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1.
Summary Human recombinant interleukin-1 (HrIL-1) inhibited WEHI-3B cell growth in a dose-related manner (10–10000 U/ml). Prostaglandin E2 at high concentrations (1000 ng/ml) also inhibited cell growth. When added together, HrIL-1 and prostaglandin E2 inhibited WEHI-3B growth in a synergistic manner (HrIL-1 concentrations of 10–10000 U/ml and prostaglandin E2 concentrations of 10–1000 ng/ml). In contrast to the effects of the cyclooxygenase metabolite of arachidonic acid leukotriene C4, a lipoxygenase metabolite, reversed the cytostatic action of HrIL-1.  相似文献   
2.
描述了产自四川自贡大山铺恐龙化石坑中的三件龟甲标本,命名为一新属新种—周氏四川龟(Sichuanchelyschowigen.etsp.nov.)。该属以椎盾极横宽,中部缘盾极狭长为主要特征,它代表了成渝龟科中一类较特别的类型。  相似文献   
3.
In the carrageenin-induced granuloma of rats the inflammatory tissue growth and macrophage invasion on the one hand and the cyclic-AMP content of the macrophages on the other, display opposite directional changes. Macrophages, isolated from this tissue at different stages of inflammation, were used to examine the effect of prostaglandin E2 on intracellular levels of c-AMP. It appears that during infiltration of the macrophages into the inflammatory tissue, the sensitivity of adenylate cyclase to activation by PGE2 increases. Arguments are presented that these observations made , are in direct relevance to the previously described anti-inflammatory effect of PGE on granuloma tissue .  相似文献   
4.
1. Predation‐exclusion experiments have highlighted that top‐down control is pervasive in terrestrial communities, but most of these experiments are simplistic in that they only excluded a single group of predators and the effect of removal was evaluated on a few species from the community. The main goal of our study was to experimentally establish the relative effects of ants and birds on the same arthropod assemblage of canopy trees. 2. We conducted 1‐year long manipulative experiments in an organic citrus grove intended to quantify the independent effects of bird and ant predators on the abundance of arthropods. Birds were excluded with plastic nets whereas ants were excluded with sticky barriers on the trunks. The sticky barrier also excluded other ground dwelling insects, like the European earwig Forficula auricularia L. 3. Both the exclusion of ants and birds affected the arthropod community of the citrus canopies, but the exclusion of ants was far more important than the exclusion of birds. Indeed, almost all groups of arthropods had higher abundance in ant‐excluded than in control trees, whereas only dermapterans were more abundant in bird‐excluded than in control trees. A more detailed analysis conducted on spiders also showed that the effect of ant exclusion was limited to a few families rather than being widespread over the entire diverse spectrum of spiders. 4. Our results suggest that the relative importance of vertebrate and invertebrate predators in regulating arthropod populations largely depends on the nature of the predator–prey system.  相似文献   
5.
好氧反硝化生物脱氮技术的研究进展   总被引:4,自引:1,他引:3  
好氧反硝化生物脱氮技术自提出以来,凭借能实现同步硝化反硝化、节省基建投资及运行费用等诸多优点,受到国内外环境领域学者的广泛关注。本文首先总结了近年来好氧反硝化菌种的筛选分离情况,以及环境因子对好氧反硝化菌脱氮效能的影响,包括溶解氧(dissolved oxygen,DO)、碳氮比(C/N)、温度等。然后深入探讨了好氧反硝化生物脱氮技术的原理,好氧反硝化过程中的关键功能基因及酶,同时介绍了分子生物技术在好氧反硝化研究过程中的应用,以及好氧反硝化生物脱氮技术在实际应用方面的研究现状。最后,基于目前的研究瓶颈问题,对未来好氧反硝化生物脱氮技术的研究方向提出了科学展望。  相似文献   
6.
鄂西大蓟根的化学成分的研究   总被引:2,自引:0,他引:2  
本题对菊科蓟属植物鄂西大蓟根Cirsium henryi的化学成分进行系统研究。采用硅胶柱色谱法分离了五个单体成分并以光谱分析法鉴定它们的结构:乙酰丁香酸(p-Hydroxycinnamic acid,1),原儿茶酸(protocate-chuic acid,2),香草酸(vanillic acid,3),二羟丙基软脂酸酯(2,3-dihydroxypropyl hexadecanoate,4)和胡萝卜苷(glucoraphenin,5)。这些化合物均为首次从该植物中分离得到。  相似文献   
7.
NR4A nuclear orphan receptors: protective in vascular disease?   总被引:1,自引:0,他引:1  
PURPOSE OF REVIEW: The nuclear orphan receptors Nur77 (NR4A1), Nurr1 (NR4A2) and NOR-1 (NR4A3) are known to be involved in T-cell apoptosis, brain development, and the hypothalamic-pituitary-adrenal axis. Here, we review our current understanding of the NR4A nuclear receptors in processes that are relevant to vascular disease. RECENT FINDINGS: NR4A nuclear receptors have recently been described to play a role in metabolism by regulating gluconeogenesis, lipolysis, energy expenditure, and adipogenesis. The function of NR4A nuclear receptors has also extensively been investigated in cells crucial in vascular lesion formation, such as macrophages, endothelial cells and smooth muscle cells. SUMMARY: The involvement of NR4A nuclear receptors in both metabolism and in processes in the vessel wall supports a substantial role for NR4A nuclear receptors in the development of vascular disease.  相似文献   
8.
目的:探讨在B超引导下子宫内膜消融术治疗更年期功血的效果。方法:扩张宫颈至6.5号,吸宫,在B超监视下由子宫右前壁始向外刮凝,依次顺时针方向刮凝宫腔2周。结果:治愈31例(60.8%),有效19例(37.3%),好转1例(1.9%),无效0例。结论:电凝刀子宫内膜消融术与其他更年期功血治疗方法相比,消融的范围及深度由B超监视,安全性高,创伤小,不开刀,恢复快,并且治愈率高,更容易在临床上推广。  相似文献   
9.
目的:探讨反应性血小板增高患者凝血指标及血小板聚集功能指标变化规律。方法:143例血小板反应性增高患者和65例对照者同时检测血小板聚集功能、抗凝血酶活性(AT-Ⅲ)、凝血酶原时间(PT)和活化部分凝血活酶时间(APTT),并统计分析。结果:血小板反应性增高常见于肿瘤、肺炎、外伤患者;血小板反应性增高组患者AT-Ⅲ、PT和APTT与对照组无差异,但患者血小板聚集功能显著高于对照组。结论:血小板反应性增高患者血小板聚集功能增强,建议定期监测血小板聚集功能,必要时用抗血小板聚集药预防。  相似文献   
10.
Summary Indomethacin enhanced macrophage cytostasis against MOPC-315 tumor cells in vitro. The effect of indomethacin was inhibited by prostaglandin E2 and by the lipoxygenase inhibitor nordihydroguaiaretic acid. Prostaglandin E2 and nordihydroguaiaretic acid also inhibited indomethacin stimulation of macrophage thymidine incorporation. Indomethacin inhibited macrophage prostaglandin E2 formation and stimulated leukotriene B4 synthesis. Nordihydroguaiaretic acid inhibited leukotriene B4 production. Our data indicate that eicosanoids play a role in regulating macrophage cytostasis.  相似文献   
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