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921.
922.
目的观察Snail mRNA及其蛋白、E-cadherin蛋白在胃癌组织中的表达及其与胃癌临床病理特征的关系,并探讨它们在胃癌发生、发展中的作用及其临床应用价值。方法收集96例手术切除胃癌标本,同时取80例癌旁组织作为对照。应用免疫组织化学S-P法检测胃癌组织、癌旁组织中snail蛋白、E-cadherin蛋白的表达;运用原位分子杂交技术检测胃癌组织、癌旁组织中Snail mRNA的表达。结果(1)Snail蛋白在胃癌组织阳性率(83.3%)显著高于癌旁组织(41.25%)(P〈0.05);高、中分化组Snail蛋白阳性表达率显著低于低分化组(P〈0.05);Snail蛋白的阳性表达率在乳头状腺癌、管状腺癌及低分化腺癌与黏液癌之间差异有显著性(P〈0.05);Snail蛋白的表达与胃癌浸润深度、淋巴结转移及远处转移有关(P〈0.05),与性别、年龄、肿瘤大小、肿瘤部位及临床分期无关(P〉0.05);(2)胃癌组织中snail mR-NA的阳性率(76%)显著高于癌旁组织(30%)(P〈0.05);高、中分化组Snail mRNA阳性表达率显著低于低分化组(P〈0.05);Snail mRNA的阳性表达率在乳头状腺癌、管状腺癌及低分化腺癌与黏液癌之间差异有显著性(P〈0.05);Snail mRNA的表达与浸润深度及淋巴结转移有关(P〈0.05),与性别、年龄、肿瘤大小、肿瘤部位、临床分期及远处转移无关(P〉0.05);(3)E-cadherin蛋白在胃癌组织阳性率(37.5%)显著低于癌旁组织(100%)(P〈0.05);高、中分化组E-cadherin蛋白阳性率显著高于低分化组(P〈0.05);E-cadherin蛋白阳性率在乳头状腺癌、管状腺癌及低分化腺癌与黏液癌之间差异有显著性(P〈0.05);E-cadherin蛋白的表达与胃癌浸润深度、淋巴结转移、临床分期及远处转移有关(P〈0.05),与性别、年龄、肿瘤大小、肿瘤部位均无关(P〉0.05);(4)胃癌组织中snail mRNA和snail蛋白的表达呈正相关(r=0.594,P〈0.05);Snail蛋白和E-cadherin蛋白的表达呈负相关(r=-0.234,P〈0.05)。结论(1)E-cadher-in蛋白低表达与Snail蛋白高表达可能是胃黏膜恶性转变以及胃癌发生浸润转移的重要生物学标志;联合检测E-cadherin蛋白与Snail蛋白对预测胃癌浸润转移有重要意义。(2)Snail蛋白可能在转录水平上调控E-cadherin蛋白的表达。 相似文献
923.
Evaluation of forest ecosystem services is a hot topic,both in China and at abroad,but it has not yet obtained a consistency of evaluation indicator systems and evaluation methods.Under the framework of evaluation criteria to be implemented for forest ecosystem services,years of consecutive observation data from Long Term Ecological Research Stations affiliated to Chinese Forest Ecosystem Research Network(CFERN),forest resource inventory and public data were applied to carry out a detailed and dynamic evaluation on the physical quantity and value of ecosystem services of Chinese pine forests in China.The results showed that the above services had the total value and unit value of 1144.9640 billion(1.1449640×10 12 )RMB and 52.074 thousand RMB per hectare per year,respectively during the 9th Five-year Plan(1996―2000),and of 1190.5461 billion RMB and 52.101 thousand RMB per hectare per year,respectively,during the 10th Five-year Plan(2001―2005).For Chinese pine forests,water conservation was 40.40 hundred million cubic meters annually,soil conservation was 67 million tons and C fixation 9 million tons annually,production of healthful negative ions was 1.96×10 20 , absorption of SO2 was 5.02 hundred million kilograms and dust-catching was 759.10 hundred million kilograms. Among the 15 provinces of China with Chinese pine forests,the biggest beneficiary from ecosystem services was Liaoning Province;while Hunan Province was the smallest beneficiary between the 9th Five-year Plan. 相似文献
924.
Valery A. Isidorov Paweł Lech Anna Żółciak Magdalena Rusak Lech Szczepaniak 《Trees - Structure and Function》2008,22(4):531-542
An investigation was carried out of the composition of metabolites in pine seedlings tissues at the initial stages of the
infectious process caused by pathogenic fungi Armillaria ostoyae, which causes a root rot of trees and degradation of forest resources. With the help of successive extraction with organic
solvents of different polarity, more than 190 metabolites were extracted from the needles and roots of the seedlings and then
identified by GC–MS method. The composition of the extracts from control plants and those inoculated with Armillaria ostoyae were compared. It was established that part of secondary metabolites (glucosamines and free amino acids, carbohydrates raffinose
and trehalose) were present only in the tissues of inoculated plants. Possible roles of some of these compounds appearing
in the roots of seedlings infected with the fungus are also discussed in the paper. 相似文献
925.
Xiao-Qi Zhang Chengdao Li Amy Tay Reg Lance Daryl Mares Judy Cheong Mehmet Cakir Junhong Ma Rudi Appels 《Molecular breeding : new strategies in plant improvement》2008,22(2):227-236
Pre-harvest sprouting (PHS) is a complex trait controlled by multiple genes with strong interaction between environment and
genotype that makes it difficult to select breeding materials by phenotypic assessment. One of the most important genes for
pre-harvest sprouting resistance is consistently identified on the long arm of chromosome 4A. The 4AL PHS tolerance gene has
therefore been targeted by Australian white-grained wheat breeders. A new robust PCR marker for the PHS QTL on wheat chromosome
4AL based on candidate genes search was developed in this study. The new marker was mapped on 4AL deletion bin 13-0.59-0.66
using 4AL deletion lines derived from Chinese Spring. This marker is located on 4AL between molecular markers Xbarc170 and Xwg622 in the doubled-haploid wheat population Cranbrook × Halberd. It was mapped between molecular markers Xbarc170 and Xgwm269 that have been previously shown to be closely linked to grain dormancy in the doubled haploid wheat population SW95-50213 × Cunningham
and was co-located with Xgwm269 in population Janz × AUS1408. This marker offers an additional efficient tool for marker-assisted selection of dormancy for
white-grained wheat breeding. Comparative analysis indicated that the wheat chromosome 4AL QTL for seed dormancy and PHS resistance
is homologous with the barley QTL on chromosome 5HL controlling seed dormancy and PHS resistance. This marker will facilitate
identification of the gene associated with the 4A QTL that controls a major component of grain dormancy and PHS resistance. 相似文献
926.
A. O. Bieńkowski 《Entomological Review》2008,88(4):435-441
Chrysolina (Semenowia) chalcea (Weise, 1889), Ch. (Pezocrosita) cyanopurpurea (Ballion, 1878), and Ch. (Chrysocrosita) fuyunica Chen, 1961 are redescribed. A male (topotype) of Ch. cyanopurpurea was examined for the first time. Ch. belousovi Lopatin, 2000 is a new junior synonym of Ch. cyanopurpurea; Ch. bienkowskii Lopatin, 2000 is a new junior synonym of Ch. chalcea. The taxonomic position of all the taxa mentioned is discussed. 相似文献
927.
Tomasz Podgórski Krzysztof Schmidt Rafał Kowalczyk Agnieszka Gulczyńska 《Acta theriologica》2008,53(2):97-110
We studied microhabitat selection of the Eurasian lynxLynx lynx (Linnaeus, 1758) at 116 hunting and 88 resting sites in Białowieża Primeval Forest (Poland) to describe its characteristics
and determine the importance of habitat structure for stalking prey and for security during resting. We identified lynx-used
sites by radio-tracking 3 male and 3 female lynx. When hunting, the lynx did not select for any type or age class of forest.
During both summer and winter, the lynx selected sites characterized by high complexity (number of structures useful for stalking:
fallen logs and branches, root plates, patches of dense bushes) and low visibility. In summer, hunting sites were often located
in the vicinity of small forest glades that provided good stalking opportunities for lynx and rich foraging resources for
roe deer — the main prey of lynx. The habitat at kill sites was more open than at sites where the prey was cached, with higher
visibility, lower density of trees and poorer undergrowth. The most important characteristic of resting sites was very low
visibility that resulted mainly from using young pine or spruce thickets in the winter and dense undergrowth of oak-lime-hornbeam
and ash-alder forests in the summer. The information provided by this study could have direct implications for Eurasian lynx
conservation by guiding forest restructuring to better suit the species’ biological requirements. 相似文献
928.
Ayhan Kocer Iris Pinheiro Maëlle Pannetier Lauriane Renault Pietro Parma Orietta Radi Kyung-Ah Kim Giovanna Camerino Eric Pailhoux 《BMC developmental biology》2008,8(1):36
Background
Up to now, two loci have been involved in XX sex-reversal in mammals following loss-of-function mutations, PIS (Polled Intersex Syndrome) in goats and R-spondin1 (RSPO1) in humans. Here, we analyze the possible interaction between these two factors during goat gonad development. Furthermore, since functional redundancy between different R-spondins may influence gonad development, we also studied the expression patterns of RSPO2, 3 and 4. 相似文献929.
Four new polyoxometalate compounds built on Preyssler anions and trivalent lanthanide cations, Na2[{Ce(H2O)8}4{Na(H2O)P5W30O110}] · 12H2O (1), H4Na4[Nd2(H2O)14{Na(H2O)P5W30O110}] · 22H2O (2), K2Na[Eu3(H2O)14(HNA)3{Eu(H2O)P5W30O110}] · 3H2O (3 NA = nicotinic acid) and H2[Ce4(H2O)16(HNA)6{Na(H2O)P5W30O110}] · 12H2O (4) have been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. Compound 1 exhibits a tetrasupporting polyoxometalate cluster structure where four {Ce(H2O)8}3+ fragments are supported on the [Na(H2O)P5W30O110]14− cluster. Compound 2 shows a one-dimensional chain structure built from [Na(H2O)P5W30O110]14− clusters linked by Nd3+ cations. Compound 3 displays a one-dimensional chain structure constructed of [Eu(H2O)P5W30O110]12− clusters bridged by Eu3+ cations. Compound 4 has a 2D network formed by 1D chains and {Ce2(H2O)6(HNA)6}6+ linkers. Compounds 2-4 represent the first extended structures based on Preyssler anions. In addition, the fluorescent activity of compound 3 is reported. 相似文献
930.
检测旋毛虫感染大鼠血清中的总IgE、特异性IgE和观察IgE介导的肥大细胞脱颗粒,并进一步探讨抗体依赖的(肥大)细胞介导的细胞毒性(Antibody dependent cell mediated cytotoxicity,ADCC)在旋毛虫病免疫机理中的作用。采用雄性Wistar大鼠为旋毛虫感染的动物模型,将90只大鼠随机分为10组。试验时,以ELISA双抗体夹心法和间接法分别动态检测总IgE和特异性IgE;肥大细胞脱颗粒试验采用直接法;然后采用细胞培养法观察免疫血清对肥大细胞杀伤旋毛虫肌幼虫作用的影响。在免疫血清存在时,无论感染鼠还是正常鼠的肥大细胞对旋毛虫幼虫均有杀伤作用,但以感染鼠的作用更强。肥大细胞在ADCC效应机制中对杀伤旋毛虫肌幼虫发挥了重要的作用。 相似文献