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Device characteristics, including nonstationary carrier-transport effects such as velocity overshoot phenomena in submicrometergate Si and GaAs MESFET's, are presented in detail by two-dimensional full Monte Carlo particle simulation. Accurate current-voltage characteristics and transient current response are successfully obtained without relaxation time approximation. Moreover, the carrier dynamics influence on device operation is clarified in a realistic device model, compared with the conventional simulation. It can be pointed out that such nonstationary carrier transport is acutely important for accurate modeling of submicrometer-gate GaAs MESFET's, but is not as important for that of Si MESFET's.

Electrical properties of a heterostructure InP/In 0.53 Ga 0.47 - As photodiode have been analyzed numerically. A device simulator, which can handle a heterostructure up to a high voltage operation, was developed for this work. The numerical simulator explains the experimental results obtained regarding photocurrent. The band-gap discontinuities, i.e., 0.22 eV for the conduction band and 0.37 eV for the valence band, were confirmed to be plausible. The photocurrent switching mechanism in the photodiode by bias voltage was clarified through carrier and potential distributions. It was revealed that the photo-excited holes accumulate at the heterointerface, and the switching voltage for photocurrent varies according to the incident optical power level. It is expected that this simulator will be a powerful tool for optimum heterostructure photodiode design.

An application of Monte Carlo particle and relaxation time approximation modeling to quarter-micron Si MOSFETs is presented. Through a comparison between these two nonstatic models and a conventional model, nonstationary carrier transport is shown to dominate in 0.4 mu m or less channel devices, with peak velocities exceeding 1.0*10/sup 7/ cm/s. It is shown that the relaxation time approximation model tends to overestimate nonstationary carrier dynamics, especially the energy distribution. >

A study is made of the mechanism of hemolysis by anionic surface-active agents. It is supposed that the primary site of the hemolytic attack by anionic agents is the protein moiety of the red cell membrane at physiological pH. The role of phospholipid release in hemolysis increases as the PH of the medium decreases.

Heavy ion particle-induced CMOS latch-up is analyzed using a two-dimensional transient numerical simulator. The charge funneling effect during the carrier collection process is found to lower the parasitic bipolar emitter-base potential barrier. This parasitic bipolar action is the main factor initiating latch-up. Latch-up susceptibility is then examined as a parameter of the heavy ion particle incident condition.

Measurements of the cross section, vector analyzing power, iT/sub 11/, and all three tensor analyzing powers, T/sub 20/, T/sub 21/, and T/sub 22/, have been made for the (d-arrow-right, /sup 6/Li) reactions on /sup 12/C and /sup 16/O at bombarding energies of 18 and 22 MeV. The observed large values of the tensor analyzing powers do not agree with distorted-wave Born approximation calculations assuming a one-step alpha-cluster transfer.

Two-dimensional electron gas behavior in an AlGaAs/GaAs heterostructure FET has been analyzed using the Monte Carlo method. In the channel region, it is assumed that the electrons are subjected to a two-dimensional scattering process. In the other regions, three-dimensional scattering rates are assumed. It is predicted that, in an actual device with 1.20-µm gate length, the transconductance of 250 and 450 mS/mm can be attained at 300 and 77 K, respectively. More efficient performance is possible with improvements in the device structure.

Scaling schemes for GaAs MESFET's below the submicron gate length are proposed. The corresponding switching times are calculated accurately down to 0.25µm gate length devices using an ensemble Monte Carlo simulation program. It is demonstrated that the proposed scaled devices offer ultrashort switching time due to the nonstationary carrier transport effects.

Experimental and calculated results are presented for the current-voltage characteristics in GaAs n+-p--n+submicron diodes. It is found from the results that the drift-diffusion equation is a valid description in such short-channel diodes. It is also recognized that the electron velocity in the diodes is considerably higher than that in the long-channel, collision-dominated devices.

Two cases of false aneurysm that occurred in the cheek are described. The clinical and histological findings indicated the lesions were due to hemorrhage caused by blunt and iatrogenic trauma. In addition, a continuous supply of blood into the cystic spaces through small veins or dilated capillaries in the wall was possibly a contributing factor to their pathogenesis. The lesions were successfully treated by surgical excision.

We compared the in vitro antibacterial activities of ceftizoxime (CZX), cefotaxime (CTX), cefmenoxime (CMX), cefoperazone (CPZ), ceftazidime (CAZ), latamoxef (LMOX) and cefotetan (CTT) against 2,729 strains of 11 organisms freshly isolated from 10 medical institutions in Japan between June 1983 and January 1984 and obtained the following results: Against S. pyogenes, LMOX and CTT, which have the methoxy group at the 7 position, were less active than the other drugs. LMOX inhibited 80% of S. pyogenes at 0.78 micrograms/ml; CTT, at 1.56 micrograms/ml; but CZX and CTX inhibited 100% at 0.025 micrograms/ml or lower; CMX, at 0.05 micrograms/ml; and CPZ and CAZ, at 0.20 micrograms/ml. Against H. influenzae, E. coli, K. pneumoniae, P. mirabilis and indole-positive Proteus, these test antibiotics, especially CZX, CTX and CMX, which have the aminothiazolyl methoxyimino group, were potently active. Against S. marcescens CZX and CAZ were more active than the other drugs and against P. aeruginosa CAZ was more active than the other drugs. The test organisms did not tend to acquire resistance to these cephems when our results were compared with the results obtained at the development period.

This report concerned 2 cases (1-month and 8-day-old boy and 5-month and 27-day-old boy) of Riga-Fede's disease. The cases were treated with photopolymerized resin coverage of the incisal edges. Generally, the treatment methods for Riga-Fede's disease are discing and extraction of the traumatized teeth. The photopolymerized resin coverage proved to help in the rapid healing of the ulcerations. This method is useful because it is easy and is able to avoid a false pulp exposure of the hypoplastic natal and neonatal teeth by discing. 7 cases of natal and neonatal teeth were encountered at the Pedodontic Clinic of Niigata University Dental Hospital during 8 years from September 1979 to August 1987. 1) 7 cases were 3 boys and 4 girls, aging from 21 days after birth to 3 months 19 days. 2) Only one baby had a low birth weight. 3) The natal teeth accounted for 6 cases and the neonatal teeth accounted for 1 case. All were lower central primary incisors (5 on the right side, 1 on the left side and 1 bilateral). There were no supernumerary teeth. 4) 5 cases were of hypoplastic teeth. 5) Riga-Fede's disease was recognized in 3 cases. 6) The prognosis was 1 case of shedding, 2 cases extracted and 4 cases remaining. 7) Mesial inclination of the neighboring teeth and narrowness of the extracted space wee observed in the cases where extraction was performed at an early age. 8) Microradiogram and undemineralized specimens of the extracted tooth revealed that the tooth was very thin and mineralization was so poor and there was almost no root formation.

Basic and clinical investigation on the intravenous administration of sulbenicillin in moderate dose (510g daily) was carried out to evaluate its clinical effect in systemic infections due to gram-negative bacilli. The following results were obtained. (1) In human subjects received 5 g intravenous drip infusion, the peak blood levels were found at the end of infusion. In 6 cases with normal renal function (Ccr greater than or equal to 70ml/min.) the peak blood level was 181 mcg/ml on the average and the half-life 1.1 hours, while in 3 cases with impaired renal function (Ccr less than 70 ml/min.) the peak level 216 mcg/ml and the half-life longer than 2 hours. The height of the peak level seemed to be subjected to the duration of infusion. The renal excretion of sulbenicllin was 55.2% on the average both in cases with normal and impaired renal functions. (2) Sulbenicillin, 510g daily divided in 2 doses, was administered to 15 cases including 6 cases with acute pyelonephritis, 3 with acute cystitis, 3 with biliary tract infection, 2 with respiratory tract infection and 1 with acute prostatitis. All the cases except 3 cases with acute pyelonephritis had underlying diseases. Escherichia coli was isolated from 10 cases, Klebsiella from 2, Pseudomonas aeruginosa from 1, and unidentified gram-negative bacilli from 1. Eleven cases responded to the treatment, but 4 cases failed. In 11 cases with susceptible bacteria, 8 cases responded bacteriologically (2 cases recurred), and 3 cases failed to respond. A case with biliary tract infection due to E. coli did not respond to 5 g daily treatment, but responded to 5 g twice daily. Two cases due to organisms which were not inhibited by 200mcg/ml in vitro did not respond to the treatment. (3) A moderate decrease in red blood cell number and hemoglobin content was observed in one case. A transient increase in transaminase and alkaline phosphatase level was observed in other cases.

Clinical efficacy and safety of SM-4300, a newly developed human immunoglobulin preparation for intravenous use, were evaluated in 11 patients with severe infectious disease which are resistant to antibiotic therapy in the combined use with the antibiotics. Clinical effects of SM-4300 wee excellent in 1 case, good in 5 cases, fair in 1 case, poor in 1 case and unevaluable in 3 cases. The efficacy rate was summarized as 75%. Bacteriological responses were eradicated in 1 case and unknown in 10 cases. No side effects and abnormal laboratory findings due to SM-4300 were observed in this investigation.

Idiopathic hypoparathyroidism is characterized by a deficiency of the parathyroid hormone, origin unknown, and causes a low serum calcium and a high serum inorganic phosphorus. This report concerns a clinical observation of a case of idiopathic hypoparathyroidism. This case was examined from the dental point of view. The findings were as follows: 1. The roentgenographic findings revealed that there was no demonstrable abnormality concerning bone age indicated between the ages of 5 and 6 years. 2. Severe dental caries were noted in the deciduous teeth and the permanent teeth. 3. Hypoplasia and hypocalcemia were recognized in most of the permanent teeth. 4. Large pulp chambers were observed in the deciduous teeth and the permanent teeth, and thickening of the lamina dura was observed in the permanent teeth. 5. The histological findings of the extracted deciduous teeth and the upper right first molar were such that: (1) there was hypoplasia and hypocalcemia in the dentin of deciduous teeth, and there were multiple resorptions in the cementum. (2) there was hypoplasia in the enamel of the upper right first molar. 6. Electron probe microanalysis of the upper left second molar revealed that the degree of mineralization and concentration of Ca, P and Mg in the dentin of the root showed a lower intensity than in the dentin of the normal one. 7. It was assumed from the dental point of view that this hypoparathyroid condition first appeared at about 11'months approximately 18'months of age.

A case of extracalvarial meningioma was reported. 75-year-old man was admitted to our department on November 11, 1974 because of a slowly growing tumor in the right frontoparietal area. The tumor was ovoid and 15x13 cm in size, protruding 5 cm above the skin level, and covered by the normal scalp. Neurological and electroencephalographic examination were negative. Spinal tap showed an opening pressure of 90 mm of water and clear CSF with 62 mg/dl of protein content. Plain roentgenogram and laminagram of the skull revealed both osteolytic and osteoblastic change in the outer and inner table of the skull just beneath the tumor. A right external carotid angiography disclosed a homogeneous extracalvarial tumor stain supplied by the superficial temporal artery and draining into the superficial temporal vein. A right carotid angiogram showed a 1 cm thick avacular area. The segmentally occluded superior sagittal sinus was displaced inward together with bridging collateral channels. Radiologically these picture corresponded to "intracranial non-globoid shape or avascular meningioma" discussed by Huckman et al. The tumor was well-circumscribed, encapsulated and loosely adherent to the periosteum and the skull except for a small portion through which the tumor was communicated with its intracranial part. Histological examination revealed that it was a typical endotheliomatous meningioma. This case should be allocated to the transitional or intermediate type between Lopez II and III type. In the schematical presentation (Fig. 6) we tried to readjust the rather confusing concept and classification of the extracalvarial meningioma.

To assess whether surgical procedures have fulfilled patients' expectations, questionnaires were sent to 41 patients who had undergone surgical-orthodontic correction of skeletal Class III malocclusions. Ninety per cent of the patients answered that they were satisfied with the results in regard to their chief problems and 85% had improved masticatory function. A favorable change in appearance was recognized by 24 patients, whereas 15 patients noticed no major changes, and two were displeased with the changes. Patients' expectations were not always satisfied despite evident improvement by objective standards. Factors affecting their satisfaction with the results of the surgery are discussed.

In addition to replacement therapy with antihemophilic factor (AHF), its concentrated solution was used topically after dental extractions in hemophilic patients. The results, compared with that of the control extraction sites in the same patients, indicated that the topical application of AHF is effective in producing rapid and tight clot formation and in reducing postoperative oozing of blood.

Clinical studies and serum levels on tobramycin (TOB) using intravenous drip infusion were carried out and the following results were obtained. 1. Clinical results Nineteen patients with various infections including 11 respiratory tract infections, 7 urinary tract infections and a wound infection were treated with TOB 20-60 mg b.i.d. and t.i.d. by intravenous drip infusion and for 1 hour during 4 to 16 days. Clinical effects were excellent in 10 cases, good in 4 cases, fair in 2 cases and failure in 3 cases. It was 73.7% of the efficacy rate of the drug. Side effects were observed in 2 cases of oliguria and increase in BUN, S-creatinine and S-potassium. 2. Serum levels of TOB Serum levels of TOB administrated 30 or 60 mg intravenous drip infusion for 1 hour were measured in first and final administration of 8 patients. The peak serum levels were 3.1-5.0 micrograms/ml at the end of infusion in first 60 mg administration of the drug, and 3.8-5.3 micrograms/ml in final 60 mg administration of the drug.

C-AMOX--long acting amoxicillin preparation (gastro coating 3, enterocoating 7)--has been investigated to give following results. A pharmacokinetic study of C-AMOX was conducted in 6 healthy male volunteers in postprandial state (30 minutes after light mean). The levels of 1.8--2.5 micrograms/ml in blood was detected for 6 hours after 500 mg dose orally. It was seemed to be long acting amoxicillin in blood levels. And, the calculated data of AUC of C-AMOX was 15.17 micrograms . hr/ml administered 500 mg dose, and 14.33 micrograms . hr/ml of AMPC twice 250 mg doses, respectively. The urinary excretion rate was 56.1% of the dose during 10 hours. Sixty-six patients with respiratory tract infections, urinary tract infections and others were treated with C-AMOX 0.5 g twice daily for 4--7 days mainly. Thirty one patients of all were cured excellent, 27 were good, 4 were fair and 4 were poor. The global efficacy rate was 87.9%. Only 1 patient was occurred diarrhea, and no abnormal laboratory finding was observed.

16 cases of odontoma (male: 12, female: 4) in young patients from 1 year 2 months to 14 years of age at the Pedodontic Clinic of Niigata University Dental Hospital in a recent 9 year period were investigated clinically. As for the pathologic histology, 12 cases were of the compound type, 2 were of the complex type, 1 was of the intermediate type between compound and complex, and 1 was of ameloblastic fibro-odontoma type. 9 cases occurred in the maxilla, 7 cases occurred in the mandible. Most of the compound type were observed in the area of the maxillary incisors and cuspids, and the complex type cases were noted in the anterior part of the maxilla. In many cases, there were clinical symptoms such as retarded eruption. Some cases of odontoma in children were small in scale and showed a low degree of calcification. Therefore they showed a tendency not to be found out at radiography, and it is difficult to diagnose them as odontoma. By finding odontoma prematurely and removing it in time, the retarded eruption teeth were able to erupt spontaneously or to be guided to a normal position.