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31.
An attempt was made to detect a pancreatic tumor antigen (PTA) in transplantable pancreatic adenocarcinomas induced by N-bis(2-hydroxypropyl)nitrosamine (DHPN) in hamsters. Antibody against antigenic protein was raised by immunizing rabbits with whole homogenate of the tumors transplanted into the back of hamsters. PTA was purified by affinity chromatography and shown to have the physicochemical properties of a glycoprotein with a molecular weight of 800,000, migrating in the beta regions upon agarose gel electrophoresis. Loss of immunological properties was observed after heating at 65 degrees C for 30 min. Enzyme immunoassay revealed that the levels of PTA in the serum and tissue showed a positive correlation with the induction of the presence of tumor, and size of the tumor. It is tentatively suggested that PTA values above 150 ng/ml serum are indicators of tumors, because in normal hamsters the PTA range is from 25 to 130 ng/ml serum. Immunohistochemically, PTA was demonstrated to be localized within the cytoplasm of epithelial tumor cells of well-differentiated tubular adenocarcinomas. 相似文献
32.
Yamaji Yasuyoshi; Nakazato Yuichi; Oshima Naoki; Hayashi Matsuhiko; Saruta Takao 《Nephrology, dialysis, transplantation》2004,19(10):2592-2597
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients. 相似文献
33.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension. 相似文献
34.
Keiichiro Wada Yumiko Motoi Yasuko Komatsuzaki Masashi Takanashi Hideo Mori Takao Urabe Yoshikuni Mizuno 《Brain and nerve》2006,58(1):79-90
We report an 81-year-old patient with progressive dementia, disinhibition, and gait disturbance. He showed visuospacial disorientation, apathy, and gait disturbance at 76 years of age. When he was 77 years old, he was diagnosed Parkinson's disease and treated with the 1-dopa, the dopamine agonist, the amantadin, and the anti-cholinergic drug. These treatments didn't improve his motor disturbances. His motor disturbances, apathy, and abnormal behavior progressed gradually. He was admitted to the hospital at the age of 77. He was severely demented and akinetic. Sometime, violent behavior and hallucination were seen. The brain MRI showed frontotemporal lobe atrophy and severe leukoaraiosis of the frontal white matter. At 79 years of age, he became mute and bedridden. When he was 80 years old, large infarction occurred in his occipital lobe. He died due to renal failure and respiratory suppression at 81 years of age. His brain was examined pathologically. At the neurological CPC, the chief discussant arrived at the conclusion that his diagnosis was Binswanger's disease. Other possibilities discussed were FTD, CBD, and progressive subcortical gliosis. The post-mortem examination revealed diffuse white matter degeneration due to atherosclerotic change of the small artery, many lacunar infarctions, and severe infarction of the occipital lobe. These findings led the diagnosis of Binswanger's disease and cerebral infarction. 相似文献
35.
36.
Koibuchi Yukio; Iino Yuichi; Joshita Takashi; Yokoe Takao; Shinkai Hiroko; Kawashima Kenji; Kobayash Junya; Tanaka Sunao; Oyama Tetsunari; Hikino Toshiaki; Morishita Yasuo 《Japanese journal of clinical oncology》1995,25(6):273-277
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments. 相似文献
37.
Katsunobu Kawahara Shinji Akamine Takao Takahashi Akihiro Nakamura Hiroyuki Kusano Tohru Nakagoe Takayuki Nakazaki Hiroyoshi Ayabe Masao Tomita 《Surgery today》1994,24(12):1101-1103
We report herein the case of a 75-year-old man who developed anal canal metastasis from squamous cell carcinoma of the lung. Initially, he underwent a right middle and lower lobectomy combined with left atrial wall resection under cardiopulmonary bypass. He presented 3 months later with an anal polyp which had prolapsed and bled, for which he underwent a transanal polypectomy. Histologically, the polyp was classified as squamous cell carcinoma and considered to be a metastasis from the primary lung cancer. He is presently well with no signs of recurrence 9 months after his initial operation. To our knowledge, there has been no other case of anal metastasis from lung cancer ever reported. 相似文献
38.
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40.
A case-control study of breast cancer among Japanese women: with special reference to family history and reproductive and dietary factors 总被引:8,自引:0,他引:8
Dr. Ikuko Kato Dr. Shigeto Miura Fijio Kasumi Takuji Iwase Hideya Tashiro Yoshihiro Fujita Hiroki Koyama Tadashi Ikeda Kiyoshi Fujiwara Keiichi Saotome Kazuaki Asaishi Rikiya Abe Mitsuhiro Nihei Tsunehiro Ishida Takao Yokoe Hiroshi Yamamoto Motoi Murata 《Breast cancer research and treatment》1992,24(1):51-59
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer. 相似文献