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B Stumpf

Publications and source records attributed to B Stumpf.

22 records · Page 2Linked to original sources

Gluconeogenesis in kidney cortex slices of the guinea pig. Its relation to acidosis and to calcium.

In contrast to rat kidney cortex the glucogenic capacity of kidney cortex slices from normally treated guinea pigs was very low. Reduction of the pH of the incubation medium by either lowering the HCO3-concentration or by increasing the pCO2 resulted only in varying stimulatory effects on glucose production from endogeneous or exogeneous sources. Considerable rates of net synthesis of glucose from lactate, pyruvate, malate, 2-oxoglutarate, glutamate, and glycerol--but not from glutamine--were only observed in kidneys from animals with prolonged metabolic acidosis. Neither in experiments with normally treated animals nor in those with acidotic guinea pigs the glucose production decreased, when calcium was omitted from the incubation medium. Though glutamine was not converted into glucose, it served as a substrate for ammoniagenesis. On the basis of the presented results it is concluded that species differences exist in the regulation of renal gluconeogenesis.

Acidosis, Renal Tubular↗

Multifunctional instrument for operative laparoscopy: technical, experimental and clinical results in gynaecology.

Whilst endoscopic surgical procedures are getting increasingly more complex, in the various surgical disciplines mono- and bifunctional instruments are only slowly being replaced by multifunctional ones. Therefore a complex, intelligent system was developed, the central part of which is a multifunctional instrument. All basic functions necessary for surgical laparoscopy are integrated and comprise: cutting electrodes (unipolar and bipolar) which can be advanced or retracted pneumatically; coagulation forceps with mechanical control; and irrigation and suction devices. All 5 mm instruments can be used and there is an option for others, such as laser or aqua-dissection. The various functions are controlled via the handle of the multifunctional instrument which is connected to the electronic control unit, the MULTILAP system, which supplies the energy, material, and information flow required. In vivo standardised experiments in pigs were first performed to test the new instrument. Operation time was reduced by more than 20% when compared with the same procedure performed conventionally, during which frequent changing of instruments was necessary. Clinical application, without complications in all 30 patients (uterus preserving procedures or reconstructive tubo-ovarian surgery) confirmed the advantages of a multifunctional device, with optimised cutting and coagulation of vessels more than 1-2 mm in diameter, and reduced duration of operation. Safety and ergonomics were improved. Thus, an electronically controlled instrument with multifunctional working channels for lasers, ultrasound appliances, or mechanical instruments is available for application in all domains of operative laparoscopy.

Animals↗