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41.
目的探究化疗对小细胞肺癌(small cell lung cancer,SCLC)患者免疫功能的影响。方法选择2013年1月到2018年12月我院收治的95例小细胞肺癌患者为研究对象。患者第一周期、第二周期化疗前采用流式细胞术检测患者外周血淋巴细胞亚群水平,分别按照不同疗效及不同化疗方案对患者外周血淋巴细胞亚群进行比较。结果(1)化疗后,95例患者CD3+、CD4+、CD8+细胞平均值增加,CD19+、γδT细胞平均值减少,差异均有统计学意义(均P<0.05)。(2)化疗后,部分缓解组患者CD3+、CD8+细胞平均值增加,CD19+细胞减少,差异有统计学意义(均P<0.05);病情稳定组和病情进展组患者各细胞水平无显著变化(均P>0.05)。(3)依托泊苷联合顺铂(EP)方案组化疗后患者CD3+、CD8+细胞平均值增多,CD19+细胞减少,差异均有统计学意义(均P<0.05);伊立替康联合顺铂(IP)方案和依托泊苷联合卡铂(EC)方案组化疗后患者各细胞水平无显著变化(均P>0.05)。结论化疗可以调节小细胞肺癌患者的免疫功能,增强细胞免疫,降低体液免疫,其中EC方案对患者细胞免疫的增强作用较为显著。  相似文献   
42.
Melatonin (MLT) is a hormonal substance found in many organisms and can improve plant stress resistance. In this study, the japonica rice variety Y32 and indica rice variety NJ6 were cultivated in hydroponics under different concentrations of CdCl2 at the two-leaf stage. The growth, physiological and biochemical responses of the seedlings and the expression of cadmium (Cd)-related genes under exogenous melatonin (MLT) treatment were assessed. The results indicated that Cd stress destroyed the dynamic balance between reactive oxygen species (ROS) production and removal, resulting in ROS accumulation, membrane lipid peroxidation, and impaired growth and development. Following the application of exogenous MLT to rice seedlings, increases in plant biomass including both underground and above-ground areas were observed. MLT also scavenged the inhibition of superoxide dismutase (SOD) and peroxidase (POD) in a concentration dependent manner in response to Cd stress. Catalase (CAT) activity and malondialdehyde (MDA) expression also decreased following MLT treatment. Amongst the six Cd-related genes assessed, five genes were down-regulated and one was up-regulated in response to MLT treatment. Taken together, these data demonstrate that MLT improves the resilience of rice seedlings at the biochemical, physiological, and molecular levels, and diminishes the damage caused by Cd stress.  相似文献   
43.
Barley (Hordeum vulgare L.) is one of the most Aluminum (Al) sensitive cereal species. In this study, the physiological, biochemical, and molecular response of barley seedlings to Al treatment was examined to gain insight into Al response and tolerance mechanisms. The results showed that superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activity were inhibited to different degrees following Al exposure. The MDA content also significantly increased with increasing Al concentrations. SRAP results indicated significant differences between Al treatments and controls in terms of SRAP profile, and the genomic template stability (GTS) decreased with increasing Al concentration and duration. These integrative results help to elucidate the underlying mechanisms that the barley response to Al toxicity.  相似文献   
44.
The bacterial diversity in fecal samples from the wild pygmy loris was examined with a 16S rDNA clone library and restriction fragment length polymorphism analysis. The clones were classified as Firmicutes (43.1%), Proteobacteria (34.5%), Actinobacteria (5.2%), and Bacteroidetes (17.2%). The 58 different kinds of 16S rDNA sequences were classified into 16 genera and 20 uncultured bacteria. According to phylogenetic analysis, the major genera within the Proteobacteria was Pseudomonas, comprising 13.79% of the analyzed clone sequences. Many of the isolated rDNA sequences did not correspond to known microorganisms, but had high homology to uncultured clones found in human feces. Am. J. Primatol. 72:699–706, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
45.
To compare the role of nitric oxide in an adaptive process to chronic hypoxia, we examined the effects of endogenous nitric oxide synthase inhibition on pulmonary vascular tone in conscious sheep and pigs living at high altitude. Unanesthetized male sheep (n=6) and pigs (n=5), born and residing in the highlands of Qinghai Province, China (2,300–3,000 m a.s.l.) were studied at that altitude. Pulmonary artery pressure (Ppa), pulmonary artery wedge pressure (Pcwp), and cardiac output (CO) were measured. Pulmonary vascular resistance (PVR) was calculated as (PpaPcwp)/CO. Using a climatic chamber, hemodynamic measurements during exposures to atmospheric pressures corresponding to altitudes of 0, 2,300, and 4,500 m a.s.l. were performed with and without NO inhibition, using Nw-nitro-l-argine (NLA; 20 mg kg–1), a potent stereospecific competitive inhibitor of nitric oxide synthase. Ppa and PVR at baseline (2,300 m) and during hypoxic exposure (4,500 m) were significantly higher in pigs than in sheep. After NLA administration, Ppa increased and CO decreased in both animals, resulting in significantly increased PVR at baseline and during hypoxic exposure. However, there were no significant differences in the percent increase in basal or hypoxic PVR after NLA administration between sheep and pigs. We conclude that augmented endogenous NO production could contribute to the regulation of pulmonary vascular tone at high altitude in sheep and pigs. However, it is unlikely that NO is responsible for the different pulmonary vascular tones between sheep and pigs at basal condition at moderately high altitude.Communicated by G. Heldmaier  相似文献   
46.
By using cell wall degrading enzymes, Casparian strips were for the first time isolated from Pinus bungeana needle endodermis. They appeared as a fine network, similar to those isolated from roots. Fourier transform infrared spectroscopic analysis provided evidence that the Casparian strips were impregnated with lignin, suberin, cellulose and cell wall proteins.  相似文献   
47.
Deficiency of ABCA1 causes high density lipoprotein deficiency and macrophage foam cell formation in Tangier disease. ABCA1 was also postulated to mediate the secretion of IL-1beta from monocytes and macrophages. We investigated the contribution of ABCA1 to IL-1beta secretion from human monocytes and macrophages of normal donors and Tangier disease patients. Neither an anti-ABCA1 antisense oligonucleotide nor ABCA1 deficiency interfered with LPS-induced secretion of IL-1beta from full blood or freshly isolated monocytes. By contrast, anti-ABCA1 antisense oligonucleotides decreased the LPS-induced secretion of IL-beta from macrophages by 30-50%. The secretion of the precursor pro-IL-1beta and TNFalpha was not inhibited. Compared to normal macrophages, LPS-stimulated Tangier disease macrophages secreted less IL-1beta relative to TNFalpha. Also the spontaneous secretion of IL-1beta by Tangier macrophages was lower than by control cells. We conclude that IL-1beta is secreted from monocytes by an ABCA1-independent pathway and from macrophages by ABCA1-dependent and -independent pathways.  相似文献   
48.
The present study characterizes the interaction between the Raf-1 kinase domain and MEK1 and examines whether the magnitude of their interaction correlates to the ability of Raf to phosphorylate MEK1. Here we show that the minimal domain required for the Raf kinase activity starts from tryptophan 342. Maximal binding of the Raf kinase domain to MEK1 and its kinase activity are achieved upon phosphorylation of the region (338)SSYY(341) in response to 4beta-12-O-tetradecanoylphorbol-13-acetate (TPA), or mutation of Y340Y341 to aspartic acids. Conversely, the TPA-stimulated MEK binding and kinase activity are diminished when this region is deleted or Ser(338) and Ser(339) are mutated to alanines. We also show that the integrity of the Raf ATP-binding site is necessary for the interaction between Raf-1 and MEK1. Furthermore, two MEK-binding sites are identified; the first is localized between amino acids 325 and 349, and the second is within the region between amino acids 350 and 648. Separately, the binding of each site to MEK1 is weak, but in a cis context, they give rise to a much stronger association, which can be further stimulated by TPA. Finally, we find that tryptophan 342, which is conserved among the Raf family and other protein kinases, is essential for the Ser(338) phosphorylation of the full-length Raf and its binding to MEK1. Taken together, our results indicate that the phosphorylation of Ser(338) and Tyr(341) on Raf exerts an important effect on reconfiguring the two MEK-binding sites. As a result, these two sites coordinate to form a high affinity MEK-binding epitope, leading to a marked increase in Raf kinase activity.  相似文献   
49.
大青沟残遗森林植物群落特点及种间联结性研究   总被引:9,自引:1,他引:8  
大青沟残遗森林植物群落分布于科尔沁沙地,是一个非常特殊的森林群落类型。在野外调查的基础上,分析了其群落学特点,并分析了对群落整体功能有重要影响的31个乔、灌木种类的种间联结性。结果表明,大青沟落叶阔叶林主要由具复叶、小叶和中叶的落叶大高位芽植物和中高位芽植物所组成。植物种类丰富,计有维管植物106科,359属,709种,约占整个内蒙古植物种数的三分之一。主要木本植物之间发生联结的情况较多,既有正联结,也有负联结。  相似文献   
50.
常燕玲  梁晓琴  黄艳  潘立卫  侯萍  任晨阳  李俊 《广西植物》2023,43(11):2113-2119
为研究大萼香茶菜(Isodon macrocalyx )的化学成分,该文采用硅胶、ODS、Sephadex LH-20、反相C18半制备高效液相等色谱方法对大萼香茶菜地上部分进行分离纯化,并利用1H NMR、13C NMR和HR-ESI-MS等波谱数据,以及结合 参考文献,鉴定了这些化合物的结构。结果表明:从大萼香茶菜地上部分分离得到13个二萜,它们分别是19-羟基陶塔酚(1)、macrophynin E(2)、inumakoic acid(3)、inumakiol D(4)、4β-carboxy-19-nortotarol(5)、(-)-lambertic acid(6)、2-oxo-5-fagonene(7)、isodoterniofiln B(8)、长管贝壳杉素E(9)、长管香茶菜素A(10)、牛尾草素H(11)、16S-dihydrolongikaurin A(12)和ent-3S,16S,17-trihydroxy-kauran-2-one(13)。所有得到的二萜均为首次从该植物中分离得到。  相似文献   
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