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61.
Palmar advancement flap with V-Y closure for thumb tip injuries 总被引:1,自引:0,他引:1
Hwang-hyun Bang MD Tadao Kojima MD Hiroyuki Hayashi MD 《The Journal of hand surgery》1992,17(5):933-934
The palmar advancement flap with V-Y closure was used in two patients with thumb tip injuries. This technique allows more distal advancement of the flap than does a conventional palmar advancement flap and does not require skin graft coverage. 相似文献
62.
STUDY OBJECTIVE--The aim was to clarify the inhibitory effect of the selective kappa agonist, spiradoline, on coronary arterial smooth muscle in relation to the intracellular Ca2+ concentration. DESIGN--The inhibitory effect of spiradoline was investigated (1) on the contractile response of pig coronary artery to the readmission of Ca2+, following initial exposure to Ca2+ free medium and depolarisation with 40 mM K+; (2) on the intracellular Ca2+ concentration as assessed using the fluorescent calcium indicator fura-2. Relaxant responses to spiradoline in isolated porcine coronary artery strips contracted with K+ and prostaglandin F2 alpha were also examined. EXPERIMENTAL MATERIAL--Coronary arteries isolated from pigs of both sexes were used. The right and left circumflex coronary arteries were cut into 3 mm wide strips which were used to measure the change in contractile force and the intracellular Ca2+ concentration. MEASUREMENTS AND MAIN RESULTS--Prior treatment with spiradoline at 2 x 10(-6) mol.litre-1 or more inhibited the contractile response to the readmission of Ca2+ in porcine coronary artery exposed to Ca2+ free medium in the presence of high K+. Naloxone at 3 x 10(-4) mol.litre-1 did not reverse the inhibitory action of 2 x 10(-5) M spiradoline. Ca2+ induced contraction was inhibited completely by 10(-4) M spiradoline. Moreover, spiradoline caused relaxation in arterial preparations that had been contracted with K+ (15 to 25 mmol.litre-1) or prostaglandin F2 alpha (10(-6) to 3 x 10(-6) mol litre-1), greater relaxation being seen in the K+ induced contraction. The intracellular Ca2+ concentration was significantly lowered by 2 x 10(-5) M spiradoline. CONCLUSIONS--The relaxant response of coronary artery to spiradoline is, in part, attributable to interference with Ca2+ entry into the arterial smooth muscle. 相似文献
63.
Atsutoshi Ina Ken-Ichiro Hayashi Hiroshi Nozaki Yuto Kamei 《International journal of developmental neuroscience》2007,25(1):63-68
We identified and characterized a neurodifferentiation compound from the marine brown alga Sargassum fulvellum collected from the Japanese coastline. Several instrumental analyses revealed the compound to be pheophytin a. Pheophytin a did not itself promote neurite outgrowth of PC12 cells. However, when PC12 cells were treated with a low concentration of pheophytin a (3.9 microg/ml) in the presence of a low level of nerve growth factor (10 ng/ml), the compound produced neurite outgrowth similar to that produced by a high level of nerve growth factor (50 ng/ml). Pheophytin a also enhanced signal transduction in the mitogen-activated protein kinase signaling pathway, which is also induced by nerve growth factor. The effect of pheophytin a on neurite outgrowth of PC12 cells was completely blocked by U0126, a representative mitogen-activated protein kinase kinase inhibitor. These results suggest that pheophytin a enhances the neurodifferentiation of PC12 cells in the presence of a low level of nerve growth factor and that this effect is mediated by activation of a mitogen-activated protein kinase signaling pathway. 相似文献
64.
Purification and characterization of human immunodeficiency virus type 1 nef gene product expressed by a recombinant baculovirus 总被引:5,自引:0,他引:5
Y Matsuura M Maekawa S Hattori N Ikegami A Hayashi S Yamazaki C Morita Y Takebe 《Virology》1991,184(2):580-586
We have constructed the recombinant baculovirus which expresses the human immunodeficiency virus type 1 negative factor (nef) gene. Spodoptera frugiperda cells infected with the recombinant virus produced a 27-kDa protein which reacted with rabbit antisera raised against a carboxy-terminal synthetic peptide of the Nef protein by immunoblot analysis. Labeling experiment showed that the recombinant Nef protein was myristoylated. The recombinant Nef protein was purified to near homogeneity by DEAE-Sephacel, phenyl-Sepharose 4B, blue-Sepharose, and Sephadex G-150 column chromatography. No detectable GTP binding activity was observed in the purified recombinant Nef product. 相似文献
65.
66.
67.
在免眼中进行经瞳孔阈值下温热疗法的组织学效应和蛋白表达 总被引:1,自引:0,他引:1
Yoshihiro Morimura Annabelle A. Okada Atsushi Hayashi Sayuri Fujioka Sumie Kawahara Tetsuo Hida 李扬 《美国医学会眼科杂志(中文版)》2005,17(3):185-186
目的:研究阈值下经瞳孔温热疗法(TTT)对视网膜组织学的效应。方法:对正常视网膜色素的兔眼进行TTT,通过1个810nm激光二极管产生直径为1.2mm能量为50mW的光斑,持续时间为15、30和60秒。4周后进行荧光血管造影并摘除眼球,通过电子显微镜和免疫组化染色来检查。 相似文献
68.
T Urakawa Y Nagahata S Fukuoka T Hayashi T Takata S Matsui M Nakamoto Y Hirai K Kumagai Y Saitoh 《Nihon Geka Gakkai zasshi》1986,87(2):180-188
We prepared obstructive jaundice models in rats in order to study the mechanism of acute ulceration in obstructive jaundice centering on impediments to gastric wall blood flow and changes in gastric mucosal NA and PGE2 when the rats were subjected to water immersion restraint stress. The results were: In the obstructive jaundice 2 weeks group, when subjected to water immersion restraint stress, gastric mucosal NA reached a dried up stage from the incipient stage, causing gastric mucosal impediments at the same time, showing a significant decrease of gastric mucosal PGE2. Intragastric pH was at a similar level of excessive acidity in all groups; gastric acid is believed to be a secondary factor promoting ulceration. Gastric mucosal PGE2 showed a significant decrease coinciding with the increase in ulceration index, being a possible factor of ulceration; it is also presumed to regulate gastric wall blood flow alternatively with gastric mucosal NA. Pre-treatment with PGE2 prior to loading stress resulted in a decrease in gastric wall blood flow being significantly controlled. The administration of PGE2 brought about an improvement in gastric wall blood flow and a consequent increase in gastric mucosal NA, being judged effective for acute ulceration in obstructive jaundice. 相似文献
69.
S Ueno R Ootsuka Y Hayashi H Nishitani N Shirakawa T Hashimoto 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》1992,52(10):1417-1423
Intracranial MR imaging was performed in five patients with achondroplasia. All patients had narrowing of the subarachnoid space at the level of the foramen magnum that was mainly due to protrusion of the posterior aspect. Three patients had compressive deformities of the brainstem and/or upper cervical spine. Among them, two patients had deformities of the pons. Relative upward displacement of the brainstem was seen in all patients. Hydrocephalus was seen in three patients. 相似文献
70.
M. Ito T. F. Lang M. Jergas M. Ohki M. Takada T. Nakamura K. Hayashi H. K. Genant 《Calcified tissue international》1997,61(2):123-128
This study examined trabecular bone mineral density (BMD) in Japanese women with and without spinal fracture, and compared
the results to American women with and without fracture. The quantitative computed tomography (QCT) systems used at the University
of California, San Francisco (UCSF) and at Nagasaki University were cross-calibrated. Normative BMD was assessed with the
K2HPO4 liquid phantom in 538 Americans aged 20–85 years, and with the B-MAS200 phantom in 577 Japanese aged 20–83 years. These BMD
were adjusted for use with the Image Analysis solid phantom using the result of cross-calibration. The trabecular BMD in 111
postmenopausal American women (55 with fracture), and in 185 postmenopausal Japanese women (67 with fracture) were compared
for investigation of the difference in BMD values relative to fracture status. The absolute BMD values in Japanese were lower
than those in Americans, and the differences were greater with advancing age. The magnitude of the BMD difference was 8.6,
20.5, 38.1 mg/cm3 in women aged 20–24 years, 40–44 years, 60–64 years, respectively. In premenopausal women, BMD began to decrease at the age
of 20 in Japanese, whereas the peak bone mass was maintained until the age of 35 in the American women. In immediate postmenopausal
women, BMD significantly decreased in both populations. In later postmenopausal women, BMD significantly decreased with age
in the Japanese women but decreased less rapidly in the American women. The aging decrease of BMD was 1.4% and 2.2% per year
in the later postmenopausal American and Japanese women, respectively. The fracture threshold is considered to be lower in
Japanese women. However, the BMD difference between American and Japanese women with fracture was similar to that without
fracture. The Z-scores of fracture subjects versus controls were 2.9 in American and 1.8 in Japanese women. In conclusion,
Japanese women were found to have a lower BMD and lower fracture threshold than American women. The significant decrease of
spinal trabecular BMD in late postmenopause is potentially responsible for the higher prevalence of spinal fracture in Japanese
women.
Received: 18 December 1995 / Accepted: 23 September 1996 相似文献