TASK DEFINITION: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
PROBLEM: Abstract: The aim of this study was to achieve more understanding of the mass transfer characteristics of the filmadsorber haemoperfusion device. First, a structural model with mathematical description of the different diffusion steps was developed. Exact quantification appeared very difficult, resulting in insufficient fit of predicted and measured concentration curves. Moreover, the mathematics turned out simple, since the concentration courses could be described with one exponential power. Therefore, a formal model was developed, assuming linear isotherms and adsorption, proportional to the average concentration in the column. With this model predicted in-vitro inlet and outlet concentrations could be fitted to the measured data accurately. A relation between both models is given under the condition of high intraparticle mass transfer, which is allowed in case of powder adsorbents. It can be concluded that structural models do not yield predictive tools for optimization of device geometry. A formal model with two constants determining device performance enables device optimization with the help of some in-vitro experiments.

SOLUTION: Adsorption

PROBLEM: Abstract: The effects of at least three doses of each of five orally administered progestins on estrogen-primed, postmenopausal endometrial biochemistry and morphologic features were analyzed. The progestins tested were norethindrone, medroxyprogesterone acetate (MPA), norgestrel, dydrogesterone, and progesterone. The dose required to elicit responses similar to those seen in premenopausal, secretory endometria was assessed for each of the parameters measured, and the relative potencies were calculated. Potencies, relative to a value of 1 for norethindrone, are L norgestrel 8 (D/L norgestrel 4), MPA 0.1, dydrogesterone 0.02, and progesterone 0.002. The dose of norethindrone required to elicit secretory phase activity was about 0.35 mg/day. These values agree with published data obtained with the use of different methods (delay of menstruation in premenopausal women, endometrial histologic features of estrogen-primed, ovariectomized women).

SOLUTION: Administration, Oral

PROBLEM: Abstract: Seventy-five patients, 80-90 years old, each having approximately three associated diseases, underwent a total of 104 gastrointestinal endoscopies. Of these, 73 were upper (29 emergencies) and 31 lower endoscopies (21 were rigid sigmoidoscopies). There were two very mild short-lived complications; vomiting and bleeding. We found 16 gastric ulcers, 16 duodenal or pyloric ulcers, and 11 cases of esophagitis. Bleeding duodenal (8) or gastric (4) ulcers and polyps or malignant tumors (7) were seen less often. In 34 of 68 lesions the endoscopic and x-ray findings were the same. In the other 34 there were 10 endoscopic failures to identify colonic diverticula, hiatus hernia, and gastroesophageal reflux that were seen radiologically. In 24 patients, diagnoses were not made radiologically, but were recognized at endoscopy. The safety and accuracy of endoscopy in the old and sick does not differ from that in younger patients.

SOLUTION:
Aged