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631.
The expression of cytokeratins and involucrin varies greatly in different epithelia, and this raises the possibility that detailed analysis of these epidermal proteins might provide a means of identifying various skin tumours. The present study was conducted to determine the immunohistochemical distribution of cytokeratins and involucrin in calcifying epithelioma of Malherbe, in order to elucidate the nature and differentiation of this tumour. To correlate the immunohistochemical profile with the most frequest histological patterns, we categorized the basophilic, transitional, shadow, and squamoid cells, and the shreds of keratin. Comparative studies with normal skin showed that the shadow and transitional cells corresponded to hair cortex cells, the squamoid cells to the outer root sheath, the basophilic cells adjacent to the stroma to the outermost cell layer of the outer root sheath between the lower permanent portion and upper transient portion of the follicles, and the basophilic cells adjacent to the transitional cells to the hair matrix. The expression of cytokeratins in most shreds of keratin was similar to that in squamoid cells. Calcifying epithelioma was, therefore, shown to be composed of tumour cells differentiating into both the hair cortex and outer root sheath. These tumour cells were differentiated from basophilic cells, which showed the same staining patterns as the outermost cell layer of the outer root sheath between the lower permanent portion and upper transient portion of the hair follicles, supporting the hypothesis that the keratinocytes in the outermost cell layer can differentiate into the transitional portion of the follicle and anagen hair. 相似文献
632.
KEIKO SHISHIKURA MAKIKO OSAWA HARUKO SUZUKI YOSHITO HIRAYAMA YUMI ARAI SAWAKO SUMIDA RIEKO TAKAHASHI YUKIO FUKUYAMA 《Pediatrics international》1994,36(2):186-193
The variable clinical courses of three cases of congenital fiber type disproportion (CFTD) over a period of 10 years are presented. All showed improvement in early childhood, but subsequently, varying degrees of deterioration were noted: specifically, marked deterioration in case 2 and decreased muscle strength in case 3. Maximal motor function levels were attained differently among the cases. Histological findings included type 1 fiber hypotrophy and increased internal nuclei in common in all cases. Fine structural changes, such as patchy areas of myofibrillar degeneration, were noted in cases 1 and 2 (second biopsy), and cytoplasmic bodies were seen in case 2 (second biopsy). Myotubes were noted in case 3. The degree of cyto-architectural changes did not correlate with clinical severity. The heterogeneity of CFTD is also discussed. 相似文献
633.
Abstract This paper reviews the present situation of suicidal behavior in Japan. Although the suicide rate among the younger generation has been decreasing steadily, that among elderly Japanese has been high. In addition, it is expected that the elderly population in Japan will increase more rapidly than in other countries in the 21st century. This paper highlights the problems of suicidal elderly in Japan, by focusing on characteristics of their psychopathology, and it proposes an integrated model for suicide prevention. Accurate knowledge about suicide crisis in the elderly and appropriate countermeasures should be acquired by every individual in the community, and efficient social support networks should be established. The long-term objective should be to create an environment in which senior citizens can contribute to the community to the best of their ability, and every effort should be made to decrease the social stigma against old age and suicide. 相似文献
634.
Alternation of QRS Morphology and Effect of Radiofrequency Ablation in Idiopathic Ventricular Tachycardia 总被引:2,自引:0,他引:2
TAKASHI WASHIZUKA YOSHIFUSA AIZAWA MASAOMI CHINUSHI NAOKI NAITOH TAKEFUMI MIYAJIMA YORIKO KUSANO HITOSHI KITAZAWA HIROHIDE UCHIYAMA KAZUYOSHI TAKAHASHI AKIRA SHIBATA SEIICHI MIYAJIMA MASAHITO SATOU 《Pacing and clinical electrophysiology : PACE》1995,18(1):18-27
We performed electrophysiological studies in 13 patients with idiopathic VT and attempted radiofrequency (RF) catheter ablation in 4 of them.Results: VT was induced by programmed stimulation in all patients and the mean cycle length was 363 ± 58 msec. In 8 of 13 patients (62%), alternation of either the cycle length and/or morphology of VT was observed. Transient entrainment was achieved in all patients by rapid pacing from the right ventricular outflow tract so reentry was considered the underlying mechanism of VT. The site of earliest activation (EAS) during VT was located at the apicoposterior portion of the left ventricular septum and used as the target site for RF catheter ablation. Spikelike presystolic activity was detected 20–40 msec prior to the large deflection of the local electrogram in four patients. VT was terminated by a few seconds of RF current in all four patients, but subsequently new VTs with a slightly different morphology were induced in three of them and re-mapping showed a shift of the EAS. After additional RF ablation at the new EAS, VT was no longer induced. No complication was noted and VT did not recur during a follow-up period for a mean of 9.3 ± 5.2 months.Conclusion: RF catheter ablation seems useful and safe for idiopathic VT. The alternation of QRS morphology and the findings at the time of catheter ablation suggest that an alternative pathway or multiple exits may be present in some patients with idiopathic VT, because the change in VT morphology was associated with a shift of the EAS. 相似文献
635.
YOSHIFUSA AIZAWA HITOSHI KITAZAWA TAKASHI WASHIZUKA KAZUYOSHI TAKAHASHI AKIRA SHIBATA 《Pacing and clinical electrophysiology : PACE》1995,18(4):663-672
Ventricular tachycardia (VT) was entrained with rapid ventricular pacing outside and within the zone of slow conduction (SCZ), and the conductive properties of the reentrant pathway were compared between the two pacing sites. Underlying heart diseases were old myocardial infarction (n = 2), postoperative tetralogy of Fallot (n = 1) or double outlet of the right ventricle (n = 1), dilated cardiomyopathy (n = 1), and pulmonary regurgitation of unknown cause (n = 1). Rapid pacing was continued for 5–10 seconds, and the time interval from paced stimulus to the entrained electrogram at the exit from SCZ (St-Ex) or to the QRS complex (St-QRS) was measured. Rapid pacing was performed at three or more cycle lengths after a decrement in steps of 10 msec. During rapid pacing outside of SCZ and entrainment of VT, constant fusion and progressive fusion were observed, and St-Ex and St-QRS showed the same response pattern: either a frequency dependent prolongation in 4 of 7 VTs or a constant time interval in the others VTs. When rapid pacing was attempted within SCZ, the response of the time intervals from paced site to the QRS (St-QRS) was the same as those observed during pacing outside SCZ except for one VT. In VT with repaired tetralogy of Fallot, the frequency dependent prolongation was observed during pacing from outside of SCZ but not within SCZ. Diseased myocardium extending widely into the outflow tract of the right ventricle may be responsible for the frequency dependent prolongation of St-Ex. In conclusion, the conductive property of the reentrant pathway might be assessed by observing the response patterns of St-Ex or St-QRS interval during transient entrainment of VT outside of SCZ, but exceptions may exist. 相似文献
636.
Kan KOBAYASHI Shin-ichi IWASAKI Keiichi TAKAHASHI Minako UENO Azuma IGARASHI Hiroshi NAGAI Kazunori SUZUKI Tamio KATSUYA 《Congenital anomalies》1985,25(3):165-174
ABSTRACT The purpose of this study is to ascertain possible cytological effects of vitamin A administration to pregnant mice on the fat-storing cells (Ito cell) in the fetus liver. Though many external anomalies were occurred in the fetus when vitamin A was given once on day 8 of gestation, it is conceivable that the appearance of these teratogenicity may not be concerned in Ito cell because liver had not yet developed at this stage. When vitamin A was given once a day for four days consecutively from day 14 to day 17 of gestation little external anomalies were appeared. By electron microscopy, cytological changes were found in Ito cell, especially the number of lipid droplets in the cytoplasm conspicuously increased. This proved that vitamin A administered to the mothers was carried into the fetuses through the placenta and Ito cells of the fetus liver had an ability to absorb vitamin A at the late stage of pregnancy. 相似文献
637.
Effects of acute and chronic treatment of rats with chlorpromazine (CP) and phenobarbital respectively on the N-oxidase and the N-demethylase activities of liver and brain were studied. The acute treatment with CP caused a reduction in body weight, but no change in liver weight. The measured enzyme activities of liver homogenates decreased by 12–19 per cent compared with controls. These decreases were not statistically significant in every age group, but tended to be comparatively marked accompanied with aging. Phenobarbital produced no significant change in body weights, but brought about slight enlargement of the liver, and caused induction of the enzyme activities. On daily treatment with CP, the body weights went back their initial whights by seven days, and the activities in liver homogenates were restored to almost the same level as those of controls or slightly higher. Weights of the liver and brain did not change. The enzyme activities of the brain were neglisibly low and showed no change either by treatment with CP or phenobarbital. These data may suggest the possibility that when CP is medicated in patients, its plasma level might increase initially and then decrease gradually during medication, following the changes of its metabolizing enzyme activities. 相似文献
638.
S. NAKAGAWA M. ASAKA M. KATO T. NAKAMURA C. KATO T. FUJIOKA M. TATSUTA K. KEIDA S. TERAO S. TAKAHASHI N. UEMURA T. KATO N. AOYAMA D. SAITO M. SUZUKI A. IMAMURA K. SATO H. MIWA H. NOMURA M. KAISE S. OOHARA T. KAWAI K. URABE N. SAKAKI S. ITO Y. NODA A. YANAKA K. KUSUGAMI H. GOTO T. FURUTA M. FUJINO F. KINJYOU & T. OOKUSA 《Alimentary Pharmacology & Therapeutics Symposium Series》2006,2(1):214-218
639.
640.
K. TAKAHASHI O. INANAMI M. KUWABARA 《International journal of radiation biology》2013,89(9):1099-1105
Purpose: To examine the roles of intracellular calciumin radiation-induced apoptosis of MOLT-4 cells, the effects of intracellular calcium chelator BAPTA-AM on the induction of apoptosis and the activation of apoptosis-relating enzymes SAPK/JNK and caspase-3 were studied. Materials and methods: MOLT-4 cells pretreated with 5 mum BAPTA-AM were exposed to X-rays. DNA fragmentation, the expression of phosphorylated SAPK/JNK and the activation of caspase-3 and calcium concentration were measured by agarose gel electrophoresis, Western blotting and spectrofluorometry. Results: Time-dependent ladder-like DNA fragmentation was observed at 4h, 5h and 6h after exposure to 15Gy of X-rays. This fragmentation was significantly attenuated by pretreatment with BAPTA-AM up to 5h after irradiation, but the attenuation due to BAPTA-AM was no longer detectable at 6h. Activation of SAPK/JNK and caspase-3 was observed at 1 and 4h after X-irradiation, respectively, and BAPTA-AM retarded the activation for 2h. The pretreatment with BAPTA-AM was found to suppress the increase of calcium concentration for 6h after irradiation. Conclusion: These results revealed that chelation of calcium merely delayed the onset of the radiation-induced apoptosis regulated by the activation of SAPK/JNK and caspase-3, and calcium was not essential for the induction of apoptosis in X-irradiated MOLT-4 cells. 相似文献