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S Nishida

Publications and source records attributed to S Nishida.

At least 289 records · Page 16Linked to original sources
PubMed1991

[Morphological study of human thyroid papillary carcinoma cells in collagen gel culture].

Human thyroid papillary carcinoma cells (surgical materials) were cultured in a monolayer or a collagen gel system. In the monolayer culture, degeneration and necrosis of cancer cells were observed after 10 days of culture. In the collagen gel culture, degenerative necrosis were observed 14 days culture. In histopathological observation monolayer cells proliferated in pavement-like form without forming any colony. On the contrary, collagen gel culture cells formed branching-type colonies and spheroid-type colonies. Those results suggested that papillary carcinoma cells can be cultured more like in vivo in collagen gel culture than monolayer culture.

Carcinoma, Papillary↗
PubMed1991

[Sudden onset of systemic hypoxia associated with both tricuspid regurgitation and persistent foramen ovale: a case report].

A 33-year-old female who had undergone closure of VSD 20 years before, was hospitalized for sudden onset of dyspnea without history of febrile or traumatic disorder. On admission, she had cyanotic lips and nailbeds but no clubbed finger. Chest x-ray film showed neither lung congestion nor cardiomegaly. Arterial blood gas analysis revealed deep hypoxia (PaO2 = 49.6 mmHg). Echocardiogram clarified massive tricuspid regurgitation (TR) due to chordal rupture of anterior leaflet, small VSD jet stream through the membranous aneurysm and a great deal of R-L shunt on the atrial level through a persistent foramen ovale. Cardiac catheterization data confirmed 35% of R-L shunt. At operation, a torn chordal tendon of anterior leaflet and an adhered septal leaflet to aneurysm of membranous portion of ventricular septum were seen. There were two pledgets, used at the first surgery, at the base of the aneurysm and a couple of tiny holes (VSDs) above and below the pledgets were recognized. Following resection of anterior and posterior leaflet, plication of septal leaflet and closure of VSD, a Xenograft valve (Carpentier-Edwards 29-M) was implanted. Then persistent foramen ovale, 20 x 20 mm in large, was closed directly. Her postoperative course was excellent with disappearance of cyanosis, normalized oxygen saturation in arterial blood and improved activity without dyspnea.

Adult↗
PubMed1991

[Topography of the human ciliary muscle].

The human ciliary muscle of the eye of a 48-year-old male enucleated at surgery for an adenoid cystic carcinoma of the lacrimal gland was studied regarding the morphological characteristics of the anterior apical part of the muscle, including the three-dimensional microstructure. In the anterior serial transverse sections from the most anterior level in which the meridional, radial and circular muscle fibers were recognized, the circular muscle layer anteriorly decreased, whereas the radial muscle layer increased in ratio. Thick muscle fiber bundles immediately below the outermost meridional muscle fiber layer repeated to merge and divide with neighbouring bundles on every side and indicating a complicated structure. In the scleral spur, the apical part of the muscle fiber bundle showed a very thin lamellated layer and terminated between the stromal tissue of the scleral spur indicating a strong interconnection with stromal tissue by a muscle-tendon junctional structure basically similar to the muscle-tendon junction in the striated muscle.

Ciliary Body↗
PubMed1991

[A case report of cystic adventitial degeneration communicating with the hip joint in the external iliac artery].

Cystic adventitial degeneration is an uncommon cause of arterial obstruction. Its etiology is debated. We report a case in which the left external artery was affected and the cystic mass communicated with the hip joint. The findings of this case support the embryonic theory that the articular synovium and adventitial cysts have the same mesenchymal origin.

Constriction, Pathologic↗
PubMed1990

The effects of luminance on affinity of apparent motion.

When a single rectangle is replaced by two flanking ones, or vice versa, one sees split or fusion motion. The motion correspondence in these displays is supposed to reflect the affinity between elements. We examined the effects of the element luminance on the affinity. The results indicated that the affinity did not reflect the luminance similarity; it monotonically increased with increasing the luminance of either element of the matching pair. It was also found that the effects of luminance was symmetric in the time axis. These results were obtained for both long-range and short-range apparent motion. Our findings suggest that the affinity directly reflects the response of the simple motion detectors regardless of the displacement size.

Humans↗
PubMed1990

Method for recording short latency evoked potentials using an EKG artifact elimination procedure.

This paper describes the application of an EKG elimination procedure, previously reported by the authors, to evoked potentials (EPs) recording using a non-cephalic reference. The method consists of three separate steps: data acquisition, EKG artifact elimination, and EP averaging. EKG artifacts are eliminated from the raw EEG by applying a four step procedure to the simultaneously recorded EEG, EKG and stimulus pulse. The steps are: synchronized partition of the raw EEG, EKG averaging, synchronized repetition, and synchronized subtraction of the EKG estimate from the raw EEG. Average EP values are then obtained by averaging the processed EEG using the stimulus pulse as a trigger. Somatosensory evoked potentials to a hand reference, averaged using the proposed method, were compared with those obtained by two conventional averaging methods, and were shown to be more clearly defined. The advantage of the proposed method for recording short latency EP values with a non-cephalic reference is that it requires fewer sweeps and thus takes less time than other methods. The proposed method may also be applicable to the recording of other EP values.

Adult↗
PubMed1990

A method for real-time processing to study recovery functions of evoked potentials.

A new method for evaluating the recovery function of evoked potential (EP) in real time was reported. To record the test response of paired stimulation, the responses to alternate presentation of unpaired stimulus and several kinds of paired stimuli with various interstimulus intervals were averaged respectively and subtraction was made in real time. The EP's to the test stimulus obtained by the proposed method were proved to be accurate even under the changing recording conditions. A formula for computing the recovery correlation factor was derived as a measure of the recovery function of the recorded EP, and the recovery curves for three subjects were obtained.

Adult↗
PubMed1990

Kinetic analyses of creatine kinase release patterns in patients with acute myocardial infarction undergoing emergency coronary arteriography.

To quantify the effects of early reperfusion on the size of infarcts, an enzyme indicator was developed: myocardial creatine kinase (CK) release rate (kr), based on a compartmental kinetics model. In 59 patients with acute myocardial infarction (MI) who received intracoronary thrombolysis therapy in the acute phase, the kr showed a good correlation with the flow condition of infarct-related coronary artery and the time required to reach peak enzyme activity. Apparent serum CK disappearance rate (kd') was estimated by using the method of Norris. The kd' was significantly underestimated in patients without reperfusion, suggesting the presence of prolonged enzyme release from the infarcted area. In 22 of 59 patients, who had a first acute anterior MI (left anterior descending arterial lesion), the correction of cumulative enzyme release by myocardial enzyme release (kr) resulted in a closer correlation with chronic phase left ventricular function. Thus, kinetic analyses of serum enzyme release provide a useful means to estimate the infarct size during intracoronary thrombolysis therapy.

Adult↗
PubMed1990

[Aging changes in ocular tissues and their influences on accommodative functions].

It is well known that the amplitude of accommodation deteriorates with aging. However, it is not clear what kinds of morphological changes of age-dependent deterioration of amplitude of accommodation accompany in the crystalline lens and the ciliary muscle, which are the most important involved tissues in the accommodation mechanism. In the present study morphological changes of these tissues were investigated in relation to the deterioration of the accommodative amplitude. Age-dependent deterioration of the subjective amplitude of accommodation obtained by an accommodometer (VDT Accommodometer NP-200, Toyo-Medical, Nagoya) and the objective amplitude by an autorefractometer with a built-in infrared optometer (NIDEK AA 2000 Accommodometer, NIDEK, Gamagori, Japan) were compared. The objective amplitude was 2-3 dptr less than the subjective amplitude for all ages, but change of both curves with aging were parallel. The crystalline lens measured by an ultrasonic A-scan instrument, Alpha 20/20 (Storz, U.S.A.), showed continuous increase in thickness with aging and by accommodative contraction. The crystalline lens in the fifties was as same in thickness as the accommodatively contracted lens in the twenties but the increasing ratio of lens thickness in accommodative contraction decreased with aging and it reached a minimum in the sixties. Scanning electron microscopy (JSM F-15, JOEL Co, Tokyo) revealed three types of characteristic substructures on the cell surface of the crystalline lens fiber, ie, interlocking protrusion, ball-and-socket junction and microplica or the tongue-and-groove junction. In the lenticular nucleus the microplica was prominent on the cell surface throughout all ages but the ball-and-socket junction was sparse in number. On the other hand, the ball-and-socket junction was well developed on the cell surface in the superficial cortex of the lens. The microplica on the cell surface in the superficial cortex was recognizable but indistinct. The microplica and ball-and-socket junction seemed to shift relative to each other in the deeper cortex of the lens. The interlocking protrusion was recognized throughout the whole lens, but was prominent in the lenticular nucleus. The crystalline lens fibers of advanced age were irregural in shape and the spherical substructure, large and small in size, and frequently formed suggesting the cataractous change. Delicate shift of the ciliary processes after conjunctival application of 4% pilocarpine was confirmed by an angioendoscope (Angio Fiber Imaging System FCA-8000. Fukuda Electronics K.K., Tokyo) which was inserted into the vitreous space of cynomorgus monkey eyes.(ABSTRACT TRUNCATED AT 400 WORDS)

Accommodation, Ocular↗
PubMed1989

Spectral properties of signal averaging and a novel technique for improving the signal-to-noise ratio.

Averaging is one well-known method for improving the signal-to-noise (S/N) ratio of data or a time series, in which small amplitude responses to regularly occurring stimuli are contaminated by noise. We have considered the spectral properties of that process and introduce a new method which further improves the S/N ratio. We also demonstrate that the signal recovered by normal averaging is identical to that recovered by the frequency extraction technique which we propose. A formula for the sums-of-squares of the recovered signal is derived. The success of the frequency extraction technique has been demonstrated on sinusoids, white noise, evoked potentials contaminated by a background EEG, and the EEG recorded with the subject's eyes closed.

Algorithms↗
PubMed1989

Column perifusion system for steroidogenesis in isolated rat adrenal cells.

A perifusion system using a plastic column into which isolated rat adrenal cells had been installed was attempted. After ACTH or cAMP was administered to the column, the corticosterone concentration in the eluate was determined. ACTH in 10(-13) and 10(-12) M did not promote corticosterone production, whereas 10(-11) and 10(-10) M showed a dose dependent production of corticosterone. By iterative infusion of 10(-11) or 10(-9) M of ACTH, very clear responses to restimulation of ACTH were noted. Following the administrations of 10(-3) or 10(-2) M of dibutyryl adenosine 3',5'-cyclic monophosphate (dbcAMP), the production of corticosterone increased dose-dependently. These results suggest that this perifusion system is effective for examining the effects of ACTH or cAMP on steroidogenesis of cells.

Adrenal Glands↗
PubMed1989

In vivo quantitation of autofluorescence in human retinal pigment epithelium.

We measured autofluorescence of the macula with fluorophotometry to evaluate age-related changes in human retinal pigment epithelium. Examined in this study were 35 aphakic eyes of 25 patients, ranging in age from 52 to 87 years, after uneventful intracapsular cataract extraction and 21 normal phakic eyes of 20 patients, ranging in age from 9 to 29 years. Autofluorescence at the macula of aphakic eyes increased in an age-dependent manner (r = 0.514; p less than 0.01) as follows: 15.0 ngEq/ml for the sixth decade (n = 1), 17.2 +/- 4.2 for the seventh decade (n = 11), 21.3 +/- 3.6 for the eighth decade (n = 16) and 24.6 +/- 2.7 for the ninth decade (n = 7). We believe that the autofluorescence originates mainly from lipofuscin in the retinal pigment epithelium, and that the autofluorescence enhanced with age reflects the accumulation of lipofuscin.

Adolescent↗
PubMed1989

Evaluation of the signal-to-noise ratio for average evoked potentials: determination of interstimulus interval and averaging number.

Repetitive stimuli have to be presented to improve the signal-to-noise ratio for the identification of evoked potential of the brain. The averaging method has been widely used for the response to repetitive stimuli. It should be noted that if the stimulus frequency is synchronized with the rhythm of the background noise of an electroencephalogram, the colored noise can only poorly be eliminated by the averaging method. This paper discusses the interstimulus interval of the stimuli and the requisite averaging number from the viewpoint of the S/N ratio of averaging evoked potentials. First, using the a priori information of the evoked potential and background noise, we determine the interstimulus interval of the stimuli. Next, under presentation of the stimulus with the interstimulus interval thus determined, the data of the electrical activity are recorded, and the requisite averaging number is obtained such that the S/N ratio of the average evoked potential becomes larger than the required S/N ratio. The results were applied to the data of the photic evoked potential in response to light-flashes in a healthy male.

Adult↗
PubMed1988

Construction of an evoked potential model expressed by parallel second order components with time lags.

We propose an evoked potential model consisting of a parallel combination of second order systems with time lags. Using this evoked potential model, scalp-recorded photic evoked potentials (PEPs) of three healthy young subjects were analysed, and the PEP waveforms decomposed into five basic waveforms. Generator sources for four components commonly observed in all three subjects are discussed.

Adult↗
PubMed1988

Are fluorescent bodies of Y-spermatozoa detectable in common with mammalan species?

An attempt was made to detect the fluorescent bodies (F-body), using Quinacrine mustard (Q-M) staining in the spermatozoa from eight mammalian species (human, bull, boar, dog, rabbit, rat, mouse, and mastomys) as well as in the cock (used as negative control). Sperm suspension, prepared after rinsing by repeated centrifugation with phosphate buffered saline (PBS), was either stained with Q-M for 24 h or treated with protease and then stained with Q-M for 60 min. The final concentration of Q-M in the mixed staining sperm suspension was 0.025 mg/ml. The examination using a reflecting fluorescent microscope revealed that the F-body found in human sperm was also present in the sperm of all the mammals but not in the cock after 24 h of staining. The enzyme-treated specimens showed higher incidences of F-bodies than specimens stained for 24 h without enzymatic digestion. These findings strongly suggest that the F-body is commonly present in the spermatozoa of many mammalian species.

Journal Article↗
PubMed1988

Distribution of Clostridium botulinum in Japan and in Shinkiang district of China.

Soil specimens obtained from several areas of Japan, which are closely located to or facing the Continental land of China, were examined for the distribution of Clostridium botulinum, especially pertaining to types A and B. A total of 266 specimens of Japan, when cultured, showed no type A or B toxicity, although 30 (11.3%), 4 (1.5%), and 10 (3.8%) of the specimens showed C1, C2, and type E toxicities, respectively. On the contrary, types A and/or B toxicities were shown, by the same method, in 14 of 20 specimens of Shinkiang district, China. The highest number of C. botulinum cells found in one gram of soil specimen was 25 for type A and 10 for type B.

China↗
PubMed1988

Long-term prognosis for patients with variant angina and influential factors.

Two hundred forty-five patients with variant angina were followed for an average of 80.5 months (range, 36-184 months). Survival rate at 1, 3, 5, and 10 years was 98%, 97%, 97%, and 93%, respectively. Survival rate without myocardial infarction at 1, 3, 5, and 10 years was 86%, 85%, 83%, and 81%, respectively. By univarite analysis, ST segment elevation in both the anterior and inferior electrocardiographic leads was the most important factor influencing survival, followed by use of calcium antagonists, left ventricular function, smoking, and alcohol intake. The variables that significantly correlated with survival without myocardial infarction were use of calcium antagonists, left ventricular function, extent and severity of coronary artery disease, coronary artery bypass surgery, and disease activity. Multivariate analysis using the Cox proportional hazards model showed that intake of calcium antagonists, extent and severity of coronary artery disease, and ST segment elevation in both the anterior and inferior leads were significant independent predictors of survival without myocardial infarction. We conclude that long-term prognosis for patients with variant angina is relatively good and that use of calcium antagonists improves it.

Adult↗