Das kondensationsverhalten hydroxy- und chlormethylierter phenole und anisole mit dimethylphenolen

1973

Beitrag zur hydroxymethylierung von hydroxyphenylenmethylen-verbindungen sowie IR- und UV-spektroskopische untersuchungen dieser verbindungen

1973

Es wurden hohermolekulare α-Brom- bzw. α-Methyl-ω-hydroxy[(2-hydroxy-5-methyl-1,3-phenylen)methylene] nach LEDERER und MANASSE dargestellt; die hochste erreichte rel. mol. Masse betrug rund 700. Mit steigender rel. mol. Masse wuchsen Zahl und Anteil der Nebenprodukte, so das die Reinigung bis zur dunnschichtchromatographischen Reinheit immer verlustreicher wurde und die Ausbeuten auf 10–15% abfielen. Einige der Nebenprodukte wurden isoliert; ihre Konstitution wurde aufgeklart und durch IR- und UV-Messungen bestatigt. Tetrasubstitutionsbanden, Methylengruppen- und Hydroxylgruppenbanden der IR-Spektren wurden eingehend untersucht. Die HUNTERsche Beziehung wurde bestatigt und ihre allgemeinere…

Electron microscopic study on the larval and adult corpus allatum of Oncopeltus fasciatus dallas (insecta, heteroptera)

1973

1. The ultrastructure of the corpora allata of last larval instars and adults of Oncopeltus was studied. The unpaired gland undergoes submicroscopic alterations and shows signs of degradation in old animals. The organ is partly covered and penetrated by corpus cardiacum tissue. Axons with different types of neurosecretory granules form synaptoid contacts with the corpus allatum cells.

Metabolic aspects of the rhythmogenesis inAplysia pacemaker neurons

1973

Completely isolatedAplysia pacemaker neurons were used to investigate mechanisms of endogenous electrical rhythmicity. This preparation allows the study of pure pacemaker activity free from synaptic, ephaptic and/or humoral influences from the surrounding cells. The effect of some substances quite different in their mode of biochemical action were tested: sodium iodoacetate, phloridzin, dinitrophenol, heavy water, and ouabain. Each of these substances suppressed the spontaneous spike activity without any marked depolarizing or hyperpolarizing effect. Spontaneous spike activity of the neurons silenced after addition of one of these substances reappeared after addition of glucose. The restori…

Characterization of the binding of benzodiazepines to human serum albumin

1973

The binding of eleven benzodiazepine derivatives to human serum albumin (HSA) was determined by means of sephadex gel filtration. The albumin binding of the substances was characterized by the percentage of bound drug, the binding constants k +, K 1 and m, the number of binding sites per albumin molecule, and the free binding energy. Under the conditions chosen in these experiments there seems to exist only one binding site of the same type for all investigated benzodiazepines at the HSA molecule. The affinities of the benzodiazepines to this binding site are very different. It is discussed which part of the benzodiazepine molecule represents the main binding group.

false

1973

Über die Elementarreaktionen der radikalischen Polymerisation von Benzylmethacrylat

1973

Durch Kombination stationarer und instationarer Methodik (rotierender Sektor) werden die Absolutwerte der Geschwindigkeitskonstanten von Kettenwachstum und Kettenabbruch von Benzylmethacrylat unter dem Einflus verschieden viskoser Losungsmittel bestimmt. Die Radikalausbeute f hangt von der Viskositat des Losungssystems und der Art der Monomeren, dagegen nicht (oder fast nicht) von der Konzentration des Monomeren und der Geschwindigkeit der Radikalerzeugung ab. Daraus wird geschlossen, das ein merklicher Anteil von Zwillingsrekombinationen auserhalb des primaren Losungsmittelkafigs stattfindet. Die Geschwindigkeitskonstante kw des Kettenwachstums stimmt praktisch uberein mit der des Methylme…

Die O2-Druckverteilung in Rinde und Mark der Rattenniere unter Normoxie und Hyperoxie

1973

Unter standardisierten Bedingungen werdenin vivo die O2-Drucke unter Normoxie (FIO2=0,21) und Hyperoxie (FIO2=1,0) in Rinde und Mark der Rattenniere polarographisch mit Goldmikroelektroden (Spitzendurchmesser 3–8 µm) gemessen. Bei kontinuierlichem Vorschub der Elektrode wird diepo2-Verteilung in Rinde und Mark ermittelt,po2-Histogramme aufgestellt und die mittleren Gewebs-po2-Werte errechnet. In Kontrolluntersuchungen erfolgte die Messung der Durchblutung, der Blutgasdaten und der O2-Aufnahme der Niere bei Luft- und O2-Atmung.

Über Chalkogenolate, LXVI. Untersuchungen an cis ‐1,2‐Dicyanäthylen‐1,2‐dithiolaten 4. Kristallstruktur von Bis(methylthio)maleonitril

1973

Die Struktur des Bis(methylthio)maleonitrils (1) wurde rontgenographisch aus Diffraktometer-Einkristalldaten bestimmt und bis zu einem konventionellen R von 0.049 verfeinert. Der (NCCS)2-Teil unterscheidet sich in seinen Dimensionen nicht vom (NCCS)22 -Liganden in Ubergangsmetallkomplexen Die grosere Stabilitat von 1 gegenuber dem Fumarsaure-Isomeren wird diskutiert. Die Struktur besteht aus planaren 1-Schichten parallel zur Flache (101) mit optimaler Packungsdichte der 16-fach koordinierten Molekule. On Chalcogenolates, LXVI. Studies on cis-1,2-Dicyanoethylene-1,2-dithiolates The crystal structure of bis(methylthio)maleonitrile (1) has been determined from single crystal X-ray data and ref…

Amino acids requirements of measles virus in HeLa cells.

1973

A low plating efficiency for measles virus was obtained when arginine, threonine and isoleucine were omitted from Eagle's basal medium and a stimulatory effect on the plaque production was produced by increasing the concentration up to 0.5 mm of arginine and glutamine. However, of all amino acids in Eagle's basal medium, only methionine was found to be essential for the synthesis of infectious progeny virus. Omission of any one of the other amino acids from the culture medium permitted limited virus production, but none whatever could be detected in the absence of mediummethionine. Moreover, when methionine was restored to infected cultures after 24 hours of deprivation, release of virus be…

An extension of the algebra of sets

1973

We shall explain the aim which leads us in the construction of an extended system of the algebra of sets1. The symbol 1. {*:?(*)} denoting the set of these and only these elements of domain of the variable x which satisfy the propositional condition (propositional function or form) ?9 (x)" is in com? mon use nowadays, so that it is adopted in school courses of mathematics in many countries, and in Poland as well. This condition will be said to define the set 1. However, if we admit propositional conditions which are meaningless for some values of their variables then we encounter some difficulties connected with the ex? pression 1. The formulae 2. {x : 9 (*)} = {x : 9 (*)}' 3. {x : 9 (s) v …

Investigation of Gamma Rays from the36S(p,γ)37Cl Reaction

1973

The excitation curve of the 36S(p,γ)37Cl reaction has been measured in the proton energy range 1 000-1 900 keV. 109 resonances were observed. The decay schemes for 13 resonances and energies and branching ratios of 15 bound states have been obtained by means of Ge(Li) detectors. Seven of the bound states have not been reported earlier. Lifetimes or lifetime limits of 5 bound states have been measured by means of Doppler-shift attenuation method.

Complexes of organometallic compounds XXXIII. The coordination chemistry of dimethyl and diphenylthallium(III) ith tridentate ligands

1973

Summary Several novel complexes Na[Me 2 TIL] and Na[Ph 2 TIL] (L 2− =dianion tridentate ligands with S, N, and O donor atoms) were synthesized, and investigated by infrared spectroscopy in the solid state, and by electronic and PMR spectroscopy in solution. Suggestions for the configuration of the complex anions are advanced and the nature of species present in solution is discussed.

MOTILITY OF MYCOPLASMAS

1973

Ultimate load analysis of plate foundations

1973

The behaviour of circular plates used as isolated foundations is investigated on the basis of earlier studies[6], [7] of the limit state of indefinite plates resting on elastoplastic continua and subjected to distributed loads. The upshot is an easy-to-use procedure of ultimate load analysis that permits the determination of: --the limit load for simultaneous collapse of plate and continuum --and the limit load for collapse of the continuum only according to the different behaviour of the two elements constituting the system.

Effects of photodynamic processes and ultraviolet light on duck and hen egg-white lysozymes.

1973

— The photochemical yields for inactivation and amino acid destruction in hen and duck egg-white lysozyme are presented. Duck lysozyme II is devoid of histidine but it has two more tyrosine residues than does hen lysozyme. The data indicate that sensitized oxidation of the single histidine residue of hen lysozyme is of no significance for the inactivation of this lysozyme. The ultraviolet destruction of tryptophan and cystine residues appears to be equally related with the loss in enzymatic activity of hen lysozyme. In the case of duck lysozyme, however, the ultraviolet inactivation appears to be predominantly governed by the destruction of cystine residues.

Erratum to: A semi-classical derivation of the spin-orbit electromagnetic interaction

1973

Phonon Bandwidth and Rate Equations in Avalanche Relaxation

1973

Complementation among developmental mutants in Aspergillus nidulans.

1973

In heterokaryons between pairs of aconidial mutants of Aspergillus nidulans one of the component strains usually shows a striking prevalance in the contribution to the conidial crop. By assuming that the prevailing strain is blocked earlier and the succumbent one later in the process of differentiation, a series of mutations can be arranged in a consistent order. Some mutant strains do not fit the scheme exactly but show a general tendency to be succumbent to “early” mutants and prevalent over the “late” ones. A criterion for arraying genes involved in differentiation according to the order of their physiological action is proposed.

Die kationische ε-caprolactam-polymerisation, 6. Amidin-endgruppen bei der mit caprolactam-hydrochlorid initiierten caprolactam-polymerisation

1973

Kinetik und Molekulargewichtsverteilung eines anionischen Polymerisationsprozesses mit momentanem Start bei simultanem Monomerabbruch

1973

Die Kinetik und die Molekulargewichtsverteilung wird fur einen anionischen Polymerisationsprozes mit einem momentanen Startschritt und mit simultanem Monomerabbruch berechnet. Ein derartiger Polymerisationsablauf ist bei der anionischen Polymerisation von Methylmethacrylat in polaren Losungsmitteln zu erwarten. — Die Molekulargewichtsverteilung geht mit steigendem Monomerabbruch in eine SCHULZ-FLORY-Verteilung uber. The kinetics and the molecular weight distribution are calculated for an anionic polymerization with rapid initiation and simultaneous deactivation by the monomer. Such a process is to be expected for the anionic polymerization of methylmethacrylate in polar solvents. — The mole…

Zur kinetik der anionischen polymerisation von methyl-methyacrylat in tetrahydrofuran bei −75°C

1973

Die anionische Polymerisation von Methylmethacrylat (MMA) in Tetrahydrofuran (THF) verlauft bei −75°C mit Cumylcasium bzw. oligomerem α-Methylstyrylcasium als Initiatoren ohne erkennbare Nebenreaktionen analog der anionischen Polymerisation von unpolaren Monomeren in atherischen Losungsmitteln. Als Beweis wird hauptsachlich die enge Molekulargewichtsverteilung der unter diesen Bedingungen hergestellten Polymethylmethacrylate angefuhrt. Bei −75°C betragen die Geschwindigkeitskonstanten fur die Monomeranlagerung an das Ionenpaar kw(±) = 80 dm3 mol−1 s−1 und an das freie Anion etwa kw(−) ≈ 6 · 104 dm3 mol−1 s−1. Leitfahigkeitsmessungen ergeben, das die Dissoziationskonstante des Polymethylmeth…

Pharmakologisch aktive polymere, 5. Modellreaktionen zur umsetzung von pharmaka und enzymen mit monomeren und polymeren reaktiven estern

1973

Die Darstellung reaktiver Ester der Acryl-, Methacryl- und N-Vinylcarbaminsaure wird beschrieben. Die Verbindungen sind im Gegensatz zu anderen reaktiven Saurederivaten wie Saurechloriden, -anhydriden und Isocyanaten kristalline Monomere, die gut zu handhaben sind. Sie lassen sich leicht zu unvernetzten, loslichen Polymeren homo- und copolymerisieren. Die Copolymerisationsparameter wurden bestimmt. Entsprechend wie die aus der Peptidchemie bekannten reaktiven Ester reagieren sie in monomerer wie in polymerer Form bei niedriger Temperatur selektiv und schonend mit Nucleophilen in guten Ausbeuten, z. B. mit Aminen in wasriger Losung. Dies eroffnet die Moglichkeit zur nebenreaktionsfreien Bind…

Über eine Beziehung zwischen Verdünnunasentropie und Verdünnungsenthalpie in Lösungen von Polystyrol und Polymethylmethacrylat

1973

Durch Lichtstreuungsmessungen wurde der Entropieanteil und der Enthalpieanteil des 2. osmotischen Virialkoeffizienten (A2) von athermischen und exothermischen Losungen von Polystyrol (PS) und Polymethylmethacrylat (PMMA) bei 25°C und Normaldruck bestimmt. Zur Auffindung von athermischen und exothermischen Losungsmitteln fur diese Polymeren wurde die Temperaturabhangigkeit des STAUDINGERindex verwendet. Die ermittelten thermodynamischen Grosen A2, A2,S und A2,H ergeben zusammen mit fruheren Messungen eine beziehung, die nahezu unabhangig vom speziellen System ist. The second osmotic virial coefficient A2 and its entropic and enthalpic parts of athermal and exothermal solutions of polystyrene…

SU(4) breaking, allowed transitions and total muon capture rates in nuclei

1973

The authors study muon capture rates in light nuclei and show that one can evaluate them in a model-independent way by correcting the Primakoff closure approximation to the first order in the neutrino energy dependence. In this framework the interplay between the existence of allowed transitions and SU(4) breaking is analyzed. In the correction to the first order in the neutrino energy dependence by a sum rule, Majorana and SU(4) breaking potentials are taken into account. The method is also applied to single multipolar transitions, in particular for the dipole transitions. General considerations are illustrated for /sup 6/Li and /sup 12/C by explicit calculations. The stability of the resu…

Zur Kanzerogenit�t des Koprosterins, eines intestinalen Reduktionsprodukts des Cholesterins

1973

A selective microscale x-ray fluorescence analyzing method for determination of trace elements

1973

Abstract A new selective X-ray fluorescence analyzing method for trace element determination has been developed. In this method each trace element is measured independently. The excitation source is an X-ray tube that has a changeable anode and a variable high voltage. The exciting radiation is shaped with critical absorbers. The sample is viewed at backward angles through an absorber to reduce backscattered radiation. The estimated accuracy of this method is of the order of 10 per cent in thesub-ppm range of trace element concentration in organic samples. Measurement times are of the order of a few minutes.

Small angle X-ray scattering from amorphous polymers arising from heterogeneities

1973

The small angle X-ray scattering of glassy polymers (PET, PC, PVC, PMMA) and of polymer melts (PE) was studied. The dependence of the intensity scattered at small angles on the sample treatment suggests that neither the inherent structure of the pure polymer phase nor microholes are the origin of the scattering. In agreement with all experimental facts the scattering can be attributed to foreign particles such as for instance stabilizers in the polymer matrix. The consequence of this result is discussed with respect to the nodular structure of the amorphous phase and with respect to structural models of the amorphous phase. The nodular structure is not related to regions of different densit…

DETERMINATION OF NUCLEAR GROUND STATE PROPERTIES FAR FROM STABILITY BY OPTICAL PUMPING

1973

The possibilities of determining nuclear spin, moments and variation in charge volume by optical pumping of on line masseparated isotopes are described for the example of the isotopic chain lY1Hg-205Hg. The variation in nuclear charge volume (6 ) along this chain and in particular its abrupt change for the lightest Hg-isotopes, indicating a phase transition in nuclear structure, are discussed. 1. Introduction. - This talk is based on expe- riments (I), (2), (3) performed recently by a visiting team (*) at the ISOLDE facility at CERN with the members : J. Bonn, G. Huber, H.-J. Kluge, U. Kopf, L. Kugler, J. Rodriguez, and E. W. Otten. The investigation of the hyperfine structure (hfs) and iso…

Moulting hormone content in prothoracic glands and oenocytes ofTenebrio molitor within a moulting cycle

1973

An isolierten und homogenisierten Prothorakaldrusen und Oenocyten vonTenebrio wurde der Gehalt an Hautungshormonen mit Hilfe des Calliphoratests bestimmt. Dabei stellte sich heraus, dass sowohl Prothorakaldrusen als auch Oenocyten wahrend des gesamten Hautungszyklus verpuppungsaktive Stoffe, wenn auch in unterschiedlicher Menge, enthalten. Die Ergebnisse werden mit jenen verglichen, bei denen der Hormontiter durch Extraktion ganzer Tiere bestimmt wurde. In Verbindung damit wurde das Zusammenspiel von Synthese und Abbau der Hormone diskutiert.

On gamma-ray emission from CYG X-2

1973

We discuss the importance of hard X- and gamma-ray emission from thermal X-ray sources to obtain a more realistic picture of these objects.

Design, construction and performance of the energy compressing system of the Mainz 300 MeV electron linac

1973

Abstract For the sake of better energy resolution of the 300 MeV electron linac of Mainz university a system has been built which transforms a sharply bunched beam of poor energy resolution into a beam of sharply defined energy, while its bunches are smeared out. The system is described, its design philosophy and some essential construction details are given. The operating experience of the last 6 months since completion of the system is communicated.

Untersuchungen zum Mechanismus der blutdrucksteigernden Wirkung von Mineralokortikoiden

1973

1. Es wird uber Untersuchungen zu der Frage berichtet, ob die blutdrucksteigernde Wirkung von Mineralokortikoiden mit einer Anderung der Noradrenalininaktivierung in Zusammenhang steht.

Stimulatory effects of DB-c-AMP and adrenaline on myocardial contraction and 45Ca exchange. Experiments at reduced calcium concentration and low freq…

1973

The effects of adrenaline (2.2×10−6 M) and cyclic N6-2′-O-dibutyryl-adenosine-3′,5′-monophosphate (DB-c-AMP; 10−3 M) on mechanical performance, 45Ca uptake and total tissue calcium concentration were investigated in electrically stimulated left auricles isolated from female rats weighing 180–220 g. The experiments were performed at reduced [Ca]e of 0.45 mM and at various frequencies of stimulation (0–120 beats/min). In the first series of experiments 45Ca incubation time was 5 min. Under these conditions DB-c-AMP as well as adrenaline enhanced contractile force to 300–450% of the control values at all frequencies tested (Fig.1). This increase in contractile force was accompanied by a signif…

Adrenaline, DB-c-AMP and myocardial 45Ca exchange. Comparative studies in rat and guinea-pig auricles

1973

The positive inotropic effect of adrenaline has been assumed to result from an increase in the intracellular level of c-AMP which, in turn, might enhance the permeability of the cardiac cell membrane to Ca2+. In order to further test this hypothesis, the effects of cyclic N6-2′-O-dibutyryl-adenosine-3′,5′-monophosphate (DB-c-AMP; 10−3 M) on mechanical performance, 45Ca uptake and total tissue calcium concentration were investigated in electrically stimulated (120 beats/min) left auricles isolated from female rats weighing 180–220 g. The experiments were performed in Tyrode solution containing 0.9 mM CaCl2; the duration of 45Ca exposure was 3–60 min. In this study, DB-c-AMP markedly enhanced…

Interrelationship between demethylation of p-nitroanisole and conjugation of p-nitrophenol in rat liver

1973

The metabolism of p-nitroanisole (pNA) and p-nitrophenol (pNP) was studied in isolated rat livers perfused with a hemoglobin-free medium. The activity and viability of the surviving organ was tested by recording pH, “arterial” and “venous” oxygen tension as well as the disappearance of added pNP. pNA is converted to its primary metabolite pNP which, in turn, is excreted into the perfusion medium as conjugates. The coordination of pNA oxidation and the conjugation reactions of pNP were investigated. When 50 μM pNA is added as substrate 0.4±0.1 nmoles×ml−1×(g liver)−1 are excreted as pNP-glucuronide and 3.5±0.2 nmoles×ml−1×(g liver)−1 as the sulphate within 90 min. When pNP itself (50 μM) is …