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101.
热带季节雨林林窗边缘不同热力作用面热力效应的季节变化特征 总被引:4,自引:0,他引:4
通过对热带季节雨林雾凉季和湿热季昼间林窗区域不同热力作用面的热力效应初步分析,指出在西双版纳,不论是雾凉季还是湿热季,热带季节雨林林窗边缘壁面均具有不可忽视的热力作用,且由于受林缘树木的影响,热力效应较强的东侧,北侧林缘壁面最大区域出现位置高于次生林林窗,而强度小于次生林林窗,显示了林窗边缘壁面的热力效应除与太阳高度角,太阳辐射的时间长短和强度有关之外,林窗边缘树木高度也是不可忽视的因子,其结果可为进一步研究林窗小气候形成机制提供研究基础,为研究林窗更新及生物多样性问题提供科学参考。 相似文献
102.
Molecular Biology Reports - Interleukin 35 (IL35) has been reported to play a role in acute lung injury (ALI); however, the current results regarding the relationship between IL35 and ALI are... 相似文献
103.
Jiang XS Zhou H Zhang L Sheng QH Li SJ Li L Hao P Li YX Xia QC Wu JR Zeng R 《Molecular & cellular proteomics : MCP》2004,3(5):441-455
Four fractions from rat liver (a crude mitochondria (CM) and cytosol (C) fraction obtained with differential centrifugation, a purified mitochondrial (PM) fraction obtained with nycodenz density gradient centrifugation, and a total liver (TL) fraction) were analyzed with two-dimensional liquid chromatography tandem mass spectrometry analysis. A total of 564 rat proteins were identified and were bioinformatically annotated according to their physicochemical characteristics and functions. While most extreme alkaline ribosomal proteins were identified in the TL fraction, the C fraction mainly included neutral enzymes and the PM fraction enriched alkaline proteins and proteins with electron transfer activity or oxygen binding activity. Such characteristics were more apparent in proteins identified only in the TL, C, or PM fraction. The Swiss-Prot annotation and the bioinformatic prediction results proved that the C and PM fractions had enriched cytoplasmic or mitochondrial proteins, respectively. Combination usage of subcellular fractionation with two-dimensional liquid chromatography tandem mass spectrometry was proved to be a high-throughput, sensitive, and effective analytical approach for subcellular proteomics research. Using such a strategy, we have constructed the largest proteome database to date for rat liver (564 rat proteins) and its cytosol (222 rat proteins) and mitochondrial fractions (227 rat proteins). Moreover, the 352 proteins with Swiss-Prot subcellular location annotation in the 564 identified proteins were used as an actual subcellular proteome dataset to evaluate the widely used bioinformatics tools such as PSORT, TargetP, TMHMM, and GRAVY. 相似文献
104.
Xia Jun Hao Xianzhe Wang Tangang Li Huiqin Shi Xiaojuan Liu Yongchang Luo Honghai 《Journal of Plant Growth Regulation》2023,42(1):319-334
Journal of Plant Growth Regulation - Exogenous substances play an important role in the response of cotton to low-temperature conditions during the germination stage, but little is known about the... 相似文献
105.
106.
<正> 在用二甲亚砜(DMSO)诱导人急性早幼粒细胞性白血病细胞系(HL-60 Cell)沿粒系统分化成熟的实验基础上,我们用受体荧光标记技术和荧光分光光度法,进一步观察了HL-60细胞诱导分化期间,细胞膜流动性动态降低对膜上伴刀豆球蛋白(ConA)受体结合量的影响。 相似文献
107.
Presenilin couples the paired phosphorylation of beta-catenin independent of axin: implications for beta-catenin activation in tumorigenesis 总被引:8,自引:0,他引:8
The Alzheimer's disease-linked gene presenilin 1 (PS1) is required for intramembrane proteolysis of APP and Notch. In addition, recent observations strongly implicate PS1 as a negative regulator of the Wnt/beta-catenin signaling pathway, although the mechanism underlying this activity is unknown. Here, we show that presenilin functions as a scaffold that rapidly couples beta-catenin phosphorylation through two sequential kinase activities independent of the Wnt-regulated Axin/CK1alpha complex. Thus, presenilin deficiency results in increased beta-catenin stability in vitro and in vivo by disconnecting the stepwise phosphorylation of beta-catenin, both in the presence and absence of Wnt stimulation. These findings highlight an aspect of beta-catenin regulation outside of the canonical Wnt-regulated pathway and a function of presenilin separate from intramembrane proteolysis. 相似文献
108.
109.
Ming Xia Qian Ding Zhidan Zhang Qinggen Feng 《Cellular and molecular neurobiology》2017,37(6):1105-1114
Remote limb ischemic preconditioning (RIPC) is a clinically feasible strategy to protect against ischemia/reperfusion injury, but the knowledge concerning the mechanism underlying RIPC is scarce. This study was performed to examine the effect of RIPC on brain tissue suffering from ischemia challenge and explore its underlying mechanism in a rat model. The animals were divided into four groups: Sham, middle cerebral artery occlusion (MCAO), RIPC, and MCAO+RIPC. We found that previous exposure to RIPC significantly attenuated neurological dysfunction and lessened brain edema in MCAO+RIPC group. Moreover, other important events were observed in MCAO+RIPC group, including substantial decrements in the concentrations of oxidative response indicators [malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), and protein carbonyl], significant reductions in levels of inflammation mediators [myeloperoxidase (MPO), tumor necrosis factor-a (TNF-a), interleukin-1β (IL-1β), and IL-6], and significant decline in neuronal apoptosis revealed by a smaller number of TUNEL-positive cells. Interestingly, both MCAO and RIPC groups exhibited meaningful elevations in the levels of HIF-1a, HSP70, and AMP-activated protein kinase (AMPK) compared to Sham group, and previous exposure to RIPC further elevated the levels of HIF-1a, HSP70, and AMPK in MCAO+RIPC group. Furthermore, the administration of YC-1 (HIF-1 inhibitor), 8-bAMP (AMPK inhibitor), and Quercetin (HSP70 inhibitor) to MCAO+RIPC rats demonstrated that HIF-1α/AMPK/HSP70 was involved in RIPC-mediated protection against cerebral ischemia. 相似文献
110.
用简化的Kohn氏碱洗脱法,观察了光敏剂血卟啉衍生物(HPD)对小鼠S-180肿瘤细胞DNA单链断裂及其重接修复的影响。激光HPD能导致S-180细胞DNA单链断裂明显增加,而且这种断裂随着保温时间的延长,继续增多。在本实验条件下没有观察到HPD对X线的增敏作用,HPD不能增加X线所致的DNA单链断裂,也不能影响其重接。单链断裂重接动力学的实验进一步证明了这个论点。 相似文献