970 resultados para 860[82].07[Pueyrredón]


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目的:评价重离子束对皮肤恶性肿瘤放射治疗的近期疗效和毒副反应。方法:29例皮肤恶性肿瘤患者分6批接受重离子束放射治疗,其中恶性黑色素瘤13例,皮肤鳞癌及Bowen’s病各6例,基底细胞癌2例,其他皮肤恶性肿瘤2例。照射总剂量(50~70)GyE/(6~12)d,单次剂量5.5~11.67GyE,1f/d,连续治疗。采用RTOG标准和WHO近期疗效标准分别评价毒副反应和近期疗效。结果:截止2009-05,中位随访时间为13.5个月(1~25个月),随访率为100%。29例患者中完全缓解(CR)24例(82.8%),部分缓解(PR)5例(17.2%),有效率(RR)为100%,中位生存时间为22.8个月(95%CI:20.6~24.9)。皮肤反应0度11例(37.9%),Ⅰ度9例(31.0%),Ⅱ度6例(20.7%),Ⅲ度2例(6.9%),Ⅳ度1例(3.4%);血液毒副反应治疗前后无明显改变。结论:重离子束(12C6+)放射治疗皮肤恶性肿瘤近期疗效好,并发症轻,远期疗效、晚期副反应等尚需进一步长期全面的观察和更多的研究提供依据。

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Differential cross sections for the elastic scattering of halo nucleus He-6 on proton target were measured at 82.3 MeV/u. The experimental results are well reproduced by optical model calculations using global potential KD02 with a reduction of the depth of real volume part by a factor of 0.7. A systematic analysis shows that this behavior might be related to the weakly bound property of unstable nuclei.

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目的: 利用重离子辐照技术选育出对农作物具有更好防病促生作用的突变生防菌株,探讨利用突变株诱导黄瓜对枯萎病菌产生抗病性的作用机制。 材料与方法: 采用兰州重离子研究装置(HIRFL)加速的碳离子束辐照生防菌BJ1,测定抑菌能力、抑菌谱,确定对该菌株最适宜的离子辐照参数,选育突变菌株。对突变株进行室内盆栽和田间防病促生试验。对原菌株和突变株进行16SrDNA和生理生化反应鉴定,确定分类地位。以突变株为对象进行诱导黄瓜对枯萎病菌产生抗病性的实验。 结果与结论: 1.重离子辐照生防菌BJ1的存活曲线随剂量的增加,呈先降后升再降的马鞍型变化,但是由于离子的能量不同也存在差异,表现为在相同的剂量下,能量越低其能量沉积效应即传能线密度(LET)越大,致死率越高。诱变效果随LET的不同也不尽相同,高LET时的突变株不但有更广的抑菌谱而且抑菌活性较对照也有比较大的提高,在存活率较高的条件下,低剂量就可以得到较多的突变体,有利于筛选优良的正突变体; 2.对于生防菌BJ1最适宜的12C6+辐照参数应选择剂量在200-400Gy,LET为60keV/m范围可筛选获得抑菌活性较高的菌株; 3.通过12C辐照结合抑菌试验最终获得了突变菌株154,该突变株通过20代的移植能够稳定遗传; 4.利用突变株154对黄瓜枯萎病菌进行室内盆栽促生试验,结果表明突变株154能够使促进黄瓜幼苗的生长发育,同时提高了黄瓜植株的抗病性,在对黄瓜枯萎病的防治效果上经154处理的达到了70.34%,高于原菌株和农药防治的效果; 5.传统的生理生化特征结合16SrDNA同源性比对的方法,对菌株BJ1及其突变株154的鉴定结果表明二者均属枯草芽孢杆菌,亲缘关系近,但是突变株154生化测定不同于原菌株,表现为抗菌物质的产量较高; 6.BJ1、154都可在番茄、当归和黄芪的根部有效的定殖,适应根部的生长环境, 并且154的定殖能力稍强; 7.BJ1、154防治当归麻口病效果较好,防治效果最好的是154的20倍液浸苗,防效为82.6%;BJ1的20倍液浸苗与154的10倍液浸苗对麻口病防治效果差别不大,防效分别为78.3%、75.62%;其余处理防效低于62%。 8.BJ1和154处理黄瓜幼苗后,植物体内一系列与抗病性有关的保护酶的活性均有不同程度的提高,因而可认为这些酶活性的改变与生防菌诱导的黄瓜对枯萎病的抗性可能有一定的相关性

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The heat capacities (C-p) of three types of gasohol (which consisted of 20 wt % ethanol and 80 wt % unleaded gasoline 93(#) (system S1), 30 wt % ethanol and 70 wt % unleaded gasoline 931 (system S2), 40 wt % ethanol and 60 wt % unleaded gasoline 930 (system S3), where "93(#)" denotes the octane number) were measured by adiabatic calorimetry in the temperature range of 80320 K. A glass transition was observed at 94.24, 95.15, and 95.44 K for system S1, S2, and S3, respectively. A solid-solid phase transition and solid-liquid phase transition were observed at 135.18 and 151.30 K for system S1, 131.82 and 152.10 K for system S2, and 121.29 and 155.09 K for S3, respectively. The polynomial equations for C, with respect to the thermodynamic temperature (T), and with respect to the content of ethanol (x), were established through the least-squares fitting. The thermodynamic functions and the excess thermodynamic functions of the three samples were derived using these thermodynamic relationships and equations.

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A metal ions (Ag, Bi, V, Mo) modified sol-gel method was used to prepare a mesoporous Ag0.01Bi0.85V0.54Mo0.45O4 catalytic membrane which was used in the selective oxidation of propane to acrolein. By optimizing the preparation parameters, a thin and perfect catalytically active membrane was successfully prepared. SEM results showed that the membrane thickness is similar to5 mum. XRD results revealed that Ag0.01Bi0.85V0.54Mo0.45O4 with a Scheelite structure, which is catalytically active for the selective oxidation of propane to acrolein, was formed in the catalytic membrane only when AgBiVMoO concentrations were higher than 40%. Catalytic reaction results demonstrated that the selective oxidation of propane could be controlled to a certain degree, such as to acrolein, in the catalytic membrane reactor (CMR) compared to the fixed bed reactor (FBR). For example, a selectivity of 54.85% for acrolein in the liquid phase was obtained in the CMR, while only 8.31% was achieved in the FBR. (C) 2003 Elsevier B.V. All rights reserved.

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海岸带作为海陆之间的过渡地带,是全球生态环境最为复杂和特殊之处。研究海岸带土地利用变化对于了解该区域生态环境演变具有重要意义。利用1988和2000年的Landsat-TM数据,在GIS技术支持下,通过一系列空间分析,得到渤海海岸带土地利用/土地覆盖变化,结合社会经济统计资料分析该区域生态环境的动态变化情况及其驱动因素。结果表明,1988~2000年,由于渤海海岸带社会经济的快速发展,海岸带土地利用格局发生了巨大的变化。耕地大面积减少,城乡工矿用地、养殖池塘、盐田急剧扩张;林地、湿地等具有重要生态价值的土地类型面积显著下降。表明强烈的人类活动已经使自然生态系统受到破坏,渤海海岸带生态环境质量总体上呈现下降趋势。

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根据岷江上游地区自然地理环境条件的差别,将该区森林植被划分为暗针叶林、其它针叶林、阔叶林和灌木林等4个类型,利用年降雨量、林冠截流量数据、径流系数以及“影子价格”等方法,计算和评述了该区森林生态系统水源涵养效益;并利用遥感4期影像分析了岷江上游地区森林生态系统水源涵养量的变化原因。结果表明:2000年岷江上游森林生态系统年水源涵养量最高,为1·3892×1010m3,经济价值为93·07亿元。去除降雨量的影响后,在各时期年降雨量为705mm的情况下,岷江上游地区1986年的水源涵养量最高,为1·3348×1010m3,经济价值为89·43亿元;1995年水源涵养量下降,为1·2320×1010m3,经济价值为82·54亿元;2000年水源涵养量及经济价值与1995年基本持平。造成这一现象的主要原因是20世纪90年代岷江上游森林景观受到人为的严重破坏,而随后实施的“天然林保护工程”与“退耕还林还草”政策,加强了人工植被恢复建设,改善了森林生态系统,使森林生态系统水源涵养量有所恢复。

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本文根据农林复合系统中林分(以林带为主体)的特殊性,结合树木生长发育和林带结构变化规律,将农林复合系统中林分生长发育划分为幼龄期、中龄期(速生期)和防护成熟期。并采用林分径级离散度、防护成熟龄、更新龄等量化指标将3个生长发育时期定量化;对于东北地区农田林网中杂交杨、乡土杨的幼龄期为0~5、0~8,速生期6~15、9~24,实际防护成熟期16~33、25~36,防护成熟期16~自然成熟龄、25~自然成熟龄。同时给出各生长发育时期相应的经营措施。为农林复合系统中林木经营提供可靠的依据。

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基于2473个土壤剖面资料和1980年代末~1990年代末陆地卫星TM影像分析中国1990~2000年林地、草地、耕地之间的土地利用变化对土壤碳氮蓄积量的影响。IPCC建议的国家温室气体清单方法计算表明从1990~2000年中国林地、草地、耕地土壤(30cm)有机碳氮库分别损失了77.6±35.2TgC(1Tg=106t)和5.6±2.6TgN,年均损失约7.76TgC/yr和0.56TgN/yr,其中耕地土壤碳库分别增加了79.0±7.7TgC和9.0±0.7TgN,草地土壤碳氮蓄积量分别损失了100.7±25.9TgC和9.8±2.2TgN,林地土壤碳氮蓄积量分别损失了55.9±17.0TgC和4.9±1.1TgN。同时根据中国6大行政区林地、耕地和草地之间的相互转换面积、土壤有机碳氮密度的变化率进行估算,表明土壤(30cm和100cm)有机碳氮蓄积量分别损失了53.7TgC、5.1TgN和99.5TgC、9.4TgN。由于中国不同地区土地利用变化的空间格局差异显著,从而导致东北地区土壤碳氮蓄积量变化较大,而华东地区变化较小。

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(C5H9C5H4)(3)NdBrLi(THF)(4)(1)(C5H9=cyclopentyl) was obtained from the reaction of NdCl3 with C5H9C5H4Na and LiBr (Nd:Na:Li=1:2:1 molar ratio) in THE X-ray crystallography showed that the ten-coordinated neodymium atom is bonded to three cyclopentylcyclopentadienyl(eta(5)) rings and a single bromine atom bridging a lithium which is bonded to three THF molecules. Complex 1 is triclinic, P1 space group with unit dimensions of a= 12.048(2), b= 13.498(3), c= 13.831(3)Angstrom, a = 104.16(3), beta = 104.07(3), gamma =95.96(3)degrees, V=2083.3(7)Angstrom(3), Z=2, D-c=1.35Mg/m(3) and F(000)=874. (C5H9C5H4)(3)SmTHF (2) was synthesized by reaction of anhydrous SmCl3 with C5H9C5H4Na at a molar ratio of 1:3. The structure was determined by X-ray crystallography. The ten-coordinated samarium atom is bonded to three cycloperrtylcyclopentadienyl rings and one oxygen of THF molecule to form a pseudo-tetrahedron. Complex 2 is orthorhombic, Fdd2 space group with unit cell dimensions of a =28.175(5)Angstrom, b =46.24(2) Angstrom, c =9.167(4) Angstrom(3), V=11943(8)Angstrom(3), Z= 16, D-c = 1.38Mg/m(3) and F(000)=5136.

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无水三氯化钕与环戊烷基环戊二烯钠、溴化锂(1:2:1摩尔比)反应,除去不溶物和溶剂后,产物在己烷/四氢呋喃溶剂中冷冻得到兰紫色晶体(C5H9C5H4)3NdBrLi(THF)3(配合物1)。其中心金属Nd3+的配位数为10,以η5与3个环戊二烯基相连,并通过单溴原子桥连锂原子,形成双核结构。该晶体属三斜晶系,P`1空间群。晶体学参数为a=12.048(2)、b=13.498(3)、c=13.831(3);α=104.16(3)、β=104.07(3)、γ=95.96(3); V=2083.3(7)3、Z=2、Dc=1.35Mg/m3、Mr=847.01gmol-1、F(000)=874。无水三氯化钐与环戊烷基环戊二烯钠(1:3)反应,产物在-30oC下的己烷溶剂中结晶得桔红色晶体(C5H9C5H4)3SmTHF(配合物2)。该晶体属正交晶系,Fdd2空间群。晶胞参数a=28.175(5) 、b=46.24(2)、c=9.167(4);V=11943(8)3、Z=16、Dc=1.38Mg/m3、 Mr=622.11 g·mol-1、F(000)=5136。10配位的金属Sm3+与3个环戊二烯基以η5相连,并结合...

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Endohedral metallofullerenes Ce@C-82, Ce-2@C-80, Nd@C-82 and Nd-2@C-80 undergo gas phase ion/molecule reactions with the ion system from self-chemical ionization of vinyl acetate, and exohedral derivatives are thus generated, A new heterocycle is formed from metallofullerenes and a C2H3O+ cation, Endohedral metallofullerenes show much higher reactivities than empty fullerenes during the association and the charge and proton transfer processes, The strong electron-donating character of endohedral metallofullerenes is due to their unique super-atom-like electronic structures. (C) 1997 by John Wiley & Sons, Ltd.

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An on-line controlled 7 1 sterilizable photobioreactor was used for the optimisation of a culture of gametophytes of Undaria pinnatifida. The gametophytes, which had been stored for three years in a culture cabinet at 16 degreesC, could rapidly grow in the photobioreactor under controlled conditions. The rate of increase of dissolved oxygen and pH were used to monitor the photosynthetic activity. Optimal gametophytes density changed varying the light intensity. The optimal cell densities were 3.24 and 3.45 g FW l(-1) when the cultures were exposed to 61.7 and 82.3 muE m(-2) s(-1), respectively. The optimal cell density was higher under a high photon flux density (PFD) than under low PFD. On the other hand, the optimal light intensities were different for different cell density cultures. The light saturation point was higher at high cell density cultures than at low cell density cultures. The optimal rotational speed was 150 rpm for high cell density culture in the photobioreactor. (C) 2003 Elsevier B.V. All rights reserved.

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Calreticulin (CRT), as an endoplasmic reticulum luminal resident protein, plays important roles in Ca2+ homeostasis and molecular chaperoning. CRT on the surface of the cell can modulate cell adhesion, phagocytosis and integrin-dependent Ca2+ signaling. The full length cDNA of calreticulin (FcCRT) was cloned from Chinese shrimp Fenneropenaeus chinensis. It consists of 1672 by with an open reading frame of 1221 bp, encoding 406 amino acids. This is the first reported cDNA sequence of calreticulin in Crustacea. The deduced amino acid sequence of FcCRT showed high identity with those of Bombyx mori (88%), Drosophila melanogaster (83%), Mus musculus (82%) and Homo sapiens (82%). Highest expression of FcCRT was detected in ovary by Northern blot and in situ hybridization. Different mRNA levels of FcCRT were detected at various molting stages. Expression of FcCRT was induced significantly after 3 h of heat shock treatment, reached the maximum at 4 h and dropped after that. Differential expression profiles of FcCRT were observed in hepatopancreas and haemocytes when shrimp were challenged by white spot syndrome virus (WSSV). From the above results, we inferred that FcCRT might play important roles in Ca2+ homeostasis, chaperoning and immune function in shrimp. (c) 2007 Elsevier Inc. All rights reserved.

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C-type lectins are calcium-dependent carbohydrate-binding proteins that play Important roles in innate immunity In this study, a C-type lectin homologue (SmLec1) was identified from turbot (Scophthalmus maximus) and analyzed at expression and functional levels. The open reading frame of SmLec1 is 504 bp, with a 5'-untranslated region (UTR) of 101 bp and a 3'-UTR of 164 bp The deduced amino acid sequence of SmLec1 shares 34%-38% overall identities with the C-type lectins of several fish species In silico analysis identified in SmLec1 conserved C-type lectin features, including a carbohydrate-recognition domain, four disulfide bond-forming cysteine residues, and the mannose-type carbohydrate-binding motif In addition, SmLec1 possesses a putative signal peptide sequence and is predicted to be localized in the extracellular. Expression of SmLec1 was highest in liver and responded positively to experimental challenges with fish pathogens Recombinant SmLec1 (rSmLec1) purified from yeast was able to agglutinate the Gram-negative fish pathogen Listonella anguillarum but not the Gram-positive pathogen Streptococcus uncle The agglutinating ability of rSmLec1 was abolished in the presence of mannose and ethylenediaminetetraacetic acid and by elevated temperature (65 degrees C) Further analysis showed that rSmLec1 could stimulate kidney lymphocyte proliferation and enhance the killing of bacterial pathogen by macrophages Taken together, these results suggest that SmLec1 is a unique mannose-binding C-type lectin that possesses apparent immunomodulating property and is likely to be involved in host defense against bacterial infection (C) 2010 Elsevier Ltd. All rights reserved