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41.
Expression of osteopontin (OPN) was investigated in the spinal cords of rats with clip compression injury. Western blot analysis demonstrated that OPN protein increased significantly in the spinal cord during the early stages after injury. The increased expression of OPN was partially paralleled by that of proliferating cell nuclear antigen (PCNA). Immunohistochemical staining showed that OPN was expressed in proliferating activated microglia/macrophages in core lesions and in some astrocytes at the periphery of lesions. These results indicate that expression of OPN protein increases mainly in activated microglia/macrophages after spinal cord injury, suggesting that OPN is related to cell proliferation during the early stages after injury, probably leading to tissue remodeling.  相似文献   
42.
The effect of the Maillard reaction on the allergenicity of squid tropomyosin (TM) was investigated. When TM was reacted with ribose (TM-ribose), its human-specific IgE-binding ability decreased markedly and alpha-chymotryptic digestibility of TM was also altered at the early stage of the Maillard reaction. On the other hand, the modification of the lysine residues in TM using 2,4,6-trinitrobenzenesulfonic acid had no effect on the allergenicity and alpha-chymotryptic digestibility of TM. Therefore, the structural change in TM induced by the Maillard reaction would cause the reduction of the allergenicity, rather than the block of lysine residues. Although peptic digestion diminished the specific IgE-binding ability of TM, the reduction of the allergenicity by the Maillard reaction remained after peptic digestion. These results suggest that hypersensitive reaction of TM-ribose in the human body might be lower than that of native TM.  相似文献   
43.
The expression of protein kinase C (PKC) was studied in the bovine retina by immunohistochemical analysis. Western blot analysis showed that PKC isoforms, including alpha, betaI, delta and theta, were detected in the bovine retina. By immunohistochemistry, both PKC alpha and betaI were expressed in all retinal layers, with an intense localization of both PKC alpha and betaI detected in bipolar cells in the inner nuclear cell layer and in some glial cells in ganglion cell layers. The immunoreactivity of both PKC delta and theta was quite weak in the retinal layers, compared with that of PKC alpha and betaI. These findings suggest that both conventional and novel PKCs are differentially expressed in the bovine retina.  相似文献   
44.
The expression pattern of CD44 was studied in the rat testis following ischemia/reperfusion (I/R) injury to elucidate the possible role of the CD44 adhesion molecule in acute experimental testicular torsion. Western blot analysis showed that CD44 expression began to increase significantly 24 hr after reperfusion, compared with the normal control; the increased expression persisted until 96 hr after I/R. Immunohistochemistry showed that, in the normal testis, CD44 was constitutively expressed mainly in ED2-positive resident macrophages in the interstitial space. After I/R, the majority of inflammatory cells in the interstitial space surrounding the damaged tubules were ED1-positive macrophages that were CD44-positive. These findings suggest that the significant increase in CD44 expression that occurs during the delayed phase after reperfusion originates from infiltrating macrophages possibly in anticipation of the migration and adhesion of additional macrophages into the affected testis.  相似文献   
45.
We developed a simple approach to combine broad classes of dissimilar materials into heterogeneously integrated electronic systems with two- or three-dimensional layouts. The process begins with the synthesis of different semiconductor nanomaterials, such as single-walled carbon nanotubes and single-crystal micro- and nanoscale wires and ribbons of gallium nitride, silicon, and gallium arsenide on separate substrates. Repeated application of an additive, transfer printing process that uses soft stamps with these substrates as donors, followed by device and interconnect formation, yields high-performance heterogeneously integrated electronics that incorporate any combination of semiconductor nanomaterials on rigid or flexible device substrates. This versatile methodology can produce a wide range of unusual electronic systems that would be impossible to achieve with other techniques.  相似文献   
46.
农业耕地土壤中114株农药降解菌的分离与筛选   总被引:3,自引:0,他引:3  
根据农田使用农药史选择灭蝇胺、氯氰菊酯、异丙威进行农药富集培养和平板划线分离,在28种长期受农药污染的不同作物耕地土壤中分离到114株农药降解菌,并用高效液相色谱法测试对吡虫啉(100μg/ml)的降解率,72 h后进行检测。结果 114株降解菌中用吡虫啉筛选到10株降解率达到25%以上的细菌,降解率为10%~25%之间的细菌为78株,降解率小于10%的细菌为26株。对农药降解效果较好的降解菌主要分布在长期大量使用农药的蔬菜作物(大姜、大葱、芦笋等)耕地土壤,而施药相对较少的果园和棉花田中降解菌的数目和降解能力偏低。  相似文献   
47.
This study quantifies the effects of marked weight gain on glucose and insulin metabolism in 16 cats which increased their weight by an average of 44.2% over 10 months. Significantly, the development of feline obesity was accompanied by a 52% decrease in tissue sensitivity to insulin and diminished glucose effectiveness. In addition, glucose intolerance and abnormal insulin response occurred in some cats. An important finding was that normal weight cats with low insulin sensitivity and glucose effectiveness were at increased risk of developing impaired glucose tolerance with obesity. High basal insulin concentrations or low acute insulin response to glucose also independently increased the risk for developing impaired glucose tolerance. Male cats gained more weight relative to females and this, combined with their tendency to lower insulin sensitivity and higher insulin concentrations, may explain why male cats are at greater risk for diabetes. Results suggest an underlying predisposition for glucose intolerance in some cats, which is exacerbated by obesity. These cats may be more at risk of progressing to overt type 2 diabetes mellitus.  相似文献   
48.
49.
This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.  相似文献   
50.
Induced pluripotent stem cells (iPSCs) are thought to be highly beneficial in the field of regenerative medicine and are believed to overcome immunogenic barriers to cell transplantation. However, issues remain regarding their safety and efficiency for medical use. Furthermore, some recent reports have suggested that iPSCs could be targeted by the autologous immune system. To promote practical applications of iPSCs, in depth research using appropriate animal models is needed and porcine species appear to provide an ideal model. Recent studies have focused on the generation of porcine iPSC cells, but no investigations of their immunological properties have been conducted to date. In the present study, we generated putative iPSCs from porcine somatic cells and measured major histocompatibility complex (MHC) expression on the iPSCs and their derivatives. Compact colonies that expressed pluripotent markers appeared 11 days after viral infection. Embryonic bodies (EB) were produced and differentiated into three germ layers in vitro. Karyotyping and swine leukocyte antigen (SLA) typing showed that the iPSCs were identical to parental somatic cells. Porcine iPSCs expressed only low levels of MHC class I and moderately increased levels on their differentiated derivatives, whereas MHC class II was rarely expressed. In the presence of interferon-gamma (IFN-γ), the expression of MHC class I was elevated on differentiated iPSCs, and gradually decreased after withdrawal of the cytokine. Our data suggest that porcine iPSCs could be useful for preclinical studies of the efficiency and viability of iPSCs, and for devising strategies to rescue transplanted cells from the autologous immune system.  相似文献   
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