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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.

Aus 2-Chlorathyl-trimethylammoniumchlorid 1 wird eine Reihe von Salzen hergestellt, die das gleiche kation enthalten. Weiterhin werden einige nucleophile Substitutionsreaktionen am 2-Chlorathyl-trimethylammoniumkation untersucht. β-Eliminierungen sind sowohl zum Vinyl-trimethylammoniumkation als auch zum Vinylchlorid moglich. Bei der Oxydation von 2-Chlorathyltrimethylammoniumchlorid entsteht Glykokollbetain, bei der Pyrolyse Methylchlorid.

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

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 ...

(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.

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.

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 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.

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.

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.

Cannulation of the papilla has been successful in 144 out of 197 ERCPs. The rate of success increases with the experience of the endoscopist. The intended filling of the pancreatic duct was successful in 87%, of the bile ducts in 64% and of both duct systems in 28%. The correct diagnosis was made in 77% of pancreatic affections, 71% of biliary diseases and in 43% when both duct systems had to be evaluated. 10 ERCP findings disagreed with the final diagnosis, mainly because the distinction between acute and chronic pancreatitis was not correct. The differentiation of chronic pancreatitis from pancreatic carcinoma is not easy and the evaluation of processes localized to the papilla may be difficult. Complications occurred in 6.6%. It is concluded that the ERCP should be limited to regional hospital centers and should be performed only in cases with well defined indications.

The radiological workup of 15 patients with a carcinoid has been evaluated. As 7 of the 15 patients presented for emergency operation, only the remaining 8 had barium studies (7 barium meals and 1 barium enema). Two of the barium meals were even retrospectively, entirely negative. In two others, initially the diagnosis was missed despite radiological signs, which had been overlooked on follow-up films. Fluoroscopic examination of the small bowel would probably have ensured the detection of the lesion. At the time of diagnosis nine tenth of the tumours were already infiltrating and more than half of them metastasizing. The presence of the carcinoid syndrome implies the production of the causative hormones in the liver or the pulmonary circulation. In order to find the primary intestinal carcinoid in a cureable stage- that is, before it has metastasized-, all patients with diarrhoea and repeated bouts of abdominal pain should have a careful follow-up examination of the small bowel. This examination must include fluoroscopies.

This study compares the effect of two amino acid solutions on protein metabolism after injury by measuring nitrogen balance, 15N-elimination, total body protein synthesis and utilisation of administered nitrogen in an experimental study using pigs. Protein synthesis and nitrogen utilisation were determined using a 15N-tracer technique with recourse to mathematical model concepts. The non-surgical control animals had a lower urinary nitrogen excretion, a more favourable nitrogen balance, a higher 15N-retention, greater total body protein synthesis and utilisation of the infused amino acids during infusion of an amino acid solution with a standard amino acid pattern (A) than the operated animals (solution B). Comparison of the post-operative data shows that if solution A is compared with solution B whose amino acid content takes account of changes in plasma amino acid metabolism following trauma, solution B yields the better results in respect of 15N-retention as well as total body protein synthesis and nitrogen utilisation.

By use of stable isotope labeled amin acid 15N-glycine the effects of truncular subdiaphragmatic vagotomy and of pyloroplasty, which are comprised in the method of bionomic gastric operations, were studied separately. The assessment of nitrogen equilibrium in rats after only truncular vagotomy, only pyloroplasty, truncular vagotomy combined with pyloroplasty, and without surgery serving as controls yielded results as following: After truncular vagotomy the 15N equilibrium was worse than in the control animals or after pyloroplasty only. The cause of that is an enhanced nitrogen loss in urine. After truncular vagotomy with pyloroplasty, though, 15N excretion in feces was significantly higher than after only pyloroplasty. It may be concluded from these results that truncular vagotomy is primarily responsible for the disturbances in protein metabolism. Pyloroplasty in combination with truncular subdiaphragmatic vagotomy also causes a higher nitrogen excretion in the feces indeed.