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  • Rat  (24)
  • Spektralphotometrie, Atomabsorption  (22)
  • Springer  (46)
  • 1995-1999
  • 1975-1979  (46)
  • 1945-1949
  • 1976  (46)
Collection
Publisher
  • Springer  (46)
Years
  • 1995-1999
  • 1975-1979  (46)
  • 1945-1949
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 171 (1976), S. 285-296 
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Castration ; Nuclear alterations ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the nuclei of epithelial cells of the dorsal lobe of the rat prostate were studied 2, 3, 5, 7 and 21 days after castration. The nucleolus appears to undergo a progressive disorganisation with partial fragmentation and dispersion of its normal components. Changes in the nucleoplasm were primarily reflected by a condensation of chromatin, particularly along the nuclear membrane and adjacent to the nucleolus. Later, different types of intranuclear inclusions were observed. After 21 days, the nuclei were characterized by an irregular outline with large indentation. Within the nucleoplasm aggregates of coarse granular chromatin were found. No cell necrosis was observed, indicating that androgen deprivation results in a remodeling of the cell to a less active state with marked cellular alterations and cessation of secretion, but apparently with some of their basic functions still intact. Injections of testosterone completely reverse the castrated-induced alterations. The changes observed are assumed to be due to the withdrawal of the androgenic stimulus, with a direct influence on the secretory function of the cell. The findings support the view that the stimulating secretory effect of androgen is mediated via an intranuclear androgen receptor, probably located in the nucleolus-associated-chromatin. It is also proposed that the secretory function of the epithelial cells of the prostatic complex, initiated by androgens, may be regulated by an intranuclear secretory center.
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  • 2
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    Cell & tissue research 173 (1976), S. 529-542 
    ISSN: 1432-0878
    Keywords: Capillaries ; Cerebral cortex ; Endothelial cells ; Intraendothelial lumen ; Interendothelial lumen ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Developing blood vessels in rat cerebral cortex were studied at a number of stages between 3 and 28 days postnatal, in an attempt to obtain data on the mechanisms by which the lumen is established within cords of mesodermal cells. A combination of techniques was utilized in an attempt to elucidate these mechanisms. These were: (a) aldehyde fixation and block staining with phosphotungstic acid; (b) aldehyde perfusion followed by perfusion of a lead solution and post-fixation in osmium tetroxide; (c) conventional preparation of tissue with aldehyde and osmium fixation. Support for interendothelial lumen formation was readily forthcoming, including vessels with junctions between two or more endothelial cells cut transversely. There was some support for intraendothelial lumen formation, in the form of “seamless” endothelial cells. Other features noted included the presence of free ribosomes and vacuoles in the endothelial cells, endothelial flaps, sprouts and tendrils, intraluminal debris, endothelial degeneration and a junction with a nonendothelial cell. Large numbers of endothelial vacuoles were noted, many of them occurring at the abluminal edge of the cells. These vacuoles may be involved in the formation of intraendothelial lumina and also in the enlargement of both types of lumina. This study provides evidence that besides the well-established inter-endothelial lumen formation, intraendothelial mechanisms may also be operative in rat cerebral cortex. The techniques employed in this study offer the potential for clarifying these and related issues.
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  • 3
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    Cell & tissue research 168 (1976), S. 261-270 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Exercise ; Rat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Four groups of male rats were exercised for periods of 2, 4, 6, and 8 weeks with controls in each group. As a result of chronic exercise there was an increase in the width of the zona fasciculata of the adrenal cortex. Also, there was an increase in the number and size of the mitochondria, and an increase in the quantity of smooth endoplasmic reticulum, and during the first 4 weeks of exercise an increase in the number of lipid droplets in the zona fasciculata. The close relationship between the smooth endoplasmic reticulum and the mitochondria, and the relationship between the smooth endoplasmic reticulum and the lipid droplets suggests a possible means for a transport mechanism for movement of precursors between these organelles.
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  • 4
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    Cell & tissue research 168 (1976), S. 303-314 
    ISSN: 1432-0878
    Keywords: Supraependymal cells ; Third ventricle ; Hypothalamus ; Hypophyseotropic area ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The supraependymal cells (SEC) are a normal component of the wall of the cerebral ventricles. In the hypothalamic area of the third ventricle they are restricted, in healthy animals, to the ependymal projection of the hypophyseotropic area. Here the SEC show great polymorphism. In addition to bipolar, multipolar and stellate or spider-like cells, transitional forms between these types can be seen. Their perikarya and processes can either remain at some distance from the ependyma or be in close contact with it. The processes may protrude between the ependymal cells or show surface differentiations that resemble the thin cytoplasmic folds of the mesenchymal wandering cells. Considering this and the variations in the number of cells, for example during the ovarian cycle, the SEC can be interpreted as mesenchymal cells, probably related to microglial cells of the subependymal layer. It is suggested that the SEC have a phagocytotic function and may be involved in the normal renewal of the ependyma. A definitive explanation for the restriction of the SEC to the hypophyseotropic area as well as the elucidation of their function remain to be found.
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  • 5
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    Cell & tissue research 168 (1976), S. 117-131 
    ISSN: 1432-0878
    Keywords: Retino-hypothalamic projection ; Suprachiasmatic nucleus ; Rat ; Axonal iontophoresis/cobalt precipitation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The technique of cobalt sulfide precipitation combined with Timm's sulfide-silver method for intensification of heavy metals was used to delineate the retino-hypothalamic projection of the rat. Freshly isolated rat brains were dissected and a solution of cobaltous chloride was applied to one of the cut optic nerves. Sixteen hours later, after cobalt ions had passed into the brain along the entire length of the optic fibers, the preparation was treated with ammonium sulfide to precipitate the cobalt as cobalt sulfide. In thick light microscopic sections, cobalt-filled axons were visualized as black fibers against a light gold background. Such fibers were observed to leave the posterior medial portion of the optic chiasm and, after arching dorsally, to project into the posterior fifth of the suprachiasmatic nucleus (SCN), as well as into the rostral part of the arcuate nucleus. Neither bifurcation of these axons nor looping of the axons back to the chiasm was seen. Most fibers projected to the SCN contralateral to the filled nerve, but the projection represented less than 0.1 % of the total number of fibers in one optic nerve. These observations are considered to be graphic evidence of a retino-hypothalamic projection. The interpretation of the cobalt method is discussed, as are the functions of the connections that have been observed.
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  • 6
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    Cell & tissue research 170 (1976), S. 43-60 
    ISSN: 1432-0878
    Keywords: Interdigitating cells ; Lymph node ; Rat ; Ultrastructure ; Cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electronmicroscopic and cytochemical studies were performed to localize interdigitating reticulum cells (IDC) in the popliteal lymph node of the rat. The morphological features of the IDC of the rat correspond to those described for other species, but also show similarities to normal macrophages in the rat. This is considered to be an argument in favour of the common origin of IDC's and macrophages. Ultrahistochemical studies with horseradish peroxidase (HRP) reveal no phagocytotic capacity of IDC's. After perfusion fixation containing ruthenium red (RR) the surface coat stains heavily: RR is also found deep in the membrane invaginations of the IDC, indicating the presence of polyanionic sialoglyco-proteins. The post-capillary-venules (PVC) are very permeable to both HRP and RR. The phosphotungstic acid-chromic acid stain (PTA-CrA) also reveals glycoproteins in the surface coat; these glycoproteins are susceptible to α-neuraminidase, whereas glycoproteins in the Golgi complexes, lysosomes and in the vesicular complexes of IDC are not. The glycoproteins of the latter are susceptible to 0.1 N NaOH. These findings indicate that IDC produce different kinds of glycoprotein, one of which may be secreted and act as a factor for stimulating peripheral T-lymphocytes. Intimate contact between IDC's and PCV's could be observed. It is therefore conceivable that IDC's play an important role in the homing of T-lymphocytes.
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  • 7
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Monoamine ; ZIO reaction ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The reaction of nerve endings in the median eminence of the rat to zinc iodide-osmium tetroxide (ZIO) staining was examined electron microscopically under normal and experimental conditions. The experimental condition of catecholamine exhaustion in the nerve endings was induced by the administration of H44/68 and reserpine. Vesicles in the terminals of catecholaminergic nerves reacted similarly to ZIO staining in both normal and experimental material. The majority of synaptic vesicles in various terminals gave a positive ZIO reaction. The neurosecretory elementary granules, however, failed to react with ZIO. On the other hand, some nerve terminals in the external layer of the median eminence showed a strong positive reaction in the cytoplasmic matrix, in mitochondria as well as in synaptic vesicles. These findings strongly suggest that the ZIO-positive substance in nerve terminals is not the transmitter itself, i.e. the monoamine, but rather represents a range of substances commonly found in various kinds of synaptic vesicles and is probably proteinaceous in nature. A brief discussion is also given on the difference in ZIO reactivity between neurosecretory elementary granules and small vesicles in the hypothalamo-hypophyseal tract.
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  • 8
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    Cell & tissue research 166 (1976), S. 407-412 
    ISSN: 1432-0878
    Keywords: Pituitary primordium ; Cytodifferentiation ; Rat ; Organ culture ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rathke's pouches isolated from rat fetuses on day 12 were maintained in organ culture for 9 days and investigated immunohistochemically to test whether or not the hypothalamus is involved in the cytodifferentiation of the adenohypophysis. The unlabeled antibody enzyme method demonstrated that the cultured tissue contains different types of glandular cells, i.e., adrenocorticotropin (ACTH)-, growth hormone (GH)-, luteinizing hormone (LH)-, thyrotropin (TSH)-, and prolactin-producing cells. Indirect evidence was also obtained to indicate the presence of melanocyte stimulating hormone (MSH)-cells. These findings suggest that adenohypophysial primordial cells of rats start to synthesize their respective hormones without stimuli from neurosecretory substances of the brain which are known to be essential for the maintenance of the secretory activity of the adult gland.
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  • 9
    ISSN: 1432-0878
    Keywords: Microtubules ; Tractus hypophyseus ; Diabetes insipidus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Evidence has already been adduced suggesting that an increase in microtubular number occurs in the tractus hypophyseus of rats stressed by the administration of hypertonic saline, and of rats with congenital diabetes insipidus (CDI). Since the tractus hypophyseus in these animals shows high secretory activity, it seems likely that the microtubular increase reflects the participation of microtubules in axoplasmic transport. To exclude, however, a congenital microtubular abnormality in CDI, affected newborn rats were examined. In these, the microtubular number was normal, thus suggesting that the increase in microtubular number seen in adult animals was not a congenital morphological abnormality. However, by 4 days of age there was a slight but statistically significant increase in microtubular number in affected rats, a change probably attributable to increased secretory activity.
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  • 10
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    Cell & tissue research 171 (1976), S. 375-379 
    ISSN: 1432-0878
    Keywords: Corpus luteum ; Autografts ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rat ovary has been transplanted successfully to subcutaneous tissue areas by several investigators. Light microscopy has revealed that corpora lutea in ovarian autografts are formed by luteinization of intact follicles and contain entrapped ova. In the present study, corpora lutea from autografted ovaries in castrate rats were obtained at metestrus and examined electron microscopically to determine whether their cellular morphology correlated with the normal progesterone levels in these animals. Cellular features usually accepted as regressive were apparent. The findings suggest either structural luteolysis is occurring before functional luteolysis or that the adrenal has increased steroidogenic activity in the castrate with ovarian autografts to account for the normal progesterone levels.
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  • 11
    ISSN: 1432-0878
    Keywords: Portal vein ; Rat ; Adrenergic innervation ; Postnatal ; Ontogenesis ; Histofluorescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The postnatal development of the adrenergic innervation pattern in the rat portal vein has been studied with the histochemical fluorescence method of Hillarp and Falck. Stretch preparations and transverse freeze-dried sections of intact portal veins were studied from rats during the first 5 weeks of life and from adult rats. Orientation of undifferentiated smooth muscle cells into two layers was observed at 4 days of age. Dominance of the thick outer longitudinal muscle layer was apparent at two weeks of age. A terminal adrenergic nerve plexus with some varicosities was restricted outside the media at the end of the first week. Ingrowth of penetrating non-terminal adrenergic nerve fibers through the longitudinal muscle layer occurred during the second week of age when the main terminal nerve plexus was developing between the two muscle layers. After 3 weeks of age the adult pattern of a two-dimensional adrenergic plexus between the muscle was established. In the adult rat pharmacological treatment with nialamide and noradrenaline revealed the thin, penetrating non-terminal adrenergic nerve fibers in the longitudinal muscle layer which were poorly visible otherwise. The present observations strongly indicate that the main adrenergic plexus between the two muscle layers emanates directly from the outer axonal plexus. These findings are discussed regarding possible trophic interactions between ingrowing sympathetic adrenergic vasomotor nerves and maturing vascular smooth muscle.
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  • 12
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    Cell & tissue research 172 (1976), S. 195-203 
    ISSN: 1432-0878
    Keywords: Spleen ; Rat ; Marginal sinus ; Marginal zone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The marginal sinus in the spleen of the Wistar rat surrounds the follicle and has more numerous PAS positive fibers on the inner wall than on the outer wall. India ink- and lead oxide-gelatin were injected into the abdominal aorta. It was found that much of the india ink-gelatin accumulated in the marginal sinus, the marginal zone, and part of the red pulp, while most of the lead oxide-gelatin collected in the marginal sinus. Ultrastructurally, the capillaries of the follicle were found to open into the marginal sinus. Regions not perforated by the marginal sinus lie between the follicle and the marginal zone. The wall of the marginal sinus is discontinuous and the discontinuities are wider on the marginal zone side than on the follicle side. The relationship of these findings is discussed.
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  • 13
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    Cell & tissue research 173 (1976), S. 1-15 
    ISSN: 1432-0878
    Keywords: Carotid body ; Rat ; Innervation ; Three-dimensional reconstruction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the carotid body of adult rats was studied by means of serial ultrathin sections. A single branching nerve fiber innervates 12 chief cells through several kinds of terminals (vesicle-containing, mitochondrial sack, and calyx-type) in en-passant and bouton forms. Two types of synaptic contacts between nerve terminals and chief cells are found; type 1 in which chief cells are postsynaptic, and type 2 in which chief cells are presynaptic. Since a single nerve fiber (possibly from the glossopharyngeal nerve) forms both types of synapses with type 2 predominating, the nerve fiber is considered basically sensory or centripetal. In addition to their synaptic connections with sensory nerve fibers, chief cells located in the periphery of this organ are in synaptic relation with dendrites of a few ganglion cells adjacent to these cells. Here the chief cells are presynaptic. A few synaptic contacts between two adjacent chief cells are seen, and so are direct contacts between chief cells and preganglionic efferent nerve fibers terminating on ganglion cells.
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  • 14
    ISSN: 1432-0878
    Keywords: Exocytosis, endocytosis ; Freeze-etching ; Electron microscopy ; Membrane particles, rosettes ; Neurohypophysis, neurosecretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Images have been obtained from freeze-etch replicas of neurohypophyses which are consistent with the view that orderly arranged aggregates of membrane particles occur in regions where fragments of membrane are being added to and taken away from the plasma membrane during secretion. Aggregates of particles included rosette-like and necklace-like patterns similar to those described by other authors at sites of exocytosis and endocytosis.
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  • 15
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    Cell & tissue research 165 (1976), S. 239-248 
    ISSN: 1432-0878
    Keywords: Superior cervical ganglion ; Rat ; Catecholamines ; Paraganglionic cells ; Monoamine synthesis inhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Monoamine storage sites in paraganglionic (PG-)cells of the rat superior cervical ganglion were investigated by electron and fluorescence microscopy following treatment with p-chlorophenylalanine (pCPA), disulfiram or guanethidine respectively. Dense core vesicles in PG-cells are significantly decreased (p〈 0.001) in number following pCPA, and in the majority of these cells following disulfiram and guanethidine. However in a minor portion of PG-cells the latter agents cause an increase in number and in size of dense core vesicles, in parallel with structural alterations. In agreement with these electron microscopic findings fluorescence microscopic and cytophotometric evaluations reveal a general decrease in catecholamine content with few cells showing an increase. The findings provide a morphological basis for the assumption, that monoamine storage sites in PG-cells can be decreased by inhibition of monoamine synthesis, following administration of pCPA, disulfiram and guanethidine. However the two types of responses of PG-cells which occur after disulfiram and guanethidine demonstrate a functional heterogeneity of this cell system in the rat superior cervical ganglion which is discussed.
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  • 16
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    Cell & tissue research 166 (1976), S. 135-143 
    ISSN: 1432-0878
    Keywords: Synaptic ribbons ; Pineal organ ; Rat ; Ultracytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The synaptic complexes of the rat pinealocytes are neither cholinergic nor adrenergic. In the synaptic vesicles, a neurotransmitter carrier substance of lipid nature reacting with OsO4-Zn I2 mixture (similar to that present in both cholinergic and adrenergic vesicles) was not found. In addition, there were no indications of glucose-6-phosphatase or thiamine-pyrophosphatase activity in the synaptic vesicles. Thus, it appears that the synaptic vesicles do not originate from the rough or smooth endoplasmic reticulum. The synaptic ribbons do not contain carbohydrates, are of protein nature and possess some chemical resemblance to microtubules and microtubular bouquets. Appropriate ultracytochemical reactions have not shown detectable quantities of sodium and calcium ions in pinealocyte synaptic complexes.
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  • 17
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    Cell & tissue research 168 (1976), S. 411-418 
    ISSN: 1432-0878
    Keywords: Luteinizing hormone-releasing hormone ; Hypothalamus ; Rat ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of radioactivity in the rat hypothalamus after intraventricular injection of tritiated luteinizing hormone-releasing hormone (LH-RH) was studied by autoradiography and compared with that expected from Fick's second law which defines the character of ordinary diffusion. The results suggest that LH-RH penetrates through the ependyma and thin subependymal layer in the median eminence and into the suprachiasmatic area by ordinary diffusion. By contrast, concentration of radioactivity in outer layers of the median eminence is increased and, therefore, can not be explained by the diffusion law. In this region incorporation of radioactivity into cell bodies was demonstrated. In the subependymal layer of the median eminence a few rows of silver grains seemingly located in cellular processes were also observed. The diffusion coefficient in the periventricular zone was lower than that in the deeper tissue. It is suggested that the ependymal-subependymal complex of the third and lateral ventricles acts as a passive membrane towards LH-RH contained in the cerebrospinal fluid. The significance of this mechanism for the intrahypothalamic transport of RHs is discussed.
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  • 18
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    Cell & tissue research 168 (1976), S. 549-559 
    ISSN: 1432-0878
    Keywords: Hypothalamic-hypophysial-adrenal axis ; Rat ; Development ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenal glands of decapitated and encephalectomized fetal rats were investigated electron microscopically and compared to those of normal intact fetal rats. Although the adrenal cortices did not show three zones (zona glomerulosa, fasciculata, and reticularis) on the 16.5th day of gestation when the decapitation or encephalectomy was carried out in utero, the zonation was recognized in fetuses operated on the 21.5th day of gestation. The same was true for normal control fetuses. However, cytoplasmic characteristics suggesting steroidogenesis in the cortical cells were reduced to various degrees in the encephalectomized or decapitated fetuses, especially in the latter ones. The change in cytoplasmic appearance was more conspicuous in the inner portion of the cortex. This result suggests that for the maintenance of normal adrenocortical function the hypothalamus may be indispensable even during the prenatal life of rats.
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  • 19
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 100-101 
    ISSN: 1618-2650
    Keywords: Best. von Spurenelementen, Mangan, Kobalt in Serum ; Spektralphotometrie, Atomabsorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 20
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 205-205 
    ISSN: 1618-2650
    Keywords: Best. von Schwermetallen in Wasser, Biolog. Material ; Spektralphotometrie, Atomabsorption ; verbesserter Gas-stop
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 21
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    Fresenius' Zeitschrift für analytische Chemie 278 (1976), S. 121-124 
    ISSN: 1618-2650
    Keywords: Best. von Titan ; Spektralphotometrie, Atomabsorption ; Einfluß von Wertigkeit, Säuren, Liganden
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Der Einfluß der Wertigkeit des Titans, von Mineralsäuren und von verschiedenen organischer Komplexliganden auf die Ti-Absorption in N2O-Acetylen-Flammen wurde ausführlich untersucht. Die thermischen Prozesse in den trockenen Aerosolpartikeln scheinen für die Atomisierung wichtiger zu sein, als die Komplexbildungsgleichgewichte in der Lösung. In Gegenwart von Chromotropsäure ist die Titanbestimmung mit AAS empfindlicher und selektiver als bei der bisherigen Ausführung.
    Notes: Abstract The atomic absorption method for the determination of titanium in N2O-acetylene flames is studied from the point of view of the valence state of titanium, the effect of mineral acids and various organic complexing ligands in solution. It seems evident that the thermal procedures within the dry aerosol particle are rather more deciding for the atomisation processes than the complexation equilibria in solution. In the presence of chromotropic acid the sensitivity and selectivity of the method are increased in comparison with the usual procedure in pure solutions.
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  • 22
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    Cell & tissue research 173 (1976), S. 179-191 
    ISSN: 1432-0878
    Keywords: Epiglottis ; Rat ; Elastic cartilage ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Chondrocytes of the rat epiglottis contain large amounts of glycogen and lipids, which often make the cells resemble fat cells. The content of lipids is interpreted as being related to the function of the cells. The membranes of some of the large vacuoles are stained with ruthenium red. The cells give rise to long cytoplasmic processes. As in hyaline cartilage the intercellular substance consists of a fine network containing proteoglycan granules together with thicker cross striated fibers. Furthermore elastic fibers are found, consisting of amorphous and microfibrillar parts. In the matrix, both lysosome-like granules and more or less empty vesicles are observed. Accumulations of a finely particulate electron dense material and of a translucent amorphous material containing membrane bound granules are found in some lacunae situated in the outer part of the cartilage. These accumulations are possibly related to the development of collagenous and elastic fibers.
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  • 23
    ISSN: 1432-0878
    Keywords: Liver ; Rat ; Sinusoid ; Pit cell ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pit cells — a new type of cell first described here and so named because they contain highly characteristic granules — are situated in the wall of rat liver sinusoids, and have hyaloplasmic pseudopodia intermingling with the microvilli of the parenchymal cells. The characteristic granules are mainly situated at one side of the nucleus, the other side showing organelle-free hyaloplasm. Pit cells are also found in portal tracts and in granuloma-like cellular aggregates. They also occur in rat peripheral blood, although there are morphological differences between cells in these two sites. Pit cells can be regarded as regular inhabitants of the sinusoidal wall, and therefore belong to the series of sinusoidal cells, i.e., the endothelial (Wisse, 1972), Kupffer (Widmann et al., 1972; Wisse and Daems, 1970; Wisse, 1974a,b), and fat-storing cells (Ito, 1973). Pit cells do not phagocytose and do not react to a great number of experimental conditions, to which endothelial and Kupffer cells do react (Wisse, 1972, 1974b). Mitosis has been observed in a pit cell. The function of pit cells remains obscure, but an endocrine function is suggested by the morphology of their highly characteristic granules.
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  • 24
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    Cell & tissue research 173 (1976), S. 543-554 
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Dog ; Basal cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the basal cells of rat lateral and ventral prostate and of dog prostate has been studied. Basal cells from both species appear as undifferentiated cells, characterised by a lack of cytoplasmic organelles and a poorly developed Golgi complex and endoplasmic reticulum. The presence of cytoplasmic filaments and micropinocytosis is not considered to be sufficient evidence to assume any similarity to myoepithelium, as has been previously suggested. Basal cells are instead considered to be precursors of secretory epithelial cells.
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  • 25
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    Cell & tissue research 174 (1976), S. 83-97 
    ISSN: 1432-0878
    Keywords: 6-hydroxydopamine ; Extraneuronal effects ; Rat ; Adrenal ; Tissue culture ; Electron microscopy ; Microspectrofluorimetry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of various concentrations of 6-hydroxydopamine (6OHDA) on rat adrenocortical cells in tissue culture were studied with phase contrast and electron microscopy. With 40 mg/l of 6-OHDA the first signs of alteration as revealed by microcinematography appeared in isolated cortical cells as early as 15 min after addition of the drug. There was a cessation of movement of cell organelles and an immobilisation of membrane undulations followed by the development of dark inclusion bodies. The cells underwent increasing shrinkage and collapsed by 11/2 h. Chromaffin cells were not affected until 45 min after exposure to the drug and neurons were the most resistant population. However 61/2 h after application of the drug most cells in the culture were dead. 6-OHDA applied in different doses and to adrenal expiants did not alter the sequence of events. Ultrastructurally cortex cells underwent damage along two lines: they either showed lytic changes or developed various types of dense bodies before reaching the lytic stage. Treatment of cortical cells with 40 mg/l 5-or 6-OHDA followed by exposure to buffered 2% glyoxylic acid and heat did not produce a fluorescence within the cells. Microspectrofluorimetry on amine models with noradrenaline, 5- and 6-OHDA revealed that neither 5-nor 6-OHDA are capable to form a fluorophore with glyoxylic acid.
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  • 26
    ISSN: 1432-0878
    Keywords: Ovarian autografts ; Autonomic innervation ; Ovarian steroids ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ovaries were removed from female rats and immediately autografted into a subcutaneous pouch in the flank in order to quantitate the relationship of graft re-innervation, steroid secretion and vaginal smear pattern. Animals were killed at three time periods: three days after grafting, on the first day a cornified vaginal smear appeared and at the first metestrus. In addition, control animals were killed at metestrus. Plasma samples were obtained from all rats and analyzed for estradiol-17β and progesterone concentration by radioimmunoassay. At the first day of vaginal cornification after grafting, plasma estradiol-17β (45.8±4.0 pg/ml) was elevated in comparison to controls at metestrus (24.0±2.6 pg/ml), but plasma progesterone (21.5±4.0 ng/ml) was not different (30.6±1.7 ng/ml). Subsequently, at the first metestrus following grafting, plasma estradiol-17β (23.0±3.5 pg/ml) was comparable to control values. In contrast, progesterone was decreased (17.5±1.9 ng/ml). A definite correlation was detected between the vaginal smear and plasma levels of steroid hormones in the castrated female rat with subcutaneous ovarian autografts. Histochemical techniques were used to study the adrenergic and cholinergic innervations of grafts three days after grafting, at the first day of vaginal cornification, and at the first metestrus. No correlation was shown between density of adrenergic or cholinergic innervation and plasma levels of estradiol-17β and progesterone or onset of a cycling vaginal smear.
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    Cell & tissue research 172 (1976), S. 133-144 
    ISSN: 1432-0878
    Keywords: Cornea ; Nerves ; Rat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the corneal nerves of the rat was studied in tissue fixed by immersion in and by perfusion with glutaraldehyde-containing fixatives. Of the four types of axonal terminal identified in the nerves, those with the features of adrenergic and cholinergic terminals were confined to the nerves at the limbus and were concentrated in the perivascular plexuses. The remaining two types of terminal were found on axons located in all parts of the cornea and on both intraepithelial axons and axons in the stromal nerves. Of these, one contained the numerous mitochondria which occur in the terminals of axons associated with known mechanoreceptors and the second contained variable and often small numbers of both clear and large dense-cored vesicles. While most of the mitochondria-containing terminals were seen in nerves located near the periphery, vesicle-containing terminals were numerous in all of the nerves, and especially in those in the avascular cornea. In material fixed by immersion in glutaraldehyde-paraformaldehyde, the vesicle-containing terminals appeared to be dilated, but in material fixed by perfusion there was little evidence of any increase in the diameter of the axons in the terminal regions. The structure of the terminals was compared with that of the terminals of axons identified in the nerves of the skin and the urinary tract and the differences in the vesicle content of the terminals to those reported in other studies of the corneal nerves was related to the use of different fixation procedures. The possibility that axons possessing such terminals are identical with the beaded axons and both the cholinesterase-positive and fluorescent axons demonstrated in light microscopical studies of the corneal nerves is discussed, and the widespread distribution of the axons in the cornea is equated with the hypothesis that they are afferent in nature and represent the peripheral receptors for pain impulses.
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 103-104 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie, Atomabsorption ; Graphitrohröfen, Präzision u. Richtigkeit
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 23-27 
    ISSN: 1618-2650
    Keywords: Analyse von Kupfer, Kupfersalzen ; Spektralphotometrie, Atomabsorption ; Ausfällen der Matrix als CuS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur Bestimmung der Elementspuren Cd, Co, Fe, In, Mn, Ni, Pb, Tl und Zn in reinem Kupfer und Kupfersalzen wird die Matrix als CuS mit Thioacetamid als Fällungsreagens ausgefällt. In 3 N salzsaurer Lösung werden die Elemente mit Ausbeuten ≥ 90 %, Tl zu 75 %, im Filtrat wiedergefunden. Nach Zusatz von HNO3 und Einengen des Filtrats, erhält man ein praktisch rückstandsfreies Spurenkonzentrat, in dem die angereicherten Elemente durch Flammen-Atomabsorptions-Spektrometrie bestimmt werden. Die relative Standardabweichung s/¯x liegt im allgemeinen bei Werten um 0,03. Für Einwaagen von 1 g Kupfer werden Nachweisgrenzen erzielt, die, je nach Element, zwischen 0,2 und 3 ppm liegen.
    Notes: Abstract For the determination of traces of elements such as Cd, Co, Fe, In, Mn, Ni, Pb, Tl and Zn in pure copper and copper salts the matrix is precipitated as CuS using thioacetamide as precipitating reagent. In solutions containing 3 N hydrochloric acid, the recovery of the elements is ≥90 % (Tl 75%). By addition of HNO3 and evaporation of the filtrate to dryness a trace concentrate is received which is practically free of a salt residue and in which the preconcentrated elements are determined by flame AAS. The relative standard deviation s/¯x is generally about 0.03. Using samples of 1 g of copper the limit of detection for different elements was found to be between 0.2 and 3 ppm.
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 288-288 
    ISSN: 1618-2650
    Keywords: Best. von Arsen in Wasser ; Spektralphotometrie, Atomabsorption ; flammenlos, Müllsickerwasser
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 337-345 
    ISSN: 1618-2650
    Keywords: Best. von Cadmium in Bleidioxid, Vanadiumpentoxid, Uranoctoxid ; Spektralphotometrie, Atomabsorption ; Laserverdampfung, Rasteranalyse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine flammenlose Methode für die AAS wird beschrieben, die zur Mikro- und Lokalanalyse von Festkörpern eingesetzt werden kann. Die Verdampfung ausgewählter Probenbereiche erfolgt mit einem Ionen-Dauerstrichlaser. Die Cadmiumgehalte in V2O5-, PbO2- und U3O8-Proben, die unterschiedliche Cadmiumkonzentrationen enthalten, werden bestimmt. Die verdampfte Substanzmenge pro Messung beträgt ca. 1 μg, die aus einer Probenfläche von ca. 0,008 mm2 erhalten wird. Die Empfindlichkeit für die Cadmiumbestimmung beträgt 2,1 · 109 g Cd/1% Absorption und die Nachweisgrenze 4,8 · 10−10 g Cd. Als ein Anwendungsbeispiel folgt die Beschreibung und Auswertung einer Mikrorasteranalyse: von einer 14 mm2 Probenfläche wird aus 57 Einzelmeßwerten ein Konzentrationsprofil des Dotierungselementes ermittelt. Dafür werden zwei graphische Darstellungen vorgeschlagen. Vorteile des Verfahrens werden durch Vergleich mit bisher bekannten Techniken erläutert.
    Notes: Abstract A flameless method for AAS is described, which can be used for micro- and local analysis of solid samples. The evaporation of chosen areas of the sample is achieved with a continuous wave ion laser. The evaporated mass of each measurement is about 1 μg, which comes from an area of 0.008 mm2 from the surface of the specimen. The cadmium contents of samples of vanadium, lead and uranium oxides containing different concentrations of cadmium were determined. The sensitivity of the cadmium analysis is 2.1 · 10−9 g of Cd/1% absorption and the detection limit is found to be 4.8 · 10−10 g of cadmium. The description and interpretation of a raster microanalysis as an application of this method follows: 57 point measurements from an area of 14 mm2 are used to construct concentration contours of the doping element. Two graphic representations are suggested. The advantages of this method are compared with other known techniques.
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 347-349 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie, Atomabsorption ; ohne Wägung, auf See
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Um das auf See problematische Einwiegen von Erzproben zur Analyse durch Atomabsorptions-Spektrometrie zu umgehen, wird eine indirekte Ermittlung der eingesetzten Probemenge durch die Bestimmung eines „Leitelementes“ mittels Isotopfluorescenzanalyse erprobt. Am Beispiel von Manganknollen des Pazifischen Ozeans, die 15–30% Mn, 0,5–1,5% Ni und Cu enthalten, wird gezeigt, daß sich die beiden zuletzt genannten Elemente auf diese Weise mit einer Genauigkeit von besser als 10% rel. bestimmen lassen.
    Notes: Abstract The weighing of ore samples to be analyzed by atomic absorption spectrometry is somewhat problematical at sea. To evade the weighing, tests have been made to try out an indirect determination of the mass of the sample by determining a “reference element” by means of isotope fluorescence analysis. The analysis of manganese nodules from the Pacific Ocean, containing 15–30% of Mn and 0.5–1.5% of Ni and Cu, is quoted as an illustration. It has been shown that the two latter elements can be determined in this way with an accuracy of at least 10% rel.
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    Fresenius' Zeitschrift für analytische Chemie 278 (1976), S. 97-103 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie, Atomabsorption ; vereinfachte Additionsmethode, Korrekturprogramm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Ein vereinfachtes Verfahren der Additionsmethode in der Atomabsorptionsspektrometrie wird beschrieben. Bei diesem vereinfachten Verfahren werden die Bestimmungen sämtlicher Elemente in einer einzigen Probe durchgeführt. Die Auswertung und die dazu notwendigen Korrekturen werden mit Hilfe eines Computerprogramms vorgenommen. Das beschriebene Verfahren liefert gute Ergebnisse bei geringem Arbeitsaufwand.
    Notes: Abstract With this simplified method all determinations of all the elements are carried out in only one probe. The errors are corrected by a computer program. With the method described good results can be obtained with little expenditure of work.
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  • 34
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    Fresenius' Zeitschrift für analytische Chemie 278 (1976), S. 115-120 
    ISSN: 1618-2650
    Keywords: Verwendung von Glykolmethacrylat zur Spurenanalyse ; Gele mit Hydroxychinolin ; Best. von Kupfer, Eisen, Mangan, Blei in Ammoniumfluorid ; Spektralphotometrie, Atomabsorption ; flammenlos, Glykolmethacrylatgel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Hydrophile makroporöse Copolymere von Glykolmethacrylat mit Glykolmonomethacrylat mit über eine Azogruppe gebundenem 8-Hydroxychinolin zeichnen sich durch eine rasche Gleichgewichtseinstellung bei Austauschprozessen aus (2–5 min). Die Sorptionsisothermen von Pb2+ und Cu2+ wurden gemessen (Sorptionsvermögen 0,2–0,3 mMol Me/g). Die Verteilungskoeffizienten für Pb2+ und Cu2+ sinken von etwa l05 auf 102 bei 90% iger Sättigung. Die Anwendung von Mikrokolonnen (0,02 ml Gesamtvolumen des Austauschers) zur Abtrennung und Anreicherung von Schwermetallspuren in ng-Mengen für die nachfolgende flammenlose Atomabsorption wurde vorgeschlagen. Als Beispiel wird die Bestimmung von Cu, Fe, Mn und Pb (5×10−7–5×10−5%) in Ammoniumfluorid beschrieben.
    Notes: Abstract Hydrophilic macroporous glycolmethacrylate-glycolmonomethacrylate copolymers with 8-hydroxyquinoline, bound via the azo-group, possess a high equilibration rate for exchange processes (2–5 min). The sorption isotherms of Pb2+ and Cu2+ have been studied (sorption capacity of 0.2–0.3 mMol · g−1. The partition coefficients for Pb2+ and Cu2+ (about 105 for unsaturated exchanger) are lowered in dependence of the exchanger saturation (about 102 for 90% saturation). The use of microcolumns (total volume of the exchanger 0.02 ml) for the separation and enrichment of traces of heavy metals in ng-amounts for the subsequent flameless atomic absorption spectroscopy is proposed. The determination of Cu, Fe, Mn and Pb (5×10−7 to 5x10−5%) in a high purity ammonium fluoride is described as an example.
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    Fresenius' Zeitschrift für analytische Chemie 281 (1976), S. 103-107 
    ISSN: 1618-2650
    Keywords: Best. von Platin ; Spektralphotometrie, Atomabsorption ; Einfluß von Pd, Rh
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die AAS-Bestimmung von Platin wird von zahlreichen Elementen zum Teil sehr stark gestört. Durch Zusatz von Uran kann der Einfluß von Palladium und Rhodium mit Hilfe quadratischer Korrekturgleichungen beseitigt werden. Lanthan ist als Puffer ungeeignet.
    Notes: Abstract There are a number of serious interferences in the determination of platinum by atomicabsorption spectrometry. The influences of palladium and rhodium have been investigated. It is shown that they can be eliminated by an addition of uranium and by quadratic correction equations. Addition of lanthanum is not suitable.
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    Fresenius' Zeitschrift für analytische Chemie 281 (1976), S. 299-299 
    ISSN: 1618-2650
    Keywords: Best. von Silber in Kupfer ; Spektralphotometrie, Atomabsorption ; Extraktion
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    Fresenius' Zeitschrift für analytische Chemie 281 (1976), S. 291-294 
    ISSN: 1618-2650
    Keywords: Best. von Rhodium ; Spektralphotometrie, Atomabsorption ; Einfluß von Pt und Pd
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Beeinflussung der atomabsorptionsspektroskopischen Rhodiumbestimmung ist gering. Verglichen mit den Elementen Pt und Pd sind die Meßwerte bei Abwesenheit von Fremdionen am genauesten. Der Zusatz von Uran oder Lanthan als spektroskopische Puffer erhöht die Empfindlichkeit. Der von Palladium und Platin verursachte Störeinfluß kann nicht mit quadratischen Korrekturgleichungen eliminiert werden. Zur Unterdrückung des Einflusses eignet sich Uran als Puffersubstanz am besten. Mit dem Pufferzusatz kann der verbleibende Einfluß mit Korrekturgleichungen korrigiert werden.
    Notes: Summary The influence on the determination of rhodium is only slight. In comparison with the elements Pt and Pd the measurements are most exact in the absence of foreign ions. Addition of uranium or lanthanum as spectroscopic buffers causes an increase in sensitivity. The interfering effects of palladium and platinum cannot be eliminated by correcting equations. However, with the addition of uranium as a buffer the effects are minimized and the remaining influence can be corrected by means of equations.
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    Fresenius' Zeitschrift für analytische Chemie 281 (1976), S. 300-300 
    ISSN: 1618-2650
    Keywords: Best. von Zink, Cadmium, Wismut in Kupfer ; Spektralphotometrie, Atomabsorption ; Extraktion
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  • 39
    ISSN: 1618-2650
    Keywords: Best. von Arsen, Antimon, Selen ; Spektralphotometrie, Atomabsorption ; Vergleich d. Reduktion mit Zn/SnCl2/KJ oder NaBH4
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary An atomic-absorption spectrophotometric method for the rapid and sensitive determination of arsenic, antimony, and selenium with the hydride-argon/hydrogen flame system has been studied. The comparison of the zinc tablet combined with stannous chloride and potassium iodide, and the sodium borohydride tablet reduction systems are described. The sensitivities and precisions of both reduction systems are estimated to be nearly the same. From the results of the comprehensive study on interferences, the zinc system is concluded to be more selective than the sodium borohydride system, which is especially true for arsenic.
    Notes: Zusammenfassung Ein atomabsorptionsspektralphotometrisches Verfahren zur raschen und empfindlichen Bestimmung von Arsen, Antimon und Selen über ihre Hydride unter Verwendung der Argon-Wasserstoff-Flamme wurde im Hinblick auf die Reduktionssysteme untersucht. Die Verwendung von Zinktabletten in Kombination mit Zinn(II)-chlorid und Kaliumjodid sowie von Natriumborhydridtabletten wurde geprüft und gefunden, daß in bezug auf Empfindlichkeit und Reproduzierbarkeit keine nennenswerten Unterschiede bestehen. Das Zinksystem bietet jedoch eine bessere Selektivität, besonders im Falle von Arsen.
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    Fresenius' Zeitschrift für analytische Chemie 282 (1976), S. 21-23 
    ISSN: 1618-2650
    Keywords: Analyse von Cadmium ; Spektralphotometrie, Atomabsorption ; Anreicherung der Spuren durch partielles Lösen der Matrix
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Aus Reinst-Cadmium können durch partielles Lösen der Matrix die Elementspuren Ag, Au, Bi, Co, Cu, Fe, In, Ni, Pb, Pd und Sn angereichert werden. Dazu werden die Proben mit einem dünnen Quecksilberfilm überzogen und in Bromwasserstoffsäure bis auf einen kleinen Rest gelöst. Die im Löserückstand angereicherten Spuren werden durch Atomabsorptions-Spektrometrie bestimmt. Die relativen Standardabweichungen betragen etwa 0,05; die Anreicherungsausbeuten sind 〉 95%. Bei Einwaagen von 10 g Cadmium beträgt der Anreicherungsfaktor etwa 102; die Nachweisgrenzen (3σ-Grenzen) liegen um 0,1 ppm. Der Einfluß der Lösebedingungen auf die Anreicherung wird diskutiert.
    Notes: Abstract Trace elements such as Ag, Au, Bi, Co, Cu, Fe, In, Ni, Pb, Pd, and Sn can be preconcentrated from high-purity cadmium by partial dissolution of the matrix. The samples are coated by a thin film of mercury and dissolved in hydrobromic acid up to a small residue. In this residue the trace elements are enriched with recoveries of more than 95%. The elements are determined by AAS. For 10 g Cd the factor of enrichment is about 102, and the limits of detection are in the range of 0.1 ppm. The relative standard deviation was calculated to be about 5%. Reasons influencing the recovery of the trace elements are discussed.
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    Fresenius' Zeitschrift für analytische Chemie 282 (1976), S. 119-121 
    ISSN: 1618-2650
    Keywords: Best. von Chrom ; Spektralphotometrie, Atomabsorption ; Einfluß der Wertigkeit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Intensität des flammenabsorptionsspektrometrischen Cr-Signals hängt in einer sehr komplexen Weise von der Wertigkeit des Chroms und der Flammentemperatur ab. Ferner ist ein ausgeprägter Kalium-Einfluß vorhanden. Alle diese Schwierigkeiten können am besten dadurch eliminiert werden, daß in der Lachgasflamme gearbeitet und die Analysenlösung mit einer höheren K-Konzentration „gepuffert“ wird.
    Notes: Abstract The intensity of the chromium signal in AAS depends in a very complex manner strongly on the valency of the Cr and the flame temperature. It is furthermore influenced by potassium, if present. The best way to overcome all these interferences is to use the nitrous oxide flame and to “buffer” the solution with a higher concentration of potassium.
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  • 42
    ISSN: 1618-2650
    Keywords: Best. von Arsen als Hydrid ; Spektralphotometrie, Atomabsorption ; Maskierung von Störungen mit KJ
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 102-103 
    ISSN: 1618-2650
    Keywords: Best. von Natrium, Kalium ; Spektralphotometrie, Flammenemission ; Best. von Calcium, Magnesium ; Spektralphotometrie, Atomabsorption
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    Fresenius' Zeitschrift für analytische Chemie 279 (1976), S. 351-354 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie, Atomabsorption ; Optimierung von Meßbedingungen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eingehende Untersuchungen zeigen, daß die Leistungsfähigkeit der Atomabsorptionsspektroskopie gewöhnlich nicht optimal genutzt wird. Der Einfluß wesentlicher Größen, wie Viscosität, Temperatur, Salzkonzentrationen, Oberflächenspannung usw. wird untersucht bzw. anhand der Hagen-Poiseuilleschen Gleichung diskutiert.
    Notes: Abstract Detailed tests have been made to show the efficiency of a modern atomic absorption spectrometer. The influence of different parameters as: viscosity, temperature, concentration of salts, surface tension etc., is discussed on the basis of Hagen-Poiseuille's equation.
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    Fresenius' Zeitschrift für analytische Chemie 280 (1976), S. 359-364 
    ISSN: 1618-2650
    Keywords: Best. von Palladium neben Platin, Rhodium ; Spektralphotometrie, Atomabsorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die atomabsorptionsspektroskopische Palladiumbestimmung wird vom Platin nicht und vom Rhodium nur wenig beeinflußt. Berücksichtigt man, daß ein Zusatz von Uran die Palladiumbestimmung neben Rhodium desaktiviert, so liegen allgemein die günstigsten Bedingungen für die Palladiumbestimmung vor, wenn Lanthan als spektroskopischer Puffer zugesetzt wird. Korrekturgleichungen werden gegeben.
    Notes: Abstract The atomic-absorption determination of Pd is not affected by Pt, but there is a small influence by Rh. The aim of this investigation is to determine these effects quantitatively, furthermore under the releasing effects of uranium and lanthanum. Equations to correct the results are given.
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    Fresenius' Zeitschrift für analytische Chemie 278 (1976), S. 203-206 
    ISSN: 1618-2650
    Keywords: Best. von Blei, Cadmium in Wein ; Spektralphotometrie, Atomabsorption ; Extraktionsmethode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The insolubility of sugars and fruit acids in MIBK allows the direct extraction of heavy metals by APDC from wine and similar products. With special precautions an accuracy of /+-5% can be obtained for Pb and Cd in the concentration range from 0.1–1 ppm and 1–10 ppb, respectively. Together with our experiences a brief survey of the most recent literature is also presented.
    Notes: Zusammenfassung Die Unlöslichkeit der Zucker und Fruchtsäuren in MIBK erlaubt die Direktextraktion von Schwermetallionen mittels APDC aus Wein und ähnlichen Produkten. Unter Beachtung besonderer Vorsichtsmaßnahmen wird für Pb im Bereich von 0,1–1 ppm und für Cd im Bereich 1–10 ppb eine Genauigkeit von ± 5% erhalten. Gleichzeitig wird zusammen mit unseren Erfahrungen ein kurzer Überblick über die neueste Literatur gegeben.
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