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1.
Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.  相似文献   
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Ginsenoside compound K (CK), a rare ginsenoside originating from Panax Ginseng, has been found to possess unique pharmacological activities specifically as anti-cancers. However, the role of cytochrome P450s (CYPs) in the metabolism of CK is unclear. In this study, we screened the CYPs for the metabolism of CK in vitro using human liver microsomes (HLMs) or human recombinant CYPs. The results showed that CK inhibited the enzyme activities of CYP2C9 and CYP3A4 in the HLMs. The Km and Vmax values of CK were 84.20±21.92 μM and 0.28±0.04 nmol/mg protein/min, respectively, for the HLMs; 34.63±10.48 μM and 0.45±0.05 nmol/nmol P450/min, respectively, for CYP2C9; and 27.03±5.04 μM and 0.68±0.04 nmol/nmol P450/min, respectively, for CYP3A4. The IC50 values were 16.00 μM and 9.83 μM, and Ki values were 14.92 μM and 11.42μM for CYP2C9 and CYP3A4, respectively. Other human CYP isoforms, including CYP1A2, CYP2A6, CYP2D6, CYP2E1, and CYP2C19, showed minimal or no effect on CK metabolism. The results suggested that CK was a substrate and also inhibitors for both CYP2C9 and CYP3A4. Patients using CK in combination with therapeutic drugs that are substrates of CYP2C9 and CYP3A4 for different reasons should be careful, although the inhibiting potency of CK is much poorer than that of enzyme-specific inhibitors.  相似文献   
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为研究青藏高原草地承载力的空间演变特征并对其进行预警,以已有的青藏高原净初级生产力数据为基础,核算了该地区的草地理论载畜量及演变趋势,并结合县域实际存栏量,划定了草地承载力的预警等级。结果表明:(1)青藏高原草地承载力整体呈东高西低的格局,其中高寒草原和高寒草甸是该地区草地承载力的主要组成部分;(2)2000-2015年,青藏高原理论载畜量由8614.89万羊单位增至9451.53万羊单位;(3)青藏高原整体处于超载状态,2000-2010年超载状况加剧,至2015年超载状况稍有缓解,草畜平衡指数由67.88%增至79.90%,再降至67.91%。目前亟需优先控制72个红色预警县(超载状态正在加剧)的牲畜存栏量,避免超载状况进一步恶化。未来需要通过控制牲畜存栏量、调整畜牧区发展布局和提高草地生产力等多项措施的结合来改善青藏高原地区的草地承载状况,维持草地生态系统的可持续发展。  相似文献   
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A potent platelet aggregation inducer (platelet aggregoserpentin) was purified from Trimeresurus gramineus snake venom by DEAE-Sephadex A-50 and Sephacryl S-300 column chromatography. It was homogeneous as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It elicited dose-dependently platelet aggregation and serotonin release reaction in rabbit platelet-rich plasma and platelet suspension. Exogenous calcium was required for its activity. Creatine phosphate/creatine phosphokinase and apyrase showed no significant inhibitory effect on aggregoserpentin-induced platelet aggregation in platelet suspension. Aggregoserpentin induced aggregation in ADP-refractory platelet-rich plasma. It caused no detectable malonic dialdehyde formation in the process of platelet aggregation. Indomethacin did not inhibit aggregoserpentin-induced platelet aggregation. Mepacrine abolished preferentially its aggregating activity, while prostaglandin E1 completely blocked both aggregoserpentin-induced aggregation and release reaction. Furthermore, platelet aggregoserpentin lowered basal and prostaglandin E1-stimulated cAMP levels in platelet suspension. Nitroprusside inhibited both its aggregating and releasing activity, while verapamil preferentially blocked its aggregating activity. It is concluded that aggregoserpentin activated platelets through lowering cAMP levels or the activation of endogenous phospholipase A2, resulting in the formation of platelet activating factor, but not of prostaglandins.  相似文献   
8.
本试验是用番木瓜环斑病毒(Papaya ringspot virus, PRV)提纯制剂免疫的BALB/c小白鼠脾细胞与Sp~2/o-Ag14骨髓瘤细胞融合,获得三个能稳定传代并分泌抗番木瓜环斑病毒的单克隆抗体的杂交瘤细胞系。其中23H1 McAb的效价较高,用ELISA检测,腹水抗体效价高达1:76800,能被PRV兔抗血清所阻断。这3个杂交瘤细胞系产生的单抗与TMV和CMV无血清交叉反应。它们可把PRV四个毒株初步区分为三个血清型。  相似文献   
9.
Abstract The fatty acid (FA) compositions for total lipids from fat body, hemolymph and flight muscle of the armyworm moths, Mythirnna separata, at rest and after tethered flight for 1 h were determined by GC and GC-MS. The composition in these tissues comprises myristic acid (1%-2%), palmitic acid (more than 35%1, palmitoleic acid (9%-11%), stearic acid (less than 1%), oleic acid (about 32%), linoleic acid (12%-17%) and linolenic acid (3%-6%). After flight, FA level in the fat body, compared to that at rest, shows a significant decline at about 20 μg/mg tissue.h-1; the concentration of FAs in hemolymph rises evidently, but change of FA content in flight muscle appears to be small. From the changes of proportional composition of FAs in fat body, hemolymph and flight muscle, it is found that the FAs selectively utilized for flight in flight muscle are predominantly the palmitic acid and oleic acid.  相似文献   
10.
慢性缺氧对大鼠肺内皮素表达的影响   总被引:2,自引:0,他引:2  
本文以ABC法和原位杂交技术,观察了慢性缺氧时大鼠肺组织内内皮素-1(ET-1)的表达情况,结果发现:①正常肺血管内皮细胞有少许ET-1样阳性染色物质呈现。②缺氧IW后,肺内ET-1含量增加,主要位于肺血管内皮细胞和支气管粘膜上皮细胞。③缺氧2W和3W后,ET1阳性免疫物质进一步增加,于肺泡细胞内也见到阳性染色。④缺氧1W后肺内ET-1mRNA表达增加,缺氧2W和3W后,ET-1mRNA的表达进一步加强。提示缺氧可刺激肺内ET-1mRNA的表达,慢性缺氧时肺内ET-1持续分泌增加,这可能是缺氧性肺动脉高压发生的重要因素之一。  相似文献   
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