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121.
观察妥布霉素伤用凝胶的体外抗菌活性 ,为临床应用提供试验依据。采用平皿二倍稀释法测定了妥布霉素伤用凝胶对临床分离的 12 0株临床常见的革兰氏阳性及革兰氏阴性菌的体外抗菌作用。以对青霉素敏感的金葡菌、表葡菌、对庆大霉素敏感的大肠杆菌、敏感绿脓杆菌的作用为最强 ,MIC50 均为 0 2 5mg/L。妥布霉素伤用凝胶抗菌谱较广 ,对试验中的革兰氏阳性及革兰氏阴性菌均具有较强的杀灭或抑制作用 ,显示出较好的抗菌活性。 相似文献
122.
以甲基丙烯酸羟乙酯为原料,过硫酸铵/偏重亚硫酸钠为引发体系,二甲基丙烯酸三乙二醇酯为交联剂,采用溶液聚合法制备了聚甲基丙烯酸羟乙酯水凝胶(PHEMA)人工晶状体材料。系统考察了聚合反应时间、温度及引发剂和交联剂的用量等对该水凝胶材料机械强度、平衡水含量(EWC)的影响,并对PHEMA水凝胶的结构和光学性能进行了表征。实验结果表明,PHEMA水凝胶的最佳合成条件为:引发剂0.5wt%,交联剂1.0wt%,反应温度40℃,反应时间36h。在此条件下制备的PHEMA水凝胶的拉伸强度达到0.57MPa,邵氏A硬度为23.0,平衡含水量超过40%,透光率≥97%。 相似文献
123.
γδ T cells represent one unique recognition pattern, the limited recognition, which distinguishes from the specific recognition for αβ T cells and pattern recognition for macrophages. Vδ1 γδT cell is the major subset of human γδT cells, which predominates in mucosal tissue including the intestinal epithelia. Presently, a few antigens that human Vδ1TCR can recognize have been identified. Among them, MHC class I chain-related molecules A (MICA) have been studied most intensively. Besides Vδ1TCR, MICA is also the ligand of NKG2D, a C-type lectin-like activating immunoreceptor. In human, only Vδ1 cells can simultaneously express both types of receptors of MICA while NK cells, αβ T cells and other subsets of γδT cells likewise express NKG2D. Although the precise mechanisms are still enigmatic, this distinct pattern of Vδ1 cells recognizing MICA predicts unique biological significance of Vδ1 cells in immune defense. Recent years, some progresses have been made in this issue. In this review we summarize the related reports and put forward some novel views based on our group's studies. 相似文献
124.
Immunoprophylaxis of Chlamydia trachomatis lymphogranuloma venereum pneumonitis in mice by oral immunization. 下载免费PDF全文
Groups of BALB/c mice were orally immunized with chlamydiae and challenged intranasally to determine whether oral immunization offers protection against pulmonary disease and to characterize the nature and kinetics of the chlamydial antibody response in the lung and other mucosal sites. Protection by oral immunization from chlamydial lung disease was demonstrated by lack of replication of the organism and the lack of chlamydial antigen in lung tissue. The chlamydial immunoglobulin A (IgA) antibody response was present at all body sites, reaching peak levels in the lung as well as in the serum. Classical IgA booster effect kinetics was observed after intranasal challenge, especially in the lung. Specific IgG antibody was detected at all body sites but at lower levels. Furthermore, animals immunized orally had no pneumonic process, as determined by histopathology. These studies also suggest that passively acquired specific serum IgG antibody may not significantly influence the course of mucosal replication of the organism. These observations indicate that oral immunization activating the gut-associated lymphoid tissue system gave total protection against chlamydial lung disease, suggesting migration of immunologically competent cells from the intestine to the lung. 相似文献
125.
Cortical spreading depression (SD) is characterized by propagation of neuronal/glial membrane depolarization throughout the unilateral cerebral cortex and has been linked to several neurological disorders, including migraine aura and epilepsy. SD induction resulted in a dramatic increase in BrdU-incorporated cells in the ipsilateral cortical hemisphere that was dependent on the number of elicited SD. Immunohistochemical studies revealed that 53% of the BrdU-labeled cells in the SD-generated cortex were NG2 immunopositive and 25% were OX-42 immunopositive. The remaining 22% of BrdU-incorporated cells showed no immunoreactivity to GST-rr, GFAP, NeuN, NG2 or OX-42.These data indicate that functional excitation of the cerebral cortex induces proliferative response in cortical cells, which may subsequently differentiate into glial progenitor or microglia within 3 days after stimulation. 相似文献
126.
S. Sharmin M. Shiota E. Murata P. Cui H. Kitamura M. Yano H. Kido 《Inflammation research》2002,51(4):195-200
OBJECTIVE AND DESIGN: Investigation of the role of a novel inflammatory mediator 31-amino acid endothelin-1 [ET-1 (1-31)], a major ET derivative in granulocytes, in eosinophil recruitment after its subcutaneous administration to mice. METHODS: Various ET-1 derivatives (100 pmol), with or without ET receptor antagonists (200 pmol), were administered subcutaneously to mice, and then the eosinophil migration into and chemokine levels in the injected loci were analyzed. RESULTS: ET-1 (1-31) and a 21-amino acid endothelin-1 (ET-1), but not big ET-1, induced eosinophil migration into the injected loci with a peak after administration for 12 h, and increased the levels of eotaxin and interleukin-5 with peaks at 6 and 24 h, respectively. These effects of ET-1(1-31) and ET-1 were significantly inhibited by an ETA receptor antagonist, BQ-123, but not by an ETB receptor antagonist, BQ-788. CONCLUSION: Novel bioactive ET-1 (1-31) induces local eosinophil migration, and increases in eotaxin and interleukin-5 through an ETA or ETA-like receptor. 相似文献
127.
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129.
实验用foS蛋白免疫组织化学方法,研究了中枢神经系统兴奋性介质N-氨基-D-门冬氨酸诱导大鼠下丘脑内c-fos的表达.N-氨基-D-门冬氨酸注射大鼠皮下后,观察了fos阳性细胞在下丘脑内开始出现与消失的时程相关以及在下丘脑内的分布.结果表明:给N-氨基-D-门冬氨酸后30分开始出现fos阳性细胞,1~2小时达高峰,4~8小时消失.fos阳性细胞主要分布于视上核、室旁核和弓状核,视上核和室旁核中fos阳性细胞分别占细胞总数的57.8%和63.6%,在弓状核中占细胞总数的60.6%. 相似文献
130.
Human granulocyte-macrophage colony-stimulating factor (hGM-CSF): identification of a binding site for a neutralizing antibody. 总被引:2,自引:0,他引:2
E Nice P Dempsey J Layton G Morstyn D F Cui R Simpson L Fabri A Burgess 《Growth factors (Chur, Switzerland)》1990,3(2):159-169
One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition. 相似文献