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Aus der Auswertung interdiurner Temperaturanderungen wurde in fruheren Untersuchungen auf einen zum hohen Druck gerichteten ageostrophischen Massenflus in der Nullschicht (Nullschichteffekt) geschlossen. Aus der Arbeitshypothese, das die Starke des Nullschichteffekts proportional zum horizontalen Druckgradienten sei, konnten in Ubereinstimmung mit der Erfahrung mehrere atmospharische Erscheinungen gefolgert werden.

Die in der Literatur beschriebene spektroskopische 15N-Bestimmung wird dahingehend variiert, das zur Messung der Intensitatsverhaltnisse der N2-Isotopenmolekel ein Stufenfilter verwendet wird. Die in ihrem Prinzip einfache und schnelle Methode erreicht eine Genauigkeit von ±2%. Arbeitsverfahren sowie Einflusse auf Reproduzierbarkeit und Genauigkeit werden beschrieben.

Iron binding imparts a conformational rigidity and compactness to the ovotransferrin molecule. This appears to cause the inaccessibility of certain antigenic sites to antibody in the formation of antigen-antibody complexes. Iron ovotranseferrin had a lower apparent antigenic valence and formed preferably smaller soluble antigen-antibody complexes that ovotransferrin, as measured by fluorescence polarization, saturated ammonium sulfate precipitation, and sedimentation velocity ultracentrifugation experiments. In primary Ab binding tests and in quantitative precipitin tests, however, both antigens gave similar reactivity. These results and the known identity of the primary chemical structure of ovotransferrin and iron ovotransferrin indicated that conformation differences are responsible for the observed immunochemical behavior. Molecular models, based on hydrodynamic measurements on ovotransferrin, iron ovotransferrin, and antibody molecules, also support this view. The antigenic differences between ovotransferrin and iron ovotransferrin were manifested only in the secondary phase of the antigen-antibody complex formation, emphasizing the need for appropriate secondary phase immunochemical techniques in such studies.

The 14S messenger RNA, which contains poly(adenylic acid), of MOPC 41 (mouse plasmocytoma) immunoglobulin light chain, purified to a single peak as shown by polyacrylamide gel electrophoresis, was used to synthesize complementary DNA with the RNA-dependent DNA polymerase of avian myeloblastosis virus. DNA synthesis is entirely dependent on added RNA template and oligo(dT) primer. Both the size and the concentration of the primer affect the reaction. The product behaves similarly to DNA during centrifugation in cesium sulfate density gradients. It is shown by hybridization that the DNA made is complementary to the purified template, light-chain mRNA. The high specific activity of the complementary DNA should make it suitable for gene-dosage experiments. According to alkaline sucrose gradient analyses, some complete complementary DNA transcripts of the 14S mRNA seem to be made. Oligo(dG) can also function as a primer for DNA synthesis, possibly by annealing to an internal cluster of cytidines in the mRNA, that correspond to the bases coding for amino-acids 119 and 120 of the MOPC 41 light chain.

In fruheren Arbeiten (1, 2) ist uber den Einflus einer variierten N-Dungung, insbesondere einer spaten zur Zeit der Blute verabreichten N-Gabe, auf die Eiweiszusammensetzung des Gerstenkorns berichtet worden. Es konnte festgestellt werden, das mit steigendem N-Gehalt des Kornes dessen verschiedene Eiweise in unterschiedlichem Ausmas vermehrt werden. Zur Ubersicht ist in Abb. 1 die Lokalisation der verschiedenen Eiweise des Gerstenkornes, wie sie durch Extraktion gewonnen werden konnen, schematisch dargestellt und ihr Anteil sowie ihr recht unterschiedlicher Gehalt an der fur die Tierernahrung besonders bedeutungsvollen Aminosaure Lysin in Durchschnittswerten angegeben worden. Der Eiweisgehalt steigt in der Regel von geringen Werten der ausersten Schichten bis auf 30% in der Aleuronschicht an und fallt dann wieder allmahlich uber die kleinzelligen auseren bis zu den groszelligen inneren Schichten des Mehlkorpers ab. Einen ahnlich hohen Eiweisgehalt wie die Aleuronschicht besitzt der Keimling. An spezifischen Eiweisen finden sich im Keimling als „Konstitutionseiweise” Albumine und Globuline und in der Aleuronschicht vorwiegend Globuline, wahrend der Mehlkorper in erster Linie Prolamin und Glutelin als „Speichereiweise” enthalt1 ), die im Weizen als Klebereiweise Trager von dessen guten Backeigenschaften sind, die aber durch ihren relativ geringen Lysingehalt den Futterwert im Futtergetreide etwas herabsetzen.

In einer Ubersicht werden diewichtigsten Verfahren zurprobenchemischen Aufbereitung 15N-markierter Verbindungen wiedergegeben. Im Anschlus daran wird eine bewahrte Mikormethode zur Probenchemie von Stickstoffverbindungen fur die optische Isotopenanalyse des Stickstoffs beschrieben, die auf der Oxydation von Ammoniumchlorid mittels Natriumhypobromit zu N2 beruht und Stickstoffmengen von etwa · 10−6 Mol fur eine Probe benotigt. Aufbau der Apparatur und Arbeitsweise werden eingehend erlautert.

which this study is based is conducted under circumstances approximating those of public and private schools throughout the country; it has traditionally offered a program for Grades IX through XII and has never offered work at the college level. These differences from the situation of the College of the University of Chicago (which accepts students who have completed two, three, or four years of high school and places them, by examination, in its four-year program) invited the statement of principles of general education in a new context. First, with regard to terms: three concepts of secondary education should be distinguished and defined, that is, vocational training, collegepreparatory work, and general education. The first is determined by the needs and demands of various re

(1987). Kurze Originalmitteilungen Dunnschichtehromatographische Trennung von Aminosauregemischen an Ionenaustauscherfolien zur Bestimmung der 15N-Haufigkeit einzelner Aminosauren. Isotopenpraxis Isotopes in Environmental and Health Studies: Vol. 23, No. 4, pp. 153-155.

Die beschriebene Methode besteht aus einer Kombination der Ionenaustauschchromatographie mit der klassischen Wasserdampfdestillation. Die Trennung von Nitrit und Nitrat erfolgt dabei durch selektive Reduktion mittels Eisen-II-hydroxid und eines geeigneten Katalysators zu Ammoniak. Am Ende der Trennung liegt der Stickstoff der N-Verbindungen jeweils als Ammoniumchlorid vor, das direkt fur die emissionsspektrometrische 15N-Analyse einsetzbar ist. Die vorgestellte Methode ist vorzugsweise gecignet fur die Untersuchung der mikrobiellen Ammoniumoxydation (Nitrifikation) mittels der 15N-Tracertechnik. The method described consists of a combination of the ion exchange chromatography with the common steam distillation. Nitrite and nitrate are separated by the selective reduction to ammonia using ferrous hydroxide and an appropriate catalyst. Ammonia liberated is titrated with standard hydrochloric acid and directly used as ammonium chloride for 15N analysis by an emission spectrometer. The method is suitable for ...

The BALB/c myeloma tumor, Y5781, has a high level of mu heavy chain mRNA and kappa light chain mRNA, as suggested by denaturing gel analyses of poly(A)-rich, total polysomal mRNA, and confirmed for the mu heavy chain mRNA by kinetic complexity analyses. Both the mRNA coding for the heavy and light chains appear as very prominent and discrete peaks above the generally polydisperse background of the total polysomal mRNA. This mRNA level appears to be stable through a limited number of subcutaneous passages of this myeloma, providing a potentially useful system for mu heavy chain mRNA synthesis and processing. The mu heavy chain mRNA of this myeloma has been enriched to about 60% homogeneity by physicochemical means. In agreement with a previous report (Faust, C.H., Jr., Heim, I., and Moore, J. (1979) Biochemistry 18, 1106-1119), the following physical and biological properties were observed. The mature cytoplasmic mu heavy chain mRNA is 950,000 daltons, i.e. about 2800 nucleotides, and contains approximately 800 undefined, nontranslated bases. In an mRNA-dependent cell-free system, this mRNA stimulates the synthesis of a single, serologically reactive mu heavy chain-like protein, confirmed by tryptic peptide maps.

In 7 convalescent patients we studied utilisation of a single dose of 15N-labelled glycine. In intervals we estimated total-N, urea-N, NH3-N and their 15N-abundances (urine). The following results were obtained. The peak of ammonium-15N appeared 25 minutes earlier than the peak of urea-15 N. The cumulative elimination of total-15N amounted to 25% of uptake after 24 hours and to 34.4% after 6 days. 12 hours after application 53% of the total amount, excreted within 6 days, were already eliminated. 24 hours after administration 80% of total-15N was urea-15N and 2.8% NH3-15N. Further we found correlations between N-balance (N-application minus excretion) and elimination of 15N-urea: If N-balance got more negative, the amount of cumulative elimination, the portion of urea-15N to total-15N and the percentage of elimination after 12 hours related to 6 days were elevated. That means that in stress condition utilisation of glycine to urea is higher and accelerated. The model seems acceptable, to get information concerning metabolic situation in a simple way.

1. Under stress an increased amount of labelled amino acids is incorporated. 2. Under the conditions of stress amino acids too participate in the process of synthesis. 15N-glycine was used as tracer in a quantity of 0.64 g of amino acid and 24 kcal per kg per day, that is at a 0.027 g per kcal. hour infusion rate, so that the infused 15N corresponded to 75% of the total residual nitrogen in healthy subjects and 57% in operated patients. 3. Sixteen percent of the infused 15N is secreted with the urine of healthy subjects as urine nitrogen, and 57% as urine nitrogen and 4--5% as ammonia nitrogen with the urine of the operated cases. 4. In contrast to normal conditions, under stress a higher percentage of the infused amino acids participates in energy production. 5. Stress enhances uropoiesis as in regards both quantity and speed. 6. No difference in acid-base balance was found in the case of postoperative infusion; urinary and plasma concentrations remained within normal limits.

The longitudinal photoelectric angular distributions of electrons ejected from the K-shell of U (Z=92) converters, by photons of 1384 keV and 6756 keV, have been measured between 3° and 45°. The results are compared with theoretical predictions at these energies.

The quality of esophageal voice and speech after laryngectomy depends on several factors. Negative influences are produced by irradiation, resection of the hyoid bone and radical neck dissection. The factors important in esophageal speech were analyzed, with consideration given to the functional morphology of the pseudoglottis and the reconstructed hypopharynx. Phoniatric, laryngologic and radiologic aspects are considered.

The origin and decay properties of levels in 114Cd, with special emphasis on the quintuplet of states around 1.2 MeV excitation energy, are invesigated both theoretically and experimentally. An almost complete set of reduced transition probabilities B(E0) and B(E2) is established by means of (n, γ) and (n, e−) spectroscopy. Cofiguration mixing between vibrational-like and rotational-like states, extracted from proton two-particle-two-hole (2p-2h) core coupling calculations, is found to be crucial for explaining the peculiar level properties.

The importance of 15N as tracer in medical research is increasing. Since 1965 many results were obtained in cooperation of surgeons (Surgical clinic of Karl-Marx-University; Bezirkskrankenhaus St. Georg, Leipzig) and coworkers of Central Institute of Isotope and Radiation research. Using 3 test models (15N-labelled amino acid solution, permanent infused; 15N-labelled glycine, given as one single dose; 15N-labelled casein, oral given) healthy persons, patients in stress condition and after gastric operations and rats after performing several types of gastric operations were studied. Possibilities of calculations with mathematical models are shown.

IgE has clinical importance because it is responsible for immediate hypersensitivity. Studies of IgE expression in rats appear to contradict current models for immunoglobulin gene expression. To study rat IgE expression at the RNA and DNA levels, we have constructed a cDNA for part of the rat epsilon (epsilon) heavy chain that is expressed by a rat myeloma, IR162. The rat epsilon-chain clone was initially identified by an efficient selection scheme. DNA sequencing of the 580-bp cDNA revealed that it encoded 176 amino acids that were 50% homologous to the human epsilon H chain. The sequence begins near the end of the CH2 domain and ends 31 amino acids into the CH4 domain. Cysteines important for the structure of the human IgE were conserved in the rat epsilon H-chain. The identity of the cloned epsilon cDNA was confirmed by comparison with a portion of the constant region gene for mouse epsilon H chain. The mouse and rat nucleotide sequences were 79% homologous.

Die Haufigkeit pyogener Leberabszesse blieb innerhalb der letzten 6 Jahrzehnte konstant bei 0,29–1,47% der Autopsien [1]. Wegen der prognostischen Bedeutung der Fruhdiagnose und neuer therapeutischer Gesichtspunkte wurden die Krankengeschichten von 27 Patienten analysiert, die zwischen 1974 und 1984 mit dieser Diagnose im Universitatsklinikum Basel hospitalisiert waren. Infolge der uncharakteristischen Symptomatik und der zu Beginn des Zeitraums eingeschrankten Nachweismoglichkeiten von Abszessen mit bildgebenden Systemen erfolgte die Diagnose zunachst vorwiegend intraoperativ oder postmortal. Dies anderte sich entscheidend durch den Einsatz des Ultraschalls und der Computertomographie.

The functional state of the liver can be assessed by oral administration of 15N labelled ammonium chloride (tracer) and subsequent isotope analysis of [15N]urea and [15N]ammonia in urine. Clinical tests based on the ratio of the excess abundances of [15N]ammonia to [15N]urea excreted in urine 3 hours after oral administration of the tracer gave values for patients with liver diseases which differed significantly from these of healthy subjects.

Gamma-ray transitions due to thermal-neutron capture in /sup 73/Ge were measured at ILL, Grenoble, using the curved-crystal spectrometers GAMS 1, 2 and 3, a pair spectrometer and a Ge(Li) spectrometer. Some 750 transitions were identified, of which 450 were placed in a level and decay scheme with the aid of an interactive program. Selected energy regions were scanned with the internal-conversion electron spectrometer BILL, yielding 18 transitions corresponding to delta-rays and sixteen unmatched candidates. The levels up to 4 MeV are presented together with the degree of corroboration obtained from published (p, t) and (t, p) results and ..beta..-decay data.

The 9th observation of esophageal intramural diverticulosis is reported. The findings are compared with those of former publications. Clinically dysphagia is a leading symptom. Suction biopsy proved diverticulosis being the correct interpretation for radiological findings. The etiology is discussed. The change between symptom-free intervals with diverticulosis only and episods of dysphagia by secondary inflammation (reflux esophagitis, moniliasis, stenosis) stresses the importance of such secondary complications. These inflammations can hide the real diagnosis for a long time. The radiological findings are the key for diagnosis, however, they can be very small for years. During this period a diagnosis can only be achieved by knowledge of the disease and the skilful search for early symptoms.

The 15N-tracer technique gives new opportunities to medical research for investigation of normal and pathological nitrogen metabolism. Analysis of 15N kinetic data derived from total nitrogen excretion in the urine allows to calculate quantitatively certain parameters of protein synthesis and protein metabolism. At the same time analysis of serum samples will allow measurement of 15N-nitrogen incorporation into particular protein or non-protein fractions of the plasma. In the study reported here patients with different liver parenchyme lesions (acute hepatitis, chronic active hepatitis, biliary obstruction, cirrhosis of the liver, hepatic coma) were investigated with a standardized 15N-tracer method developed by us. It could be shown, that protein turnover in patients with liver insufficiency is significantly decreased as compared to healthy persons. Decrease of protein synthesis is associated with a still more pronounced decrease of protein catabolism. There are significant differences in dynamics of 15N in patients with hepatic coma as compared to other patients with liver parenchyme disease without portal encephalopathy. Nevertheless, even in hepatic coma 15N incorporation into plasma proteins can be shown. Differences in the 15N elimination kinetics of the non-protein pool between patients with chronic active hepatitis, biliary obstruction and hepatic coma could be found.

Indication and significance of roentgenological procedures referring to esophageal and gastric motility are discussed with special reference to a number of functional disorders. Cinematography and tape-recording are necessary for fast peristaltic motion as in vascular, neurological and myogenic diseases of the upper esophageal sphincter. Pharmacological response may for instance help to differentiate functional from morphological disorders or postoperative complains. Combinations of roentgenological and radioisotopical studies or manometry may be usefull for special diagnostic problems.