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31.
Takehiko Ohzeki Keiichi Hanaki Nobuo Ishitani Hiroko Ohtahara Hirofumi Urashima Toshinori Tsukuda Jun-Ichi Nagaishi Kazuo Shiraki 《American journal of human biology》1995,7(2):237-240
Skinfold thicknessess (SFT) were measured at ulnar, triceps, subscapular and suprailiac sites in 730 boys and 724 girls (age 3–12 years) whose stature ranged from 100 to 150 cm and whose weight was within ±20% of the average. Means and standard deviation (SD) were calculated after logarithmic transformation of the original skinfold readings to demonstrate stature-based standards of SFT in Japanese children. The means of SFT exhibited nadirs (boys/ girls: ulnar 5.1/5.9 mm, triceps 7.9/9.5 mm, subscapular 4.9/6.1 mm, suprailiac 4.5/6.2 mm) in subjects 110–115 cm tall except for ulnar SFT in girls. SFT values increased as children increased in stature. Standard deviations of SFT at the four sites in short children (staturte < mean ?1 SD) were estimated using the stature-based standard as well as an age-based standard. Susms of the SDs assessed by the age-based standard were significantly smaller than those assessed by the stature-based standard in boys (P < 0.05) and girls (P < 0.01) with short stature, suggesting that SFT in short children was falsely understimated by the age-based standard. Thus, the stature-based standard is beneficial for the assessment of SFT, especially in children whose stature is below the mean ?-1 SD. © 1995 Wiley-Liss, Inc. 相似文献
32.
Shimamura K Zhou M Toba M Kimura S Higuchi T Kawaguchi H Sekiguchi F Sunano S 《Pflügers Archiv : European journal of physiology》2003,446(1):30-35
The effects of L-arginine on spontaneous contraction of endothelium-denuded longitudinal preparations of the rat portal vein were studied. L-arginine increased the frequency of spontaneous contraction concentration-dependently between 10 microM and 1 mM. Changes in contraction amplitude and duration were not remarkable. D-arginine had a negligible effect on spontaneous contraction. N(omega)-nitro-L-arginine (1 mM) did not affect spontaneous contraction or the response to L-arginine. Addition of N(G)-monomethyl-L-arginine (1 mM), l-lysine (1 mM) or N-ethymaleimide (0.1 mM) increased the frequency of spontaneous contractions and inhibited the effect of L-arginine. Glibenclamide (10 microM) did not affect spontaneous contraction or the response to L-arginine. Spontaneous increase in concentration of intracellular Ca2+, estimated as the ratio of Fura-PE3 fluorescence occurred synchronously with spontaneous contraction. Spontaneous increase in concentration of intracellular Ca2+ occurred more frequently in the presence of L-arginine (1 mM). L-arginine (1 mM) also increased the number of action potential bursts/min in the longitudinal smooth muscle layer. L-arginine (1 mM) also depolarized cell membranes. This study indicates that L-arginine increases the frequency of spontaneous contraction of longitudinal muscle in the rat portal vein by membrane depolarization through mechanisms that do not involve nitric oxide or the inhibition of ATP-sensitive K+ channels. 相似文献
33.
Akira Nakagawara Toshimitsu Toyohara Keiichi Ikeda Osami Nada Masazumi Tsuneyoshi 《Virchows Archiv : an international journal of pathology》1986,409(5):571-582
Summary The intratumorous distribution of catecholaminergic clone cells in 23 human neuroblastomas was studied using Falck-Hillarp's method, and the findings compared with the catecholamine (CA) content within the tumour. All the specimens contained elements with CA fluorescence, and the pattern of fluorescence was classified from the distribution of CA-positive cells and neurofibrils, as diffuse cellular (DC); diffuse fibrillary (DF), sporadic (S), clustered (C), island-shaped (I), and bundled (B). The strength of CA fluorescence of both cellular and fibrillary elements correlated well with the CA content within the tumour. In addition, all tumours of urinary VMA-negative cases also contained significantly larger amounts of CA than other, non-functioning, tumours in the paediatric age group. The results of this study suggest that firstly, the ratio of CA-positive cells to CA-positive neuronal processes is proportionately higher in the poorly-differentiated neuroblastomas and that secondly, even tumours negative for urinary VMA or HVA might be polyclonal and contain catecholaminergic elements.This study was supported in part by a Research Grant from the Ministry of Education, Japan (No. 59570549) 相似文献
34.
Tanaka K Tamura J Kawanabe K Nawa M Uchida M Kokubo T Nakamura T 《Journal of biomedical materials research. Part A》2003,67(1):200-207
Recently zirconia/alumina composites have been examined by many researchers as the new generation of bearing materials in total joint replacements. In this study, the phase stability of a Ce-TZP/Al(2)O(3) nanocomposite and conventional Y-TZP after aging, and its influence on wear resistance, were investigated. Very slight phase transformation was observed in both types of ceramics 18 months after the implantation of Ce-TZP/Al(2)O(3) or Y-TZP samples into rabbit tibiae. However, Y-TZP showed marked phase transformation (approximately 80%) after aging in an autoclave (121 degrees C) for 190 h or in physiological saline at 62 degrees C for 18 months, whereas the new composite remained almost resistant to degradation. According to the results of self-pairing pin-on-disk wear tests using ceramic specimens with or without autoclave aging, the wear factor was almost the same between Ce-TZP/Al(2)O(3) samples with and without aging (6.74 +/- 0.36 x 10(-8) and 6.04 +/- 0.95 x 10(-8) mm(3)/Nm, respectively). In contrast, although non-aged Y-TZP had the lowest wear factor (4.88 +/- 0.51 x 10(-8) mm(3)/Nm) of all specimens tested, aged Y-TZP showed 10-fold greater wear than nonaged Y-TZP. The present study suggests that Ce-TZP/Al(2)O(3) nanocomposite has much greater phase stability than Y-TZP, and that its wear properties are not influenced by aging. 相似文献
35.
Generators of visual evoked potentials for faces and eyes in the human brain as determined by dipole localization 总被引:4,自引:0,他引:4
Human visual evoked potentials were recorded during presentation of photos of human and animal faces and various face features. Negative waves with approximate peak latencies of 165 msec (N170) were bilaterally recorded from the occipito-temporal regions. Mean peak latencies of the N170 were shorter for faces than eyes only. Analyses of amplitudes of evoked potentials indicated that the N170 elicited by faces reflected activity of a specific neural system which was insensitive to detailed differences among individual faces regardless of species, and consequently suggest that this system might function to detect existence of faces in general. On the other hand, the mean amplitude of the N170 elicited by human eyes was significantly larger than those by animal eyes. These differences in response latencies and amplitudes of the N170 suggest existence of at least 2 different visual evoked potentials with similar latencies (i.e., N170) which are sensitive to faces in general and human eyes, respectively. Dipole source localization analysis indicated that dipoles for the N170 elicited by eyes were located in the posterior inferior temporal gyrus, and those for faces, located initially in the same region, but moved toward the fusiform and lingual gyri at the late phase of the N170. The results indicated that information processing of faces and eyes separated at least as early as the latency of the N170 at the posterior inferior temporal gyrus as well as the fusiform and lingual gyri, and might provide neurophysiological and anatomical bases to an initial structural encoding stage of human faces. 相似文献
36.
Keiichi Kimura Yoshiaki Inaki Kiichi Takemoto 《Macromolecular chemistry and physics.》1977,178(2):317-328
The initiation mechanism of vinyl polymerization by a copper(II) chelate of poly(vinyl alcohol) was studied in aqueous solution in the presence of carbon tetrachloride, in order to determine the free radical species formed during the initiation step. Trichloromethyl radicals were ascertained to be the main initiation species, by spin trapping and gelation experiments. Differences in polymerization activity between methyl methacrylate and acrylonitrile are discussed. 相似文献
37.
Masanori Hosokawa Ryuichi Kasai Keiichi Higuchi Shuji Takeshita Katsuji Shimizu Hajime Hamamoto Atsuko Honma Mika Irino Kayoko Toda Atsuko Matsumura Mutsumi Matsushita Toshio Takeda 《Mechanisms of ageing and development》1984,26(1):91-102
For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in 相似文献
38.
Saruta J Tsukinoki K Sasaguri K Ishii H Yasuda M Osamura YR Watanabe Y Sato S 《Cells, tissues, organs》2005,180(4):237-244
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva. 相似文献
39.
Kawakita M Hiramatsu K Sugimoto M Takahashi K Toi M 《Rinsho byori. The Japanese journal of clinical pathology》2004,52(4):321-327
N1,N12-Diacetylspermine(DiAcSpm) and N1,N8-diacetylspermidine(DiAcSpd) are excreted in the urine of healthy persons as minor components of urinary polyamine, with small individual variations in amount. They are promising tumor markers, since their excretion is frequently elevated in patients with various types of cancers. DiAcSpm is sensitive in cancer detection, while DiAcSpd is highly specific for cancer. Diacetylpolyamines were initially characterized and determined by HPLC fractionation, followed by enzymatic detection. More recently, antibodies highly specific for DiAcSpm and DiAcSpd were developed, and an ELISA system applicable to the determination of urinary DiAcSpm was established. Measurement of urinary DiAcSpm using this ELISA system revealed that DiAcSpm is a more sensitive tumor marker than CEA, CA19-9 and CA15-3 for colon and breast cancers. More importantly, DiAcSpm efficiently detects patients at early stages. On the other hand, CEA, CA19-9 and CA15-3 are quite insensitive for early stage cancers. The urinary DiAcSpm level tends to remain low even in tumor-bearing individuals when their cancerous lesions remain static, while it rises rapidly concomitant with recurrence. DiAcSpm may serve as a prognostic indicator and marker for recurrence of prostate and colon cancers. Diacetylpolyamines may turn out to be general tumor markers, since active proliferation of any cancer tissues would likely be accompanied by activation of polyamine metabolism. 相似文献
40.
Hiroshi Suemizu Yutaka Tsutsumi Keiichi Watanabe Masahide Kuroki Yuji Matsuoka 《Pathology international》1989,39(12):772-778
Nonspecific cross reacting antigen (NCA), a constituent of the carcinoembryonic antigen family, was localized ultra-structurally in a human lung adenocarcinoma cell line, PC 9. NCA was distributed predominantly on the plasma membrane in the early phases of cell culture. Deletion of fetal bovine serum (FBS) from the culture medium suppressed cell division without significantly altering cell viability, and induced a dramatic but reversible change in NCA localization. Under these conditions, NCA was localized to membrane degradation products within cytoplasmic vesicles and vacuoles. Acid phosphatase activity was also present in some of these intracellular structures. Similar changes in NCA localization were seen in cells cultured with FBS at day 6 when the cells reached a plateau stage of growth. These findings strongly suggest that plasma membrane degradation is accelerated by the cessation of cell growth. Cytoplasmic reactivity for NCA in cancer cells may therefore reflect degradation of plasma membrane-associated NCA and may not necessarily be correlated with increased systhesis of this glycoprotein. Acta Pathol Jpn 39: 772 778, 1989. 相似文献