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41.
We investigated the interactions in the KOC-2s human ovarian cancer cells on the effect of glucocorticoids, and sex steroid hormones in ovarian carcinomas. At 10(-8) M to 10(-5) M, dexamethasone (Dex) decreased the number of cells by 75-80% (p<0.001). At 10(-8) M and 10(-7) M, hydrocortisone (HC) decreased the number by 50% (p<0.01); at 10(-6) M and 10(-5) M, the decrease in number of cells was 65%. The E-2 decrease in number was not statistically significant. Progesterone (PG) showed at 10(-8) to 10(-6) M an increase in number of cells, however, at 10(-5) M it was decreased by 70% with a significant difference (p<0.001). Dex (10(-8)-10(-5) M), HC (10(-8)-10(-5) M) and PG (10(-5) M) produced internucleosomal cleavage of DNA into fragments with multiples of 180 to 200 bp. The TNF-alpha with addition of Dex (10(-8)-10(-5) M) and HC (10(-8)-10(-5) M) was increased after 24 h, 48 h (p<0.001); however, gradually decrease after 72 h. When PG (10(-8)-10(-5) M) was added, PG (10(-5) M) increased the secretion of TNF-alpha after 72 h. Our findings demonstrate that glucocorticoids, and PG directly induce apoptotic DNA fragmentation of KOC-2s cells. However, the secretion of TNF-alpha and expression of Fas antigen were totally different in these substances. These data provide a basis for future studies on the mechanisms of apoptotic effect of glucocorticoids, and PG and the therapeutic effects of these substances. 相似文献
42.
In order to elucidate the cause of body weight loss in the early stage of tumor progression, morphological changes of striated muscle were investigated in rabbits every 10 days after VX2 carcinoma implantation. The lean body mass started to decrease in the tumor-bearing rabbits 10 days after implantation, and body fat ratio showed a significant decrease from 30 days, different from the starved rabbits, whose lean body mass and body fat ratio started to decrease from 10 days. Morphological hallmarks of apoptosis in muscle cells were detected in tumor-bearing animals prior to the tumor growth but not in starved animals. These findings suggest that muscle cell apoptosis may be responsible for the body weight loss in the early tumor-bearing. 相似文献
43.
Shigematsu Y Korogi Y Hirai T Okuda T Sugahara T Liang L Takahashi M 《Journal of magnetic resonance imaging : JMRI》1999,10(6):939-944
This work investigated whether turbo magnetic resonance angiography (MRA) can replace conventional MRA in screening examination of intracranial arteries. A phantom was used to evaluate the effect of the zero-filling interpolation (ZFI) technique on spatial resolution and partial volume effect. Thirty-one consecutive patients underwent both turbo MRA with a slice thickness of 0.7 mm (data were measured as 1.33 mm sections) and conventional MRA with 1.0 mm sections. In the phantom studies, ZFI did not improve the spatial resolution, but the partial volume effect was somewhat reduced. In the clinical evaluation, turbo MRA showed better signal-to-noise and contrast-to-noise ratios of the intracranial major vessels than conventional MRA. The lesions included cerebral aneurysms less than 3 mm in diameter, occlusive vascular disease, arteriovenous malformations, and arteriovenous fistulas. These were all depicted on both turbo MRA and conventional MRA. Turbo MRA is a useful screening procedure because of its capability of delineating lesions in approximately half the usual imaging time. J. Magn. Reson. Imaging 1999;10:939-944. 相似文献
44.
Finger bougie method compared with pyloroplasty in the gastric replacement of the esophagus 总被引:2,自引:0,他引:2
Yamashita Y Hirai T Mukaida H Yoshimoto A Kuwahara M Inoue H Toge T 《Surgery today》1999,29(2):107-110
To elucidate the necessity of pyloroplasty for the gastric tube through the posterior mediastinum in esophageal surgery, gastric
emptying and duodenogastric reflux (DGR) were evaluated in 16 cases undergoing an anterior pylorectomy (group P) and in 16
cases treated by the finger bougie method (group F). First, the obstruction and reflux symptoms were examined based on a patient
questionnaire using a brief scoring system. The median value of the symptom score showed the patients in P to have more symptoms
than those in F; however, the difference was not significant (8.0 vs 6.0). Secondly, the swallowed Tc O4
− (85 MBq) was counted using a gamma camera at three sites on the sternal bone in the upright position based on a gastric transit
scintigram. Both the descending time of the RI peak and the clearance rates were similar between the two groups. Thirdly,
intragastric 24-h pH monitoring was carried out. Antimony pH sensors were anchored 5 and 15 cm below the esophagogastrostomy.
We could not find any difference between the two groups in both the % time pH>4 and %time pH>7. These findings thus revealed
no big difference between groups P and F. The finger bougie method to drain the vagotomized posterior mediastinal stomach
was found to achieve results similar to conventional pyloroplasty, while it was also simpler and safer. 相似文献
45.
A 45-year-old male was admitted to our hospital for investigation of a nodular shadow in segment 5 of the right lung on a
chest computed tomogram. A right middle lobectomy with mediastinal lymph node dissection was performed under a diagnosis of
lung cancer, and histologic examination confirmed small cell carcinoma. There were sarcoid reactions in the resected lymph
nodes and the lung parenchyma, but no signs of systemic sarcoidosis were evident. Sarcoid reactions are rarely observed in
the regional lymph nodes draining malignant tumors. Moreover, while they are most common in squamous cell carcinoma of the
lung, they extremely rare in small cell carcinoma. To our knowledge, this is only the third report of this unusual entity
in the English and Japanese literature. 相似文献
46.
A recent report has demonstrated that inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ release plays a crucial role in neurite growth. Here, using 31P-NMR, we examine whether activation of the metabotropic glutamate receptor 1 (mGluR1), which induces the production of IP3, could modulate phospholipid metabolism in human embryonic kidney 293 cells. mGluR1alpha- but not ionotropic glutamate receptor 1-expressing cells stimulated with glutamate exhibited a drastic reduction in the phosphorylcholine level, with corresponding increases in the level of phosphatidylcholine, a major phospholipid component. Quantitative analysis of cell growth revealed that mGluR1alpha-expressing cells cultured with 100microM glutamate were statistically significantly longer than the nontransfected cells. The effect was no longer observed following coincubation with a metabotropic glutamate receptor antagonist, (RS)-alpha-methyl-4-carboxyphenylglycine. These results suggest that mGluR1alpha activation triggers phosphatidylcholine biosynthesis and may contribute to neurite extension. 相似文献
47.
Comparison of low attenuation areas on computed tomographic scans between inner and outer segments of the lung in patients with chronic obstructive pulmonary disease: incidence and contribution to lung function 总被引:5,自引:1,他引:4 下载免费PDF全文
BACKGROUND: The low attenuation areas on computed tomographic (CT) scans have been reported to represent emphysematous changes of the lung. However, the regional distribution of emphysema between the inner and outer segments of the lung has not been adequately studied. In this study the regional distribution of low attenuation areas has been compared by quantitative CT analysis and the contribution of the regional distribution to pulmonary function tests evaluated in patients with chronic obstructive pulmonary disease (COPD). METHODS: Chest CT images and the results of pulmonary function tests were obtained from 73 patients with COPD. The lung images were divided into inner and outer segments in the upper (cranial), middle, and lower (caudal) sections. The percentage ratio of low attenuation area to corresponding lung area (LAA%) was then calculated. The LAA% of each segment was also compared with the results of pulmonary function tests. RESULTS: The mean (SD) LAA% of the inner segment was 39.1 (18.5) compared with 28.1 (13.2) for the outer segment (p<0.0001). Linear and multiple regression analyses revealed that airflow limitation is closely correlated with the inner segment LAA% of the lower lung. In contrast, the carbon monoxide transfer factor is closely correlated with the inner segment LAA% of the upper lung. CONCLUSION: Low attenuation areas on CT scans are more often found in the inner segment of the lung than in the outer segment, and the contribution of the inner segment to pulmonary function tests may be greater than the outer segment. 相似文献
48.
Y Hirai K Nishide K Yamauchi I Fujimoto K Hasumi K Masubuchi H E Dytch 《The Journal of reproductive medicine》1992,37(3):267-272
To analyze the healing process after laser therapy for cervical lesions, the clinical, cytologic, histologic and colposcopic features in 109 cases were studied chronologically. The healing process of the cervical epithelium usually began from both the squamous and columnar epithelial borders, starting around the 10th day after laser therapy; the process covered the whole tissue defect with multilayered epithelium within seven weeks. Inflammatory changes also usually abated within that time. Cytomorphologically, laser therapy resulted in the occurrence of (mostly degenerated) "fiber-type" and orangeophilic cells in smears taken during the first two weeks after treatment. Tissue repair cells were seen in smears collected from the first posttherapy day through the fourth week after laser therapy. Using computer-assisted image cytometry, the reparative cells in samples taken shortly after treatment (roughly, the first to fifth days) exhibited more hyperchromatic (3-4N) nuclei than did those in later samples; however, the mean DNA content of the early reparative cells was generally concentrated around that of the 2N reference cells. These findings suggest that follow-up, including cytologic and colposcopic examination, for the early detection of residual or recurrent lesions should start in the eighth week and continue periodically for at least one year. 相似文献
49.
M Hirai 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1992,83(5):597-604
The effect of local hyperthermia on the prostate using 13.56 MHz radio frequency wave (RF wave) was reported. Firstly, temperature and blood flow of the prostate in normal dogs were measured during local hyperthermia. In most part of the prostate, the temperature reached over 42 degrees C, which was considered as favorable for the hyperthermia therapy. Blood flow of the prostatic tissue rose more slowly than that of muscle tissue. Secondly, the tissue concentration of anticancer agents after local hyperthermia was measured. There was a tendency that drug concentration in the prostate tissue after local hyperthermia was higher than that without local hyperthermia. Histological findings showed interstitial edema and congestion. As a clinical trial, 14 cases of prostatic cancer were treated with local hyperthermia after the administration of anticancer agents. Seven of them were fresh cases and the others were relapsed cases. After treatment, tumor size was reduced in 13 cases. According to "The Response Criteria for Urologic Tumor", one Complete Response, 3 Partial Response and 10 No Change cases were obtained. There was no tumor progression. As for side effects, bone marrow suppression, loss of appetite, diarrhea and skin burns were noted. However, these side effects were mild, and did not interrupt the treatment. Local hyperthermia of the prostate after systemic chemotherapy could be carried out safely and effectively in patients with prostatic cancer. 相似文献
50.
Nonradioactive 31P-NMR spectroscopy has previously been used for the study of protein phosphorylations. However, the procedures does not seem to be easy for non-experts of this field, hence, this approach has not been widely used. We introduce here a simple protocol with 31P-NMR spectroscopy to study in vitro phosphorylation in receptor proteins. The effectiveness of this method was verified using synthetic peptides and recombinant proteins of the C-terminus of the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor, whose phosphorylations are considered to have important roles in synaptic plasticity. We show that a decrease in the pH of the sample solution after the phosphorylation reaction is critical for the separation of the phosphorylation signals. In the analysis of the C-terminal portion of the GluR2 AMPA receptor, the phosphorylation sites of which had not hitherto been well clarified, we found the presence of at least three protein kinase C (PKC) phosphorylation sites. Furthermore, this method allows prediction of the origins of each of the phosphorylation peaks. Thus, the techniques we described here is useful for examination of protein phosphorylation and permits us to safely conduct repetitive experiments. 相似文献