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11.
We investigated the effects of energy restriction on the pituitary-ovarian axis and on a hormone responsive gene, the mouse mammary tumor virus (MMTV). Female C3H/SHN F1-hybrid mice, known to display a high incidence of mammary tumors, ate an energy-restricted diet (48 kcal/wk) or a control diet (95 kcal/wk) beginning at the time of weaning. By 67 wk of age, 12 of 32 mice in the control group, but none of the 33 mice in the energy-restricted group, had developed mammary tumors. Six tumor-free mice from each group were studied in detail at 67 wk of age. All six tumor-free control mice, but none of the six energy-restricted mice, showed uterine endometrial hyperplasia at autopsy. Mice subjected to energy restriction did not display an estrous cycle. The average levels of MMTV mRNA in mammary glands and uteri were strongly reduced by energy restriction. MMTV mRNA levels in mammary glands from control mice were two orders of magnitude lower than those in mammary tumors. Energy restriction lowered the percentage of pituitary mammatropes and suppressed proliferation of mammatropes with advancing age. Energy restriction thus appeared to inhibit endometrial hyperplasia and to decrease MMTV production at the mRNA level in the mammary glands and in the uterus. These effects may be a consequence of hormonal changes originating at the pituitary-ovarian axis. 相似文献
12.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
13.
Kazumasa Miyake Atsushi Tatsuguchi Mikiko Tachibana Masanobu Kusunoki Yoko Shinji Kei Shinoki Tetsuro Hiratsuka Kazuhiro Nagata Hitoshi Nishigaki Seiji Futagami Ken Wada Taku Tsukui Toshiro Yoshiyuki Akira Tokunaga Takashi Tajiri Choitsu Sakamoto 《Digestive endoscopy》2004,16(2):172-175
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia. 相似文献
14.
15.
S Wada R Yasumoto T Kishimoto M Maekawa M Harima S Nishio 《Hinyokika kiyo. Acta urologica Japonica》1991,37(11):1441-1445
Transrectal hyperthermia was performed on 30 patients with benign prostatic hyperplasia twice a week for a total of ten times with the temperature of the prostatic tissue set at 43.0 degrees C. In our in vitro experiment using an agar phantom, the highest temperature was observed at approx. 1.5 cm from the point where the 915-MHz microwave was generated. Our histopathological study of the prostatic tissue, resected at open surgery after three days of hyperthermia, indicated that the effect of hyperthermia first occurred in the interstitial tissues, and then extended to the epithelial cells. Subjective symptoms and objective findings were evaluated. In almost all cases, improvement was observed in subjective symptoms after completion of the treatment. The residual urine volume improved significantly. Also, significant improvement was observed in our urodynamics study. In 16 out of 30 cases (53%), both subjective symptoms and objective findings were still improved after six months. 相似文献
16.
Yasuhisa Fujibayashi Hideyuki Taniuchi Kouichi Wada Yoshiharu Yonekura Junji Konishi Akira Yokoyama 《Annals of nuclear medicine》1995,9(1):1-5
The reductive retention of62Cu-PTSM was comparatively studied in the brain and Ehrlich ascites tumor cells by electron spin resonance spectrometry and nonradioactive Cu-PTSM. In the brain, only the mitochondrial fraction showed the ability to reduce Cu-PTSM, and the other subcellular fractions did not. In contrast, the cytosolic fraction of Ehrlich ascites tumor cells was the specific site of Cu-PTSM reduction. It was therefore considered that the retention of Cu-PTSM in the brain is closely related to mitochondrial reduction, most probably involving the mitochondrial electron transport system. 相似文献
17.
18.
S Isaka T Okano J Shimazaki S Murakami T Hara S Kataumi T Yoshida T Nagayama T Wada Y Kitamura 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1992,83(10):1662-1667
Many reports about the increase of renal cell carcinoma patients have been published in Japan recently, however, the real fluctuations in the total number of patients in relation to the change of population have not been reported yet. Most of the patients with renal cell carcinoma in the last 10 years were examined in Chiba prefecture, which has a population of about five million and 25 active urological offices. Histologically confirmed cases were investigated by sending questionnaire letters. The items were as follows; sex, age, address, occupation, family history, past history, symptoms, examination methods that first detected the tumor, operation date, tumor diameter and clinical stage. Twenty two offices returned answers and 560 cases who lived in Chiba were found to have renal cell carcinoma from 1980 to 1989. Yearly incidence rates per 100,000 persons demonstrated a significant increase from 0.32 to 2.07. Small, asymptomatic and low stage cancers have been increasing rapidly, however, the rate of metastatic disease has not shown any decrease. The main cause of rapid increase seems to be attributed to progress in diagnostic methods and increase of early detection, but the possibility of an increase in some carcinogenic factors can not be ruled out. 相似文献
19.
Katsunobu Kawahara Takeshi Shiraishi Kan Okabayashi Akinori Iwasaki Yasuteru Yoshinaga Kouji Hayashi Jyunichi Yamashita Takayuki Shirakusa 《Surgery today》1997,27(2):163-165
A patient with a recurrent tumor in the trachea adjacent to the right main bronchus was treated by surgical resection 19 months
after undergoing surgery for the primary cancer. The patient had previously undergone right upper lobectomy for T1N0M0 stage
I squamous cell carcinoma. A carinal resection was performed which included 4 rings of the trachea, 2 rings of the righ main
bronchus, and 1 ring of the left main bronchus. Reconstruction consisted of an end-to-end anastomosis of the trachea and left
main bronchus, and an end-to-side anastomosis of the right and left main bronchi. The postoperative course was uneventful,
and at present the patient is healthy 12 months following reoperation. 相似文献
20.