Tooth movement by segment is one of the means which are frequency used in daily orthodontic practice. When we retract or intrude a tooth or teeth, we should recognize the center of resistance of the certain tooth or teeth. There have been many studies about the center of resistance of a single tooth, not so much was about the tooth-segment. At the present study the center of resistance of the maxillary anterior segment is experimentally investigated by using laser reflection technique and metal splints on the human dry skull. The variables of intrusive force magnitude are divided into two groups, 50g and 100g groups. The results were as follows; 1. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors was at the mesial portion of canine crown at the coronal level. 2. The center of resistance of the maxillary anterior segment composed of the central and lateral incisors and canines is between the canine and the 1st premolar crowns at the coronal level.
Bicuspid ; Crowns ; Humans ; Incisor ; Skull ; Splints ; Tooth ; Tooth Movement

Intimal hyperplasia, an abnormal migration and proliferation of vascular smooth muscle cells with associated deposition of extracellular connective tissue matrix, is a chronic structual changes occuring in denuded arteries, arterialized vein and prosthetic bypass graft. This is one of the most important cause of vascular graft failure within the first year after operation. Certain growth factors, particularly basic fibroblast growth factor, transforming growth factor- , and platelet-derived growth factor, are believed to be the cause of the smooth muscle cell proliferation and migration. This smooth muscle cell proliferation and collagen deposition eventually produce intimal thickening with subsequent stenosis or occlusion of the vascular lumen. In order to evaluate the serial changes of injured vessel wall, aortic patch allograft was done in rat, and studied the morphological finding at 1 day, 1, 2, 6, and 8 weeks after graft. The results were summerized as follows; (1) During the early phase after graft, no significant wall changes were seen in the region of the anastomotic site except the presence of acute inflammatory cells with platelet aggregation and thrombus formation. (2) The intimal thickening was apparent by 1 week and was predominantly composed of smooth muscle cells. At the 2 weeks after graft, endothelial cells were partially regenerated to cover the patch graft, and intimal hyperplasia was composed of a mixture of smooth muscle cells and extracellular matrix, mostly collagen. (3) Six weeks after graft, prominent features were production and deposition of collagen rather than proliferation of smooth muscle cells. Reendothelialization over the thickened intima was seen at 8 weeks and the propagation of intimal hyperplasia to adjacent intima of normal vessel was also noted. In conclusion, intimal hyperplasia after vascular injury seemed to be a progressive response of the proliferation and migration of smooth muscle cells and this result might be used for further study about the suppression of intimal hyperplasia.
Allografts ; Animals ; Aorta ; Arteries ; Collagen ; Connective Tissue ; Constriction, Pathologic ; Endothelial Cells ; Extracellular Matrix ; Fibroblast Growth Factor 2 ; Hyperplasia ; Intercellular Signaling Peptides and Proteins ; Muscle, Smooth, Vascular ; Myocytes, Smooth Muscle ; Platelet Aggregation ; Platelet-Derived Growth Factor ; Rats ; Thrombosis ; Transplants ; Vascular System Injuries ; Veins

Tuberculosis affecting only the appendix is exceedingly rare, and tuberculous involvement of the appendix in the presence of tuberculosis elsewhere in the body, e.g., the lung or the gastrointestinal tract, is not common. Tuberculosis of the appendix is not associated with any specific clinical features, and diagnosis is revealed only after histopathological examination. Recently, we clinically experienced a case of tubercular appendicitis on histopathologic examination after an appendectomy for acute appendicitis. This case of tubercular appendicitis is presented with a brief review of the literature.
Appendectomy ; Appendicitis ; Appendix* ; Diagnosis ; Gastrointestinal Tract ; Lung ; Tuberculosis*

No abstract available.
Porphyria, Acute Intermittent* ; Pregnancy*

No abstract available
Adenocarcinoma*

The size of spinal canal is mesured to detect the lumbar spinal stenosis syndrome and expanding intraspinaltumors by CT. This study was desinged for taking accurate measurement of the normal lumbar spinal canal in Koreanadults. The anteroposterior diameter, interpediculate distance and cross-sectional area of lumbar spinal canalwere measured in 110 normal adults. The results were as follows; 1. The window center that showed identical valueconsistent with actual measurement of phantom was between + 160HU and + 240HU and the window width was below +300HU. 2. In anteroposterio diameter, upper part of the canal was larger value than that of middle and lowerparts, but in interpediculate distance, lower part of the canal revealed larger value than that of upper andmiddle parts. There was no significant difference in cross-sectional area. 3. All measurements male were largerthan those of female at all levels of the spinal canal and 42 measurements(58%) were significant statisstically.4. Compared with Americans, Korean showed lower value in anteriopsterior diameter and cross-sectional area buthigher value in interpediculate distance. 5. Above results should contribute to making an another criteria fordiagnosing the lumbar spinal stenosis in Koreans.
Adult ; Asian Americans ; Female ; Humans ; Male ; Spinal Canal ; Spinal Stenosis

Pasteurella multocida, a Gram-negative coccobacillus, is part of the normal oral flora of many types of animals, including domestic dogs and cats. It is the etiologic agent of a variety of infectious diseases, such as hemorrhagic septicemia in cattle or fowl cholera in chiken. Although this is a primary pathogen in the animal world, infection due to Pasteurella multocida in man has been described with increasing frequency recently. The majority of individuals with pasteurella multocida pulmonary infection possess some underlying pulmonary diseases, most commonly bronchiectasis or COPD. With review of literature, We report a young man who developed the empyema caused by Pasteurella multocida.
Animals ; Bronchiectasis ; Cats ; Cattle ; Cholera ; Communicable Diseases ; Dogs ; Empyema ; Empyema, Pleural* ; Hemorrhagic Septicemia ; Lung Diseases ; Pasteurella multocida* ; Pasteurella* ; Pulmonary Disease, Chronic Obstructive

BACKGROUND: Surfactant protein A (SP-A) is importanpt for regulating surfactant secretion, synthesis and recycling. However, It's regulation in vivo is unclear. SP-A has important roles in regulating surfactant met abolism as well as determining its physical properties. Glucocorticoid accelerates the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. METHODS: The authors investigated the effects of glucocorticoid on the accumulation of mRAN encoding SPA and SP-A protein content. A dult rats were given various doses of subcutaneous dexamethasone and sacrificed after 24 hours and one week. SP-A mRNA was measured using a filter hybridization method. The lung SP-A protein content was determined using a double sandwich ELISA assay with polyclonal antiserum raised in rabbits against purified rat SP-A. RESULTS: 1) The accumulation of SP-A mRNA in the dexamethasone treated group 24 hours after 0.2 mg/kg dexamethasone treatment was increased 38.8% compared to the control group. 2) The accumulation of SP-A mRNA in the dexamethasone treated group 1 week after 2 mg/kg dexamethasone treatment was 49.7% higher than the control group(P<0.01). 3)The total lung SP-A level was not altered after 24 hours by the 0.2 mg/kg treatment. The total lung SP-A content one week after 2 mg/kg dexamethasone administration was 373.7% higher than the control group(P<0.005). CONCLUSIONS: Dexamethasone treatment results in an increase in the SP-A mRNA and SP-A protein levels, suggesting that the pretranslational events in vivo may in part contribute to this process.
Animals ; Dexamethasone* ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells ; Gene Expression* ; Lung ; Phosphatidylcholines ; Pulmonary Surfactant-Associated Protein A* ; Rabbits ; Rats ; Recycling ; RNA, Messenger

BACKGROUND AND OBJECTIVES: The endothelium plays an important role in maintaining vascular tone and function. Essential hypertension may be associated with alterations in endothelial function. The effects of antihypertensive agents on endothelial function have not been fully evaluated in human hypertension and data on the forearm circulation of humans are controversial. The aim of this study was 1) to evaluate the endothelial function in hypertensive patients 2) to investigate whether vitamin C administration has benefit on the endothelial function and 3) to determine whether treatment with ACE inhibitor improve endothelial dysfunction in hypertensive patients. MATERIALS AND METHODS: The endothelial function was estimated using venous occlusion plethysmography(VOP) in 8 hypertensive patients and 8 healthy volunteers. The patients in the hypertension group were treated with enalapril, then examined again. The change of the forearm blood flow(FBF) was measured with the acetylcholine infusion through brachial artery and also with intra-arterial vitamin C. The measurement of forearm volume change was repeated for 7 times each stage. RESULTS: Forearm blood flow response to acetylcholine was significantly enhanced with inra-arterial infusion of vitamin C in hypertensive group before antihypertensive treatment(302+/-58 % --< 446+/-43 %). Co-infusion of L-NMMA, an inhibitor of nitric oxide synthase, blunted forearm blood flow response to acetylcholine(Vit C(+; 446+/-43 % --< Vit C +L-NMMA; 229+/-23 %). After antihypertensive treatment with enalapril for 2 months in hypertensive group, endothelium-dependent vasorelaxation (vasodilatory response to acetylcholine) was significantly improved in treated group compared to before enalapril treatment(302+/-58 % --< 643+/-78 %). CONCLUSIONS: Even though the mechanisms leading to depressed endothelial function in essential hypertension remains to be elucidated, our study shows that vitamin C and ACE inhibitor result in demonstrable improvement by a mechanism that is probably related to antioxidant activity.
Acetylcholine ; Antihypertensive Agents ; Ascorbic Acid* ; Brachial Artery ; Enalapril ; Endothelium ; Forearm ; Healthy Volunteers ; Humans ; Hypertension* ; Nitric Oxide Synthase ; omega-N-Methylarginine ; Vasodilation ; Vitamins*

To assess prophylatic antibiotic usage and the value of an intraoperative bile culture in biliary tract surgery, intraoperative bile cultures were taken in 276 biliary surgical patients during the period from Jan. 1991 to Dec. 1995. The results of bile culture, the isolation of organisms, susceptibility of the microorganisms to antibiotics, and the relationship between a positive culture and postoperative complications were analyzed. The positive culture rate was 56.5%, and the highest culture rate(100%) was seen in patients with combined stones in the gallbladder, the common bile duct and the intrahepatic duct. The most common gram negative microorganism was E. coli(44%), and Enterococcus was the most common among the gram positive microorganisms. The effective antibiotics for gram negative organisms were Amikacin, Gentamicin, Tobramycin, and Chloramphenicol; for gram positive organisms, they were Amikacin, Tetracycline, Gentamicin, and Tobramycin in order of effectiveness. The frequency of wound infection was larger in positive cultures(11.5%) than in negative cultures (2.5%), and the risk factors for positive cultures were old age, obstructive jaundice, a high serum SGOT/SGPT level, and previous biliary tract surgery. In conclusion, we recommend that prophylactic antibiotic treatment be done during the perioperative period for old patients with leukocytosis, obstructive jaundice, cholangitis, or a history previous biliary tract surgery. Antibiotic prophylaxis in biliary tract surgery reduces postoperative infectious complications.
Amikacin ; Anti-Bacterial Agents ; Antibiotic Prophylaxis* ; Bile* ; Biliary Tract* ; Chloramphenicol ; Cholangitis ; Common Bile Duct ; Enterococcus ; Gallbladder ; Gentamicins ; Humans ; Jaundice, Obstructive ; Leukocytosis ; Perioperative Period ; Postoperative Complications ; Risk Factors ; Tetracycline ; Tobramycin ; Wound Infection