bluuebunny/crossref_metadata_2025_split huggingface dataset:
Horizontal cells of the turtle retina. II. Analysis of interconnections between photoreceptor cells and horizontal cells by light microscopy
Authors: Leeper Harold F. 
Published: December 2004

AbstractCriteria were established whereby the chief and accessory members of double cones, red‐, green‐, and blue‐sensitive single cones, and rods could be distringuished form one another in 1‐μm sections through the retinas of Pseudemys scripta elegans and Chelydra serpentina. Criteria included the presence or absence of an oil droplet, the size, color, and radial position of the oil droplet, the size and shape of the inner and outer segments, and the shape and orientation of the connection between the perikaryon and synaptic terminal of each receptor cell.Using these criteria, the color‐specific interconnections between horizontal cells and receptor cells were analyzed using 1‐μm serial sections through Golgistained examples of horizontal cells of each type. The results of this analysis area:
H1 cell bodies contact both the red‐ and green‐sensitive members of double cones, as well as red‐ green‐sensitive single cones.
H1 aoxn terminals contact only the red‐sensitive chief members of doulbe cones, red‐sensitive single cones, and rods.
H2‐type cells contact only green‐ and blue senstive single cones.
H2‐type cells contact only blue‐sensitive single cones.
H2‐type cells contact only green‐sensitive accessory members of double cones.
With the exception of H1 cell bodies, all horizontal cells generally contacted every apporpriate receptor cell type within their receptive field. A model for the generation of complex horizontal cell light responses is proposed and discussed.
Postnatal changes in the number of astrocytes, oligodendrocytes, and microglia in the visual cortex (area 17) of the macaque monkey: A stereological analysis in normal and monocularly deprived animals
Authors: O'Kusky John , Colonnier Marc 
Published: December 2004

AbstractThe numerical densities (Nv) of astrocytes, oligodendrocytes, and microglia were measured in indvidual laminae of the striate cortex of macaque monkeys ranging in age from newborn to adult. Using measurements of cortical thickness and surface area, the total number of cells in the striate cortex of one hemisphere was derived for each glial cell type. Normal monkeys were compared at 3 months and 6 months of age to animals reared from birth with a monocular eyelid suture. No significant differences were observed between normal and monocularly deprived monkeys. The combined data from these groups, however, demonstrated several significant developmental changes. The Nv of astrocytes decreased from birth to 6 months of age and susequently increased in the adult. The greatest changes were seen in the more superficial laminae. These changes, however, were only a response to a substantial overshoot in cortical volume at six months: the total number of astrocytes in the striate cortex did not change. There was a tenfold increase in both the Nv and the total number of oligodendrocytes from birth to maturity with a corresponding increase in the density of myelinated axons. The greatest changes were observed in the deeper laminae. The total number of microglia remained relatively constant from birth to 6 months of age. There was a 55% reduction in the number of microglia in the adult, although statistical analysis indicated that this decrease was only of borderline significance. The possible relationships between these postnatal changes in glial cell numbers and the development of neuronal connectivity are discussed.
Electrophysiologic studies of cutaneous nerves of the forelimb of the cat
Authors: Kitchell R. L. , Canton D. D. , Johnson R. D. , Maxwell S. A. 
Published: December 2004

AbstractThe cutaneous innervation of the fo relimb was investigated in 20 bar‐biturate‐anesthetized cats by using electrophysiological techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least six cats by brushing the hair in the CA with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed larger overlap zones (OZ) than were noted in the dog. Remarkable findings were that the brachiocephalic nerve arose from the axillary nerve and the CA comparable to that supplied by the cutaneous branch of the brachiocephalic nerve in the dog was supplied by a cutaneus branch of the suprascapular nerve. The CA supplied by the communicating branch from the musculocutaneous to the median nerve was similar in both species except that the communicating branch arose proximal to any other branches of the musculocutaneous nerve in the cat, whereas it was a terminal branch in the dog. The superficial branch of the radial nerve gave off cutaneous brachial branches in the cat proximal to the lateral cutaneous antebrachial nerve. The CA of the palmar branches of the ulnar nerve did not completely overlap the CA of the palmar branches of the median nerve as occurred in the dog; thus an autonomous zone (AZ) for the CA of the palmer branches of the median nerve is present in the cat, whereas no AZ existed for the CA of this nerve in the dog.
A quantitative study of the thalamocortical and other synapses in layer IV of pyramidal cells projecting from mouse SmI cortex to the caudate‐putamen nucleus
Authors: Hersch Steven M. , White Edward L. 
Published: December 2004

AbstractThe thalamocortical and other synapses of the apical dendrites of corticostriatal projection neurons in mouse primary somatosensory cortex (SmI) were examined by combining anterograde degeneration with the retrograde transport of horseradish peroxidase (HRP). Electrolytic lesions were made in the ventrobasal thalamus, followed 3 days later by injections of 40% HRP into the ipsilateral caudate‐putamen nucleus. The next day, the mice were perfused and the SmI cortex ipsilateral to the lesion and injection sites was chopped at 125‐μm and reacted for HRP using a CoCl2‐DAB method. HRP‐labeled corticostriatal cells in SmI cortex were medium‐sized pyramidal cells, having somata located in the superficial portion of layer V and apical dendrites extending into layer I. Seven corticostriatal cells were serially thin sectioned and the layer IV portions of their apical dendrites were reconstructed. Each apical dendrite formed only one or two thalamocortical synapses (0.3 to 0.9% of their synapses in layer IV) indicating that corticostriatal neurons may be minimally responsive to direct synaptic input from the specific thalamic nuclei. Each apical dendrite formed about 12.6 asymmetrical synapses for every symmetrical synapse, suggesting that the relative numbers of excitatory and inhibitory synapses impinging on apical dendrites belonging to an individual class of neurons may be specified.
Fetal development of primate chemosensory corpuscles. I. Synaptic relationships in late gestation
Authors: Zahm Daniel S. , Munger Bryce L. 
Published: December 2004

AbstractFetal macaque chemosensory corpuscles during the last part of gestation contained chemosensory, sustentacular, and undifferentiated basal cells. Sustentacular cells had apical secretory granules and no specialized contacts with axons. Chemosensory cells contained basal collections of 80–100 nm dense core granules, and specialized axonal contacts of three types—afferent synapses, efferent synapses, and subsurface cisternae. Afferent synapses were commonly present on electron opaque cells with many 80–100‐nm granules, typical 40–60‐nm synaptic vesicles, and a few cisternae of smooth or granular endoplasmic reticulum. Cells with subsurface cisternae and/or efferent synapses were usually electron lucent, lacked vesicles and granules, and contained numerous intracytoplasmic cisternal elements. A continuum of intermediate forms was observed. It is postulated that transition of synaptic arrays accompanies the maturation of individual chemosensory cells.
The organization of two cutaneous submodalities in the forearm region of area 3b of cat somatosensory cortex
Authors: Sretavan David , Dykes Robert W. 
Published: December 2004

AbstractElectrophysiological data were collected from the forelimb region of somatosensory cortex in barbiturate‐anesthetized cats using low‐impedance microelectrodes in both perpendicular and nearly horizontal penetrations. The data within cytoarchitectonic area 3b were classified according to receptive field locus and submodality. The forearm cortex was shown to consist of segregated regions of slowly adapting and rapidly adapting neurons arranged in a pattern unique to each animal. The general organization of each submodality consisted of interdigitating bands of submodality‐specific neurons. Horizontal penetrations confirmed data obtained from vertical penetrations.The somatotopic representation within the forearm region was arranged in a way that was complementary to the submodality segregation. Each part of the forearm appeared to be represented by both the slowly adapting and rapidly adapting neurons so that area 3b contained two complete maps of the forearm. Yet, the slowly and rapidly adapting maps were organized so that the same body part was found in only one part of the cortex; the slowly and rapidly adapting regions, for each body part tended to be adjacent to one another. Area 1 was incompletely sampled; however, there appeared to be a separate representation of the cutaneous surface located there.
Electron microscopic studies of serially sectioned cat spinal α‐motoneurons: V. motoneurons innervating fast‐twitch (type FF) units of the gastrocnemius muscle
Authors: Kellerth J.‐O. , Conradi S. , Berthold C.‐H. 
Published: December 2004

AbstractTwo intracellularly stained gastrocnemius a‐motoneurons of the FF‐type (Burke et al., ′73) were studied ultrastructurally. The architecture and synaptology of the cell bodies and proximal dendrites were analyzed from long series of consecutive sections according to, a methgd previously described (Conradi et al., ′79a). Several of the dendrites had a base diameter exceeding 10 μm. The proportion of the cell surface area covered by boutons was 40‐50% for the soma and about 70% for the proximal dendrites. In both regions, about 20‐25% of the boutons were of the S‐type and 60‐70% of the F‐type. In general, the type FF α‐motoneurons exhibited the same gross synaptological characteristics as those found earlier in type FR α‐motoneurons (Kellerth et al., ′79), although the large boutons of the C‐type were more frequent on the proximal dendrites and axon hillocks of the present cells. M‐boutons of dorsal root origin were found on several of the proximal dendrites. The observed regional differences in the spectrum of boutons on the motoneuron surface seem to follow gradients operating in the somato‐fugal direction, and they are apparently independent of the size or direction of the neuronal processes.
Astrocytes in the nonmyelinated lamina cribrosa of the rat are less polarized than in the optic nerve proper: A freeze‐fracture study
Authors: Bäuerle Carin , Wolburg Hartwig 
Published: December 2004

AbstractAstrocytes in the lamina cribrosa of the adult rat optic nerve which is devoid of myelination were investigated by means of quantitative freeze‐fracturing. The orthogonal arrays of particles (OAPs) were found to be less concentrated in the membranes of subpial endfeet when compared to the OAP concentration in endfeet of the optic nerve proper. This result corresponds to that found previously in the myelin deficient rat (Rohlmann et al: Glia 5:259, 1992) suggesting that lack of myelination generally correlates with altered astrocytes. © 1993 Wiley‐Liss, Inc.
Differential intracellular compartmentalization of phosphotyrosine phosphatases in a glial cell line: TC‐PTP versus PTP‐1B
Authors: Faure Robert , Posner Barry I. 
Published: December 2004

AbstractIntracellular levels of protein‐phosphotyrosine are regulated by the protein‐tyrosine phosphatase (PTP) family. Cellular compartmentalization may play an important role in modulating the function of these enzymes. The recent demonstration that PTP‐1B is localized to the endoplasmic reticulum (Frangioni et al: Cell 68:545, 1992) is consistent with this proposition. In this study we have examined the intracellular distribution of TC‐PTP in a glial cell line (C6). Using indirect immunofluorescence we have shown that this enzyme is distributed differently from PTP‐1B and is mainly concentrated in the perinuclear region of these cells. © 1993 Wiley‐Liss, Inc.
Histamine and prostanoid receptors on glial cells
Authors: Inagaki Naoyuki , Wada Hiroshi 
Published: December 2004

AbstractGlial cells in vitro express at least two types (H1 and H2) of histamine receptors and three types (EP, FP, and TP) of prostanoid receptors. The receptors expressed by glial cells differ according to the cell type and source in the brain. Further‐more primary astrocytes of same type derived from the same brain region are composed of heterogeneous subpopulations expressing different subsets of receptors. Fura‐2 based Ca2+ microscopy revealed that astrocyte processes are important sites for histamine‐induced Ca2+ signalling. Histamine and prostanoid receptors on glial cells may play important roles in the actions of histamine and prostanoids in the central nervous system. © 1994 Wiley‐Liss, Inc.
Sarverogenin, vermutliche Struktur. Glykoside und Aglykone, 314. Mitteilung
Authors: Fuhrer H. , Zürcher R. F. , Reichstein T. 
Published: December 2004

AbstractSarverogenin is most probably a 3β, 11β, 14β‐trihydroxy‐7, 8β‐epoxy‐12‐oxo‐5β‐card‐(20:22)‐enolide (3). This follows from IR., NMR., and mass spectra together with former chemical results.
Der FISCHER'sche Indolringschluss mit 1, 3‐disubstituierten 4‐Piperidonen. 7. Mitteilung über synthetische Indolverbindungen [1]
Authors: Ebnöther A. , Niklaus P. , Süess R. 
Published: December 2004

AbstractTreatment of the arylhydrazones of 1, 3‐disubstituted 4‐piperidones with ethanolic hydrogen chloride (FISCHER reaction conditions) affords 1, 2, 3, 4‐tetrahydropyrimido [3, 4‐a]‐indoles in good yields. During catalytic hydrogenation in the presence of protons these tetrahydropyrimido‐indoles are split into 2‐(2‐methylamino‐ethyl)‐indoles. The formation of these tricyclic products can be explained by rearrangement immediately following the normal FISCHER reaction. If the substituent at the piperidine nitrogen is an acyl group, normal or rearranged products are formed, depending on the nature of the 3‐substituent.
Isolierung von (−)‐R‐4‐Hydroxy‐pyrrolidon‐(2) und einigen weiteren Verbindungen aus Amanita muscaria. 31. Mitteilung über Inhaltsstoffe von Fliegenpilzen
Authors: Matsumoto T. , Trueb W. , Gwinner R. , Eugster C. H. 
Published: December 2004

AbstractAus Carpophoren von Amanita muscaria (L.′ ex Fr.) HOOKER wurden neu β‐n‐Butyl‐D‐glucopyranosid, (−)‐R‐4‐Hydroxy‐pyrrolidon‐(2), Uracil, Hypoxanthin und (−)‐1,2,3,4‐Tetrahydro‐1‐methyl‐β‐carbolin‐3‐carbonsäure isoliert.
Beitrag zur Charakterisierung der Lipide aus den Linsen einiger Säugtiere
Authors: Bernhard Karl , Lesch Peter , Greub Hans‐Rudolf 
Published: December 2004

AbstractTotal lipids from the lenses of pigs, calves, cattle and fin whales have been separated into different fractions. Their lipid content seems to be the lowest of all organs. The predominant lipid classes are cholesterol, ethanolamine cephalines, and sphingomyelines. The analysis of the fatty acids after saponification showed differences in the main components depending on the source of the material. In all cases 5–7% hydrocarbons were found which are probably of alimentary origin and are deposited in the lens.
Induktive und sterische Effekte bei der BECKMANN‐CHAPMAN‐Umlagerung von Alkyl‐ketoxim‐pikryläthern
Authors: Fischer H. P. , Funk‐Kretschmar F. 
Published: December 2004

AbstractThe rates of the BECKMANN‐CHAPMAN rearrangement of the ketoximpicryl‐ethers 1a–1k in 1, 4‐dichlorobutane are correlated with parameters describing the bulk of the substituted groups R and R′. From regression analyses it is concluded that the relative rate constants are mainly controlled by steric contributions in the ground state, such as geminal interactions of R with R′ and vicinal interactions of R′ with OX, and less by inductive effects.Conformational equilibria between (Z)‐ and (E)‐isomers of N‐alkyl‐N‐picryl‐amids have been studied by NMR. in several solvents.
Partialsynthese von 4′‐Demethylepipodophyllotoxin. 22. Mitteilung über mitosehemmende Naturstoffe [1]
Authors: Kuhn M. , Keller‐Juslén C. , von Wartburg A. 
Published: December 2004

Abstract4′‐Demethylepipodophyllotoxin (III) has been synthesized by epimerisation of 4′‐demethylpodophyllotoxin (I) via the corresponding chloride II. An improved method for the preparation of III has been developed by selective ether cleavage of the easily available podophyllotoxin (V) using the bromoderivatives VI and VII as intermediates.
Viminolon, Strukturbeweis. Glykoside und Aglykone, 315. Mitteilung
Authors: Stöckel K. , Hürzeler H. , Reichstein T. 
Published: December 2004

AbstractReduction of di‐O‐benzoyl‐viminolon (1) with LiAlH4 gave a mixture of 17‐isopregn‐5‐ene‐heptols. Treatment of this mixture with NaIO4 produced the amorphous 12‐O‐formyl sarcostinketone (= 12‐O‐formyl‐3β, 8β, 12β, 14β‐tetrahydroxy androst‐5‐en‐20‐one) (4). This together with former results proves the structure of 1.
Über neue Bufadienolide aus Ch'an Su. Über Krötengifte, 34. Mitteilung
Authors: Höriger Niklaus , Linde Horst H. A. , Meyer Kuno 
Published: December 2004

AbstractTwo new bufadienolides, isolated from Ch'an Su, are proved to be 19‐oxo‐cinobufagin (III) and 19‐oxo‐cinobufotalin (V), respectively.
Über die absolute Konfiguration der Visnagane
Authors: Bernotat‐Wulf Hannelore , Niggli A. , Ulrich L. , Schmid H. 
Published: December 2004

Abstract(+)‐cis‐Khellactone methyl ether (4) and (−)‐trans‐khellactone methyl ether (6) had earlier been assigned the absolute configurations 3′‐S; 4′‐S and 3′‐S; 4′‐R, respectively, on the basis of the FREUDENBERG, rule. Both compounds together with their defunctionalised derivatives (−)‐7 and (+)‐8 (=(+)‐lomatin), obtained from a mixture of (+)‐visnadin (1) and (+)‐samidin (2), were investigated by the HOREAU method. A conformational analytical study showed that the optical yield should rise in the order 4 < 6 < 7, 8. This order was found and the α‐phenylbutyric acid liberated was always dextrorotatory. The centre 3′ of the khellactones and their derivatives must be R‐chiral and not S. Treatment of (−)‐6 with pyridinium perbromide gave (−)‐trans‐3‐bromokhellactone methyl ether (11) as orthorhombic crystals. The X‐ray crystal structure determination was made using the anomalous scattering of the Mo‐K α radiation by Br. The result, — centre 3′ R‐chiral (fig. g) — showed that the HOREAU method was correct.
Löslichkeiten und Aktivitätskoeffizienten von H2S in Elektrolytmischungen
Authors: Gamsjäger H. , Schindler P. 
Published: December 2004

AbstractFrom solubility measurements on hydrogen sulfide in aqueous solutions of the composition [H+] = HM, [Na+] = (I — H) M = A M, [Cl−] = I M at 25°C, the molar and molal activity coefficients of H2S have been calculated. The activity coefficients of H2S in the electrolyte mixtures have been found to be additive functions of the activity coefficients in the individual electrolyte solutions at the same ionic strength. This result is predicted by the internal pressure theory of salt effects on non‐electrolyte activity coefficients, provided that the volume change upon mixing two electrolyte solutions of the same ionic strength is zero.
Synthese von 1, 2‐Dimethyl‐phenanthro[1,2‐b]furan und 1‐Äthyl‐2‐methyl‐phenanthro[1,2‐b]furan. Furanabkömmlinge, 26. Mitteilung
Authors: Stöckel K. , Stöcklin W. , Reichstein T. 
Published: December 2004

AbstractWe describe here the synthesis of 1,2‐dimethyl‐phenanthro [1,2‐b] furan (11) and 1‐ethyl‐2‐methyl‐phenanthro [1,2‐b] furan (13). The starting material was the known ethyl 2‐methyl‐phenanthro [1,2‐b] furan‐1‐carboxylate (4). The two synthetized substances were characterized by their UV.‐, IR.‐, NMR.‐ and mass spectra, and identified with two products obtained by selenium dehydrogenation of anhydrohirundigenin.
Die Synthese der Alkaloide der Ergotoxin‐Gruppe. 70. Mitteilung über Mutterkornalkaloide [1]
Authors: Stadler P. A. , Guttmann St. , Hauth H. , Huguenin R. L. , Sandrin Ed. , Wersin G. , Willems H. , Hofmann A. 
Published: December 2004

AbstractThe syntheses of the alkaloids of the ergotoxine‐group i.e. ergocristine, α‐ and β‐ergokryptine, and ergocornine, are described. Using starting material with known stereochemistry these syntheses allowed to determine the absolute configurations also at C‐2′ and C‐12′ in the peptide part, which could not be derived from analytical data. All ergot alkaloids of the peptide type possess the same stereochemical structure.
Mikrobiologische Umwandlung von bicyclischen Monoterpenen durch Absidia orchidis (VUILL.) HAGEM. 2. Teil. Hydroxylierung von Fenchon und Isofenchon. 18. Mitteilung über Reaktionen mit Mikroorganismen [1]
Authors: Pfrunder B. , Tamm Ch. 
Published: December 2004

Abstract(+)‐Fenchone (3a) was transformed to 6‐exo‐hydroxy‐fenchone (6β‐hydroxy‐1, 3, 3‐trimethyl‐nor‐bornan‐2‐one) (1a) and to 5‐exo‐hydroxy‐fenchone 5β‐hydroxy‐1, 3, 3‐trimethyl‐nor‐bornan‐2‐one (4a) by the mycelium of Absidia orchidis (Vuill.) Hagem. The structure of the two products was proven by a detailed analysis of the NMR. spectra of the corresponding acetyl derivatives 2a and 5a respectively, and by CrO3‐oxidation. 1a yielded the β‐diketone 6a, and 4a the diketone 8a. Whereas 8a was stable to alkali 6a was cleaved to the cyclopentane carboxylic acids 7 and 9. — Incubation of (—)‐fenchone (3b) yielded the enantiomeric hydroxylation products 1b and 4b in the same ratio. ‐ (—)‐Isofenchone (11a) was transformed by Absidia orchidis into the two epimers 6‐endo‐hydroxy‐isofenchone (6β‐hydroxy‐1, 5, 5‐trimethyl‐nor‐bornan‐2‐one) (12a) and 6‐exo‐hydroxy‐isofenchone (6β‐hydroxy‐1, 5, 5‐trimethyl‐nor‐bornan‐2‐one) (10a.) CrO3‐oxidation of both 10a and 12a gave the same β‐diketone 6a. ‐ (+)‐Isofenchone gave the corresponding enantiomeric hydroxy derivatives 10b and 12b on incubation with Absidia orchidis.
Photoelektronspektroskopische Bestimmung der Wechselwirkung zwischen nicht‐konjugierten Doppelbindungen [1]. Vorläufige Mitteilung
Authors: Bischof P. , Hashmall J. A. , Heilbronner E. , Hornung V. 
Published: December 2004

AbstractThe interaction between the two non‐conjugated π‐bonds in 1, 4‐cyclohexadiene, norbornadiene and bicyclo[2.2.2]octadiene has been determined by photoelectron spectroscopy to be 1.0, 0.85 and 0.6 eV respectively.
Bemerkungen zum Metallmonoschichtmodell der Kationenadsorption
Authors: Schmidt E. 
Published: December 2004

AbstractDie Anwendung des thermodynamischen Formalismus ideal polarisierbarer Elektroden auf das Metallmonoschicht‐Adsorbat zeigt, dass der übliche, einer Nernst‐Gleichung analoge Ansatz für den Zusammenhang zwischen Potential und Oberflächenkonzentration bestimmte Ladungsstöchiometrie‐Eigenschaften des Adsorbats impliziert, und zwar verhält sich das adsorbierte Kation Me2+ so, als werde es beim Eintritt in die Interphase zur Neutralspezies Me0 entladen. Die Oberflächenladung ist dementsprechend eine lineare Funktion der Oberflächenkonzentration. Die Ladungssumme von diffuser Doppelschicht und allfälligen spezifischen Anionenadsorbaten ist eine reine Potentialfunktion.Das Metallmonoschichtkonzept ist ein Näherungsmodell eines Kationenadsorbats, dessen Realisierbarkeit in einfachen Fällen anhand austrittselektrischer Kriterien beurteilt werden kann.