype specific random amplified polymorphic DNA fragments which were found to be tightly linked to Gall Midge biotype-1 resistance gene (Gm2). The two RAPD fragments, F81700 in the susceptible parent ARC6650 and F10600 in the resistant parent Phalguna, were identified after screening 5450 loci using 520 random primers on genomic DNAs of ARC6650 and Phalguna. These primers, when used in a multiplexed PCR, amplified specifically a 1.7-kb and 0.6-kb fragment in the susceptible and resistant parents, respectively. When this assay was performed on genomic DNAs of 44 recombinant inbred lines derived from ARC6650 x Phalguna and 5 lines derived from other crosses where one of the parents was Phalguna, ARC6650 or their derivatives, the primers amplified a 1.7-kb fragment in all of the susceptible lines or a 0.6-kb fragment in all of the resistant ones. These markers can be of potential use in the marker-aided selection of Gall Midge biotype-1 resistant phenotypes. As screening for resistance can now be conducted independent of the availability of insects, the breeding of resistant varieties can be hastened.  相似文献   

13.
Infrared analyses of the carrageenan in ten species (representing four genera) of Gigartinaceae and one species of Hypneaceae in different reproductive phases from the northwestern coast of Baja California were studied. Cystocarpic samples of the Gigartinaceae presented varying degrees of a / hybrid. The degree of hybridization was determined based on the ratio between the peak absorbances at 805/845 cm–1. A high correlation was observed between the 805/845 cm–1 and 805/970 cm–1 ratios. Tetrasporic samples of Gigartina leptorhynchos, Iridaea splendens, Rhodoglossum affine and R. roseum, presented a -carrageenan profile, whereas Gigartina tepida, G. exasperata, G. harveyana, G. canaliculata and G. spinosa presented a -carrageenan. The tetrasporic sample of Hypnea valentiae showed a -carrageenan with a very low degree of hybridization.  相似文献   

14.
Climbers are considered heliophytes. They are copious at the margins of forests and natural and man-made clearings. The objective of this paper was to study the initial growth of seedlings maintained under full sunlight and shaded conditions (under a vegetation canopy). The species studied were: Aristolochia galeata, Arrabidea triplinervia, Bidens brasiliensis, Canavalia parviflora, Chamissoa altissima, Cissus sicyoides, Dalechampia pentaphylla, Dicella bracteosa, Dioscorea sp., Gouania virgata, Mascagnia anisopetala, Mutisia coccinea, Oxypetalum molle, Pithecoctenium crucigerum, Rynchosia phaseoloides, Serjania multiflora and Solanum flaccidum. The initial growth of the seedlings was followed under two conditions: at the margin and under the canopy of a mesophyllous tropical forest (22° 4955S–47° 0633W). The climbers showed high rates of growth in sunlight when compared to those under canopy. Most of the species presented higher growth of the shoot than roots but in general no significative differences between root/shoot were found in both treatments. Bidens, Cissus, Mutisia and Pithecoctenium showed a very high mortality rate under canopy but, most of the studied species survived under deep shaded forest for approximately 100 days.  相似文献   

15.
Wind illness is a very common complaint among the Northern Thai, yet is rarely recognized by Thai physicians trained in biomedicine. Persons most susceptible to wind illness are adult women who have ever borne a child. Consequently, data were obtained from 415 everparous women, 43% of whom reported ever having had wind illness and 57%, never having had it. In addition, 20 individuals who had ever had the syndrome were followed for case study, and 13 indigenous healers who traditionally treat clients suffering wind illness were interviewed. Their perceptions of the etiology, symptomatology and treatment of wind illness are reported in Part I. Part II is an attempt to define wind illness in terms of biomedicine and as a consequence of fertility. Part III synthesizes the emic and etic accounts with explanations for the perdurance of wind illness despite the advances of biomedicine and the recent fertility decline in Northern Thailand.  相似文献   

16.
Strain B51 capable of degrading polychlorinated biphenyls (PCB) was isolated from soil contaminated with wastes from the chemical industry. Based on its morphological and chemotaxonomic characteristics, the strain was identified as a Microbacterium sp. Experiments with washed cells showed that strain B51 is able to degrade ortho- and para-substituted mono-, di-, and trichlorinated biphenyls (MCB, DCB, and TCB, respectively). Unlike the known PCB degraders, Microbacterium sp. B51 is able to oxidize the ortho-chlorinated ring of 2,2-DCB and 2,4-DCB and the para-chlorinated ring of 4.4-DCB. The degradation of 2,4-DCB and 4,4-DCB was associated with the accumulation of 4-chlorobenzoic acid (4-CBA) in the medium in amounts comprising 80–90% of the theoretical yield. The strain was able to utilize 2-MCB, 2,2-DCB, and their intermediate 2-CBA and to oxidize the mono(ortho)-chlorinated ring of 2,4,2-TCB and the di(ortho-para)-chlorinated ring of 2,4,4-TCB. A mixed culture of Microbacterium sp. B51 and the 4-CBA-degrading bacterium Arthrobacter sp. H5 was found to grow well on 1 g/l 2,4-DCB as the sole source of carbon and energy.  相似文献   

17.
We have analyzed the hemoglobins of five individual trout from the Ohrid Lake (Salmo L. typicus) by electrophoretic methods, by reversed-phase high-performance liquid chromatography, and by limited structural analyses. The two major classes of hemoglobin are type I (35% of total) and type IV (65%). Type IV is the major oxygen-transporting hemoglobin; it consists of three types of chain (in about equal quantities) and three types of chain (one major and two minor types). Several structural differences have been observed between these three (IV) chains and between the three (IV) chains, suggesting a complex genetic system governing the synthesis of these proteins. Moreover, a few amino acid substitutions occur at positions involved in contacts between chains, which suggests that differences in oxygen affinity may exist between these various type IV hemoglobins. Type I hemoglobin is less complex because it contains one type of chain and two chains; the latter two differ in numerous positions, suggesting duplications of the (I)-globin gene. The and chains of type I hemoglobin differ considerably from the and chains of type IV hemoglobin, indicating the existence of (I)- and (I)-globin genes separate from the (IV)- and (IV)- globin genes.This study was supported in part by the Yugoslav-American Joint Funds, pp 812 (to G.D.E.), and by United States Public Health Service Research Grant HLB-05168 (to T.H.J.H.).  相似文献   

18.
Summary The FhuA protein in the outer membrane of Escherichia coli serves as a multifunctional receptor for the phages T5, T1, 80, for colicin M, for ferrichrome (Fe3+-siderophore) and for the structurally related antibiotic, albomycin. To determine structural domains required for these receptor functions and for export, a fusion protein between FhuA and Iut (receptor for Fe3+-aerobactin and cloacin DF13) was constructed. In the FhuA-Iut hybrid protein, 24 amino acids of FhuA were replaced by 19 amino acids, 18 of which were from Iut. The number of plaque forming units of phage T5 and T1 on cells expressing FhuA-Iut was nearly as high as on cells expressing plasmid-encoded wild-type FhuA. However, 107-fold higher concentrations of phage 80 and 103 times more colicin M were required to obtain a zone of growth inhibition. Truncated FhuA proteins in which the last 24 amino acids at the carboxy-terminus were replaced by 16 (FhuA2) or 3 (FhuAT) amino acids could hardly be detected on polyacrylamide electrophoretograms of outer membrane proteins, due to proteolytic degradation. Sensitivity of cells expressing FhuA2 to phage T5 and T1 was reduced by several orders of magnitude and sensitivity to phage 80 and colicin M was totally abolished. In contrast, cells expressing FhuAT were nearly as sensitive to phage T5, T1, and 80 and to colicin M as cells containing FhuA-Iut. None of the constructs could grow on ferrichrome as sole iron source and none was sensitive to albomycin. Ferrichrome did not inhibit binding of T5 to TonB cells expressing FhuA-Iut (as it did in FhuA+ cells) due to the lack of ferrichrome binding. It is concluded that very small deletions (relative to the size of FhuA with 714 amino acids) at the C-terminal end render FhuA susceptible to proteolytic cleavage. The C-terminal alterations affect sensitivity to FhuA-specific agents very differently. Apparently, the C-terminus is a very important part of FhuA regarding stability and activity. Expression of active FhuA and partially inactive FhuA derivatives in the same cell revealed no negative complementation, suggesting a FhuA monomer as functional unit.  相似文献   

19.
Reactive oxygen species (ROS)-related oxidative damages have been implicated in a wide variety of the pathological processes such as atherosclerosis, inflammation and carcinogenesis. A polysaccharide-enriched fraction (PEF) was isolated from Duchesnea chrysantha, a herbaceous plant, and its antioxidant activity was demonstrated using several assay systems in vitro. The PEF effectively inhibited Cu2+-stimulated low density lipoprotein oxidation in a concentration-dependent way and retarded the conjugated diene formation with the enhancement of the lag phase during oxidation. An assay for DNA strand breaks showed that PEF strongly protected DNA against damage caused by UV or by OH or O2 generated in the metal-catalyzed oxidation system. PEF effectively inhibited Nitroblue Tetrazolium reduction mediated by O2 in a dose-dependent manner. It also competed with 2-deoxy-d-ribose in absorbing OH generated by -irradiation (600 Gy) and thus inhibited the formation malondialdehyde. In conclusion, these evidences indicate that PEF may act as an antioxidant to scavenge O2 , OH or LO2 directly. Our findings suggest the possibility that it may play a role as a potential therapeutic antioxidant in treatment of oxidative damage-derived diseases.  相似文献   

20.
Summary Complex carbohydrates in the human cervix were studied histochemically using lectins, conjugated to horseradish peroxidase and correlated procedures. Stratified squamous epithelium of the exocervix and columnar epithelium of the endocervix in some, but not all specimens showed staining for terminal -N-acetyl-d-galactosamine, -d-galactose, -d-galactose and -l-fucose. the staining for -N-acetylgalactosamine and -galactose, the terminal sugars in blood group A and B antigens respectively, corresponded to a large extent with ABO blood type. One exception was the lack of staining for terminal -N-acetylgalactosamine in endocervical secretions in three of nine blood type A patients. A second exception was the staining for terminal -galactose in endocervical secretions in about half of blood type O and A specimens. The type and amount of glycoprotein formed by endocervical columnar cells differed according to location in superficial compared with deep portions of the glands and according to location at the junction with exocervix compared with the more internal regions. Staining of endothelial cells for blood group A and B antigens was confined to subjects of blood type A and B respectively, although three of nine type A specimens showed no lectin reactivity for group, A antigen. Endothelial cells evidenced affinity forUlex europeus I agglutinin demonstrative of fucose in all specimens. Mast cells disclosed lectin affinity consistent with the presence of terminal or internal mannose orN-acetylglucosamine residues. Two blood type O specimens were examined with conjugated lectins at the ultrastructural level. Secretory granules stained for content of terminal -galactose, -galactose and fucose. These results support and concur with biochemical studies of complex carbohydrates in human cervical tissues. They reveal, in addition, the location of the blood group antigens in the human exocervix and endocervix and the marked heterogeneity among endocervical columnar cells in glycoprotein production.  相似文献   

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