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排序方式: 共有4238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.
K Funaishi K Kawamura F Satoh M Hiramatsu M Hagiwara M Okanish 《The Journal of antibiotics》1990,43(8):938-947
Antibiotics 6108 A1, B, C and D, a new series of analogues of rosaramicin, were found together with rosaramicin, juvenimicin A4 and M-4365 A1 from the cultured broth of strain BA06108 which was assigned to be a new species of Micromonospora. 6108 A1 and C showed inhibitory activity against Gram-positive and some Gram-negative bacteria as potent as rosaramicin and exhibited low acute toxicity in mice. However, 6108 B showed less potent antimicrobial activity and 6108 D showed higher toxicity than those two antibiotics. 相似文献
4.
K Okuchi Y Watabe K Hiramatsu T Tada T Sakaki K Kyoi S Utsumi K Kamada H Ohnishi T Shimomura 《No shinkei geka. Neurological surgery》1990,18(8):721-727
Although it is well known that Wallenberg's syndrome is caused by occlusion of the vertebral artery (VA) or the posterior inferior cerebellar artery (PICA), the etiology of the occlusion is rarely documented. During the course of Wallenberg's syndrome, patients often complain of headache. We thought that these headaches might be caused by dissecting aneurysm (DA) of the vertebral artery, and so we studied the incidence of DA in our cases with Wallenberg's syndrome. Although many variants exist, Wallenberg's syndrome encompasses several neurological symptoms due to a disorder of the nucleus and nerve tracts located in the lateral part of the medulla. We diagnosed our patients as having Wallenberg's syndrome on the basis of symptoms such as loss of pain and temperature sensation in the unilateral face and contralateral body, cerebellar ataxia, and dysphasia. We investigated 22 cases of Wallenberg's syndrome over a five-year period, and excluded patients who developed subarachnoid hemorrhage upon onset of the syndrome. Our cases can be divided into two groups; one with severe stenosis or occlusion of VA (n = 15) and the other with occlusion of PICA (n = 5). The angiograms of the two remaining patients showed no abnormal findings. The mean age of the VA group (42.5 yrs.) was younger than that of the PICA group (64.2 yrs.). The age distribution of the PICA group is similar to that of other occlusive cerebrovascular diseases. Seven cases of the VA group demonstrated aneurysmal dilatation and luminal stenosis, and so they were diagnosed as having dissecting aneurysm of VA.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
M. Fujioka K. Okuchi S. Miyamoto T. Sakaki K. Hiramatsu M. Tominaga Y. Kamada S. Iwasaki 《Neuroradiology》1994,36(8):605-607
We report specific changes bilaterally in the basal ganglia and thalamus following reperfusion after complete cerebral ischaemia. A 69-year-old man, resuscitated after cardiac arrest, showed symmetrical lowdensity lesions in the head of the caudate nucleus and lentiform nucleus on CT. MRI revealed methaemoglobin derived from minor haemorrhage in the basal ganglia and thalamus, not evident on CT. We suggest that this haemorrhage results from diapedesis of red blood cells through the damaged capillary endothelium following reperfusion. 相似文献
6.
László Prónai Hiroe Nakazawa Kohji Ichimori Yoshinori Saigusa Tomoichi Ohkubo Kazuko Hiramatsu Shigeru Arimori János Fehér 《Inflammation》1992,16(5):437-450
This study was performed to examine the pattern of Superoxide (O
2
–
·) generation from leukocytes using the O
2
–
· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O
2
–
· generation by leukocytes. The time course of O
2
–
· generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O
2
–
· for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O
2
–
· generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O
2
–
· much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O
2
–
· generation by leukocytes. 相似文献
7.
8.
SeveralChlorellavirus CVK2 proteins had chitosanase and/or chitinase activities. A gene coding for an ORF of 328 amino acids (aa) with a predicted molecular mass of 36,769 Da was cloned from the viral genome. The predicted amino acid sequence of an N′-portion (174 aa) of this gene product (vChta-1) showed 22 to 25% identity with various bacterial chitosanases. A glutathioneS-transferase (GST)–vChta-1 fusion protein had strong chitosanase activity. Western blot analysis with antisera raised against the vChta-1 protein identified two proteins of 37 and 65 kDa in virus-infectedChlorellacells beginning at 240 min postinfection and continuing until cell lysis. The larger protein was packaged in the virion, while the smaller one remained in the cell lysate. Both chitosanase proteins were produced from the single gene,vChta-1,by a mechanism of alternative gene expression. 相似文献
9.
Shinichiro Kitada Kumiko Kato Alan J. Wein Robert M. Levin 《Neurourology and urodynamics》1989,8(3):255-262
We were able to produce two highly reproducible experimental models (in the rabbit) that demonstrated a high degree of reflex bladder contractile activity. In one model, a somatovesical reflex was induced by touching or pinching the perineal area. This reflex may be organized through a neurogenic reflex at the spinal level. In another model, rhythmic bladder contractions were produced by distal urethral constriction in the absence of bladder distension. These rhythmic contractions were thought to be due to a supraspinal reflex. In both types of contractile reflexes, intravenous administration of hexamethonium inhibited the reflex contractile activity virtually completely, intravenous atropine inhibited over 90% of the induced contractile activity, thus suggesting that these contractions were mediated reflexly through cholinergic stimulation. These two models of reflex bladder contractions should be useful for the study of hyperreflexic bladders. 相似文献
10.