Alteration in Endothelin Receptor-Mediated Responses in Femoral Arteries from Hyperlipidemic Rabbits / 대한정형외과학회잡지

OBJECTIVE: To investigate the roles of ET in the regulation of peripheral vascular tone, we studied the effect of hyperlipidemia on vascular responsiveness in femoral arteries from rabbits with control groups of rabbits and test groups receiving a hyperlipidemic diet. MATERIALS AND METHODS: New Zealand Whites were anesthetized with pentobabital and killed by exsanguination from the femoral arteries. Arteries which were suspended on muscle chambers at their optimal length for contractile properties, were examined. RESULTS: 1. After 14-16 weeks of cholesterol-rich diet, plasma cholestrol and HDL levels were significantly higher in the hyperlipidemic rabbits than in the control rabbits. There was no significant difference in the triglyceride levels between the two groups. 2. The contractions caused by 60 mM KCI in the femoral arterial strips were significantly augmented (P<0.01). The contractile responses to phenylephrine or angiotensin II were also augmented, whereas 5-hydroxytryptamine or U46619- induced contraction was not affected by the hyperlipidemic diet. 3. In control rabbits, ET-1 and ET- 2 contracted femoral arteries in a concentraction-dependent manner, whereas sarafotoxin S6c and IRL 1620 had no effect. 4. Contractions caused by ET-1 and ET-2 were significantly diminished by hyperlipidemia. 5. ET-1-induced concentration-response curves were inhibited by BQ-610, but not affected by BQ-788 in the femoral arterial strips from control and hyperlipidemic rabbits. CONCLUSIONS: These results suggest that ET is involved in the regulation of vascular tone in peripheral arteries and ETA receptor subtypes are mainly present in rabbit femoral arteries. Further more, ET-induced contraction is attenuated in hyperlipidemic rabbit, and the attenuated responses might be caused at least in part by the alteration of ET receptors (e.g. desensitization).

Treatment of the Humeral Shaft Fracture: Comparison between Functional Bracing Technique and Closed Intramedullary Fixation with Functional Bracing Technique / 대한정형외과학회잡지

It has been generally agreed that most fractures of the humeral shaft are best treated non-operatively although occasionally there are indications for primary operative treatment. Recent advances in internal fixation techniques and instrumentation have led to an expansion of surgical indications, and operative treatment produces higher rates of nonunion, infection and other associated complication when compared with closed treatmet techniques. Because of the significant morbidity of the operative treatment, closed intramedullary fixation techniques that provide stability of the fracture site without opening and reduce the postoperative complications, were developed. In this paper we document forty two fractures of the humeral shafts that were treated by functional bracing(Group I: 24 cases) and intramedullary fixation with functional bracing(Group II: 18 cases) between October, 1982 and August, 1986. And the obtained results were as follows: 1. The everage healing time was 9 weeks in the Group I, and 11 weeks in the Group II . 2. The non-union has not been encountered in the Group I, but non-union and delayed union were 4 cases (22.2%) in the Group II. 3. The complication rate was 9 cases(37.5%) in the Group I, and was 12 cases(66.7%) in the Group II, but deep infection did not occured in all cases. 4. The residual angulation more than 5 degrees was 20 cases(83.3%) in the Group I, and was 2 cases(11.1%) in the Group Il. However the results of the group Il were inferior ot the group I, of more proper selection of the patients, more accurate technique and adequate type of nails have been used, the better results will be taken.

A longitudindal study of growth change on the mandibular symphysis and lower incisors / 대한치과교정학회지

The purpose of this longitudinal study was to examine the growth changes of mandibular symphysis and lower incisors with age. The material was 294 lateral cephalometric radiographs taken longitudinally from 6 to 13 year old children, who were not teated orthodontically. The following conclusions seem to be warranted. 1. The sex difference of the measurements of mandibular symphysis and lower incisors were not statistically significant. 2. There were growth increments (2.69mm in boys and 2.08mm in girls) in the total thickness of mandibular symphysis. 3. There were a great change and individual variations on the curvature of anterior border of mandibular symphysis. 4. The chin angle had a tendency to decrease progressively in both sexes. 5. There were growth increments (8.23mm in boys and 7.40mm in girls) in the anterior dental height. 6. The lower anterior teeth tended to incline labially with age.