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Cenozoic Adakite-type Volcanic Rocks in Qiangtang,Tibet and Its Significance 被引量:11
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作者 LIUShen HURuizhong +5 位作者 FENGCaixia CHIXiaoguo LICai YANGRihong WANGTianwu JINWei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第2期187-193,共7页
Volcanic rocks in the study area, including dacite, trachyandesite and mugearite, belong to the intermediate-acid, high-K calc-alkaline series, and possess the characteristics of adakite. The geochemistry of the rocks... Volcanic rocks in the study area, including dacite, trachyandesite and mugearite, belong to the intermediate-acid, high-K calc-alkaline series, and possess the characteristics of adakite. The geochemistry of the rocks shows that the rocks are characterized by SiO2>59%, enrichment in A12O3(15.09-15.64%) and Na2O (>3.6%), high Sr (649-885 μg/g) and Sc, low Y contents (<17 μg/g), depletion in HREE (Yb<1.22 μg/g), (La/Yb)N>25, Sr/Y>40, MgO<3% (Mg<0.35), weak Eu anomaly (Eu/Eu=0.84-0.94), and lack of the high field strength elements (HFSE) (Nb, Ta, Ti, etc.). The Nd and Sr isotope data (87Sr/86Sr=0.7062-0.7079, 143Nd/144Nd=0.51166-0.51253, εNd= -18.61-0.02), show that the magma resulted from partial melting (10%-40%) of newly underplated basaltic lower crust under high pressure (1-4 GPa), and the petrogenesis is obviously affected by the crust's assimilation and fractional crystallization (AFC). This research will give an insight into the uplift mechanism of the Tibetan plateau. 展开更多
关键词 CENOZOIC lower crust high-K calc-alkaline volcanic rock UNDERPLATING partial melting uplift of plateau QIANGTANG TIBET
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Distribution of available soil water capacity in China 被引量:53
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Rice Yield and Water Use as Affected by Soil Management Practices 被引量:11
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作者 WANGXiao-Ying XIEHong-Tu +1 位作者 LIANGWen-Ju WENDa-Zhong 《Pedosphere》 SCIE CAS CSCD 2004年第3期331-337,共7页
A field experiment was conducted at the Shenyang Experimental Station of Ecology, Chinese Academy of Sciences,to study the effects of soil management practices on water use and rice (Oryza sativa L.) yield in an aquic... A field experiment was conducted at the Shenyang Experimental Station of Ecology, Chinese Academy of Sciences,to study the effects of soil management practices on water use and rice (Oryza sativa L.) yield in an aquic brown soil during 2001 and 2002. A completely random experimental design with three replications was employed, having four soil management practices as treatments, namely: an undisturbed plow layer (CK), a thin plastic film (TN), a thick plastic film (TI) and subsoil compacting (CP). Results indicated no significant differences arong all treatments for rice biomass and grain yields. Also, water consumption was about the same for treatments TN and CK, however the treatments TI and CP were much lower with more than 45% and 40% of the irrigation water in the treatments TI and CP, respectively,saved each year compared to CK. Therefore, water use efficiency was higher in the treatments TI and CP. These results will provide a scientific basis for the water-saving rice cultivation. 展开更多
关键词 土壤水分损失总量 浸透性 土壤管理 水利用率
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Studies on growth rate and grazing mortality rate by microzooplankton of size-fractionated phytoplankton in spring and summer in the Jiaozhou Bay,China 被引量:16
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作者 ZHANGLiyong SUNJun +1 位作者 LIUDongyan YUZishan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第2期85-101,共17页
Dilution experiments were performed to examine the growth rate and grazing mortality rate of size-fractionated phytoplankton at three typical stations, inside and outside the bay, in the spring and summer of 2003 in t... Dilution experiments were performed to examine the growth rate and grazing mortality rate of size-fractionated phytoplankton at three typical stations, inside and outside the bay, in the spring and summer of 2003 in the Jiaozhou Bay, China. In spring, the phytoplankton community structure was similar among the three stations, and was mainly composed of nanophytoplankton, such as, Skeletonema costatum and Cylindrotheca closterium. The structure became significantly different for the three stations in summer, when the dominant species at Stas A, B and C were Chaetoceros curvisetus, Pseudo-nitzschia delicatissima, C. affinis, C. debilis, Coscinodiscus oculus-iridis and Paralia sulcata respectively. Tintinnopsis beroidea and T. tsingtaoensis were the dominant species in spring, whereas the microzooplankton was apparently dominated by Strombidium sp. in summer. Pico- and nanophytoplankton had a relatively greater growth rate than microzooplankton both in spring and summer. The growth rate and grazing mortality rate were 0.18~0.44 and 0.12~1.47 d-1 for the total phytoplankton and 0.20~0.55 and 0.21~0.37 d-1 for nanophytoplankton in spring respectively. In summer, the growth rate and grazing mortality rate were 0.38~0.71 and 0.27~0.60 d-1 for the total phytoplankton and 0.11~1.18 and 0.41~0.72 d-1 for nano- and microphytoplankton respectively. The carbon flux consumed by microzooplankton per day was 7.68~39.81 mg/m3 in spring and 12.03~138.22 mg/m3 in summer respectively. Microzooplankton ingested 17.56%~92.19% of the phytoplankton standing stocks and 31.77%~467.88% of the potential primary productivity in spring; in contrast, they ingested 34.60%~83.04% of the phytoplankton standing stocks and 71.28%~98.80% of the potential primary productivity in summer. Pico- and nanophytoplankton appeared to have relatively greater rates of growth and grazing mortality than microphytoplankton during the experimental period. The grazing rate of microzooplankton in summer was a little bit greater than that in spring because of the relatively higher incubation temperature and different dominant microzooplankton species. Microzooplankton preferred ingesting nanophytoplankton to microphytoplankton in spring, while they preferred ingesting picophytoplankton to nanophytoplankton and microphytoplankton in summer. Compared with the results of dilution experiments performed in various waters worldwide, the results are in the middle range. 展开更多
关键词 MICROZOOPLANKTON PHYTOPLANKTON selective grazing carbon to chlorophyll-a ratio grazing pressure Jiaozhou Bay
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Phylogeny of the cuttlefishes (Mollusca: Cephalopoda) based on mitochondrial COI and 16S rRNA gene sequence data 被引量:11
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作者 LINXiangzhi ZHENGXiaodong +1 位作者 XIAOShu WANGRucai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期699-707,共9页
To clarify cuttlefish phylogeny, mitochondrial cytochrome c oxidase subunit I (COI) gene and partial 16S rRNA geneare sequenced for 13 cephalopod species. Phylogenetic trees are constructed, with the neighbor-joining ... To clarify cuttlefish phylogeny, mitochondrial cytochrome c oxidase subunit I (COI) gene and partial 16S rRNA geneare sequenced for 13 cephalopod species. Phylogenetic trees are constructed, with the neighbor-joining method.Coleoids are divided into two main lineages, Decabrachia and Octobrachia. The monophyly of the order Sepioidea,which includes the families Sepiidae, Sepiolidae and Idiosepiidae , is not supported. From the two families ofSepioidea examined, the Sepiolidae are polyphyletic and are excluded from the order. On the basis of 16S rRNA andamino acid of COI gene sequences data, the two genera (Sepiella and Sepia) from the Sepiidae can be distinguished, butdo not have a visible boundary using COI gene sequences. The reason is explained. This suggests that the 16S rDNAof cephalopods is a precious tool to analyze taxonomic relationships at the genus level, and COI gene is fitter at ahigher taxonomic level (i.e., family). 展开更多
关键词 PHYLOGENY CEPHALOPODS CUTTLEFISH COI 16S rRNA
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Effects of adjusting vertical resolution on the eastern equatorial Pacific cold tongue 被引量:10
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作者 WUFanghua LIUHailong +1 位作者 LIWei ZHANGXuehong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第3期16-27,共12页
The vertical resolution of LICOM1.0 (LASG/IAP Climate System Ocean Model, version 1.0) is adjusted by increasing the level amount within the upper 150 m while keeping the total of levels. It is found that the eastern ... The vertical resolution of LICOM1.0 (LASG/IAP Climate System Ocean Model, version 1.0) is adjusted by increasing the level amount within the upper 150 m while keeping the total of levels. It is found that the eastern equatorial Pacific cold tongue is sensitive to the adjustment. Compared with the simulation of the original level scheme, the adjusting yields a more realistic structure of cold tongue extending from the coast of Peru to the equator, as well as a temperature minimum at Costa Rica coast, north of the cold tongue. In the original scheme experiment, the sharp heating by net surface heat flux at the beginning of spin-up leads to a great warm- ing in the eastern equatorial Pacific Ocean. The weak vertical advection due to a too thick mixed layer in the coarse vertical structure also accounts for the warm bias. The fact that most significant improvements of the upper 50 m temperature appear at the region of the thinnest mixed layer indicates the necessity of fine vertical resolution for the eastern equatorial Pacific Ocean. However, the westward extension of equatorial cold tongue, a defect in the original scheme, gets even more serious in the adjusting scheme due to the intensi- fied vertical velocity and hence vertical advection in the central-eastern equatorial Pacific Ocean. 展开更多
关键词 ocean general circulation model vertical resolution eastern equatorial Pacific Ocean cold tongue
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Environmental Soil Phosphorus Testing and Phosphorus Release in Taihu Lake,China 被引量:7
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作者 HUANGQing-Hui WANGZi-Jian +2 位作者 WANGDong-Hong: MAMei JINXiang-Can 《Pedosphere》 SCIE CAS CSCD 2004年第4期461-466,共6页
A microtiter plate assay (MPA) for soluble reactive phosphorus (SRP) was applied to samples in overlying water and pore water as well as in three forms of environmental soil test phosphorus (P) types: water soluble ph... A microtiter plate assay (MPA) for soluble reactive phosphorus (SRP) was applied to samples in overlying water and pore water as well as in three forms of environmental soil test phosphorus (P) types: water soluble phosphorus (WSP),diluted calcium chloride extractable phosphorus (PCaCl2), and Olsen-P in the sediments of Taihu Lake, China, where potential P release in response to pH was analyzed. MPA for rapid P analysis was shown to be promising when applied on samples of natural water and sediment extracts. Concentrations of WSP and PCaCl2 in the sediments were much lower than those of Olsen-P. Olsen-P levels in the littoral sediments along the north coast of Meiliang Bay in Taihu Lake (80to 140 mg kg-1) were much higher than those in the mouth of the bay (less than 50 mg kg-1). The risk of P release in the mouth area of Meiliang Bay was lower than that in the north littoral zone with a risk of sediment P release induced by pH increases. 展开更多
关键词 生物利用率 湖泊富营养 水体污染
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Photodynamic inhibitory effects of three perylenequinones on human colorectal carcinoma cell line and primate embryonic stem cell line 被引量:14
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作者 LanMa HongTai +3 位作者 CongLi YuZhang Ze-HuaWang Wei-ZhiJi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第3期485-490,共6页
AIM: To investigate the photodynamic inhibitory effects of Elsinochrome A (EA), Hypocrellin A (HA) and Hypocrellin B (HB) on human colorectal carcinoma Hce-8693 cells and rhesus monkey embryonic stem R366.4 cells, via... AIM: To investigate the photodynamic inhibitory effects of Elsinochrome A (EA), Hypocrellin A (HA) and Hypocrellin B (HB) on human colorectal carcinoma Hce-8693 cells and rhesus monkey embryonic stem R366.4 cells, via inducing apoptosis.METHODS: EA, HA and HB were extracted from metabolites of Hypomyces (Fr) Tul.Sp. R366.4 cells or Hce8693 cells were cultured with different concentrations of EA, HA or HB respectively, irradiated and incubated with fresh medium for 2 h. Cell cycle analysis was performed by flow cytometry (FCM). Data were expressed as means ±SD and analysis of variance and Student' t-test for individual comparisons.RESULTS: The photodynamic bioactivity of EA was first reported in this study. After irradiation for 5 min, 6 min, 10 min or 20 min, photoactivated EA at lower concentrations,which were 10-7 Mol/L, 10-6 Mol/L, 10-5 Mol/L respectively,had no cytotoxic effects on R366.4 ES ceils. Whereas, all of the three perylenequinones could induce apoptosis with a dose-dependent manner when Hce-8693 cells were incubated with photoactivated EA, HA and HB respectively. When Hce-8693 cells were incubated with EA at 10-6 Mol/L and irradiated 5 lin, 6 min, 10 min and 20 min respectively,the rates of EA-induced apoptosis were 0, 0, 13.4 % and 40.5 %. While the rates of HA-induced apoptosis were 29.5 %, 32.0 %, 40.2 % and 22.6 %. And the rates of HBinduced apoptosis were 0, 0, 0 and 13.7 % respectively.Meanwhile, after 10-5 Mol/L treatment, the rates of EA-induced apoptosis were 32.7 %, 19.3 %, 26.4 % and 52.7 %, the rates of HA-induced apoptosis were 47.2 %, 39.1%, 45.2% and 56.6 %, and the rates of HB-induced apoptosis were 0, 0, 20.0 % and 13.9 % respectively.CONCLUSION: EA, HA and HB have significant anti-cancer activity. The order of photodynamic inhibitory effects on tumor cells would be approximately HA>EA>HB. The molecular mechanisms of apoptosis may not be induced by reactive oxygen species and are worth further investigation. 展开更多
关键词 结直肠癌 光力学抑制作用 胚胎干细胞 细胞培养 细胞凋亡
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Cryopreservation of cynomolgus monkey (Macacafascicularis)spermatozoa in a chemically defined extender 被引量:11
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作者 Ya-HuiLi Ke-JunCai +5 位作者 LeiSu MoGuan Xie-ChaoHe HongWang AndrasKovacs Wei-ZhiJi 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第2期139-144,共6页
Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. T... Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant.The effects of glycerol concentration (1%,3 %,5 %,10 % and 15 % [v/v]) and its equilibration time (10 min,30 min,60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity.Results:The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P<0.05) for 5 % glycerol (42.95±2.55 and 50.39±2.42,respectively) than those of the other groups (1%:19.19±3.22 and 24.84±3.64;3 %:34.23±3.43 and 41.37±3.42;10 %: 15.68±2.36 and 21.39±3.14;15 %:7.47±1.44 and 12.90±2.18).The parameters for 30 min equilibration (42.95±2.55 and 50.39±2.42) were better (P<0.05) than those of the other groups (10 min:31.33±3.06 and 38. 98±3.31;60 min:32.49±3.86 and 40.01±4.18;90 min:31.16±3.66 and 38.30±3.78).Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity.Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender,which is related to the concentration and the equilibration time of glycerol. 展开更多
关键词 CRYOPRESERVATION MACACAFASCICULARIS chemically defined extender GLYCEROL
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Vertical distribution of plant nematodes in an aquic brown soil under different land uses 被引量:9
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作者 MENGFan-xiang LiangWen-ju +3 位作者 OUWei JIANGYong LIQi WENDa-zhong 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期39-42,i003,共5页
The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland i... The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland in the Shenyang Experimental Station of Ecology, Chi- nese Academy of Sciences in November of 2003. The results showed that the numbers of some dominant genera under different land uses decreased with the increase of soil depth. Helicotylenchus was most dominant genus under each land use type. Genera of Filenchus, Psilen- chus and Tylenchus in paddy field occurred at the depth of 0–20 cm; while Paratylenchus in fallow field and woodland, as well as Praty- lenchus in maize field presented in the deeper soil layers (0–80 cm). Significant correlations between the numbers of dominant genera of plant nematodes and soil chemical properties were found in this study. The number of Helicotylenchus under different land uses was posi- tively correlated with C/N ratio, total C, total N, total P, alkai-N, and Olsen-P. The numbers of Filenchus and Paratylenchus in paddy field, Pratylenchus in maize field and Paratylenchus in fallow field were negatively correlated with soil pH, and positively correlated with total C, total N and alkai-N. This study results showed that it is essential to sample at a certain depth according to the vertical distribution informa- tion of different genera of plant nematodes in adequately assessing the population size of plant nematodes. 展开更多
关键词 Vertical distribution Plant nematodes Dominant genera Aquic brown soil Land use
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Studies on the regional feature of organic carbon in sediments off the Huanghe River Estuary waters 被引量:8
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作者 YUANHuamao LIUZhigang +4 位作者 SONGJinming LüXiaoxia LIXuegang LINing ZHANTianrong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第1期129-134,共6页
Organic carbon (OC) in definitely small area sediments(according to marine dimension)off the Huanghe River Estuary is investigated in order to evaluate the feature of regional difference of physical and chemical prope... Organic carbon (OC) in definitely small area sediments(according to marine dimension)off the Huanghe River Estuary is investigated in order to evaluate the feature of regional difference of physical and chemical properties in marginal sea sediments.The distributions of OC in sediments with natural grain size and the relationship with the pH,Eh ,Es and Fe3+/Fe2+ are discussed.In addition,OC decomposition rates in surfacial/subsurfacial sediments are estimated.OC concentrations range from 0.26% to 1.8%(wt)in the study area. Significant differences in OC content and in horizontal distribution as well as various trends in surfacial /subsurfacial sediments exhibit the feature of regional difference remarkably in marginal sea sediments. The complicated distribution of OC in surface sediments is due to the influence of bacterial activity and abundance, bioturbation of benthos and physical disturbance. The OC decomposition rate constant in surfacial /subsurfacial sediments ranges from 0.009 7 to 0.076 a-1 and the relatively high values may be mainly related to bacteria that are mainly responsible for OC mineralization;meio-and macrofauna affect OC degradation both directly, through feeding on it, and indirectly through bioturbation and at the same time coarse sediments are also disadvantageous to OC preservation.In almost all the middle and bottom sediments the contents of OC decrease with the increase of deposition depth, which indicates that mineralization of OC in the middle and bottom sediments has occurred via processes like SO reduction and Fe-oxide reduction. 展开更多
关键词 regional feature organic carbon SEDIMENTS Huanghe River Estuary
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Comparison of two approaches for detecting the depth of edge influence on vegetation diversity in the arid valley of southwestern China 被引量:7
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作者 LILi-guang HEXing-yuan LIXiu-zhen WENQing-chun ZHAOYong-hua 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期105-108,共4页
Three types of landscape boundary (forest/pepper field, forest/cabbage field,and forest/grassland) were selected in the arid valley of upper reaches of Minjiang River,southwestern China. On the basis of vegetation div... Three types of landscape boundary (forest/pepper field, forest/cabbage field,and forest/grassland) were selected in the arid valley of upper reaches of Minjiang River,southwestern China. On the basis of vegetation diversity, the depth of edge influence (DEI) ondifferent types of landscape boundaries was estimated using principal components analysis (PCA)method and moving split-window techniques (MSWT). The results showed that in the 5 transects, PCAmethod was able to detect the edge influence depth with 3 transects, while MSWT could explain 4transects. It is concluded that PCA and MSWT both can be used to detect the depth of edge influencewithin 50 m from the edge to the interior. Similar conclusions were drawn in the forest of eachtransect with the two methods, but no similar conclusions were drawn in the pepper field of eachtransect. Although the two methods have advantages and disadvantages respectively, they are usefultools for characterizing edge dynamics. Comparing the two methods, MSWT is more successful. 展开更多
关键词 boundary moving split-window techniques (MSWT) principal componentsanalysis (PCA) depth of edge influence (DEI)
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Landscape pattern change in the upper valley of Min River 被引量:8
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作者 ZHAOYong-hua HEXing-yuan +1 位作者 HUYuan-man CHANGYu 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期31-34,i002,共5页
The upper valley of Min River (102° 59′ –104° 14′ E, 31° 26′ – 33° 16′ N), which is consisted of the counties Wenchuan, Maoxian, Lixian, Heishui, and Songpan, refers to the part up to Dujiang... The upper valley of Min River (102° 59′ –104° 14′ E, 31° 26′ – 33° 16′ N), which is consisted of the counties Wenchuan, Maoxian, Lixian, Heishui, and Songpan, refers to the part up to Dujiangyan City, and locates on the transition zone from the Tibetan Plateau to the Si- chuan Basin. It is one of the most important forest areas in China, especially in Sichuan Province. Over past two decades, the landscape changed remarkably in the region. The 3S techniques (Remote Sensing (RS), Geographic Information System (GIS) and Global Position System (GPS)) were used to classify the images and analyze the landscape change. The remotely sensed data of Landsat TM 1986 and Landsat ETM+ 2000 were used to analyze the landscape change of the region. The landscape were classified into 10 types of cropland, for- est, shrub land, economic forest, grassland, build up land, river, lake, swamp, and unused land. The results showed that: 1) the woodland and grassland were dominating landscape types in the upper valley of Min River, which is more than 91% of the study area; 2) the alteration of the landscape was mainly happened among forest, shrub land, grassland, economic forest, cropland, and build up land, where forest de- creased from 51.17% to 47.56%; 3) the landscape fragmentation in the upper valley of Min River was aggravated from 1986 to 2000. 展开更多
关键词 Landscape change Min River Sichuan Province China
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Enhancement of humoral immune responses to HBsAg by heat shock protein gp96 and its N-terminal fragment in mice 被引量:6
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作者 Hong-TaoLi Jia-BinYan +4 位作者 JingLi Ming-HaiZhou Xiao-DongZhu Yu-XiaZhang PoTien 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第19期2858-2863,共6页
AIM: Most studies on the immune effect of gp96 were focused on its enhancement of CTLs. It is interesting to know whether gp96 could influence the humoral immune response, and whether the recombinant N-terminal fragme... AIM: Most studies on the immune effect of gp96 were focused on its enhancement of CTLs. It is interesting to know whether gp96 could influence the humoral immune response, and whether the recombinant N-terminal fragment of gp96 could substitute native gp96 to stimulate the immune system.METHODS: gp96 isolated from livers of normal mice and its N-terminal fragment (amino acid 22-355) expressed in E coli were used for immunization of BALb/c mice. Eight groups of mice received one of the following regiments subcutaneously in 100 μL phosphate buffered saline (PBS)at an interval of 3 wk. Group 1: PBS only; group 2:gp96 only; group 3: N-terminal fragment only; group 4: HBsAg only; group 5: HBsAg+gp96; group 6: HBsAg+N-terminalfragment; group 7: HBsAg+incomplete Freud's adjuvant; group 8: HBsAg+N-terminal fragment (95 ℃ heated for 30 min). Serum anti-HBsAg antibody levels were assayed by ELISA. CTL responses in splenocytes were analyzed by ELISPOT after the last vaccination.RESULTS: The average titer of serum anti-HBsAg antibodyin the mice immunized with HBsAg together with gp96 or its N-terminal fragment were much higher than those immunized with HBsAg alone detected by ELISA. The cellular immune response of the mice immunized with HBsAg together with gp96 or its N-terminal fragment was not different with those immunized with HBsAg alone measured by ELISPOT assay.CONCLUSION: gp96 or its N-terminal fragment greatly improved humoral immune response induced by HBsAg, but failed to enhance the CTL response, which demonstrated the potential of using gp96 or its N-terminal fragment as a possible adjuvant to augment humoral immune response against HBV infection. 展开更多
关键词 体液免疫 HBSAG 热休克蛋白GP96 乙型肝炎病毒
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A New Halogenated Biindole and A New Apo-carotenone from Green Alga Chaetomorpha basiretorsa Setchell 被引量:6
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作者 DaYongSHI LiJunHAN +5 位作者 JieSUN ShuaiLI SuJuanWANG YongChunYANG XiaoFAN JianGongSHI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第6期777-780,共4页
关键词 Green alga Chaetomorpha basiretorsa Sethcell 4 4′-dichloro-5 5′-dibromo-7 7′-di- methoxy-2 2′-bi-1H-indole 1′S* 4′R*-8-(4′-hydroxy-2′ 6′ 6′-trimethylcyclohex-2-enyl)-6-methyl- oct-3E 5E 7E-trien-2-one.
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Optimization of solid fermentation of cellulase from Trichoderma koningii 被引量:3
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作者 LIPei-jun JINGDe-bing +1 位作者 ZHOUQi-xing ZHANGChun-gui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期816-820,共5页
To exploit peashrub resources in Ordos as fodders, it is very crucial to realize industrial production of cheap cellulase of high activity by optimizing culture technology, especially culture substrate. In this study,... To exploit peashrub resources in Ordos as fodders, it is very crucial to realize industrial production of cheap cellulase of high activity by optimizing culture technology, especially culture substrate. In this study, a new prescription experiment based on uniform design ideal was invented and successfully applied in the solid fermentation of Trichoderma koningii F244, which was performed with two different temperature degrees. The activities of FPA, cotton lyase, CMCase and β-glucosidase were assayed and then mathematical models of enzymatic activities, which were figured out by Unconstraint Mathematical Programming, were developed by Multivariate Regression Program of SPSS10.0. Enzymatic activities of optimized substrate prescriptions corresponding to mathematical models were forecasted to determine an ideal substrate prescription. It is revealed that in solid fermentation, Tween80 has negative effect on cellulase production. Furthermore, the ideal prescription for cellulase complex production by Trichoderma koningii F244 was straw powder 16.9%,wheat bran 26.5%, (NH 4) 2SO 4 9.5% and water 47.1%, whose corresponding cellulase activity was expected to be at the same high level with that of Trichoderma reesei Q9414 on its own recommended substrate. Especially, goats mainly fed on peashrub tissues mixed with cellulase complex of this prescription and culture technology, got an incremental ratio of 0.3 kg/d, which brought a very promising feeding prospect for local peashrub resource. By populization of this cellulase complex, it can integrate living standard, economic construction of local residents into vegetational restoration tightly and thus this paper will be very meaningful to be use for reference for western China like Ordos to realize its sustainable development of economy, society and environment. 展开更多
关键词 Trichoderma koningii substrate prescription FPA CMCASE cotton lyase Β-GLUCOSIDASE
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Preliminary studies on differential defense responses induced during plant communication 被引量:4
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作者 JinYingPENG ZhongHaiLI +4 位作者 HuiXIANG JianHuaHUANG ShiHaiJIA XueXiaMIAO YongPingHUANG 《Cell Research》 SCIE CAS CSCD 2005年第3期187-192,共6页
We compared the expression patterns of three representative genes in undamaged tomato and tobacco plants in response to exposure to either tomato or tobacco fed on by Helicoverpa armigera (cotton bollworm). When tomat... We compared the expression patterns of three representative genes in undamaged tomato and tobacco plants in response to exposure to either tomato or tobacco fed on by Helicoverpa armigera (cotton bollworm). When tomato and tobacco, two species of one family, were incubated in the chambers with the tomato plants damaged by the cotton bollworm, the expression of the PR1, BGL2, and PAL genes was up-regulated in leaves of both plants. However, the levels of gene expression were significantly higher in the tomato than that in the tobacco. In addition, the activities of enzymes, peroxidase, polyphenol oxidase, and lipoxygenase were found to be higher in the tomato than those in the tobacco. Similar results were obtained when the damaged plants were replaced by the tobacco. 展开更多
关键词 植物间信息交流 烟草 西红柿 棉铃虫 诱导防御物质
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On the Fossil Pediastrum from the Gaoximage Section, Hunshandak Sandy Land and Its Ecological Significance Since 5 000 a BP 被引量:7
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作者 XUZhao-Liang LIChun-Yu KONGZhao-Chen 《Acta Botanica Sinica》 CSCD 2004年第10期1141-1148,共8页
The fossil Pediastrum was investigated from the Gaoximage section ( 42°57′14″ N, 115°22′3″E, Air 1 253 m ) in the Hunshandak Sandy Land, Inner Mongolia (Nei Mongol) of China in order to gain a better und... The fossil Pediastrum was investigated from the Gaoximage section ( 42°57′14″ N, 115°22′3″E, Air 1 253 m ) in the Hunshandak Sandy Land, Inner Mongolia (Nei Mongol) of China in order to gain a better understanding the changes of palaeovegetation, palaeoenvironment and palaeoclimite since 5000 aBP when the pollen-spore was studied. The results show that the fossil Pediastrum assemblage can be divided into three periods: Ⅰ. 5 000-3 500 a BP, the fossil Pediastrum occurred rarely. Based on this result it can be surmised that the lake might be fresh water with poor organics. Ⅱ. 3 500-1 500 a BP, the fossil Pediastrum likes volcanic emerged. It probably indicate moist conditions and the grasslands were developed during this time; and Ⅲ. 1 500-200 a BP, the fossil Pediastrum disappeared. It can show that the lake water become salty and shrunk, and the weather could become drier and drier. This result shows that Pediastrurn, a kind of facies fossil, happened simultaneously in the pollen-spore assemblage during the second period. Sometimes Pediastrurncan reach more than 60 per cent of the total spore pollen assemblage, indicating that Gaoximage lake was not only fresh water with abundant eutrophic materials but also occupied a large area during 3 500-1 500 a BP. 展开更多
关键词 化石 盘星藻属 砂地 荒漠化 生态学 中国 内蒙古 古植被
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Characterization of Function of Three Domains in Dishevelled-1: DEP Domain is Responsible for Membrane Translocation of Dishevelled-1 被引量:5
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作者 WeiJunPAN ShuZhaoPANG +3 位作者 TaoHUANG HuiYunGUO DianqingWU LinLI 《Cell Research》 SCIE CAS CSCD 2004年第4期324-330,共7页
Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl... Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl) protein was considered as the intersection of Wnt signal traffic. In this study, we characterized the function of three domains (DIX,PDZ and DEP) of Dvl-1 in canonical Wnt signal transduction and Dvl-1 membrane translocation. It was found both DIX and DEP domain were sufficient to block Wnt-3a-induced LEF-1 transcriptional activity and free cytosol β-catenin accumulation; whereas PDZ domain and a functional mutant form of DEP domain (DEP-KM) had no effect on canonical Wnt signaling. In addition, when cotransfected with Fz-7, DEP domain, but not DIX, PDZ or DEP-KM, translocated and co-localized with Fz-7 to the plasma membrane, which was similar to Dvl-1. Furthermore, it was DEP domain that could block Fz-7-induced membrane translocation of Dvl- 1 via a possible competitive mechanism. These results strongly suggest that DEP domain is responsible for the membrane translocation of Dvl-1 protein upon Wnt signal stimulation. 展开更多
关键词 信号转导 膜易位 WNT 基因 蛋白质
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Catalytic Performance of Zeolite NU-87 with 10- and 12-Member Rings for Methane Dehydroaromatization 被引量:3
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作者 CHENHuiying LIULin +3 位作者 XULongya SHENWenjie XUYide BAOXinhe 《催化学报》 SCIE CAS CSCD 北大核心 2004年第11期845-846,共2页
关键词 沸石NU-87 甲烷 芳构化 沸石MCM-22
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