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OBJECTIVE: To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences. METHODS: The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography. RESULTS: In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed. CONCLUSIONS: Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium.  相似文献   
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Renal cell carcinoma (RCC) causes many kinds of symptoms such as hypercalcemia, hypertension, polycythemia and fever. Here we describe a rare case of RCC presenting with a persistent cough. After radical nephrectomy, the obstinate cough disappeared. When the tumor recurred locally, the cough also recurred. Furthermore, the cough disappeared completely again after the removal of the recurrent tumor. Although all the clinical findings suggested that the RCC caused the cough, we could not identify a specific humoral substance responsible for the cough.  相似文献   
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OBJECTIVE: To evaluate the initial results of brachytherapy for prostate cancer with permanent iodine-125 implant in Japan. METHODS: The results obtained with brachytherapy in the initial 100 Japanese patients treated at Nagano Municipal Hospital were reviewed. Patients with a prostate-specific antigen (PSA) level of less than 10 ng/mL and a Gleason's scores of 5, 6, 3 + 4 were classified as having a low risk of recurrence. Patients with a PSA level of 10-20 ng/mL and/or a Gleason's score of 4 + 3 were classified as having an intermediate risk for recurrence. Seventy-eight of the low-risk patients and 19 of the intermediate-risk patients were treated by seed implants alone, or seed implants combined with preceding external radiation, respectively. A total of 53 patients received neoadjuvant hormone therapy. The efficacy and morbidity of brachytherapy were investigated using the serum PSA, International Prostate Symptom Score, quality of life score and uroflowmetry data. RESULTS: The average V100 and D90 obtained by post-implant dosimetry was 94.3 and 113.7%, respectively. Serum PSA decreased gradually after treatment, although it had still not reached a nadir after 1 year. There was little difference of the PSA level between the patients with and without neoadjuvant hormone therapy even at 1 year after seed implantation. There were no PSA biochemical failure or clinical recurrence during the follow-up period. Voiding symptoms worsened until 3 months after treatment, and then gradually improved. Acute urinary retention occurred transiently in one patient (1%). Rectal bleeding and severe diarrhea did not occur. CONCLUSION: Brachytherapy is a feasible and effective option for the treatment of prostate cancer in Japanese men. Brachytherapy may have a different effect in Japanese patients with respect to voiding symptoms. Urinary retention was rare, but voiding symptoms were persistent in Japanese patients. Neoadjuvant hormone therapy deserves investigation to determine whether it can achieve better results, especially in patients with an intermediate risk.  相似文献   
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Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future.  相似文献   
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The mechanism of the vasodilator effect of pinacidil was examined. Pinacidil (0.1–100 μM) inhibited the increases in cytosolic Ca2+ ([Ca2+]i) and muscle tension due to norepinephrine in rat aorta. In contrast, a Ca2+ channel blocker, verapamil, inhibited the norepinephrine-stimulated [Ca2+]i more strongly than the contraction. Higher concentrations of pinacidil (3–100 μM) inhibited the verapamil-insensitive portion of the contraction and [Ca2+]i. An inhibitor of ATP-sensitive K+ channels, glibenclamide, antagonized the inhibitory effect of low concentrations ( 10 pM) of pinacidol. Pinacidil did not change the contraction induced by Ca2+ in vascular smooth muscle permeabilized with Staphylococcus aureus -toxin. Norepinephrine (in the presence of GTP), 12-deoxyphorbol 13-isobutyrate (in the absence of GTP), and treatment with GTPγS potentiated the contraction of permeabilized smooth muscle induced by the addition of Ca2+. Pinacidil (100 μM) inhibited the potentiation due to GTPγS or noepinephrine but not to phorbol ester. These results suggest that pinacidil has dual effects on vascular smooth muscle contraction. At lower concentrations (>0.1 μM), it decreases [Ca2+]i, possibly by activating ATP-sensitive K+ channels. At higher concentrations (> 3 μM), it may additionally inhibit the receptor-mediated, GTP-binding protein-coupled phosphatidyl inositol turnover.  相似文献   
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Between November 1986 and April 1989, 101 patients with superficial bladder cancer were treated with intravesical instillations of mitomycin C on day 1 and doxorubicin on day 2 of each week for 5 consecutive weeks. Of 61 complete responders, 23 patients with carcinoma in situ and 28 with papillary cancer were randomly assigned to a non-maintenance group or to a group receiving maintenance therapy consisting of monthly instillations of the same drugs for 12 months. The 2-year non-recurrence rate calculated for patients with carcinoma in situ was significantly better in the maintenance group than in the non-maintenance group. A similar tendency was observed for patients with papillary cancer, although the difference was not significant. Side effects were considerable, with moderate to severe bladder irritation occurring in approximately half of the patients. In addition to our previous findings, the present results indicate that this intravesical combination chemotherapy is effective in eliminating superficial bladder cancers and that since the effect is not durable, even in complete responders, maintenance therapy is necessary to reduce subsequent tumor recurrence.Presented at the 4th International Conference on Treatment of Urinary Tract Tumors with Adriamycin/Farmorubicin, 16–17 November 1990, Osaka, Japan  相似文献   
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From October, 1980, to June, 1987, thirty-eight infants less than one year old underwent correction for total anomalous pulmonary venous connection (TAPVC). Overall operative mortality and late mortality were 13% and 6%, respectively. Residual pulmonary hypertension was noted in 4 patients: three had pulmonary venous obstruction at the site of atrial anastomosis (PVOA) and one had supracardiac (Ia) lesion left after repair of mixed type (IV: Ia + III) of TAPVC. Two late deaths occurred in these with PVOA. Twenty-two patients with supracardiac (I) or infracardiac (III) TAPVC were divided into three groups according to the technical development in atrial anastomosis: the large anastomosis in which venous incision reached into at least one pulmonary vein beyond common pulmonary vein and the continuous running suture were used in 10 patients (group 1), the appropriate size of anastomosis in which venous incision limited within the common pulmonary vein and the continuous running suture used in 4 patients (group 2), and the appropriate size of anastomosis and the interrupted suture in 8 patients (group 3). PVOA were 3 (33%) in group 1, but 0 (0%) in group 2 and 3. Two late death occurred all in group 1 with PVOA. Cardiopulmonary bypass time and aortic clamp time in group 3 were 91 min and 74 min respectively, which did not become longer than those in both group 1 and group 2. Interrupted suture technique does not make operating time longer than continuous running suture one. PVOA is one of the important factors predicting late operative result.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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