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81.
Monitoring vegetation recovery after China’s May 2008 Wenchuan earthquake using Landsat TM time-series data: a case study in Mao County 总被引:2,自引:0,他引:2
Tao Lu Hongcheng Zeng Yan Luo Qian Wang Fusun Shi Geng Sun Yan Wu Ning Wu 《Ecological Research》2012,27(5):955-966
The Wenchuan earthquake (Richter scale 8) on 12 May 2008 in southwestern China caused widespread ecosystem damage in the Longmenshan area. It is important to evaluate natural vegetation recovery processes and provide basic information on ecological aspects of the recovering environment after the earthquake. To circumvent the weather limits of remote sensing in the Wenchuan earthquake-hit areas, and to meet the need for regional observation analyses, three Landsat TM images pre- and post-earthquake in Mao County were used for analysis. Post-earthquake normalized difference vegetation index (NDVI) values were compared to pre-earthquake values with an NDVI-based index differencing method to determine the extent to which the vegetation was damaged in relation to the pre-earthquake pattern, and the rate of recovery was evaluated. The spatial characteristics of vegetation loss and natural recovery patterns were analyzed in relation to elevation, slope and aspect. The results indicated that severely damaged sites occurred mainly in river valleys, within a range of 1,500?C2,500?m elevation and on slopes of 25?C55°. The distance from rivers, rather than the distance from active faults, controls the damage patterns. After 1?year of natural regeneration, 36?% of the destroyed areas showed a decrease in NDVI value, 28.8?% showed very little change, 19.1?% showed an increase, and 16.1?% also increased with a recovery rate greater than 100?%. Moreover, there is a good correlation between recovery rate and both slope and elevation, but recovery patterns in the damaged area are complicated. Our results indicate that natural recovery in this arid valley is a slow process. 相似文献
82.
Genetic variation within and among populations of a wild rice Oryza granulata from China detected by RAPD and ISSR markers 总被引:37,自引:0,他引:37
W. Qian S. Ge D.-Y. Hong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(2-3):440-449
Genetic variation within and between five populations of Oryza granulata from two regions of China was investigated using RAPD (random amplified polymorphic DNA) and ISSR (inter-simple sequence
repeat amplification) markers. Twenty RAPD primers used in this study amplified 199 reproducible bands with 61 (30.65%) polymorphic;
and 12 ISSR primers amplified 113 bands with 52 (46.02%) polymorphic. Both RAPD and ISSR analyses revealed a low level of
genetic diversity in wild populations of O. granulata. Furthermore, analysis of molecular variance (AMOVA) was used to apportion the variation within and between populations both
within and between regions. As the RAPD markers revealed, 73.85% of the total genetic diversity resided between the two regions,
whereas only 19.45% and 6.70% were present between populations within regions and within a population respectively. Similarly,
it was shown by ISSR markers that a great amount of variation (49.26%) occurred between the two regions, with only 38.07%
and 12.66% between populations within regions and within a population respectively. Both the results of a UPGMA cluster, based
on Jaccard coefficients, and pairwise distance analysis agree with that of the AMOVA partition. This is the first report of
the partitioning of genetic variability within and among populations of O. granulata at the DNA level, which is in general agreement with a recent study on the same species in China using allozyme analysis.
Our results also indicated that the percentage of polymorphic bands (PPB) detected by ISSR is higher than that detected by
RAPD. It seems that ISSR is superior to RAPD in terms of the polymorphism detected and the amplification reproducibility.
Received: 29 March 2000 / Accepted: 15 May 2000 相似文献
83.
Qian Jia HongTao Wu XingJun Zhou Jian Gao Wei Zhao JouDi Aziz JingShuang Wei Lihua Hou Shuyin Wu Ying Zhang XiangFeng Dong YanMin Huang WeiYuan Jin HongJie Zhu XinHui Zhao ChunHua Huang LiPing Xing Liwen Li Jun Ma Xiyan Liu Ran Tao ShuaiDong Ye YiGao Song LingLing Song GuanPing Chen ChunLing Du XueTing Zhang Bo Li YanTao Wang Wei Yang Gilbert Rishton YuYang Teng GouQing Leng LuanFeng Li WenXian Liu LiJun Cheng QiuBo Liang ZhengWu Li XiuQin Zhang Yajun Zuo Wei Chen Huicheng Li Matthew Hui 《中国科学:生命科学英文版》2010,53(1):94-100
High mammalian gene expression was obtained for more than twenty different proteins in different cell types by just a few laboratory scale stable gene transfections for each protein. The stable expression vectors were constructed by inserting a naturally-occurring 1.006 kb or a synthetic 0.733 kb DNA fragment (including intron) of extremely GC-rich at the 5′ or/and 3′ flanking regions of these protein genes or their gene promoters. This experiment is the first experimental evidence showing that a non-coding extremely GC-rich DNA fragment is a super “chromatin opening element” and plays an important role in mammalian gene expression. This experiment has further indicated that chromatin-based regulation of mammalian gene expression is at least partially embedded in DNA primary structure, namely DNA GC-content. 相似文献
84.
Kong X Zhang C Jin X Wu X Zhang S Zhong Z Feng Q Liu T Yuan H 《BioFactors (Oxford, England)》2011,37(4):323-327
The objective of this study is to observe the effect of high-mobility group protein B1 A Box (HMGB1 A) box on lung injury in mice with acute pancreatitis and its effect on the level of high-mobility group protein B1 (HMGB1) in lung, to explore the mechanism. A total of 60 male Institute of Cancer Research mice were randomly divided into control group (n = 30) and treatment group (n = 30). Severe acute pancreatitis mice model was induced by 20% L-Arg intraperitoneal injection. The recombination HMGB1 A box was used in treatment after modeling. All the mice were killed under anesthesia at 24 and 48 h after the modeling injection. The level of HMGB1 and activity of myeloperoxidase (MPO) in lung were measured. The pathological changes of lung were observed. The level of HMGB1 in lung of A box treatment group decreased more significantly 24 h and 48 h after modeling compared with control group. The activity of MPO in lung of A box treatment group decreased more significantly 24 h after modeling compared with control group. The lung tissue pathologic score of A box treatment group decreased more significantly 48 h after modeling compared with control group. HMGB1 expression levels in the lungs were positively related to histological score of injured lung in acute pancreatitis. It indicates that HMGB1 A box is remarkably protective to lung injury induced by acute pancreatitis. 相似文献
85.
86.
Ma YM Tao RY Liu Q Li J Tian JY Zhang XL Xiao ZY Ye F 《Molecular and cellular biochemistry》2011,357(1-2):65-72
PTP1B is a negative regulator of insulin signaling pathway. This study investigated the effects of compound CCF06240, a PTP1B inhibitor, on insulin sensitivity and lipid metabolic abnormalities in vivo and in vitro, respectively. The insulin resistant IRM mouse model was induced by HFD. The responses to insulin were determined by OGTT, ITT, and hyperinsulinemic-euglycemic clamp test. The body weight and the levels of serum TC and TG were measured to estimate the lipid metabolism in vivo. Recombinant human GST-PTP1B protein was used to measure the inhibition of CCF06240 on PTP1B activity. The hepatocyte lipid accumulation was induced by high concentrations of FFA and insulin in HepG(2) cells, and evaluated by the Oil Red O method. In IRM mice, the insulin resistance was improved; the body weight and the levels of TC and TG were also reduced by oral CCF06240 administration. In lipid accumulated model cells, CCF06240 was found to reverse the increased PTP1B activity, enhance the insulin-induced tyrosine phosphorylation in insulin signaling pathway, attenuate the FFA-insulin-induced cellular lipid accumulation, and down-regulate the expressions of genes related fatty acid synthesis. These results demonstrated that the PTP1B inhibitor, compound CCF06240, could increase insulin sensitivity through the regulation of insulin signaling pathway, and decrease FFA-insulin-induced hepatocytes lipid accumulation by reducing fatty acid syntheses. 相似文献
87.
多重连接探针扩增方法在假肥大性肌营养不良产前基因诊断中的应用 总被引:3,自引:0,他引:3
假肥大性肌营养不良(Duchenne/Becker muscular dystrophy, DMD/BMD)是一种由于DMD基因突变导致的X连锁隐性致死性遗传病。目前没有有效的治疗方法。为建立一种既可以对携带者进行检测又可以进行产前基因诊断的方法, 文章联合应用多重连接探针扩增技术(Multiplex ligation-dependent probe amplification, MLPA)和短串联重复序列(Short tandem repeats , STR)为遗传标记连锁分析的方法对26例有高风险再生育患儿的假肥大性肌营养不良家系的孕妇通过羊水穿刺进行产前基因诊断。26例进行产前基因诊断的羊水标本中有7例诊断为男性患儿, 4例诊断为女性携带者。MLPA可以作为筛查DMD基因缺失和重复突变的首选方法。联合应用MLPA和STR连锁分析, 可以提高假肥大性肌营养不良的产前基因诊断率。 相似文献
88.
89.
90.
Hua Zhou Chunlei Yao Ao Bian Jun Qian Xiufen Zhao Yanting Zhao Weiwei Wang Changying Xing 《Molecular and cellular biochemistry》2014,391(1-2):21-25
Podocyte injury may contribute to the pathogenesis of diabetic nephropathy (DN), but the underlying mechanism of hyperglycemia induced podocyte damage is not fully understood. The Ras GTPase-activating-like protein IQGAP1 is associated to the slit diaphragm proteins and the actin cytoskeleton in podocyte. Here, we studied IQGAP1 expression alterations in human DN biopsies and extracellular signal-regulated kinase (ERK)-dependent pathways of IQGAP1 expression in podocyte under high glucose (HG) media. In vivo, analysis of renal biopsies from patients with DN revealed a significant reduction in IQGAP1 expression compared to controls. In vitro, IQGAP1 mRNA and protein expression were observed to decline under HG media at 48 h. But phosphorylation of ERK1/2 was activated under HG media at 24 h and 48 h. However, HG-induced downregulation of IQGAP1 protein was attenuated by specific ERK1/2 activation inhibitor PD98059. Taken together, these results highlight the importance of IQGAP1 in DN, and suggest that IQGAP1 expression in podocyte under HG media is modulated by the ERK1/2 pathway, which may lead to the future development of therapies targeting IQGAP1 dysfunction in podocytes in DN. 相似文献