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K Wehmeyer

Publications and source records attributed to K Wehmeyer.

9 recordsLinked to original sources

The pharmacokinetics of two different concentrations of short-acting insulin, intermediate-acting insulin, and an insulin mixture following subcutaneous injection.

To compare the pharmacokinetics of two different concentrations, containing either 40 or 100 IU/ml of short-acting human insulin (Velasulin HM), intermediate-acting human insulin (Insulatard HM), or an insulin mixture (25% short-acting insulin, 75% intermediate-acting insulin; Mixtard HM), three randomized, single-blind, crossover trials were performed using the euglycemic clamp technique. Eighteen healthy volunteers received insulin of either formulation subcutaneously in each of the studies (15 IU Velasulin, 20 IU Insulatard, or Mixtard). The blood glucose levels were maintained constant by glucose infusions. In the trial using Velasulin, the two different insulin concentrations were equivalent regarding the total absorption [area under the curve (AUC) of serum insulin: 126 +/- 28 and 123 +/- 35 mU/l x 12 h for U40 and U100 (mean +/- SD)], but not in regard to the rate of absorption (t max 1.3 +/- 0.4 and 2.4 +/- 1.0 h for U40 and U100). In the case of Insulatard, total absorption was not equivalent (AUC 153 +/- 35 and 128 +/- 37 ml/l x 24 h for U40 and U100), but the rate of absorption was equivalent (t max 4.8 +/- 2.9 and 5.3 +/- 4.6 h). In the Mixtard series, total absorption was equivalent (AUC 142 +/- 32 and 128 +/- 22 mU/l x 24 h), but the rate of absorption was not (t max 2.2 +/- 0.9 and 3.2 +/- 4.2 h for U40 and U100). The glucose requirement was not equivalent in each of the three series.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Skin diving].

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Diving↗

[Centering of eyeglasses with special reference to aspheric single-power lenses].

In the positive power range, aspheric single-power lenses have clear advantages for the spectacle wearer over highly curved spherical lenses in terms of cosmetic appearance and comfort in wear. Correspondingly flat spherical lenses would not be acceptable, due to their dramatically poorer image reproduction properties. Only with an aspheric surface design is it possible to combine a flat lens with optimum image reproduction properties. In order to realize these advantages of aspheric surfaces, the lenses have to be centered in accordance with the ocular pivot point. Several examples are given to illustrate the effects of incorrect centering on the image reproduction properties of both spherical and aspheric single-power lenses. The negative effect of incorrect centering in accordance with the ocular pivot point is clearly far greater with the mathematically much more complex aspheric surfaces than with highly curved spherical lenses. Although the image reproduction quality of the aspheric lens is superior--at least on paper--when it is correctly centered, it is equally true that in practice these lenses quickly prove inferior if incorrectly fitted.

Eyeglasses↗

[Evaluation of air segment plethysmography using computer tomography].

The measurement of tissue volume in the calf area carried out by computer-tomography and planimetry showed a nearly elliptic form, an average bony part of 9.9 ml (9.3%), and an average tissue volume of 97.7 ml (90.7%). When compared with the tissue volume approximation (cylinder formula) the tissue volumes thus specified were too large. The error, depending on the circumference of the calf, was about 5 to 15%. There was a difference of 5% between the venous capacity measured by computer-tomography on the one hand and air segment plethysmography on the other. The reason for this is found in the varying density of veins in the examined area. The application of the sensor on the skin caused an average reduction of 5.4% in total volume and thus in the blood volume of about 59% in the examined area. The pressure-dependent venous capacity was measured with and without application of the sensors on the skin and controlled by computer-tomography. The results showed an average difference of only 2.1%. Thus it is obviously unimportant for the results of the investigation presented, if the venous capacity is measured on the basis of the reduced total volume caused by the application of the sensors on the skin. With regard to the computer-tomographical and planimetrical control and the error of measurement discussed, the results suggest a sufficient precision of the venoextensiometry measuring the pressure-dependent venous capacity.

Blood Volume↗

[Investigation of mesopic vision and sensitivity to glare by means of the new "nyktometer" (author's transl)].

In addition to photopic visual acuity both mesopic vision and sensitivity to glare play an important role in road traffic safety. It is known since the comprehensive investigations by Harms and Aulhorn that mesopic vision and sensitivity to glare are subjected to interindividually different changes with increasing age. 350 persons divided into three age groups were tested with a recently developed "Nyktometer" in order to gain some information about the influence of age on mesopic vision and sensitivity to glare. The results clearly show that both mesopic vision and visual performance in the presence of glare are strongly reduced with increasing age.

Adult↗