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1.
Neutron activation analysis (NAA) is an appropriate tool for the determination of trace elements in biological systems. The
virtually blank-free NAA procedures fittingly complement precautions employed in sampling and sample preparation of biological
matrices. Results from instrumental NAA procedures used to establish baseline values and time trends for elements in human
tissues demonstrate the advantages as well as the limits of these procedures for nanomole and, in a considerable number of
instances, subnanomole elemental levels. In addition, subnanomole mass fractions have been determined with extremely low limits
of detection by employing NAA with radiochemical separations isolating very low levels of radioactivity from the matrix background.
The elements reviewed in this article include Cr, Se, Pt, and others that have been determined by NAA at subnanomole levels
in human tissues and body fluids and in biological macromolecules. 相似文献
2.
Vandecasteele Carlo Vanhoe Hans Dams Richard Versieck Jacques 《Biological trace element research》1990,(1):553-560
The determination of trace and ultratrace elements in human serum by ICP-MS is described. The accuracy of the method is tested
using a “second generation” human serum reference material. Elements determined include Fe, Co, Cu, Zn, Br, Rb, Sr, Mo, and
Cs. The method is compared to nuclear analytical methods (NAA, PIXE). Perspectives for the future are also discussed. 相似文献
3.
W. D. Ehmann W. R. Markesbery E. J. Kasarskis D. E. Vance S. S. Khare J. D. Hord C. M. Thompson 《Biological trace element research》1987,13(1):19-33
Although the etiology and pathogenesis of Alzheimer’s disease, Pick’s disease, and amyotrophic lateral sclerosis are still
unknown, it has been suggested that perturbations in element metabolism may play a role. Even if not causative factors, these
imbalances may prove to be markers that could aid in diagnosis. We have employed a sequential neutron activation analysis
(NAA) procedure to determine elemental concentrations in brain, hair, fingernails, blood, and cerebrospinal fluid (CSF) of
these patients and age-matched controls. Samples are first irradiated with accelerator-produced 14-MeV neutrons for determination
of nitrogen and phosphorus, then with reactor thermal neutrons for the instrumental determination of 16–18 minor and trace
elements, and, finally, reactor-irradiated again, followed by a rapid radiochemical separation procedure (RNAA) to determine
four additional elements. Major advantages of NAA are: (1) its simultaneous multielement capability; (2) the relative freedom
from reagent and laboratory contamination; (3) the absence of major matrix effects; and (4) an adequate sensitivity for most
elements of interest. Ranges of concentrations by INAA and RNAA in selected control tissues and interelement correlations
in control brain are presented to illustrate results obtained by the procedure. Longitudinal studies of tissues from Alzheimer’s
disease (AD) and amyotrophic lateral sclerosis (ALS) patients are still in progress. 相似文献
4.
Mineral and trace element interactions were studied in a balance trial with rats. Calcium, copper, and zinc were supplied
to a rapeseed meal diet in a factorial design. Animals were fedad libitum, and absorption, excretion, and retention of the elements were evaluated either as fractions of total intake or in relation
to nitrogen retention to account for differences in food intake and lean body mass increment. The intrinsic content of minerals
and trace elements was sufficient to support growth at a rate that could be expected from the rapeseed protein quality. However,
when calcium was included in the diet, the intrinsic dietary level of zinc appeared to be limiting, despite the fact that
the zinc level was twice the recommended level. Additional zinc supply reversed growth impairment. This calcium-zinc interaction
is believed to be owing to the formation of phytate complexes. Calcium addition influenced the calcium, phosphorus, magnesium,
zinc, and iron—but not the copper—balances. The addition of calcium reduced the availability of the intrinsic zinc, whereas
no effect was seen in the zinc-fortified groups. The availability of intrinsic copper was in a similar way significantly impaired
by addition of dietary zinc, where-as copper-supplied groups were unaffected by zinc addition. Intrinsic iron availability
was also dependent upon zinc addition, although in a more ambigouus way. Thus, addition of extrinsic minerals to a diet high
in phytate can result in significant impairments of growth and mineral utilization. 相似文献
5.
Claudio Tennie Kathrin Greve Heinz Gretscher Josep Call 《Primates; journal of primatology》2010,51(4):337-351
Individuals observing a proficient model can potentially benefit by copying at least one of the following three elements:
motor movements (i.e., actions), goals, and results. Although several studies have investigated this issue in human infants,
there are still very few studies that have systematically examined great apes’ ability to spontaneously copy each of these
three elements (particularly in comparison with human infants). We tested great apes and human children with eight two-target
puzzle boxes—with varying levels of difficulty—to isolate the aspects that the various species may be more prone to copying.
We found first trial evidence for observational learning of actions, goals, and results in children. Some copying was found
for apes as well, but only if their performance was averaged across trials. 相似文献
6.
Andrási E. Nádasdi J. Molnar Zs. Bezur L. Ernyei L. 《Biological trace element research》1990,(1):691-698
A study was undertaken to determine the average values for elements in normal human brain (11 individuals, age group 65–75).
Twelve brain parts were selected from both hemispheres. Determinations were carried out by NAA and ICP-AES. The main elements
(Na, K, Mg, Ca, Fe, P, S) and trace elements (Al, B, Co, Cr, Cu, Mn, Ni, Pb, Zn) were investigated. Quality control was ensured
by using NBS Bovine Liver SRM. The results obtained with independent methods were compared, and the data show a good correlation.
On the basis of these investigations, the regional distribution of elements can be given. 相似文献
7.
Josef Kiem 《Biological trace element research》1988,15(1):83-88
Blood and its main components are commonly used to detect states of selenium deficiency. In order to examine whether human
platelets are able to provide better or additional information, improvements analytical method resulted in surprisingly narrow
normal ranges for selenium and other mineral elements using neutron activation analysis (NAA) and atomic absorption spectrophotometry
(AAS), and controlling thermal neutron flux, (n,γ)-cross sections, mean platelet wet wt, and water fraction of the platelets.
Previously reported selenium concentrations in platelets on wet wt basis in the order of 500 ng/g—half of which had been found
to derive from early bone marrow precursors using74Se-selenite—were reproduced by NAA and AAS. However, with the new analytical method the selenium concentrations showed a narrower
normal range than that of plasma. Moreover, platelet selenium did not in all cases correlate with plasma selenium. Cellular
tissues such as platelets should, therefore, help to detect latent states of selenium deficiency. 相似文献
8.
Zhuang G. S. Wang Y. S. Tan M. G. Zhi M. Pan W. Q. Cheng Y. D. 《Biological trace element research》1990,26(1):729-736
In order to study the relationships between trace element concentrations of hair and internal body burdens, a radiochemical NAA technique has been used for determination of the elements As, Cd, and Hg in autopsy samples of liver, kidney-cortex, lung, and hair from 24 male persons who died by accident. High significant positive correlations were observed between the As concentration in hair and in kidney-cortex, and between Cd and Zn concentrations in kidney-cortex. The contents of Cd, both for lung and kidney-cortex, were related to the smoking habits of the subjects.
相似文献9.
Impacts of land use and water quality on macroinvertebrate communities in the Pearl River drainage basin,China 总被引:2,自引:0,他引:2
Yixin Zhang David Dudgeon Dongsheng Cheng Wai Thoe Lincoln Fok Zaoyin Wang Joseph H. W. Lee 《Hydrobiologia》2010,657(1):71-88
The East River (Dong Jiang), a major tributary of the Pearl River (Zhu Jiang, the second largest river in China by discharge),
is situated in southern China, which has the highest rates of urbanization and development on Earth. The East River also provides
80% of Hong Kong’s water supply. However, there have been no ecological studies to examine the combined impacts of changes
in land use and water quality degradation on this river ecosystem. We tested the hypothesis that land-use disturbance and
water quality degradation would significantly reduce benthic biodiversity in the East River by investigating macroinvertebrate
community composition and relating it to data on water quality and catchment condition. The percentage of total impervious
area within each catchment (%TIA—an indicator of land-use disturbance) was negatively related to a composite water quality
index—the ERWQI—we developed for the East River. Modeling by partial least squares projection to latent structures (PLS) showed
that family richness and relative abundance index (RAI) of macroinvertebrates were strongly influenced by both %TIA and ERWQI.
Multi-response permutation procedure (MRPP) tests showed highly significant differences in family richness composition and
RAI of macroinvertebrates among sites in the upper, middle, and lower course of the East River. MRPP also revealed differences
in the family richness composition of nighttime drift samples between upper and middle site groups. Abundance (individuals
m−3) and total family richness of drifting macroinvertebrates at each site were positively related to %TIA (range: 1.0–8.5%),
while drift biomass was negatively related to dissolved oxygen and positively related to total suspended solids. Thus, human
disturbances associated with land-use changes (increasing %TIA) and nutrient inputs severely degraded ecosystem integrity
and the water quality of the East River and thereby reduced aquatic biodiversity. 相似文献
10.
Feeding experiment on nine feral minkMustela vison Schreber, 1777 was carried out to find differences in digestibility of particular prey types. The values of correction factors
(CF), which show the ratio between consumed prey biomass and undigested remains, were calculated for seven food types. The
experiment revealed that results obtained by commonly used percentage of occurrence methods differed from the real intake
of food. Food types which were intensively digested were underestimated by percentage of occurrence methods and prey which
had hardly digestive elements of their body were overestimated. The calculated values of CF are as follows: crayfish — 14.8,
fish — 30.8, frog — 61.3, small passerine bird — 17.2, chicken — 41.3, rodent — 17.3, egg — 687.5. The variability in CF values
did not depend on mink individuals but could be explained by the mean weight of prey items eaten by mink. The positive correlation
between the prey size and its digestibility was recorded for crayfish, fish and chicken. The biomass of frog, passerine and
rodent remains was not related to the body mass of eaten prey. The use of evaluated correction factors enables more accurate
estimates of the food composition of wild living mustelids. 相似文献
11.
Today cardiovascular diseases (CVDs) are the killer number one world wide. In 2004 an estimated 17.1 million people died due
to CVDs and this number will further increase to an estimated 23.6 million by 2030. Importantly, currently known risk factors,
like hypertension, and hypercholesterolemia, can only be made responsible for about 50–75% of all CVDs, highlighting the urgent
need to search for and define new CVD risk factors. Cadmium (Cd) was shown to have the potential to serve as one such novel
risk factor, as it was demonstrated—in vitro, in animal studies, and in human studies—that Cd causes atherosclerosis (the
basis of most CVDs). Herein, we discuss the molecular and cellular biological effects of Cd in the cardiovascular system;
we present concepts on the pathophysiology of Cd-caused atherosclerosis, and provide data that indicate an epidemiological
relevance of Cd as a risk factor for CVDs. 相似文献
12.
For neutron activation analysis (NAA), the usual matrix problems of sodium, chlorine, and bromine are well known to give rise
to high backgrounds that inhibit the determination of several trace elements for short-lived or medium-lived NAA. For long
counting times in long-lived NAA, very low backgrounds are required to achieve good sensitivities. We have investigated the
use of thermal and epithermal NAA in conjunction with Compton suppression to determine several elements such as arsenic, antimony,
cadmium, and mercury, at the level of a few nanograms. The values of these techniques are discussed in contrast to the standard
radiochemical methods. 相似文献
13.
A. M. Kellerer 《Radiation and environmental biophysics》1996,35(2):111-115
The variance method of microdosimetric measurements and its extension, the variance-covariance method, permit the determination
of an essential parameter of radiation quality, the dose mean event size,y
d. The methods have — among other advantages — the feature that they permit measurements for smaller simulated sites than the
conventional single-event technique. It is, therefore, desirable to employ them also for the determination of further moments
of the distribution ofy. The formulae for the first three moments are here derived both for the case of constant dose rate and of fluctuating dose
rates. A second article will use the same mathematical approach to deduce formulae that remain valid even if there are slow
changes of the ratio of dose rates in the two detectors for the variance-covariance method. A third article will explore —
in terms of microdosimetric data — the applicability of the formulae. 相似文献
14.
Ersoy IH Koroglu BK Varol S Ersoy S Varol E Aylak F Tamer MN 《Biological trace element research》2011,143(2):619-624
Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum
trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including
serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium
(Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17
females, 13 males, mean age 33.53 ± 9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised
control group (21 females, ten males with a mean age 33.93 ± 7.39 years). Urine fluoride levels of chronic fluorosis patients
were significantly higher than that of control subjects as expected (1.92 ± 0.10 mg/l vs. 0.41 ± 0.09 mg/l, respectively;
P < 0.001). Serum Cu levels (89.14 ± 16.77 μg/dL vs. 102.69 ± 25.04 μg/dL, respectively, P = 0.017), serum Zn levels (77.98 ± 20.58 μg/dL vs. 94.57 ± 35.87μg/dL, respectively, P = 0.032), and serum Mg levels (1.92 ± 0.18 mg/dL vs. 2.07 ± 0.31 mg/dL, respectively, p = 0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant
differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that
chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg. 相似文献
15.
G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
16.
S. Mousavi-Yeganeh 《Biological trace element research》1987,12(1):433-433
The object of this article is to apprise physicians and chemists of nuclear analytical techniques and, in particular, of ion
beam analysis (PIXE and PIGE) for the purpose of application to the clinical diagnostic method.
The feasibility of the technique, sampling, and sample preparation for trace element analysis in biological and biomedical
samples has been described previously (1–3). Analysis data from normal human blood samples and biomedical samples by ion beam
reactions have been compared at the end.
Emphasis will be placed on the use of the analytical technique on determination of the range of trace and toxic elements in
human blood samples. 相似文献
17.
Rapid and direct determination of selenium, copper, and zinc in blood plasma by flow injection-inductively coupled plasma-mass spectrometry 总被引:1,自引:0,他引:1
A flow injection-inductively coupled plasma-mass spectrometry (FI-ICP-MS) with a simple sample preparation procedure was developed
for the determination of selenium, copper, and zinc in blood serum/plasma. A serum/plasma sample was filtered through a 0.45-μm
membrane filter and diluted with a mixture of trace elements in a standard solution (9∶1, v/v). Measurement of the reference
serum sample confirmed the accuracy of our method for selenium, copper, and zinc concentration. In the case of blood plasma
samples obtained from six healthy adult males, the selenium, copper, and zinc concentrations were similar to those of a typical
healthy male in Japan. These results suggest that the sample prepartive procedure coupled with FI-ICP-MS can be used for the
routine determination of selenium, copper, and zinc in human blood serum/plasma. 相似文献
18.
Selenium and other trace elements (Cu, Zn, Br, and Rb) were determined in very small (0.75 μL) human serum and mice whole
blood samples, by an XRF method. Accurate results of elemental concentration were obtained without the need of exact volume
measurement, because of the backscatter correction used. The XRF method is highly sensitive (M.D.L.=0.06, 0.13, 0.09, 0.07,
and 0.05 ppm for Se, Cu, Zn, Br, and Rb, respectively), rapid (counting time—100 s/sample), easy to perform and therefore
suitable for routine trace element analyses. The results obtained are in good agreement with the values reported in the literature. 相似文献
19.
Steroids present in egg yolk have been shown to vary as a resultof numerous social and environmental influences and to produceboth positive and negative phenotypic outcomes in offspring.In the present study, we examined how quality of the diet affectsplasma and yolk steroids in the green anole (Anolis carolinensis),a lizard species with genotypic sex determination. We documentedthe effects of body condition on plasma testosterone (T) andcorticosterone (CORT)—steroids with frequently opposingeffects—in breeding females and on the T and CORT contentof their eggs. We chose to manipulate body condition via dietbecause resource availability is a relevant, fluctuating variablein the environment to which females can be expected to respond.Field-collected females were housed in the laboratory and kepton either a reduced, standard, or enhanced diet (differing innutritional quality and/or quantity) for ten weeks. Althoughfemales did not differ in body condition at the beginning ofthe study, we found these diet regimes effective in producingfemales that differed in condition by the end of the study.Females on diets of enhanced quality were in better condition,produced more, but not heavier, eggs, and had higher plasmaT concentrations than did females on a standard diet or oneof reduced quality. There was also a significant positive relationshipbetween laying sequence of eggs and yolk T for females on dietsof enhanced quality, but not for the females on diets of standardor reduced quality. There were no effects of quality of dieton CORT in plasma or yolk, but yolk T and yolk CORT exhibiteda strong positive correlation irrespective of treatment. Femaleson diets of reduced quality did not differ from females on standarddiets either with respect to reproductive output or to endocrineprofiles, in spite of being in worse body condition. These resultsdemonstrate that females body condition, physiology,and reproductive output can be manipulated by quality of diet,and that changes in deposition of yolk steroids in responseto diet may be minimal. 相似文献
20.
Kieran P. McNulty 《Evolution》2010,3(3):322-332
The evolutionary history of humans comprises an important but small branch on the larger tree of ape evolution. Today’s hominoids—gibbons,
orangutans, gorillas, chimpanzees, and humans—are a meager representation of the ape diversity that characterized the Old
World from 23–5 million years ago. In this paper, I briefly review this evolutionary history focusing on features important
for understanding modern ape and human origins. As the full complexity of ape evolution is beyond this review, I characterize
major geographic, temporal, and phylogenetic groups using a few flagship taxa. Improving our knowledge of hominoid evolution
both complicates and clarifies studies of human origins. On one hand, features thought to be unique to the human lineage find
parallels in some fossil ape species, reducing their usefulness for identifying fossil humans. On the other hand, the Miocene
record of fossil apes provides an important source for generating hypotheses about the ancestral human condition; this is
particularly true given the dearth of fossils representing our closest living relatives: chimpanzees and gorillas. 相似文献