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“黄发”岂同“垂髫”
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作者 张意馨 《初中生之友(快乐号)(上)》 2010年第4期37-37,共1页
有人写了一篇《母亲的姿势》,系回忆童年往事的散文。作者写道:“我突然记起黄发垂髫初懂事理时.有一回和母亲走亲戚。”在这个句子里.“初懂事理”无疑指孩童时期.那么“黄发垂髫”作何解呢?
关键词 中学 语文教学 词语 词汇 “黄发”
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Elicitation on Artemisinin Biosynthesis in Artemisia annua Hairy Roots by the Oligosaccharide Extract from the Endophytic Colletotrichum sp. B501 被引量:12
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作者 王剑文 夏仲豪 谭仁祥 《Acta Botanica Sinica》 CSCD 2002年第10期1233-1238,共6页
The oligosaccharide elicitor from the mycelial wall of an endophytic Colletotrichum sp. B501 promoted the production of artemisinin in Artemisia annua L. hairy root culture. When hairy roots of 22-day-old cultures (la... The oligosaccharide elicitor from the mycelial wall of an endophytic Colletotrichum sp. B501 promoted the production of artemisinin in Artemisia annua L. hairy root culture. When hairy roots of 22-day-old cultures (later growth phase) were exposed to the elicitor (20 mg/L) for 4 d, the maximum content of artemisinin reached 1.15 mg/g, a 64.29% increment over the control. The electron X-ray microanalysis disclosed the rapid accumulation of Ca 2+ in the elicited cortical cells of hairy root. The electronic microscope observation revealed the high electron density area in vacuole of elicited cells. During the first day of elicitation the peroxidase activity of hairy roots was improved sharply. Some cellular morphological changes including cell shrinkage, condensation of cytoplasm and nuclear fragmentation, coincident with the appearance of DNA ladders, were observed after the third day of elicitation. It was suggested that the oligosaccharide elicitor triggered the programmed cell death, which may provide the substance or chemical signal for artemisinin biosynthesis. 展开更多
关键词 Artemisia annua Colletotrichum sp. B501 a fungal endophyte oligosaccharide elicitor ARTEMISININ eliciting response
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Landslide disaster in the loess area of China 被引量:16
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作者 周金星 朱春云 +2 位作者 郑景明 王晓慧 刘洲鸿 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期157-161,165,共5页
China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and bec... China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and becomes major factors hindering the social and economic development of loess regions. Through different indexes, the authors divided the landslides into 9 principal types and analyzed the distribution characteristics of loess landslide in time and space, the affecting factors and mechanism of landslides. It is pointed out that time and spatial distributions of landslides are closely correlative to topographic and geomorphic conditions, earthquake and rainfall, and the key influencing factors include topography, geomorphology, new tectonic movements, earthquake activity, surface water, ground water and human activities. The authors emphasized that the natural condition of loess areas was favorable to landslides, human activities impelled its occurrence and that controlling the loess landslide was an urgent task for sustainable development in the loess zone. 展开更多
关键词 Loess landslide Landslide mechanism Natural disasters
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Advance in Rice Bacterial Leaf Streak Researches 被引量:4
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作者 张荣胜 陈志谊 刘永锋 《Agricultural Science & Technology》 CAS 2015年第2期298-305,310,共9页
Rice bacterial leaf streak,caused by Xanthomonas oryzae pv.oryzicola,is an important bacterial disease in rice-planting areas in South China and Southeast Asian countries.It occurs every year in local areas.This paper... Rice bacterial leaf streak,caused by Xanthomonas oryzae pv.oryzicola,is an important bacterial disease in rice-planting areas in South China and Southeast Asian countries.It occurs every year in local areas.This paper reviews the research advance in the occurrence and harms of rice bacterial leaf streak in China,classification of Xanthomonas oryzae and infection characteristics,pathogenic factors and pathogenicity of rice bacterial leaf streak and breeding of bacterial leaf streakresistance rice cultivars.Some issues involved in occurrence and control of rice bacterial leaf streak were presented,and the areas on which the future studies might be focused were discussed. 展开更多
关键词 Rice bacterial leaf steak Xanthomonas oryzae Occurrence and harm Control
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Structural and Optical Performance of GaN Thick Film Grown by HVPE
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作者 魏同波 马平 +5 位作者 段瑞飞 王军喜 李晋闽 刘喆 林郭强 曾一平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第1期19-23,共5页
Thick GaN films were grown on GaN/sapphire template in a vertical HVPE reactor. Various material characterization techniques,including AFM, SEM, XRD, RBS/Channeling, CL, PL, and XPS, were used to characterize these Ga... Thick GaN films were grown on GaN/sapphire template in a vertical HVPE reactor. Various material characterization techniques,including AFM, SEM, XRD, RBS/Channeling, CL, PL, and XPS, were used to characterize these GaN epitaxial films. It was found that stepped/terraced structures appeared on the film surface,which were indicative of a nearly step-flow mode of growth for the HVPE GaN despite the high growth rate. A few hexagonal pits appeared on the surface, which have strong light emission. After being etched in molten KOH, the wavy steps disappeared and hexagonal pits with {1010} facets appeared on the surface. An EPD of only 8 ×10^6cm^-2 shows that the GaN film has few dislocations. Both XRD and RBS channeling indicate the high quality of the GaN thick films. Sharp band-edge emission with a full width at half maximum(FWHM)of 67meV was observed, while the yellow and infrared emissions were also found. These emissions are likely caused by native defects and C and O impurities. 展开更多
关键词 GAN HVPE CL RBS/channeling yellow emission infrared emission
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Induction of Gynogenesis of Silurus astus Using Cold Shock 被引量:1
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作者 程果 李学军 +2 位作者 乔志刚 石灵 彭新亮 《Agricultural Science & Technology》 CAS 2008年第2期122-125,共4页
[ Objective] The cold shock method was used to induce diploid gynogenesis of Silurus astus. [ Mthod ] The Silurus astus sperms were irradiated by ultraviolet, then conducted for fertilization. The different cold shock... [ Objective] The cold shock method was used to induce diploid gynogenesis of Silurus astus. [ Mthod ] The Silurus astus sperms were irradiated by ultraviolet, then conducted for fertilization. The different cold shock starting time and duration were set to observe diploid gynogenesis of Silurus astus. [ Result] Under such inducing condition that ultraviolet irradiated 15 min,cold shock started 5 rain after fertilization, and cold shock duartion was 40 rain,the survival rate of diploid Silurus astus reached the highest(8.5% ). [ Conclusion] The experiment laid foundation for culturing new excellent Silurus astus variety and accumulated original files tor further study of gynogenesis development mechanism. 展开更多
关键词 Silurus asotus GYNOGENESIS DIPLOID Cold shock
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Discussion on Development of Hainan Huanghuali(Dalbergia odorifera T.Chen)
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作者 黄浩伦 李芳书 黄慧德 《Agricultural Science & Technology》 CAS 2015年第11期2539-2542,共4页
On the morphological characteristics, growth environment and quality, rarity, and wood characteristics and value of Huanghuali, this paper discusses the development ways of Hainan Huanghuali It is suggested that Halna... On the morphological characteristics, growth environment and quality, rarity, and wood characteristics and value of Huanghuali, this paper discusses the development ways of Hainan Huanghuali It is suggested that Halnan Huanghuali could be well grown by guiding farmers to make full use of wasteland, slopes, scattered land, roadside and other resources; the landscaping greenbelt of the courtyard area and the residential area could be planned with nature as a main consideration for planting Huanghuali; and landscaping-type Huanghuali planting could make full use of local environment and surrounding local resources, highlighting the personalized landscaping greenbelt, forming good transition between residential area and urban space and creating a natural kindly living environment for the residents, so as to play the best ecological, social and economic benefits. 展开更多
关键词 Huanghuali (Dalbergia odorifera T.Chen) DEVELOPMENT DISCUSSION HAINAN
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Chemical Compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens 被引量:30
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作者 周劲松 熊辉岩 +2 位作者 杨春江 焦迎春 盛海彦 《Agricultural Science & Technology》 CAS 2008年第2期90-92,共3页
The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic p... The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil. 展开更多
关键词 Armillaria luteo-rirens Volatile oil Chemical compositions GC-MS
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Effect of Fulvic Acid on Growth and Yield Components of Direct Seeding Rice 被引量:3
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作者 王晓琳 苏云 +1 位作者 许晓明 李贵 《Agricultural Science & Technology》 CAS 2013年第7期966-972,共7页
ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice (Nanjing 44). MethodThe rice seeds were soaked in 0 (water as a control), 1, 2, 4 and 6 ... ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice (Nanjing 44). MethodThe rice seeds were soaked in 0 (water as a control), 1, 2, 4 and 6 g/L fulvic acid (FA) before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II (PSII) (Fv/Fm), excitation energy capture efficiency of opened PSII reaction center (Fv’/Fm’) and efficiency of the open reaction centre (ΦPS II) increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration (4-6 g/L) significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage. 展开更多
关键词 Fulvic acid Direct seeding rice Growth and development Yield components
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Effects of Liquid Seaweed Bio-organic Fertilizer on Seed Germination and Seedling Growth of Vegetables 被引量:1
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作者 刘培京 王飞 张树清 《Agricultural Science & Technology》 CAS 2014年第3期407-411,共5页
[Objective] This study aimed to investigate the effects of liquid seaweed bio-organic fertilizer on seed germination and seedling growth of different vegetables. [Method] Serial dilution concentrations of liquid seawe... [Objective] This study aimed to investigate the effects of liquid seaweed bio-organic fertilizer on seed germination and seedling growth of different vegetables. [Method] Serial dilution concentrations of liquid seaweed bio-organic fertilizer were prepared for seed soaking and pot incubation of cucumber, tomato and chili, to ob- serve the effects of liquid seaweed bio-organic fertilizer on seed germination and seedling growth of vegetables. [Result] Compared with the control, germination rate of cucumber and tomato seeds applied with 600-fold liquid seaweed bio-organic fer- tilizer varied significantly; germination rate of chili seeds applied with 400-fold liquid seaweed bio-organic fertilizer varied significantly; germination energy and germination index of chili seeds applied with different dilution concentrations of liquid seaweed bio-organic fertilizer presented no significant differences. In addition, 200-fold and 400-fold liquid seaweed bio-organic fertilizer significantly improved the root length, plant height, plant fresh weight, plant dry weight, chlorophyll content and leaf area of cucumber, tomato and chili seedlings; after treated with 600-fold liquid seaweed bio-organic fertilizer, root length, chlorophyll content and leaf area of cucumber seedlings varied significantly compared with the control, but no significant differences were observed in plant height, plant fresh weight and plant dry weight; after treated with 600-fold liquid seaweed bio-organic fertilizer, root length, chlorophyll content, plant height, plant fresh weight and plant dry weight of chili and tomato varied sig- nificantly compared with the control, but no significant differences were observed in leaf area. [Conclusion] Soaking vegetable seeds with liquid seaweed bio-organic fer- tilizer can significantly improve seed generation rate and seedling growth. 展开更多
关键词 Liquid seaweed bio-organic fertilizer CUCUMBER Chili Tomato Seed germination Seedling growth
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Model of gas exchange dynamics for modified-atmosphere packages containing fresh produce
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作者 刘颖 李云飞 +1 位作者 王如竹 田平海 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期314-318,共5页
A model for modified-atmosphere packaging (MAP) systems containing fruits and vegetables was developed.The computer simulation was performed to predict the gas mass concentrations inside the packages and was success... A model for modified-atmosphere packaging (MAP) systems containing fruits and vegetables was developed.The computer simulation was performed to predict the gas mass concentrations inside the packages and was successfully verified by experiments with yellow peaches at 5,15 and 25 ℃ using two types of packaging films.A Michaelis-Menten type respiration model with noncompetitive inhibition mechanism due to CO2 was adopted while the respiration rates were measured with an improved permeable system method suitable for either steady or unsteady state.The applicability of the model in the design of MAP systems was demonstrated with a calculation to evaluate film specification and equilibrium concentrations of O2 and CO2 in the package containing yellow peaches. 展开更多
关键词 gas exchange dynamics modified-atmosphere package respiration rate yellow peach
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Ontogeny and Metamorphic Patterns of Female Reproductive Organs of Ephedra sinica Stapf (Ephedraceae) 被引量:2
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作者 杨永 《Acta Botanica Sinica》 CSCD 2001年第10期1011-1017,共7页
Ontogeny and metamorphic. development of female reproductive organs in Ephedra sinica Stapf were surveyed. At the end of April, female cones began to initialize from the vegetative buds. Pollination occurred in mid-Ma... Ontogeny and metamorphic. development of female reproductive organs in Ephedra sinica Stapf were surveyed. At the end of April, female cones began to initialize from the vegetative buds. Pollination occurred in mid-May and seeds matured at the beginning of July. The ontogenetic pattern of female reproductive organs of E. sin ca is basically similar to that of E. distachya L. The foliar nature of the outer envelope of the ovule in Ephedra is corroborated. Reduction of ovule number as a tendency of speciation in the genus is substantiated by the occurrence of tri-ovulate cones coupled with comprehensive characters of the genus. The metamorphic patterns as well as the leaf nature of the outer envelope indicate that female cones of Ephedra are compound while the female reproductive units of the ovulate cone have been reduced from secondary reproductive shoots similar to those of cordaites by phylogenetic transformation, fusion and reduction. Each fertile bract together with its axillary female reproductive unit composed the Bract Scale and Seed Scale Complex of Ephedra. 展开更多
关键词 EPHEDRA female reproductive unit ONTOGENY metamorphic development bract scale and seed scale complex
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Analysis of Data on Xanthan Fermentation in Stationary Phase Using Black Box and Metabolic Network Models 被引量:2
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作者 马红武 赵学明 唐寅杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第4期321-325,共5页
The xanthan fermentation data in the stationary phase was analyzed using the black box and the metabolic network models. The data consistency is checked through the elemental balance in the black box model. In the met... The xanthan fermentation data in the stationary phase was analyzed using the black box and the metabolic network models. The data consistency is checked through the elemental balance in the black box model. In the metabolic network model, the metabolic flux distribution in the cell is calculated using the metabolic flux analysis method, then the maintenance coefficients is calculated. 展开更多
关键词 xanthan fermentation black box model metabolic flux analysis maintenance coefficients
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Macrobenthic community structure and species composition in the Yellow Sea and East China Sea in jellyfi sh bloom 被引量:8
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作者 彭松耀 李新正 +1 位作者 王洪法 张宝琳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期576-594,共19页
To understand the characteristics of macrobenthic structures and the relationship between environment and benthic assemblages in jellyfish bloom, we studied the macrobenthos and related environmental factors in the co... To understand the characteristics of macrobenthic structures and the relationship between environment and benthic assemblages in jellyfish bloom, we studied the macrobenthos and related environmental factors in the coastal waters of the Yellow Sea and East China Sea. Data were collected during two seasonal cruises in April and August of 2011, and analyzed with multivariate statistical methods. Up to 306 macrobenthic species were registered from the research areas, including 115 species of Polychaeta, 78 of Crustacea, 61 of Mollusca, 30 of Echinodermata, and 22 of other groups. Nine polychaete species occurred at frequencies higher than 25% from the sampling stations: Lumbrineris longifolia, Notomastus latericeus, Nin6e palmata, Ophelina acuminata, Nephtys oligobranchia, Onuphis geophiliformis, Glycera chirori, Terebellides stroemii, and Aricidea fragilis. Both the average biomass and abundance of macrobenthos are higher in August (23.8 g/m^2 and 237.7 ind./m^2) than those in April (11.3 g/m^2 and 128 ind./m^2); the dissimilarity ofmacrobenthic structures among stations is as high as 70%. In terms of the dissimilarity values, we divided the stations into four clusters in spring and eight in summer. The ABC curve shows that the macrofauna communities in high jellyfish abundance were not changed. Canonical correspondence analysis showed that depth, temperature, median grain size, total organic carbon of sediment and total nitrogen in sediment were important factors affecting the macrozoobenthic community in the study area. 展开更多
关键词 MACROBENTHOS community structure Yellow Sea East China Sea jellyfish outbreak
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Responses of terrestrial water cycle components to afforestation within and around the Yellow River basin 被引量:3
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作者 LV Meixia MA Zhuguo PENG Shaoming 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第2期116-123,共8页
Reforestation has attracted worldwide attention because of its multiple environmental benefits,but its impact on water resources is complicated and still controversial. In this study, the authors conducted numerical e... Reforestation has attracted worldwide attention because of its multiple environmental benefits,but its impact on water resources is complicated and still controversial. In this study, the authors conducted numerical experiments within and around the Yellow River basin under the Grain-forGreen project using the Weather Research and Forecasting model. The results showed that the terrestrial water cycle process was sensitive to land use/cover change in the study region. Under the increase of mixed forests within and below the basin, the basin-averaged precipitation and evaporation increased by 223.17 and 223.88 mm respectively, but the surface runoff decreased by 2.22 mm from 2006 to 2010. In other words, the forest-induced increase in evaporation exceeded that of precipitation along with decreased surface runoff. Importantly, the afforestation effects on water resources seemed to enhance with time, and the effects of the same vegetation change were different in dry and wet years with different precipitation amounts(i.e. different atmospheric circulation background). It should be noted that it is difficult to obtain one product that can explicitly reflect the spatial distribution of actual land cover change promoted by the Grain-for-Green project in the Yellow River basin, which is an important obstacle to clearly identify the reforestation impacts. A land cover dataset derived from advantages of multiple sets of data therefore needs to be proposed. 展开更多
关键词 AFFORESTATION precipitation EVAPORATION RUNOFF Yellow River basin
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Sporo-pollen Assemblage and Paleoclimate Events in Shelf Area of the Southern Yellow Sea Since 15 ka B.P. 被引量:1
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作者 孟广兰 韩有松 +1 位作者 王少青 王珍岩 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第1期44-53,共10页
Based on the authors’1986 to 1994 sporo-pollen assemblage analysis in the southern Yellow Sea area, data from 3 main cores were studied in combination with 14C, palaeomagnetic and thermoluminescence data. The evoluti... Based on the authors’1986 to 1994 sporo-pollen assemblage analysis in the southern Yellow Sea area, data from 3 main cores were studied in combination with 14C, palaeomagnetic and thermoluminescence data. The evolution of the paleoclimate environments in the southern Yellow Sea since 15ka B.P. was revealed that, in deglaciation of the last glacial period, the climate of late glaciation transformed into that of postglaciation, accompanied by a series of violent climate fluctuations. These evolution events happened in a global climate background and related to the geographic changes in eastern China. We distinguished three short-term cooling events and two warming events. Among them, the sporo-pollen assemblage of subzone A 1 showed some cold climate features indicating that a cooling event occurred at about 15-14ka. B.P. in early deglaciation. This subzone corresponds to the Oldest Dryas. In subzone A 3, many drought-enduring herbal pollens and some few pollens of cold-resistant Picea, Abies, etc. were found, which indicated that a cooling event, with cold and arid climate, occurred at about 12-11ka. B.P. in late deglaciation. This subzone corresponds to the Younger Dryas. The sporo-pollen assemblage of zone B showed warm and arid climate features in postglaciation. Although the assemblage of subzone B 2 indicated a cold and arid climate environment, the development of flora in subzone B 2 climate was less cold than that in A 3. Subzone B 2 indicated a cooling event which occurred at about 9ka B.P. in early Holocene. Subzone A 2, with some distinct differences from subzone A 1 and A 3, indicated a warming event which occurred at 14-13ka. B.P. and should correspond to a warming fluctuation. The sporo-pollen assemblage of zone C showed features of warm-moist flora and climate, and indicated a warming event which universally occurred along the coast of eastern China at 8-3ka B.P. in middle Holocene, and its duration was longer than that of any climate events mentioned above. This period was climatic optimum and belonged to an altithermal period in postglaciation. 展开更多
关键词 southern Yellow Sea QUATERNARY sporo-pollen assemblage paleoclimate events environment evolution
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A Clinical Study on Haunglian Fire-Purging Mixture In Treatment of 46 Cases of Primary Hypertension 被引量:1
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作者 李运伦 段树民 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2005年第1期29-33, ,共5页
In order to observe the therapeutic effects of Huanglian Fire-Purging Mixture (黄连清降合剂) on primary hypertension, 46 cases of primary hypertension in the treatment group were treated with Huanglian Fire-Purging Mi... In order to observe the therapeutic effects of Huanglian Fire-Purging Mixture (黄连清降合剂) on primary hypertension, 46 cases of primary hypertension in the treatment group were treated with Huanglian Fire-Purging Mixture to clear away heat from the liver, relieve mental stress, purge fire and remove toxin;and the other 26 cases of primary hypertension in the control group were treated with Niuhuang Bolus for Lowering Blood Pressure (牛黄降压丸). The effect in the treatment group was obviously superior to that in the control group (P<0.05). The Huanglian Fire-Purging Mixture shows noticeable effects 3-6 hours after medication. The mixture can improve the clinical symptoms, the left ventricular diastolic function and myocardial ischemia, correct dyslipoproteinemia and dysglycemia, and reduce blood viscosity. And it is safe and with no obvious adverse reactions. 展开更多
关键词 PHYTOTHERAPY ADULT Aged Drugs Chinese Herbal FEMALE Humans HYPERTENSION Male Middle Aged Single-Blind Method Treatment Outcome
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Trends in Annual and Seasonal Pan Evaporation in the Lower Yellow River Basin from 1961 to 2010 被引量:7
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作者 JI Xing-Jie WANG Ji-Jun +2 位作者 GU Wan-Long ZHU Ye-Yu LI Feng-Xiu 《Advances in Climate Change Research》 SCIE 2012年第4期195-204,共10页
The annual and seasonal trends in pan evaporation in the lower Yellow River Basin based on quality-controlled data from 10 meteorological stations in 1961-2010 are analyzed. The causes for the changes in annual and se... The annual and seasonal trends in pan evaporation in the lower Yellow River Basin based on quality-controlled data from 10 meteorological stations in 1961-2010 are analyzed. The causes for the changes in annual and seasonal pan evaporation are also discussed. The results suggest that, despite the 1.15~C increasing in annual mean surface air temperature over the past 50 years (0.23°C per decade), the annual pan evaporation has steadily declined by an average rate of-7.65 mm per year. By comparison, this change is greater than those previously reported in China. Significant decreasing trends in annual pan evaporation have been observed at almost all stations. As a whole, seasonal pan evaporation decreased significantly, especially in summer, whereas seasonal temperature increased significantly, except in summer. Thus, the pan evaporation paradox exists in the lower Yellow River Basin. The trend analysis of other meteorological factors indicates significant decrease in sunshine duration and wind speed, but no significant variations in precipitation and relative humidity at annual and seasonal time scales. By examining the relationship between precipitation and pan evaporation, it did not show a concurrent decrease in pan evaporation and increase in precipitation. The partial correlation analysis discovered that the primary cause of decrease in annual and seasonal pan evaporation is the decrease in wind speed. A further examination using a stepwise regression shows that decrease in wind speed and sunshine duration, and increase in mean temperature axe likely to be the main meteorological factors affecting the annual and seasonal pan evaporation in the lower Yellow River Basin over the past 50 years. 展开更多
关键词 lower Yellow River Basin pan evaporation TREND meteorological factors
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Occurrence and Effects of Pineapple Mealybug Wilt Disease in Central Uganda
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作者 Bosco Bua Jeninah Karungi Geoffrey Kawube 《Journal of Agricultural Science and Technology(A)》 2013年第5期410-416,共7页
Pineapple mealybug wilt disease (PMWD) is one of the latest outbreaks of diseases attacking pineapple in Uganda. However, its occurrence and effects have not been documented and quantified, yet the disease poses a s... Pineapple mealybug wilt disease (PMWD) is one of the latest outbreaks of diseases attacking pineapple in Uganda. However, its occurrence and effects have not been documented and quantified, yet the disease poses a serious threat to the pineapple industry. Therefore, the objective of this study was to assess the occurrence and effects of PMWD on pineapple in central Uganda. Semi-structured questionnaire was used to solicit information from 82 respondents consisting of farmers, opinion leaders, key informants, political and technical leadership during May 2011. PMWD was observed in all the fields surveyed but with varying incidences and severities. In addition, PMWD was more common during the dry seasons than the rainy seasons where higher incidences were associated with high mealybug populations. PMWD manifested as a syndrome characterized by yellowing of leaves, stunting, wilting and rotting of roots. The effects of PMWD were variable but yield reductions and low plant populations were widely reported. Although, the occurrence of PMWD was reported to the different level of authority in the districts, very little was done to curb its spread. 展开更多
关键词 Control EFFECTS PERCEPTIONS pineapple mealybug wilt disease occurrence.
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A rare case of obstructive jaundice secondary to pancreatic plasmacytoma
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作者 Binesh F Akhavan A Navabii H 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第5期297-299,共3页
Pancreatic plasmacytoma is a rare entity & present with features of mass lesion of pancreas.We presented an interesting case of pancreatic plasmacytoma with severe abdominal pain and cholestatic symptoms.This case... Pancreatic plasmacytoma is a rare entity & present with features of mass lesion of pancreas.We presented an interesting case of pancreatic plasmacytoma with severe abdominal pain and cholestatic symptoms.This case highlights the importance of considering pancreatic plasmacytoma in differential diagnosis of patients with cholestatic jaundice & abdominal pain and that not all pancreatic head mass are adenocarcinoma,so biopsy is advisable. 展开更多
关键词 PLASMACYTOMA PANCREAS cholestatic jaundice
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