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1.
H. Ono R. Akiyama Y. Sakamoto J. T. Pearson H. Tazawa 《Medical & biological engineering & computing》1997,35(4):431-435
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat.
A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure
the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an
electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG
measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet
is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system.
Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs,
indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of
the velocity of egg movements. 相似文献
2.
3.
K. Hashimoto C. Prince I. Kato M. Ito T. Tazawa J. M. Pelachyk G. R. Mikhail 《Journal of cutaneous pathology》1989,16(1):19-30
A hair matrix tumor showing an unusual tumor cell arrangement was found at the base of a solitary trichoepithelioma. Coexisting with solid epithelial islands and immature hair follicle-like stroma resembling the Verocay bodies of neurilemmoma or "ripplemarks" on waves were found. In other areas myxomatous degeneration of the stroma changed the rippling into a cribriform pattern. In some parts of the tumor there was a dense melanin pigment associated with MEL5 stained melanocytes. S-100 and CD1 (OKT6) antigen stains demonstrated Langerhans cells scattered in the parenchyma and less frequently in the stroma. The majority of tumor cells were considered immature pilar cortical cells because of the following: 1. HKN-6 was strongly positive; 2. a large number of melanocytes were associated with tumor cells in some foci; 3. ultrastructurally immature tumor cells, which had electron-dense tonofilaments and many desmosomes, were transformed without production of trichohyalin granules into semikeratinized cells which showed nuclear degeneration and loss of electron density in tonofilaments. This tumor, however, has not attained the degree of differentiation observed in trichoblastoma (1) another example of an immature cortical cell tumor. Squamous eddy-like or horn pearl-like foci of incomplete keratinization and large keratin-filled cysts were also present within the immature parenchyma, indicating that some immature cells were differentiating toward non-cortical cells, as found in the outer sheath. We would like to designate this tumor "rippled pattern trichomatricoma", a new entity. 相似文献
4.
Clinical application of indocyanine green angiography to choroidal neovascularization 总被引:1,自引:0,他引:1
In order to evaluate the clinical usefulness of indocyanine green video-angiography (IA), the angiographic features of choroidal neovascular membranes (CNM) were investigated in 27 eyes with choroidal neovascular diseases by means of standard fluorescein angiography (FA) and IA. FA showed the existence of CNM in 21 eyes and IA demonstrated evidence of CNM in 19 eyes, as "fan, comb or spotty hyperfluorescence" in the early stage and "leakage" in the late stage. In 6 out of 19 eyes the existence of CNM was shown by IA, while FA failed to identify the precise location and size of CNM due to the masking effect of overlying turbid fluid, massive hemorrhage or a large amount of serous fluid. The results imply that IA has an advantage over FA in cases where FA shows only the sign of occult choroidal neovascularization, and that IA can be applied to neovascular maculopathy as a routine examination. 相似文献
5.
H. Tazawa Y. Hashimoto M. Takami Y. Yufu G. C. Whittow 《Medical & biological engineering & computing》1993,31(2):129-134
Using a flexible piezoelectric film, the authors developed a simple system to determine noninvasively the heart rate of chicken
embryos and hatchlings. The film was piezoelectric polyvinylidene fluoride (PVDF), which is sensitive enough to detect cardiogenic
ballistic movements of the egg (ballistocardiogram (BCG)) and precordial movements of the hatchling attributable to cardiac
contractions (apexcardiogram (ACG)). The BCG could be detected, during the second half of incubation, by placing the egg on
the PVDF film on a soft substrate. The detected signal was found to be a measure of movement velocity. The ACG could be measured
when the hatchling's chest wall made contact with the PVDF film installed in a box in which the hatchling was confined. The
heart rate was counted from the lag time of autocorrelation calculated for a certain time segment (e.g. 2s) of the BCG and
ACG recordings. 相似文献
6.
Clinical heterogeneity of neonatal intrahepatic cholestasis caused by citrin deficiency: case reports from 16 patients 总被引:5,自引:0,他引:5
Tazawa Y Kobayashi K Abukawa D Nagata I Maisawa S Sumazaki R Iizuka T Hosoda Y Okamoto M Murakami J Kaji S Tabata A Lu YB Sakamoto O Matsui A Kanzaki S Takada G Saheki T Iinuma K Ohura T 《Molecular genetics and metabolism》2004,83(3):213-219
A deficiency of citrin, which is encoded by the SLC25A13 gene, causes both adult-onset type II citrullinemia (CTLN2) and neonatal intrahepatic cholestasis (NICCD). We analyzed 16 patients with NICCD to clarify the clinical features of the disease. Severe intrahepatic cholestasis with fatty liver was the most common symptom, but the accompanying clinical features were variable, namely; suspected cases of neonatal hepatitis or biliary atresia, positive results from newborn screening, tyrosinemia, failure to thrive, hemolytic anemia, bleeding tendencies and ketotic hypoglycemia. Laboratory data showed elevated serum bile acid levels, hypoproteinemia, low levels of vitamin K-dependent coagulation factors, and hypergalactosemia. Hypercitrullinemia was detected in 11 out of 15 patients examined. Most of the patients were given a lactose-free and/or medium chain triglycerides-enriched formula and lipid-soluble vitamins. The prognosis of the 16 patients is going fairy well at present, but we should observe these patients carefully to see if they manifest any symptom of CTLN2 in the future. 相似文献
7.
8.
Ultrastructural observation was carried out on neuroblastoma cells in a 4-year-old girl. The nuclei of these neoplastic cells were irregular with occasional cytoplasmic invaginations, and proportionally large with diffusely dispersed chromatin substance. Rare mitotic figures were also present. The cell-to-cell interfaces were relatively simple with only finely wavy membranes but without interdigitations. A few desmosomes were, however, apparent. The cytoplasmic pseudopodes were frequently observed in a limited area of the cell surface and nearly free of organelles. The main findings of the intracytoplasmic organelles consisted of some mitochondrial changes, poor development of Golgi bodies, occasional formation of focal cytoplasmic degradation, and intracytoplasmic Abrillar aggregates. Numerous large round to oval dense bodies encircled by a double membrane were highly suggestive of lipid bodies. The central area of rosette-like cell aggregates was noted to be composed of cytoplasmic processes of neoplastic cells. 相似文献
9.
CD81 nucleotide mutation in hepatocellular carcinoma and lack of CD81 polymorphism in patients at stages of hepatitis C virus infection 总被引:1,自引:0,他引:1
Itakura J Nagayama K Enomoto N Sakamoto N Tazawa J Izumi N Marumo F Sato C 《Journal of medical virology》2001,63(1):22-28
Mechanisms determining the chronicity or the pattern of clinical course of hepatitis C virus (HCV) infections have not been clarified. Recently, CD81 was reported to bind the E2 protein of HCV and was suggested to function as a cellular receptor for HCV. Accordingly, the hypothesis was examined that CD81 polymorphism, if it exists, might correlate with certain clinical courses of HCV infection. CD81 cDNA sequences were determined from peripheral blood mononuclear cells (PBMCs). Twenty-four Japanese subjects were enrolled initially as follows: patients with chronic hepatitis C without cirrhosis (n = 3), patients with cirrhosis (n = 3), patients with cirrhosis complicated by hepatocellular carcinoma (HCC) (n = 3), patients with persistent HCV viremia without ALT elevation (n = 3), those with positive anti-HCV antibodies without evidence of HCV viremia (n = 3), and healthy volunteers (n = 9). In all PBMCs samples analyzed, no polymorphism was found in the CD81 cDNA sequence. The sequence was different, however, from the one reported previously at three nucleotide positions: a transversion to thymine instead of cytosine at nt 1130, a deletion at nt 1206, and a guanine insertion at nt 71. Subsequently, CD81 cDNA sequences from PBMCs and HCC tissue were compared among the other 6 patients with chronic hepatitis C bearing HCC. A comparative study of the CD81 sequences from HCC and PBMCs revealed that various nucleotide mutations existed only in the HCC samples in 3 out of 6 patients. Several mutations in the 3' non-coding region of CD81 cDNA were observed exclusively in HCC tissue suggesting its possible role in hepatocarcinogenesis. Because of the absence of polymorphisms, however, CD81 is unlikely to affect the progression of chronic hepatitis C in terms of chronicity, hepatitis activity, or disease stage. 相似文献
10.