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排序方式: 共有2221条查询结果,搜索用时 15 毫秒
1.
Shingo Hashimoto Masaki Katsurada Rie Muramatsu Kumiko Asai Kenichiro Tanaka Kensuke Hayashi Yoshiaki Kibe Koichiro Nakajima Yukiko Hattori Hiromitsu Iwata Jun-etsu Mizoe Hiroyuki Ogino Yuta Shibamoto 《Practical radiation oncology》2019,9(2):e149-e155
Purpose
Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.Methods and Materials
First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.Results
The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.Conclusions
The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target. 相似文献2.
3.
Sho Takahashi Hisato Homma Takehide Akiyama Shinichi Mesawa Kenichiro Hirata Katsuhisa Kogawa Kunihiro Takanashi Hirotoshi Ishiwatari Yutaka Kawano Tsuyoshi Hayashi Kohichi Takada Koji Miyanishi Junji Kato Yoshiro Niitsu 《Nihon Shokakibyo Gakkai zasshi》2007,104(8):1236-1244
A 75-year-old man had been admitted to another hospital because of left abdominal pain, and was given a diagnosis of left hydronephrosis and acute pancreatitis. After a JJ stent insertion and medication, he was transferred to our hospital for further examinations. US and EUS revealed a chronic pancreatitis-like pattern and multicystic lesion in the pancreas head and body. At that time enhanced CT findings showed an extrapancreatic low density area to be inflammatory change, extending from the pancreas body to the left crus of the diaphragm and posteriorly the spreading from the left crus of the diaphragm via the left urinary duct into the left iliopsoas muscle, in which MRI revealed partial high intensity. ERCP and MRCP showed focal irregular narrowing of the pancreatic duct of unknown cause, and we decided that an internal pancreatic fistula due to pancreatitis had induced left ureteral obstruction, caused by a protein plug or alcohol. Follow-up 6 months later showed that extrapancreatic spreading of the low density area had markedly regressed without any change in the ureteral obstruction. 相似文献
4.
Kenichiro Mikawa Hiroaki Kume Kenzo Takagi 《Clinical and experimental pharmacology & physiology》1997,24(2):175-181
1. In order to examine the mechanisms of cGMP-induced relaxation in airway smooth muscle, the effects of atrial natriuretic peptide (ANP) and 8-brom cGMP on muscle tone were studied by measuring isometric tension, while the effects on cytosolic Ca2+ concentrations were studied by measuring the spectra of fura-2 loaded in guinea-pig tracheal strips. 2. Atrial natriuretic peptide and 8-brom cGMP caused a concentration-dependent inhibition of spontaneous tone in the guinea-pig trachea. The relaxant effects of these agents on spontaneous tone were markedly suppressed in the presence of iberiotoxin (IbTX), a selective inhibitor of large-conductance Ca2+-activated K+ (BKca) channels. Iberiotoxin (30 nmol/L) markedly affected the maximal effect induced by ANP and 8-brom cGMP and augmented EC70 values for ANP and EC50values for 8-brom cGMP approximately 27- and 17-fold, respectively. The inhibitory effects of IbTX on relaxation induced by these agents were diminished in the presence of 1 μmol/L nifedipine, an antagonist of voltage-operated Ca2+channels (VOCC). 3. The inhibitory action of ANP and 8-brom cGMP on spontaneous tone was not affected by the presence of 10 μmol/L glibenclamide, an inhibitor of ATP-sensitive K+ channels, and 100 nmol/L apamin, an inhibitor of small-conductance Ca2+-activated K+ channels. When these agents were applied to tissues precontracted by high (40mmol/L) K+, the relaxant effects of these agents markedly diminished. 4. The extracellular Ca2+-dependent contraction was inhibited in the presence of 0.3 μmoI/L ANP or 0.1 mmol/L 8-brom cGMP. Concentration—response curves to extracellular Ca2+ (0.03—2.4 mmol/L) were markedly diminished by exposure to these agents. The maximal effect induced by extracellular Ca2+ was affected by these agents. 5. Atrial natriuretic peptide caused an inhibition of spontaneous tone accompanied by a reduction in the intracellular Ca2+ concentration. In the presence of IbTX, the elimination of both muscle tone and cytosolic Ca2+ by ANP was suppressed. 6. We conclude that ANP and 8-brom cGMP activate BKca channels and that the inhibition of Ca2+ influx through VOCC, mediated by BKca channel activation, may be involved in cGMP-dependent bronchodilation. 相似文献
5.
M Yabuki 《Ryūmachi》1991,31(1):4-13
The radio activity of 131I-Hippuran injected into the knees was investigated in rabbits and found to decrease with passage of the time. The disappearance curve was monoexponential and the disappearance rate was able to be obtained by a biological half life (T 1/2). This evidence showed that 131I-Hippuran was absorbed from the knee and excreted into body blood circulation but was not able to return to the knee again, and might provide a suitable parameter for the joint clearance. The mean value of T 1/2 in normal 25 knees was 13.9 +/- 4.5 min. The effect of 0.1N oxalic acid on the T 1/2 was investigated in 20 knees 24 hours after intra-articular injection, in 17 knees 4 days, in 14 knees 7 days, in 11 knees 12 days and in 9 knees 20 days. The mean T 1/2 value was 50.4 +/- 9.8 min., 30.6 +/- 6.2 min., 20.9 +/- 4.4 min., 15.2 +/- 2.2 min., and 13.7 +/- 2.5 min., respectively. The significant difference was observed between the groups of 24 hours, 4 days and 7 days. Hemorrhagic arthritis was observed in the rabbit knee with oxalic acid injection. The very severe hemorrhagic change was observed in the specimen obtained 24 hours and 4 days after the injection. On the 7 days after that the arthritic condition began to heal and almost complete healing was observed on 12 to 20 days. These results indicated that the joint clearance of 131I-Hippuran was reflected well in the pathological change induced by oxalic acid. It is interpreted to mean that the inhibition of synovial blood circulation by oxalic acid might cause decrease of absorption and clearance rate of 131I-Hippuran in the knee. It is thought that the measurement of the biological half life (T 1/2) after the intra-articular injection of 131I-Hippuran is a suitable method mainly to understand the condition of absorption and excretion of the joint through the synovial blood vessels. 相似文献
6.
High incidence of multiple kidney stone formation has been observed among workers exposed to cadmium (Cd). Citrate is known to be a protective factor against renal stone formation. To study the direct effect of cadmium on citrate uptake by the renal brush border membrane, we exposed isolated rat renal brush border membrane vesicles (BBMV) to cadmium and determined their citrate uptake characteristics. BBMV were prepared by the divalent cation precipitation method. Citrate uptake was measured by the Millipore rapid membrane filtration technique. Preincubation of BBMV with 2 and 10 mM CdCl2 for 1 min significantly inhibited citrate uptake compared with that of BBMV without Cd. Analysis of the time course of citrate uptake during 30-min preincubation of BBMV with 0.5 mM Cd also revealed significant reduction of the uptake compared with that of the control BBMV without preincubation. These findings indicate that preincubation of BBMV with cadmium results in time-dependent and concentration-dependent inhibition of citrate uptake. 相似文献
7.
T Maekawa K Yabuki K Satou G Mishima Y Tamasaki S Watabe S Shirota 《Nippon geka hokan》1997,66(4):116-125
We describe our experience with a patient in whom a traumatic right diaphragmatic hernia developed 4 years after sustaining injury and review cases of delayed diaphragmatic injury reported in Japan. The patient was a 28-year-old man who sustained a severe contusion of the right epigastric region and fractured a right rib in a traffic accident in September 1992. In August 1996, the patient presented with shortness of breath on effort or after meals. A chest roentgenogram revealed intestinal gas in the right side of the thoracic cavity. A right diaphragmatic hernia was diagnosed on the basis of a gastrointestinal series, and the patient was operated on. The hernial orifice extended anteriorly from the central tendon in an 11:00 direction and measured 11 x 6 cm. The small intestine, right side of the colon, and liver were herniated. A total of 297 cases of blunt traumatic diaphragmatic hernia were reported in Japan between 1981 and 1996, including 47 cases (left side, 32 cases; right side, 15 cases) of delayed diaphragmatic hernia, defined as occurring one month or more after injury. Diaphragmatic hernia should be considered as a possible diagnosis in patients with abnormal shadows in the thoracic region who have recently sustained injury or who have a past history of injury. 相似文献
8.
Ichiro Ikegaki Yoshio Suzuki Shin-ichi Satoh Toshio Asano Masato Shibuya Kenichiro Sugita 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(4):431-436
Summary The effects of calcitonin gene-related peptide (CGRP) on canine cerebral arteries and on vertebral blood flow were investigated in-vivo and in-vitro and the findings compared with the effects of vasoactive intestinal peptide (VIP) and substance P. Administration of CGRP into the vertebral artery caused a dose-dependent and long-lasting increase in blood flow. The in-vivo vasodilatory effects of substance P and VIP were short-lasting. CGRP (0.1 to 100 nmol/l) elicited a concentration-dependent relaxation of the isolated middle cerebral and basilar arteries when the tissues were precontracted by exposure to prostaglandin F2 (PGF2). This effect was not antagonized by propranolol, atropine, tetrodotoxin, (N-Ac-Tyr1, D-Phe2)-growth hormone-releasing factor(1–29)-NH2 or (D-Pro2, D-Trp7,9) substance P. CGRP also reduced concentration-dependently the contraction of cerebral arteries induced by KCl or 9,11-epithio-11,12-metano-thromboxane A2 (STXA2). Mechanical removal of the endothelium did not abolish the vasodilatory response to CGRP. In PGF2-contracted canine cerebral arteries, VIP (0.1 to 100 nmol/l) was less potent a vasodilator than CGRP. At low concentrations (0.01 to 1 nmol/l) substance P elicited a rapid and short-lasting relaxation, and in the absence of endothelium this relaxation disappeared. These findings are clear evidence that CGRP modulates vascular tone. 相似文献
9.
Yabuki T Togami I Kitagawa T Sasai N Tsushima T Shirasaki Y Hiraki Y 《Acta medica Okayama》2003,57(4):179-186
The purpose of this study was to compare the MR characteristics of renal cell carcinomas against histologic findings and to assess the correlations among signal intensity, tumor enhancement, and pathologic findings. Fifty-four patients (56 lesions) were examined by MR imaging and then underwent partial or radical nephrectomy. The pathologic diagnosis of all lesions was renal cell carcinoma. All MR examinations were performed as dynamic studies using the same 1.5-T scanner. MR characteristics were compared against pathologic findings after resection, and the correlations among signal intensity, tumor enhancement, and pathologic findings were then assessed. A significant correlation was observed between tumor grade and tumor enhancement, with G3 lesions tending to show little enhancement. Regardless of the histologic classification, G3 tumors were found to contain highly heterotypic cancer cells and very few vessels by histopathologic examination. No significant correlations were noted between the other MR characteristics and pathologic findings. Renal cell carcinomas showing little enhancement tend to be highly malignant lesions based on the pathologic findings. Special consideration is required for these tumors with regard to the selection of surgical intervention and follow-up observation. 相似文献
10.
Our previous study showed that the saliency of a target increases the gain of smooth pursuit initiation. In this study, we examined the interocular transfer of this effect in five humans. A square red frame surrounding the target was used as a cue to indicate the initial target position. In the cue condition, the responses were similar, irrespective of the eye to which the cue was presented, and were significantly larger than in the no-cue condition. The result suggests that central pathways that receive input from both eyes mediate the effect of saliency on smooth pursuit initiation. 相似文献