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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.
Marie Ohata Susumu Fujiwara Ai Yoshioka Hiroshi Nagai Shintaro Sugita Nozomi Yamano Yusuke Inoue Chikako Nishigori 《Pediatric dermatology》2019,36(6):997-998
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy. 相似文献
4.
Takamasa Kaneko Koichi Makimura Takashi Sugita Hideyo Yamaguchi 《Medical mycology》2006,44(3):227-231
We developed a simple identification kit for nine species of Malassezia (M. furfur, M. slooffiae, M. sympodialis, M. restricta, M. obtusa, M. globosa, M. pachydermatis, M. dermatis, and M. japonica) based on their biological features. This method utilizes Tween 40-based precipitate production on modified chromogenic agar (CHROMagar) Malassezia medium, growth on specific agars (Sabouraud's dextrose agar, Cremophor EL agar, Tween 60-esculin agar), and catalase reactions. This identification kit was verified with 11 type and reference strains of nine Malassezia species. An additional 26 clinical isolates were also successfully identified using the kit and the results were confirmed by molecular biological analysis. 相似文献
5.
6.
For heavy metals, many studies obtained short biological half-times (BHTs) by administrations of heavy metals. Tsuchiya and Sugita, however, first reported the possibility of a long BHT for cadmium (Cd) calculated from Cd accumulations in postmortem human organs and tissues by age using a non-linear regression method employing a differential equation. According to their reports, the Cd BHTs (point estimators) were 12.1-22.7 years by sex, renal cortex and medulla. The minimums and the maximums of the Cd BHTs on the 95% confidence regions of estimators were 6.9-70.2 years by sex and kidney part. It is presumed that the range of the 95% confidence region for the individual BHTs of renal Cd exists in a range from a few years to at least 100 years because of large individual variations in exposure, absorption rate and excretion rate. Point estimators of BHTs, however, include the assumption that all subjects have been exposed to the same level of Cd at the same year of age over a period of decades and have equal absorption and excretion rates of Cd. Therefore, it is not adequate to calculate a safety level for Cd in the industrial environment or foodstuffs using a value of Cd BHT (point estimator) based on Cd accumulation applying a mathematical model. BHTs of metals require careful evaluation and must not be used indiscriminately to derive a critical concentration, for example, using a mathematical model. 相似文献
7.
A head fixation system using four carbon fiber head pins and modified pin supporting devices is described. The fixation system was developed for intraoperative computed tomographic scanning and provides artifact-free images during open-field neurosurgery. 相似文献
8.
Production of the first offspring from oocytes derived from fresh and cryopreserved pre-antral follicles of adult mice 总被引:2,自引:0,他引:2
Kagawa N Kuwayama M Nakata K Vajta G Silber S Manabe N Kato O 《Reproductive biomedicine online》2007,14(6):693-699
Although mammalian ovaries contain hundreds of thousands of pre-antral follicles, fewer than 1% of these reach maturity and ovulation. Obtaining immature eggs from the pre-antral follicles of ovarian tissue could increase the possibility of preserving fertility in women undergoing anti-cancer treatment, and in women who wish to delay pregnancy and child raising until they are older. This study reports the birth of 10 healthy mouse pups derived from oocytes obtained from pre-antral follicles after adult ovary tissue cryopreservation and allotransplantation. High in-vitro maturation (55.1%), fertilization (76.3%) and cleavage (98.3%) rates were achieved using these oocytes, and there was no significant difference between the vitrified and control samples except in maturation rate (55.1 versus 72.8%, P < 0.05). After an ultra-rapid vitrification procedure, the warmed tissue fragments were transplanted beneath the kidney capsule of severe combined immunodeficient mice for onward in-vivo culture. Within 10 days of culture, 138 full size oocytes developed from the 456 transplanted pre-antral follicles. In-vivo growth of follicles was followed by in-vitro oocyte maturation, in-vitro fertilization and subsequent embryo transfer, leading to the birth of 10 healthy pups. These results may lead to increasing the possibility of preserving fertility by cryopreservation of ovarian tissue. 相似文献
9.
10.
Summary Effects of STA-MCA anastomosis on two patients with neovascular glaucoma due to occlusion of the internal carotid artery are presented. Both patients improved in visual acuity and central retinal artery pressure as well as in signs of transient ischaemic attack. Postoperative angiography showed a marked decrease in collateral flow through the ophthalmic artery, which is reversed from the normal direction, with the development of blood flow through the anastomosis. Discussion is offered indicating that the lack of collateral flow through both the anterior and posterior communicating arteries is important in addition to occlusion of the internal carotid artery in order to produce full-blown ischaemic oculopathy such as venous stasis retinopathy, neovascular glaucoma or rubeosis iridis. It is stressed that EC-IC bypass surgery should be performed soon after the appearance of ischaemia and before the development of neovascular glaucoma or rubeosis iridis in order to obtain normal vision. In ischaemic oculopathy the results of EC-IC bypass can be evaluated objectively and quantitatively by many noninvasive neuro-ophthalmological tests which are important in discussing the efficacy of the bypass surgery. 相似文献