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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Yoshinori Yamashita Toshihiro Hirai Hidenori Mukaida Takashi Iwata Tetsuya Toge Hong Jae Hoon 《Surgery today》1990,20(6):671-676
This report presents the effect of repeated heating every 24 hrs using bleomycin (BLM) which, although seemingly contrary
to the usual agreement that hyperthermia should be carried out with a long interval due to thermotolerance, holds many possibilities.
FM3A cells on the foot pad of C3H mouse were immersed in a heated water bath at 43 and 44°C for 30 min. The effect of repeated
heating was appreciated by an improved growth curve and 50 day survival compared to mice which received heating twice with
a 96-hr interval. Repeated heating every 24 hrs 5 times with BLM suppressed tumor growth significantly as compared to heating
twice with a 96-hr interval without BLM. The longest survival time was obtained by the repeated heating with BLM among all
protocols. There is therefore a good possibility that more effective results could be obtained clinically by repeated heating
over a short period. 相似文献
32.
Yasuyuki Yamashita Katsuhiko Mitsuzaki Yi Tang Tomohiro Namimoto Mutsumasa Takahashi 《Journal of magnetic resonance imaging : JMRI》1997,7(4):623-628
MR angiography (MRA) was performed in 50 consecutive subjects (mean age, 59 years), who had been referred for abdominal MRA, on a 1.5-T superconductive unit that used a body phased-array coil. Three breath-hold three-dimensional sequences were evaluated both in phantom and clinical studies: (a) standard fast three-dimensional gradient-echo sequence (TR = 15, TE = 6; imaging time, 32 seconds), (b) ultrafast three-dimensional gradient-echo sequence (TR = 8.2, TE = 3; imaging time, 18 seconds), and (c) ultrafast magnetization-prepared (MP) rapid acquisition gradient echo (RAGE) (TR = 5.8, TE = 2.9, inversion time [TI] = 20; imaging time, 15 seconds). The initial 30 patients were randomized into three groups by three separate sequences. For the remaining 20 patients, ultrafast-gradient-echo and ultrafast MP-RAGE sequences were performed. Conventional angiography was performed on 36 patients. Signal measurements of the phantom and clinical images of the aorta, visceral branches of the aorta, iliac arteries, inferior vena cavae, and portal veins were performed. The overall image quality and background fatty tissue contrast of the vessels were rated subjectively. Comparison of images between MRA and conventional angiography also was performed. The contrast between the vessels and background fatty tissue was significantly higher in the ultrafast MP-RAGE sequence in both quantitative and qualitative analysis, and image-quality ultrafast MP-RAGE was superior to the other two sequences (P < .01). The aorta and iliac arteries could be visualized in all pulse sequences, and abnormalities of these vessels were diagnosed correctly. The renal artery was visualized more clearly with the two ultrafast sequences. 相似文献
33.
Cerebrovascular reserve capacity in ischemia due to occlusion of a major arterial trunk: studies by Xe-CT and the acetazolamide test. 总被引:2,自引:0,他引:2
T Yamashita M Hayashi S Kashiwagi S Nakano Y Eguchi T Takasago M Urakawa H Ito 《Journal of computer assisted tomography》1992,16(5):750-755
Classifications based on clinical and radiographic criteria have proved to be inadequate predictors of the course of cerebral ischemia or its response to therapy. In this study the cerebrovascular reserve capacity (CRC) of 46 patients with symptomatic cerebrovascular ischemia was studied by stable xenon-enhanced CT (Xe-CT) combined with the acetazolamide test. Fifteen patients had internal carotid artery (ICA) occlusion, 10 had ICA stenosis, 10 had middle cerebral artery (MCA) occlusion, and 11 had MCA stenosis. In the patients with chronic cerebral ischemia due to occlusive lesions of the ICA and MCA, the CRC was reduced most in those with MCA occlusion, followed, in descending order, by those with ICA stenosis, MCA stenosis, and ICA occlusion. Our results indicate that measurement of the CRC elucidates cerebral hemodynamic factors that cannot be detected by angiography in patients with chronic cerebral ischemia and that Xe-CT combined with the acetazolamide test is useful for this purpose. 相似文献
34.
Effects of a beta-agonist (isoproterenol) and beta-antagonists (propranolol and pindolol) on hypoxic pulmonary vasoconstriction (HPV) and on changes in some chemical mediators were compared between HPV-responsive lobes and non-responsive lobes in which HPV was induced by aspirin DL-lysine (ASA groups). Hypoxic ventilation (4 min) was repeated in 56 of isolated, blood-perfused dog lung lobes. Each drug was administrated in a bolus dose of 0.2 mg in the intermittent period between hypoxia. In HPV-responsive lobes, the first hypoxia increased pulmonary vascular resistance by 33% or more in all groups. Both isoproterenol and pindolol inhibited the elicitation of HPV completely, but propranolol induced almost the same degree of HPV as control. In ASA groups, HPV was completely inhibited by isoproterenol, but was not influenced by propranolol. However, pindolol's inhibitory effect on HPV was less than that in HPV-responsive lobes. Isoproterenol significantly increased cyclic AMP from 17.0 to 76.7 pmol/ml in HPV-responsive lobes (n = 7). Pindolol increased prostaglandin E2 from 87.0 to 1015.4 pg/ml in HPV-responsive lobes (n = 7), and from 93.4 to 361.3 pg/ml when ASA was treated. Propranolol did not show the different results from the control group whether ASA was present or not. The different mechanisms among beta-adrenoceptor-related agents in HPV and pulmonary circulation were investigated. 相似文献
35.
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
36.
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38.
Takashi Ishimori Satoru Nakano Masahiro Kagawa Koiku Yokoe Tarou Togami Hirofumi Asakura Toshiaki Kusuhara Motoomi Ohkawa Syeigo Nagao Yuichi Yamashita Satoshi Sugiura 《Magnetic resonance in medical sciences》2003,2(3):145-149
Three-dimensional fast asymmetric spin echo (3D FASE) cisternography provides high spatial resolution and excellent contrast as a water image acquisition technique. It is also useful for the evaluation of various anatomical regions. This study investigated the usefulness and limitations of virtual endoscopic images obtained by 3D FASE MR cisternography in the preoperative evaluation of patients with neurovascular compression. The study included 12 patients with neurovascular compression: 10 with hemifacial spasm and two with trigeminal neuralgia. The diagnosis was surgically confirmed in all patients. The virtual endoscopic images obtained were judged to be of acceptable quality for interpretation in all cases. The areas of compression identified in preoperative diagnosis with virtual endoscopic images showed good agreement with those observed from surgery, except in one case in which the common trunk of the anterior inferior cerebellar artery and posterior inferior cerebellar artery (AICA-PICA) bifurcated near the root exit zone of the facial nerve. The veins are displayed in some cases but not in others. The main advantage of generating virtual endoscopic images is that such images can be used for surgical simulation, allowing the neurosurgeon to perform surgical procedures with greater confidence. 相似文献
39.
Cerebral vasculitis secondary to Wegener's granulomatosis: computed tomography and angiographic findings 总被引:1,自引:0,他引:1
Y Yamashita M Takahashi H Bussaka M Miyawaki K Tosaka 《The Journal of computed tomography》1986,10(2):115-120
The central nervous system is rarely involved by Wegener's granulomatosis. A case of Wegener's granulomatosis with involvement of the cerebral arteries was reported. Computed tomography showed extensive brain edema with angiographic demonstration of cerebral vasculitis. 相似文献
40.
K Yamashita K Shigematsu T Maeda Y Ishida M Niwa M Ozaki 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1989,93(1):7-15
The antihypertensive effect of bopindolol, a long-acting beta-adrenoceptor blocking agent, was investigated in stroke-prone spontaneously hypertensive rats (SHRSP). One group received tap water during the period of 8 to 32 weeks of age. The average dose of bopindolol administered was calculated from water intake to be approximately 1.4 mg/kg/day. The lowering effect in blood pressure of bopindolol was apparent at the age of 14 weeks, and this continued up to the end of the experiment. Bopindolol significantly reduced the heart rate. Plasma levels of urea nitrogen (BUN), triglyceride, and phospholipid of SHRSP treated with bopindolol were lower than those of the control SHRSP. One of the 8 control SHRSP died, and no rats treated with bopindolol died during the experiment. The histopathological study revealed that three of the control SHRSP had cerebral apoplexy, whereas there was no evidence of cerebral apoplexy in the treated SHRSP. Chronic treatment of bopindolol clearly alleviated myocardial fibrosis and hypertrophic changes in the left ventricular wall of the heart. Decreases in the incidence of proliferative arteritis and malignant nephrosclerosis in the kidney and necrotizing arteritis of the mesenteric arteries were observed in SHRSP treated with bopindolol. The data presented indicate that bopindolol is a powerful antihypertensive agent. 相似文献