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Surface structures of SiC epitaxial layers grown on 4H-, 6H- and 15R-SiC (0001) substrates have been investigated using an optical microscope and an atomic force microscope (AFM). SiC epitaxial layers of 5–15 µm thickness have been grown by chemical vapor deposition on 4H-, 6H- and 15R-SiC (0001) Si-face substrates with 0.2–8.0° off-angle. AFM observation reveals that macrostep formation with a submicron periodicity is reduced by increasing the off-angle of substrates, leading to a small surface roughness of 0.18–0.22 nm. The bunched steps with two and three Si–C bilayer heights are dominant for 4H- and 6H-SiC epitaxial layers, respectively, while 15R-SiC epitaxial layers show both two and three Si–C bilayer height steps, reflecting the peculiar stacking structure of each polytype. By optimization of the growth process, the surface defect density has been reduced from 1200–4500 cm-2 to 50–250 cm-2.

Thick (>30 µm) 4H– and 6H–SiC(0001) epilayers have been grown by cold-wall chemical vapor deposition. The increased thickness of a polycrystalline SiC film coated on a graphite susceptor has allowed growth time to be prolonged, enabling thick epitaxy in one growth run. The unintentionally doped epilayers grown with a C/Si ratio of 2 show low net donor concentrations of 2∼5×1014 cm-3. In low-temperature photoluminescence, very strong free-exciton peaks have been observed, indicating the high purity of the epilayers. A high breakdown voltage of 4200 V has been achieved for a 6H–SiC epitaxial pin diode with a thickness of 31 µm.

4H–SiC has been homoepitaxially grown on off-axis 4H–SiC(0001) at 1700°C by chimney-type vertical hot-wall chemical vapor deposition. Mirror-like surface morphology can be obtained with high growth rates up to 21 µm/h. Epitaxial growth under C-rich conditions at growth rates of 10–14 µm/h leads to enhanced macrostep formation but reduced doping and deep trap concentrations of 7.2×1014 cm-3 and 1.3×1013 cm-3, respectively. Good thickness and doping uniformities of 4% and 6%, respectively, are achieved with this growth technique.

The surface of GaAs (110) cleavage faces treated with (NH4)2Sx and SeS2 solutions were studied by scanning tunneling microscopy (STM) and atomic force microscopy (AFM) in air. Sulfur passivation using a (NH4)2Sx solution removes the native oxide and leaves a thin unreactive sulfur layer, while selenium passivation using a SeS2 solution neither removes the native oxide nor produces a selenium‐terminated surface. With sulfur passivation, an atomically flat surface of the GaAs (110) cleavage face was obtained in the STM image. The topographic contrast over the p‐n junction in the STM image obtained with sulfur passivation shows the n region to be higher than the p region, while there was no height difference seen in the AFM image.

Borrmann4型胃癌164例を対象として, 治療成績と背景因子について検討し治療法について考察した. 切除例74例を肉眼形態から, 胃粘膜すうへきが肥大または結節状になった“すうへき型”(G-Type) と幽門部の肥厚が著明な“狭窄型”(P-Type) に亜型分類した. G-TypeでAppleby法を行った症例の成績が良く, 長期生存例を経験している. 術式別の成績では, 胃全摘のうちAppleby法の成績が良く, 治療法として本法を推漿する. P1, P2症例の成績は, 切除例が非切除例より良いが, S3, N3の合併がない場合, さらに良好な成績が期待できることから, P1, P2症例でもS3, N3の合併がなければ積極的に切除し, 他の非治癒因子が残らないように努力する方針である.

By reviewing 122 cases of postoperative death from gastric carcinoma over the past 6 years and 30 autopsy cases of gastric carcinoma, the significance of recurrence and the role of curative surgery were studied clinically as well as from the view point of autopsy.The time lapse between the detection of biological abnormality and the appearance of signs or symptoms was 6.9 months. Patients became symptomatic 4.8 months after the appearance of signs of recurrence, falling into cachexia in 2.9 months.No correlation between the disease-free interval and the relapse interval was apparent (r=0.3866), irrespective of the site of recurrence (liver, r=0.3049; lymph node, r=0.3534; peritoneal dissemination, r=0.3656). The relapse interval in cases with curative surgery was shorter than that in cases with palliative resection when patients had peritoneal dissemination or lymph node metastases, indicating that findings were made intraoperatively.At the time of autopsy, no gross difference between the sites of recurrence was noted, regardless of surgical curability.

同時性に発生した食道胃重複癌切除症例7例を対象とし, その診断, 手術および治療成績について検討した.術前に7例中5例が食道, 胃病変ともに正しく診断されたが, 特に鑑別診断上重要と思われたのは食道癌の胃壁内転移であった.手術々式はリンパ節郭清を考慮し, 胸部食道病変に対しては胸部食道全摘が, 胃病変に対しては病巣がAまたはMに存在する場合, あるいはCに存在し進行癌と考えられる場合には胃全摘術が, Cに存在し早期癌と考えられる場合には噴門側切除が行われた. しかし, 治療成績は不良で7例中5例が術後1年以内に死亡した. また, 2例が術後肺合併症で死亡した点から手術適応の決定は慎重にすべきと思われた.

Electroosmosis and streaming potential measurements were carried out across charged membranes made of collodion and sulfonated polystyrene. Experiments were confined to the range where linear flux/force relationships hold. Saxen's relationship holds between electroosmosis and streaming potential; for porous charged membranes these exhibit an approximate inverse proportionality to ionic mobility at the limit of low electrolyte concentration. Both tend towards zero at the limit of high electrolyte concentration.

We evaluated the results of surgical treatment obtained from 173 patients with gastric cancer with peritoneal dissemination over a 16-year period and studied applications for surgery and the significance of palliative resection. 1) In all groups of P1, P2 and P3 patients, results for resected cases were more favorable than those for non-resected cases, and some, although not many, of the resected P1 and P2 patients survived for three years. 2) Depending on surgical procedure and dissection, the results for cases with subtotal resectin were more favorable than those for cases with total resection, and the results for cases with R2 dissection were more favorable than those for cases with R0-1, dissection. 3) It was highly possible for the lives of P1 and P2 patients to be prolonged by resection, indicating that R2 dissection is favorable. However, the direct mortality for P3 patients was high, and it was impossible to expect prolongation of patients' lives by resection. P3 patients were therefore not considered to be candidates for surgery.

残胃再発癌の再切除症例10例を対象として, 初回手術と再手術時の所見, 術式, 病理組織学的所見, 癌細胞核DNA量の比較検討を行った.初回手術時に切離断端距離が短かく, これが再発の原因と考えられる例が3例あり, 十分な断端距離をとることによる再発予防が重要である.また, 再切除時の病理所見, 核DNA量から見ると病変はいずれもStage IVと非常に進行した状態であり, 更に悪性度も変化してきている可能性がある点を考えると, 再発を早期に発見し治療することが, 治療成績向上につながると考えられた.

Three cases of slowly expanding hematoma are reported. Case 1: A 61-year-old female with a history of bilateral upper lobectomy for tuberculosis 29 years before was referred to our hospital because of a slowly expanding mediastinal tumor shadow on X-ray. Having increased in size by more than 5 times in 3 years, the tumor was resected under the diagnosis of mediastinal tumor. Histopathological study revealed an intrapulmonary hematoma with dilated microcapillaries beneath a fibrous capsule. Cases 2 and 3: A 64-year-old male and a 71-year-old male, both of whom had thoracoplasty for tubercurosis 30 and 31 years ago, respectively, became aware of a slowly growing hemispherical mass at the lateral thoracic wall under the operation scar. The tumors, which were surgically resected, were encapsulated chronic hematomas. Although the mechanism of chronic expanding hematoma is unclear, the growth may be due to increased permeability of the vascular wall or bleeding from the microvessels beneath a fibrous capsule, considering the presence of these dilated vessels. Except for cases with an epidural hematoma, no cases of “chronic expanding hematoma” caused by thoracotomy or thoracoplasty and resected about 30 years later have been reported so far.

A 74-year-old woman had multiple enlarged periaortic nodes with inhomogeneous enhancement on CT. Although a malignancy such as lymphoma was considered, amyloidosis involving retroperitoneal lymph nodes was confirmed on biopsy.