Zur feinstrukturellen Anpassung des Transportepithels am Ventraltubus von Collembolen bei unterschiedlicher SalinitÄt

1977

Das Transportepithel am Ventraltubus verschiedener Collembolen-Arten —Podura aquatica, Lepidocyrtus ruber, Sminthurides aquaticus undTomocerus vulgaris — wurde auf salinitAtsabhAngige VerAnderungen der Feinstruktur hin untersucht. Als Beispiel langfristiger Adaptation wurdePodura aquatica aus zwei Populationen von Salzlaken des Neusiedlersee-Gebietes mitLepidocyrtus ruber aus dem Supralitoral der Mittelmeerkuste der Insel Elba/Italien verglichen. Die Tiere von stark salzhaltigem Substrat zeigten eine Ruckbildung der fur Transportepithelien typischen Strukturen, in erster Linie eine Reduzierung des apikalen Faltensaumes und der Mitochondriendichte. Auf einer Salzlake geringerer SalinitAt erg…

Gelchromatographie, Versuche zur Strömungsdispersion mit radioaktivem Polystyrol

1977

Experimente mit Mischungen aus mit 14C radioaktiv markiertem, monodispersem Polystyrol mit inaktivem Polystyrol zeigen, das bei der gelchromatographischen Trennung ein molekularuneinheitliches Polymeres sich wie die Summe aus molekulareinheitlichen Proben verhalt. Experiments with mixtures of 14C-labelled monodisperse polystyrene and inactive polystyrene show, that in gel chromatography a molecularly nonuniform polymer acts like the sum from molecularly uniform samples.

false

1977

Copolymers from styrene and 1-vinylimidazoles (4a–f), form low spin adducts with iron(II) porphyrins and iron(III) porphyrins, when the content of imidazolyl groups in the polymer is ten mole percent or more. With polymers having a content of imidazolyl groups of less then one mole percent, only high spin adducts are observed. With terpolymers, in which the porphyrin is covalently bound to the copolymer the same phenomenon is observed. Only the high spin Fe(II) porphyrin adducts in the solid state adsorb molecular oxygen like cobalt(II) porphyrins under the same conditions. Adsorptions and desorptions of oxygen are much slower in the cases of iron(II) porphyrins than with the cobalt(II) por…

Die Invarianz gewisser von Thetareihen erzeugter Vektorr�ume unter Heckeoperatoren

1977

Increasing the elastic modulus of polyamides

1977

On ternary rings of derivable planes

1977

Numerically stable computation of step-sizes for descent methods. The nonconvex case

1977

The computation of step-sizes which guarantee convergence in unconstrained minimization by descent methods is considered. The use of a “control” or “range” function is highly attractive for this purpose because of its simplicity. Since the Armijo-Goldstein test may fail prematurely due to numerical instability near the minimizer, we consider a range function based on gradient values alone as has been done forg convex in [8]. Numerical algorithms are given for the computation of step-sizes whose behaviour under roundoff is shown to be benign in the sense of F. L. Bauer [5].

Macroamylasaemia after treatment with hydroxyethyl starch

1977

After infusion of 500 ml of 6% hydroxyethyl starch into fifty-four patients an increase of serum amylase was observed which in fifty-one cases exceeded the upper limit of normal (190 U/l). In most cases serum amylase reached twice the basal value. Renal function influenced the duration of the increase in serum amylase, but not the maximum increase (201+/-15 U/l; mean+/-SEM). In patients with advanced renal failure (glomerular filtration rate (GFR) = 2-10 ml/min) serum amylase was still markedly elevated after 72 h (298+/-24 U/l; mean+/-SEM). In patients with normal renal function (GFR greater than 90 ml/min) serum amylase decreased to 183+/-40 U/l (mean+/-SEM) within 72 h without reaching b…

Alterations of Activities of Ribonucleases and Polyadenylate Polymerase in Synchronized Mouse L Cells

1977

The activities of the three known catabolic and the one anabolic polyadenylate enzymes have been determined in synchronized L5178y cells: endoribonuclease, exoribonuclease, 5'-nucleotidase and poly(A) polymerase (Mg2+-dependent). These four enzymes were found primarily in the nuclear fraction. The activity of poly(A) polymerase remains essentially constant during the transition from G1 to S phase. However, the poly(A) catabolic enzyme activities increase parallel with DNA synthesis; the endoribonuclease activity increases 4-fold during G1 to S phase, the exoribonuclease and the nucleotidase activities increasing 30-fold and 16-fold. During the S phase the poly(A)-degrading enzymes are far m…

Polymerization of mono- and multilayer forming diacetylenes

1977

Heptadeca-2,4-diine-1-ol and Heptadeca-2,4-diine-1-acid were synthesized and their polymerization behaviour in the solid state was investigated. Both compounds polymerize thermally below the melting point and photochemically under the action of uv-light to form polymers via 1,4-addition to the conjugated triple bonds with a backbone of conjugated double-and triple-bonds. The photoresponse spectra resemble the absorption spectra exhibiting maxima of photoreactivity in the absorption band of the conjugated triple bonds of the monomers.

Untersuchungen zur Höhe und Bedeutung des intramedullären Druckes während des Einzementierens von Hüftendoprothesen

1977

Im Hinblick auf die bekannten intraoperativen Komplikationen bei der Implantation von Huftendoprothesen mit Knochenzement und auf die moglichen Auswirkungen auf die Prothesenverankerung werden experimentelle Untersuchungen an frischen Leichenknochen uber die wahrend der verschiedenen Phasen der Implantation auftretenden intramedullaren Drucke im Femur ohne und mit verschiedenen Moglichkeiten der Markraumentlastung durchgefuhrt. Wahrend bei unentlasteten Markraumen Drucke bis uber 5 kp/cm2 entstehen, vermag eine geeignete Entlastung die Druckentwicklung weitgehend zu reduzieren. Dadurch wird neben der Verhutung der Fettembolie gleichzeitig die Verankerung des Zementlagers im Knochen entschei…

Über die möglichkeiten zur bestimmung von mischungsenthalpien und -volumina aus der molekulargewichtsabhängigkeit der kritischen entmischungstemperat…

1977

Cloud-point curves and critical curves (Tc = f(p)) have been measured for the system trans-decahydronaphthalene/polystyrene and three different molecular weights of the polystyrene component (2,5 · 106; 3,9 · 105; 1,1 · 105). It turned out that by variation of the pressure the metastable region can be investigated up to the spinodal curve. A comparison of the theta-temperatures and the enthalpy contributions χH (to the Flory-Huggins interaction parameter χ) resulting from the measured critical temperatures according to Shultz-Flory, with the corresponding directly obtained literature data, demonstrates that, although the extrapolation of Tc to infinite molecular weight is feasible, χH obtai…

Herstellung, charakterisierung und lösungseigenschaften von einheitlichen styrol-α-methylstyrol block-copolymeren

1977

An improved anionic polymerization technique for the preparation of highly uniform styrene/α-methylstyrene linear two-block copolymers is described. Three sets of samples with molecular weights M were prepared under equal experimental conditions, namely polystyrenes (2 · 105 < M < 3 · 106), poly(α-methylstyrene)s (7 · 104 < M < 4 · 106), and block copolymers (2 · 105 < M < 2,5 · 106). Ultracentrifugation in a density-gradient does not show any chemical heterogeneities in the block copolymers. The molecular polydispersity U = Mw/Mn–1 is U = 0,03 or less as estimated from GPC-measurements. The high molecular and chemical homogeneity of the block copolymers and the optical similarity of the tw…

Die Komplexchemie niederer Schwefeloxide, IV ESCA-Untersuchungen an S2-, S2O- und S202 -Komplexen des Iridiums / The Complex Chemistry of Low Sulfuro…

1977

The ESCA spectra of the complexes [(TPE)2Ir(S2)]Cl, [(TPE)2Ir(S2O)]PF6 and [(TPE)2Ir(S2O2)]Cl, (TPE = Ph2P(CH2)2PPh2, “diphos”), have been investigated. The binding energy data for the S 2p, Ir 4f and P 2p electrons were measured and are discussed.

Biomechanische Untersuchungen über das physikalische Verhalten von Kapselgewebe und Neokapselgewebe des menschlichen Hüftgelenkes

1977

Untersucht wurden je 10 Kapselproben bei Erstbzw. Zweiteingriffen am menschlichen Huftgelenk. Aus jeder exzidierten Kapsel konnten 2 Probekorper hergestellt werden. Die Untersuchungen uber die mechanischen Eigenschaften der Huftgelenkkapsel und der Huftgelenkneokapsel ergaben beinahe gleiche physikalische Kenngrosen. Die sog. Neokapsel hat sich demnach in erstaunlicher Weise den Belastungen angepast. Lediglich die Zugfestigkeit ist bei der Neokapsel deutlich hoher. Die etwa doppelt so grose maximale Spannung ist durch die starke narbenartige Vermehrung der kollagenen Anteile erklarbar. Entsprechend der Gelenkfunktion mus die Kapsel in verschiedenen Richtungen entfaltbar sein. Insgesamt wird…

What can be learnt about nuclear polarization from a consistency analysis ofe ? cross sections and muonic X-rays for208Pb and the isotone pair209Bi/2…

1977

A joint analysis of recent electron scattering cross sections and muonic atom X-ray energies is performed for208Pb and the isotone pair209Bi/208Pb. From the compatibility of the experimental data one can learn about the nuclear polarisation correction. However, we find this information not to be as accurate as other authors claimed when we take into consideration the ambiguities in the treatment of the corrections of the higher levels.

Improvements in the diagnosis and surgical management of lesions in and around the orbit

1977

Local skin necroses after intramuscular injection -Experimental animal studies-.

1977

The pathogenesis of local skin necroses after intramuscular injection of various drugs such as phenylbutazone (Embolia cutis medicamentosa, Nicolau's syndrome) is not clear. In an attempt to simulate this clinical feature experiments were performed on the rabbit ear lobe. A 20% phenylbutazone solution was injected paraarterial, intraarterial and paraarterial after perforation of the vessel. The drug produced a violent inflammation with all kinds of application. The local inflammation induced by paraarterial injection resulted in a fine scarring. Both other kinds of application produced necroses or even perforations. The histological examinations in these cases revealed massive destructions …

Strukturuntersuchungen von polyamiden aus cyclischen dicarbonsäuren und piperazin durch direkten abbau im massenspektrometer

1977

Polyamide aus 1,2-Cyclobutan-, 1,2-Cyclopentan- und 1,2-Cyclohexandicarbonsaure und Piperazin wurden direkt in der Ionenquelle eines Massenspektrometers pyrolysiert. Die hohe Empfindlichkeit der massenspektrometrischen Methode erlaubt, bei Abbauraten von ca. 1%/min zu pyrolysieren und dadurch selektive thermische Abbaumechanismen neben den Fragmentierungsreaktionen nachzuweisen. Durch thermischen Abbau werden dabei Oligomere mit Piperazinendgruppen sowie gesattigte und ungesattigte Cyclobutan-, -pentan- und -hexanendgruppen gebildet. Polyamides of 1,2-cyclobutane-, 1,2-cyclopentane- and 1,2-cyclohexane-dicarboxylic acid and piperazine were pyrolyzed directly in the ion source of a mass spec…

Aneurysms of the coronary arteries in infants and children. A review, and report of six cases.

1977

In recent years large numbers of the so-called “mucocutaneous lymph node syndrome” or “Kawasaki's disease” have been described by Japanese workers, but instances of this disorder are only now being reported as isolated cases by European or North American physicians. The disease has, therefore, been considered to be a new entity. One of its most striking features is the development of aneurysms of the coronary arteries in infants or children, which may lead to sudden death. Aneurysms of the coronary arteries in childhood are rare, and hence it was considered relevant to report six such cases, and to examine their possible relationship to Kawasaki's disease. The pathological changes underlyin…

Does cyclic GMP mediate the negative inotropic effect of acetylcholine in the heart?

1977

DURING vagal stimulation the pacemaker activity of the heart is diminished. The reduction in heart rate is due to a release of acetylcholine (ACh) from the parasympathetic nerve terminals that increases the permeability of the myocardial cell membrane for potassium ions (for review see ref. 1). This is accompanied by a shortening of the action potential duration in atrial muscle and a diminished calcium uptake2, which in turn results in a negative inotropic effect. Voltage clamp experiments in mammalian atrial muscle have shown that with higher concentrations of ACh not only is the potassium current augmented but also the slow inward current of calcium is reduced3. It is not clear how the c…

Die intestinale Resorption von Digoxin bei Patienten mit progressiver Sklerodermie

1977

Bei 18 Patienten mit progressiver Sklerodermie wurden Untersuchungen zur enteralen Resorption von Digoxin durchgefuhrt. Dazu erhielten 8 Patienten im Cross-over-Versuch eine einmalige intravenose und orale Gabe von 0,5 mg Digoxin. Beim Vergleich der Flachen unter der Plasmakonzentrations-Zeitkurve uber 8 Stunden fand sich bei 4 Patienten eine verminderte Digoxin-Resorption von weniger als 55% der Dosis. Bei allen 8 Patienten ergab sich eine statistisch signifikante positive Korrelation zwischen der D-Xylose- und der Digoxin-Resorption. Bei 12 Patienten wurden wahrend der Dauertherapie die Digoxinplasmaspiegel und die 24 h-Urinausscheidung des Glykosids an 3 aufeinanderfolgenden Tagen ermitt…

false

1977

Deuteron relaxation times T1 of polystyrenes deuterated at the backbone (PS-d3) and the phenyl ring (PS-d5), respectively, have been measured in solutions of benzene and diethyl malonate as a function of concentration and temperature. We conclude that the motion of the phenyl ring is faster than that of the backbone, the difference being smallest at high temperatures around 180°C. The temperatures dependence is discussed in relation to the activation energies in polystyrene.

Synthesis of polycyclic fused benzimidazole derivatives

1977

Am easy method for the synthesis of tetraeyclie systems containing an imidazole and an iso-thiazole or an imidazole and a thiazine ring, by reacting 2H-1,3-benzothiazine-2-thion-4(3H)one with aromatic primary diarnines is reported. The structures were assigned based upon mass spectra and modes of cleavage of the compounds. The most important fragments are described.

La région en analyse spatiale

1977

Traiter d'aménagement et de développement régional et interrégional renvoie à la question de savoir comment définir la région. Malheureusement, l'analyse spatiale n'apporte pas une solution claire à ce problème. Le mot "région" lui-même est si vague qu'il est utilisé concurremment avec d'autres, tout aussi vagues, tels que zone, aire, province, district, domaine, voire espace. La région, comme concept, soulève a fortiori de redoutables difficultés. A la limite, dans certains travaux d'économie régionale ou urbaine,ce concept est vidé de tout contenu spatial. La région ou la ville n'ont ni dimension, ni forme. Elles sont assimilées à des points. Ce type d'études est,il faut le souligner, étr…

e System and intrahepatocelullar HBcAG and HBsAG in HBsAG positive patients with liver diseases and healthy carriers.

1977

Patients with hepatitis-B surface antigen positive liver diseases and healthy carriers were studied for the presence of e-antigen and anti-e as well as for intrahepatocellular HBsAG and hepatitis-B core antigen. The e-antigen was demonstrated in 9 out of 12 patients with chronic perisitent hepatitis, in 15 out of 39 patients with chronic active hepatitis, in 3 out of 40 patients with acute type B hepatitis, and in 2 out of 9 patients with a protracted course of type B hepatitis. No e-antigen was found in healthy HBsAG carriers nor in patients with complete recovery from type B hepatitis one year after onset of the disease. Anti-e was detected in 24 out of 61 healthy HBsAG carriers with a no…

Non linear viscoelasticity of polymeric liquids interpreted by means of a stress dependence of free volume

1977

Several existing data of non-linear viscoelasticity of amorphous polymers aboveT g are here interpreted by assuming that the free volume changes during the motion. Equations of a stress-temperature equivalence are suggested which favorably compare with the data. It is also shown that the volume variations are sufficiently small to have escaped observation.

Gaschromatographisch-massenspektrometrische identifizierung der durch umsetzung von aminen mit isocyanaten gebildeten harnstoffderivate

1977

Abstract Gas chromatographic-mass spectrometric identification of urea derivatives formed by the reaction of amines with isocyanates N,N′-Di- and N,N′,N′-trisubstituted ureas constitute suitable derivatives for the gas chromatographic (GC) determination of primary and secondary amines. The GC identification of N- tert. -butyl-,N′,N′-alkyl urea derivatives presented in the first communication has been succesfully confirmed by mass spectrometry (MS) and mass fragmentometry. The reproduced mass spectra of six N- tert. -butyl-,N′,N′-alkyl ureas were interpreted according to the decomposition mechanisms of less complicated alkyl ureas known from the literature. Using combined GC-MS the detection…

NonleptonicKdecay rate in terms of spectral-function integrals: A short-distance approach

1977

In unified gauge theories of the weak and electromagnetic interactions it is shown that the matrix element for the decay ${K}_{S}^{0}\ensuremath{\rightarrow}2\ensuremath{\pi}$ can reliably be expressed in terms of integrals over spectral functions if (i) modified spectral-function sum rules of the Das, Mathur, and Okubo type are valid, or if (ii) the strong interactions are asymptotically free and the Glashow-Iliopoulos-Maiani mechanism holds. In these cases the contributions of the low-lying pseudoscalar and vector mesons to the spectral-function integrals suffice to account for the decay rate.

Myogenesis and contraction in the early embryonic heart of the rainbow trout

1977

Myogenesis in the embryonic heart of the rainbow trout, Salmo galrdneri (Rich.), was investigated electron microscopically from the 29th to the 41st somite stage. Thick and thin myofilaments are formed simultaneously as well as precursors of Z-lines, to which the thin filaments are attached. The genesis of filaments takes place in the region around the intracellular yolk droplets. The first myofibrils appear by the 33rd somite stage, probably formed by a mechanism of self-assembly in which the binding sites of actin and myosin participate. A- and I-bands do not develop before the 38th somite stage. The contraction already begins during the 33rd somite stage in the middle of the tubular hear…

The french higher education system faced with the equality-exellence dilemma

1977

International audience

The anomalous magnetic moment of positive and negative muons

1977

Abstract The anomalous g -factor a ≡ ( g −2)/2 has been measured for muons of both charges in the Muon Storage Ring at CERN. The two results, a μ + = 1165910(12) × 10 −9 and a μ − = 1165936(12) × 10 −9 , are in good agreement with each other, and combine to give a mean a μ = 1165922(9) × 10 −9 , which is very close to the most recent theoretical prediction 1165921(10) × 10 −9 . For the experimental results, the total statistical and systematic error is given. The measurements thus confirm the remarkable QED calculation plus hadronic contribution, and serve as a precise verification of the CPT theorem for muons.

Spektroskopische analyse mehrfacher methacrylsäureester von oligo[(2-hydroxy-1,3-phenylen)methylen]en mittels UV-, IR-, 1H NMR- und massenspektren

1977

The structures of two homologous series of oligo[(2-hydroxy-1,3-phenylene)methylene]s completely esterified with methacrylic acid, were spectroscopically analysed. The molar decadal absorption coefficients of ultraviolet absorption maxima of the two homologous series confirm Hunter's relation. The vinylidene, ester, and substitution bands of the infrared spectra as well as the mass spectra agree with the accepted structures. The 1H NMR spectra permit to differentiate between exterior and interior groups of the molecules.

Polymere 3-acryloyloxyalkyl- und 3-acryloyloxyaryl-4-thiazolidone als strahlenschutzsubstanzen

1977

The syntheses of 3-acryloyloxyalkyl- and 3-acryloyloxyaryl-2-phenyl-4-thiazolidones (3a–c) from the corresponding hydroxyl derivatives 2a–c and acrylic acid chloride are described. These monomers were homopolymerized and copolymerized with N-vinyl-2-pyrrolidone by radical initiation. The resulting water soluble copolymers were tested in animals for radioprotective activity and prolongation of efficiency.

Followup of irradiated prostatic carcinoma by aspiration biopsy.

1977

AbstractOf 66 patients with irradiated prostatic carcinoma 53 were controlled regularly by repeat aspiration biopsy every 6 months. Local sterilization was achieved in 43 per cent but the results of combined radiotherapy (endocrine therapy plus irradiation) were only 8 per cent more favorable than those in patients treated by radiotherapy alone. Thus, endocrine therapy is not warranted before the radiation effect is evaluated. Post-radiation treatment should be determined by the clinical and bioptic findings.

Zum Problem der Gewöhnung an Schallreize während des Schlafes

1977

In den bisher veroffentlichten Arbeiten konnte eine Gewohnung, d. h. eine Reaktionsabnahme im Verlauf einer Versuchsreihe statistisch nicht gesichert werden, obwohl in den meisten Arbeiten gegen Ende der Versuche eine geringere prozentuale Reaktionshaufigkeit gefunden wurde. Die Ursache der fehlenden Signifikanz scheint darin zu liegen, dass Signifikanzteste bei der geringen Anzahl der Einzelversuche versagen. Werden die in der Literatur veroffentlichten Werte zusammengefasst, so lasst sich im Verlauf der Versuchsserien eine signifikant haufigere Reaktionsabnahme berechnen.