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The effect of circumstances and/or organs on the grade of cancer growth and malignancy was studied, using hereditarily identical VX2 cancer. VX2 cancer cells, 10(6) cells/0.1 approximately 0.2 ml, were injected into the liver, portal vein, stomach- and colon-walls of Japanese white rabbits. Each of the experimental groups consisted of 14, 12, 19 and 24 animals, and 3 or 4 animals of each groups were sacrificed 7, 14, 21 and 28 days after the implantation. All the animals of portal vein and liver groups died of cancer within 3 and 4 weeks respectively. However, all the animals of stomach and colon groups survived during 4 weeks. Although cancer volume doubling time was not calculated in portal group because of the multiple and diffuse tumor-formation, the time was 2.6 days in liver, 4.3 days in colon and 5.9 days in stomach groups in which a single tumor developed. Lymphatic and/or hematogenous metastases were found at the same time after the implantation as vascular invasion occurred. Metastases were confirmed in 100% in liver group and 40% in portal group 2 weeks after the implantation, and 80% and 50% in colon and stomach groups respectively 4 weeks after the implantation. The results suggested that hereditarily identical VX2 cancer was variable in the different organs and circumstances, and that the growing circumstances strongly affected the cancer malignancy. It was also suggested that the malignancy was correlated with the growth rate and the time of metastasis of cancer. 相似文献
54.
Yoshikiyo Akasaka MD PhD ; Kinji Ito PhD ; Kazuko Fujita PhD ; Kazuo Komiyama DDS ; Ichiro Ono MD PhD ; Yukio Ishikawa MD PhD ; Yuri Akishima MD PhD ; Hiroko Sato MD PhD ; Toshiharu Ishii MD PhD 《Wound repair and regeneration》2005,13(4):373-382
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo. 相似文献
55.
Hiroyuki Sakai Masaki Ibe Hidetoshi Takahashi Shinobu Matsuo Kensaku Okamoto Isao Makino Yukio Oomori Hajime Iizuka 《The Journal of dermatology》1996,23(1):42-46
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion. 相似文献
56.
Toshihisa Inoue MD Shigeru Watanabe MD Yoshiaki Masuda MD Katsuya Yoshida MD Hitoshi Imai MD Yasuo Imazeki MD Yoshiaki Ishizuya MD Masashi Koga MD Hirotoshi Kato MD Hiroo Ikehira MD Yukio Tateno MD 《Clinical imaging》1996,20(4):262-268
The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition. 相似文献
57.
Yoko Kubota Teruhiro Nakada Kyoichi Imai Hidetoshi Yamanaka Hideki Sakai Yutaka Saito Yukio Tomaru Koichi Kitamura Osamu Sugano Isoji Sasagawa 《The Prostate》1995,26(1):50-54
There have only been a few studies of chemo-endocrine therapy compared with endocrine therapy alone in newly diagnosed prostate cancer patients. We assessed the effects of these two therapies by comparing long-term survival rates. One hundred and twenty-nine patients were entered in this study between November 1977 and March 1992. Seventy-seven patients were treated with endocrine therapy alone. Other 52 patients received chemo-endocrine therapy, which included orchiectomy and/or diethylstilbestrol diphosphate (DES-DP) plus Cisplatin, with or without other cytotoxic agents. All patients had bone metastasis at the beginning of the study. There was a significant difference in survival between patients who received endocrine therapy and chemo-endocrine therapy (P = 0.0078). That is, survival rate was superior for the chemoendocrine therapy patients throughout the entire follow-up period. These data suggest that early chemo-endocrine therapy containing Cisplatin, with or without maintenance chemotherapy, is a potentially effective treatment for newly diagnosed metastatic prostate cancer and is worth further investigation via a randomized trial. 相似文献
58.
Michiko Kawaguchi Masaaki Techigawara Takako Ishihata Tsukasa Asakura Fujiko Saito Kazuhira Maehara Yukio Maruyama 《Heart and vessels》1997,12(6):267-274
Summary The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological
changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial
changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural
changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls
without hypertension or diabetes mellitus (n=6), and patient with hypertension (n=3), diabetes mellitus (n=8), and diabetes with hypertension (n=8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures
were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials
showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement
membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater
in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in
the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective
of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial
cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells
and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately,
to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension. 相似文献
59.
Tadashi Nakazawa Yoshiyuki Takami Robert Benkowski Satoshi Ohtsubo Ohashi Yukio Eiki Tayama Goro Ohtsuka Yoshinari Niimi Julie Glueck Akinori Sueoka Helmut Schmallegger Heinrich Schima Ernst Wolner Yukihiko Nosé 《Artificial organs》1997,21(7):597-601
Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device. 相似文献
60.
Shimeru Kamihira Shigehiro Nakashima Shin Saitoh Michiko Kawamoto Yumiko Kawashima Mitoshi Shimamoto 《Cancer science》1993,84(8):834-837
A fully automated chemiluminescence immunoassay was developed for the detection of antibodies to HTLV-I. We used partially purified viral antigens coated on small polystyrene beads together with acridinium ester-labeled anti-human immunoglobulin G mouse immunoglobulin G in this method. A good agreement was observed between our proposed method, the indirect immunofluorescence assay, the particle-agglutination test and the enzyme immunoassay. This new method, which is simple, sensitive, specific and rapid, should be useful for mass screening of anti-HTLV-I antibodies. 相似文献