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The surface of a ceria-stabilized tetragonal zirconia polycrystal (Ce-TZP/Al2O3) nanocomposite was sandblasted by alumina particles and veneered with feldspathic porcelain via a conventional condensation method. The part of each specimen containing the interface layer was sliced to ultrathin sections with an argon ion slicer, and these sliced sections were observed using high-resolution transmission electron microscopy (HRTEM). For both interfaces, Ce-TZP/porcelain and Al2O3/porcelain, no transition layers due to abrupt changes in atomic distributions were observed. Besides, the porcelain layers of both interfaces consisted of homogeneous amorphous phases. These results suggested that both Ce-TZP and Al2O3 could be directly bonded to porcelain by Van der Waals forces arising from the close contact between them.

The surface of a ceria-stabilized tetragonal zirconia polycrystal (Ce-TZP/Al2O3) nanocomposite was sandblasted by alumina particles and veneered with feldspathic porcelain via a conventional condensation method. The part of each specimen containing the interface layer was sliced to ultrathin sections with an argon ion slicer, and these sliced sections were observed using high-resolution transmission electron microscopy (HRTEM). For both interfaces, Ce-TZP/porcelain and Al2O3/porcelain, no transition layers due to abrupt changes in atomic distributions were observed. Besides, the porcelain layers of both interfaces consisted of homogeneous amorphous phases. These results suggested that both Ce-TZP and Al2O3 could be directly bonded to porcelain by Van der Waals forces arising from the close contact between them.

Inhibitors of 3-hydroxy,3-methylglutaryl coenzyme A (HMG-CoA) reductase have been reported to decrease the cholesterol saturation index (CSI) in duodenal bile in humans and to prevent formation of cholesterol gallstones in animal studies. We performed a prospective study to evaluate the role of HMG-CoA reductase inhibitors as gallstone-dissolving agents. Fifty patients with radiolucent gallstones in a gallbladder opacifying at drip infusion cholecystography were treated with either 10 mg/day simvastatin plus 600 mg/day ursodeoxycholic acid (group 1, n=26) or 600 mg/day ursodeoxycholic acid alone (group 2, n=24) for 12 months. The ratio of solitary to multiple gallstone cases was 21:29. Plasma lipid levels were assessed and ultrasonographic examination of the gallbladder was performed at baseline and at 3-month intervals during treatment. Duodenal bile sampling was performed in five patients in each group at baseline and after 12 months of treatment. Plasma cholesterol decreased significantly in group 1 but not in group 2. In solitary gallstone cases, no significant difference in dissolution rates was observed between groups 1 (3 of 9, 33%) and 2 (4 of 12, 33%). In contrast, the dissolution rate in multiple gallstone cases was significantly higher in group 1 (12 of 17, 71%) than in group 2 (3 of 12, 25%) (p0.01). Bile cholesterol saturation index was significantly decreased (p0.01) but did not significantly differ between the two groups. These results suggest that combination therapy with simvastatin and ursodeoxycholic acid is more effective for cholesterol gallstone dissolution than ursodeoxycholic acid monotherapy in patients with multiple gallstones.

We have developed a crystalline infrared fiber using silver halide to transmit a CO2 laser beam. The most preferable composition for the fiber was investigated and found to be 43 weight % AgCl and 57 weight % AgBr; the fiber of this composition exhibits the most superior mechanical strength. Then we examined to find the most suitable conditions and method of the fiber extrusion. The fiber thus obtained exhibits superior physical characteristics, a transmission loss as low as 0.2 dB/m, the minimum bend radius of 2cm and so on. We found some weak points of the fiber under high humidity and unfiltered fluoresent light. If the fiber could be protected from the weak points by structuring a cable, it is ideal for medical use.

Ursodeoxycholic acid (UDCA) was administered orally for 12 weeks to 40 patients with chronic type C hepatitis. Patients were randomly assigned to receive UDCA 150 mg/day (n = 20) or 450 mg/day (n = 20). In the 450-mg group, alanine aminotransferase (ALT) decreased significantly ( P P P P

The purpose of this study was to examine the morphlogical changes and the thermal effects of the CO2 laser irradiation on dentin. For this study, eighteen extracted hu man molars were used. In the experiment examining morphological changes, the irradiation power was 1 to 10 watts, the pulse times were 10 to 500ms and the irradiation frequency was 1 to 20 times. On the dentin surface irradiated by CO2 laser under various conditions, the carbonized area became wider, if the irradiation energy increased.But the depth and width of the cavity was the same, when the irradiation power was con stant. the irradiation energy densities were less than 153J/cm2, the dentin surface changed without making any cracking.In the experiment examining thermal effects, dentin blocks, 1.0 and 2.0mm in thickness, of extracted molars were prepared. These were lased by the CO2 laser using 1 to 5 watts at 10ms pulse mode for 30 seconds.The thermal increase transmitted from the lased surface was measured with the thermoco uple. The results indicate that the thermal increase depends on the dentin thickness and is in inversely proportional to the square of the dentin thickness. For example the thermal in crease should not rise more than 5 degrees for 10 seconds, when the dentin thickness is more than 2mm and the irradiated power is less then 2 watts. This result suggests that this laser irradiation may be successfully used in clinical situation as one of dentin treatment tech niques after further clarification of thermal effects on dental pulp.

A 61-year-old man who had experienced epigastric pain for a year underwent an esophagogas. troduodenoscopy (EGD) which revealed a tiny, lobular and uneven-surfaced protrusion (approximately 4 mm in diameter), well demarcated at the base and normal in color, in the duodenal bulb. A biopsy revealed a well differentiated adenocarcinoma. After admission, an endoscopic mucosal resection was performzed for this lesion. The resected tissue was 19 ×14 mm in size and contained a carcinoma measuring 4×3 mm in diameter. Histopathologically, it was a well differentiated tubular adenocarcinoma limited to the mucosa; the lesion had been completely resected. In Japan, 133 cases of early primary duodenal carcinoma have been reported in the literature. However, the so-called minute cancer measuring less than 5 mm in diameter has never been reported before. Dzagnosis, anatomical distribution, and treatment of the reported cases of early duodenal carcinoma were analyzed in this paper.

We studied 25 cases of minute (less than 5 mm in a diameter) superficial depressed neoplastic lesions during the period of March 1990 to September 1991. These depressed neoplastic lesions were recognized by colonoscopy as asteroid redness with surrounding elevation. The thickness and height of the surrounding elevations were modified by air volume. Occasionally, they seemed according to the air volume to be elevated lesions, though their fundamental form was confirmed as being superficial depressed lesions from observations of histopathological sections and using a dissecting microscope. The endoscopic figures were emphasized by sprinkling them with Methylene Blue. All of the minute depressed neoplastic lesions were histopathologically diagnosed as being tubular adenoma. For the purpose of confirming the histopathological character of the depressed neoplastic lesions (n = 25) and distinguishing them from conventional elevated adenomas (n = 71) of the same diameter, we compared the incidences of glandular crowding, nuclear stratification, nuclear pleomorphism and loss of nuclear polarity in two groups. Glandular crowding and nuclear pleomorphism were recognized significantly more often in the depressed neoplastic lesions than in the elevated adenomas. Although most of the minute depressed neoplastic lesions were fundamentally adenomas, because of their unique histopathologic character, they could give new insight into the development of colon cancer.

Cellular and structural gland atypia in lesions of early colorectal cancer removed by endoscopic polypectomy in 101 patients were histopathologically studied. The following results were observed. Cellular atypia was frequently found in lesions with a high rate of nuclear polarity loss and multiple nuclear mitoses (99. 0%). The most frequent findings in the glands with structural atypia was intraglandular glands and crowding of neoplastic glands (85. 1%). Most of the appearances of the cellular and structural atypias showed no marked relationship with the sizes of the lesions, depth of invasion and association of adenoma components. Early cancer had both cellular and structural atypia in 95% of the patients and could be diagnosed by conventional histopathological criteria. However five patients with early cancer showed no structural atypia and were diagnosed as having cellular atypia. These cancers were early intramucosal cancer and four lesions were associated with adenoma components 20 mm or less in size. The loss of nuclear polarity and nuclear pleomorphism may be considered more important than nuclear stratification and mitoses in the diagnosis of early cancer.

Three hepatitis B virus carriers who were HB(e)Ag negative and having normal liver function developed fulminant hepatitis with evidence of HBV replication following intensive chemotherapy for non-Hodgkin's lymphoma. Each was continuously negative for HB(e)Ag. Analysis of the precore region of HBV isolated from each demonstrated that the HBV of each had a point mutation in the precore region that inhibited the synthesis and the release of hepatitis B(e) antigen. This observation suggests that all HB carriers receiving either immunosuppressive or cytotoxic therapy should be monitored closely even if standard assays suggest that viral replication is not present. Sudden enhanced replication of a HBV mutant as a result of such therapy can be a cause of either very severe hepatitis or occasionally fulminant hepatitis.

The hemostatic effects of hemoclipping, the pure ethanol local injection method and the heat probe methods on hemorrhagic gastric ulcers associated with exposed blood vessels, were compared. The locations of the ulcers and exposed blood vessles, as well as characteristics and the severity of the hemorrhage were discussed. The hemoclipping method was used on 59 patients, the pure ethanol local injection on 32 patients, and the heat probe methods on 26 patients. The hemoclipping and pure ethanol local injection methods were effective in all of the patients in whom the exposed blood vessels were present around the margin of ulcers. The efficacy rate was 91%, 92% and 92%, respectively, when exposed blood vessels were found at the base of the ulcer. The efficacy rate was 94%, 100% and 80% for the three hemostatic methods, respectively, when an oozing hemorrhage was present. The three methods had an efficacy rate of 100% when only blood clots were present. The efficacy rate for a spurting hemorrhage was 86%, 71% and 67%, respectively, for the three methods. The hemoclipping and pure ethanol local injection were effective in 100% of slight and moderate hemorrhage cases, while the heat probe method was effective in only 89% of moderate cases. The efficacy rate was 85%, 85% and 83%, respectively, for severe cases. Overall, the efficacy rate was 93% for the hemoclipping method, 94% for the pure ethanol local injection and 92% for the heat probe method, and there was no significant difference between the three methods with regard to the overall efficacy rate.

The clinical efficacy of various methods of endoscopic treatment was evaluated in 70 patients with early gastric cancer. The treatments included using an Nd- YAG laser on 22 patients (2 IIa cases, 3 IIa + IIc cases and 17 IIc cases), a heater probe on 2 patients (IIc) and endoscopic mucosal resection (EMR) on 46 patients (13 I cases, 15 IIa cases, 2 IIa + IIc cases and 16 IIc cases). Laser irradiation and the heater probe method (endscopic mucosal coagulation; EMC), which cause coagulation and necrosis to lesions using heat energy, were found to be successful for well differentiated adenocarcinoma confined to the mucosa even if the size of the lesions was 20 mm and over. Poorly differentiated adenocarcinoma with lesions 20 mm or smaller reoccurred, and only well differentiated adenocarcinoma with infiltration limited to the mucosa seemed to be treatable endoscopically by EMR. Whether or not total resection was possible was determined with respect to the size and site of lesions in patients treated by EMR. Great therapeutic efficacy was achieved when the lesions were 10 mm or smaller and located in the anterior wall or the greater curvature. Piecemeal resection had to be made in a majority of cases when the lesions measured 10 mm or more or were located in the lesser curvature or the posterior wall. Therefore, endoscopic EMR is recommended if the size of the lesions is 10 mm or less, while EMC must also be considered if the lesions are larger or piecemeal resection is required.

Lower esophageal sphincter pressure (LESP) was measured before and after endoscopic injection sclerotherapy (EIS) in 41 patients with esophageal varices in order to evaluate the effects of the therapy on the reflux prevention mechanisms. LESP was measured by the infusion method before, upon completion of EIS and 6 months after EIS. The magnitude of the decreases in LESP were significantly greater in patients who had ulcers following EIS than in those who did not. A close correlation was noted between the incidence of clinical symptoms of reflux esophagitis (such as heartburn and retrosternal pain), ulcer formation and decreases in LESP. This finding suggests that ulcer formation by EIS affects the reflux prevention mechanisms of the lower esophageal sphincter. However, disorders of the lower esophageal sphincter seem, transient and also reversible because decreases in LESP recovered and the patients' clinical symptoms improved within 6 months of the EIS.

Sera and ultrafiltrates (relative molecular mass

Serial hepatic volumetry calculated from the liver area on abdominal computed tomography was performed in 19 patients with fulminant hepatic failure to determine a relationship between liver volume and prognosis. All patients received intensified artificial liver support comprised of plasma exchange and hemodiafiltration using high-performance membranes, and 10 patients survived. Liver volume was significantly larger in survivors than in nonsurvivors, both in an initial volumetry performed at the onset of coma and in subsequent volumetry performed 10–20 days after the onset of coma. The difference became more significant in the subsequent volumetry because of the recovery of liver size in some of the survivors and progressive liver shrinkage in all nonsurvivors. All patients with a liver volume greater than 656 ml at 10–20 days after the onset of coma survived, whereas all but one patient with a liver volume less than that died. Multivariate analysis revealed only liver volume in subsequent volumetry had discriminatory power upon prognosis among six prognostic factors. These observations imply that in order to obtain an accurate prediction of fulminant hepatic failure by hepatic volumetry, serial studies at least until 10–20 days after the onset of coma are necessary.

A 56-year-old female HB carrier developed fulminant hepatic failure with propagation of precore mutant hepatitis B virus following two sessions of intensive chemotherapy for non-Hodgkin's lymphoma. She was treated with interferon and cyclosporin A for the suppression of viral replication and enhanced host immune responses. She recovered from liver failure with histological evidence of marked regenerative activity.

われわれは53歳という比較的高齢者においてIgM型HA抗体が陽性を示した劇症肝炎で救命し得た1例を経験した.症例は男性であり,感冒様症状後トランスアミナーゼ,ビリルビンの増加後III度の昏睡にて入院した.入院後Plasma exchange, THF,ラクチュロース等による治療をおこない,約7病日後に意識は正常レベルとなった.本症はIgM型HA抗体が発病後約50日目でも陽性であった.入院後30病日目の組織所見では肝線維症の状態であった.劇症肝炎は高齢者では一般的に予後が非常に悪いと言われている.われわれの調べた範囲では50歳以上のA型劇症肝炎例は本症を加え5例目であり,その内4例は生存例である.A型劇症肝炎は劇症肝炎の中では比較的予後が良いものと考えられる.これらの諸問題につき文献的考察を加え報告する.