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Congenital bronchobiliary fistula   总被引:1,自引:0,他引:1  
Chang  CC; Giulian  BB 《Radiology》1985,156(1):82
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Kappa-硒化卡拉胶是一含硒有机化合物。ip 9 mg·kg~(-1)·d~(-1)×5d或单次ig 35,70,140mg·kg~(-1)能显著提高乌头碱致大鼠HA的阈剂量,此作用可与Na_2SeO_3 1 mg·kg~(-1)·d~(-1)×5d ip比拟.随着Kappa-硒化卡拉胶ig剂量增加,尚可提高乌头碱所致VE,VT和VF的阈剂量。ip 9mg·kg~(-1)·d~(-1)×5 d或ig 70mg·kg~(-1)能提高BaCl_2致大鼠或哇巴因致豚鼠HA的阈剂量。对BaCl_2致大鼠VF或哇巴因致豚鼠VE的阈剂量,分别在ig70mg·kg~(-1)与140mg·kg~(-1)时有提高,而ipNa_2SeO_3 1 mg·kg~(-1)·d~(-1)×5d无此明显影响。  相似文献   
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A central feature of tumor metastasis is the migration of malignant cells through interstitial tissues and vascular structures as they spread throughout the body. Various components of the extracellular matrix and of basement membranes, consisting of genetically distinct collagens, proteoglycans, and noncollagenous glycoproteins, are known to modulate certain aspects of cell behavior, including cell movement. Serum spreading factor is a glycoprotein component of human serum that is also found in interstitial tissues. Two native forms are seen in human serum, a Mr 65,000 and a Mr 75,000 component. Spreading factor promotes substratum attachment and spreading of diverse cell types, including epithelial and fibroblastic cells, and will affect the growth rate and differentiation of cells in serum-free culture media. Serum spreading factor was shown to promote the directed migration of the following tumor cell lines in modified Boyden chamber assays: murine melanoma K-1735 (clones M2, M4, and 16); human breast carcinoma MCF-7; and human fibrosarcoma HT-1080. The stimulation of movement occurred over a concentration range of 0.5 to 50 micrograms of serum spreading factor per ml with a maximum response between 5 and 10 micrograms/ml. The maximal response varied with the cell line and ranged from 5- to 50-fold greater migration than control. A monoclonal antibody to spreading factor, previously shown to inhibit the attachment and spreading-promoting activity, abrogated this migration response. Experiments using filters that were precoated with spreading factor indicated that cells could migrate on an insolubilized layer of this protein by haptotaxis. Tumor cell migration to spreading factor in vitro suggests a possible role for this protein in the phenotypic behavior of metastatic cells.  相似文献   
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We have examined the actions of a novel xanthine derivative, propentofylline (HWA 285), that has been shown to protect against ischemic brain damage in rats and gerbils, on adenosine receptors (A1 and A2), and on adenosine transporters using several techniques, cells and tissues. Propentofylline and its hydroxylated metabolite A 72 0287 were about 20 times less potent than theophylline in displacing A1-agonist binding to membranes from rat cortex, and A1-antagonist binding to whole DDT, MF-2 smooth muscle cells. A1-agonist binding to adenosine A1-receptors in several brain structures was inhibited in a concentration-dependent manner by A 72 0287 and propentofylline as judged by quantitative autoradiography (IC50-values 300-600 microM in eg striatum and in cortex layer IV). In two functional assays, A1-receptor mediated effects were blocked by propentofylline. A1-receptor-mediated inhibition of cyclic AMP accumulation was virtually abolished by 100 microM propentofylline. The A1-receptor-mediated inhibition of evoked acetylcholine release was also reduced by propentofylline, but in this case the effect is not due exclusively to adenosine receptor antagonism but also to another action since the presynaptic inhibitory effect of carbachol was also inhibited. Adenosine A2-receptors were also antagonized by propentofylline as judged by a concentration-dependent antagonism of A2-agonist-induced cAMP accumulation in human T-leukemia cells (possessing putative A2b-receptors; pA2-value 180 microM compared to 0.26 microM for 8-cpt), and in PC-12 cells (possessing putative A2a-receptors, Ki-value 365 microM). Finally, adenosine transporters were affected by propentofylline and A 72 0287. Thus, [3H]-nitrobenzylthioinosine-binding to guinea-pig cardiac membranes was blocked by propentofylline or A 72 0287 (Ki 270 microM). The present results show that propentofylline and its hydroxylated metabolite can influence adenosine mechanisms in a multitude of ways. How these different actions may contribute to the ability of propentofylline to reduce the magnitude of ischemic damage is discussed.  相似文献   
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1临床资料2003-03/2004-12就诊性病患者100(男68,女32)例;年龄19~60岁;文化程度中学以下78例,大专以上22例;职业个体49例,有工作单位39例,无业12例;病种尖锐湿疣52例、非淋菌性尿道炎20例、淋病18例、梅毒3例、生殖器疱疹7例; 96例经0.5~6.0 mo的治疗康复,4例病情好转. 接诊过程从交谈及肢体语言发现,98%的患者就诊时对病史遮遮掩掩,甚至隐瞒,觉得羞耻,见不得人,愧对家人;68%的患者由于对性病的一知半解,存在有恐惧感、悲观、自责、压抑、焦虑的情绪表现;36%的患者担心家人、同事知道病情而引发一系列家庭、工作问题[1];43%的患者担心病情加重、扩散、传染家人、治疗后复发、未彻底治愈以及治疗费用太高等.  相似文献   
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