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991.
992.
LIU Zhi-qin JIANG Yu-feng YUE Xiao-li FAN Yong-ping WANG Xi-mei HUANG Qi-fu 《园艺学报》2006,22(9):1816-1819
AIM:To observe the antipyretic effect of Naoreqing (NRQ) oral solution in rabbits with endotoxin-induced fever.METHODS:The ET-induced fever model was established in rabbits.The digital thermometer was used to register rectal temperature.The endothelin content in blood plasma,and tumor necrosis factor-α (TNFα) in blood serum were determined by radioimmunoassay.The activities of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) in plasma were measured by the assay of chromogenic substrate.At the same time,the pathology of lung,kidney and liver were observed.RESULTS:① NRQ showed obvious antipyretic effect in the rabbits with endotoxin-induced fever (P<0.01).② NRQ inhibited the endothelin content in plasma and TNFα content in serum,and at the same time reduced activity of PAI (P<0.01) and improved activity of t-PA in plasma (P<0.01).③ NRQ reduced the pathology of congestion of lungs,liver and renal in febrile rabbits.CONCLUSION:NRQ has an antipyretic effect .The mechanism is maybe related to its adjusting the balance of coagulant substance and anticoagulant substance,and at the same time inhibiting the secretion of TNFα in febrilic rabbits. 相似文献
993.
SUN Xiao-cai LI Wen-bin△ LI Qing-jun LI Shu-qin ZHANG Min XIAN Xiao-hui QI Jie CHEN Wei-na LIU Miao 《园艺学报》2005,21(12):2422-2426
AIM: The present study was designed to observe the effect of [D-Arg1, D-Trp7,9, Leu11]-substance P (spantide), a non-selective antagonist of NK receptors, on the up-regulation of nitric oxide synthase (NOS) induced by formalin test. METHODS: Formalin (5%, 0.2 mL) was subcutaneously injected into the plantar side of the right hind paw to produce persistent pain and hyperalgesia. The pain response was determined by spontaneous flinch reflex test. NOS expression was examined using NADPH-d histochemical staining. Spantide was intrathecally injected via L5-L6 intervertebral space 5 min prior to the formalin injection. RESULTS: Injection of formalin resulted in a characteristic behavioral response consisting of vigorous scratching, biting, licking and lifting of the injected hind paw from the box's bottom. Following these behavioral responses, the NOS expression was up-regulated in the pericentral canal region of the L5 segment of the spinal cord. Pre-treatment with spantide depressed the spontaneous flinches of the injected paw in the second phase of the formalin test. At the same time, the up-regulation of NOS was substantially inhibited. CONCLUSION: It might be concluded that substance P played an important role in the up-regulation of NOS in the pericentral canal region of the spinal cord in the formalin test. 相似文献
994.
Endostatin, a 20 kD (184 aa) C-teminal fragment of collagenⅩⅧ, is the most potent inhibitor of tumor angiogenesis described so for. Endostatin was initially isolated from a murine hemangioendothelioma cell line (EOMA). Purified recombinant murine endostatin generated in E. coli bacteria injected as unfolded suspension, inhibited the growth of a varity of metastatic and primary tumors in mice. However, its widespread application has been hampered by difficulties in the large-scale production of the antiangiogenic proteins. The limitation may be resolved by in vivo delivery and expression of the antitangiogenic gene. This review summarized the advances in endostain research in recent years including structure, the mechanism of generating, function and therapy. 相似文献
995.
半干旱区城乡接合部景观镶嵌结构研究--以兰州市西固区为例 总被引:3,自引:3,他引:3
在RS与GIS的技术支持下,以地处西北半干旱区的城乡接合部-兰州市西固区为区域背景,利用景观生态学方法研究了在不同的坡度、高程下景观镶嵌结构的空间布局与空间镶嵌作用的机制。结果显示:随着坡度的增加景观镶嵌结构的多样性指数减小,斑块数量、破碎度先增加后减少,优势度先增加后减少;随着高程的增加,多样性指数,斑块数、破碎度先减少后增加,优势度则相反。景观镶嵌体在坡度与高程的分布上具有一致性,综合坡度与高程分区的景观分形模型模拟结果显示:人类活动影响较小的自然景观类型的复杂性远高于人工景观类型,而稳定性后者高于前者。由此得到以下结论:⑴影响本区景观格局最主要的因素是气候因素;⑵景观格局分布的垂直变化明显;⑶河流廊道在构建本区景观格局中也扮演重要角色;⑷2 类有可能通过改变景观类型的复杂性和影响着自然生态环境。 相似文献
996.
997.
998.
采用RT-PCR和RACE技术,从鹿茸软骨细胞总RNA中扩增克隆了梅花鹿X型胶原(collagen X,colX)全长cDNA序列,并进行了序列特性分析。序列分析结果表明,梅花鹿colX全长cDNA序列为3135nt,其中5′非编码区96nt、3′非编码区1014nt和2022nt的开放阅读框编码674个氨基酸的鹿colX前体蛋白,与牛、猪、犬、人类和小鼠等脊椎动物colX氨基酸序列之间的同源性超过82%。按该基因氨基酸序列构建了进化树,揭示其与牛基因更加同源。 相似文献
999.
1000.
采用常规方法建立杂交瘤细胞株并制备抗犬瘟热病毒(Canine distemper virus,CDV)(Onderstepoort株)核蛋白单克隆抗体(MAb);小鼠腹腔注射阳性克隆生产腹水;以G蛋白亲和层析法进行纯化;用透析法对单抗进行FlTC(异硫氰酸荧光素)标记;Sephadex G-25去除游离荧光素;测定F/P值及荧光抗体工作浓度;以吸收、阻断、抗原交叉试验对荧光抗体进行特异性鉴定.结果表明,获得6株能稳定分泌CDV单克隆抗体的杂交瘤细胞株,选取抗CDV核蛋白的CE3单抗成功地制备了质量较高的荧光抗体. 相似文献