No abstract available.
Sclerosis*

The orchid symbiotic fungi were isolated from the roots of Korean native orchid (Cymbidium goeringii) collected and Chinese orchid (C. sinense) obtained from greenhouses. They were identified as a species of Rhizoctonia, based on the sequences of 18r rDNA, the microscopic observations of mycelia, and the symbiotic relationships with commercial orchids. The isolate collected from Chinese orchids was revealed to be a species of Ceratobasidium endophytica, and to be different from the other isolates at the thickness of the mycelia stained in the root cells of Korean native orchids. The other isolates collected from the Korean native orchids were considered to be a species of Tulsanella repens (anamorphic: Epulorhiza repens) or its related one. The physiologic or microscopic variations were oftenly observed among them, but the tendency of grouping these in the 18s rDNA sequences were observed to be consistent with those of the localities collected. The further taxonomical segregating for Korean symbiotic fungi was not made because the information concerned were limited in this moment, but was recognized as based on the sequences of 18s DNA.
Asian Continental Ancestry Group ; DNA ; DNA, Ribosomal ; Fungi* ; Humans ; Mycorrhizae ; Rhizoctonia ; Symbiosis

No abstract available.
Dental Implantation* ; Dental Implants* ; Osseointegration*

No abstract available.
Female ; Obstetric Labor, Premature* ; Pregnancy ; Ritodrine*

No abstract available.
Centrifugation, Density Gradient* ; Humans* ; Spermatozoa*

BACKGROUND: From 1980s the methamphetamine(phillopon) was suddenly spread to our country and it becomes a serious social problem. Although the proportion of transfusion associated hepatitis C declined after introduction of Anti-HCV assay as screening test of blood donors, the overall prevalence of hepatitis C has remained the same, primarily because of increase of the proportion of hepatitis C patients among intravenous drug abusers. So we studied about prevalence of Anti-HCV, and other viral infectious disease transmission by intravenous drug abuse. METHODS: Total 202 drug abusers who had been admitted to Taegu Medical Center in 1994-1996 were tested for the presence of Anti-HCV. Epidemiologic data and histories related to drug use were obtained, as were serum test for hepatitis B, aminotransferase, HIV. RESULTS: The overall seropositivity of anti-HCV was 79.2%. Patients In HCV positive group were significant old age(34.0 yrs) and had long duration of injection(3.0 yrs) and the number of patient who had elevated aminotransferase level were significantly more than HCV negative group(p<0.05). No significant difference in sex, prevalence of HBs Ag and Anti HBc were observated between HCV positive group and negative group. The prevalence of Anti HBc was 52.1% and HBs Ag was 4.2%, but anyone was not detected for AIDS. CONCLUSIONS: The seropositivity of Anti-HCV in intravenous drug users in Taegu, Korea was 79.2%, comparable to that in Europe and U.S.A. This finding suggest that its time to hurry up for medical and public walfare service personal to concern and education of drug abusers, and inview of preventive medical care the need of general public information and education is pressing.
Blood Donors ; Daegu ; Disease Transmission, Infectious ; Drug Users* ; Education ; Europe ; Hepatitis B ; Hepatitis C ; HIV ; Humans ; Korea ; Mass Screening ; Prevalence ; Social Problems ; Substance Abuse, Intravenous

All ceramic restorations have had a more limited life expectancy than metal ceramic crowns because of their lower strength. The relatively lower strength has limited the use of all-ceramic crowns to the areas where occlusal loads are lower. Therefore many researches have been done to increase the strength of all-ceramic crowns. IPS Empress 2 is a new type of lithium disilicate glass-ceramic with enhanced physical characteristics which has been in use clinically since 1998. Previous researches reported that the flexural strength of all-ceramic material was greater than 300MPa, and all-ceramic crowns can be used in staining or layering technique. The objective of this study was to investigate the influence of the thickness of IPS Empress 2 ceramic on fracture strength. Both staining technique and layering technique was investigated. Vita VMK was used as control. For all three groups, five specimens each of 0.8mm, 1.0mm, 1.4mm, 1.8mm, and 2.2mm thickness (a total of 75 specimens) were prepared. Control group: Vita VMK Porcelain specimens were prepared with dentine ceramic and liquid glazing was done. Group I: IPS Empress 2 were prepared with staining technique and stained twice and glazed once. Group II : IPS Empress 2 were prepared with layering technique and glazed after wash firing. The thickness and diameter of the specimen were measured and controlled after specimen preparation. Biaxial Flexure Test (ASTM Standard F394-78) was adopted as this test method produces results least affected by the edge condition of the specimens. Fracture strength was measured with Instron Universal Testing Machine. Conclusions are as follow : 1. The fracture strength was increase in order of control group, test group I, test group II. 2. Fracture strength of the group I(Empress 2 Staining) was 65.54 N in 0.8mm, 155.2 N in 1.0mm, 233.5 N in 1.44mm, 434.5 N in 1.8mm, and 600.1 N in 2.2mm. 3. Fracture strength of the group II (Empress 2 Layering) was 190.0 N in 0.8mm, 283.5 N in 1.0mm, 437.2 N in 1.4mm, 732.0 N in 1.8mm, and 1115.0 N in 2.2mm. 4. No statistical difference was found in flexural strengths according to thickness in a specified group(p>0.05).
Ceramics* ; Crowns ; Dental Porcelain ; Dentin ; Fires ; Life Expectancy ; Lithium

The ideal restorative material should mimic the properties of the tissues it replaces. Dental composite resins have been used widely as restorative materials due to its advantages such as excellent esthetics and ease of manipulation. But inadequate wear resistance has been a major factor limiting the use of composite restorative materials. Improved manufacturing techniques have allowed the development of hybrid composites, with a greater percentage volume filler loading, which have improved physical an mechanical properties. However they are lacking the study wear resistance. The purpose of this study was to evaluate the wear of human enamel against ceromer by the use of a pin-on-disk type wear testers. Discs of ceromer(Targis : Ivoclar, Vivadent, Amherst. NY) and discs of type III gold alloy as a control were used for test specimens. Intact cusp of premolar and molar were used for enamel specimens. The wear of enamel was determined by weighing the cusp before and after each test, and the weight converted to volumes by average density of enamel. Surface profilometer was used to quantify wear of the ceromer and gold specimens. Vicker's hardness tester was used to evaluate the surface hardness of test specimens. The SEM was used to evaluate the wear surfaces. The results were as follows; 1. Ceromer produced less enamel wear than gold(p<0.05). 2. The wear volume of ceromer was greater than that of gold(p<0.01). 3. The hardess of ceromer was lower than that of gold, but there was no correlation between the hardness and wear of the ceromer and gold. 4. SEM analysis revealed that there were many voids and microcracks in the wear tract of ceromer. in gold group, many minute V-shaped grooves were examined.
Alloys ; Bicuspid ; Composite Resins ; Dental Enamel* ; Esthetics ; Hardness ; Hardness Tests ; Humans* ; Molar

All-ceramic restorations have become an attractive alternative to porcelain-fused-to-metal crowns. In-Ceram, and more recently IPS Empress 2 were introduced as a new all-ceramic system for single crowns and 3-unit fixed partial dentures. But their strength and marginal fit are still an important issue. This study evaluated the fracture resistance and marginal fit of three systems of 3 unit all-ceramic bridge fabricated on prepared maxillary anterior resin teeth in vitro. The 3 all-ceramic bridge systems were: (1) a glass-infiltrated, sintered alumina system (In-Ceram) fabricated conventionally, (2) the same system with copy-milled alumina cores (copy-milled In-Ceram), (3) a heat pressed, lithium disilicate reinforced glass-ceramic system (IPS Empress 2). Ten bridges of each system with standardized design of framework were fabricated. All specimens of each system were compressed at 55degree at the palatal surface of pontic until catastrophic fracture occurred. Another seven bridges of each system were fabricated with standard method. All of the bridge-die complexes were embedded in epoxy resin and sectioned buccolingually and mesiodistally. The absolute marginal discrepancy was measured with stereomicroscope at x50 power. The following results were obtained: 1. There was no significant difference in the fracture strength among the 3 systems studied. 2. The Weibull modulus of copy-milled In-Ceram was higher than that of In-Ceram and IPS Empress 2 bridges. 3. Copy-milled In-Ceram (112micrometer) exhibited significantly greater marginal discrepancy than In-Ceram (97micrometer), and IPS Empress 2 (94micrometer at P=0.05. 4. The lingual surfaces of the ceramic crowns showed smaller marginal discrepancies than mesial and distal points. There was no significant difference between teeth (incisor, canine) at P=0.05. 5. All-ceramic bridges of three systems appeared to exhibit sufficient initial strength and acceptable marginal fit values to allow clinical application.
Aluminum Oxide ; Ceramics ; Crowns ; Denture, Partial, Fixed ; Hot Temperature ; Lithium ; Tooth

Gastrofiberscopic findings under direct vision were analysed in 248 patients who were diagnosed as gastric cancer from Feb. 1980 to March 1983 in Department of internal Medicine, Kang Nam Sacred Heart Hospital, Hallym Medical College, Seoul, Korea. (continue...)
Endoscopy* ; Heart ; Humans ; Internal Medicine ; Korea ; Seoul ; Stomach Neoplasms* ; Stomach*