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Biomedical subjects

C Baumann

Publications and source records attributed to C Baumann.

At least 91 records · Page 5Linked to original sources
PubMed1981

Effect of pH on the formation and decay of the metarhodopsins of the frog.

1. Suspensions of membrane vesicles were prepared by sonication of dark-adapted frog rod outer segments. The pH was adjusted to one of twelve values between 5.0 and 9.8; the temperature was 15 degrees C. Each preparation was exposed to a single yellow flash of 120 microseconds duration, and rapid slow changes of absorbance were measured at 475 nm wavelength. 2. Rapid changes consist of a transient rise followed by a diphasic decay to a new level of absorbance which is lower than that before the light exposure. The level of absorbance reached at the end of the rapid changes is lower at lower pH. 3. Kinetic analysis reveals that three reactants take part in the rapid reactions, viz. metarhodopsin I and two isochromic forms of metarhodopsin II named metarhodopsin II' and metarhodopsin II". The kinetics of the reversible transition from metarhodopsin I to metarhodopsin II' are not measurably influenced by the pH of the medium. However, the reversible reaction of metarhodopsin II' with metarhodopsin II" is dependent on pH because metarhodopsin II" is encountered either as a protonated or as a deprotonated compound. 4. Slow reactions are due to metarhodopsin I and to metarhodopsin III. A combined quantitative analysis of both rapid and slow reactions involves a reversible reaction between metarhodopsin II' and metarhodopsin III and a hydrolysis of metarhodopsin II' to retinal and opsin. The scheme employed accounts for the pH dependence of all equilibria although only one of the metarhodopsins reacts directly with protons.

Animals↗
PubMed1980

[Results of curative, distal resection of stomach neoplasms].

Between 1962 and 1971 there were operated 99 patients suffering from gastric cancer. From these, 83% could be controlled as long-term follow-up. The overall survival rate after one year was 68%, after three years 40% and after five years 36%. The patients with tumor-free lymph nodes showed a 5-year survival rate of 49% while of those with tumor-involved lymph nodes only 17% lived longer than five years. The survival rate, especially of older patients (above 60 years), showed with a distal gastric resection compared to a total gastric resection a significant lower postoperative mortality, a better quality of life and a better survival rate. A total gastric resection should only be indicated in cases in which a radical tumor resection could not be realized with a distal gastric resection.

Adenocarcinoma↗
PubMed1980

[Late results after total gastrectomy and reconstruction by the Hunt-Lawrence-Ròdino method].

The operative technique to perform the jejunal pouch--a stomach substitute--according to Hunt-Lawrence-Rodinò is described. This operation should be employed in all cases in which a radical procedure is under consideration. The quality of life is much better than after simple esophago-jejunostomy. The 5-year survival after gastrectomy for carcinoma being 37% and 50% for Zollinger-Ellison syndrome, respectively, a somewhat longer operation is justified.

Gastrectomy↗
PubMed1978

The equilibrium between metarhodopsin I and metarhodopsin II in the isolated frog retina.

1. Rapid and slow changes in the absorbance of isolated frog retinae produced by exposure to brief flashes were studied at temperatures between 5 and 30 degrees C.2. Rapid changes observed at 475 nm consist of a transient increase of absorbance followed by an exponential decay to a new level of absorbance which is lower than before the flash exposure.3. The new level of absorbance determines the initial conditions of slow changes following the rapid ones. At higher temperatures, the loss of absorbance during the rapid changes is greater than at lower temperatures. Accordingly, the slow reactions start at lower levels of absorbance when the temperature is high.4. Quantitative analysis showed that the rapid reactions can be described in terms of two consecutive reactions followed by an equilibrium reaction: the light-controlled formation of lumirhodopsin, decay of lumirhodopsin to metarhodopsin I, and the equilibrium reaction between the metarhodopsins I and II.5. The slow absorbance changes observed in the visible (lambda = 480 nm) are due to metarhodopsin I and to metarhodopsin III. Metarhodopsin I decays during the early phase of slow reactions but can noticeably influence the kinetics at lower temperatures.6. The activation energy of the lumirhodopsin decay is 22.5 kcal/mole, that of the conversion of metarhodopsin I into metarhodopsin II is 30.1 kcal/mole. The entropy change associated with the metarhodopsin I-II equilibrium amounts to +34 cal/mole. K.

Animals↗
PubMed1977

Franz Boll.

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Germany↗
PubMed1977

[Respiratory complications in acute pancreatitis].

The analysis of 12 cases of severe hemorrhagic pancreatitis shows the importance of the detection of an early hypoxemia, which should be treated as soon as possible by a sufficient oxygenation. If the arterial p02 does not improve one should not delay the moment of endotracheal intubation with PEEP.

Acute Disease↗
PubMed1976

The formation of metarhodospin380 in the retinal rods of the frog.

1. The formation of metarhodopsin380 (metarhodopsin II) was studied in isolated frog retinas exposed to intense flashes of 120 mus duration. 2. A rapid increase in absorbance at 375 nm during the flash was followed by a slower absorbance increase in the subsequent dark period. The slower increase showed virtual completion after 5 ms. 3. The fast absorbance increase during the flash was due to the formation of metarhodopsin478. The rate of this reaction was dependent on the time course of the flash and on the decay rate of lumirhodopsin. 4. Kinetic analysis indicates that three consecutive reactions occur: the light-controlled formation of lumirhodopsin, its first-order decay to metarhodopsin478 and the conversion of metarhodopsin478 into metarhodopsin380. At 21 degrees C, the decay constants were 2 X 10(4) S-1 (lumirhodopsin) and 1 X 10(3) S-1 (metarhodopsin478), respectively.

Animals↗
PubMed1976

Biochemical and physiological parameters on the healthy skin surface of patients with common warts.

Biochemical and physiological examinations were carried out on the healthy surface of the skin of 24 test persons who had had contracted common warts during the 2 years prior to examination and on a control group of 46 healthy persons of the same age and sex. The following significant results were obtained: (1) There was a significant reduction in the percentage amount of squalene in the lipids of the skin surface in the patients with common warts as compared with the healthy control persons. (2) The alkali neutralization time in the patients with common warts was significantly shortened as compared with the healthy control group. (3) The degree of moistening of the skin with water was significantly less in the patients with common warts than in the control persons. These results indicate important predisposing factors for common warts.

Adolescent↗