Fixation strength of interference screw fixation in bovine, young human, and elderly human cadaver knees: influence of insertion torque, tunnel-bone block gap, and interference.

A failure analysis of interference screw fixation was performed to test the hypothesis that bovine and/or elderly human cadavers are appropriate models for bone-patellar tendon-bone anterior cruciate ligament (ACL) reconstruction fixation studies. Failure mode is an important criterion for validating experimental models. The bovine, young human, and elderly human failure loads were 799 +/- 261 N, 655 +/- 186 N, and 382 +/- 118 N, respectively, and the failure modes were 75%, 69%, and 30% tissue failures, respectively.

[Anesthesia and medical responsibility. Principles].

Anaesthesia exposes the practitioner to the obligation of being answerable for his responsibility if he commits an error which leads directly to damage to the patient. He can be forced to pay compensation for the damage. Quite apart from this, there is also the unpleasant process of being called before a disciplinary hearing for "involuntary injury".

Plaque fluid pH, calcium and phosphorus responses to calcium food additives in a chewable candy.

Fourteen subjects between 7 and 17 years of age with an equal distribution of low and high caries activity were given: (1) a 10% sucrose rinse, (2) a reference candy, (3) a reference candy with 3% dicalcium phosphate dihydrate, and (4) a reference candy with 0.75% calcium lactate on four different occasions. Plaque samples were collected before and at 15-min intervals after the sucrose rinse or food challenge for a period of 1 h on each occasion.

Changes in water proton relaxation times and in nuclear to cytoplasmic element gradients during meiotic maturation of Xenopus oocytes.

Fully grown oocytes 1.2 mm in diameter were removed from Xenopus laevis ovaries and were exposed to progesterone (2.5 micrograms/ml in Ringer's solution) to induce completion of the first maturation division or germinal vesicle breakdown (GVBD).

Evidence for structuring of water in growing oocytes: an X-ray microanalysis and nuclear magnetic resonance study.

Energy dispersive X-ray microanalysis measured the Na, K, Cl, P, Mg, S and Ca contents (mM/kg dry weight) in the nucleus and yolk-free cytoplasm of growing Xenopus laevis oocytes quick frozen in the ovary. Nuclear magnetic resonance measurements of T2, the transverse relaxation time of water protons, were obtained on small immature oocytes and on large, fully grown oocytes. Changes in the nucleus and cytoplasmic content were observed for all elements except for Ca.