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1.
A. Khalique Munir H. Shah M. Jaffar N. Shaheen S. Manzoor Saadia R. Tariq 《人类与生态风险评估》2005,11(5):1065-1075
Scalp hair samples of traffic control personnel (n = 71, ages between 25 to 45 years) were analyzed for 11 selected metals by using an Inductively Coupled Argon Plasma Atomic Emission (ICP-AE) technique using nitric acid–perchloric acid based wet digestion method. The observed order of mean concentrations (μ g/g, dry weight) of the metals, in washed hair samples, was: Ca > Mg > Zn > Fe > Pb > Cu > Ni > Mn > Cr > Cd > Co, with corresponding metal levels at 1042.2, 182.4, 169.7, 13.6, 12.4, 11.1, 2.7, 1.9, 1.9, 0.8, and 0.7 μ g/g, respectively. Most of the unwashed samples exhibited 10–15% higher metal levels compared with those in washed samples. A positive metal-to-metal correlation (p < 0.01) was observed for the metal pairs: Ca-Mg (r = 0.737), Pb-Cr (r = 0.441), and Cu-Zn (0.385). Principal Component Analysis (PCA) extracted 6 factors as metals origin using varimax normalized rotation commutatively representing more than 76% of the total variance. Cluster Analysis (CA) showed five strong clusters of selected metals in the hair of the subjects: Age-Exposure, Ca-Mg, Cd-Fe-Mn, Pb-Cr, and Cu-Zn. The results of the current study were compared with those for two other occupationally exposed groups, metal arc welders and autodrivers, using published literature values. The traffic controllers in our study generally, with the exception of Cu, exhibited lower levels of metals in hair samples than did autodrivers and arc welders. 相似文献
2.
The plasmas of breast cancer patients and healthy donors were analyzed for selected trace metals by a flame atomic absorption spectrophotometric method. In the plasma of breast cancer patients, mean concentrations of macronutrients/essential metals, Na, K, Ca, Mg, Fe, and Zn were 3584, 197.0, 30.80, 6.740, 5.266, and 6.170 ppm, respectively, while the mean metal levels in the plasma of healthy donors were 3908, 151.0, 72.40, 17.70, 6.613, and 2.461 ppm, respectively. Average concentrations of Cd, Cr, Cu, Mn, Ni, Pb, Sb, Sr, and Zn were noted to be significantly higher in the plasma of breast cancer patients compared with healthy donors. Very strong mutual correlations (r > 0.70) in the plasma of breast cancer patients were observed between Cd–Pb, Cr–Li, Li–K, Li–Cd, K–Cr, Li–Pb, Cr–Co, Cu–Ni, Co–K, Cd–K, and K–Pb, whereas, Al–Cr, Ca–Zn, Cd–Sb, Cd–Zn, Ca–Mg, Fe–Zn, and Na–Mn exhibited strong relationships (r > 0.60) in the plasma of healthy donors. The cluster analysis revealed considerably different apportionment of trace metals in the two groups of donors. The average metal concentrations of different age groups of the two donor categories were also evaluated, which showed the build-up of Al, Cd, Co, Cr, Mn, Li, Pb, Sb, and Zn in the plasma of breast cancer patients. The role of some trace metals in carcinogenesis is also discussed. The study indicated appreciably different patterns of metal distribution and correlation in the plasma of breast cancer patients in comparison with the healthy population. 相似文献
3.
Selected trace metals were analyzed in human malignant and nonmalignant (benign) breast tissue samples by the flame atomic absorption spectrophotometric method. In malignant tissues, dominant mean concentrations were revealed by Na, K, Ca, Mg, Fe, Zn, and Al at 927, 552, 231, 61.7, 36.5, 18.3, and 8.94 microg/g, respectively, while the mean metal levels in benign tissues were 903, 435, 183, 63.3, 24.7, 14.5, and 10.1 microg/g, respectively. Average concentrations of Cd, Co, Cr, Cu, Fe, Mn, K, Ca, and Zn were noted to be significantly higher in the malignant tissues compared with the benign tissues. Significantly strong correlations (r > 0.50) in malignant tissues were observed between Mn and Co, Mn and Cd, Cd and Cr, Fe and Mn, Cd and Co, Fe and Co, Mg and Pb, Cd and Fe, Mg and Ni, Pb and Ni, Ni and Sr, and Fe and Pb, whereas, Cd and Co, Cd and Mn, Co and Mg, Co and Mn, Cu and Mn, Co and Ni, Mg and Ni, Cd and Cu, Cd and Ni, Ca and Mg, Mn and Pb, Cu and Ni, Fe and Ni, Cd and Mg, Co and Cu, Cr and Na, and Cd and Cr revealed strong and significant relationships in benign tissues at p < 0.001. Principal component analysis of the metals data yielded six principal components for malignant tissues and five principal components for benign tissues, with considerably different loadings, duly supported by cluster analysis. The study revealed a considerably different pattern of distribution and mutual correlations of trace metals in the breast tissues of benign and cancerous patients. 相似文献
4.
Lung cancer is seriously threatening human health and exposure to trace metals is the most important aetiology for lung cancer. Selected essential/toxic metals (Ca, Mg, Na, K, Fe, Zn, Cu, Sr, Li, Co, Mn, Ni, Cr, Cd and Pb) are measured in the scalp hair and nails of lung cancer patients and controls by atomic absorption spectrophotometric method employing nitric acid-perchloric acid-based wet digestion. Average concentrations of Pb, Cd, Mn, Co and Cu are found to be significantly higher (p?<?0.05) in the scalp hair and nails of lung cancer patients compared with the controls, however, appreciably higher concentrations of Zn, Ca, Na, Mg and Cr are noted in the scalp hair of the controls. Most of the metal levels reveal higher dispersion and asymmetry in the scalp hair/nails of the patients compared with the controls. Average metal levels are also compared to investigate probable differences based on sex, abode, food and smoking habits. The correlation study shows significantly diverse mutual variations of the metals in the scalp hair and nails of the patients and controls. Considerable variations in the metal levels are also noted for various stages and types of lung cancer (adenocarcinoma, squamous cell carcinoma, large cell carcinoma and small cell lung cancer). Multivariate apportionment of the metals in the scalp hair and nails of the patients and controls are also significantly diverse. The study reveals considerably divergent variations in the metal levels in lung cancer patients in comparison with healthy subjects. 相似文献
5.
Kazi TG Jalbani N Kazi N Arain MB Jamali MK Afridi HI Kandhro GA Sarfraz RA Shah AQ Ansari R 《Biological trace element research》2009,127(1):16-27
The determination of toxic metals (TMs) in the biological samples of human beings is an important clinical screening procedure.
The aim of this work is to determine total content of TMs, aluminum (Al), cadmium (Cd), nickel (Ni), and lead (Pb) in scalp
hair samples of chronic kidney male patients (CKPs) on maintenance hemodialysis, during the period of 2005–2007. The study
included 115 CKPs (all smokers) and 150 controls or referents [82 (nonsmokers) and 68 (smokers)]. Both controls and patients
(males) were of the same age group (ranged 25–55 years), socioeconomic status, localities, and dietary habits. The scalp hair
samples were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy
of the total Al, Cd, Ni, and Pb measurements was tested by simultaneously analyzing certified reference material (human hair
NCS ZC81002). No significant differences were observed between the analytical results and the certified values (paired t test at p > 0.05). The levels of TMs in scalp hair samples of patients were found to be higher as compared to control nonsmoker and
smokers. Moreover, the study shows that levels of Al, Cd, Ni, and Pb in scalp hair samples may be useful to evaluate the impact
of cigarette smoking in kidney failure patients. 相似文献
6.
The present study deals with the plausible association between the trace elemental imbalances and the emergence of valvular heart disease (VHD). A total of 14 elements including Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr and Zn in the scalp hair of VHD patients and healthy donors were analysed by flame atomic absorption spectrophometry employing wet acid digestion methodology. Median levels of Cu, Fe, Mg, Mn and Sr in the scalp hair of patients were significantly higher compared to those of the healthy donors, while the median concentrations of K and Na were found to be considerably higher in the scalp hair of the healthy donors. In addition, substantially elevated Cu/Zn value in patients indicated the prevalence of inflammatory processes inside the body. The correlation coefficients among the elements in the hair of VHD patients were significantly diverse compared to those of the healthy donors. Multivariate statistical methods showed noticeably dissimilar apportionment of the elements in the two groups. Variations in the elemental levels were also observed with gender, habitat, dietary/smoking habits and occupations of both donor groups. Overall, the study revealed significant imbalances among the essential and toxic elements in the scalp hair of VHD patients compared to those of the healthy subjects. 相似文献
7.
Concentration and distribution of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) were determined in 26 soil profiles (n = 78) of northern Kentucky in response to environmental concerns about increasing anthropogenic inputs in a fast-paced urbanizing area. The selected sites represent alluvial, glacial till or residual soils that have not received any biosolid- or industrial-waste applications. Mean concentrations of Zn (53.8 mg kg?1) and Ni (25.9 mg kg?1) were the highest in the soil profile, whereas Cd (0.21 mg kg?1) was present only in trace amounts. All metals were within the low to middle range of baseline concentrations reported for US soils, suggesting minimal anthropogenic inputs. The distribution of Cu, Cr, Ni, and Zn increased with soil depth, whereas Cd and Pb concentrations were unaffected throughout the soil profile. Alluvial soils had the highest overall metal accumulations, particularly in surface soil horizons, indicating potential metal enrichment through depositional processes. The presence of a fragipan horizon or depth to bedrock did not significantly affect metal retention. Single correlation and multiple regression analyses indicated OM and pH as the most influential soil parameters for metal retention, followed by cation exchange capacity (CEC) and CEC/clay. Single correlations among metals suggested strong covariance of Zn with most metals throughout the soil profile, but weaker for Pb and Ni. 相似文献
8.
Heart failure (HF) is the major of cause of mortality and morbidity in the developed world. Gene expression profiles of animal
model of heart failure have been used in number of studies to understand human cardiac disease. In this study, statistical methods
of analysing microarray data on cardiac tissues from dogs with pacing induced HF were used to identify differentially expressed
genes between normal and two abnormal tissues. The unsupervised techniques principal component analysis (PCA) and cluster
analysis were explored to distinguish between three different groups of 12 arrays and to separate the genes which are up regulated
in different conditions among 23912 genes in heart failure canines'' microarray data. It was found that out of 23912 genes, 1802
genes were differentially expressed in the three groups at 5% level of significance and 496 genes were differentially expressed at 1%
level of significance using one way analysis of variance (ANOVA). The genes clustered using PCA and clustering analysis were
explored in the paper to understand HF and a small number of differentially expressed genes related to HF were identified. 相似文献
9.
Mohamed A. Okbah Samir M. Nasr Naglaa F. Soliman Mohammed A. Khairy 《Soil & Sediment Contamination》2014,23(6):656-676
Trace metals concentrations in sediments from the Egyptian Mediterranean coast were determined to evaluate the levels of contamination. The highest concentrations of metals were generally found in the middle region of the coast. Sediment pollution assessment was carried out using Enrichment Factor (EF), Geoaccumulation Factor (Igeo), Contamination Factor (CF), Modified Degree of Contamination (mCd), and Pollution Load Index (PLI). Association of adverse effects to aquatic life was determined using the classification of sediments according to three sets of sediment quality guidelines. The mean EF values were found to fall in the following sequence: Cr > Pb > Ni > Zn > Cu > Mn. The results demonstrated that the EF of metals in the sediments of the middle region was lower than those recorded in the western region and Rafah Station at the eastern region; the difference in the EF levels was significantly correlated with Fe concentrations along the study area. Based on the average Igeo of target elements, the Egyptian Mediterranean coast could be considered not polluted with Cr, Cu, Mn, Ni, Pb, and Zn (Igeo ≤ 0). The modified degree of contamination was >1.5, indicating zero to very low contamination. The calculated PLI were less than 1, indicating only baseline levels of pollution. There were small differences between the results obtained with the three used SQGs. Highly significant correlations were found between the concentrations of Fe, Mn, Co, Cr, and Ni, suggesting similar sources and/or similar geochemical processes controlling the occurrence of these metals in the sediments. 相似文献
10.
Imbalances in the concentrations of trace metals have become an increasingly recognized source of infirmity worldwide particularly in the development of ischemia heart disease (IHD). Present study is intended to analyze the concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn in the blood and scalp hair of the patients and counterpart controls by flame atomic absorption spectrometry after wet-acid digestion. On the average, Cd, Co, Cr, Fe, K, Li, Mn, Na, and Pb revealed significantly elevated concentrations in the blood of the patients compared with the controls (p < 0.05), whereas mean levels of Ca, Cd, Fe, K, Li, Pb, and Sr in the scalp hair were significantly higher in the patients than the controls (p < 0.05). Most of the metals exhibited noticeable disparities in their concentrations based on gender, abode, dietary/smoking habits, and occupations of both donor groups. The correlation study and multivariate statistical analyses revealed some significantly divergent associations and apportionment of the metals in both donor groups. Overall, comparative variations of the metal contents in blood/scalp hair of the patients were significantly different than the controls; thus, evaluation of trace metals status may be indicative of pathological disorders, such as IHD. 相似文献
11.
头面部特征是人类学各人种进行分类的重要依据,在人类学的研究中被用作亲缘关系的证据。2006-2016年在四川、云南、西藏、贵州、海南、新疆、内蒙古共调查14个族群成人2989人(男性1434人,女性1555人)的16项头面部指标,比较这些族群头面部特征差异。研究结果如下:1)在男性族群中木雅人、尔苏人、临高人、白马人的面宽、头宽均较大。图瓦人、布里亚特人、摩梭人的面宽、头宽、形态面高、鼻高值均较大。僜人、革家人、莽人的面宽、头宽较小,而形态面高、鼻高值较大。空格人的面宽、头宽、形态面高、鼻高值均较小。2)在女性族群中图瓦人、布里亚特人的头宽、面宽、鼻高、耳上头高均较大。革家人、空格人的头宽、面宽、鼻高、耳上头高均较小。木雅人、尔苏人、八甲人、白马人、夏尔巴人的头宽、面宽较大,鼻高、耳上头高较小。僜人、克木人、莽人的头宽、面宽较小,而鼻高、耳上头高较大。3)头宽、容貌耳长跟纬度、年平均气温、年降雨量等环境因子相关性较高。4)通过聚类分析和主成分分析木雅人、尔苏人、白马人与羌族头面部特征比较接近。克木人与佤族头面部特征最为接近。革家人、僜人、莽人头面部特征比较接近。图瓦人、布里亚特人头面部... 相似文献
12.
燕麦种质资源主要农艺性状的遗传多样性分析 总被引:17,自引:1,他引:17
燕麦种质资源是燕麦育种的重要基础,对燕麦遗传多样性的研究不仅有助于种质资源的搜集、管理和利用,也有利于进行核心种质的研究。为了解不同地区燕麦种质资源在农艺性状上的遗传多样性,对74份皮、裸燕麦种质资源13个性状的遗传多样性进行了聚类分析与主成分分析。结果表明:各性状的遗传多样性指数较大,多样性指数最高的是主穗粒重,其次是千粒重和穗长;性状变异系数最大的是单株分蘖数,其后依次为单株粒重和主穗粒重,最小的为株高;根据品种间各性状的遗传差异,通过聚类分析将74份资源材料划分为5类,其中36份皮燕麦资源被分为2类,26份裸燕麦资源被分为2类,7份皮燕麦和5份裸燕麦被分为一类,其中,类群Ⅰ可作为高产育种目标的亲本,类群Ⅲ可作为粒型育种目标的亲本,类群Ⅳ、Ⅴ可作为株高和小穗等育种目标的亲本;8个数量性状主成分分析的结果表明,前4个主成分对变异的累计贡献率达86.27%,第一主成分反应产量,第二主成分反应粒型,第三、第四主成分分别反应分蘖数和株高。 相似文献
13.
This paper takes an air mass approach to investigating the influence of weather on pollen concentrations in the atmosphere in Sydney, Australia, by producing a synoptic classification of pollen concentrations measured in the Sydney Basin. This synoptic classification has been produced using multivariate statistical techniques including principal component analysis and cluster analysis, to assign days into meteorologically homogenous categories. Surface and upper air meteorological data for warm months (October-March) over a 10-year period were used as input into the statistical analyses. Eleven synoptic categories were found in Sydney during the warm months. Pollen concentrations for the total pollen load and five individual families measured over a 3.5-year period have been investigated for each of the synoptic categories. High pollen concentrations during the warm months in Sydney are found to be influenced by the presence of a region of low surface pressure located to the south of the continent, bringing fast dry westerly gradient winds to Sydney. It is envisaged that these results will be important from a pollen forecast and associated public health perspective. 相似文献
14.
中国薹草属黑穗薹草组的数量分类研究 总被引:1,自引:0,他引:1
对中国薹草属黑穗薹草组Sect.Racemosae及外类群冻原薹草组Sect.Frigidae共20种3变种采用38个形态特征进行了数量分类研究。聚类分析结果表明,黑穗薹草组应是一个自然分类群;支持了《中国植物志》将两对相似种:乌拉草(Carer meyeriana)与红原薹草(Carer hongyuanensis)、膨囊薹草(Carex lehmanii)与五台山薹草(Carex montis-wutaii)分别处理为种的观点。主成分分析结果表明,本组的分类特征较为稳定与集中,本组主成分分析散点图与聚类分析的分类结果大致吻合,并表明有关小坚果、果囊、鳞片、主茎叶和苞片的性状在本组的分类中起到了主要作用。 相似文献
15.
Multivariate analysis of the selected metals in the hair of cerebral palsy patients versus controls 总被引:1,自引:0,他引:1
Khalique A Shah MH Jaffar M Shaheen N Tariq SR Manzoor S 《Biological trace element research》2006,111(1-3):11-22
Seventeen metals were measured in scalp hair samples from cerebral palsy patients (CPPs) and controls. Samples were collected
from 95 CPPs and 93 controls. The nitric acid-perchloric acid wet digestion procedure was used for quantification of the selected
metals by flame atomic absorption spectrophotometry. The concentrations of Ag, Ca, Cd, Co, Cr, Li, and Mg were significantly
higher and those of Cu, Fe, K, Mn, Na, Ni, Pb, and Sb were lower in the hair of CPPs compared with controls. A strong positive
correlation was found between Ca and Mg in the hair of controls but not in that of CPPs. Antimony was found significantly
negative in terms of its correlation with Co and Cu in CPPs group but not in the controls. Principal component analysis (PCA)
of the data extracted seven factors for CPPs and six factors for controls. Cluster analysis (CA) was also used to support
the PCA results. The study evidenced some specific source of Mg and Sb in the hair of CPPs. 相似文献
16.
Hair levels of heavy metals and essential elements in Chinese children with autism spectrum disorder
BackgroundDisproportional heavy metals and essential elements were reported in children with autism spectrum disorder (ASD) that is obscure in etiology. Inevitably, the association is biased by diet and environmental factors.MethodsFifty pairs, one with ASD and the other living together from the same special school with cerebral palsy (CP), were recruited in Hangzhou (China), aged from 2 to 11 years old (74.0 % male). All samples were divided into two subgroups: preschool-aged (2–5 years old) and school-aged (6–10 years old). Heavy metals (As, Hg, Pb) and essential elements (Al, Ca, Cu, Mg, Mn, Zn) in hair were quantified by inductively coupled plasma mass spectrometry analysis and flame atomic absorption spectroscopy.ResultsThe children with ASD generally had lower hair levels of Mn (ASD 0.124 μg/g, CP 0.332 μg/g, P = 0.001) compared to the children with CP. After stratification for age, there were no significant differences detected in preschool-aged group. In school-aged group, the results exhibited the children with ASD had higher hair Pb (1.485 μg/g, 0.690 μg/g, P = 0.007) and Cu/Zn ratio (0.092, 0.060, P = 0.003), while hair Hg (0.254 μg/g, 0.353 μg/g, P = 0.016)、Mn (0.089 μg/g, 0.385 μg/g, P = 0.002)、Mg (17.81 μg/g, 24.53 μg/g, P = 0.014) and Zn (100.15 μg/g, 135.83 μg/g, P = 0.007) showed an opposite pattern.ConclusionsThese results suggest an imbalance of Mn in Chinese children with ASD. 相似文献
17.
目的黑线仓鼠白化突变系是一种新的实验动物模型,本研究旨在组织水平上观察黑线仓鼠与白化突变系皮肤组织中黑色素细胞的分布与定位,以揭示黑线仓鼠白化突变系发生的细胞学机制。方法本实验选择黑线仓鼠和白化突变系各6只,取背部皮肤,制备石蜡切片,分别采用多巴染色、多巴-甲苯胺蓝复染,光镜观察、拍照。结果 Dopa染色显示,在黑线仓鼠与白化突变系皮肤组织中均有成熟黑色素细胞的分布,主要存在于毛囊毛乳头中,且黑线仓鼠黑色素阳性区要明显高于白化突变系。结论黑线仓鼠的酪氨酸酶活性要高于白化突变系。 相似文献
18.
《Journal of trace elements in medicine and biology》2014,28(1):50-55
ProjectMeta-analysis of previous studies evaluating associations between content of elements sulphur (S), chlorine (Cl), potassium (K), iron (Fe), copper (Cu), zinc (Zn) and bromine (Br) in normal and cirrhotic autopsy liver tissue samples.ProcedureNormal liver samples from 45 Greenlandic Inuit, median age 60 years and from 71 Danes, median age 61 years. Cirrhotic liver samples from 27 Danes, median age 71 years. Element content was measured using X-ray fluorescence spectrometry. Statistics: Dual hierarchical clustering analysis, creating a dual dendrogram, one clustering element contents according to calculated similarities, one clustering elements according to correlation coefficients between the element contents, both using Euclidian distance and Ward Procedure.ResultsOne dendrogram separated subjects in 7 clusters showing no differences in ethnicity, gender or age. The analysis discriminated between elements in normal and cirrhotic livers. The other dendrogram clustered elements in four clusters: sulphur and chlorine; copper and bromine; potassium and zinc; iron. There were significant correlations between the elements in normal liver samples: S was associated with Cl, K, Br and Zn; Cl with S and Br; K with S, Br and Zn; Cu with Br. Zn with S and K. Br with S, Cl, K and Cu. Fe did not show significant associations with any other element.ConclusionsIn contrast to simple statistical methods, which analyses content of elements separately one by one, dual hierarchical clustering analysis incorporates all elements at the same time and can be used to examine the linkage and interplay between multiple elements in tissue samples. 相似文献
19.
The concentrations of As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sn, Tl, and V were determined in hair of 96 school children and in blood
of 144 adults living in the vicinity of a hazardous waste incinerator (HWI) (Constantí, Tarragona County, Catalonia, NE Spain).
The results were compared with those obtained in previous (1998 and 2002) surveys performed in the same area. Data were analyzed
in terms of age, sex, and specific place of residence. Current mean concentrations in hair ranged between not detected (ND)
(As, Be, and Tl) and 1.31 μg/g for Cr. In blood, Be, Hg, Mn, Sn, and Tl levels were under the respective detection limits.
The mean blood concentrations of the remaining elements ranged from 0.34 μg/dL for Cd, to 2.40 μg/dL for Pb. Significant differences
in hair and blood in relation to gender were only noted for Pb in blood. In general terms, metal concentrations in hair and
blood from subjects living in Tarragona County are lower than most levels reported for other countries in recent years. 相似文献
20.
The assignment of the 1H and 15Nnuclear magnetic resonance spectra of the Src-homology region 3 domain ofchicken brain -spectrin has been obtained. A set of solutionstructures has been determined from distance and dihedral angle restraints,which provide a reasonable representation of the protein structure insolution, as evaluated by a principal component analysis of the globalpairwise root-mean-square deviation (rmsd) in a large set of structuresconsisting of the refined and unrefined solution structures and the crystalstructure. The solution structure is well defined, with a lower degree ofconvergence between the structures in the loop regions than in the secondarystructure elements. The average pairwise rmsd between the 15 refinedsolution structures is 0.71 ± 0.13 Å for the backbone atoms and1.43 ± 0.14 Å for all heavy atoms. The solution structure isbasically the same as the crystal structure. The average rmsd between the 15refined solution structures and the crystal structure is 0.76 Å forthe backbone atoms and 1.45 ± 0.09 Å for all heavy atoms. Thereare, however, small differences probably caused by intermolecular contactsin the crystal structure. 相似文献