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Crystallization and preliminary X-ray analysis of SNR 141--An N-terminal fragment of staphylococcal nuclease R

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Chinese Science Bulletin 1997年第11期42卷 957-959页

作者： Ye, S Wan, ZL Zhou, B Jing, GZ Liang, dc CHINESE ACAD SCI INST BIOPHYSSTATE KEY LAB BIOMACROMOLBEIJING 100101PEOPLES R CHINA

STAPHYLOCOCCAL nuclease(SNase A,EC 3.***.4.7),which hydrolyzes the phosphodiesterbond of DNA and RNA,and releases 3’-phosphate mononucleotides and dinucleotides,con-sists of 149 amino acid residues(MW=16 807)without sulfhydryl and disulfide *** A was originally derived from Staphylococcus *** the gene of the enzyme wascloned and inserted into several expression *** crystal structure was detected

关键词： crystallization staphylococcal nuclease R N-terminal fragment.

Preliminary crystallographic investigation of allophycocyanin from Porphyra yezoensis in cubic crystal form

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Chinese Science Bulletin 1997年第18期42卷 1578-1580页

作者： Liu, JY Zhang, JP Wan, ZL Liang, dc Zhang, JP Wu, HJ CHINESE ACAD SCI INST BIOPHYSSTATE KEY LAB BIOMACROMOLBEIJING 100101PEOPLES R CHINA

THE phycobilisomes in blue-green algae and red algae are the functional units which absorb and transfer light energy. These supramolecular aggregates are attached on the outer surface of the thylakoid or photosynthetic membrane. Phycobilisomes absorb light in the range of 450—650 nm with an overall quantum efficiency of almost 100%, Electron microscopic studies showed that phycobilisomes consist of two distinct structure parts: the core and the rods.

关键词： phycobiliprotein allophycocyanin crystal growth crystallographic analysis red algae.

PREPARATION　AND　PROPERTIES　OF　RARE　EARTH　HYDROXIDES　AND　OXIDES　ULTRAFINE　POWDERS　IN　ALCOHOL

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Chinese Chemical Letters 1995年第11期6卷 1017-1020页

作者： Dong, XT Liu, ZR Yang, KS Liu, JH Hong, GY Yu, dc Changchun Inst Opt & Fine Mech Dept Mat Engn Changchun 130022 Peoples R China Acad Sinica Changchun Inst Appl Chem Changchun 130022 Peoples R China

A series of rare earth hydroxides and oxides ultrafine powders have been prepared by precipitation method using alcohol as dispersive and proteclive reagent. It was first to find that the crystallite size of cubic rare earth oxides had lanthanide shrinking effect, but average crystal lattice distortion rate possessed lanthanide swelling effect; the change of diffraction intensity with atomic number presented an inverted W type, and double peaks structure was formed.

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Oral polymorphonuclear neutrophil characteristics in relation to oral health： a cross-sectional, observational clinical study

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International Journal of Oral Science 2016年第3期8卷 191-198页

作者： Patrick Rijkschroeff Ineke dc Jansen Fridus A van der Weijden Bart IF Keijser Bruno G Loos Elena A Nicu Department of Periodontology Academic Centre for Dentistry Amsterdam Amsterdam The Netherlands Department of Preventive Dentistry Academic Centre for Dentistry Amsterdam Amsterdam The Netherlands Microbiology and Systems Biology TNO Earth Environmental and Life Sciences Zeist The Netherlands Top Institute Food and Nutrition Wageningen The Netherlands

Polymorphonuclear neutmphils （PMNs） have a major role in the innate immune system. However, little is known about PMN contribution in relation to oral health. The objective of this study was to investigate the numbers and functional characteristics of oral PMNs （oPMNs） compared with circulatory PMNs （cPMNs）. Oral rinse and venous blood samples were obtained from 268 systemically and orally healthy volunteers in a cross-sectional observational study. PMN counts, cell cycle analysis and cellular activation state were investigated. Also, reactive oxygen species （ROS） production was analyzed, with and without bacterial stimulation （Fusobacterium nucleatum）. In males, 1.2 × 10^6- 1.0 ×10^6 oPMNs were collected, and showed a tendency to correlate with the levels of gingival bleeding （r= 0.215, P= 0.008）. Comparable oPMNs counts were found among females （1.0 ×10^6＋ 0.7 × 10^6）. More late-stage apoptotic/necrotic cells were found among the oPMNs （53.1%） compared with the cPMNs （8.5%; P〈 0.001）. Without additional stimulation, oPMNs were more activated than cPMNs, as indicated by higher expression of CD11b, CD63 and CD66b, and higher constitutive ROS levels （P〈 0.001）. Notably, in response to bacterial stimulation, oPMNs released comparable ROS levels as cPMNs （P= 0.042）. In conclusion, this study provides data on viable oPMNs showing high levels of activation in orally and systemically healthy individuals, free of apparent caries lesions and periodontal disease. These data suggests that although the oPMNs are in a more mature stage of their life cycle compared with the cPMNs, oPMNs are still responsive to stimulation, which indicates their functional potential and possible contribution to a healthy oral ecosystem.

关键词： apoptosis degranulation neutrophils oral health reactive oxygen species

Characterization of C-N Thin Films Prepared by Ion Beam Sputtering

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Journal of Materials Science & Technology 1996年第4期12卷 312-314页

作者： Tian, YJ Ren, XJ Yu, DL He, JL Chen, SZ Li, dc Yu, RC Zhang, M Wang, WK CHINESE ACAD SCI INST PHYSBEIJING 100080PEOPLES R CHINA

C-N thin films have been prepared by ion beam sputtering using pure N-2 as discharge gas. The ratio N/C of the films measured by Auger spectrum is 20% on an average. The results of X-ray diffraction and transmission electron microscopy show that beta-C3N4. phase exists in the films. X-ray photoelectron spectroscopy shows that nitrogen is mostly combined with carbon with triple (C=N) and double (C=N) bonds. The IR absorption shows an absorption bond near 2185 cm(-1) assigned to the C=N, no trace of C-C bond was observed.

关键词： Thin films

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LDA测量方截面U型旋转通道速度分布

推进技术 2001年第3期22卷 261-264页

作者：吉洪湖 LAUNDER BE JACKSON dc 南京航空航天大学能源与动力学院江苏南京210016 Mechanical Engineering Dept. UMIST Manchester

为了深入了解旋转涡轮叶片内冷通道中的流动特性 ,用激光多谱勒测速仪 (LDA)测量了旋转U型通道中的平均速度分布。通道的横截面积为 5 0mm× 5 0mm ,弯管的平均半径与水利直径的比值为 0 6 5 ,旋转轴与弯管的曲率轴平行。在Re=10 5 时... 详细信息

为了深入了解旋转涡轮叶片内冷通道中的流动特性 ,用激光多谱勒测速仪 (LDA)测量了旋转U型通道中的平均速度分布。通道的横截面积为 5 0mm× 5 0mm ,弯管的平均半径与水利直径的比值为 0 6 5 ,旋转轴与弯管的曲率轴平行。在Re=10 5 时分别测量了转动数Ro =0 ,0 2和 - 0 2三种旋转状态下的速度分布。在这三种情况下弯管内侧θ =90°至下游一定范围内都有流动的分离出现。由于不同的旋转状态二次流的方向和强弱不同 ,导致了分离区大小和通道中速度分布的不同。

关键词：湍流旋转流体流速测量激光多普勒速度计 LDA 燃气涡轮发动机飞行器

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光盘刻录机使用技巧

微型计算机 2000年第13期20卷 63-67页

作者： Yane,dc

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Internet上的桌面视讯会议系统

微型计算机 1998年第12期18卷 87-91页

作者： Yane,dc

SEDIMENT DAMAGES AND RECENT TRENDSIN THE UNITED STATES

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International Journal of Sediment Research 2000年第2期15卷 135-148页

作者： Jerry M. Bernard (National Geologist) Thomas A. Iivari(Senior Hydrologist, United States Department of Agriculture-Natura ResourcesConservation Service, Washington, dc) United States Dept. of Agriculture Nat. Resources Conservation Service Washington DC United States

In the United States, cropland erosion has decreased by an estimated one billion tons or 42 Percent for the period 1982 to 1997 (USDA NRCS, 1998) through erosion reduction provisions of the Food Security Actof 1985 and the ongoing soil conservation programs administered by the United States Department ofAgriculture’s Soil Conservation Service (USDA-SCS), which became the Natural Resources ConservationService (USDA-NRCS) in *** U.S. Geological Survey has measured suspended sediment loads at strearn gages from 198O through1989 and showed primarily decreases of from 1 to 12 percent for most regions and increases for only threeregions, ranging from 2 to l2 percent.A Reservoir Sediment Information System (RESIS) was created so that decades of dare on reservoir sediment deposits could be evaluated (Atwood, 1994, Steffen, 1994; Atwood and Steffen, 1994). Theresults of analyses show a major increase in unit-area sediment deposition rates during the period 1970through 1985, which may be attributable to increased cropland acreage, a switch from diversified farming tointensive monocultUred crops, with widespread adoption of soybeans. The most recent measured ratesshow that 25 percent of the United States reservoirs would be at least half-filled with sediment by 2O18,although there is a significant data gap since 1985. Relatively few reservoirs were surveyed since 1985 dueto lack of funding priority and increased survey labor costs.

关键词： Cropland erosion Soil conservation program Suspended sediment Reservoir sediment information system