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21.
Mechanism of atrial natriuretic polypeptide and sodium nitroprusside-induced relaxation in guinea-pig tracheal smooth muscle 总被引:3,自引:0,他引:3
Atrial natriuretic polypeptide (ANP) is composed of a family of peptides isolated from rat and human atria. In the present study, the relaxant effects of ANP, sodium nitroprusside and 8-bromo-cyclic guanosine monophosphate (GMP) were investigated in guinea-pig tracheal smooth muscle, and the tissue cyclic GMP and cyclic adenosine monophosphate (AMP) concentrations were measured. ANP, sodium nitroprusside and 8-bromo-cyclic GMP showed relaxant effects on the spontaneous tone in normal Krebs solution (5.9 mmol/l K(+)-2.4 mmol/l Ca++ solution). They diminished relaxant effects on 40 mmol/l K(+)-0.1 mmol/l Ca++ induced contraction, which was approximately the same tension as the spontaneous tone. Sodium nitroprusside and 8-bromo-cyclic GMP diminished less relaxant effects on 40 mmol/l K(+)-2.4 mmol/l Ca++ induced contraction, but ANP showed no relaxation. The tissue cyclic GMP levels following administration of ANP and sodium nitroprusside in normal Krebs solution, in 40 mmol/l K(+)-2.4 mmol/l Ca++ solution, and in 40 mmol/l K(+)-0.1 mmol/l Ca++ solution increased dose-dependently without regard to external Ca++ concentrations, while the tissue cyclic AMP levels did not change. These results suggest that ANP might be a novel potent relaxant in airway smooth muscle and the relaxant effect may be, at least in part, mediated by cyclic GMP. There was a difference in relaxant effects on tracheal smooth muscle between ANP and sodium nitroprusside. 相似文献
22.
The effect of reflux of the duodenal contents on the development of gastric stump carcinoma without carcinogen in rats was studied. At the first experiment, seventy male Wistar rats were subjected to gastrojejunostomy for the diversion of duodenal contents into the resected stomach through the afferent and the efferent loops. The incidence of adenocarcinoma in the afferent anastomosis were 0/8 (0%) at the 10th week, 3/16 (18.8%) at the 20th week and 7/20 (35%) at the 40th week, so the incidence was apt to rise in parallel to the time. In the second experiment, ninety rats were divided into 4 groups: Group I received the same operation as the first experiment, group II received the operation with Braun's anastomosis, group III received the operation for reflux of bile alone to the remnant stomach, and group IV received the operation for reflux of pancreatic juice alone. Animals surviving after surgery were sacrificed at the 40th week. The incidence were 33.3% in group I, 0% in group II, 0% in group III, and 8.3% in group IV, respectively. These findings suggest that reflux of duodenal contents (both bile and pancreatic juice) is an important factor in the gastric stump carcinogenesis. 相似文献
23.
Statistical evaluation of determinants of progression of superficial bladder cancer by proportional hazards model 总被引:2,自引:0,他引:2
M Takashi T Sakata T Murase Y Takagi T Nagai M Sahashi T Shimoji K Miyake N Hamajima 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(1):116-121
To evaluate clinical and pathological factors present at the initial consultation which affect disease progression, we reviewed data from 223 patients with superficial bladder cancer (pTa and pT1) who were initially treated at Nagoya University Hospital between January 1973 and December 1987. The factors included in the present analysis were age, sex, symptoms, interval between initial symptoms and first consultation, location of tumor, size, number, endoscopic shape, histological pattern of growth, grade and stage. The median duration of the follow-up after initial treatment was 46 months. Of the 223 patients, 17 died: 8 (3.6%) of bladder cancer and the remaining 9 (4.0%) of unrelated causes. Disease progression developed in 12 patients (5.4%): muscle invasion of the bladder wall in 11 and lung metastasis in one. The interval between initial treatment and progression ranged from 4 to 108 months, with a median of 11.5 months. Of the 12 patients, 9 (75%) had disease progression within 2 years. Progression was significantly associated with poor prognosis (p less than 0.001): the 5-year actuarial survival rates were 47.1% and 92.8% in patients with and without progression, respectively. Univariate analysis by Cox's proportional hazards model demonstrated that characteristics such as irritative bladder symptoms, higher-grade tumors, invasion into lamina propria, and nonpapillary growth seen at initial consultation were significantly related to disease progression. Cox's proportional hazards model produced hazard ratios of 10.2 in irritative bladder symptoms (yes vs. no), 6.3 in histological grade (grade 3 vs. grades 0-2), 4.9 in stage (pT1 vs. pTa), and 4.7 in pattern of growth (papillary vs. nonpapillary).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
24.
Shigeki Ohgitani Akimitsu Miyauchi Yasuyuki Takagi Yoshio Fujii Takuo Fujita Misa Nakamura Zhi-qiang Zhang Liang Shan Mitsuyo Sasaki Ryuichi Tsukino Toyoharu Yokoi Kennichi Kakudo Tomitaka Nakayama Junya Toguchida Hiroshi Kanoe Shinichi Aizawa Masao S. Sasaki Takashi Nakamura M. Suda K. Tanaka Y. Ogawa N. Tamura A. Yasoda H. Itoh M. Uehira N. Nishimoto T. Takigawa K. Shiota K. Nakao 《Journal of bone and mineral metabolism》1997,15(3):165-171
25.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
26.
J Nagata M Yamauchi K Terabe T Watanabe H Ichihara H Takagi N Nakashima 《Nihon Geka Gakkai zasshi》1987,88(4):489-492
Surgical experience of a rare case of malignant retroperitoneal cyst is reported. A 41-year-old female was admitted on Feb. 26, 1986, complaining of left lower abdominal tumor and mild abdominal pain. She underwent complete removal of an abdominal tumor located at the left flank lateral to the sigmoid colon on March 5. The tumor was well encapsulated, cystic and oval, 12 X 10 X 9 cm in size. Histologic feature of the tumor is classified as mucinous cystadenoma of low grade malignancy by WHO classification. 相似文献
27.
T Takagi T Yamaguchi T Mizoguchi T Amemiya 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1989,199(2-3):123-126
Metastasis directly to the optic nerve head without choroidal involvement is rare. We report a case of metastatic adenocarcinoma of the optic nerve head and retina with vitreous seeds which was observed in a 45-year-old Japanese male. The primary site of the lesion was clinically the upper lobe of the left lung. Tumor emboli were observed in the central retinal vein. Vitreous seeds appeared to have arisen from a necrotic area and papillary projections of the tumor. 相似文献
28.
A case of a bilateral pulmonary hernia of the lungs into the supraclavicular fossae is described. A man, aged 79, with severe chronic asthma and chronic bronchitis due to air pollution, complained of a cervical mass off and on for several years. The herniation was greater on the right side. It could be identified on physical examination by the presence of a soft painless supraclavicular bulge which was exaggerated by strain or cough. Radiologically this herniation could best be identified on lateral cervical roentgenogram. It is said that cervical lung hernia is a rare condition, but in our experience supraclavicular herniation of the lung is not unusual in cases of severe chronic obstructive lung disease. 相似文献
29.
Improvement of oxygen metabolic reserve after extracranial-intracranial bypass surgery in patients with severe haemodynamic insufficiency 总被引:8,自引:0,他引:8
Summary The effectiveness of extracranial-intracranial arterial bypass (EC-IC bypass) surgery on impaired haemodynamic status was studied in 12 patients with reduced regional cerebral perfusion pressure (rCPP) and elevated regional oxygen extraction fraction (rOEF) in the area distal to the symptomatic arterial lesion. Postoperative positron emission tomography (PET) study demonstrated a statistically significant decrease of rOEF in the operated hemispheres with disappearance of the pre-operative interhemispheric rOEF difference. Regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were also increased in the operated hemispheres with disappearance of the pre-operative interhemispheric differences. Regional CBF/regional cerebral blood volume (rCBV) ratios of the symptomatic hemispheres were increased after surgery, but were still lower than in the contralateral hemispheres. We conclude that EC-IC bypass surgery improves impaired cerebral oxygen metabolic reserve. 相似文献
30.