赤峰市松山区土地利用动态变化及其原因分析   总被引：8，自引：6，他引：8  

贾宝全王成  马玉峰 《干旱区研究》2004,21(3):235-239

以TM遥感资料为信息源 ,利用 3S技术手段 ,对内蒙古自治区赤峰市松山区 1987,1993,2 0 0 0年的土地利用变化进行了分析。结果表明 ,在不同年度内 ,其主要的土地利用类型为耕地、草地和林地。土地利用类型的总量变化也以这 3种土地利用类型和建设用地变化最大。而从年变化速率看 ,1987- 2 0 0 0年 ,以建设用地的增加和未利用土地类型的减少最为快速。从土地利用类型转化的方向看 ,以耕地、草地和林地相互之间的转化最为频繁。从土地利用类型的空间稳定性看 ,耕地的稳定性最高 ,其次为草地 ;而最不稳定的土地利用类型为未利用土地。利用相关分析所作的土地利用变化动因显示 ,该地区土地利用变化的驱动因素主要是社会与经济因素 ,其中以总人口、农业总产值、粮食作物产量总计、农牧民人均纯收入、化肥使用面积和化肥实物量等因子的作用最大 ,而自然因素对该地区土地利用变化的影响极小。  相似文献   

金昌水资源特点及供需平衡研究   总被引：3，自引：0，他引：3  

朱高峰  马金珠  苏永红  李相虎 《干旱区资源与环境》2004,(Z2)

本文通过建立金昌市人口与牲畜增长规律 ,第二、三产业的GDP增长率规律数学模型 ,计算出在长时间序列中的用水量持续增长状况及根据金昌市农业节水技术和城市生态规划 ,得到农业、生态用水量规划数据。根据水量平衡原理 ,分析了金昌市未来水量供需平衡问题 ,对指导金昌水资源利用 ,具有一定的现实意义。  相似文献   

Antiproliferative effect of c-myc antisense oligonucleotide in rat thymus lymphocytes     

LIU Ying-ge  QI Hao-wen  LI Huan-zhang  SU Ming-quan  YU Wen-bin  MA Yue-yun 《园艺学报》2004,20(5):745-747

AIM: To observe the antiproliferative effect of c-myc antisense oligonucleotide in rat thymus lymphocytes. METHODS: Rat thymus lymphocytes were separated by Ficoll-Urografin density gradient centrifugation. Lipofectin was used to introduce antisense, sense and mismatched oligonucleotides for c-myc to rat thymus lymphocytes. The antiproliferative effect was assayed by incorporation of [³H]-TdR and MTS cell proliferation assay. TR-PCR was used to detect the expression of c-myc mRNA. RESULTS: c-myc antisense oligonucleotide inhibited ratthymus lymphocytes proliferation[(0.14±0.03)A vs(0.32±0.16)A,P<0.05],but this ef ect had no relationship with the concentration of c-myc antisense oligonucleot ide.c-myc antisense oligonucleotide decreased the expression of c-myc mRNA in rat thymus lymphocytes. CONCLUSION: c-myc antisense oligonucleotide inhibited rat thymus lymphocyte proliferation.  相似文献   

Proteomic analysis of the effects of tumor necrosis factor-α on endothelial cells     

L&#  Jun-ping  WANG Shu-ren  MA Zeng-chun  WANG Sheng-qi 《园艺学报》2004,20(7):1121-1125

AIM: To investigate the affected proteins by tumor necrosis factor (TNF)-α in endothelial cells, and further explore the potential molecular mechanism of TNF-α on endothelial cells. METHODS: Nitric oxide (NO) production in the cultured human umbilical vein endothelial cells (HUVECs) was measured by a NO assay kit. Proteomic alterations were analyzed using two-dimensional electrophoresis, and peptide mass fingerprinting with matrix-assisted laser desorption/ionization-time of flight mass spectrometry. RESULTS: NO production in HUVECs decreased significantly after TNF-α treatement. Proteomics analysis showed 21 protein spots were changed including 9 spots that were increased and 11 spots that were decreased after TNF-α stimulation, and 1 spot was only detected in TNF-α activated cell gels. CONCLUSIONS: Decreased the expression of ecNOS by TNF-α might result in decreased NO production. Up-regulated MAP/ERK kinase 3 expression might imply that TNF-α activates the expression of adhesion molecules. Cytoskeletal protein actin is also involved in TNF-α injuried HUVECs. Proteomic analysis can find some clues for identifying new potential target of TNF-α.  相似文献   

Changes of Ca^2＋ activated potassium channels and cellular-proliferation in autogenous vein grafts     

Changes of Ca  SONG Sheng-yun  MA Bao-an  FAN Qing-yu 《园艺学报》2004,20(4):575-579

AIM: To investigate changes of Ca^2＋ activated potassium channels (K_Ca) in autogenous vein grafts. METHODS: The contraction of venous ring was measured by means of perfusion in vitro. The intimal proliferation and proliferation of cultured smooth muscle cells (vascular smooth muscle cells, VSMCs) were observed by the means of computerised image analysis and MTT method, respectively. Furthermore, whole cell mode of patch clamp was used to record K_Ca of VSMCs isolated from autogenous vein grafts. RESULTS: 1 week after transplantation there were no significant differences of contraction and intimal relative thickness between autogenous vein grafts and control. Contraction and intimal relative thickness of autogenous vein graft were significantly increased 2 weeks after transplantation (P＜0.05, n=8 vs control), and they were more enhanced 4 weeks after vein transplantation (P＜0.01, n=8 vs control). TEA (blocker of Ca^2＋ activated potassium channels) increased MTT A₄₉₀ value of VSMCs from femoral vein in a dose-dependent manner (P＜0.05, n=8). K_Ca current density was significantly attenuated in VSMCs from autogenous vein grafts 1-4 weeks after transplantation (P＜0.05, n=5). CONCLUSION: K_Ca was inhibited in autogenous vein graft, which accounted for vasospasm and intimal proliferation.  相似文献   

Influence of irbesarten on renal hypertrophy in streptozotocin-induced diabetic rats LIU Bi-cheng,LUO Dong-dong,ZHANG Xiao-liang.     

SUN Zi-lin  MA Kun-ling  ZHOU Qiu-gen 《园艺学报》2004,20(11):2086-2089

AIM: To investigate the influence of irbesartan (Irb), a new angiotensin II receptor 1 antagonist, on renal hypertrophy in streptozotocin (STZ)-induced diabetic rats. METHODS: Sprague-Dawley (SD) rats were randomly divided into three groups: normal group (Group N, n=7), diabetic group (Group DN, n=6) and irbesartan treated group (Group DNI, n=7). In the experimental group, after the rats subjected to uninephrectomy, STZ was given by peritoneally injection at bolus dose of 50 mg/kg to induce diabetes. Blood glucose (BG), body weight (BW), urinary albumin excretion (Ualb), 24 hour proteinuria (24 h Upro) were measured at week 4, 8, 12, respectively. By the end of experiment at week 12, creatinine clearance (Ccr), kidney weight (KW), indicator of renal hypertrophy (KW/BW), renal total protein content (RTP), glomerular area (AG) and glomerular volume (VG) as well as glomerular basement membrane (GBM) were determined by semi-quantitative pathology technique. RESULTS: It was showed that there was no significant difference in BG between group DN and DNI, while Irb significantly reduced the increasing of Ualb, 24 h Upro in diabetic rats compared to control group (P＜0.01, respectively). Furthermore, Irb markedly inhibited the increasing of KW, KW/BW, RTP, A_G, V_G in diabetic rats (P＜0.05, P＜0.01, respectively). Of interest, Irb significantly prevented the increasing of GBM in diabetic rats. CONCLUSION: Irb exerts its early renal protective action by reducing proteinuria and inhibiting renal hypertrophy as well as the thickening of GBM.  相似文献   

披碱草和野大麦杂种F1与BC1F1代的生物学及农艺特性研究     

李造哲  于卓  马青枝  王俊杰 《中国草地学报》2004,26(5):9-14

对披碱草和野大麦及其杂种F1与BC1F1代的生物学及农艺特性进行了分析比较。结果表明,亲本野大麦生长发育节律较快,较早地开花结实,果后营养期较长,生育期74d,生长天数达206d,具有很强的分蘖能力;披碱草生长发育节律较慢,生育期124d,生长天数193d;杂种F1的生长天数介于双亲之间,生长动态偏向亲本披碱草,分蘖能力介于双亲之间;BC1F1代生长发育节律较F1代提早,不同株系生长天数不同,生长动态偏向轮回亲本野大麦,分蘖能力有较大的变异。杂种F1代表现出较强的杂种优势,BC1F1代产草量较F1代有所降低,不同株系间存在明显的差异。总体上,BC1F1代的生产性能倾向于轮回亲本野大麦。  相似文献   

大肠杆菌新型菌毛(F1987)的基因定位     

房海  陈翠珍  于凤鸣  张晓君  巩元芳  马建军 《中国兽医学报》2004,24(6):558-560

对动物产肠毒素性大肠杆菌 (ETEC)的一种新型菌毛 (F1987)进行了相应基因的定位研究 ,通过对表达该新型菌毛 (F1987)相应 ETEC菌株的培养、质粒提取、对大肠杆菌受体菌株 DH5α的转化及阳性转化子筛选与相应菌毛表达的检定等 ,初步表明该新型菌毛 (F1987)的基因定位于质粒上  相似文献   

H5N1亚型禽流感病毒核蛋白基因的克隆及分子进化分析     

王振国  金宁一  马鸣潇  金扩世  张洪勇  尹革芬  葛淑敏 《中国预防兽医学报》2004,26(6):436-438

用RT-PCR法,以1株h5N1亚型禽流感病毒RNA为模板,扩增了NP全基因cDNA.将cDNA克隆于pMD18-T载体,并对其进行测序.测序结果表明所克隆的1542个核苷酸的片段包含了核蛋白完整阅读框架,其中编码区为1497个核苷酸,编码498个氨基酸.将其序列与6株A型流感病毒NP基因序列进行比较,各毒株之间NP基因核苷酸序列同源性为92.5%～95.9%,编码的氨基酸同源性为97.0%～98.4%.本研究通过分子进化分析揭示了各毒株间的亲源关系.  相似文献   

Material in the middle ear of dogs having magnetic resonance imaging for investigation of neurologic signs     

M. C. Owen  BVSC    C. R. Lamb  MA  VETMB    D. Lu  BVET. MED.  MVM    M. P. Targett  BA  VETMB  PHD 《Veterinary radiology & ultrasound》2004,45(2):149-155

The aim of this study was to determine the prevalence and potential significance of finding material in the middle ear of dogs having magnetic resonance (MR) imaging. Of 466 MR studies reviewed, an increased signal was identified in the tympanic bulla in 32 (7%) dogs. Cavalier King Charles spaniels, Cocker spaniels, Bulldogs, and Boxers were over-represented compared to the population of dogs having MR imaging. Five (16%) dogs had definite otitis media and one (3%) had a meningioma invading the middle ear. Of the remaining dogs, 13 (41%) had possible otitis media and 13 (41%) had neurologic conditions apparently unrelated to otitis media. The most common appearance of material in the middle ear was isointense in T1-weighted images and hyperintense in T2-weighted images. There was no apparent correlation between the signal characteristics of the material and the diagnosis. Enhanced signal after gadolinium administration was observed affecting the lining of the bulla in dogs with otitis media and in dogs with unrelated neurologic conditions. In dogs without clinical signs of otitis media, finding an increased signal in the middle ear during MR imaging may reflect subclinical otitis media or fluid accumulation unrelated to inflammation. Brachycephalic dogs may be predisposed to this condition.  相似文献