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31.
Haruo Sagaza 《Geriatrics & Gerontology International》2004,4(S1):S34-S37
Recently the term 'global aging', which refers to the universal trend of aging of the world population, is being widely used. First of all, I will shed some light on this trend of world population aging from the viewpoint of regional populations and their future projections.
Second, I will discuss about the determinants of population aging in the Asia and Oceania region. So far as the region is concerned, it will be divided into three groups of countries according to the level of population aging. The first group is the most advanced aged countries such as Japan, Australia, and New Zealand whose percentage of the elderly aged 65 and over is more than 10% in the year of 2000. The second group is the aging countries such as Korea, Taiwan, Singapore, and China whose percentage of the elderly is between 5 and 10%. and the third group is the remaining countries in this region whose percentage is less than 5%. The demographic aspects of each group are analyzed and the relationships between the fertility reduction and aging are also discussed in the perspectives of the demographic transition.
Third, I will discuss about the consequences of population aging in this region with special reference to Asian developing countries. In this section, I will mention the problems of dependency burden, the so-called population bonus, health expectancy, and social security systems. Fourth, some prominent characteristics concerning the living conditions and norms or attitudes of the elderly will be indicated, and I will also raise such points like family systems, living arrangements, social participation, and Ikigai (the worth of life) peculiar to Asian countries. Fifth and finally, I will touch on the topics of the issues and policies of the aging society. At present the social status of the elderly is improving in Asian countries and it is in the hope that the myth of aging will disappear in the near future. 相似文献
Second, I will discuss about the determinants of population aging in the Asia and Oceania region. So far as the region is concerned, it will be divided into three groups of countries according to the level of population aging. The first group is the most advanced aged countries such as Japan, Australia, and New Zealand whose percentage of the elderly aged 65 and over is more than 10% in the year of 2000. The second group is the aging countries such as Korea, Taiwan, Singapore, and China whose percentage of the elderly is between 5 and 10%. and the third group is the remaining countries in this region whose percentage is less than 5%. The demographic aspects of each group are analyzed and the relationships between the fertility reduction and aging are also discussed in the perspectives of the demographic transition.
Third, I will discuss about the consequences of population aging in this region with special reference to Asian developing countries. In this section, I will mention the problems of dependency burden, the so-called population bonus, health expectancy, and social security systems. Fourth, some prominent characteristics concerning the living conditions and norms or attitudes of the elderly will be indicated, and I will also raise such points like family systems, living arrangements, social participation, and Ikigai (the worth of life) peculiar to Asian countries. Fifth and finally, I will touch on the topics of the issues and policies of the aging society. At present the social status of the elderly is improving in Asian countries and it is in the hope that the myth of aging will disappear in the near future. 相似文献
32.
大肠癌旁粘膜细胞的PCNA和AgNORs表达观察 总被引:2,自引:0,他引:2
用增殖细胞核抗原(PCNA)和核仁组成区嗜银蛋白(AgNORs)对35例大肠癌旁粘膜进行细胞增殖表达与观察。结果表明:癌旁粘膜的PCNA标记指数增多,标记增强,排列紊乱。AgNORs在癌旁粘膜中,颗粒增多、增大,形态多样,0 ̄1cm和2 ̄3cm组的标记指数与4 ̄5cm组的标记指数相比较,有显著或非常显著差异(P〈0.05或P〈0.01)。在DukeA、B期中,细胞标记指数增高增强,与癌的发生和患者 相似文献
33.
Alpha and gamma motoneurons in the peroneal nuclei of the cat spinal cord: an ultrastructural study.
J Destombes G Horcholle-Bossavit D Thiesson L Jami 《The Journal of comparative neurology》1992,317(1):79-90
The aim of the present study was to investigate whether ultrastructural features can be used as a guide to identify alpha- and gamma-motoneurons among the intermediate-size neurons of the peroneal motor nuclei. The peroneus brevis and peroneus tertius muscles of adult cats were injected with horseradish peroxidase, and motoneurons labeled by retrograde axonal transport were examined by electron microscopy. In both nuclei, the distributions of cell-body diameters, measured in the light microscope, were bimodal covering the range of 28-84 microns, with a trough around 50 microns. The sample of 25 motoneurons selected for the ultrastructural study included not only large (presumed alpha) and small (presumed gamma) neurons but also intermediate-size cell bodies with diameters in the 40-60 microns range. For each motoneuron, 2-5 profiles were reconstructed from ultrathin sections taken at 6-8 microns intervals. Synaptic boutons were counted and their lengths of apposition were measured. On the basis of three criteria, namely: (1) bouton types present on the membrane, (2) percentage of membrane length covered by synapses, and (3) the aspect of the nucleolus, all the examined motoneurons, including those with intermediate sizes, fell into one of two categories. Fourteen motoneurons, with cell-body diameters in a range of 55-84 microns, were contacted by all types of boutons (mainly S-type with spherical vesicles, F-type with flattened vesicles, and C-type with subsynaptic cistern); the synaptic covering of the somatic membrane was over 40% and the nucleus contained a vacuolated nucleolus. These were considered alpha-motoneurons. Eleven motoneurons, with only S and F boutons, a synaptic covering under 30%, a compact nucleolus and a cell-body diameter ranging between 28 and 50 microns, were considered gamma-motoneurons. No other combination of the three criteria was observed. These results show that unequivocal distinction of alpha- and gamma-motoneurons is possible in the peroneal nuclei, on the basis of morphological differences independent of cell-body size. 相似文献
34.
J. H. Vos T. S. G. A. M. van den Ingh F. C. S. Ramaekers M. De Neijs F. N. van Mil D. Ivanyi 《Anatomical record (Hoboken, N.J. : 2007)》1992,234(3):391-398
The intermediate filament labeling pattern of the epithelial structures of the canine anal region was studied with different polypeptide specific keratin monoclonal antibodies (MoAbs) and with a monoclonal and polyclonal vimentin antibody. The epithelial structures in this region could be discriminated and characterized by differences in their keratin staining pattern. The basal cells in the different epithelial structures showed a similar staining pattern characterized by reactivity with MoAbs staining keratins 5, 8, 14, and 17. Columnar epithelial cells showed a completely different phenotype mostly characterized by reactivity with MoAbs staining keratins 7, 5, 8, 18, and 19. A restricted number of differentiated perianal gland cells showed perinuclear vimentin staining. Myoepithelial cells did not stain for vimentin, but, as other basal cells, were positive for MoAbs staining keratins 5, 8, 14, and 17.© Willey-Liss, Inc. 相似文献
35.
The knee meniscus exhibits extensive spatial variations in native healing capacity, biochemical composition, and cell morphology that suggest the existence of distinct phenotypes for meniscus cells. Constitutive gene expression levels of appropriate extracellular matrix proteins may serve as useful molecular markers of cellular phenotypes; however, relatively little is known of variations in the gene expression for meniscus cells of different regions of the tissue. The objective of the present study was to evaluate constitutive differences between radial inner and outer regions in gene expression for extracellular matrix proteins relevant to the meniscus. A secondary objective was to determine if these region-specific differences in gene expression are maintained after periods of monolayer culture. The innermost regions of the meniscus were found to constitutively express higher mRNA levels for proteins highly expressed in articular cartilage, including aggrecan, type II collagen, and NOS2. In contrast, the outer meniscus was found to contain higher gene expression for proteins associated with fibrous tissues including type I collagen, and the proteases MMP2 and MMP3. Isolated inner and outer meniscus cells maintained these region-specific gene expression patterns for collagens and proteoglycans during short-term monolayer culture. The results provide new information that suggests the utility of constitutive gene expression levels as molecular markers to distinguish tissue and cells of the inner and outer meniscus. 相似文献
36.
We consider a class of Cohen–Grossberg neural networks with delays. We prove the existence and global asymptotic stability of an equilibrium point and estimate the region of existence. Furthermore, we show that the trajectories of the neural networks with positive initial data will stay in the positive region if the amplification function satisfies a divergent condition. We also establish the existence of a globally attracting compact set for more general networks. We estimate this compact set explicitly in terms of the network parameters from physiological and biological models. Our results can be applied to neural networks with a wide range of activation functions which are neither bounded nor globally Lipschitz continuous such as the Lotka–Volterra model. We also give some examples and simulations. 相似文献
37.
应用银染技术,对24例结肠腺癌Ⅱ级不典型增生,30例绒毛状腺瘤,14例绒毛状腺瘤Ⅲ级不典型增生和29例高分化管状腺癌进行银染核仁形成区嗜银蛋白(Ag-NORs)定量研究,观察Ag-NORs数量、形态、大小和分布在结肠肿瘤交界性病变中的表达.提示Ag-NORs四项指标定量研究对结肠脉瘤,特别是Ⅲ级不典型增生与绒毛状腺瘤之结肠癌前病变有较好的监测作用. 相似文献
38.
A mature cystic teratoma in pineal region mimicking parietal encephalocele in a newborn 总被引:1,自引:0,他引:1
M. Kemali Baykaner Ertan Ergun Berker Cemil Pelin Bayik Hakan Emmez 《Child's nervous system》2007,23(5):573-576
Objective Teratoma is the most frequently encountered intracranial tumor at birth and constitutes 18–20% of all germ cell tumors. They
are usually located in pineal and suprasellar regions. The authors aim to report an extremely unusual presentation, location,
and appearance of a teratoma in a newborn.
Case report A soft tissue swelling in the vertex was detected in a 1-month-old girl. Neurological examination was normal. A big, cystic–solid
lesion beginning from pineal region and extending to the scalp was detected in magnetic resonance imaging. It is interesting
to note that cerebral venous angiography showed that the superior sagittal sinus (SSS) was divided into three branches at
the level of the lesion and they joined together distally. The tumor was excised totally. Histopathological examination revealed
the diagnosis of a mature cystic teratoma.
Conclusion A mature cystic teratoma mimicking parietal encephalocele is extremely rare. Germ cell tumors should be kept in mind in the
differential diagnosis of all midline lesions with unusual radiographic appearance. Cerebral venous angiography or MR angiography
must be performed for the diagnosis and the surgical planning in lesions located near SSS. 相似文献
39.
In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells. 相似文献
40.
观察上颌窦鳞状细胞癌核仁组成区相关区相关嗜银蛋白的改变,方法:采用胶银染色法对26例上凳窦鳞状细胞癌进行AgNORs检测。 相似文献