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51.
钙调素对微管组装的调节作用 总被引:1,自引:1,他引:1
利用我们建成的钙调素表达可调细胞模型-RC3细胞,对CaM高表达时微管组装行为进行了研究,当用生理剂量的地塞米松处理RC3细胞,细胞内CaM水平提高,而管蛋白浓度没有变化,造成钙调素/管蛋白比值上升,MT解聚,但同时加入CaM拮抗剂三氟拉嗪处理时,则可抑制MT的解聚,C3H10T1/2转化细胞CaM含量的增加是引起MT解聚的主要因素,TFP处理可恢复MT组装。RC3细胞CaM高表达导致MT解聚的实 相似文献
52.
Refractoriness to Gal N toxicity occurs especially in fetal rats, newborn rats, and in rats after partial hepatectomy. An injury however (laparotomy, incision on the back or ip BaSO4 suspension), prior to Gal N administration, also inhibits Gal N toxicity. In all these circumstances high levels of rat α2-macrofetoprotein (αMFP) occur. This protein is an acute phase reactant and is identical to rat α2-macroglobulin. αMFP isolated from the serum of injured rats and then administered to normal rats strongly inhibits Gal N toxicity. When time interval between the preceding injury, provoking αMFP production and Gal N administration shortens, the inhibiting effects are less and αMFP production remains low.During resistance to Gal N, the primary and secondary biochemical lesions of Gal N persist and the protecting effect of αMFP must be due to another mechanism, operating in later phases of cell injury. Very probably this is attributable to the stabilizing effect on membranes of hepatocytic organelles and the plasma membranes. As αMFP is an acute phase reactant the importance of these proteins to the course of hepatitis must be considered. 相似文献
53.
A low molecular weight (LMW) antigen of Eimeria tenella, initially identified using a murine monoclonal antibody (mAb C34F1) raised against E. tenella sporozoites, was partially characterized using enzymatic degradation, solvent extraction, and immunization into various inbred
lines of mice. The LMW antigen could be isolated using Folch extraction (methanol/chloroform/water) and the epitope recognized
by mAb C34F1 was resistant to degradation by α-amylase, pronase, and proteinase K, but was sensitive to sodium m-periodate treatment or digestion using mixed glycosidases (from Turbo cornutus). These observations suggest that the antigenic epitope recognized by mAb C34F1 is carbohydrate-dependent and, based on our ability to isolate the LMW antigen by Folch extraction, the epitope probably
resides on a polar glycolipid. The inability of sporozoite-immunized nude mice to elicit a serum antibody response to this
molecule indicates that it acts as a T-dependent antigen. Furthermore, sporozoite-immunized male CBA/N mice (with an X-linked
immunodeficiency) also failed to elicit a serum antibody response to this molecule, which is consistent with a carbohydrate
antigenic epitope. We propose that this antigenic molecule be designated ET-GL1 to reflect its origin and probable structure
(E. tenella glycolipid 1).
Received: 30 June 1999 / Accepted: 2 December 1999 相似文献
54.
甲襞、球结膜微循环的应急观测方法是在甲襞、球结膜微循环加权积分综合定量评价方法的基础上,保留权值为4、3的指标,同时观察血管清晰度和红细胞聚集二项指标而形成。同时提供其应急观测积分表、异常分度积分值、诊断标准,并与常规方法进行比较,证明其可以反映绝大部分流态类指标和大部分形态类指标及重要的袢周改变,没有丢失微循环重度异常的信息,保证了重度异常诊断的正确。但在大致正常、轻度异常和中度异常的诊断中应急方法部有判重的倾向,说明应急方法漏掉了一些信息,不能全面地了解微循环的改变,造成了判重的倾向。因此应急方法不能代替常规方法,只能在特定条件下应用。 相似文献
55.
c AMP反应成分结合蛋白 (c AMP response elem ent-binding protein,CREB)是一种转录因子 ,它在磷酸化之后可调节靶基因的转录。 CREB在 13 3位置的丝氨酸的磷酸化 ,与脊髓中伤害性传入的处理有关 ,本文作者等用特殊抗体对此进行了免疫细胞化学研究。在正常大鼠 ,虽然几乎所有脊髓神经元的核中都可见 CREB的轻度着色 ,但磷酸化的 CREB仅见于双侧腰段脊髓的 ~ 层 (75± 15 vs60± 18)和 层 (9± 3 )。用福尔马林注射引起一侧后脚掌出现炎症时 ,可在双侧腰段脊髓看到磷酸化CREB细胞核的快速 (小于 5 min)和节段性的显著增多 ;它们主要分布在双侧背角表层 ~ 层 (2 5 4± 2 0 vs 2 62± 2 3 )、 层(115± 13 )和双侧 ~ 层 (3 46± 2 0 vs3 2 8± 2 6) ;而在对照和炎症组大鼠的胸段脊髓中均未见磷酸化 CREB的增加。在注射CFA诱发一侧炎症或切断一侧坐骨神经的实验组大鼠 ,也可看到至少延续到第三天的强而双侧性的 CREB的磷酸化。这种由一侧后肢伤害性传入引致腰段脊髓中镜像式双侧 CREB磷酸化的出现 ,与一般看到的损伤传入只在同侧脊髓背角引起某些神经化学改变的结果不同 ,可能是人神经损伤后或在实验动物中出现对侧镜像式疼痛过敏现象的基础 相似文献
56.
The open reading frame 3 (ORF3) of the severe acute respiratory syndrome coronavirus (SARS-CoV) genome encodes a predicted 154-amino acid protein, which lacks similarities to any known protein, and is named 3b. In this study, it was shown that 3b protein was predominately localized to nucleus with EGFP tag at its N- or C-terminus. The localization patterns were similar in different transfected cells. Immuno-fluorescence assay revealed that 3b protein was co-localized well with C23 in nucleolus. C23, B23 and fibrillarin all are important nucleolar proteins, which localize in the region of the nucleolus. Co-transfection of p3b-EGFP with pC23-DsRed, pB23-DsRed and pfibrillarin-DsRed further confirmed 3b's nucleolus localization. With construction of serial truncated mutants of 3b, a region (residues 134-154 aa) responsible for nucleolar localization was determinated in 3b protein. These results provide a new insight for further functional studies of SARS-CoV 3b protein. 相似文献
57.
Using a subtractlve strategy, we have cloned an activation-relatedgene from a human B cell cDNA library. Sequence analysis revealedthat this gene was identical to H12.3, a gene belonging to anexpanding family of guanlne nucleotlde-blndlng protein ßsubunlts. The expression of H12.3 was induclble in the latephase of mltogen-stlmulated T and B cells. In T cells, IL-2and IL-4 by themselves had no direct effect on the expressionof H12.3, but they could augment the level of steady-state H12.3mRNA stimulated by phytohemagglutlnln. On the other hand, IFN-and IL-6 had no obvious effect on the expression in B cellswith or without Staphytococcus aureus Cowan l-stlmulatlon. CyclosporinA, a strong immunosuppressant, Inhibited the mltogen-stlmulatedexpression of H12.3, but rapamycin, another such agent, didnot. In synchronized Jurkat cells, the expression of H12.3 hadno cell cycle-dependent decrease in S and G2/M phase, whilecyclin E, which controls the progression of the cell cycle unlate G1 phase, did show a periodic expression pattern. The resultssuggest that H12.3 might be involved in regulation of lymphocyteactivation. 相似文献
58.
Liang Shan Yasushi Nakamura Misa Nakamura Toyoharu Yokoi Kennichi Kakudo 《Pathology international》1998,48(8):569-574
Hyperparathyroidism refers to a term representing a wide spectrum of parathyroid disorders that are characterized by the increased production of parathyroid hormone. Hyperparathyroidism was once thought to be tare but is now more commonly recognized, aifecting 1 in 500 women over 40 years of age. Yet the interpretation of parathyroid pathology is still controversial and confusing. Over the past 10 years, genetic changes ( ret and menin genes) involved in the pathogenesis of MEN 2 and MEN 1 have been discovered in succession. Different mutations of the calcium-sensing receptor gene have been identified in neonatal severe hyperparathyroidism and familial hypocalciuric hypercal-cemia, respectively. The HRPT 2 gene responsible for the development of heredltaty hyperparathyroidism and jaw tumors has been localized on the 1q21–31 locus. Several genetic alterations have also been characterized in primary and secondary hyperparathyroidism. Different genetic alterations appear to involve the development of different types of hyperparathyroidism. These novel advances give us new insights into the pathogenesis of hyperparathyroidism and allow better differentiation between the different types of parathyroid disorders. 相似文献
59.
给SD大鼠皮下埋植内含17β-雌二醇硅橡胶管30、60、120天后,发现大鼠垂体重量随给药时间延长呈持续性增加;用放射免疫法测定血浆催乳素含量,亦依次明显升高;用Northern印迹杂交方法检测垂体细胞中PRL基因,发现PRL mRNA含量也依次显著增加,但其增加却远低于血浆PRL含量的增加,提示β-雌二醇除了促进PRL基因的转录外,还可能增加PRL mRNA的翻译效率。 相似文献
60.
目的:探讨黄芪-当归药对(3∶1)对气虚血瘀模型大鼠的益气活血作用,从特征图谱、药效物质辨识、入血成分对比三方面入手,为临床合理用药及复方药效物质辨识与质量控制提供理论依据。方法:使用高效液相色谱法(HPLC)建立黄芪-当归(3∶1)指纹图谱,采用超高效液相色谱-四级杆-静电场轨道阱联用技术(UPLC-Q-Exactive Orbitrap-MS)分析水煎液成分;选用SPF级成年雄性Wistar大鼠,随机分为空白组、模型组、黄芪-当归3∶1组及黄芪-当归5∶1组,每日通过控制食量及凉水游泳制备气虚血瘀模型,同时各组每天给药(水)1次,给药组剂量10.2 g·kg-1,模型组和空白组给予等量的蒸馏水,连续15 d。观察大鼠一般状况;记录各组大鼠体质量,全血及血浆黏度,胸腺指数和脾脏指数,血清中三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、大鼠血管性血友病因子(vWF)水平及ATP/ADP值;苏木素-伊红(HE)及扫描电镜观察血管内皮形态;UPLC-QExactive Orbitrap-MS分析血清中的原型及代谢成分。结果:建立了黄芪-当归(3∶1)指纹图谱;UPLC-Q-Exactive ... 相似文献