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1.
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   

2.
本研究应用女母回归法、公畜内女母回归法、半同胞相关法和单元内半同胞相关法对内蒙古阿尔巴斯白绒山羊的产绒量、绒厚、毛长、体重、绒伸直长度和细度等六个性状的遗传参数进行了估测。结果表明:(1)绒量遗传力介于0.26~0.45之间;绒厚遗传力介于0.33~0.56之间;毛长遗传力介于0.23~0.32之间;体重的遗传力介于0.1 6~0.36之间;绒伸直长度遗传力为0.24;绒细度的遗传力为0.14。(2)产绒量与绒厚、绒厚与毛长、长度与绒厚、长度与毛长的遗传相关分别介于0.33~0.79、0.51~0.69 、0.38~0.60、0.74~0.90之间,存在较强的正向遗传相关;绒量与毛长、绒量与体重、绒厚与体重、细度与绒厚、细度与绒量、细度与体重的遗传相关分别为0.11~0.38、0 .06~0.17、0.15~0.36、0.02~0.11、0.24~0.35、0.13~0.32之间,存在较弱的正向遗传相关;毛长与体重、长度与绒量、长度与体重、长度与细度、细度与毛长之间的遗传相关介于-0.14~-0.28、-0.09~-0.20、-0.18~-0.23、-0.27~-0.31、-0 .17~-0.28之间,存在中等偏弱的负向遗传相关。(3)绒量、绒厚、毛长、体重的重复率分别为0.42、0.27、0.59、0.18。  相似文献   

3.
Metal determination in human tissues is the most common application of biological monitoring for screening, diagnosis and assessment of metal exposures and their risks. Various biopsy-materials may be used. This paper deals with the quantitative determination of Cd, Pb, Cr, Mn, Fe, Ni, Cu, and Zn concentrations in nails of male subjects exposed to these metals alongwith their respective controls, while working in locomotive, carriage and roadways workshops, and lead battery factories. The levels of Cd, Pb, Cr, Mn, Fe, Ni, Cu and Zn in fingernails, assayed by atomic absorption spectrophotometry, were compared with their respective controls by student ‘t’ test. All the obtained values were correlated to the personal and medical history of the subjects under study. Significantly high levels of Cd, Pb, Cr, Fe, Ni, Cu and Zn were present in smokers, compared to nonsmokers. The concentrations of Cd, Pb, Cr, Mn and Fe were not significantly high in vegetarian subjects. It was also observed that there is no contribution of liquor towards nail-metal concentration. Significant correlations were observed between skin disease and Cr, Mn, Fe, Cu; hypertension and Cd, Mn, Cu; mental stress and Cd, Pb, Mn, Ni, Cu, Zn; diabetes and Cr, Mn, Ni; chest pain and Pb; respiratory trouble and Cr, Mn, Fe, Ni, Zn; tuberculosis and Zn; acidity and Cd; and ophthalmic problems and Mn, Fe, Ni, and Zn  相似文献   

4.
落叶松人工林施肥对土壤酶和微生物的影响   总被引:17,自引:2,他引:15  
陈立新 《应用生态学报》2004,15(6):1000-1004
以落叶松(Larix gmelinii)二代1年、一代14年和34年人工林为研究对象,对林地进行了不同施肥实验处理.结果表明,施肥能不同程度地促进或抑制土壤酶活性和土壤微生物数量,尤其是对根际土壤生理活性影响效果更为明显.相同处理对不同发育阶段土壤酶活性和土壤微生物数量的影响效果不同.二代1年生幼林地最佳施肥方案是处理9,其土壤过氧化氢酶活性、蛋白酶活性、多酚氧化酶活性、脲酶活性、蔗糖酶活性、微生物总量、细菌数量、放线菌数量和真菌数量分别比对照提高413.49%、22.10%、20.56%、220.00%、49.46%、238.88%、247.24%、106.70%和366.67%;一代34年生最佳施肥方案是处理5。根际与非根际土壤过氧化氢酶、蛋白酶、多酚氧化酶、脲酶和蔗糖酶活性、微生物总量、细菌数量、真菌数量分别比对照提高30.44%、16.91%、0.22%、43.06%、124.18%、119.92%、87.66%、17.57%、24.55%、77.01%、168.62%、251.85%、183.33%、250.0%、38.24%和128.57%;一代14年生幼龄林需要适量的氮肥和有机无机混合肥,较理想的施肥方案为处理2和处理9,处理2根际与非根际土壤过氧化氢酶活性、蛋白酶活性、脲酶活性分别比对照提高44.39%、94.83%、4.62%、13.98%、10.70%和129.76%.处理9根际与非根际土壤微生物总量、细菌数量、真菌数量分别比对照增加176.49%、266.63%、198.04%、275.56%、66.67%和143.75%.  相似文献   

5.
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...  相似文献   

6.
7.
Wei XL  Lei P  Shi WY 《应用生态学报》2010,21(8):2086-2091
采用恒温土壤培养方法,研究了4种不同鱼蛋白有机液肥施用量[0(对照)、0.5、1.5、2.5 ml·kg-1]条件下小粉土酶活性和微生物生物量碳、氮的变化,及其与土壤养分的相关关系.结果表明:在整个培养过程中,不同鱼蛋白有机液肥施用量处理下土壤pH值变化范围为7.07~7.31,与对照无显著差异;土壤磷酸酶活性显著增强,分别为对照的1.27、1.90、1.96倍;土壤脲酶活性分别比对照提高39.81%、78.06%、173.24%;蛋白酶活性比对照提高56.37%、108.29%、199.98%;土壤微生物生物量碳、氮均随肥料添加量的增加而逐渐增大,分别为对照的1.67、3.95、4.74倍和1.21、2.43、4.06倍.土壤脲酶和蛋白酶活性以及土壤微生物生物量碳、氮在不同施用量处理下达到峰值点的时间不同.土壤磷酸酶、脲酶和蛋白酶活性、土壤微生物生物量碳、氮与土壤养分均呈显著正相关.施用鱼蛋白有机液肥可以显著促进小粉土微生物的生长及酶活性的提高,从而促进土壤有机质的分解转化和速效养分的释放.  相似文献   

8.
四氯乙烯和镉对草鱼的单一与联合毒性效应   总被引:9,自引:0,他引:9  
以静水生物测试法研究了四氯乙烯和重金属镉对草鱼的单一与联合毒性,同时采用Marking相加指数法对二者的联合毒性进行了评价.单一毒性试验表明:四氯乙烯对草鱼24、48、72和96 h的半数致死浓度(LC50)分别为49.12、41.68、36.37和34.30 mg·L-1;镉对草鱼24、48、72和96h的LC50分别为45.58、34.81、28.63和24.05mg·L-1;二者对草鱼均有毒性,而且为高毒,镉的毒性大于四氯乙烯.联合毒性试验表明:二者毒性比为1∶1,暴露时间为24、48、72和96 h时四氯乙烯和镉的LC50分别为24.63、12.54、9.88和7.08 mg·L-1以及17.11、8.71、6.87和4.92 mg·L-1,相加指数AI(additive index)分别为0.14、0.81、0.95和1.43,联合作用结果为协同效应,并且随着时间的增加,协同作用增强;二者浓度比为1∶1, 暴露时间为24、48 、72和96 h时四氯乙烯和镉的LC50分别为17.00、11.18、10.61和9.19 mg·L-1,AI分别为0.39、0.70、0.51和0.54,联合作用为协同作用.  相似文献   

9.
The levels of bioactive anthocyanins in the fruits of Amelanchier alnifolia, A. arborea and A. canadensis have been determined by HPLC. Cyanidin 3-galactoside (1) was present in the fresh fruit of the three species at concentrations of 155, 390 and 165 mg/100 g, respectively. Cyanidin 3-glucoside (2) was present only in A. alnifolia and A. canadensis at concentrations of 54 and 48 mg/100 g, respectively. The anthocyanins were confirmed by LC-ESI/MS and NMR studies. At 100 ppm, anthocyanin mixtures from the three species inhibited cyclo-oxygenase (COX)-1 and -2 enzymes at 66 and 67%, 60 and 72%, and 51 and 76%, respectively. The positive controls used in the COX assays were aspirin, Celebrex and Vioxx at 180, 1.67 and 1.67 ppm, respectively, and showed 74 and 69%, 5 and 82% and 0 and 85% COX-1 and COX-2 inhibition, respectively. Anthocyanins 1 and 2 and cyanidin (3) inhibited COX-1 enzyme 50.5, 45.62 and 96.36%, respectively, at 100 ppm, whereas COX-2 inhibition was the highest for 3 at 75%. In the lipid peroxidation inhibitory assay, anthocyanin mixtures at 10 ppm from the three species showed activities of 72, 73 and 68%, respectively, compared with 89, 87 and 98% for commercial anti-oxidants butylated hydoxyanisole, butylated hydroxytoluene, and tert-butylhydroxyquinone at 1.67, 2.2 and 1.67 ppm, respectively. At 10 ppm, compounds 1-3 inhibited lipid peroxidation by 70, 75 and 78%, respectively.  相似文献   

10.
The ontogenetic trends in the expression of 25 isozymes in liver, gizzard, heart, and pectoralis muscle of White Leghorn chickens were examined using starch gel electrophoresis. Little change in expression during development was evident in liver S-AAT-A, GPI-A, S-ICDH-A, S-MDH-A and M-MDH-A, in gizzard S-ACON-A, ADH-A, GPI-A, HK-1, HK-3, ME-A PEP-1, and PGM-A, in heart ADH-A, HK-1, HK-3, ME-A, PEP-2, PGM-A, and LDH-A, in pectoralis M-ACON-A, S-ACON-A, ADH-A, HK-1, HK-3, ME-A, PEP-2, and PGM-A, and in liver, gizzard, and heart M-ACON-A, ALD-A, CK-A, G3PDH-A, HK-1, and PGDH-A. Increasing levels of activity were demonstrated in liver ADH-A, ME-A, and PEP-2, in heart M-MDH-A, S-ICDH-A, M-ICDH, and M-AAT-A, and in pectoralis LDH-A, LDH-B, G3PDH-3, ALD-A, CK-A, HK-2, and PGM-B. There was a decrease in the activity of HK-1 in liver and in PEP-1 and PGDH-A in pectoralis muscle throughout development. While CK-C is active in the embryonic pectoralis, CK-A is restricted to later developmental stages. Isozyme expressions in regions of the pectoralis containing fast and slow muscle fibers in 7-month-posthatch individuals were noted and found to be identical. The results underscore the need to use similar developmental stages and tissue samples in comparative electrophoretic studies of birds.This study was supported by Natural Sciences and Engineering Research Council of Canada Grant A9866 to J.P.B.  相似文献   

11.
【目的】对白背飞虱Sogatella furcifera唾液腺蛋白进行鉴定及功能注释分类,探究不同发育阶段和不同性别的白背飞虱唾液腺蛋白之间的区别与联系。【方法】麻醉白背飞虱若虫、雄成虫和雌成虫,解剖收集唾液腺组织,提取蛋白,还原烷基化和酶解,利用液相色谱串联质谱技术鉴定蛋白。与Unigene蛋白数据库进行比对,并通过KOG分析,对唾液腺蛋白进行功能注释分类。【结果】白背飞虱若虫、雄成虫和雌成虫特有的唾液腺蛋白分别为385, 168和82个,若虫与雄成虫、若虫与雌成虫及雄成虫与雌成虫共有的唾液腺蛋白分别为319, 60和60个。KOG功能注释显示与细胞过程和信号传导相关的蛋白数量最多,若虫、雄成虫和雌成虫特有以及若虫与雄成虫、若虫与雌成虫及雄成虫与雌成虫共有的这类蛋白数量分别为81, 22, 70, 19, 21和12个,这些蛋白主要发挥着翻译后修饰、蛋白质更新、伴侣蛋白,细胞内运输、分泌和囊泡运输及信号转导作用。【结论】白背飞虱唾液腺蛋白在参与信号转导机制方面表现较为活跃,这可能与其刺吸危害有一定的关系。  相似文献   

12.
Genetic, environmental and phenotypic correlations between libido, testicular measurements, body weight and semen traits were estimated by multiple-trait-restricted maximum likelihood (MTDFREML) under animal models. Reproductive records, collected from 1992 to 1997, of 288 Nellore bulls were used. Estimates of heritability for libido unadjusted, adjusted for scrotal circumference and adjusted for body weight, were 0.34 +/- 0.10, 0.31 +/- 0.10, and 0.19 +/- 0.11, respectively. Genetic correlations between libido and body weight, scrotal circumference, testis length, testis width, testis volume and testis consistency were, respectively, 0.69, -0.43, -0.31, -0.16, 0.10, 0.87, and between libido and semen volume, sperm motility, vigor, gross motility, major, minor and total defects were, respectively, 0.71, 0.51, 0.12, 0.16, 0.31, 0.26 and 0.43. Results suggested that selection for libido would be effective and that it would lead to desirable correlated response for scrotal circumference, physical and morphological semen traits and undesirable correlated response in body weight.  相似文献   

13.
南昌市不同植物类群叶片氮磷浓度及其化学计量比   总被引:11,自引:2,他引:9  
对南昌大学前湖校区89种主要植物叶片的N、P浓度及其化学计量比进行了研究,结果表明:乔灌、常绿、针叶、种子、裸子和单子叶植物类群的N浓度分别低于相对应的草本、落叶、阔叶、蕨类、被子和双子叶植物类群,而C3和C4植物差异不显著;乔灌、常绿和裸子植物类群的P浓度含量分别低于相对应的草本、落叶和被子植物类群,而针叶和阔叶、蕨类和种子、单子叶和双子叶、C3和C4植物类群间差异不显著;乔木、阔叶、被子和双子叶植物类群叶片N/P分别高于相对应的灌草、针叶、裸子和单子叶植物类群,而常绿和落叶、蕨类和种子、C3和C4植物类群之间差异不显著.可见,不同类型植物对N和P的吸收利用存在差异,且对不同养分供应采取不同的适应对策.结合研究区土壤养分现状,建议优先选择常绿、针叶、裸子和单子叶植物类群作为城市园林植物.  相似文献   

14.
边禄森  戴玉成 《生态学报》2015,35(5):1554-1563
对东喜马拉雅地区多孔菌区系和生态习性进行了分析,发现该地区多孔菌极为丰富,共有10目19科101属372种,其中优势科为多孔菌科和锈革孔菌科,优势属为木层孔菌属和多孔菌属。种的区系地理成分可以分为8类,其中北温带类型种类最多,表明东喜马拉雅地区多孔菌具有明显的北温带区系特征。该地区的多孔菌有常见种、偶见种、稀有种和濒危种分别为156、141、54和21个;有腐生菌304种、寄生菌49种、菌根菌19种。在寄主方面,能够生长在被子植物上的有256种,裸子植物上的有137种,既能生长在被子植物,也能生长在裸子植物上的有40种,地上生长的有19种。东喜马拉雅地区的裸子植物,特别是云杉属、松属和冷杉属树木对于多孔菌的生长更重要,因为生长在这些属树木上的多孔菌分别有71、68和51种,高于该地区被子植物其他属树木上的多孔菌。  相似文献   

15.
吴刚  冯宗炜  秦宜哲 《生态学报》1993,13(2):139-147
农林业系统沙兰杨-小麦、玉米群落类型N、P、K营养元素循环研究结果表明:在整个群落中,元素N和P发生损亏,K基本平衡。在植物组分库和枯落物库中,元素N、P、K均发生累积;在土壤库中,元素N、P和K均发生亏损。土壤表层(0—20cm)N的含量是限制农作物正常生长发育的主要环境因子。土壤库中有效N和速效P的含量是限制沙兰杨正常生长发育的主要环境因子。群落的年输入输出量大,枯落物少,营养元素在各组分间的循环量大等是该群落类型营养元素循环的重要特性。  相似文献   

16.
为探讨油茶(Camellia oleifera)产地土壤和油茶果实中金属元素分布和富集特征,在油茶果实成熟期,对浙江5个油茶产地土壤及油茶果实中金属元素进行污染分析和富集能力评价.结果表明,浙江油茶产地土壤中Pb、Cr、Cd、As、Hg、Ni、Cu和Zn含量低于农用地土壤污染风险筛选值,综合污染等级为安全.个别产区常山...  相似文献   

17.
Microbial reclamation of shellfish wastes for the production of chitinases   总被引:1,自引:0,他引:1  
Shrimp and crab shell powder (SCSP), prepared by treating shellfish processing waste with boiling and crushing, was used as a substrate for isolating chitinolytic microorganisms. Three potential strains (E1, J1, and J1-1) were isolated and identified as Bacillus cereus, B. alvei, and B. sphaericus, respectively. Three extracellular chitinases (FB1, FB2, and FB3) were purified from the culture supernatants of Bacillus cereus E1, B. alvei J1, and B. sphaericus J1-1, respectively. The molecular weights of FB1, FB2, and FB3 were 71,000, 71,000, and 65,000, respectively, by SDS-PAGE. The pIs for FB1, FB2, and FB3 were 7.1, 7.2, and 7.4, respectively. The optimum pH, optimum temperature, pH stability, and thermal stability of FB1 were pH 9, 50 degrees C, pH 7 to 10, and 70 degrees C; those of FB2 were pH 9, 60 degrees C, pH 5 to 9, and 70 degrees C; and those of FB3 were pH 7, 50 degrees C, pH 5 to 9, and 60 degrees C. The activities of all enzymes were strongly inhibited by Hg(2+) and completely inhibited by glutathione, dithiothreitol, and 2-mercaptoethanol.  相似文献   

18.
生态系统服务功能及其生态经济价值评价   总被引:509,自引:19,他引:490  
生态系统服务功能是指生态系统与生态过程所形成及所维持的人类赖以生存的自然环境条件与效用。它不仅为人类提供了食品、医药及其它生产生活原料,更重要的是维持了人类赖以生存的生命支持系统,维持生命物质的生物地化循环与水文循环,维持生物物种与遗传多样性,净化环境,维持大气化学的平衡与稳定。人们逐步认识到,生态服务功能是人类生存与现代文明的基础。近年来生态系统服务功能的研究已引起了人们的广泛重视,生态学家、经济学家纷纷探讨生态系统服务功能的内涵与定量评价方法,并已成为当前生态学与生态经济学研究的前沿课题。本文拟系统地分析生态系统服务功能的研究进展与趋势,生态系统服务功能价值的评估方法,并探讨生态系统服务功能及其与可持续发展研究的关系.  相似文献   

19.
Schistosomiasis is a major health problem in many subtropical developing countries, causing a number of serious pathologies, including bladder cancer. Most of the toxic compounds formed as a result of these infestations are derived either exogenously or formed endogenously and can be conjugated with glutathione (GSH) via glutathione S-transferase (GST). The present study investigates the effect of Schistosma haematobium infection on the activity of GST and glutathione reductase (GR) and levels of glutathione and free radicals (measured as thiobarbituric acid reactive substances) in different organs of the male hamster. The total activity of GST was increased in several organs; in kidney by 50 and 46% at 6 and 10 weeks postinfection, respectively, and in bladder tissues by 169, 23, and 130% at 2, 4, and 6 weeks postinfection, respectively. In support of this, the expression of GST isozymes was also induced in kidney and bladder tissues at early stages (2, 4, and 6 weeks) and reduced at the later stages of infection (8 and 10 weeks). In contrast, the expression of these isozymes was decreased in the spleen and liver at 2, 4, 6, 8, and 10 weeks postinfection. Also, such activity was decreased in lungs by 74 and 78% and in bladders by 65 and 72% at 8 and 10 weeks postinfection, respectively. GSH levels increased in lungs by 95, 40, and 56% at 2, 4, and 6 weeks and in spleen by 26 and 74% at 4 and 6 weeks, respectively, but decreased at later stages of S. haematobium infection in these organs. The depletion of GSH levels also occurred in bladders by 72 and 54% at 8 and 10 weeks postinfection, respectively. The activity of GR was increased in the livers, lungs, and kidneys of the S. haematobium-infected hamster. TBARS also increased in the lung by 14, 65, 53, 828, and 624% and in the kidney by 64, 29, 87, 190, and 111%, and in the bladder by 216, 23, 1468, 528, and 1025% at 2, 4, 6, 8, and 10 weeks postinfection, respectively. This study indicates that low GST expression and high levels of free radicals could provide new evidence for damage to the bladder and other organs as a result of S. haematobium infection.  相似文献   

20.
太湖梅梁湾漫衰减系数季节性差异及其主导因素   总被引:6,自引:0,他引:6  
利用2006-08-16、2007-3-28和2007-11-12三次在太湖梅梁湾15个样点的观测数据,对漫衰减系数(Kd)及其影响因素的时空差异性进行分析,发现:梅梁湾地区Kd的主要决定因素是总吸收系数,后向散射作用对Kd具有一定的影响作用,但非主导作用;梅梁湾地区水体Kd影响因素的主次关系并非固定不变,而是随着水体组分的季节性变化而变化,3月份Kd的主导影响因素是非色素物质,其次是有色可溶性有机物(CDOM)、色素物质和后向散射作用,而8月份的主导影响因素是色素物质,其次是非色素物质、CDOM和后向散射作用,而11月份相对较为复杂,在440nm处主导影响因素是非色素物质,其次是色素物质、CDOM和后向散射作用,595nm处主导影响因素是非色素物质吸收作用,其次是色素物质吸收作用、后向散射作用、CDOM吸收作用,675nm处主导影响因素是色素物质,其次是非色素物质、后向散射作用和CDOM.  相似文献   

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