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塔里木河干流中游灌区退耕封育的规模为 9× 10 3 hm2 ,其中 ,库灌区退耕 1.4 2× 10 3 hm2 ,河灌区退耕 3.5 7× 10 3 hm2 ,泵灌区退耕 4 .0 1× 10 3 hm2 。退耕封育后 ,农田灌溉用水改为生态灌溉用水 ,用水量减少。人工种植的农作物被天然野生植被所替代 ,同时可提高对保留耕地的利用率 ,扩大耕地的播种面积 ,增加地表植被的覆盖度。退耕封育后 ,可节约水量 0 .97× 10 8m3 ,除满足封育生态用水外 ,还可增加塔里木河下泄水量 0 .31× 10 8m3 。 相似文献
64.
AIM: To explore interaction and biological behaviour changes of two kinds of cells-blastocysts and hepatocarcinoma cells in the same microenvironment. METHODS:The models of mouse blastocysts co-cultured with human hepatocarcinoma cell lines were established, then biological behaviours and mutual effects of the two kinds of cells in co-culture system were observed. RESULTS: Compared with control group, hepatocarcinoma cells with differently invasive and metastatic potential significantly enhanced the rates of blastocyst hatchment , attachment and outgrowth(P<0.05). There was no significant difference in those among hepatocarcinoma cells co-cultured groups (P>0.05). The blastocyst hatched and attached to hepatocarcinoma cells with differently invasive and metastatic potential. Then, differential trophoblasts invaded hepatocarcinoma cells. The clear-cut interfaces were gradually formed between both sides. Hepatocarcinoma cells on interface showed changes of growth direction and cell shapes and did not invade blastocysts. CONCLUSIONS: Hepatocarcinoma cells promoted blastocyst development. Blastocysts implanted and invaded hepatocarcinoma cells with differently invasive and metastatic potential in vitro, which indicate that blastocyst implantation in vitro does not relate with the kinds and differential level of interactional cells and the low selectivity maybe relate with high adaptability of early life. 相似文献
65.
AIM: To investigate the role of nitric oxide synthase (NOS), soluble guanylyl cyclase (sGC) and protein kinase C (PKC) signaling in tumor necrosis factor-α (TNF-α)-induced cardioprotection against hypoxia/reoxygenation (H/R) injury. METHODS: Neonatal rat ventricular myocytes were pretreated with TNF-α or sodium nitroprusside (SNP) or L-arginine (L-Arg), respectively, for 12 h and then subjected to continuous hypoxia for 12 h, followed by reoxygenation for 6 h. The manganese superoxide dismutase (Mn-SOD) activity of the cells was measured after H/R. Myocyte injury was determined by the release of lactic dehydrogenase (LDH). RESULTS: TNF-α (105 U/L) significantly increased the Mn-SOD activity and decreased release of LDH from ventricular myocytes. The cardioprotection against H/R injury was induced by the pretreatment with SNP (5 μmol/L) or L-Arg (5 mmol/L), which was blocked by ODQ (10 μmol/L), the specific sGC inhibitor, and Chel (5 μmol/L), the specific PKC inhibitor. Pretreatment with L-NAME (100 μmol/L), ODQ, Chel, antoxidant 2-MPG (400 μmol/L) or tyrosine kinase inhibitor genistein (50 μmol/L) attenuated the increased Mn-SOD activity and reduced LDH level induced by TNF-α. CONCLUSION: The results suggest that NO may play a role in TNF-α-induced cardioprotection, which is mediated by sGC and PKC. 相似文献
66.
BsC3-41杀蚊幼制剂对蚊幼虫毒杀效果研究 总被引:2,自引:0,他引:2
通过以BsC3- 41杀蚊幼制剂对 3种蚊幼虫进行生物活性测定和野外灭蚊试验 ,结果表明 :该制剂对致乏库蚊CulexfatigansWiedemann的毒杀效果最好、对中华按蚊AnophelessinensisWiedemann次之、对白纹伊蚊AedesalbopictusSkuse的效果较差 ,2 4小时LC50值分别为 0 2 0 2 5 μg/ml、 2 5 363μg/ml和 5 9 730 2 μg/ml。野外水体灭蚊使用 3ml/m2 的浓度防治淡色库蚊效果可达 98 88%~ 1 0 0 0 0 % ,使用 1 0ml/m2 的浓度防治中华按蚊效果可达96 81 %~ 1 0 0 0 0 % ,使用 2 0 0ml/m2 的浓度防治白纹伊蚊效果达到 90 64%以上。 相似文献
67.
WANG Li-wei CHEN Li-xin MAO Jian-wen ZHU Lin-yan NIE Si-huai ZHONG Ping SUN Xue-rong CAI Bo LI Pan 《园艺学报》2004,20(8):1349-1352
AIM: To investigate the relationship between osmolarity, cell volume and cell proliferation in nasopharyngeal carcinoma cells. METHODS: MTT method was applied to detect the proliferation ability of the poorly-differentiated nasopharyngeal carcinoma cell (CNE-2Z) under various osmolarity conditions. The flow cytometry was used to analyse cell cycle distribution. Cell volume was obtained by the image analysis of living cells and cell viability was determined by the trypan blue assay. RESULTS: Cultivation of cells under the hypertonic conditions of 370 and 440 mOsmol/L increased cell volume by 8.7% and 27.8% and facilitated cell proliferation by 22.2% and 33.9%, respectively. However, hypotonic incubation of cells with osmolarity of 160 and 230 mOsmol/L decreased cell volume by 12.8% and 4.1% and inhibited cell proliferation by 34.0% and 15.6%, respectively. Cell volume was positively correlated with cell proliferation rate. Long-term cultivation of cells under anisotonic conditions did not significantly alter cell cycle distribution, but hypotonic cultivation decreased cell viability. CONCLUSION: Proliferation of nasopharyngeal carcinoma cells was closely correlated with the osmolarity of culture medium and cell volume. Hypotonic cultivation may inhibit cell proliferation by decreasing cell volume to facilitate cell death mechanisms. 相似文献
68.
AIM: To investigate the effects of β-mercaptoethanol (β-ME) and all-trans rentinal acid (RA) on glial fibrillary acidic protein (GFAP) expression in mesenchymal cells derived from mouse fetal liver in vitro. METHODS: Cells suspension from 14.5-days-old mouse fetal liver were cultured in DMEM/HEPES/F12 supplemented with 20% FCS and mesenchymal cells were acquired after discarding nonadherent cells. The 5th passage cells were induced by β-ME and RA. The characteristics of treated cells were assayed by immunocytochemistry staining at 5 hours and 5 days after induction. β-actin as an internal control, GFAP gene expression of mesenchyal cells was detected with semi-quantitative RT-PCR. RESULTS: After being inducted by β-ME and RA, 80% approximately of the cells exhibited typical neural morphology and about 85% expressed GFAP phenotype. Semi-quantitative RT-PCR showed that mRNA expression of GFAP increased in treated cells versus untreated cells (P<0.01). CONCLUSION: GFAP expression in mesenchymal cells derived from mouse fetal liver in vitro increases after being treated with β-ME and RA. 相似文献
69.
脂蛋白LPPQ是丝状霉形体丝状亚种SC型(MmmSC)非洲株、欧洲株和疫苗株所特有的。LPPQ N末端域具有良好的免疫原性,在牛体内可诱导产生强大、特异、早期、持续的免疫反应。本研究根据已发表的LPPQ基因序列设计引物,用Pyrobest^TM高保真DNA聚合酶从MmmSC HVRI X株中扩增出了LPPQ N末端基因序列,并进行了克隆与序列测定。核苷酸序列比较结果显示,HVRI X株的LPPQ N末端基因序列与国外发表的序列同源性为99.7%,由其推导的氨基酸序列同源性为99,1%,为脂蛋白LPPQ N末端基因体外表达奠定了基础。 相似文献
70.
仔猪小肠肌间神经丛NDP阳性神经元形态的定量研究 总被引:3,自引:2,他引:3
采用小肠铺片NADPH黄递酶组化染色和细胞影像分析的方法对0、5、28日龄的仔猪小肠肌间神经丛神经元群体的形态参数进行定量测定。结果表明:随日龄增长,小肠肌间神经元胞体面积增大,出生后的头几天尤为明显。NDP阳性肌间神经元胞核面积平均值与胞体面积平均值呈正相关。胞体面积平均值在0日龄为234.98±23.48μm2,5日龄为346.30±33.07μm2,28日龄为364.17μm2;胞核面积平均值在0日龄为69.85±6.27μm2,5日龄为88.25±2.39μm2,28日龄为84.15μm2。核质比随日龄呈下降趋势,核质比在0日龄为0.298±0.003,5日龄为0.257±0.027,28日龄为0.231。上述测量值不仅表现出日龄差异,而且在同一日龄小肠的前后段亦有所不同。NDP阳性神经元胞体和胞核大小都以十二指肠最大,空肠前段次之,回肠最小。0日龄仔猪神经元胞体面积分布在100~300μm2之间的占70.79%,5日龄和28日龄胞体面积分布在100~400μm2之间的分别占64.81%和63.22%。肌间神经丛NDP阳性神经元主要为Dogiel 型神经元。 相似文献