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排序方式: 共有4265条查询结果,搜索用时 31 毫秒
1.
Ong Jia Sin Taylor Todd D. Yong Cheng Chung Khoo Boon Yin Sasidharan Sreenivasan Choi Sy Bing Ohno Hiroshi Liong Min Tze 《Probiotics and antimicrobial proteins》2020,12(1):125-137
Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed... 相似文献
2.
Y. Norimatsu H. Kouda T. K. Kobayashi K. Shimizu K. Yanoh C. Tsukayama Y. Miyake E. Ohno 《Cytopathology》2009,20(6):395-402
Objective: The purpose of this study was to examine the utility of SurePath‐liquid‐based cytology (LBC) compared to conventional cytological preparations (CCP) in the identification of endometrial carcinoma. Methods: During a 13‐month period, direct endometrial samples were collected from 120 patients using the Uterobrush. The material comprised 30 cases each of endometrial carcinoma, proliferative endometrium, secretory endometrium and atrophic endometrium. The following points were investigated:(i) the frequency of cell clumps in endometrial carcinoma; (ii) the area of cell nuclei; (iii) overlapping nuclei. Results: (i) Comparison of the frequency of cell clumps with irregular protrusion pattern and papillo‐tubular pattern showed no statistically significant difference in either type of cell clump between CCP and LBC. (ii) Comparison of the nuclear area of cells showed a sequential decrease from endometrial carcinoma to secretory endometrium, to proliferative endometrium and to atrophic endometrium, which was significant in CCP and LBC. (iii) Nuclear area was significantly lower with LBC compared with CCP in endometrial carcinoma, secretory endometrium and proliferative endometrium but not atrophic endometrium. (iv) Comparison of the degree of overlapping nuclei showed a sequential decrease from endometrial carcinoma to proliferative endometrium, to secretory endometrium and to atrophic endometrium, which was significant in both CCP and LBC. (v) Comparison of the degree of overlapping nuclei between CCP and LBC showed no significant difference for normal types of endometrium, but LBC had significantly higher values (P < 0.0001) in endometrial carcinoma than in CCP. Conclusions: The results of this study revealed that applying diagnostic criteria used in CCP to LBC was easy to achieve, because LBC had excellent cytoarchitectural preservation and cells were well presented. Although we have not examined all cytological features of malignancy and have not considered atypical hyperplasia, we believe that this method may be a useful tool in the diagnosis of endometrial cytology. 相似文献
3.
Michinari Hamaguchi Koichiro Maeno Yoshiyuki Nagai Masao Iinuma Tetsuya Yoshida Toshisada Matsumoto 《Microbiology and immunology》1980,24(1):51-63
When p-fluorophenylalanine (FPA) was added to influenza virus RI/5+-infected cells 4 hr after infection, virus-specific proteins were synthesized but infectious progeny virus was not produced. In these cells, synthesis of viral RNA was strongly inhibited and nucleoprotein (NP) antigen was found predominantly in the nucleus in contrast to untreated cells in which NP antigen was distributed throughout the whole cell. The intracellular location and migration of NP were examined by isotope labeling followed by fractionation of infected cells. In untreated cells, a large portion of the NP was present in the cytoplasm and most of it was detected in the form of ribonucleoprotein (RNP). In contrast, in FPA-treated cells little viral RNP was detectable and NP was present predominantly in the nucleus in a nonassembled, soluble form. When FPA was removed from the culture, synthesis of viral RNA was soon restored and a large amount of viral RNP appeared in the cytoplasm; this was followed by the production of infectious virus. The results of the experiments suggest that the NP synthesized in the presence of FPA is not assembled into viral RNP because of the lack of available RNA, and such NP migrates readily into the nucleus and accumulates there. 相似文献
4.
Lin Cui Kenoki Ohuchida Kazuhiro Mizumoto Taiki Moriyama Manabu Onimaru Kohei Nakata Toshinaga Nabae Takashi Ueki Norihiro Sato Yohei Tominaga Masao Tanaka 《PloS one》2010,5(8)
Although CD133 has been reported to be a promising colon cancer stem cell marker, the biological functions of CD133+ colon cancer cells remain controversial. In the present study, we investigated the biological differences between CD133+ and CD133− colon cancer cells, with a particular focus on their interactions with cancer-associated fibroblasts, especially CD10+ fibroblasts. We used 19 primary colon cancer tissues, 30 primary cultures of fibroblasts derived from colon cancer tissues and 6 colon cancer cell lines. We isolated CD133+ and CD133− subpopulations from the colon cancer tissues and cultured cells. In vitro analyses revealed that the two populations showed similar biological behaviors in their proliferation and chemosensitivity. In vivo analyses revealed that CD133+ cells showed significantly greater tumor growth than CD133− cells (P = 0.007). Moreover, in cocultures with primary fibroblasts derived from colon cancer tissues, CD133+ cells exhibited significantly more invasive behaviors than CD133− cells (P<0.001), especially in cocultures with CD10+ fibroblasts (P<0.0001). Further in vivo analyses revealed that CD10+ fibroblasts enhanced the tumor growth of CD133+ cells significantly more than CD10− fibroblasts (P<0.05). These data demonstrate that the in vitro invasive properties and in vivo tumor growth of CD133+ colon cancer cells are enhanced in the presence of specific cancer-associated fibroblasts, CD10+ fibroblasts, suggesting that the interactions between these specific cell populations have important roles in cancer progression. Therefore, these specific interactions may be promising targets for new colon cancer therapies. 相似文献
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Cell hybridization of phytohemagglutinin (PHA)-stimulated human peripheral blood lymphocytes (PBL) with murine lymphoma (EL-4) provided three hybridomas (MHH-16, MHH-20, and MHH-22) which spontaneously produced human mitogenic factor (MF). MHH-16 was serially subcloned by limiting dilution procedures, which resulted in maintaining two subclones producing human MF spontaneously for more than one year (PQL-3 and PQL-5 subcloned lines). Human MF (MHH-MF) derived from supernatants of PQL-5 line cultures had a molecular weight (m.w.) of about 26,000–30,000 daltons (the major peak) with a minor peak with an m.w. of 15,000 daltons on Sephadex G-100 chromatography, and at a high concentration of NaCl (1 m), the activity of the 26,000–30,000-m.w. fraction became weak and that of the 15,000-m.w. fraction became predominant. MHH-MF had an isoelectric point of pH 5.0–6.5. On DEAE-cellulose chromatography, MHH-MF was eluted at a fairly low salt concentration (sodium phosphate buffer 0.02 M, pH 8.0, NaCl 10 mm). After periodate treatment of this MHH-MF, the mitogenic activity almost disappeared. MHH-MF was relatively unstable to heating at 56 C for 20 min. In the presence of tunicamycin (0.3μg/ml), an inhibitor of N-linked glycosylation, the synthesized MHH-MF showed a decrease in m.w. as follows: the major peak shifted from 26,000–30,000 to 23,000 daltons and the minor peak from 15,000 to 10,000 daltons on Sephadex G-100 chromatography. In internal labeling experiments with [3H]leucine, the 3H-labeled MF was partially purified, with mitogenic activity as a guide. This 3H-labeled MHH-MF fraction could be absorbed by PHA blasts but not by normal PBL. On SDS-PAGE under reducing conditions, only the radioactive peak of the 15,000-dalton fraction was recovered. MHH-MF obtained from the hybridoma culture supernatants may be a dimer of the 15,000-dalton fraction and a glycoprotein. 相似文献
7.
Visual afferents to the cat fastigial nucleus (FN) have been studied with single unit recordings and horseradish peroxidase techniques. A total of 158 cells responding to electrical stimulation of the optic chiasm (OCh) were extracellularly recorded from the dorsocaudal part of the FN. They were classified into three groups: type-1 cells (48%) which showed early suppression and late facilitation; type-2 cells (38%) which showed early facilitation and late suppression; type-3 cells (14%) which exhibited long lasting suppression with no signs of facilitation. Eight of 32 cells tested showed the same response patterns to photic stimulation as to electrical stimulation of the OCh. None of the cells responding to electrical and photic stimulation, however, were found in the rostral and ventral parts of the FN. Furthermore, 29 cells which responded to electrical stimulation of the OCh were tested for responses to moving pattern stimulation. Seven (4 type-2 cells and 3 type-3 cells) of the 29 cells showed clear modulation, reflecting the velocity component of a horizontally moving pattern. However, none of 13 type-1 cells tested exhibited apparent modulation in relation to movement of the pattern. In order to trace the possible pathways mediating visual signals to this part of the FN, the horseradish peroxidase (HRP) method was used. Injection of HRP into the caudal FN resulted in the labelling of many cells, predominantly in the medial (M) and the descending (D) vestibular nuclei and in lobules VI and VII of the cerebellar vermis. A series of experiments further indicated the presence of possible pathways propagating visual signals to the caudal FN. The main routes are: 1) via the nucleus of the optic tract (NOT)--the dorsal part of the medullary reticular formation--the M and the D vestibular nuclei--to the FN, and 2) via the superior colliculus--the pontine nuclei--vermal lobules VI and VII--to the FN. The different physiological response patterns of FN cells may indicate that several types of visual signals involved with visually guided movements impinge upon the dorsocaudal FN. 相似文献
8.
The AtXTH28 Gene, a Xyloglucan Endotransglucosylase/Hydrolase, is Involved in Automatic Self-Pollination in Arabidopsis thaliana 总被引:1,自引:0,他引:1
Kurasawa Kasumi; Matsui Akihiro; Yokoyama Ryusuke; Kuriyama Tomoko; Yoshizumi Takeshi; Matsui Minami; Suwabe Keita; Watanabe Masao; Nishitani Kazuhiko 《Plant & cell physiology》2009,50(2):413-422
Successful automatic self-pollination in flowering plants isdependent on the correct development of reproductive organs.In the stamen, the appropriate growth of the filament, whichlargely depends on the mechanical properties of the cell wall,is required to position the anther correctly close to the stigmaat the pollination stage. Xyloglucan endotransglucosylase/hydrolases(XTHs) are a family of enzymes that mediate the constructionand restructuring of xyloglucan cross-links, thereby controllingthe extensibility or mechanical properties of the cell wallin a wide variety of plant tissues. Our reverse genetic analysishas revealed that a loss-of-function mutation of an ArabidopsisXTH family gene, AtXTH28, led to a decrease in capability forself-pollination, probably due to inhibition of stamen filamentgrowth. Our results also suggest that the role of AtXTH28 inthe development of the stamen is not functionally redundantwith its closest paralog, AtXTH27. Thus, our finding indicatesthat AtXTH28 is specifically involved in the growth of stamenfilaments, and is required for successful automatic self-pollinationin certain flowers in Arabidopsis thaliana. 相似文献
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10.
Summary An unusually long Y chromosome was described in the phenotypically normal father and paternal grandfather of a girl with Down's syndrome, and likewise in a male infant with multiple malformations and his father, normal in phenotype. Measurements revealed that the long Y chromosome corresponded in length to autosomes of group 16–18.Information was obtained to show that the increased length of the Y chromosome was an inheritable character, and that a long Y chromosome was not always associated with an abnormal phenotype (or phenotypes).Contribution No. 585 from the Zoological Institute, Hokkaido University. 相似文献