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181.
鳗鲡爱德华氏菌病的组织病理学研究 总被引:12,自引:2,他引:10
鳗鲡爱德华氏菌病病变性质为化脓性炎症。症理分型主要有两种:化脓性肝炎型、混合型。较早发生病变部位主要在肝脏,其化脓性病杜按病程分为初、中、晚期。肾脏、脾脏、胃粘膜、体表出现散在的脓肿、脓性溃疡、炎性血栓及血斑。此外,肝脏、肾脏实质细胞均出现变性和坏列、血管充血、出血等。本文详细报告了肝脏、脾脏、肾脏的超微结构变化并初步讨论了细胞、组织损伤的过程及细胞病理学、超微病理学意义。 相似文献
182.
人脑神经元特异性烯醇化酶的纯化方法 总被引:1,自引:0,他引:1
采用改良的Grace层析方法,经一次DEAE-Sephadex A50柱层析即从人脑中纯化了神经元特异性烯醇化酶,比活力为92.1U/mg,纯化倍数为59.4.该酶纯化后,经SDS-聚丙烯酰胺凝胶电泳鉴定为单一蛋白质谱带.此外,还测定了其部分理化性质,其亚单位分子量为45000,等电点pI为4.7,氨基酸组成分析表明其为一种酸性蛋白质;对2-磷酸甘油酸的Km值为5.6×10-4mol/L. 相似文献
183.
184.
肝细胞生长因子mRNA在成年小鼠和人胎儿不同器官中的表达 总被引:2,自引:0,他引:2
本实验从成年小鼠和胎龄4-5月的人胎儿不同器官中分离总RNA。经斑点印迹分析显示,肝细胞生长因子(HGF)mRNA在成年KM小鼠多种器官中表达,其表达水平由高到低依次为:肺、肝、肾、卵巢、睾丸、大脑和胃;在脾、心、骨髓、小肠和骨骼肌组织中以HGFmRNA。在胎龄4-5月的人胎儿中,HGFmRNA表达水平由高到低依次为:大脑、肝、腮腺、胃、小肠、肾、心和骨骼肌;肺和脾组织为阴性。由此可见,HGF在成 相似文献
185.
Synthesis of human insulin gene. VIII. Construction of expression vectors for fused proinsulin production in Escherichia coli 总被引:18,自引:0,他引:18
Analysis of Tn1725 insertions in the Pif+ plasmid pRS2496 showed the maximum limits of the F pif region to be between 43.7 and 47.15 on the 100-kb map of the F plasmid. The effect of these insertions on the expression of pif polypeptides indicated that two of the pif genes, pifA and pifC, lie within a polycistronic operon. 相似文献
186.
采用经典测量和染色体常规压片法,对龙牙百合(Lilium brownii var.viridulum Baker)3个地方品种的形态特征及核型进行研究。植株形态分析结果显示:‘江西’龙牙的株高、开花口径、种球重量和周长、中外层鳞片重量和长度以及鳞片扦插产生小鳞茎数等指标均显著大于‘大叶’龙牙和‘平头’龙牙;‘大叶’龙牙的叶片最长,均值为14.54 cm。花粉、叶表皮气孔及鳞片淀粉粒的微形态特征分析结果显示:‘江西’龙牙的花粉粒径最大,均值达111.76 μm;‘平头’龙牙的叶表皮气孔最长,气孔密度也最大(约47.6个/mm2);‘大叶’龙牙的淀粉粒径最大,均值为47.61 μm;‘江西’龙牙的淀粉粒大小分布更集中,差异性小。染色体核型分析结果显示:龙牙百合3个品种的染色体数目均为2n=2x=24,为二倍体,其中‘江西’龙牙核型公式为2n=2x=24=2m(2SAT)+6sm(2SAT)+12st(4SAT)+4t;‘平头’龙牙核型公式为2n=2x=24=4m+8sm+10st(4SAT)+2t;‘大叶’龙牙核型公式为2n=2x=24=2m(2SAT)+6sm+14st(4SAT)+2t,三者核型均为3B型。 相似文献
187.
水生植物叶片的功能性状特征与陆生植物有所不同,同时叶脉类型也显著影响叶片的功能性状。本研究选取9种具有不同叶脉类型的水生植物,通过对叶脉进行直接损伤,分析叶片性状(形态、色素含量和叶绿素荧光指标)在叶脉受损后的变化程度与叶脉类型的关系。结果显示:具有平行脉的3种水生植物对叶脉损伤具有较强的耐受性;具羽状脉的4种植物主脉受损后显著抑制叶片生长,而侧脉受损的影响在不同物种间有所不同,具有物种特异性。本研究可为大型湖泊水生植物修复的水生物种筛选提供参考。 相似文献
188.
本文研究结果表明低剂量的氦氖激光可以提高绵羊精清中GOT和LDH酶的活性,并对其机制作了初步的探讨。 相似文献
189.
Oscillations in free cytosolic calcium during IgE-mediated stimulation distinguish human basophils from human mast cells 总被引:1,自引:0,他引:1
Free cytosolic calcium ([Ca2+]i) levels increase after the stimulation of either human basophils or mast cells with anti-IgE antibody. Previous studies found that the mast cell [Ca2+]i response was graded in magnitude, according to stimulus strength, and that the activated level was free of oscillations. The current studies demonstrate several new features of the mast cell and basophil response. First, in mast cells, the transition to activated [Ca2+]i levels was abrupt (width = 6.5 +/- 2 s), after a period of quiescence whose duration (5 to 300 s) was a function of the strength of the stimulus. At optimal concentrations of anti-IgE, 97% of mast cells showed only abrupt transitions and oscillation-free activated calcium levels. In contrast, basophils showed marked oscillations whose magnitudes were partially dependent on the strength of stimulus. Like the mast cell, there was a quiescent period before the first transition and this period was also dependent on the strength of the stimulus. Oscillations were generally superimposed on an elevated [Ca2+]i level at a frequency of 0.5 to 3/min, had half-widths of 5 to 20 s, and were markedly chaotic in the frequency domain. In general, oscillations were more apparent at suboptimal concentrations of anti-IgE. Despite the apparent contrast in basophil and mast cell responses, oscillations (1 or 2 in a 10-min period) could be observed in a small percentage of mast cells and some basophils showed characteristics of mast cells. We tentatively conclude that mast cells and basophils utilize a similar mechanism of calcium mobilization but that the nonlinear characteristics of the calcium response may account for the mast cell/basophil differences. These studies indicated that the calcium kinetics, as measured by population averages, did not reflect the kinetics observed at the single cell level. Both mast cells and basophils had characteristics which could be described as graded and characteristics resembling all-or-nothing processes; the magnitude of a response was graded according the strength of stimulus while the kinetics profile appeared as an all-or-nothing event. 相似文献
190.
Endotoxin-induced cytokine gene expression in vivo. III. IL-6 mRNA and serum protein expression and the in vivo hematologic effects of IL-6 总被引:19,自引:0,他引:19
T R Ulich K Z Guo D Remick J del Castillo S M Yin 《Journal of immunology (Baltimore, Md. : 1950)》1991,146(7):2316-2323
Endotoxin (LPS) at sublethal doses injected i.v. into rats was found to induce IL-6 mRNA expression peaking at 1 to 2 h in whole organ RNA preparations of the spleen, liver, lung, bowel, and kidney. IL-6 serum protein levels also peaked at 2 h. TNF and IL-1, generally considered to be among the most rapidly released cytokines, also induced IL-6 expression. IL-6 in turn inhibited TNF and IL-1 expression, suggesting that IL-6 may be part of a negative feedback mechanism in the cytokine cascade. Dexamethasone down-regulated and Corynebacterium parvum up-regulated IL-6 expression, although the possibility cannot be excluded that these immunomodulating factors may in part have exerted their effects indirectly via the up- and down-regulation of TNF and IL-1. IL-6 injected i.v. at a pathophysiologically relevant dose caused a peripheral neutrophilia and mild myeloproliferative effect in the bone marrow. 相似文献