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41.
Maeyama R Mizunoe Y Anderson JM Tanaka M Matsuda T 《Journal of biomedical materials research. Part A》2004,70(2):274-282
We developed a novel method of evaluating biofilm architecture on a synthetic material using green fluorescent protein-expressing Escherichia coli and red fluorescence staining of exopolysaccharides. Confocal laser scanning microscopy observation revealed the time course of the change in the in situ three-dimensional structural features of biofilm on a polyurethane film without structural destruction: initially adhered cells are grown to form cellular aggregates and secrete exopolysaccharides. These cells were spottily distributed on the surface at an early incubation time but fused to form a vertically grown biofilm with incubation time. Fluorescence intensity, which is a measure of the number of cells, determined using a fluorometer and biofilm thickness determined from confocal laser scanning microscopy vertical images were found to be effective for quantification of time-dependent growth of biofilms. The curli (surface-located fibers specifically binding to fibronectin and laminin)-producing Escherichia coli strain, YMel, significantly proliferated on fibronectin-coated polyurethane, whereas the curli-deficient isogenic mutant, YMel-1, did not. The understanding of biofilm architecture in molecular and morphological events and new fluorescence microscopic techniques may help in the logical surface design of biomaterials with a high antibacterial potential. 相似文献
42.
Duplication of part of 9q due to maternal 12;9 inverted insertion associated with pyloric stenosis 总被引:2,自引:0,他引:2
Y Yamamoto N Oguro T Nara H Horita N Niitsu S Imaizumi 《American journal of medical genetics》1988,31(2):379-384
We report on a 9-month-old boy who had duplication of the long arm of chromosome 9 [46,XY, -12, +der(12) inv ins (12;9)(p13;q32q13)mat.]. The clinical manifestations of the patient were different from those seen in distal 9q duplication. Pyloric stenosis appears to be common in cases with proximal 9q duplications. 相似文献
43.
The purpose of the present study was to investigate the interaction between the pre-landing activities and the stiffness
regulation of the knee joint musculoskeletal system and the takeoff speed during a drop jump (DJ). Nine healthy male subjects
performed a DJ test from the height of 50 cm. The surface electromyographic (EMG) activity of the vastus lateralis (VL) muscle
was recorded to evaluate both the pre-landing and post-landing muscle activation levels. Simultaneous recording of the jumping
motion and ground reaction force was performed by a high-speed video camera (100 frames·s–1), and a force platform was employed to allow joint moment analysis. Joint stiffness was calculated by a linear regression
of the knee joint moment/angle relationship. Elasticity of the knee extensor muscle during DJ was estimated by means of a
four-element muscle model consisting of a parallel elastic component, a series elastic component (SEC), a viscous damper,
and a contractile element. DJ performance correlated positively with the positive peak power of the knee joint (P<0.01) and with the moment of the knee joint at the end of stretch (P<0.01). However, there was no significant relationship between DJ performance and the positive peak power of the ankle joint.
The knee joint moment at the end of stretch correlated with the SEC stiffness during the transmission phase from the end of
the initial impact to the onset of the concentric action (P<0.01) and with the maximum rate of isometric force development of the knee extensors (P<0.01). Multiple regression analysis showed that the SEC stiffness during the transmission phase of the knee joint can be
explained by a combination of the pre-activity of the VL muscle and the knee joint angular velocity at touchdown (F=5.76, P<0.05). These results seem to emphasize the functional significance of the pre-programmed activity for controlling the subsequent
stiffness regulation and then contributing to the performance in DJ. Thus, it can be suggested that the centrally pre-programmed
activity and the associated elastic behavior of the SEC in the knee extensor muscle in conjunction with the muscle contractile
property play a major role in regulating the performance in DJ.
Electronic Publication 相似文献
44.
G Saigo R Ryo Y Nakaya N Yamaguchi R Ryo K Saigo K Ueda 《Rinsho byori. The Japanese journal of clinical pathology》1986,34(12):1417-1421
45.
Takaaki Ohmori Ryo Tabei Keiji Fukui Kazuhiko Sadamoto Saburo Sakaki 《Pathology international》1989,39(3):190-194
Two cases of meningioma revealing conspicuous plasmo lymphocytic tissue and hyalinized fibrous tissue components are reported. Histopathological examination of the plasmo lymphocytic infiltration was performed. Both lesions showed polyclonality of plasma cells as revealed by positive reactions for 1gG and paraimmunoglobulin χ- and λ light chains, and amyloid infiltration into the fibrous stroma and blood vessel walls. The histochemical and immunohistochemical characteristics of the lesion in relation to its etiology are briefly discussed. Acta Pathol. Jpn. 32: 190∼194, 1989. 相似文献
46.
47.
48.
Hepatocytes in vivo have a potential for liver regeneration, but it has been very difficult to reconstruct hepatic organoids in vitro. Recent studies have shown that small hepatocytes (SHs) can reconstruct hepatic organoids including functional bile canaliculi (BC). In the present study we analyzed the movement of BC formed in the hepatic organoids, focusing on the coordination of contraction and dilation among cells and the mechanism producing the coordination. Hepatic cells, including SHs, were isolated from an adult rat liver and cultured. Time-lapse images of BC movements were taken and analyzed in cells treated with or without cytochalasin B (CB). Time-lapse images revealed that all BC, regardless of region contracted in a coordinated manner. Actin filaments were observed along the BC even after the BC networks treated with CB dilated markedly. Microinjection of dye was also carried out to investigate the flow thorough BC. Secreted fluorescein from the injected cell flowed along BC, and gap junctional protein connexin 32 was expressed along BC networks, suggesting cell-to-cell communication. Thus, groups of hepatocytes in the hepatic organoids act in a coordinated manner through intercellular communication. 相似文献
49.
Saigo K Sugimoto T Narita H Ryo R Matsui T Yamamoto M Kumagai S 《Rinsho byori. The Japanese journal of clinical pathology》2000,48(1):49-53
Plasma macrophage colony-stimulating factor(M-CSF) levels were determined during peripheral blood stem cell harvest and autologous stem cell transplantation(PBSCT). Plasma of 10 patients were analyzed by using ELISA system. The average peak values during PBSCT were quite higher than those during harvest(20,092 vs 1,681 pg/ml). Peak values were observed mainly around leukocyte nadir(Phase II) during harvest. On the other hand, they were detected just after pretreatment(Phase I) during PBSCT courses. Moreover, samples showing extremely high M-CSF values(Phase I) were associated with increase in serum LDH levels. These data suggest that plasma M-CSF in Phase I are mainly derived from chemotherapy-induced cellular damage during PBSCT courses, and there might be different mechanisms to raise M-CSF around the nadir of leukocytes. It is necessary to elucidate the biological meanings of M-CSF. 相似文献
50.
I-J as an Inducible T Cell Receptor for Self 总被引:4,自引:0,他引:4
"Jedenfalls, wenn man davorsteht, dann sieht man sich selbstaber eben nicht wie in einem gewöhnlichen Spiegel, versteht sich. Man sieht nicht sein Äusseres, sondern man sieht sein wahres inneres Wesen. so wie es in Wirklichkeit beschaffen ist. Wer da durch will, der muß - um es mal so auszudrücken -in sich selbst hineingehen."
Die undendliche Geschichte, bei Michael Ende, K. Thiehemanns Verlag, Stuttgart, 1979. 相似文献
Die undendliche Geschichte, bei Michael Ende, K. Thiehemanns Verlag, Stuttgart, 1979. 相似文献