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Risk Factors for Lung Cancer in Non-smokers in Xuanwei County of china

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Biomedical and Environmental sciences 1993年第2期6卷 112-118页

作者： LAN QING, CHEN WEI, CHEN HONG, AND HE XING-ZHOUinstitute of Environmental Health and Engineering, chinese {2. of Preventive Medicine 2. Nan Wei Road, beijing 100050, china institute of Environmental Health and Engineering Chinese Academy of Preventive Medicine Beijing

Tobacco smoking and some types of occupational exposures have consistently been considered as important etiologic factors of lung cancer in industrial countries. At the First World Conference of Lung Cancer (Wyndwer, 1983), it was stressed that more attention should be paid to finding out the causes of lung cancer in non-smokers.In Xuanwei County, Yunnan Province, annual lung cancer death rate was 2..7 per 100,000 in males, among china's highest, and 2..3 per 100,000 in females, the china's highest. The female's lung cancer death rate in Xuanwei County was even much higher than that of the same period in USA white women (ECACM, 1979; Mulvihill, 1976). Marked district variation in cancer mortality exists within Xuanwei County. The county can be divided into high-, medium- and low-mortality areas. Over 90% of the population arc farmers. The local residents traditionally burned three major kinds of fuels: 'smoky' coal, 'smokeless' coal and 'wood', for heating and cooking. The three lung cancer high mortality areas, including 'Chengguan', 'Rongcheng' and 'Laibin' communes, mainly burned the 'smoky' coal from Laibin smoky-coal mine. The fuel was burned in a shallow, unventilated fire pit in the floor of the dwelling. Fuel burning in shallow unventilated pits has resulted in high indoor air pollution levels. The concentrations of airborne particles (pm 10) inside houses during smoky coal and wood combustion were very high. Indoor concentration of suspended particulates and dichloromethane extractable organics were 2..4mg/m3 and 17.6mg/m3 in burning of 'smoky' coal; 2..3mg/m3, 12.3mg/m3 for burning wood; and 1.8mg/m3, ***/m-1 for burning of smokeless coals. Levels of individual polycyclic aromatic hydrocarbons, including benzo(a)pyrene, were generally highest during burning of smoky coal, intermediate in burning wood, and least in smokeless coal. Women did most household chores, which include starting fire and cooking. Less than 0.2. of females smoked tobacco.

关键词： lung Risk Factors for Lung Cancer in Non-smokers in Xuanwei County of china

Reconstruction of paleo-redox conditions and early sulfur cycling during deposition of the Cryogenian Datangpo Formation in South china

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Reconstruction of paleo-redox conditions and early sulfur cy...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Lian-Jun Feng~(a,*),Xue-Lei Chu~(a,b),Jing Huang~(a,b),Qi-Rui Zhang~a,Hua-Jin Chang~(a,b) a institute of Geology and geophysics,{2. academy of sciences,beijing 10002.,china b Key Laboratory for Mineral Resources,{2. academy of sciences,beijing 10002.,china

In South china,the Datangpo black shales(663Ma-654.5 Ma) were deposited during the Cryognian interglacial time between the Sturtian and Marinoan ***-geochemical proxies,including different iron speciation and relevant ratios(Fe/Fe,Fe/Fe and Fe/Al ratios) and molybdenum concentrations,were used to reconstruct the paleo-depositional environment of this black shale *** ratios of different iron species(Fe/Fe>0.38 and Fe/Fe0.38 and Fe/ Fe≈0.80) and oxic(Fe/Fe<0.38) intervals could have ***,Fe/Al ratios(Fe/ Al≤0.51) confirm that water column may not be persistent euxinia during the deposition of the Datangpo black ***,molybdenum concentrations show a decreasing trend towards the top of the black shales,reconciling the gradual oxygenating trend during this period as stated *** toδS values in the Mesoproterozoic deep ocean,more positiveδS values of this study may result from a small size of sulfate *** small-size sulfate reservoir and concurrent enrichment of molybdenum indicate that the ocean chemistry in the Cryogenian Period is similar to that in the Archean Eon.

关键词： Redox conditions Cryogenian Iron species Molybdenum Sulfur isotope

Snow anomaly events from historical documents in eastern china during the past two millennia and implication for low-frequency variability of AO/NAO and PDO

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Snow anomaly events from historical documents in eastern Chi...

中国科学院地质与地球物理研究所2.08学术年会

作者： Guoqiang Chu,Qing Sun,Xiaohua Wang,and Junying Sun 1 institute of Geology and geophysics,{2. academy of sciences, beijing,china. 2.National Research Center of Geoanalysis,beijing,china. 3 Centre for Atmosphere Watch and Services,CMA,beijing,china.

[1]Models and instrumental data indicate that the spatial and temporal variations of snow cover are significantly related to atmospheric circulation(*** AO/NAO).Here, we present historical snow anomaly events during the past two millennia that provide a unique temporal window to studying long-term AO/NAO,a prominent phenomenon in *** descriptions such as "no snow during the winter" and "pray God for snow" are interpreted as convincing evidence for snow *** variations of positive/negative snow abnormal events show clear decadal to century variations during the past two *** on the previous instrumental research and comparison with other reconstruction data,we suggest the Index of Abnormal Snow(IAS) may be an AO-like atmospheric *** winter during the Medieval Warm Period (MWP)(AD 900-1300) might be strongly influenced by a predominantly positive AO with less snow condition, whereas the Little Ice Age(LIA)(AD 1300-1900) by negative AO concomitant with heavier snowfalls in East *** data show that a warm climate period(the MWP)/a cold period(the LIA) can be perturbed by a cold spell/a warm spell which are linked with a change in atmospheric ***-frequency variability of snow records may be intrinsic to the natural climate *** the dynamic mechanisms linking snow anomalies with atmospheric circulation(the AO/NAO,the PDO) is unclear on the decadal to century time scales,Pacific Ocean may play an important role in regulating atmospheric circulations since the IAS is highly correlated with the reconstruction of PDO.

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DISSOLUTION EQUILIBRIUM OF Mg VAPOUR IN LIQUID Fe

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Acta Metallurgica Sinica(English Letters) 1991年第9期4卷 230-233页

作者： ZHANG Xiaodong HAN Qiyong University of Science and Technology beijing,beijing,{2.CHEN Dong Hebei institute of Metallurgy,Shijiazhuang,{2. Univ of Science and Technology Beijing Beijing China

The dissolution equilibrium of magnesium vapour in liguid Fe has been studied in a two-tem- perature-zone furnace at 1600℃ by use of the vapour pressure *** equilibrium con- stant for the reaction Mg_(g)=[Mg] and the... 详细信息

关键词： liquid Fe Mg dissolution equilibrium

Weak Periodic Solutions of Non-Newtonian Viscous Incompressible Fluids

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 56-60页

作者： Boling GUO* and Guoguang LTN** (institute of Applied Physics and Computational Mathematics, Be1Jing 100088, china) and Guoguang LTN (Graduate School of china academy of Engineering Physics, beijing 100088, china) + (Department of Mathematics, Yunnan Univ Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Graduate School China Academy of Engineering Physics Beijing 100088 China Department of Mathematics Yunnan University Kunming 650091 China

The existence of weak periodic solution in time of non-Newtonian fluids with a time periodic forcing is established.

关键词： periodic solution weak periodic solution bipolar fluid

ALLOYING BEHAVIOUR OF Ca IN STEEL 58CrV

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Acta Metallurgica Sinica(English Letters) 1992年第6期5卷 449-453页

作者： LU Feng CAO Fengyu LI Chengji University of Science and Technology beijing,beijing,{2.ZHANG Yongxiang CHEN Yonggang beijing institute of Machine Tools,beijing,{2. Faculty of Metallograph,University of Science and technology beijing,beijing 100083,{2. beijing Univ of Science and Technology Beijing China

Effect of Ca on hardenability and CCT diagram of steel 58CrV has been investigated by means of end-quenching and thermal *** addition of 0.006 wt-%Ca to the steel may improve the hardenability,reduce the critical cooling rate of transformation of pearlite or bainite under continuous cooling and increase the M_*** analysis showed that Ca segre- gates markedly along austenitie grain boundaries,and accelecrates the segregation of C,Cr and *** is believed that besides towards deoxidizing and desulphurizing as well as improving sulphide morphology,a trace of Ca in steel 58CrV behaves towards microalloying.

关键词： Ca steel 58CrV microalloying hardenability CCT diagram

Homologous chromosome synapsis and recombination in rice

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Homologous chromosome synapsis and recombination in rice

第十一届全国植物基因组学大会

作者： Zhukuan Cheng,Mo Wang,Yi Shen,Kejian Wang State Key Laboratory of Plant Genomics,institute of Genetics and Developmental Biology,chinese {2. of sciences,beijing 100101,china

During meiosis,correct segregation of homologous chromosomes at the first division of meiosis requires that they associate into bivalents,where each chromosome is connected to its homologue by discrete physical points...

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Microstructure Characteristic of In-situ Ti/TiC Composites

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Journal of Materials Science & Technology 2001年第1期17卷 103-104页

作者： Bo YANG beijing institute of Aeronauticul Materials, beijing 100095, china Erlin ZHANG Yunxue JIN Zhaojun ZHU and Songyan ZENG National Key Lab. of Precision Hot Processing of Metals, Harbin institute of Technology, Harbin 150001, china Inst. of Aeronaut. Mater. Beijing 100095 China

TiC reinforced titanium composites has been produced with different Al content and C content by XDTM. The results have shown that TiC particles are of two different morphologies f coarse dendritical primary TiC and short bar-shape eutectic TiC. Al content has great effects on the morphology of TiC. With the increasing of Al content, the morphology of primary TiC changes from coarse developed dendrite into short bar-shape or plate--shape TiC with 35%Al. Meanwhile, the structure of the matrix changes from single Ti to Ti and Ti3Al, and to Ti3Al and TiAl. However, the C content has no influence on the microstructure of matrix. When the C content is less than 1.2., the dendrite TiC disappears and only short bar-shape or plate-shape TiC exists in the composites. In addition, the effect of he3t treatment on the morphology of TiC has also Studied.

关键词： TiC Microstructure Characteristic of In-situ Ti/TiC Composites

Comparative study in the spontaneous response of the medial geniculate body and inferior colliculus in rats with thalamic reticular nucleus lesion after contralateral cochlear ablation

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Comparative study in the spontaneous response of the medial ...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Dan-Yi LU,Shi-Gang HE,Ju-Fang HE 1 CAS-Hong Kong Joint Research Laboratory for Visuo-Auditory Integration,institute of Biophysics,chinese {2. of sciences,beijing 100101,china 2.State Key Laboratory of Brain and Cognitive sciences,institute of Biophysics,chinese {2. of sciences,15 Datun Road,beijing 100101,china 3 Laboratory of Applied Neuroscience,Department of Rehabilitation sciences,The Hong Kong Polytechnic University, Hung Horn,Kowloon,Hong Kong,china

＜正＞Tinnitus is a ringing,swishing,or other type of noise that originated in the ear or *** hypothesize that damage of the cochlear hair cells causes hypersensitivity of the cells after a period of reorganization in the auditory pathway.A malfunctioning of the thalamic reticular nucleus（TRN）would decrease its inhibition to the auditory transmission and eventually causes *** the present study,we would investigate the neuronal property change in the medial geniculate body（MGB）and inferior colliculus（IC）of the rats after cochlear ablation and TRN lesion at different *** acid was injected into the TRN to lesion the *** contralateral cochlea to the recording hemisphere was ablated under an operating *** responses of the MGB and IC were recorded with the implanted extracellular electrodes while the rat was in different physiological *** found that neurons in the auditory thalamus should more changes than those in the *** results would lead us to a further investigation on the potential mechanism focusing on the changes in the MGB.

关键词： Tinnitus cochlea thalamic reticular nucleus(TRN) medial geniculate body(MGB) inferior colliculus(IC)