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Biomedical subjects

P Wittebol

Publications and source records attributed to P Wittebol.

32 records · Page 2Linked to original sources
PubMed1977

The effects of highly selective vagotomy on secretion and emptying of the stomach.

The results of a prospective study of 60 patients with nonobstructive duodenal ulcer treated by highly selective vagotomy show that the gastric acid secretion postoperatively is effectively reduced. Judgment of completeness of highly selective vagotomy is only possible by means of an intragastric pH-metry during operation. The Hollander test answers it insufficiently. In a number of patients, highly selective vagotomy caused a fast initial phase of gastric emptying of porradge. The impression is that the contractional activity of the antrum has the same pattern before and after highly selective vagotomy.

Adult↗
PubMedDate not supplied

Bioresorption of ceramic strontium-85-labeled calcium phosphate implants in dog femora. A pilot study to quantitate bioresorption of ceramic implants of hydroxyapatite and tricalcium orthophosphate in vivo.

Ceramic hydroxyapatite and tricalcium orthophosphate were radioactively labeled with their strontium-85 analogs. Porous blocks of these materials (dimensions 2.5 X 1.25 X 0.5 cm) were implanted into surgically created defects in dog femora. The fate of the implants was studied by roentgenography, radioactivity measurements, histology, and microradiography. The radioactivity over the implant site was followed for 22 weeks. Implants were retrieved after 20-25 and 50-55 weeks. Hydroxyapatite implants were not affected by biodegradation processes, while tricalcium orthophosphate implants were subject to extensive bioresorption (25%-30% in 22 weeks). Resorption debris from tricalcium orthophosphate implants was found in mononuclear phagocytes and multinuclear osteoclastlike cells. The supposition is that tricalcium orthophosphate is transformed into hydroxyapatite in a physiologic environment. Labeling of ceramic calcium phosphate implants with strontium-85 analogs offers an adequate technique to quantitate bioresorption in vivo.

Animals↗
PubMedDate not supplied

Long-term study of large ceramic implants (porous hydroxyapatite) in dog femora.

Blocks of porous ceramic hydroxyapatite (dimensions, 2.5 X 1.25 X 0.5 cm; sintering temperature, 1300 degrees; macroporosity, 56%; average pore size 0.18 mm2) were implanted into surgically created defects in dog femora. The implants were retrieved up to 3.5 years after implantation. The implants were 3.5 years after implantation. The implants were firmly attached to the bone. Histologic evaluation suggests that optimal contact between bone and implant should be provided to accelerate bone ingrowth. Bone growth in the pores reached a maximum level after 35 weeks, at which time about one-third of the pore space was filled with bone. When measuring the relative surface areas of bone and ceramic on histologic slides, no change in ceramic mass could be detected, indicating that hydroxyapatite ceramics are not affected by biodegradation processes. The implants effectively provided a scaffold for bone growth bridging a larger bone defect.

Animals↗