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991.
Yasuhiro Chihara Ayako Sato Michiteru Ohtani Chisato Fujimoto Takahiro Hayashi Hironobu Nishijima Masato Yagi Shinichi Iwasaki 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,231(3):257-266
First-generation H1-antihistamines are known to cause fatigue and drowsiness, due to their poor receptor selectivity and their high penetration rate of the blood–brain barrier. However, little is known about the effects of first-generation H1-antihistamines on postural stability. The purpose of this study was to evaluate the effects of d-chlorpheniramine on postural stability using posturography with and without foam rubber. A double-blind study with three parallel groups was conducted. Twenty-seven healthy young volunteers (mean age 21.9 years) were recruited and orally administered d-chlorpheniramine, 2 or 4 mg, or placebo. Postural sway was measured every hour up to 8 h after administration. Two-legged stance tasks were performed by each subject in four conditions: eyes open or eyes closed and with or without foam rubber. Inter-group comparisons showed that the group receiving 4-mg d-chlorpheniramine showed significantly larger sway in the eyes open with foam rubber condition (visual and vestibular information available, somatosensory information reduced). Inter-subject analysis in the 4-mg d-chlorpheniramine group showed that the effect of d-chlorpheniramine on postural control was variable. Our results suggest that among the three main sensory systems responsible for postural control (visual, vestibular, and somatosensory), d-chlorpheniramine may have a larger effect on the visual and/or vestibular systems in susceptible individuals. 相似文献
992.
Nobuaki Mizuguchi Izumi Umehara Hiroki Nakata Kazuyuki Kanosue 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,230(2):243-249
Motor imagery is defined as the mental execution of a movement without any muscle activity. In the present study, corticospinal excitability was assessed by motor evoked potentials (MEPs) when the subjects imagined isometric elbow flexion at various force levels. Electromyography was recorded from the right brachioradialis, the biceps brachii and the triceps brachii muscles. First, the maximum voluntary contraction (MVC) of elbow flexion was recorded in each subject. Subjects practiced performing 10, 30 and 60 % MVC using visual feedback. After the practice, MEPs were recorded during the imagery of elbow flexion with the forces of 10, 30 and 60 % MVC without any feedback. After the MEPs recording, we assigned subjects to reproduce the actual elbow flexion force at 10, 30 and 60 % MVC. The MEPs amplitudes in the brachioradialis and biceps brachii in the 60 % MVC condition were significantly greater than those in the 10 % MVC condition (p < 0.05). These findings suggest that the enhancement of corticospinal excitability during motor imagery is associated with an increase in imagined force level. 相似文献
993.
Kentaro Tokutomi Takashi Matsuura Phimon Atsawasuwan Hironobu Sato Mitsuo Yamauchi 《Connective tissue research》2013,54(5):361-366
At present, little is known about the age-related changes in jaw bones. The aim of this study was to characterize the mandibles of 6 month-old senile osteoporotic mice, SAMP6, and compare with those of age-matched controls, SAMR1. In comparison to SAMR1, SAMP6 showed thinner cortical bone, lower bone volume, and poorly organized collagen matrix. The collagen fibril diameter in SAMP6 was significantly smaller than that of SAMR1. In SAMP6 both collagen content and cross-links were lower than those of SAMR1, but the ratio of the major mature cross-link (pyridinoline) to its precursor reducible cross-link (dehydrodihydroxylysinonorleucine/its ketoamine) was higher in comparison to SAMR1. In addition, the extent of lysine hydroxylation of collagen was higher in SAMP6 than that of SAMR1. These results indicate that not only the quantity of collagen but also its quality are altered in SAMP6 and may result in the age-associated osteoporotic defects of mandibles. 相似文献
994.
Objective : The purpose of this study is to construct the cross-sectional head circumference growth curves, intended for clinical use, for the Japanese from birth to 18 years of age. Subjects and methods : Two sets of the national survey data on head circumference and height were utilized for the study: (1) The 1990 data collected by the Japanese Ministry of Health and Welfare on children below 7 years of age ( n = 16 621, 8511 males, 8110 females). (2) The 1992-1994 data collected by the Research Institute of Human Engineering for Quality Life on children from 7 to 18 years of age ( n = 10 183, 5610 males, 4573 females). We used the LMS method to obtain the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentile values for each age and gender. Results and conclusions : The results showed a persistent positive secular trend in head circumference in Japanese children of both genders. Comparison of these data with those of recent Caucasian studies revealed ethnic difference in head circumference, with Japanese having relatively larger head circumference for height as compared with Caucasians. 相似文献
995.
Junya Kaneko Takashi Tagami Chie Tanaka Kentaro Kuwamoto Shin Sato Ami Shibata Saori Kudo Akiko Kitahashi Masamune Kuno Shoji Yokobori Kyoko Unemoto 《Journal of stroke and cerebrovascular diseases》2021,30(8):105926
ObjectiveRebleeding of aneurysmal subarachnoid hemorrhage (aSAH) is one of the significant risk factors for poor clinical outcome. The rebleeding risk is the highest during the acute phase with an approximate rebleeding rate of 9-17% within the first 24 h. Theoretically, general anesthesia can stabilize a patient's vital signs; however, its effectiveness as initial management for preventing post-aSAH rebleeding remains unclear. The purpose of this study was to determine the feasibility and safety of ultra-early general anesthesia induction for reducing the rebleeding rates among patients with aSAH.Materials and methodsWe retrospectively evaluated patients with aSAH who were admitted to our department between January 2013 and December 2019. All the patients underwent ultra-early general anesthesia induction as initial management regardless of their severity. We evaluated the rebleeding rate before definitive treatment, factors influencing rebleeding, and general anesthesia complications.ResultsWe included 191 patients with two-third of them having a poor clinical grade (World Federation of Neurological Society [WFNS] grade IV or V). The median duration from admission to general anesthesia induction was 22 min. Rebleeding before definitive treatment occurred in nine patients (4.7%). There were significant differences in the Glasgow Coma Scale score (p = 0.047), WFNS grade (p = 0.02), and dissecting aneurysm (p <0.001) between the rebleeding and non-rebleeding patients. There were no cases of unsuccessful tracheal intubation or rebleeding during general anesthesia induction.ConclusionUltra-early general anesthesia induction could be performed safely in patients with aSAH, regardless of the WFNS grade; moreover, it resulted in lower rebleeding rate than that reported in previous epidemiological reports. 相似文献
996.
Kazuhiko Sato Takahiro Shimo Hiromi Fuchikami Naoko Takeda Masahiro Kato Tomohiko Okawa 《Brachytherapy》2021,20(1):163-170
PurposeMulticatheter interstitial brachytherapy (MIB) and external-beam (EB) radiotherapy are established partial-breast irradiation (PBI) techniques. Although EB-PBI is widely available, it requires extra irradiated margins for target uncertainties. We examined the impact of EB-PBI on dose–volume constraints as compared to MIB-PBI.Methods and MaterialsAmong 653 patients receiving MIB-PBI between October 2008 and April 2020, consequent 159 patients after September 2018 were examined. Clinical target volume (CTV) included the lumpectomy cavity plus 1.0 cm. Planning target volume (PTV) for EB-PBI was defined as CTV with 1.0-cm expansion. Because the ratio of PTV to breast volume (RPB) was related to cosmesis, <25% of RPB was defined as suitable for the ipsilateral breast constraints. Preoperative breast size was classified as very small (<350 cm3), small (350–699 cm3), and medium or large (≥700 cm3). According to each category, the dose–volume constraints of the organs at risk were compared between the two PBI techniques.ResultsPatients including 84 very small, 59 small, and 16 moderate to large breasts were examined. Although RPB was suitable in all patients receiving MIB-PBI, it was achieved in 74 patients (46.5%) receiving EB-PBI (p < 0.0001). The suitable RPB in patients with very small, small, and moderate to large breast was 32.1%, 55.9%, and 100%, respectively (p < 0.0001). Normal-tissue constraints for the other organs could be satisfied in patients with moderate to large breasts.ConclusionAlthough EB-PBI may be an appropriate option for patients with moderate to large breasts, MIB-PBI could still be a crucial technique, especially for patients with small breasts. 相似文献
997.
Bikei Ryu Shinsuke Sato Tatsuki Mochizuki Yasunari Niimi 《Journal of cerebral blood flow and metabolism》2021,41(6):1428
Asymptomatic dural arteriovenous fistulas (DAVFs) with cortical venous reflux (CVR) are now more commonly encountered. However, patients with an incidental onset may have a less aggressive clinical course. It is desirable to explore methods and indicators to predict the clinical outcomes. This study investigates whether the relative signal intensity (rSI) of the draining vessels on the time-of-flight magnetic resonance angiography is related to clinical behavior in patients with intracranial DAVFs. We retrospectively reviewed 36 intracranial DAVFs. The patients were categorized as those with either aggressive-presentation or non-aggressive-presentation (n = 16 and 20, respectively). The rSIs of the shunt points, affected sinuses, and veins with CVR were compared between the two groups. The two groups were not significantly different in terms of rSIs of the shunt points and affected sinuses (p = 0.37 and 0.41, respectively). However, a significant positive correlation was observed in the rSI of the veins with CVR between the aggressive and non-aggressive behavior groups (p < 0.0001). The rSI of the veins with CVR could serve as a reliable indicator of aggressive behavior in intracranial DAVFs, and its optimal cutoff value was 1.63 with high sensitivity and specificity for predicting aggressive behavior (area under the curve, 0.909). 相似文献
998.
999.
1000.
Daisuke Mori Michiaki Akashi Koichi Baba Kiyoto Morito Masami Shibaki Michinori Hashimoto Akashi Nakamura Seiko Mawatari Seiji Sato 《Pathology, research and practice》2013
A case of gastric undifferentiated carcinoma with diffuse c-kit overexpression and focal neuroendocrine differentiation is described. A 76-year-old man presented appetite loss for 1 month. Gastric endoscopy showed an exophytic huge nodular mass with central ulceration at the gastric prepylorus. Distal gastrectomy was performed with lymph node dissection. Histology indicated anaplastic medium- to large-sized round tumor cells in discohesive sheets. Adenocarcinomatous areas forming tubular glands or with intracytoplasmic mucin on PAS and Alcian-blue staining were not found in any sections. Immunohistochemistry showed that the tumor cells were diffusely positive for cytokeratin, vimentin, c-kit and focally positive for chromogranin A and synaptophysin. 相似文献