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      • KCI등재

        Photochemical Response in 0-Year-Old and 1-Year-Old Needles of Picea glehnii during Cold Acclimation and Low Temperature

        배정진,Toshihiko Hara,추연식 한국생태학회 2008 Journal of Ecology and Environment Vol.31 No.4

        P. glehnii, an evergreen conifer found in northern areas, is known as a cold-resistant species. In this experiment, we measured the water content, PSⅡ efficiency, chlorophyll fluorescence, pigments of the xanthophyll-cycle and activity of enzymes of the ascorbate-glutathione cycle during cold acclimation and at subsequent low-temperature conditions to examine the importance of acclimation to cold tolerance. P. glehnii showed a decrease in PSⅡ efficiency (especially in Fv) during cold acclimation and at subsequent low temperatures. However, cold-acclimated needles showed higher PSⅡ efficiency at low temperatures than nonacclimated needles. In addition, 0-YON (first-year needles) showed an increase in β-carotene and lutein, while 1-YON (one-year-old needles) immediately developed an antioxidant mechanism in the ascorbate-gluthathione cycle as soon as they were exposed to low temperature and both 0-YON and 1-YON showed increased zeaxanthin and de-epoxidation ratios at continuous low temperature. Based on our results, we suggest that P. glehnii maintain PSⅡ efficiency at low temperature by effectively protecting the photosynthetic apparatus from photo-damage by rapid induction of an antioxidant mechanism in 1-YON and dissipation of excess energy by β-carotene and lutein in 0-YON. P. glehnii, an evergreen conifer found in northern areas, is known as a cold-resistant species. In this experiment, we measured the water content, PSⅡ efficiency, chlorophyll fluorescence, pigments of the xanthophyll-cycle and activity of enzymes of the ascorbate-glutathione cycle during cold acclimation and at subsequent low-temperature conditions to examine the importance of acclimation to cold tolerance. P. glehnii showed a decrease in PSⅡ efficiency (especially in Fv) during cold acclimation and at subsequent low temperatures. However, cold-acclimated needles showed higher PSⅡ efficiency at low temperatures than nonacclimated needles. In addition, 0-YON (first-year needles) showed an increase in β-carotene and lutein, while 1-YON (one-year-old needles) immediately developed an antioxidant mechanism in the ascorbate-gluthathione cycle as soon as they were exposed to low temperature and both 0-YON and 1-YON showed increased zeaxanthin and de-epoxidation ratios at continuous low temperature. Based on our results, we suggest that P. glehnii maintain PSⅡ efficiency at low temperature by effectively protecting the photosynthetic apparatus from photo-damage by rapid induction of an antioxidant mechanism in 1-YON and dissipation of excess energy by β-carotene and lutein in 0-YON.

      • SCOPUSSCIEKCI등재

        A Morphologically Atypical Case of Atlantoaxial Rotatory Subluxation

        Umebayashi, Daisuke,Hara, Masahito,Nishimura, Yusuke,Wakabayashi, Toshihiko The Korean Neurosurgical Society 2014 Journal of Korean neurosurgical society Vol.55 No.5

        A rare case of atlantoaxial rotatory subluxation occurred after pediatric cervical spine surgery performed to remove a dumbbell-shaped meningioma at the level of the C1/C2 vertebrae. This case is classified as a post-surgical atlantoaxial rotatory subluxation, but has a very rare morphology that has not previously been reported. Although there are several reports about post-surgical atlantoaxial rotatory subluxation, an important point of this case is that it might be directly related to the spinal cord surgery in C1/C2 level. On day 6 after surgery, the patient presented with the Cock Robin position, and a computed tomography scan revealed a normal type of atlantoaxial rotatory subluxation. Manual reduction was performed followed by external fixation with a neck collar. About 7 months after the first surgery, the subluxation became severe, irreducible, and assumed an atypical form where the anterior tubercle of C1 migrated to a cranial position, and the posterior tubercle of C1 and the occipital bone leaned in a caudal direction. The pathogenic process suggested deformity of the occipital condyle and bilateral C2 superior facets with atlantooccipital subluxation. A second operation for reduction and fixation was performed, and the subluxation was stabilized by posterior fixation. We encountered an unusual case of a refractory subluxation that was associated with an atypical deformity of the upper spine. The case was successfully managed by posterior fixation.

      • SCIESCOPUSKCI등재

        Esophagography in Patients With Esophageal Achalasia Diagnosed With High-resolution Esophageal Manometry

        ( Takahisa Yamasaki ),( Toshihiko Tomita ),( Sumire Mori ),( Mayu Takimoto ),( Akio Tamura ),( Ken Hara ),( Takashi Kondo ),( Tomoaki Kono ),( Katsuyuki Tozawa ),( Yoshio Ohda ),( Tadayuki Oshima ),( 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2018 Journal of Neurogastroenterology and Motility (JNM Vol.24 No.3

        Background/Aims High-resolution esophageal manometry (HREM) is considered to be the gold standard for the diagnosis of achalasia. However, the Japan Esophageal Society recommends that esophagography is also accurate in either diagnosing or excluding the disorder. Accordingly, we compared the efficacy of esophagography and HREM in diagnosing achalasia patients with upper gastrointestinal symptoms. Methods HREM was performed in 126 patients with dysphagia. The final diagnosis of achalasia was done using HREM. Demographic data, symptoms, quality of life (QOL) were also obtained. We assessed the patients who were not able to be diagnosed by esophagography and compared the diagnostic values for esophagography with HREM-based achalasia diagnosis as the gold standard. Results A total of 48 cases of patients with achalasia, including 21 men and 27 women (mean age, 48.4 ± 19.6 years), were included in the study. Two patients were excluded. Of the remaining 46 patients, 36 (78.3%) patients were diagnosed as having achalasia by esophagography. The diagnostic sensitivity, specificity, and accuracy of esophagography were 78.3%, 88.0%, and 83.0%, respectively. Patients with type III achalasia had significantly lower physical QOL score than those with type I or II achalasia. Although the mental QOL score in patients with type III achalasia tended to decrease compared with that in patients with type I and II achalasia, the difference was not statistically significant. Conclusions Diagnosing esophageal achalasia by using esophagography alone has limited yield. Therefore, HREM should be used in patients with dysphagia and in whom achalasia cannot be diagnosed using EGD or esophagography. (J Neurogastroenterol Motil 2018;24:403-409)

      • KCI등재

        Biomechanical Analysis of a Pedicle Screw-Rod System with a Novel Cross-Link Configuration

        Yasuhiro Nakajima,Masahito Hara,Daisuke Umebayashi,Shoichi Haimoto,Yu Yamamoto,Yusuke Nishimura,Toshihiko Wakabayashi 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.6

        Study Design: The strength effects of a pedicle screw-rod system supplemented with a novel cross-link configuration were biomechanically evaluated in porcine spines. Purpose: To assess the biomechanical differences between a conventional cross-link pedicle screw-rod system versus a novel crosslink instrumentation, and to determine the effect of the cross-links. Overview of Literature: Transverse cross-link systems affect torsional rigidity, but are thought to have little impact on the sagittal motion of spinal constructs. We tested the strength effects in pullout and flexion-compression tests of novel cross-link pedicle screw constructs using porcine thoracic and lumbar vertebrae. Methods: Five matched thoracic and lumbar vertebral segments from 15 porcine spines were instrumented with 5.0-mm pedicle screws, which were then connected with 6.0-mm rods after partial corpectomy in the middle vertebral body. The forces required for construct failure in pullout and flexion-compression tests were examined in a randomized manner for three different cross-link configurations: un-cross-link control, conventional cross-link, and cross-link passing through the base of the spinous process. Statistical comparisons of strength data were analyzed using Student’s t -tests. Results: The spinous process group required a significantly greater pullout force for construct failure than the control group (p =0.036). No difference was found between the control and cross-link groups, or the cross-link and spinous process groups in pullout testing. In flexion-compression testing, the spinous processes group required significantly greater forces for construct failure than the control and cross-link groups (p <0.001 and p =0.003, respectively). However, there was no difference between the control and cross-link groups. Conclusions: A novel cross-link configuration that features cross-link devices passing through the base of the spinous processes increased the mechanical resistance in pullout and flexion-compression testing compared to un-cross-link constructs. This configuration provided more resistance to middle-column damage under flexion-compression testing than conventional cross-link configuration.

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