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31.
It is hypothesized that a bird's-eye view affects children's thinking on the transition from route to configurational knowledge. Children were asked to make a cognitive map about the region where they live. Then each child was identified whether he had a bird's-eye view or not according to the small-scale space task (i.e., "apples on the table" task) and the large-scale space task (i.e., "a landscape" task). The results of cognitive mapping showed that the children who had a bird's-eye view on the small- and large-scale space tasks produced a number of "node," "path," and "landmark" and also could place the targets better than the children who did not have a bird's-eye view. It is discussed that there is relationship between a bird's-eye view and production of nodes, and that a bird's-eye view could affect children's cognitive mapping on the transition from route to configurational knowledge. 相似文献
32.
33.
Hiroshi Takahashi Nobuo Tsuda Shuichi Fujita Fumiaki Tezuka Haruo Okabe 《Pathology international》1990,40(9):655-664
Fifty-four adenoid cystic carcinomas (ACC) arising in major and minor salivary glands as well as in normal salivary glands were studied by immunohistochemistry for the presence of vimentin, neuron specific enolase (NSE), α1 -antichymotrypsin (α1 -ACT) and α1 -- antitrypsin (α1 -- AT). Five patterns of histological differentiation were found in ACC, and for the cellular components of each, it was possible to establish a special immunohistochemical profile. In ACC, vimentin-positive cells were observed in the outer tubular, cyst-lining and small angular cells. NSE was positive in the myoepithelial cells of normal salivary gland. Neoplastic cells of ACC showed NSE positivity mainly in the small angular cells and partly in the duct luminal cells. α1 -ACT was localized in the intercalated duct cells and serous acinar cells of normal salivary gland, and in the duct luminal cells of ACC. α1 -AT could not be detected in any of the epithelial cells of normal salivary gland. In ACC, eosinophilic hyaline material in the cribriform spaces was positive for α1 -AT, but no positivity was demonstrated in tumor cells. The present study showed that there are at least two populations of tumor cells in ACC: duct luminal cells that express α1 -ACT, thus indicating their ductal character, and small angular cells that express vimentin, characteristic of non-luminal cells. Moreover, our results indicate that α1 -AT is a useful marker of basement membrane-like material. 相似文献
34.
Kashimura T Kodama M Hotta Y Hosoya J Yoshida K Ozawa T Watanabe R Okura Y Kato K Hanawa H Kuwano R Aizawa Y 《Virchows Archiv : an international journal of pathology》2004,444(3):283-292
Coxsackievirus B is the most common cause of viral myocarditis and is particularly virulent in neonates and children. Adenovirus is also a leading cause of the disease. The determinant of tropism for both viruses is considered to be the expression of coxsackievirus and adenovirus receptor (CAR) in target organs. However, developmental change and physiological localization of CAR in the heart are unknown. We examined expression levels of CAR in rat hearts by quantitative real-time polymerase chain reaction and Western blot analysis and found that CAR decreased gradually during postnatal development, although CAR was detectable, even in adults. Immunohistochemistry revealed CAR on the whole surface of cardiomyocytes in immature rat hearts. In contrast, CAR was detected predominantly on intercalated disks in the adult heart and was accumulated especially at the contact point between the cultured cardiomyocytes, even though they were prepared from the neonatal rat heart. In conclusion, CAR was expressed abundantly on the whole surface of cardiomyocytes in immature rat hearts. Both the expression level and the localization of CAR are possible determinants of the susceptibility to viral myocarditis of neonates and children. 相似文献
35.
Effects of repeated subculturing and prolonged storage at room temperature of enterohemorrhagic Escherichia coli O157:H7 on pulsed-field gel electrophoresis profiles
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Iguchi A Osawa R Kawano J Shimizu A Terajima J Watanabe H 《Journal of clinical microbiology》2002,40(8):3079-3081
Three clinical strains of enterohemorrhagic Escherichia coli O157:H7 which were subcultured repeatedly or stored at room temperature over a 25-week period showed appreciable variations in their pulsed-field gel electrophoresis fragment patterns. The variations could be explained by a couple of spontaneous genetic events at most and thus did not invalidate the genetic lineage of the strains. 相似文献
36.
Amagai T Mouri T Kirii K Hori T Kaneko M Ohkawa H 《Clinical and experimental pharmacology & physiology. Supplement》2002,(29):S19-S22
1. Biliary atresia (BA), as a common disease in Japan, and cystic fibrosis (CF), as an extremely uncommon disease in Japan, were selected to assess the clinical significance of measurement of energy expenditure (EE). 2. Energy expenditure was significantly higher in children with BA than in normal children. 3. Measurement of EE in BA lead to clues to resolving its mechanism by novel assessment of interleukin-6 and leptin. 4. Energy expenditure in children with CF is also higher, but this has been addressed by nutritional intervention with additional calories. 5. Individualization of EE measurement is necessary in the analysis of pathological mechanisms and nutritional management of patients with both common and uncommon diseases. 相似文献
37.
We have addressed the question of whether antigen binding induces a conformational change in the heavy chain constant (C(H)) domain of antibodies using staphylococcal protein A or streptococcal protein G as probes, since these proteins are known to bind to IgG domains such as C(H)1 and C(H)2-C(H)3 domains. Biosensor assays on interactions between these proteins and mouse IgG specific to (4-hydroxy-3-nitrophenyl)acetyl (NP) or their enzymatic fragments conducted in the presence or absence of the hapten, NP-epsilon-aminocaproic acid (NP-Cap), showed that the binding of IgG to these proteins was inhibited by the binding of NP-Cap. The results of isothermal titration calorimetry also revealed that the association constant for the interaction of protein A with IgG2b decreased by the addition of NP-Cap. These results suggested that antigen binding induced conformational changes in binding sites for protein G or protein A located at C(H)1 and C(H)2-C(H)3 domains, respectively. 相似文献
38.
Ernesto Falcidia Agata Grillo Piero Pavone Nunzio Cutuli Haruo Takabayashi Rosario R. Trifiletti Conrad T. Gilliam 《American journal of medical genetics. Part A》2001,101(3):262-267
The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F‐positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell‐by‐cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21. © 2001 Wiley‐Liss, Inc. 相似文献
39.
During the immune response to T cell-dependent antigen, somatic hypermutation (SHM) is introduced into immunoglobulin (Ig) genes. The variable region is the target for SHM and it is here that DNA lesions are introduced and mutations are generated. It has been suggested that error-prone DNA polymerase(s) may play an important role in this mutagenesis phase. Recently, DNA polymerase kappa (Polkappa), which belongs to the Y-family of DNA polymerases, was identified. Since a hot spot of SHMs (RGYW motif) is also a hot spot of mutations by human Polkappa, this enzyme was suggested to be an SHM instigator. In order to address the question whether Polkappa is involved in SHM, we immunized Polkappa-deficient mice and analyzed the SHM of the Ig heavy chain gene. We found that the SHM frequency and spectrum were indistinguishable between the Polkappa knockout mice and control mice. These results suggested that Polkappa is not essential for this process. 相似文献
40.
Haruo Hagiwara Nobuo Ohwada Takeo Aoki Takeshi Suzuki Kuniaki Takata 《Medical molecular morphology》2008,41(4):221-226
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells
during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated
human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural
features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary
cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal
cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes
by bringing about contraction of the mucosal folds. 相似文献