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41.
42.
Yoshitake Hayashi Yekti W. Widjono Kyosuke Ohta Keisuke Hanioka Chiho Obayashi Kyoko Itoh Yukihiro Imai Hiroshi Itoh 《Pathology international》1994,44(2):124-130
Immunohistochemical studies were performed to clarify the significance of the expression or overexpression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v- erb B, ras p21 in 23 cases each of tubular adenoma and adenocarcinoma. The expression of EGF, EGFR, p53, v- erb B, and ras p21 in paraffin-embedded tissues, from 46 patients with colorectal tumors (adenoma: 23 cases; 14 mild dysplasia, six moderate dysplasia, three severe dysplasia, adenocarcinoma: 23 cases; 17 well differentiated, two moderately differentiated, three poorly differentiated, one mucinous carcinoma was analyzed immunohistochemically using anti-EGF, EGFR, p53, v- erb B and ras p21 antibodies. The EGF and ras p21 tended to express more strongly in carcinoma cases than in the adenoma cases, and in severe and moderate dysplasia than in mild dysplasia (EGF: stained positive in five adenomas [21.74%] and 17 adenocarcinomas [73.91%]; ras p21: stained positive in six adenomas [26.09%] and 14 adenocarcinomas [60.87%]. The EGFR stained positive in two adenomas (8.70%) and two adenocarcinomas (8.70%). The p53 and v- erb B showed positive staining only in the carcinoma cases (p53: stained positive in four cases [17.39%]; v- erb B: stained positive in eight cases [34.78%]). This study suggests that these factors seem to have some role in the progression of colon neoplasms. It suggests that genetic alteration is not always equal to the overexpression of protein products, but that it reflects them well, and that the staining makes some contribution to differential diagnosis in colorectal neoplasms. 相似文献
43.
44.
Seung Yong Park Hisashi Arase Keisuke Wakizaka Nakami Hirayama Shigehiro Masaki So-Ichiro Sato Jeffrey V. Ravetch Takashi Saito 《European journal of immunology》1995,25(7):2107-2110
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia. 相似文献
45.
Mice lacking smooth muscle calponin display increased bone formation that is associated with enhancement of bone morphogenetic protein responses 总被引:5,自引:0,他引:5
46.
Diagnostic utility of galectin-3 and CD26/DPPIV as preoperative diagnostic markers for thyroid nodules 总被引:3,自引:0,他引:3
Aratake Y Umeki K Kiyoyama K Hinoura Y Sato S Ohno A Kuribayashi T Hirai K Nabeshima K Kotani T 《Diagnostic cytopathology》2002,26(6):366-372
The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis. 相似文献
47.
Kushiro K Dai M Kunin M Yakushin SB Cohen B Raphan T 《Journal of neurophysiology》2002,88(5):2445-2462
Nystagmus induced by off-vertical axis rotation (OVAR) about a head yaw axis is composed of a yaw bias velocity and modulations in eye position and velocity as the head changes orientation relative to gravity. The bias velocity is dependent on the tilt of the rotational axis relative to gravity and angular head velocity. For axis tilts <15 degrees, bias velocities increased monotonically with increases in the magnitude of the projected gravity vector onto the horizontal plane of the head. For tilts of 15-90 degrees, bias velocity was independent of tilt angle, increasing linearly as a function of head velocity with gains of 0.7-0.8, up to the saturation level of velocity storage. Asymmetries in OVAR bias velocity and asymmetries in the dominant time constant of the angular vestibuloocular reflex (aVOR) covaried and both were reduced by administration of baclofen, a GABA(B) agonist. Modulations in pitch and roll eye positions were in phase with nose-down and side-down head positions, respectively. Changes in roll eye position were produced mainly by slow movements, whereas vertical eye position changes were characterized by slow eye movements and saccades. Oscillations in vertical and roll eye velocities led their respective position changes by approximately 90 degrees, close to an ideal differentiation, suggesting that these modulations were due to activation of the orienting component of the linear vestibuloocular reflex (lVOR). The beating field of the horizontal nystagmus shifted the eyes 6.3 degrees /g toward gravity in side down position, similar to the deviations observed during static roll tilt (7.0 degrees /g). This demonstrates that the eyes also orient to gravity in yaw. Phases of horizontal eye velocity clustered ~180 degrees relative to the modulation in beating field and were not simply differentiations of changes in eye position. Contributions of orientating and compensatory components of the lVOR to the modulation of eye position and velocity were modeled using three components: a novel direct otolith-oculomotor orientation, orientation-based velocity modulation, and changes in velocity storage time constants with head position re gravity. Time constants were obtained from optokinetic after-nystagmus, a direct representation of velocity storage. When the orienting lVOR was combined with models of the compensatory lVOR and velocity estimator from sequential otolith activation to generate the bias component, the model accurately predicted eye position and velocity in three dimensions. These data support the postulates that OVAR generates compensatory eye velocity through activation of velocity storage and that oscillatory components arise predominantly through lVOR orientation mechanisms. 相似文献
48.
Exponential hyperbolic sine function fitting of heart rate response to constant load exercise 总被引:1,自引:0,他引:1
Mizuo J Nakatsu T Murakami T Kusachi S Tominaga Y Mashima K Uesugi T Ueda H Suezawa C Tsuji T 《The Japanese journal of physiology》2000,50(4):405-412
We attempted to fit heart rate (HR) changes induced by constant exercise loads of different intensities to an exponential hyperbolic sine curve by the least-squares method, and we compared the results with the fitting of the changes to exponential curves. Seven healthy male volunteers performed three different intensities of constant-load exercise on a bicycle ergometer. The exponential hyperbolic sine function adequately fitted the HR responses induced by all three different intensities of loads: low (30 W: correlation coefficient, r = 0.68 +/- 0.13, mean +/- SD), moderate (75 W: r = 0.93 +/- 0.07) and high (125 W: r = 0.97 +/- 0.02). The first-order exponential curve fitted only the moderate load response. Although the second-order exponential equation fitted the HR response for both the moderate and high loads, the equation did not fit the low-load response (r = 0.43 +/- 0.26). In low-load exercise, the sum of the power of the residuals for the exponential hyperbolic sine curve fitting was significantly smaller than that for the first- or second-order exponential curve fitting. In conclusion, the exponential hyperbolic sine function is useful for quantitative analyses of the HR response to exercise loads of various intensities. 相似文献
49.
Tatsuro Inoue Keisuke Maeda Ayano Nagano Akio Shimizu Junko Ueshima Kenta Murotani Keisuke Sato Kazuki Hotta Shinichiro Morishita Atsuhiro Tsubaki 《Nutrients》2021,13(2)
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future. 相似文献