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1.
Kazunori Aizawa Takeshi Hanaoka Hiroki Kasai Kaoru Kogashi Setsuo Kumazaki Jun Koyama Hiroshi Tsutsui Yoshikazu Yazaki Noboru Watanabe Osamu Kinoshita Uichi Ikeda 《Hypertension research》2006,29(2):123-128
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH. 相似文献
2.
Comparison of characteristics of esophageal squamous cell carcinoma associated with head and neck cancer and those with gastric cancer 总被引:3,自引:0,他引:3
H Kuwano M Morita S Tsutsui Y Kido M Mori K Sugimachi 《Journal of surgical oncology》1991,46(2):107-109
In ongoing reviews of 339 patients with surgically treated primary squamous cell carcinoma, there were 19 (5.6%) with concurrent gastric cancer and 11 (3.2%) with head and neck cancer. The incidences of intra-esophageal multiple occurrence of esophageal cancer are 27.3% and 26.3% in those with associated head and neck cancer and gastric cancer, respectively, and higher than 7.1% in those without such a concurrent cancer. There was no difference in the clinicopathological characteristics of those with concurrent head and neck and gastric cancers, except for the higher incidence of metachronous occurrence in the former. These findings suggest that, in cases of esophageal cancer associated with concurrent head and neck cancer and gastric cancer, intraesophageal multiplicity of the esophageal carcinoma is frequent and that preoperative serial evaluations is most important to design treatment and estimate the prognosis. 相似文献
3.
Novel SCN5A mutation (Q55X) associated with age-dependent expression of Brugada syndrome presenting as neurally mediated syncope. 总被引:1,自引:0,他引:1
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism. 相似文献
4.
Design of a Centrifugal Blood Pump with Magnetic Suspension 总被引:1,自引:0,他引:1
Takashi Yamane Tadashige Ikeda Toyoki Orita Tatsuo Tsutsui Tomoaki Jikuya 《Artificial organs》1995,19(7):625-630
Abstract: A new concept blood pump, whose impeller is suspended by permanent magnets and a mechanical pivot without seals or ball bearings, is presented in this paper. The primary aim of the blood pump is an application to implantable artificial hearts. The prototype model is of a centrifugal type with a four-vaned semiopen impeller 50 mm in diameter. Since this mechanism has no seals or ball bearings, flow stagnation or heat generation that might cause blood cell denaturation is expected to be small. The results of performance testing for the prototype model 2 were satisfactory regarding pump head and efficiency. The radial-suspension magnets and the magnetic coupling were stable. As a result, the present mechanism has been verified to be a candidate applicable to implantable artificial hearts. 相似文献
5.
A review of data on 360 patients with esophageal squamous cell carcinoma who underwent esophageal resection revealed 14 cases (3.9%) and 16 lesions with synchronous gastric carcinomas. Among the 16 lesions, there were 14 (87.5%) early gastric carcinomas and two advanced carcinomas. Of the 14 early gastric carcinomas, two were minute (less than 5 mm in the largest diameter) early gastric carcinomas and four small (6-10 mm in the largest diameter). These gastric carcinomas were in a relatively early stage. The six early gastric carcinomas were not detected preoperatively. However, a thorough observation of the gastric mucosa could not be done in four of those due to stenosis which had developed as a result of the esophageal carcinoma. Therefore, intraoperative gastric observation should be done in cases in which the findings of the preoperative endoscopic examination of the stomach are inadequate and the upper gastrointestinal series reveal certain gastric abnormalities. 相似文献
6.
Predicting recurrence time of esophageal carcinoma through assessment of histologic factors and DNA ploidy 总被引:3,自引:0,他引:3
Cytophotometric analysis of nuclear DNA content was done in 128 patients with squamous cell carcinoma of the esophagus. The relationship among histopathologic features, DNA distribution pattern, and survival time was investigated from the standpoint of recurrence. Of 128 patients, 77 (60.1%) died of recurrence within 2 years after surgery: 16 (12.5%) from 2 to 5 years and two (1.6%) over 5 years. The rate of death of recurrence within 2 years was higher in patients with T4 or N1 than T1, T2, and T3 or N0 (P less than 0.01). Survivors over 5 years more frequently possessed type II DNA pattern than types III and IV (P less than 0.05). The rate of death of recurrence within 2 years was 34.4% in type II, which was lower than the 59.6% rate in type III (P less than 0.05) and the 76.6% rate in type IV (P less than 0.01). Survivors from 2 to 5 years were higher in type III than in type IV (P less than 0.05), and recurrence over 5 years was found only in type II. This inclination was more apparent in those with curative resection. In the patients with type II, careful follow-up may be needed over 5 years for late recurrence. However, in those with type IV, no recurrence over 2 years could be regarded as healed because most of their recurrences occur within 2 years. These findings suggest that the growth rate of esophageal carcinoma should reflect DNA aneuploidy, and the DNA analysis of esophageal carcinoma should be a valuable parameter for postoperative follow-up planning. 相似文献
7.
Mariko Hosono H. Kobayashi Ryota Fujimoto Kazushige Tsutsui Yoshihiko Kotoura Tadao Tsuboyama Hikaru Hayashi Takashi Nakamura Junji Konishi 《Skeletal radiology》1997,26(9):525-528
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with
plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast
T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense
rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have
this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant
disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. 相似文献
8.
Y Suzuki I Fukuda M Kohno T Jikuya M Wada T Tsutsui 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(3):472-476
Hemoptysis from bronchial collateral arteries in cyanotic heart diseases is a troublesome complication. We report a case of Tetralogy of Fallot presented with massive hemoptysis which was successfully treated with transcatheter therapeutic embolization prior to the radical operation. A 28-years old man was admitted to our hospital because of hemoptysis and dyspnea. On the day of admission, he had a massive hemoptysis and became asphyxic. Diagnostic cardiac catheterization performed next day revealed Tetralogy of Fallot. Bronchial arteriogram demonstrated large bronchial collateral arteries with heavy staining around the right lower lobe bronchus. Therapeutic embolization with Gelfoam was performed and the hemostasis was obtained. The radical operation was performed 4 months later. Before cardiopulmonary bypass, the right bronchial artery was ligated. He was weaned from the extracorporeal circulation under the stable circulatory condition, and respirator on the first post operative day without any complications, and he was discharged on the 57th day after the operation. We emphasize the efficacy of therapeutic embolization of the well developed bronchial collateral arteries as a pretreatment of hemoptysis in the cyanotic heart disease. 相似文献
9.
T Imai Y Takeki S Yamazaki A Yagoori M Niwa 《Nihon eiseigaku zasshi. Japanese journal of hygiene》1992,47(2):618-626
The long-term effects of low concentrations of sodium fluoride (0, 1 and 5 mg/l) in drinking water on bone metabolism were examined in the growing senescence accelerated mouse (SAM-P/6) as a spontaneous experimental model of senile osteoporosis. In 4 and 8 months of age respectively, there were almost no differences in body weight, and serum calcium, phosphorus and alkaline phosphatase levels between controls and fluoride groups. Calcium contents per dry weight of femoral bone were higher in fluoride groups than in controls. The bone mass of the trabecular was not affected by the low-concentration sodium fluoride intake. However, sodium fluoride decreased the rate of bone mass loss associated with aging in the cortical bone in SAM-P/6 compared with the control. The results of this study suggest that, in growing SAM-P/6 mice, a long-term low-concentration sodium fluoride intake affects the skeletal metabolism. 相似文献
10.