首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
In this study, we determine bone strontium, barium, and calcium, as well as zinc, copper, and iron, in prehispanic samples belonging to adult individuals from the two main funerary caves from La Palma (Espigón and Barranco Porto), comparing them with our own modern controls. We have found that the Ba/Sr molar ratio of the individuals from Barranco Porto are significantly lower than that of the individuals from Espigón, thus suggesting a consumption of a marine-based diet by the former.  相似文献   

2.
Solution‐based inductively coupled plasma‐mass spectrometry was used to examine the effects of exposure time to ethanol (0, 1, 3, 9, 27 and 81 days) and ethanol quality (ACS‐ v . HPLC‐grade) on strontium (Sr) and barium (Ba) concentrations in sagittal otoliths of hatchery‐raised and wild‐caught young‐of‐the‐year walleye Stizostedion vitreum . No effect of either attribute on Sr and Ba concentrations were detected, indicating that metabolically inert elements that replace calcium in the calcium carbonate matrix ( e.g . Sr and Ba) are not influenced by storage in 95% ethanol.  相似文献   

3.
Concentrations of the 18 elements, barium (Ba), beryllium (Be), bismuth (Bi), calcium (Ca), cadmium (Cd), cesium (Cs), copper (Cu), lanthanum (La), lithium (Li), magnesium (Mg), molybdenum (Mo), lead (Pb), rubidium (Rb), antimony (Sb), tin (Sn), strontium (Sr), thallium (Tl), and zinc (Zn), were determined in the synovial fluids of osteoarthritic knee joints and in the corresponding sera of 16 patients by inductively coupled plasma-mass spectrometry. Knee-joint effusions have lower elemental concentrations than their corresponding sera. For the essential elements Ca, Cu, Mg, and Zn and for the nonessential and toxic elements Ba, Be, Bi, La, and Sb, this difference was highly significant. Strong positive correlations between concentrations in effusions and sera for the essential elements Cu and Mg and for the nonessential elements Cs, Li, Rb, and Sr could be established. The grade of localized hyperperfusion of the knee region in the blood pool phase of 99mTc HDP bone scan indicating inflammation did not correlate with any elemental concentration determined. Deceased.  相似文献   

4.
Zusammenfassung Das System Hydroxylapatitkristallite in einer geeigneten Lösung stellt in gewisser Hinsicht einin vitro-Analogon für den Knochenstoffwechsel der Erdalkalien dar. Es wird über Versuche berichtet, Unterschiede im Verhalten von Ca, Sr, Ba und Ra in synthetischem Hydroxylapatit festzustellen. Dazu wurden die Diskriminierungsfaktoren von Ca gegen Sr, Ba und Ra bei der Herstellung der Kristallite gemessen. Weiterhin wurde der Austausch der Erdalkalien zwischen vorgefertigten Kristalliten und einer geeigneten Lösung über eine Zeitdauer von 1000 h verfolgt. Die Diskriminierungsfaktoren nehmen mit zunehmender Ionengröße in der Reihenfolge Sr, Ba, Ra zu. Während Sr, Ca-Ionen auch im Inneren der Kristallite ersetzen kann, sind Ba und Ra fast ausschließlich auf die Oberfläche beschränkt. Für die Diskriminierung des Gesamtknochens muß angenommen werden, daß zusätzliche Prozesse eine Rolle spielen.
Studies on synthetic hydroxyapatite crystals with regard to metabolism of calcium, strontium, barium and radium, in boneI. The discrimination against calcium
Summary The system hydroxyapatite crystals in a proper solution, in a way, represents anin vitro analogue to metabolism of alkaline earths in bone. Experiments are described to find differencies in the behaviour of Ca, Sr, Ba and Ra to synthetic hydroxyapatite crystals. Synthesizing the crystals the discrimination ratios of Ca to Sr, Ba and Ra were measured. Furthermore the exchange of alkaline earths between preformed crystals and a proper solution was studied over a period of 1000 h. The discrimination ratios grow larger with increasing ionic radius in the order Sr, Ba, Ra. While Sr can replace Ca ions also in the interior of the crystals, Ba and Ra are limited to crystal surface. With respect to the discrimination of bone it must be concluded that further processes participate.
  相似文献   

5.
The use of freshwater habitats was examined in three amphidromous goby species of the genus Sicyopterus using otolith microchemistry. Two species were endemic to either New Caledonia or Vanuatu whilst the other was widely distributed. Depositional patterns of strontium (Sr) and barium (Ba) in the otolith of adults were analysed with femtosecond laser ablation inductively coupled plasma mass spectrometry (ICP-MS). The Sr:Ca and Ba:Ca results uncovered three different adult behaviours within the freshwater habitat. Some fishes stayed in elevated locations (square profile); others undertook back-and-forth migrations between higher and lower reaches (up-and-down profile), and finally, others stayed in the lower reaches (constant profile). The consequences of these movements to larval survival or competition for food and territory are discussed. This work brings new knowledge on amphidromous behaviour, and it highlights the necessity of multi-elemental analysis to study amphidromy in freshwater systems.  相似文献   

6.
The aims of the study were to determine manganese (Mn), iron (Fe) and strontium (Sr) concentrations in fox bone samples from north-western Poland and to examine the relationships between the bone Mn, Fe and Sr concentrations and the sex and age of the foxes. In the studied samples of fox cartilage, cartilage with adjacent compact bone, compact bone and spongy bone, the concentrations of the analysed metals had the following descending order: Fe > Sr > Mn. The only exception was in compact bone, in which the concentrations were arranged in the order Sr > Fe > Mn. Manganese concentrations were significantly higher in cartilage, compact bone and cartilage with compact bone than in spongy bone. Iron concentrations were higher in cartilage and spongy bone compared with compact bone. Strontium concentrations were greater in compact bone than in cartilage and spongy bone. The manganese, iron and strontium concentrations in the same type of bone material in many cases correlated with each other, with the strongest correlation (r?>?0.70) between Mn and Fe in almost all types of samples. In addition, concentrations of the same metals in different bone materials were closely correlated for Mn and Fe in cartilage and cartilage with adjacent compact bone, and for Sr in compact bone and cartilage with compact bone. In the fox from NW Poland, there were no statistically significant differences in Mn, Fe and Sr in any of the types of bone material between the sexes and immature and adult foxes.  相似文献   

7.
This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium (86Sr) and barium (137Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish.  相似文献   

8.
Sr/Ca and Ba/Ca ratios of bone are commonly used as biochemical indicators of trophic level in modern and fossil mammals. Concerns over the effects of diagenesis on Sr/Ca and Ba/Ca ratios of bone led archaeologists and paleontologists to favor tooth enamel, which is less prone to alteration. Sr/Ca and Ba/Ca ratios of bone, enamel, and dentin from three farm-raised steers (Bos taurus) and five wild white-tailed deer (Odocoileus virginianus) from central Missouri were compared. Our results show that changes in diet, discrimination, and growth rate during ontogeny can lead to significant differences in Sr/Ca and Ba/Ca ratios of different bioapatite types as well as significant differences within the same bioapatite forming at different times. Early- and late-forming tooth enamel can have significant differences in Sr/Ca and Ba/Ca ratios equivalent to almost one full trophic step. Although differences between early- and late-forming dentin are typically not significant, dentin Sr/Ca and Ba/Ca ratios are significantly greater than enamel values. This difference in Sr/Ca or Ba/Ca ratios between enamel and dentin from the same tooth can be greater than one full trophic step. These results have profound implications for the use of dental bioapatites in trophic level reconstructions. They highlight the importance of consistency in bioapatite selection, tooth selection, and relative location of sampling within the enamel cap. Furthermore, this expected difference in Sr/Ca and Ba/Ca ratios could be used as another means of checking for diagenetic alteration in ancient samples.  相似文献   

9.
The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus), two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr) and barium (Ba) showing the strongest correlation. The partition coefficients were 0.409–0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.  相似文献   

10.
11.
The variability and biologicalfractionation of Sr/Ca, Ba/Ca and 87Sr/86Srratios were studied in a soil–plant–invertebrate–bird food chain in two forested ecosystems withcontrasting calcium availability in the northeasternU.S.A. Chemical measurements were made of the soilexchange pool, leaves, caterpillars, snails, and boththe femurs and eggshells of breeding insectivorousmigratory songbirds. 87Sr/86Sr values weretransferred up the food chain from the soil exchangepool to leaves, caterpillars, snails and eggshellswithout modification. Adult birds were the oneexception; their 87Sr/86Sr values generallyreflected those of lower trophic levels at each site,but were lower and more variable, probably becausetheir strontium was derived in part from foods intropical winter habitats where lower87Sr/86Sr ratios are likely to predominate. Sr/Ca and Ba/Ca ratios decreased at each successive trophiclevel, supporting previous suggestions that Sr/Ca andBa/Ca ratios can be used to identify the trophic levelat which an organism is primarily feeding. The changesin Sr/Ca and Ba/Ca ratios we measured for vegetationand insects were comparable to similar measurementsmade previously (but based on single samples of eachorganism) in an alpine ecosystem. Changes in Sr/Ca andBa/Ca ratios between birds and their food have notpreviously been measured, but the values we obtainedwere similar to those for herbivorous and carnivorousmammals at similar trophic levels. Our results provideevidence that supports the use of Sr/Ca ratios in thedetermination of human paleodiets and suggests thatSr/Ca ratios may also provide a useful tool in studiesof modern food webs. Furthermore, our findings suggestthat 90Sr from nuclear fallout will notbioaccumulate in forests and that changes in Sr/Caratios between trophic levels will need to beconsidered in some cases when using87Sr/86Sr as a tracer of calciumbiogeochemistry.  相似文献   

12.
喇家遗址位于青海省民和县,主体为齐家文化的遗存,距今大约3900~4300年。喇家遗址古代人类迁移活动的研究,对于探索黄河上游古代文明,推动该地区齐家文化研究,有着积极的学术意义。本文首先采用电感耦合等离子体质谱技术对喇家遗址出土的22个个体的44份牙釉质和骨骼样品进行了元素分析,根据检测结果排除了受到污染的2份骨骼样品。其次,通过热电离质谱分析方法对喇家遗址出土22个个体的42份牙釉质和骨骼样品及8个猪牙釉质样品的锶同位素比值进行了测定。检测数据表明,猪牙釉质的锶同位素比值的标准偏差远小于其他动物,可以推断猪由当地饲养的可能性是最大的,因此其牙釉质锶同位素比值可以代表当地的锶同位素水平。经过计算得到8个猪牙釉质的锶同位素比值的平均值为0.710930,将该平均值加或减2倍标准偏差可以得到喇家遗址当地的锶同位素比值范围在0.711058~0.710802之间。以此为前提可以推测,本次检测的22个个体中,有17个个体牙釉质的锶同位素比值在遗址当地的锶同位素比值范围内,可能为本地出生。还有2个个体牙釉质在当地的锶同位素比值范围上下限附近,姑且存疑;仅有3个个体牙釉质的锶同位素比值在遗址当地的锶同位素比值范围以外,表明这些个体可能在其他地区出生,去世后埋葬在遗址中。此外,数据分析还显示,本地出生人群牙釉质的锶同位素比值平均值与骨骼的锶同位素比值平均值比较接近,暗示喇家遗址当地古人类生活方式可能比较统一。  相似文献   

13.
Alkali metals (AMs) and alkali earth metals (AEMs) affect levels and signaling of neurotransmitters, which potentially play a role in the etiology of schizophrenia (SCZ). The current case-control study aims to explore how AMs [i.e. Potassium (K), sodium (Na), rubidium (Rb), cesium (Cs)] and AEMs [i.e. magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba)] in serum could associate with SCZ. One hundred and five inpatients with SCZ and 106 age- and sex-matched healthy controls (HCs) were recruited from Weifang, China. Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was used to evaluate serum concentrations of Na, K, Ca, Mg and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was for Rb, Cs, Sr, Ba. Subjects with SCZ had significantly higher Mg and Sr serum concentrations than HCs (20.86 vs. 19.73 μg/mL of Mg, p < 0.001; 53.14 vs. 42.26 ng/mL of Sr, p < 0.001). After adjusting for confounders, the odds ratio of Mg and Sr remain significantly higher in the SCZ group (Mg: OR = 2.538, 95 % CI: 1.254–5.136, p=0.010; Sr: OR = 3.798, 95 % CI: 1.769–8.153, p = 0.001). No significant differences between SCZ subjects and HCs were observed for other AMs and AEMs. Higher serum concentrations of Mg and Sr were associated with SCZ. Studies are suggested to find the related mechanisms and provide clues for pathogenesis of SCZ, which would impact prevention and treatments of SCZ.  相似文献   

14.
Effect of Ca2+, Ba2+, and Sr2+ on alginate microbeads   总被引:7,自引:0,他引:7  
Microcapsules of alginate cross-linked with divalent ions are the most common system for cell immobilization. In this study, we wanted to characterize the effect of different alginates and cross-linking ions on important microcapsule properties. The dimensional stability and gel strength increased for high-G alginate gels when exchanging the traditional Ca2+ ions with Ba2+. The use of Ba2+ decreased the size of alginate beads and reduced the permeability to immunoglobulin G. Strontium gave gels with characteristics lying between calcium and barium. Interestingly, high-M alginate showed an opposite behavior in combination with barium and strontium as these beads were larger than beads of calcium-alginate and tended to swell more, also resulting in increased permeability. Binding studies revealed that different block structures in the alginate bind the ions to a different extent. More specifically, Ca2+ was found to bind to G- and MG-blocks, Ba2+ to G- and M-blocks, and Sr2+ to G-blocks solely.  相似文献   

15.
Strontium in archaeological human bones is widely, almost paradigmatically, used as a measure of the relative dietary abundances of plants and meat. Quantitative modeling reveals, however, that there is not a simple proportional relationship between bone strontium and the dietary plant/meat ratio. While knowledge of specific foods and their compositions may permit accurate calculation of average bone strontium levels, knowledge of bone strontium does not inversely allow accurate calculation of specific foods. Although bone strontium quantitatively reflects the average dietary Sr/Ca ratio, it is disproportionately sensitive to high-calcium foods and can be easily affected by minor dietary constituents and culinary practices. Bone strontium, and by analogy, barium, should be seen as a reflection of the high-mineral dietary components rather than a quantitative index of trophic position. © 1995 Wiley-Liss, Inc.  相似文献   

16.
西北太平洋柔鱼耳石微量元素   总被引:1,自引:0,他引:1  
耳石是头足类重要的硬组织之一,其微化学被用于头足类生活史的重建、群体划分等渔业生态学领域.本文根据我国鱿钓船2007年在西北太平洋海域生产期间采集的柔鱼样本,利用激光剥蚀电感等离子质谱法(laser ablation inductively coupled plasma mass spectrometry, LA-ICP-MS)分析了18枚柔鱼耳石的微量元素组成及其分布特性.结果表明: 柔鱼耳石主要由55种元素组成,含量最多的前10位元素分别为钙(Ca)、锶(Sr)、钠(Na)、磷(P)、钾(K)、硅(Si)、镁(Mg)、硼(B)、铁(Fe)和钡(Ba).方差分析表明,不同性别间柔鱼的Ca、Sr、Na、K、Mg、Fe、Ba的含量不存在显著性差异,但P、Si和B含量差异性明显;不同孵化期的群体间Sr和Na含量存在显著性差异,Ca、P、K、Si、Mg、B、Fe和Ba不存在显著性差异;不同耳石部位的Ca、Sr、Na、P、Mg和Ba含量存在显著性差异,而K、Fe、B和Si则不存在显著性差异.研究表明微量元素Sr和Na比较适合用于研究柔鱼的群体划分、洄游史推测等渔业生态学.
  相似文献   

17.
近几十年来,古代人群的食谱研究已经成为现代科技考古学的一个重要组成部分,也是当前国际科技考古学研究领域的一项前沿性课题。人类骨骼的化学元素分析为重建古代居民的食谱提供了大量信息。本文采用电感耦合等离子发射光谱仪(ICP-AES),对新疆和静县察吾呼沟口四号墓地出土人骨中的Sr、P、Zn、Ca、Cu、Mg、Fe、Ba、Mn等8种化学元素进行了测定,结果显示:察吾呼沟口四号墓地古代居民的饮食结构中以肉类食物为主,植物类食物为辅。  相似文献   

18.
中国甘肃酒泉青铜时代人类股骨化学元素含量分析   总被引:6,自引:3,他引:3  
郑晓瑛 《人类学学报》1993,12(3):241-250
  相似文献   

19.
The electrical and mechanical activities of isolated frog muscle fibres have been recorded simultaneously under conditions (chloride-free saline containing 78.5 mM strontium acetate substituting for NaCl and CaCl2) that allow the development of a tubular strontium permeability. Under voltage-clamp conditions a large part of the contraction is due to the slow inward ISr since both are inhibited by Ni (10 mM). The remaining component of contraction, which seems to be potential-dependent, is not abolished by tetracaine (40 microM) which blocks the current-dependent component. A cumulative effect of strontium, which is not observed in the presence of Ni, leads to a 60-80% reduction in contractility for an estimated [Sr]i near 3 X 10(-4) M while the ending of the contraction observed when Sr is replaced by Ba is never obtained. In contrast no cumulative effect is observed when Ca substitutes for Sr. The first evoked inward current following a caffeine contracture fails to elicit a contraction, but in Ringer 78.5 Sr, contractility is progressively restored by successive depolarizations up to an amplitude which corresponds to 25-40% of the maximum activity. In the presence of Ca instead of Sr, the restoration of contractility reaches 100%. This recovery does not occur when the inward current is blocked by Ni. After strontium loading, a calcium entry fails immediately and reversibly to induce a mechanical response while barium ions induce a progressive and irreversible block of contractility. These results suggest that the strontium entry during successive depolarizations leads to a progressive replacement of intrareticular calcium by strontium. When all the calcium ions have been substituted for by strontium ions, the contractile apparatus remains capable of being activated by intrareticular strontium.  相似文献   

20.
The contractile responses to barium and the ultrastructure and ionic composition of mitochondria were studied in vascular smooth muscle. In normal rabbit portal anterior mesenteric vein (PAMV) and main pulmonary artery (MPA) smooth muscle mitochondria were frequently associated with the surface vesicles. The average distance between the outer mitochondrial and inner surface vesicle membrane was 4–5 nm. Ba contractures of MPA were tonic and of PAMV were phasic. Incubation of MPA and PAMV with Ba resulted in the accumulation of mitochondrial granules, followed in the MPA by massive mitochondrial swelling. Oligomycin and anoxia inhibited the appearance of mitochondrial electron-opaque granules and prevented the Ba-induced mitochondrial swelling in the MPA. Electron probe analysis of mitochondria in PAMV incubated with Ba and containing granules showed characteristic Ba signals over the mitochondria. Electron probe X-ray microanalysis also showed a highly significant (P < 0.001) correlation of P with mitochondrial Ba, in an estimated elemental ratio of approximately 3 Ba/4 P. Mitochondrial granules were still prominent after block staining of the osmium-fixed, Ba-loaded PAMV, but electron probe microanalysis showed no Ba, but only U, emissions. Tissues incubated with strontium had electron-opaque mitochondrial granules and deposits in the sarcoplasmic reticulum. X-ray microanalysis of mitochondria containing granules showed the presence of characteristic Sr and Ca emissions. The presence of Sr was similarly verified in the sarcoplasmic reticulum. These findings indicate the energy dependent uptake of divalent cations, in association with phosphate, by mitochondria in vascular smooth muscle in situ and the possibility that mitochondria may contribute to the regulation of intracellular divalent cation levels in smooth muscle.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号