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Long bone injuries in clinical cases are studied by comparison of roentgenograms with a rational mechanical analysis of the injuries. Fractures produced by torsional loads have a spiral shape with a smooth and even surface. Fractures induced by bending loads have uneven and rugged fracture surfaces perpendicular to the bone axis. Long bones are weak in torsion but strong in tensile stress produced by bending. This result corresponds to the clinical fact that a large direct external force is needed to produce a transverse fracture while a spiral fracture is produced by a relatively small torque.  相似文献   
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Some physiological substances, including acetylcholine and nitric oxide, are useful candidates for stimulation of intestinal absorption of drugs. In the present study, we elucidated the ability of epinephrine (Epi) to stimulate the intestinal absorption of drugs. We evaluated the ability of Epi to enhance absorption of macromolecules using dextran (Mw 4000 Da), which is poorly absorbed from the intestine, as a model compound in situ in a closed loop of the rat jejunum. Treatment of the jejunum with Epi resulted in significant increase in absorption of dextran in a dose-dependent fashion. The area under the curve (AUC) from 0 to 4 h in the Epi-treated jejunum was 13-fold higher than that in the vehicle-treated jejunum. The absorption-enhancing activity of Epi was 40-fold higher than that of caprate, a clinically used absorption-enhancer of drugs. In the experimental conditions used in this study, histological injury of the mucosa and perturbation of the mucosal membrane were not observed in the Epi-treated jejunum. Treatment with an antagonist of alpha-adrenergic receptors attenuated the stimulation of intestinal absorption by Epi, and treatment with an agonist of alpha-adrenergic receptors resulted in enhancement of intestinal absorption. While an antagonist of beta-adrenergic receptors enhanced the absorption-enhancing effect of Epi, an agonist of beta-adrenergic receptors stimulated intestinal absorption. These results indicate that stimulation of adrenergic receptors may be a novel strategy for intestinal absorption of drugs.  相似文献   
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OBJECTIVE: To investigate the eruption pattern of the cleft-side canine regarding its pre-eruption position relative to the cleft in bone-grafted (BG) and nongrafted (NonBG) patients with cleft lip and palate. METHODS: Fifty-three patients with cleft lip and palate (21 BG, 32 NonBG) were examined by panoramic radiography and posteroanterior cephalography taken before and after canine eruption. Subjects were categorized into BG, NonBG, and control groups. Canines at the pre-eruption stage were categorized as close to (group 1) or distant from (group 2) the cleft area. The canine angle and its change between the two stages were evaluated. RESULTS: No significant differences were noted between the initial canine angle of the BG and NonBG groups. Although canines in the BG group erupted without a significant change in angle, the canine angle increased significantly (p < .0001) in the NonBG and control groups. In group 1, a greater change in canine angle was noted in the NonBG (p < .05) and control (p < .01) groups than in the BG group. In group 2, no significant difference was noted among the three groups. CONCLUSIONS: In BG patients, a canine located near the cleft appears to erupt at the same angle as it had before grafting. However, in NonBG patients, it erupts more vertically, guided by cortical bone. For canines distant from the cleft area, there is no significant difference in the change in angulation between NonBG and BG patients.  相似文献   
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One mol perchloric acid-soluble fraction (PASF) obtained from ascitic fluid of a patient (blood group B) with metastatic omentum tumor from ovarian cancer was a glycoprotein fraction containing 35.4% carbohydrate and exhibited A, B and Thomsen-Friedenreich (T) activities. This fraction was separated into three fractions, Frs. 1-3, by a gel filtration with Bio-Gel A-1.5 m column. Among these fractions, Fr. 1 which was obtained in a 5.5% yield to PASF, was a glycoprotein fraction with a high molecular weight, 23.3% carbohydrate and A, B and T activities. Other minor fraction, Fr. 2, and the major fraction, Fr. 3, contained 43.2% and 43.9% carbohydrate, but did not show A, B and T activities, respectively.  相似文献   
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