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  • Immunocytochemistry  (35)
  • Nitrogen fixation  (23)
  • Gas chromatography
  • Springer  (76)
  • Blackwell Publishing Ltd
  • Institute of Physics
  • 2020-2024
  • 2005-2009
  • 1980-1984  (76)
  • 1945-1949
  • 1925-1929
  • 1983  (76)
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  • Springer  (76)
  • Blackwell Publishing Ltd
  • Institute of Physics
  • Wiley-Blackwell  (54)
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  • 2020-2024
  • 2005-2009
  • 1980-1984  (76)
  • 1945-1949
  • 1925-1929
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 34 (1983), S. 20-26 
    ISSN: 1570-7458
    Keywords: Dioryctria abietella ; Cone pyralid ; Lepidoptera ; Pyralidae ; Sex pheromone, (Z,E)-9,11-tetradecadienyl acetate ; Single sensillum recordings ; Electroantennography ; Gas chromatography ; Mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'analyse en chromatographie gazeuse associée à une détection électroantennographique a montré que l'acétate (Z,E)-9,11-tétradécadiényle (Z,E)-9,11–14:Ac est l'un des composants de la phéromone de Dioryctria abietella Schiff (Lepid.: Pyralidae). Couplage chromatographie en phase gazeuse spectrometrie de masse a montré la présence d'acétate tétradécadiényle avec un spectre de masse et un indice de rétention identiques au Z,E-9,11–14:Ac Un récepteur cellulaire sensible à la fois au Z,E-9,11–14:Ac et à un extrait de la femelle a été identifié sous l'antenne du mâle. Les analyses des antennogrammes et de la cellule isolée ont étayé la caractérisation du composant de la phéromone comme étant Z,E-9,11–14:Ac. Un récepteur cellulaire additionnel sensible à l'acétate (Z.)-9-tétradécadiényle et à l'acétate (Z.E.)-9,12-tétradécadiényle a été trouvé sur l'antenne du mâle, mais il n'était pas activé par l'extrait de la femelle. Sur le terrain Z,E-9,11–14:Ac, présenté seul, attirait des nombres importants de mâles de D. abietella. L'addition de l'acétate (Z)-9-tétradécényle a inhibé l'attraction des mâles par les pièges.
    Notes: Summary Gas chromatographic analyses coupled with electro-antennographic detection indicated that (Z,E)-9,11-tetradecadienyl acetate (Z,E-9, 11–14:Ac) is a pheromone component of the cone pyralid Dioryctria abietella. Gas chromatographic-mass spectrometric analyses confirmed the presence of a tetradecadienyl acetate with mass spectrum and retention index identical to Z,E-9,11–14:Ac. A receptor cell sensitive to both Z,E-9,11–14:Ac and the female extract was identified on the male antenna. An additional receptor cell sensitive to (Z)-9-tetradecenyl acetate and (Z,E)-9,12-tetradecadienyl acetate was found on the male antenna but was not activated by the female extract. In the field Z,E-9,11–14:Ac presented alone attracted significant numbers of male D. abietella. Addition of (Z)-9-tetradecenyl acetate inhibited the attraction of males to traps.
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  • 2
    ISSN: 1432-041X
    Keywords: Vitellin ; Yolk granule ; Yolk protein ; Silkworm ; Embryogenesis ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Vitellin was purified from eggs of the silkworm,Bombyx mori, by a new method in which vitellin was extracted from isolated yolk granules. The purified vitellin had a molecular weight of 540,000. An antibody against purified vitellin was prepared in rabbits. It reacted with the hemolymph vitellogenin as well as with purified vitellin, but not with other proteins in the hemolymph or in the extract from yolk granules. The anti-vitellin IgG was used to immunocytochemically locate vitellin in theBombyx non-diapause egg during early developmental stages. In the egg, just after oviposition, vitellin was located in internal yolk granules and in small yolk granules of the periplasm. During the early developmental stages studied, vitellin was not metabolized uniformly throughout the egg. The vitellin of the internal yolk granules located at the posterior-dorsal part and of the small peripheral yolk granules was utilized in 16 h and 2 days, respectively, after oviposition. A thin, very vitellin-poor layer was located between the periplasm and the vitellin-rich interior in the newly laid egg. it was always in close contact with the periphery where blastoderm and germ-band cells developed.
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  • 3
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    Environmental management 7 (1983), S. 177-187 
    ISSN: 1432-1009
    Keywords: Nitrogen ; Model ; Agriculture ; Mass balance ; Ground-water ; Denitrification ; Immobilization ; Dry deposition ; Nitrogen fixation ; Nitrate ; Florida
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract A detailed nitrogen budget was devised for agricultural activities in the Florida peninsula, based on routine data published by state agricultural agencies. The model demonstrates that important unmonitored fluxes of nitrogen can often be calculated by mass balance on individual model compartments, and that the reasonability of poorly quantified fluxes can be assessed. The results of such models can be very useful in designing and assessing the results of field experiments and in prioritizing environmental monitoring programs.
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  • 4
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    Archives of microbiology 136 (1983), S. 20-25 
    ISSN: 1432-072X
    Keywords: Hydrogen production ; Nitrogen fixation ; Hydrogen recycling ; Hydrogenase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Mutants of Rhodopseudomonas capsulata lacking uptake hydrogenase activity have been isolated among those unable to grow photoautotrophically. Studies with these mutants showed increases in nitrogenase mediated H2 production from all substrates tested. In addition, photosynthetic synthetic growth on N2 with malate as carbon source was not affeced by the block in H2 uptake even under low light. Under these growth conditions hydrogen was observed to accumulate in mutant but not in wild-type cultures. This finding suggested that H2 was evolved by nitrogenase during N2 fixation by this photosynthetic bacterium and was efficiently recycled in the wild type.
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  • 5
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    Archives of microbiology 135 (1983), S. 287-292 
    ISSN: 1432-072X
    Keywords: Cyanobacteria ; Respiration ; Nitrogen fixation ; Heterocysts ; K m for O2 ; Anabaena variabilis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Simultaneous measurements of acetylene reduction by Anabaena variabilis and the concentration of dissolved oxygen in the suspension were made using a specially designed vessel which allowed measurements under steady-state conditions. The rate of acetylene reduction in the dark increased with increasing oxygen concentrations until a maximum value was reached at 300 μM O2 (corresponding to 30% O2 in the gas phase at 35°C). This presumably results from a requirement for energy provided by respiration. Measurements of the dependence of respiration rate on dissolved oxygen concentration were made under comparable conditions using an open system to allow conditions close to steady-state to be obtained. The respiration rate of diazotrophically grown Anabaena variabilis had a dependence on oxygen concentration corresponding to the sum of two activities. These had K m values of 1.0 μM and 69 μM and values of V max of similar magnitude. Only the high affinity activity was observed in nitrate-grown cyanobacteria lacking heterocysts, and this presumably represent activity in the vegetative cells. The oxygen concentration dependence of the low affinity activity resembled that for the stimulation of acetylene reduction. We interpret this as the result of oxygen uptake by the heterocysts. The results are consistent with the idea that in intact filaments of cyanobacteria O2 enters heterocysts much more slowly than it enters the vegetative cells.
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  • 6
    ISSN: 1432-072X
    Keywords: Ammonia assimilation ; Lichen symbioses ; Nitrogen fixation ; 15N kinetics ; Peltigera canina
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract On following N2-incorporation and subsequent metabolism in the lichen Peltigera canina using 15N as tracer, it was found, over a 30 min period, that greatest initial labelling was into NH 4 + followed by glutamate and the amide-N of glutamine. Labelling of the amino-N of glutamine, aspartate and alanine increased slowly. Pulse-chase experiments using 15N confirmed this pattern. On inhibiting the GS-GOGAT pathway using l-methionine-dl-sulphoximine and azaserine, 15N enrichment of glutamate, alanine and aspartate continued although labelling of glutamine was undetectable. From this and enzymic data, NH 4 + assimilation in the P. canina thallus appears to proceed via GS-GOGAT in the cyanobacterium and via GDH in the fungus; aminotransferases were present in both partners. The cyanobacterium assimilated 44% of the 15N2 fixed; the remainder was liberated almost exclusively as NH 4 + and then assimilated by fungal GDH.
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  • 7
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    Archives of microbiology 135 (1983), S. 103-109 
    ISSN: 1432-072X
    Keywords: RNA polymerase ; Transcription ; Nitrogen fixation ; Symbiosis ; Rhizobium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract DNA-dependend RNA polymerase (EC 2.7.7.6) from Rhizobium japonicum was purified. The subunit structure was found to be ββ′α2σ, with the following apparent molecular weights determined by electrophoresis: M r (β and β') 150,000 each, M r (σ) 96,000, M r (α) 40,000, M r (holoenzyme) 490,000, M r (core enzyme) 380,000. The recovery of σ was 28%. RNA polymerase from aerobically grown R. japonicum cells and from nitrogen-fixing cells have the same electrophoretic properties suggesting that no chemical modification of the enzyme occurs when cells undergo this metabolic differentiation. The enzyme is Mg2+-dependent, rifampicin-sensitive, and has optimal activity at alkaline pH (8–10) and at 35–40° C. It binds strongly to bacteriophage T7 promoters, weakly to antibiotic resistance genes, and not at all to cloned R. japonicum nif DNA. Preliminary in vitro transcription experiments, including nif DNA as template, revealed that additional factors may be required for selective transcription from promoters.
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  • 8
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    Archives of microbiology 136 (1983), S. 219-221 
    ISSN: 1432-072X
    Keywords: Xanthobacter ; Nitrogen fixation ; Oxygen sensitivity ; Nitrogen metabolism ; Glutamine synthetase ; Glutamate synthase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract N2-fixation was investigated in the chemoautotrophic hydrogen bacterium Xanthobacter H4-14. N2-fixing batch cultures of this organism could only be grown at pO2 values of around 0.02 bar, and in continuous culture dissolved oxygen tensions above 16 μM were found to inhibit N2-fixation. Xanthobacter H4-14 utilized a variety of amino acids, nitrate and ammonia as nitrogen sources. Cell-free extracts from steady-state continuous cultures of ammonia grown, nitrate grown and N2-fixing Xanthobacter were assayed for the presence of ammonia assimilation enzymes. No alanine dehydrogenase or glutamate dehydrogenase activity was detected. Ammonia was assimilated exclusively via the glutamine synthetase/glutamate synthase pathway, irrespective of the extracellular concentration of ammonia.
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  • 9
    ISSN: 1432-072X
    Keywords: Nitrogen fixation ; Nitrogenase regulation ; Glutamine synthetase ; Methionine suofoximine ; Rhodospirillaceae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Methionine sulfoximine (MSX), an irreversible inhibitor of glutamine synthetase of Rhodopseudomonas palustris restored nitrogenase activity to cells in which nitrogenase had been completely inhibited by ammonia switch-off. After addition of MSX, there was a lag period before nitrogenase activity was fully restored. During this lag, glutamine synthetase activity progressively decreased, and near the time of its complete inhibition, nitrogenase activity resumed. Nitrogenase switch-off by ammonia thus required active glutamine synthetase. Glutamine itself caused nitrogenase inhibition whose reversal by MSX depended on the relative ratio of MSX to glutamine. Unlike ammonia, glutamine inhibited nitrogenase under conditions where glutamine synthetase activity was absent. This indicates that glutamine is the effector molecule in nitrogenase switch-off, for instance by interacting with the enzymatic system for Fe protein inactivation. The effects of glutamine and MSX were also dependent on the culture age. Possible explanation for this and for the competitive effects are a common binding site within the regulatory apparatus for nitrogenase, or, in part, within a common transport system. Some observations with MSX were extended to Rhodopseudomonas capsulata and agreed with those in R. palustris.
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  • 10
    ISSN: 1432-072X
    Keywords: Azotobacter vinelandii ; Continuous culture ; Oxygen control ; Nitrogen fixation ; Respiratory protection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Azotobacter vinelandii strain OP was grown in continuous culture at various dissolved oxygen concentrations of air (100% air saturation of the medium=225 ±14 μM O2). Sucrose was added as carbon source and either dinitrogen or ammonia as nitrogen sources. Irrespective of the nitrogen source steady state cultures showed the following general responses with dissolved oxygen concentrations increasing from about 1% to 30% air saturation: (i) cell protein levels, (ii) the amount of cell protein formed per sucrose consumed as well as (iii) nitrogenase activity decreased by at least a factor of two while (iv) cellular respiration increased. At higher oxygen concentrations the parameters changed only slightly, if at all. Increasing the sucrose concentration in the inflowing medium (s R) from 3 g/l to 15 g/l increased the total level of cellular respiration with nitrogen-fixing cultures but was more pronounced with ammonium-assimilating cultures. With nitrogen-fixing cultures cell protein levels increased five-fold while the ratio of protein formed per sucrose consumed as well as cellular nitrogenase activity remained unaffected. With ammonium-assimilating cultures the cell protein level was only doubled and the level of cell protein formed per sucrose consumed was decreased at the higher s R. Increasing the dilution rate at a constant oxygen concentration of 45% air saturation resulted in an almost parallel increase of both cellular respiratory and nitrogenase activity at low and moderate dilution rates. At high dilution rates nitrogenase activity increased steeply over the respiratory activity. Nitrogen-fixing cultures adapted to various oxygen concentrations were subjected to oxygen stress by increasing the oxygen concentration for 7 min. In all cases, this resulted in a complete inhibition (‘switch-off’) of nitrogenase activity. Upon restoration of the original oxygen concentration nitrogenase activity returned to a decreased level. The discussion arrives at the conclusion that some of the results are incompatible with the concept of respiratory protection of nitrogenase.
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  • 11
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    Archives of microbiology 136 (1983), S. 81-83 
    ISSN: 1432-072X
    Keywords: Ammonia production ; Anabaena ; Cyanobacteria ; Nitrate reductase ; Nitrogen fixation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the filamentous heterocystous cyanobacterium Anabaena sp. strain ATCC 33047 dinitrogen fixation and nitrate reduction are mutually exclusive processes. Nitrate promotes nitrate reductase synthesis and represses nitrogenase formation. Inhibition of ammonium assimilation by l-methionine-d,l-sulfoximine (MSX) alleviates the repressive effect of nitrate on nitrogenase synthesis, thus indicating that the nitrate effect is indirect through metabolites generated from the ammonium derived from nitrate reduction. In MSX-treated cells both nitrate reduction and dinitrogen fixation take place simultaneously, although at different sites of the filament, without any apparent competition for the required reducing power. The MSX-treated Anabaena cells generate ammonium from both nitrate and dinitrogen, simultaneously.
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  • 12
    ISSN: 1432-072X
    Keywords: Cyanobacteria ; Ultrastructure ; Nitrogen fixation ; Water stress ; Taxonomy ; DNA ; Plasmids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two strains of desiccation-tolerant coccoid cyanobacteria, Chroococcus S24, a marine form, and Chroococcus N41, a cryptoendolith isolated from a hot-desert rock, have been characterized. The mol % DNA base compositions of the strains are 47.1 and 48.9% respectively. Plasmid DNA was not detected in either strain. The pigment contents and nutritional characteristics of the strains are identical. Both lack phycoerythrinoid pigments and, in culture, behave as slow-growing halotolerant marine forms with elevated requirements for Na+, Cl−, Mg2+ and Ca2+. Sucrose was the only carbon source of those tested that supported photoheterotrophic growth. Each strain synthesizes nitrogenase under anaerobic conditions but not in air. Morphologically the two strains are indistinguishable. They are considered to be independent isolates of the same cyanobacterial species. Chroococcus N41 was studied in detail with the electron microscope. When brought to equilibrium at matric water potentials of-168 MPa and lower (to-673 MPa=c0.12a w) the protoplast shrinks, but the cells maintain the same size and diameter as those at-2,156 kPa (MN medium; control); the sheath expands and remains attached to the cell wall outer membrane by fibrils. The cell wall, cell membrane, thylakoid membranes, cyanophycin granules and carboxysomes appeared intact in desiccated cells.
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  • 13
    ISSN: 1432-2048
    Keywords: Glutamine synthetase ; Leghaemoglobin ; Nitrogenase ; Nitrogen fixation ; Phaseolus ; Rhizobium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The activities of glutamine synthetase (GS), nitrogenase and leghaemoglobin were measured during nodule development in Phaseolus vulgaris infected with wild-type or two non-fixing (Fix-) mutants of Rhizobium phaseoli. The large increase in GS activity which was observed during nodulation with the wild-type rhizobial strain occurred concomitantly with the detection and increase in activity of nitrogenase and the amount of leghaemoglobin. Moreover, this increase in GS was found to be due entirely to the appearance of a novel form of the enzyme (GSn1) in the nodule. The activity of the form (GSn2) similar to the root enzyme (GSr) remained constant throughout the experiment. In nodules produced by infection with the two mutant strains of Rhizobium phaseoli (JL15 and JL19) only trace amounts of GSn1 and leghaemoglobin were detected.
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  • 14
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    Cell & tissue research 234 (1983), S. 427-437 
    ISSN: 1432-0878
    Keywords: Corticotropes ; Rat fetus ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Corticotropes of rat fetuses aged 16, 18 and 21 days were localized by the indirect antibody-enzyme method on semithin sections of the pituitary. The development of the ultrastructure of these cells was observed on consecutive ultrathin sections. In comparison with previous data our present results show that identification of a fetal cell type cannot be based entirely on morphological criteria. The structural peculiarities of corticotropes obtained from studies in vivo are compared with those observed in cells maintained in vitro.
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  • 15
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    Cell & tissue research 234 (1983), S. 439-450 
    ISSN: 1432-0878
    Keywords: Avidin ; Avidin-biotin interaction ; Biotin affinity histochemistry ; Biotin hydrazide ; Immunocytochemistry ; Magnum gland ; Secretion ; Oviduct
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The location of endogenous avidin was studied cytochemically in the magnum tissue of the oviduct of laying hens. Two methods, based on an interaction of avidin-biotin with biotin hydrazide-peroxidase (B-HRP) as an affinity reagent, and on an immunoperoxidase technique, were tested by morphological analysis. The data obtained by both methods showed that in the magnum B-HRP is a strictly substitutive reagent for endogenous avidin. Avidin was clearly demonstrated in large amounts in the secretory granules of some epithelial cells and tubular gland cells, but was absent from mucous cells, the goblet cells, which had been believed to be the location of avidin production, and from ciliated cells. These granules had previously been demonstrated by both electron-microscopic cytochemical techniques. Especially in acinar cells, they were nonhomogeneous with a speckled core and a dense peripheral part. They ranged in size from 500 to 2200nm in diameter in the gland and 180 to 720 nm in the epithelium. Columnar epithelial cells containing avidin granules had a strong resemblance to those of the protodifferentiated tubular gland cells in the magnum of chicks pretreated with daily estrogen or estrogen plus progesterone, and might have migrated towards the acinus as substitutional secretory cells. Therefore, the acinar cells of the magnum, considered to be composed of several secretory protein-producing systems, are dependent on estrogen and/or progesterone in the oviduct of the laying hen.
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  • 16
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    Cell & tissue research 234 (1983), S. 547-559 
    ISSN: 1432-0878
    Keywords: Myelin proteolipids ; Oligodendrocytes ; Golgi apparatus ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Purified antibodies directed against myelin proteolipids were isolated by affinity chromatography of whole serum obtained from rabbits inoculated with myelin. These antibodies were specific for light, medium and dark oligodendrocytes. Astrocytes, neurons and their processes were not reactive. Immunocytochemical investigations showed that the membranes of the Golgi complex are highly labeled by these antibodies. Diffuse cytoplasmic labeling was only observed on the light and medium oligodendrocytes and was absent from the dark types. Vesicles possessing a punctate staining were detected in the vicinity of the Golgi complex and the oligodendroglial membrane. A discontinuous labeling of the plasmalemma appears to be characteristic of the actively myelinating light and medium oligodendrocytes. In compact myelin sheaths positive immunostaining was only detected at the dense line. The immunocytochemical localization of the myelin proteolipids in the oligodendrocytes is in accordance with previously published biochemical data.
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  • 17
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    Cell & tissue research 233 (1983), S. 69-80 
    ISSN: 1432-0878
    Keywords: Somatostatin ; Hypothalamus ; Immunocytochemistry ; Human ; Rhesus monkey
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunocytochemical methods were used to compare the localization of somatostatin (SRIF) in the human and rhesus monkey hypothalamus. The distribution of SRIF-containing cell bodies and fibers is similar in the two species. Perikarya are located predominantly in the periventricular region and to a lesser extent in the ventromedial nucleus. Fibers occur in dense clusters within the periventricular region, ventromedial nucleus, arcuate nucleus, median eminence, and pericommissural area of both species. Analysis of serial sections suggests that fibers originate from cells in the periventricular region, extend ventrally through the ventromedial and arcuate nuclei to terminate around the portal vessels of the infundibular stalk, and thereby participate in the regulation of anterior pituitary function. Somatostatinergic fibers are also found surrounding non-immunoreactive perikarya in the ventromedial nucleus and periventricular region of both primates. This arrangement may support somatostatin's postulated role as a neurotransmitter or neuromodulator. The strong similarity between the localization of hypothalamic SRIF in the human and rhesus monkey supports the use of the rhesus monkey as a model for the study of somatostatin as a neuroendocrine regulator in the human.
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  • 18
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Vasopressin ; Dorsomedial hypothalamus ; Amygdala ; Locus coeruleus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Recently, the existence of a vasopressin-immunoreactive cell group was described in the bed nucleus of the stria terminalis (van Leeuwen and Caffé 1983). In the present investigation additional nuclei containing vasopressin-immunoreactive cells were found, after colchicine pretreatment, in the dorsomedial hypothalamus, medial amygdaloid nucleus and the locus coeruleus. Vasopressin-immunoreactive cells in the dorsomedial hypothalamus and medial amygdaloid nucleus are small (8–14 μm and 10–14 μm, respectively), while those in the locus coeruleus are medium-sized (20–25 μm). Incubation with anti-bovine neurophysin II and anti-rat neurophysin revealed staining of the same cell group in the above-mentioned areas. None of these cell groups show stained cells after incubation with anti-oxytocin and anti-bovine neurophysin I. When sections of the homozygous Brattleboro rat, which shows a deficiency in vasopressin synthesis, are incubated with anti-vasopressin, anti-bovine neurophysin II, or anti-rat neurophysin, no immunoreactivity can be observed in these brain regions. The above-mentioned cell groups may contribute to the vasopressinergic innervation of brain sites that have been reported to persist after lesioning of the suprachiasmatic, paraventricular and bed nuclei of the stria terminalis.
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  • 19
    ISSN: 1432-0878
    Keywords: α-Endorphin ; Immunocytochemistry ; Median neurosecretory cells ; Peptidergic neurones ; Calliphora vomitoria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A group of the 24–26 paraldehyde fuchsin-positive median neurosecretory cells (MNC) in the pars intercerebralis of the brain of the blowfly, Calliphora vomitoria, has shown immunoreactivity towards three different antibodies to α-endorphin, a peptide that corresponds to the amino acid sequence present between residues 61 and 76 of the precursor molecule, β-lipotropin (β-LPH). The immunoreactive material could be followed in axons within the median bundle, the tract through which neurosecretory material from the MNC is passed down to the corpus cardiacum (CC). The α-endorphin-immunoreactive material was observed leaving the CC in the cardiac-recurrent nerve, dorsal to the proventriculus, in the direction of the abdomen. The cells that contain the α-endorphin-like material are different from those of the MNC that contain insulin-, pancreatic polypeptide-, and gastrin/CCK-like peptides. This finding demonstrates the considerable complexity and peptidergic nature of the MNC and constitutes further evidence that morphinomimetic-like peptides are present in the nervous system of invertebrates.
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  • 20
    ISSN: 1432-0878
    Keywords: Angiotensinogen ; Liver ; Kidney ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The renin substrate, angiotensinogen, was localized by immunocytochemistry in liver and kidney of normal rats by the use of an antiserum directed against pure rat angiotensinogen. This substrate was also examined in rats after bilateral nephrectomy, which is known to increase plasma angiotensinogen, and in rats treated with colchicine, which inhibits serum protein secretion. In normal rat liver, light microscopy showed the presence of immunoreactive material in a very few cells. The number of stained hepatocytes rose in rats treated with colchicine or after bilateral nephrectomy. Immuno-staining increased further when rats were both nephrectomized and colchicine treated. In the kidney, angiotensinogen was specifically located as granular formations in nephrocytes of the proximal tubule but never in the granular cells of the juxtaglomerular apparatus. The localization of these granular formations under the brush border suggests that angiotensinogen is reabsorbed from the glomerular ultrafiltrate rather than synthesized in the kidney.
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  • 21
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    Cell & tissue research 233 (1983), S. 471-474 
    ISSN: 1432-0878
    Keywords: Prolactinergic neurons ; Immunocytochemistry ; Cerebral ganglion ; Styela plicata
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Peptidergic neurons have been detected in the cerebral ganglion of the ascidian Styela plicata by means of cytochemical methods. After incubation with a mammalian antibody to human prolactin the perikarya show a strong immunoreactivity. The possible function of prolactin-like peptides in the nervous system of protochordates is discussed.
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  • 22
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    Cell & tissue research 234 (1983), S. 125-134 
    ISSN: 1432-0878
    Keywords: Vasopressin ; Immunocytochemistry ; Electron microscopy ; Hypothalamus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Vasopressin-containing neurons, identified by immunocytochemistry, are located predominantly in the posterior magnocellular division of the paraventricular nucleus of the rat hypothalamus. By electron microscopy, the immunoreaction product is seen within the cell bodies and neuronal processes. In the perikarya and dendritic processes, the immunoreactive material is associated primarily with neurosecretory granules. Axonal processes, identified by their content of microtubules and accumulation of neurosecretory granules, show the immunoreaction product in association with both of these organelles. Afferent axo-dendritic, axo-somatic and putative axo-axonic synapses with immunostained vasopressinergic neurons can be identified. The presynaptic profiles do not contain immunoreactive material. This study contributes to the ultrastructural characterization of vasopressinergic neurons in the paraventricular nucleus and of their afferent synaptic input.
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  • 23
    ISSN: 1432-0878
    Keywords: Fibronectin ; Lung ; Development ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a previous study changes in the macrodistribution of fibronectin during rat-lung development were examined. Using the peroxidase-antiperoxidase immunocytochemical technique, we have demonstrated the presence of fibronectin in embryonic, neonatal, and adult rat lung at the ultrastructural level. In the embryo, fibronectin is found both in an intra-and extracellular association with isolated pneumoblasts, and in a periodic distribution along the basal lamina. The neonate displays fibronectin in an intracellular association with early type-I cells and on their basal and luminal surfaces, but not in association with type-II cells. Neonatal basal lamina is diffusely labeled by anti-fibronectin antiserum. Fibronectin in adult tissue is found both intracellularly and on the basal and luminal surfaces of type-I cells but not in type-II cells. The basal lamina and interstitial connective tissue are slightly or non-reactive. These observations confirm and extend our initial suggestion that fibronectin is involved in rat-lung development.
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    Chromatographia 17 (1983), S. 269-284 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Liquid chromatography ; Phenols
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    Topics: Chemistry and Pharmacology
    Notes: Summary Gas and high-performance liquid chromatographic methods in the analysis of phenols are reviewed. Among the great number of phenolic compounds analyzed, alkylphenols, chlorophenols, dihydroxy- and trihydroxybenzenes and biphenols are chiefly considered. The advantages and drawbacks of the methods are discussed, quoting the most important work. Relationships between the structural characteristics of phenols, the stationary phase structure, the mobile phase composition and the retention data are treated. Typical examples of the conditions for GC and HPLC analysis are summarized in tables. The literature comprises over 270 references, most of them recent.
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  • 25
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Average molecular polarizability ; Retention index ; Polycyclic aromatic hydrocarbons
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    Topics: Chemistry and Pharmacology
    Notes: Abstract The Kováts retention indices of 10 polycyclic aromatic hydrocarbons were determined on SE-30, OV-101, SE-52, OV-7 and OV-17 stationary phases. A significant correlation has been found between the retention indices and the average molecular polarizabilities of the analyzed substances. Equations were derived for the direct determination of the average molecular polarizabilities from the retention index values. The influence of the temperature on this relationship is also indicated.
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  • 26
    ISSN: 1612-1112
    Keywords: Esterification in aqueous solution ; iso butyl esters of C1–C20 fatty acids ; Gas chromatography ; Fatty acid analysis
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    Topics: Chemistry and Pharmacology
    Notes: Summary C1–C20 carboxylic acids have been esterified in aqueous solutions with i-butanol. Gas chromatographic analyses have been performed from a single chromatogram. It has been established that esterification in the concentration range of [H2O]/[i-BuOH]=0.01–10.3 can be utilized for the quantitative determination of these carboxylic acids. The presence of water does not interfere in the range of [H2O]/[i-BuOH]=0.01–1.03. In the cases of [H2O]/[i-BuOH]〉1.03, anhydrous sodium sulfate has been used for binding the water, in an amount of [Na2SO4]anh./[H2O]≥0.2.
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  • 27
    ISSN: 1573-5036
    Keywords: Clover ; Fertilizer ; Lotus ; Nitrogen fertilizer ; Nitrogen fixation ; Nitrogen source ; Nodulation ; Trifolium repens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Studies under growth cabinet conditions investigated the effect of source and concentration of nitrogen and timing of nitrogen application on the growth and nitrogen fixation byLotus pedunculatus cv. Maku andTrifolium repens cv. S184. KNO3, NaNO3 and NH4NO3 were added at transplanting at the following rates: 3.33, 7.78 and 13.33 mg N/plant. KNO3 was added at 3.33 and 7.78 mg N/plant at 0, 6, 12, 18, 24 or 30 days after transplanting. Lotus shoot weight increased with all increasing nitrogen sources but clover only responded to KNO3 and NaNO3. The root weight of both species increased with increasing KNO3 and NH4NO3. The percentage increase in lotus and clover shoot growth was greater than that of root growth when KNO3 was added within a week of transplanting. Increases in growth by both species resulted from added nitrogen except with lotus when NaNO3 was applied where increased nitrogen fixation also contributed to increased growth. Weight and number of effective nodules on both species were increased with 3.33 mg N per plant as KNO3 but nitrogen fixation was not affected. Addition of 13.33 mg N as NaNO3 reduced weight and number of effective nodules in both species and also nitrogen fixation by lotus. KNO3 increased growth and nodulation of both species when applied within one week after transplanting. Nodulated lotus plants responded to KNO3 by increasing growth but not nodulation. KNO3 appeared to affect infection and development of nodules on lotus and may affect the growth of existing nodules on clover.
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    Plant and soil 72 (1983), S. 321-334 
    ISSN: 1573-5036
    Keywords: Leguminous plants ; Nitrogen fixation ; Protein ; Seed ; Yield
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Mineral nitrogen did not increase grain yield and seed protein levels ofVicia faba L. andLupinus luteus L. in field trials and pot experiments. Fixed N2 was substituted by mineral nitrogen in these cases because of inhibition of N2 fixation by mineral nitrogen. Contrary to these results mineral nitrogen increased grain yields and seed protein amounts ofLupinus albus L.,Pisum sativum L., andGlycine max. (L.) Merr. The nitrogen effect was caused at an early stage by saving energy due to inhibition of N2 fixation (measurement of gas exchange by means of IRGA). In case of the N application after flowering grain, yields and seed protein levels increased because the mineral N was an additional nitrogen source for plants. At this stage the plants had ceased fixing atmospheric nitrogen. The high sink activity of growing fruits induced a lack of assimilates in nodules (determined by means of14CO2 application). The N effect was therefore the consequence of the lower assimilate pool for supplying root nodules in these plants in comparison withVicia faba L. andLupinus luteus L. Hence it follows that response to mineral nitrogen can be a criterion for discovering more effective Rhizobium-host combinations.
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    Plant and soil 73 (1983), S. 431-434 
    ISSN: 1573-5036
    Keywords: Nitrogen fixation ; 15N2 diffusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The kinetic of15N2 diffusion has been measured in a system similar to that for the estimation of N2 fixation in plant microorganism associations cultivated in soil. The15N2 enrichment of the soil atmosphere reached an homogenous value one hour after injection of15N2 and is identical to that obtained by calculation, indicating that no adsorption occurs in the soil particles.
    Notes: Résumé La cinétique de diffusion du15N2 est mesurée sur un système identique à ceux pouvant être utilisés pour la mesure de fixation de l'azote chez les associations plantes-microorganismes cultivées sur sol. L'enrichissement homogène de l'atmosphère du sol est obtenu une heure environ après l'injection de15N2 et correspond à l'enrichissement calculé, ce qui indique qu'aucune adsorption n'a lieu dans les particules du sol.
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    Plant and soil 75 (1983), S. 131-138 
    ISSN: 1573-5036
    Keywords: Hydrogen inhibition ; Nitrogen fixation ; Peas ; Relative efficiency ; Rhizobium leguminosarum ; Root nodules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Experiments were performed to investigate the causes of low relative efficiency, RE, in legume root nodules. Nitrogen fixing activity and RE varied with time of incubation of nodules and with different temperatures and oxygen concentrations. The effects of nitrogen concentration and carbon dioxide concentration were also examined. In each case the RE was inversely related to nitrogen fixing activity; measured by acetylene reduction. Increasing the nitrogen concentration had no effect on either nitrogen fixing activity or RE. Experiments with isolated bacteroids gave higher RE values than the whole nodules from which they were isolated. All the results were consistent with hydrogen inhibition of nitrogenase within the nodule being the cause of low RE.
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    Plant and soil 74 (1983), S. 395-406 
    ISSN: 1573-5036
    Keywords: Fix− mutants ; Fix+ revertants ; Macroptilium lathyroides ; Nitrogen fixation ; Rhizobium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Eight ineffective mutant strains were isolated from N-methyl-N'-nitro-N-nitrosoguanidine mutagenized cultures of cowpea Rhizobium strain 32H1. Strains CR1, CR2, CR3, CR4, CR5 and CR6 induced more, but smaller, nodules than the wild type. With the exception of strain CR2, these mutant strains reduced less than 1% of the amount of acetylene reduced by the wild type, in both the free-living and symbiotic assays. Strain CR2 reduced acetylene in the free-living assay but not in the symbiotic assay. Strains CR7 and CR8 responded variably (5–20% of the wild type) in free-living and symbiotic acetylene reduction assays. Nodules also varied from small white to normal-sized pink nodules. The phenotypic characteristics of the mutant strains were consistant with all leguminous plants tested and were stable upon reisolation from nodules. Fully effective revertants were selected from 4 of the ineffective mutant strains by the use of the leguminous plant,Macroptilium lathyroides. Serology, patterns of resistance to anti-bacterial agents, phage-typing, and antibiotic resistance markers were used to confirm strain identification.
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    Plant and soil 72 (1983), S. 95-105 
    ISSN: 1573-5036
    Keywords: Acetylene reduction ; Inga jinicuil ; Nitrogen fixation ; Nodulation ; Nodule biomass ; Nutrients ; Shading ; Tropics ; Woody legume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary A pot experiment was conducted to assess the effects of different fertilizers and soil shading on nodulation and acetylene reduction ofInga jinicuil seedlings. Initially, seedlings produced maximum nodule biomass when grown with high levels of phosphorus but reduced the most acetylene under intermediate phosphorus fertilization. These response differences, however, gradually diminished with age, being negligible when the seedlings were a year old. Nitrogen fertilization inhibited nodulation and acetylene reduction throughout the experiment. Potassium did not significantly affect nodulation, but low levels of potassium stimulated, and high levels inhibited acetylene reduction activity relative to unfertilized control plants. Neither magnesium nor molybdenum affected nodulation or acetylene reduction. Soil shading resulted in decreased nodule biomass and less nitrogen-fixing activity during summer months. However, the data suggest that shading may favour nitrogen fixation in colder periods by moderating soil temperatures. These results confirm findings from an earlier field study and show that nodulation and nitrogen-fixing activity by leguminous trees is influenced by the types and amounts of nutrients supplied. This suggests that the quantity of nitrogen fixed by leguminous shade trees in coffee plantations may be amenable to manipulation through simple management techniques.
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    Plant and soil 75 (1983), S. 309-342 
    ISSN: 1573-5036
    Keywords: Acetylene reduction ; Amino-acid composition ; Chromosome number ; Cross-inoculation ; Growth various substrates ; Medium composition ; Nitrogen fixation ; Parasponia parviflora ; Root nodule ; Temperate Rhizobium species
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Cross-inoculation experiments withParasponia parviflora plants and a large number of Rhizobium strains isolated from legumes, mainly of temperate origin, showed that strains ofRhizobium trifolii andR. lupini could produce root nodulation in Parasponia. Root nodulation was also obtained with some tropical Rhizobium isolates such as those from Arachis and Albizzia, but not withRhizobium japonicum strains. In addition, strains ofR. leguminosarum, R. phaseoli andR. meliloti produced abnormal root nodules or pseudo-root nodules in Parasponia seedlings. All root nodules induced in Parasponia by foreign Rhizobium species lacked, however, nitrogenase activity. Testing the reverse combination Parasponia-Rhizobium on legumes yielded with regard to root nodulation negative results, except withVigna sinensis and twoMacroptilium species (M. atropurpureum andM. lathyroides). The root nodules produced in the latter legumes showed nitrogenase activity.Trema cannabina seedlings inoculated with Parasponia-Rhizobium invariably did not produce root nodules. The feasibility of Parasponia to accept foreign rhizobia bacteria or to produce pseudo-nodulation is probably genetically determined. In a karyological study it was shown thatParasponia parviflora had the chromosome number 2n=20. Growth experiments revealed thatP. parviflora can be cultivated in water culture, perlite and in soil (pot) culture. It can also be grown in agar tubes, although growth under these conditions is sometimes rather variable. Nitrogenase (C2H2) tests showed that water-culture root nodules were 5–10 times less active than those from perlite culture, soil or agar tubes. On the whole, nitrogenase activity of root nodules grown on the various substrates and receiving different treatments, was rather variable.Vigna sinensis plants inoculated with Parasponia-Rhizobium showed on basis of fresh nodule weight a 3–4 times higher nitrogenase activity as compared with the same strain on Parasponia. However, as shown by acetylene reduction tests of nodule slices, the main activity of mature Parasponia root nodules is situated in the apical part of the root nodule. On fresh weight basis the nitrogenase activity of this nodule section is of the same order as that of leguminous root nodules. Intact Parasponia plants showed higher nitrogenase activities than excised root nodules. The maximal nitrogen fixation rate ofParasponia parviflora plants was 20–25 μmol. C2H4·g−1 fresh weight nodule tissue.h−1, which value is comparable to that of legumes and higher than estimates obtained by Parasponia in the field. No decrease of the nitrogen-fixation rate was observed in Parasponia plants tested in a diurnal cycle during the 12-hours dark period. Amino-acid analyses of Parasponia root nodules showed large quantities of aspartic acid, asparagine, glutamic acid and glutamine suggesting a role of these amino acids in the nitrogen fixation or transport processes. In contrast to actinorhizal root nodules Parasponia root nodules do not contain citrulline. The latter amino acid was, however, found—although in rather low concentration—inVigna sinensis andMacroptilium atropurpureum nodules obtained withParasponia-Rhizobium.
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  • 34
    ISSN: 1573-5036
    Keywords: Genetic control ; Nitrogen fixation ; Pisum sativum L. ; Rhizobium Maternal effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary In pea cv. Afghanistan a recessive gene sym 6 prevents the full expression of nitrogenase activity in root nodules, induced byRhizobium leguminosarum strain F 13. In contrast, nitrogenase activity is fully expressed in pea cv. Iran. A comparison of the reciprocal hybrids of these two plants showed that the size of the plant was determined by the mother plant (maternal effect). Therefore the shoot weight and the total amount of nitrogen fixed are not suitable as parameters for a genetic analysis. The % nitrogen of the shoot and the specific activity of the nodules per gram of nodules are more reliable, but for practical purposes the specific activity of the nodules expressed per gram of shoot tissue can be used.
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  • 35
    ISSN: 1573-5036
    Keywords: Acetylene reduction ; Glycine max L. ; Nitrogen fixation ; Soybean
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary A system for employing open-ended root chambers to measurein situ acetylene reduction rates under field conditions is described. Gas mixtures containing about 2 mbar acetylene were continuously flowed through the chambers providing a continuous record of acetylene reduction. These chambers have been used to measure acetylene reduction rates of soybeans during three growing seasons. The system has proved to be reliable with a high degree of precision. The large amount of plant-to-plant variability observed in N2 fixation research has been confirmed by the data collected with this system. However, such variability in physiological studies can be reduced by using a non-destructive system to compare the response of an individual plant with its rates before treatment.
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    Plant and soil 73 (1983), S. 117-128 
    ISSN: 1573-5036
    Keywords: Light quality ; Nitrogen fixation ; Trifolium repens ; White clover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The possibilities of using light quality treatments to gain an understanding of the mechanisms controlling the allocation of photosynthate for symbiotic nitrogen fixation were studied. White clover (Trifolium repens) plants were grown at the same photon irradiance in red, blue and green light treatments. Growth, nodulation and the carbon/nitrogen economies of the plants were measured. Both photosynthetic rates per unit leaf area and shoot-root ratios were affected by the treatments. However, the carbon/nitrogen economies of the plants and the fraction of the total plant weight allocated to nodule growth were unaffected.
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    Plant and soil 73 (1983), S. 151-153 
    ISSN: 1573-5036
    Keywords: Acetylene reduction ; Beijerinckia ; C3 and C4 plants ; Nitrogen fixation ; Phyllosphere ; Wettability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Nitrogen fixation on leaf surfaces of sugarcane, sorghum, ragi, bamboo and mulberry plants was determined by using acetylene reduction assay. The data revealed varying levels of positive nitrogenase activity on the surfaces. Beijerinckia was observed to be the predominant diazotroph on the leaves. No correlation between fixation rates and C3 or C4 plant species was discerned. The possiblity of improving phyllosphere nitrogen fixation has been discussed in light of the above observations.
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  • 38
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    Plant and soil 73 (1983), S. 299-305 
    ISSN: 1573-5036
    Keywords: Nitrogen fixation ; Rhizobium trifolii populations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The effectiveness ofRhizobium trifolii isolates from five locations in southern Britain representing contrasting soil types has been examined with five white clover varieties. The average effectiveness of Rhizobium isolates varied considerably as did the average productivity of plant varieties. The largest differences were, however, associated with Rhizobium population × plant variety interactions. These were often large enough to reverse relative yield differences between white clover varieties. The implications of these results for improving clover productivity in nitrogen fixation are discussed.
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  • 39
    ISSN: 1432-0878
    Keywords: Pars intermedia ; Oxytocin ; Dopamine ; Serotonin ; Immunocytochemistry ; Rabbit, hare
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pars intermedia of the pituitary in the rabbit and hare is abundantly innervated by axons reacting selectively with antibodies against oxytocin. These axons contain dense secretory vesicles about 140 nm in diameter, i.e., smaller than those in the neurosecretory axons of the neural lobe. No fiber elements staining for other peptides (vasopressin, somatostatin, substance P) were observed in the pars intermedia, except rare leu-enkephalin axons restricted to the rostral zone of the gland. Dopaminergic innervation appears to be completely absent from the intermediate lobe. This was shown by the lack of reaction with an antibody against tyrosine-hydroxylase, which did reveal a well-developed tubero-infundibular system of nerve fibers. Axons reacting with an antibody against serotonin were irregularly distributed in the pars intermedia. In the absence of dopaminergic axons, the extensive oxytocin-like innervation may play a major role in regulating the melanotrophic cell activity in the Leporidae.
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    Cell & tissue research 228 (1983), S. 265-276 
    ISSN: 1432-0878
    Keywords: Met- and leu-enkephalin ; Immunocytochemistry ; Ultrastructure ; Lateral septum ; Guinea-pig brain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary By the use of antisera to met-enkephalin and leu-enkephalin, enkephalin-containing structures were visualized in the lateral septum of the guinea-pig brain. The present results do not reveal immunoreactive perikarya in this area. The immunostaining is exclusively located in numerous nerve fibers and endings mostly encompassing neuronal perikarya, which accounts for the fact that at the light-microscopic level cellular somata appear to be immunostained. The immunoreactive terminals and fibers contain granules approximately 110nm in diameter and synaptic vesicles. The origin and the functional role of these numerous enkephalin terminals remain to be established. This work was supported by a grant from INSERM N∘ 804012
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  • 41
    ISSN: 1432-0878
    Keywords: Somatotrops ; Oncorhynchus ; Immunocytochemistry ; Immunodiffusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pituitary somatotrops were localized in four species from the genus Oncorhynchus using an antiserum to chum salmon (Oncorhynchus keta) growth hormone. The antiserum cross-reacted specifically with the acidophils in the caudal pars distalis of all species tested. Corroborative immunodiffusion studies were also conducted with pituitary homogenates from the same species. Immunological identity of the GH molecule was observed for all species tested.
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    Cell & tissue research 233 (1983), S. 389-402 
    ISSN: 1432-0878
    Keywords: Calcium-binding protein (CaBP) ; Immunocytochemistry ; Rat cerebellum ; Development ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Specific antibodies raised against a human 28 000 dalton cerebellar calcium-binding protein (CaBP) were used in an immunocytochemical study during development of the rat cerebellum. Both light and electron microscopy showed (1) that labelling was entirely restricted to the Purkinje cells, (2) that it appeared very early in Purkinje cell development, (3) that the entire cell was labelled from the tip of the smallest dendrites to the axonal terminals, and (4) that with increasing age, the immunoreaction appeared to be progressively restricted to the cell and organelle membranes.
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    Cell & tissue research 234 (1983), S. 319-333 
    ISSN: 1432-0878
    Keywords: Serotonin ; Goldfish ; Immunocytochemistry ; Central nervous system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of immunoreactive serotonin (5-HT) was investigated in the brain and pituitary gland of the goldfish with the use of indirect immunofluorescence technique. Immunoreactive cerebrospinal fluid-contacting neurons were found in the nucleus recessus lateralis and in the nucleus recessus posterions of the hypothalamus. Additional immunoreactive neurons were observed ventro-lateral to the posterior commissure in the nucleus dorsolateralis thalami. This group of cell bodies extends posteriorly as far as the rostral midbrain tegmentum. At the level of the isthmus, numerous immunoreactive cell bodies were located medially between the fiber bundles of the fasciculus longitudinalis medialis. Finally, a few isolated immunoreactive cells were observed in the medulla oblongata. In the pituitary gland, immunoreactive fibers and cells were found primarily in the pars distalis. The origin of the numerous fibers of the telencephalon is not clear, however, they may arise from the perikarya located in the raphe region. The general organization of the ascending and descending 5-HT-systems of the teleost brain appears to be similar to that described in mammals.
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  • 44
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Uteroglobin ; Rabbit ; Epididymis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Using the immunoperoxidase technique and specific goat antiserum to uteroglobin, selective immunochemical staining products are localized in the epididymal epithelium of the caput and proximal corpus region, at the adluminal border of the cauda epididymidis and, as well known, in epithelial cells of the endometrium of pregnant and progesterone-treated rabbits. Specific staining is also seen on spermatozoa. A uteroglobin-like antigen has been similarly localized in alveolar and bronchial epithelial cells of the lung. Testis, prostate, seminal vesicle and ductus deferens do not seem to contain in their tissues immunoreactive uteroglobin-like antigens. Similarly, the uterus and ductus epididymidis of immature rabbits are devoid of immunoreactivity. The presence of uteroglobin-like antigens in tissues other than the endometrium, particularly the ductus epididymidis, stimulates new discussions on the function of this protein in reproductive physiology and fertility research.
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  • 45
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Ontogeny ; LHRH ; Brain ; Teleost fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We have traced the development from birth to puberty of the ir-LHRH producing centers, the nucleus olfactoretinalis (NOR), nucleus praeopticus periventricularis (NPP) and nucleus lateralis tuberis pars posterior (NLT), in male sibling platyfish genetically determined by differing P alleles to mature at two different ages. In sexually immature fish of both genotypes ir-LHRH is first localized in the NOR in perikarya and neuronal fibers and in the NPP where it is limited to the fibers. At the onset of puberty in early maturing fish (11 weeks), ir-LHRH accumulates in perikarya and fibers of the NPP and NLT. Late maturing siblings first have ir-perikarya in the NPP and a few ir-fibers in the NLT at the same developmental stage but at a later age (25–26 weeks). Ir-perikarya are still not seen in the NLT in late-maturing fish even when maturation is complete. This pattern of a sequential development of the three ir-LHRH containing areas of the brain, which we refer to as a “cascade effect”, is similar in early and late genotypes. It is directly correlated to stage of development and not to chronological age. It is clear that the appearance of LHRH producing brain centers precedes, and is presumably essential for, the completion of the development of pituitary gonadotrops and the subsequent maturation of the gonads. The functional significance of the NOR in puberty and reproduction and as a possible site of action for the P gene is discussed.
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  • 46
    ISSN: 1432-0878
    Keywords: Villin ; Intestinal brush border ; Contractile proteins ; Immunocytochemistry ; Immunostaining of blotted gels
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Villin, a 95,000 dalton polypeptide of intestinal brush border which is known to bundle or sever actin filaments in a Ca++-dependent manner, was localized in rat and chicken intestinal epithelium by means of immunocytochemistry at the light- and electron-microscopic levels. Specific antibodies to villin were raised in rabbits immunized with villin purified from chicken intestinal epithelium. Anti-villin bound selectively to the microvillus filament bundle from its tip down to the rootlets. These findings indicate that the well-known stability of rootlet filaments towards elevated Ca++ ion concentrations cannot be explained by the absence of villin. Therefore additional factors must exist which prevent the rootlets from Ca++-villin mediated disassembly.
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    ISSN: 1432-0878
    Keywords: Thyroid ; Pituitary ; Thyrotrops ; Gonadotrops ; Immunocytochemistry ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Alcian blue and periodic acid-Schiff-positive “granular basophils” with electron-dense granules ±160 nm in diameter, and weakly developed irregular cisternae of the granular endoplasmic reticulum (GER) are present in the rostral pars distalis (RPD) and the proximal pars distalis (PPD) of immature rainbow trout. They all react with antisalmon αβ-gonadotropin. However, only granular basophils in the caudal RPD and the rostro-dorsal PPD, often bordering on and sometimes surrounded by neurohypophysial tissue, react with anti-human β-TSH. These cells, considered as the source of thyrotropin, show degranulation and dilatation of the GER-cisternae in fish treated with potassium perchlorate. The thyroids of the goitrogen-treated animals had relatively numerous small follicles with a high epithelium. The remaining granular basophils are gonadotrops.
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    Cell & tissue research 231 (1983), S. 205-213 
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Insulin ; Glucagon ; Pancreatic polypeptide ; Diabetes mellitus
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    Topics: Biology , Medicine
    Notes: Summary Rats rendered diabetic by streptozotocin were subjected to pancreas transplantation. After twenty weeks, the duct-ligated pancreas transplant was studied morphometrically to determine the effect of duct occlusion on the various cell populations of the islets. Concomitantly, the streptozotocin-treated host pancreas was examined for a possible influence of the graft on the diabetic pattern of islet cell population. Twenty weeks after pancreas transplantation, the volume fractions of insulin, glucagon, somatostatin and pancreatic polypeptide cells in the graft islets did not differ from those of the normal control pancreas. In the pancreas of nontransplanted diabetic rats, insulin-positive B cells were reduced from 60–65% to less than 10% of the islet volume, whereas non-B cells were significantly increased in volume density. The changes in fractional volume of the various islet cells correlated fairly well with changes in plasma concentration of the corresponding pancreas hormones. In the recipient's own pancreas, the relative volumes of glucagon and somatostatin cells were unaffected by the pancreas transplant. However, the insulin cell mass was significantly increased, and comprised about 20% of the islet volume, while cells containing pancreatic polypeptide were found only sporadically.
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  • 49
    ISSN: 1432-0878
    Keywords: Pituitary gland ; S-100 protein ; Castration ; Thyroidectomy ; Postnatal development ; Immunocytochemistry ; Rat
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    Topics: Biology , Medicine
    Notes: Summary Pituitary folliculo-stellate cells and associated cells were studied immunohistochemically throughout the life of male and female rats. The marginal layer cells of the pars distalis and intermedia as well as the folliculo-stellate cells were immunostained with anti-S 100 protein serum. The immunostained folliculo-stellate cells in one section were identified as themselves by their ultrastructural properties on the adjacent section. Corticotrophs, thyrotrophs and prolactin cells, characterized by the stellate shape, were not immunostained with anti-S 100 protein serum. Reactivity for S-100 protein appeared on postnatal Day 6 in the marginal layer cells of the pars intermedia, and appeared on Day 10 in those cells of the pars distalis. No immunostained folliculostellate cells appeared before Day 6, but a few of them appeared on Day 10. Thereafter they increased in number, having more intense immunostaining with advancing age. In castrated rats, the immunostained folliculo-stellate cells appeared quite numerously, with branched cytoplasmic processes surrounding the gonadotrophs. In the thyroidectomized rats, however, folliculo-stellate cells lacked ramified cytoplasmic processes, and their topographic affinity for thyrotrophs was negligible.
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  • 50
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    Cell & tissue research 229 (1983), S. 541-550 
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Hagfish ; Somatostatin neurons ; Vasotocin neurons ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The brain of the Pacific hagfish, Eptatretus stouti, was studied immunocytochemically using antisera against somatostatin (SRIH), arginine vasopressin (AVP), and adrenocorticotropic hormone (ACTH). SRIH-immunoreactive perikarya were distributed bilaterally in the postoptic nucleus and in the hypothalamic nucleus. Although several short, stained fibers were observed in the vicinity of the perikarya, SRIH-immunoreactivity was not found in the neurohypophysis, nor in other parts of the brain. On the other hand, presumed arginine vasotocin (AVT) perikarya were distributed in an arc-shaped region extending from the posterior part of the preoptic nucleus to the anterior-most end of the hypothalamic nucleus and projected their fibers to the neurohypophysis. Most presumptive AVT perikarya were located close to the paired prehypophysial arteries near the anterior end of the postoptic nucleus. In the neurohypophysis, abundant presumptive AVT-fibers terminated in the posterior dorsal wall, although some fibers terminated in the anterior dorsal wall and only a few fiber endings were found in the ventral wall. No ACTH-positive cells were detected in the hagfish brain or in the pituitary gland.
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  • 51
    ISSN: 1432-0878
    Keywords: Baboon ; Pituitary gland ; Gonadotrophs ; Mammotrophs ; Somatotrophs ; Thyrotrophs ; Immunocytochemistry
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    Topics: Biology , Medicine
    Notes: Summary The identification and regionalization of four pituitary parenchymal cell types, gonadotrophs, mammotrophs, somatotrophs and thyrotrophs, were studied in the baboon (Papio cynocephalus) hypophysis using immunocytochemistry. The gonadotrophs were homogeneously distributed throughout the entire pars distalis. Both mammotrophs and somatotrophs predominate at the superior and inferior poles of the organ. The medial and anteromedial regions are populated by mammotrophs and thyrotrophs, while the lateral and posterior portions of the pars distalis contain large numbers of somatotrophs.
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  • 52
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    Cell & tissue research 233 (1983), S. 99-111 
    ISSN: 1432-0878
    Keywords: Neurosecretion ; Vasopression ; Osmotic stress ; RIA ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A correlative radioimmunoassay (RIA) and immunocytochemical (ICC) study was carried out on vasopressin (VP) distribution and content in brains of normal and 3-day water-deprived rats. By RIA there were statistically significant differences in brain VP per pg/mg between normal and osmotically stressed specimens in hypothalamus (338.4 versus 134.4), thalamus (4.8 versus 0.9), septum (18.0 versus 3.4), striatum (1.6 versus 0.7) and amygdala (17.3 versus 1.3), but not in other brain regions measured. Pituitary VP decreased from 71.1 to 8.7 ng/mg, and plasma VP rose from 3.6 to 19.3 pg/ml during water deprivation. Application of the peroxidase-anti-peroxidase ICC method of Sternberger to vibratome sections showed that VP-immunoreactivity in dehydrated specimens decreased in perikarya of paraventricular nucleus and suprachiasmatic nucleus, while intrahypothalamic immunoreactive magnocellular fibers appeared more conspicuous due to proliferation of large Herring bodies. In extrahypothalamic sites VP-immunoreactivity in water-deprived rats was visibly reduced in periventricular thalamus and septum. Thus it is apparent that both intra- and extrahypothalamic VP are affected by osmotic stress, and these results are discussed within the context of current ideas relating to co-activation of neurosecretory cells that project to different sites.
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  • 53
    ISSN: 1432-0878
    Keywords: Lung development ; Fibronectin ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the rat lung is a process of continuing morphological change. Indications from work in other mammalian systems suggest that fibronectin may be important in the control of this process. The present study has examined embryonic, neonatal, and adult lung tissue of the rat by means of the peroxidase-antiperoxidase (PAP) technique to demonstrate fibronectin at the light-microscopic level. Positive reaction was observed with anti-fibronectin serum in all stages examined. Control sections treated with pre-immune serum or no primary serum gave negative results in each case. Fibronectin in adult tissue was localized to the alveolar surface and alveolar basal lamina. Neonatal tissue showed fibronectin on pulmonary tubule walls and in basal lamina while embryonic tissue revealed localization of the protein in the basal lamina and in association with small groups of cells at the base of septal buds. These findings suggest a role for fibronectin in the control of rat lung development. The results are discussed in terms of the known functions of fibronectin as a preliminary matrix for the subsequent deposition of collagenous connective tissue, as a cellular adhesion protein, and as surface-bound material for cellular migration.
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  • 54
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    Cell & tissue research 233 (1983), S. 233-236 
    ISSN: 1432-0878
    Keywords: Y-organ ; Steroid secretion ; Ecdysone ; Immunocytochemistry
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    Topics: Biology , Medicine
    Notes: Summary Ecdysone was demonstrated by ultrastructural immunocytochemistry to be present in the mitochondria of the Y-organs of the crayfish Orconectes limosus. This is in remarkable contrast to the prothoracic glands of insects and suggests substantial differences in the biosynthesis of the same hormone, ecdysone, in crustaceans and insects.
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  • 55
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    Chromatographia 17 (1983), S. 33-36 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Preparative scale chromatography ; Capacity ; Dual-step separation
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    Topics: Chemistry and Pharmacology
    Notes: Summary The capacity of dual-step preparative chromatographic separation systems is considered. It is shown that dualstep separation makes it possible to enhance the capacity of preparative installations as compared with single- and dual-stage purification of the compounds.
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  • 56
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    Chromatographia 17 (1983), S. 44-46 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Natural gas analysis ; Poropak N
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    Topics: Chemistry and Pharmacology
    Notes: Summary A simple gas chromatographic method is described for the rapid analysis of natural gas using thermal conductivity detectors and programmed-temperature operation of a single Poropak N column. The method permits the determination of nitrogen, carbon dioxide and hydrocarbons containing one to seven carbon atoms.
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  • 57
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    Chromatographia 17 (1983), S. 553-559 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Open-tubular (capillary) columns ; Immobilized liquid phases ; Thick-film columns ; Diffusion coefficients
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    Topics: Chemistry and Pharmacology
    Notes: Abstract The influence of the liquid phase film thickness in open-tubular (capillary) columns on the individual resistance-to-mass-transfer terms and on the overall column efficiency is examined from the theoretical point of view. Methods for the calculation of the diffusion coefficients are discussed.
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  • 58
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Open-tubular (capillary) columns ; Immobilized liquid phases ; Thick-film columns ; GC-FTIR
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    Topics: Chemistry and Pharmacology
    Notes: Abstract The performance of a column prepared with an immobilized (chemically bonded) methylsilicone phase having a film thickness of 5μm is investigated in detail. Due to their high sample capacity, such columns are particularly useful when directly coupling gas chromatography with spectroscopic techniques such as Fourier-transform infrared spectroscopy. Thick-film columns can even be used with thermal conductivity detectors.
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  • 59
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    Chromatographia 17 (1983), S. 600-604 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Retention index ; Alkyl benzenes
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    Topics: Chemistry and Pharmacology
    Notes: Summary The additivity concept in the retention index system of Kovats has been examined for a series ofn-alkylbenzenes and theiro- andp-monosubstituted nitro-, amino-, and chloro-derivatives. Anomalous behaviour is exhibited by the first three members of the series on both polar and non-polar stationary phases. For addition of a methylene group ton-propylbenzene or ap-substituted derivative, it is found that the retention increment, Δl CH2, approaches 100 units. However, the strong inductive effect of the group in the ortho position and the steric effects apparent in ano-substituted alkylbenzene lead to large variations of retention increment upon addition of-CH2-to the alkyl chain. A study ofn-alkylbenzene retention on Apiezon L and Carbowax 20M over a wide range of temperatures has verified the linearity of the retention increment with temperature and has revealed that this gradient increases with increasing carbon side-chain length for the first few members of the series, thereafter becoming constant. Functional retention increments, Δlx, for substitution of nitro-, amino- and chloro-groups into the benzene ring are given.
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  • 60
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    Chromatographia 17 (1983), S. 691-692 
    ISSN: 1612-1112
    Keywords: Dichlorophenol isomers ; Sodium benzenesulfonate ; Gas chromatography
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    Topics: Chemistry and Pharmacology
    Notes: Summary It is difficult to separate all the dichlorophenol isomers as free phenols by gas-liquid chromatography. However they were effectively separated on 4,4′-dimethoxyazoxybenzene (liquid crystal), and all the isomers were separated appreciably well on sodium 1-naphthalenesulfonate, 2-naphthalenesulfonate and dodecylbenzenesulfonate.
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  • 61
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    Chromatographia 17 (1983), S. 65-69 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Oxygenates ; Fused-silica capillary columns
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    Topics: Chemistry and Pharmacology
    Notes: Summary A method of analysing gasolines that contain oxygenates has been developed. The method uses a single fusedsilica capillary column and gives quantitative data for the oxygenates and the hydrocarbons in one analysis.
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  • 62
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Trace analysis ; GC-concentration ; Enrichment factor ; Theoretical evaluation
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    Topics: Chemistry and Pharmacology
    Notes: Summary Based on gas chromatographic retention data obtained on a given adsorbent and at a given trap efficiency at different temperatures new equations are proposed for the evaluation of the enrichment factor. These equations are suitable under various preconcentration conditions such as: equilibrium saturation, complete trapping and permissible losses. Compared to known expressions for the evaluation of the enrichment factor the equations suggested consider the band broadening of the impurity in a trap causing a loss of the substance at the adsorption stage and dilution of the sample during desorption when the desorbed impurities are directed into the gas chromatographic column without intermediate freezing out in an graphic column without intermediate freezing out in an empty tube. The new equations may be used to select the optimum preconcentration conditions providing the necessary sensitivity.
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  • 63
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    Chromatographia 17 (1983), S. 191-194 
    ISSN: 1612-1112
    Keywords: Thermal treatment of MgO and MgCO3 ; Adsorption properties ; Gas chromatography
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    Topics: Chemistry and Pharmacology
    Notes: Summary The changes in the chromatographic properties of MgO and MgCO3 due to thermal treatment was investigated. The experimental results show that thermally treated MgO and MgCO3 can be used as stationary phase for the gas-adsorption chromatography of hydrocarbon mixtures.
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  • 64
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    Chromatographia 17 (1983), S. 418-420 
    ISSN: 1612-1112
    Keywords: Separation of metal chelates ; Gas chromatography
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    Topics: Chemistry and Pharmacology
    Notes: Summary A very good separation of the acetylacetonate of AL-(III), Cr(III) and Co(III) has been obtained by gas chromatography, on a column containing OV-17 silicone oil as the stationary phase.
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  • 65
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    Chromatographia 17 (1983), S. 421-425 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Purge and trap sampling ; Cryogenic focussing ; Water analysis
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    Topics: Chemistry and Pharmacology
    Notes: Summary The most important operating parameters of a commercial purge and trap GC apparatus have been investigated. Band broadening problems arising from the slow desorption of compounds from the Tenax trap have been overcome by cryogenic focussing at the beginning of the column. Good results have been obtained with both packed and capillary columns. The sensitivity of the technique is sufficient to detect benzene in water at concentrations below 1μg kg−1 (1 ppb).
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  • 66
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    Chromatographia 17 (1983), S. 241-243 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Detectors ; Flame ionization detector ; History of chromatography
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    Topics: Chemistry and Pharmacology
    Notes: Summary On the occasion of the 25-year anniversary of its invention, this article summarizes the events which led to the development of the flame ionization detector.
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  • 67
    ISSN: 1612-1112
    Keywords: Esterification in aqueous solution ; n-Butyl esters of fatty acids ; Gas chromatography ; Fatty acid analysis
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    Topics: Chemistry and Pharmacology
    Notes: Summary The esterification of C1−C8 fatty acid in aqueous solutions and in the presence of sulfuric or hydrochloric acid and with n-butanol is described. It has been established that the esterification can be used for the quantitative determination of these fatty acids in the concentration ratio range of [H2O]/[n-BuOH]=0.01–5.3. In the concentration ratio range of 0.01–0.8 the water present does not interfere. In the concentration range of above 0.8 anhydrous sodium sulfate is used for binding the water, in the amount of [Na2SO4.anh.]/[H2O]≥0.2.
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  • 68
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    Chromatographia 17 (1983), S. 472-476 
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Liquid stationary phase ; Liquid phase bleeding
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    Topics: Chemistry and Pharmacology
    Notes: Summary The theory of the evaporation of the liquid stationary phase is elaborated and experimentally verified. On the basis of this theory the role played by the losses in the amount of liquid phase present is quantitatively determined. General techniques are examined which minimize the losses; these techniques are based on saturating the incoming carrier gas with liquid phase vapours and raising the pressure of the carrier gas in the column, e.g. by connecting a capillary to the column outlet in order to offer resistance to the gas flow. The application of these techniques ensures stable performance of the gas chromatographic columns using a volatile liquid phase.
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  • 69
    ISSN: 1432-0878
    Keywords: Nucleus lateralis tuberis ; Hypothalamo-hypophysial relationship ; Immunocytochemistry ; Prolactin cells ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the rainbow trout the pars lateralis is the most prominent part of the nucleus lateralis tuberis (NLT). To demonstrate a morphological relationship between this lateral part of the NLT and the pituitary, immunocytochemistry was applied as a staining method. Experiments were carried out on glutaraldehyde-picric acid-acetic acidfixed brain sections of mature male and female rainbow trout using the peroxidase-anti-peroxidase immune technique with an antiserum against 27-S-methylglucagon as the first antibody. Most of the cells in the NLT/pars lateralis reacted with the antiserum. Axons from these cells enter the pituitary, extending exclusively in the numerous neurohypophysial digitations in the pars intermedia. No immunoreactive neurohypophysial protrusions were found in those parts of the adenohypophysis where the gonadotropic cells are located, indicating that the lateral part of the NLT is not directly involved in the control of gonadotropin secretion. In addition to cells of the NLT/pars lateralis only prolactin cells in the rostral pars distalis of the adenohypophysis reacted with the antiserum used.
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  • 70
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    Cell & tissue research 228 (1983), S. 525-534 
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Vasopressin ; Oxytocin ; Bed nucleus, stria terminalis ; Lateral septum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the dorsal and ventral portions of the bed nucleus of the stria terminalis of the rat numerous cell bodies immunoreactive for vasopressin and neurophysin II were found after colchicin pretreatment. These cells are predominantly multipolar but sometimes also bipolar, and have a width and length of approximately 9 and 16 μm, respectively. In the homozygous Brattleboro rat, which is deficient in vasopressin, no immunoreactive vasopressin was found in these cells. Following incubation with anti-oxytocin and anti-bovine neurophysin I, only magnocellular immunoreactive cell bodies were found in the septal region. The consequences of these results concerning the vasopressin fiber pathways in the brain are discussed.
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  • 71
    ISSN: 1432-0878
    Keywords: TRH ; Immunocytochemistry ; Autoradiography ; Arcuate nucleus ; Median eminence ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunocytochemical and autoradiographic localization of thyrotropin-releasing hormone (TRH)-and 3H-TRH-binding sites was studied in the arcuate nucleus-median eminence region of the rat. TRH-like immunoreactivity was found in dense granular vesicles (90–140 nm in diameter) in TRH-like immunoreactive nerve fibers and terminals. In the median eminence, the immunoreactive terminals were observed to be in direct contact with the perivascular basal lamina of the portal vessel and to form synaptoid contacts with tanycytes. In the arcuate nucleus, the immunoreactive terminals were often found to form axosomatic and axo-axonic, and/or axo-dendritic synapses. The uptake of tritiated TRH into the nerve fibers and terminals of the median eminence was also observed by autoradiography and the distribution and localization of silver grains in them were analyzed quantitatively by circle analysis. Thirty minutes after intraventricular infusion of 3H-TRH, radioactive labeling occurred in type-2 and 3-nerve fibers and terminals containing dense granular vesicles in the median eminence. It is therefore suggested that the neurons labeled after 3H-TRH infusion possess certain functions as physiological recognition sites or receptors for TRH.
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  • 72
    ISSN: 1432-0878
    Keywords: Pituitary ; Adenohypophysis ; Luteinizing hormone (LH) ; Immunocytochemistry ; Lamprey
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A mammalian-like immunoreactive luteinizing hormone (LH) has been localized in the cytoplasm of cells in the meso-adenohypophysis of the sea lamprey, Petromyzon marinus L. Specific staining for LH was absent in other regions of the lamprey pituitary.
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  • 73
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    Cell & tissue research 231 (1983), S. 527-532 
    ISSN: 1432-0878
    Keywords: S-100 ; Müller cells ; Immunocytochemistry
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    Topics: Biology , Medicine
    Notes: Summary The localization of S-100 protein in the retina was studied by immuno-electron microscopy. The immunoreaction for S-100 is specifically confined to Müller cells and astrocytes. Long slender cytoplasmic processes of Müller cells and their participation in the formation of the inner and outer limiting membrane were clearly demonstrated with this immunoreaction. The cytoplasmic processes were also revealed to form continuous sheets surrounding blood vessels. Some somata of Müller cells were found in the outer nuclear layer. The results show that immunostaining for S-100 is useful for selective visualization of Müller cells in the mature retina.
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  • 74
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    Cell & tissue research 232 (1983), S. 129-140 
    ISSN: 1432-0878
    Keywords: Serotonin ; Optic lobes ; Insecta ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cellular localization of 5-HT in the optic lobes of three insect species was assayed with the use of antibodies raised against 5-HT. In Schistocerca, Periplaneta, and Calliphora all neuropil regions of the optic lobe, the lamina, medulla and lobula, contain 5-HT-immunoreactive varicose fibres in different patterns, like columns and layers. Such fibres also connect the lobula to neuropil in the lateral protocerebrum. In Calliphora also 5-HT-positive fibres of the medulla and lobula plate have projections to the lateral protocerebrum, whereas the origin of the lamina fibres is not certain. In all species the processes displaying 5-HT-like immunoreactivity appear to be derived from a relatively small number of cell bodies, each neuron thus having processes over a large volume of the neuropil of the optic lobe in different layers.
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  • 75
    ISSN: 1432-0878
    Keywords: Adipokinetic hormone ; Locusta migratoria ; Neurohormone ; Peptidergic neuron ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An antiserum was raised against tyrosine-adipokinetic hormone ([Tyr1]-AKH). In immunohistochemical procedures, it revealed the AKH cells in the glandular lobes of the corpora cardiaca (CC) of Locusta migratoria with high specificity. In addition, an immunologically related peptide was detected in certain neurons of the central nervous system which suggests that this AKH-like peptide may have a neurotransmitter function. The glandular lobes contain immunoreactive AKH cells in all postembryonic stages, and no essential differences in morphology and distribution of the cells in nymphs and adults were seen. The amount of AKH, stored predominantly in the cell projections, differs widely among cells and individuals. The brain of adults and nymphs contains several small populations of intensely stained neurons. In last-instar and adult specimens, each half contains 10–12 “normal”-sized neurons in the protocerebrum (including the optic lobe) and deutocerebrum, and in addition 15–18 small reactive neurons. Their axons and numerous branchings traverse the neuropile of proto-, deuto-, and tritocerebrum, except for the pedunculate bodies and antennal lobes. Some of the axons run into the storage lobe of the CC; it is unknown if their content is released into the haemolymph. Other axons run into the ganglia of the stomatogastric nervous system and into the circumoesophageal connectives. The suboesophageal ganglion also contains 8 immunoreactive neurons. It is unknown to which extent the immunoreactive substances in glandular and nervous tissue are chemically and physiologically related.
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  • 76
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Human TSH β subunit ; Teleosts ; TSH cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A rabbit antiserum raised against human thyrotropin (TSH) β subunit (anti-human β-TSH) was used to identify TSH cells in the pituitaries of five species of teleosts by means of the unlabeled antibody peroxidase-antiperoxidase (PAP) technique. The anti-human β-TSH reacted only with polygonal basophils located in the rostral pars distalis (RPD) in the pituitaries of sexually immature eel (Anguilla japonica). In the pituitaries of medaka (Oryzias latipes) and white-edged rockfish (Sebastes taczanowskii), this serum reacted specifically with only one cell-type located in the antero-dorsal proximal pars distalis (PPD) and antero-ventral PPD, respectively. In the pituitaries of two species of salmonids, sexually immature rainbow trout (Salmo gairdneri) and sexually mature chum salmon (Oncorhynchus keta), the anti-human β-TSH bound to the polygonal basophils in the ventral PPD adjacent to the RPD. Thus, the present immunocytochemical study identified polygonal basophils located in the RPD or PPD as TSH cells in five species of teleosts.
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