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W. J. Altaf O. A. Akanle L. L. Admans D. Beasley C. Butler N. M. Spyrou 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):493-498
The elemental composition of human hair obtained from different studies at Surrey University over a period of 25 years has
been recorded and forms part of a database, for biological and environmental samples, which is being developed. Instrumental
neutron activation analysis (INAA), using reactor neutrons, was the principal method employed and from which reported data
are presented.Elemental concentrations of Br, Ca, Ce, Cl, Co, Cr, Cs, F, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se, V and Zn were obtained and
recorded in the database. Chronological variations in two sets of subjects separated by a period of time of 16 years are also
given. Variations in the concentration values of some elements related to the state of health and disease were reported for
hair samples collected from subjects suffering from manic depression, senile dementia and breast cancer. Concentration values
of some elements with relation to the nationality of subjects from Bulgaria, England, Kenya, Nigeria and Wales are presented
and compared. This study is part of on-going research in the analysis of biomedical and bioenvironmental materials. The database
is still in its infancy.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
Global spatial distributions of nitrogen and carbon stable isotope ratios of modern human hair 下载免费PDF全文
Frank Hülsemann Christine Lehn Sabine Schneiders Glen Jackson Sarah Hill Andreas Rossmann Nicole Scheid Philip J. H. Dunn Ulrich Flenker Wilhelm Schänzer 《Rapid communications in mass spectrometry : RCM》2015,29(22):2111-2121
4.
Photo yellowing of human hair 总被引:1,自引:0,他引:1
Nogueira AC Richena M Dicelio LE Joekes I 《Journal of photochemistry and photobiology. B, Biology》2007,88(2-3):119-125
In general, human hair is claimed to turn yellower after sun exposure. This is particularly affirmed for white hair. However, quantitative data relating yellowness to hair type and to the radiation wavelength are missing. This work shows results of the effect of full or UVB-filtered radiation of a mercury vapor or a xenon-arc lamp on the yellowness of virgin white, dark-brown, blond and red hair. All hair types showed a substantial change in yellowness after irradiation, which is dependent on the hair type and radiation wavelength. Surprisingly, white hair turns less yellow after both full and UVB-filtered radiation exposure. This effect is more pronounced when UVB is filtered from the radiation system. The only radiation that shows a photo-yellowing effect on white hair is infrared. As the yellowness of white hair is commonly related to tryptophan degradation, fluorescence experiments with hair solutions were performed to identify the natural degradation of tryptophan which occurs in hair after light irradiation. Pigmented hairs were also studied, as well as hair treated with a bleaching solution. Although we observe a decrease in tryptophan content of hair after lamp radiation, a direct correlation with hair yellowness was not achieved. Results are discussed in terms of hair type, composition and melanin content. 相似文献
5.
Phospholipids of human hair lipids 总被引:1,自引:0,他引:1
6.
A. Gordus 《Journal of Radioanalytical and Nuclear Chemistry》1973,15(1):229-243
Both present-day and historical head-hair samples up to 300 years old are being analysed by neutron activation for more than
30 trace elements. This study, designed to determine an historical base-line for the human intake of trace metals and to provide
an evaluation of the present-day rate of increase and sources of environmental pollution, has direct forensic applicability.
Modern samples being analysed in this study include hair from U. S. Naval Academy midshipmen and U.S. Air Force Academy cadets
obtained upon arrival at the Academies in mid-1971 and again at later intervals during which trace-metal equilibration due
to fixed diets and environmental conditions is presumed to occur. A wide variety of factors such as age, sex, hair structure
and color, geographic location, general diet, socieconomic status are being considered in evaluating the analysis data. Examples
of some of the initial data obtained from the analysis of the first three sets of Naval Academy midshipmen hair are presented. 相似文献
7.
The possibility of determination of microgram quantities of palladium by radiochemical displacement of labelled Zn from Zn: 1-/2-pyridylazo/-2-naphthol comples has been explored. Conditions for quantitative displacement, a calibration in the range of 40–140 g of palladium and the effects of diverse ions have been reported. 相似文献
8.
Chromone derivatives bearing a quaternary ammonium functionality which bind to human hair were synthesised. The radical scavenging activity, according to the DPPH assay, of the chromone derivatives is considerably lower compared with flavonoids. The compounds show interesting UV absorption properties that depend on the position of a methoxy substituent. A bathochromic shift of 29 nm was observed when the methoxy group on the ammonium salts were shifted from position 7 to position 6. 相似文献
9.
A. V. Bogdanov I. N. Glazkov T. V. Polenova I. V. Marutsenko I. A. Revel’skii 《Journal of Analytical Chemistry》2006,61(10):936-951
Data reported in the literature on methods for the determination of organic compounds of different classes in human hair are systematized. Special attention is given to methods for the extraction and preconcentration of organic compounds from hair. A comparative analysis of existing methods is performed. 相似文献
10.
Interest in hair analysis as an alternative or complementary approach to urinalysis for drug abuse detection has grown in recent years. Hair analysis can be particularly advantageous for drugs such as amphetamine and methamphetamine that are rapidly excreted. Confirmation of abuse of these stimulants is complicated by the fact that some forms are found in legitimate medications. Examination of the enantiomeric composition of amphetamine and methamphetamine in hair samples can provide valuable assistance in interpreting drug testing results. In this work, we developed a liquid chromatographic method for the separation of amphetamine and methamphetamine enantiomers isolated from human hair samples. The drug enantiomers were separated on a chiral stationary phase after derivatization with an achiral fluorescent agent. The methodology was evaluated with a Standard Reference Material that contained several drugs of abuse including amphetamine and methamphetamine.Contribution of the National Institute of Standards and Technology. Not subject to copyright. 相似文献
11.
The feasibility is explored of classifying human hair specimens according to their trace metal composition as determined by
PIXE. Protons of 3.5 MeV were used to analyse 150 samples by energy-dispersive spectrometry using a Si(Li) detector. The methods
of the Minimal Spanning Tree and Non-Linear Mapping were used to establish correlation among the specimens. As a result of
distinct groupings obtained by these methods it was inferred that these techniques could usefully be applied to environmental
pollution studies. 相似文献
12.
Petzke KJ Feist T Fleig WE Metges CC 《Rapid communications in mass spectrometry : RCM》2006,20(19):2973-2978
The stable-isotopic composition of nitrogen (delta15N) or carbon (delta13C) of body tissues depends on the isotopic composition of food sources and on shifts due to isotopic fractionation during metabolism. As little is known about the effects of pathophysiological conditions we measured delta15N and delta13C values in hair and hair amino acids of patients with cirrhosis (n = 21) and compared the results with those of healthy subjects (n = 100) randomly selected from the 1987-1988 VERA German nutrition survey population. Cirrhosis was reflected in lower hair 15N abundances (6.7 vs. 9.9 per thousand delta15N; P < 0.001) whereas hair 13C abundances did not differ from healthy subjects (-19.4 vs. -19.6 per thousand 13C). Distinct patterns of delta15N and delta13C values were measured in hair amino acids. The delta15N values of phenylalanine were significantly higher in cirrhotics (P < 0.001). With the exception of isoleucine, threonine, and proline all other measured amino acids showed lower delta15N values than healthy subjects (P < 0.001). Lower hair delta15N values were associated with cirrhotic liver disease which suggests that under this condition the altered liver amino acid metabolism affects the nitrogen isotopic composition of the amino acids used for hair protein synthesis. It remains to be determined in controlled studies whether the altered nitrogen isotopic composition directly reflects the pathophysiological condition or is related to differences in dietary protein intake from plant or animal food sources. 相似文献
13.
Andreas Pfau Peter Hssel Sabine Vogt Ralf Sander Wolfgang Schrepp 《Macromolecular Symposia》1998,126(1):241-252
We present a combination of electrochemical methods, i.e. polyelectrolyte titration and streaming potential measurement, and AFM to characterise the adsorption and desorption behaviour and the morphology of a set of polyquaternium polymers on human hair. Specific charge density and molar mass are correlated to the amount of adsorbed polymer and the ease of desorption. Results are in line with a simple model of coulombic interaction between hair and polymer and are interpreted on this basis. 相似文献
14.
Wietecha-Posłuszny R Garbacik A Woźniakiewicz M Kościelniak P 《Analytical and bioanalytical chemistry》2011,399(9):3233-3240
The objective of this research was to develop, optimize, and validate a modern, rapid method of preparation of human hair
samples, using microwave irradiation, for analysis of eight tricyclic antidepressants (TCADs): nordoxepin, nortriptyline,
imipramine, amitriptyline, doxepin, desipramine, clomipramine, and norclomipramine. It was based on simultaneous alkaline
hair microwave-assisted hydrolysis and microwave-assisted extraction (MAH–MAE). Extracts were analyzed by high-performance
liquid chromatography with diode-array detection (HPLC–DAD). A mixture of n-hexane and isoamyl alcohol (99:1, v/v) was used as extraction solvent and the process was performed at 60°C. Application of 1.0 mol L−1 NaOH and microwave irradiation for 40 min were found to be optimum for hair samples. Limits of detection ranged from 0.3
to 1.2 μg g−1 and LOQ from 0.9 to 4.0 μg g−1 for the different drugs. This enabled us to quantify them in hair samples within average therapeutic concentration ranges. 相似文献
15.
The solar erythemal UV irradiances through human hair and the protection from UV provided by human head hair have been investigated for a solar zenith angle (SZA) range of 17–51° for the conditions of a head upright in full sun, a head upright in shade and a head in full sun tilted toward the sun. The two hair lengths investigated were 49.1 ± 7.1 mm for the short type and 109.5 ± 5.5 mm for the long type. For the head upright in full sun, the irradiances through the hair ranged from 0.75 to 1.4 SED h−1 for SZA <25° and <0.6 SED h−1 in shade. The ultraviolet protection factor (UPF) ranged from approximately 5 to 17 in full sun, with the UPF increasing with higher SZA. The longer hair provided a lower UPF than the shorter hair and for the head oriented toward the sun, there was a marginally lower UPF than for the upright head. This research shows that the UV exposure limits to the scalp through hair can be exceeded within short timeframes and provides important information to assist employers to comply with Workplace Health and Safety legislation. 相似文献
16.
Binding isotherms of two types of ionic surfactants, CmH2m +1SO4Na (m = 8,10,12) and CnH2n + 1N+(CH3)3C1 (n=10, 12), to human hair in aqueous solutions were examined to clarify effects of hydrophobic and electrostatic interaction of ionic surfactants with hair. The binding isotherms of anionic surfactants showed cooperativity with discontinuously increasing shapes, while the binding isotherms of cationic surfactants showed a Langmuir-type, regardless of the difference of a hair condition.The calculated free energy change (— G@#@) for binding, obtained from Klotz' plots, suggests that the binding processes are governed mainly by a hydrophobic interaction, and bound surfactants probably expose their alkyl chains to the aqueous phase, since no-G was observed with the increase of m or n and values of enthalpy change(H) were positive or zero. 相似文献
17.
张丹 《中国无机分析化学》2014,4(3):19-25
人体无机元素含量在头发中较其它体液或组织中高,易于检出。头发能够存储较长的时间信息,并且能提供其空间信息。通过分析其中的无机元素含量和同位素比例,可以说明元素在体内特定时间的变化以及反映人体的地理位置迁移。综述了头发中无机元素分析的前处理和仪器分析方法,重点介绍头发中无机元素分析在环境、医学及法医学研究中的应用,并对未来的技术发展和应用进行展望。 相似文献
18.
Sadaie M Nishikawa N Ohnishi S Tamada K Yase K Hara M 《Colloids and surfaces. B, Biointerfaces》2006,51(2):120-129
We employed a cantilever modified with a self-assembled monolayer (SAM) as a “hair-model-probe” for friction force microscopy (FFM) to measure friction acting between hair and hair-like surfaces. The “hair-model-probe” was prepared by forming a SAM of octadecanethiol on a gold-coated cantilever. We investigated frictional properties of human hair at both root and tip, and the dependency on applied load, influence of scanning direction, and local frictional distribution. The friction coefficient of the hair tip was greater than that of the hair root. Load dependency of friction at the hair tip was clearly observed, while friction at the hair root was less dependent on applied load. At the hair root, an anisotropic frictional property was observed: friction force along the long axis of the hair fiber was about 1.5–2 times larger than that along the short axis. Atomic force microscopy (AFM) images showed striations on the cuticle cells that have about 6 nm depth and their long axis oriented in the direction of the hair fiber. The frictional distribution images revealed that the local areas showing strong shear corresponded to striations. Since such distribution of friction was not observed at the hair tip, it is suggested that the anisotropic frictional property at the hair root was caused mainly by the striations. The frictional distribution in regions that excluded the striations also showed the anisotropic frictional property that friction parallel to the long axis of the hair fiber is greater than that along the short axis. This result suggests that the orientation of fatty acid molecules comprising the fat layer (F-layer) may also contribute to the anisotropic frictional property. We have concluded that loss of the F-layer is a dominant cause of strong friction detected at the hair tip, and at the striations of the hair root. 相似文献
19.
O. A. Akanle J. Ho K. Muhiddin L. Admans N. M. Croft N. M. Spyrou 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(2):355-360
A dual energy X-ray absorptiometry (DEXA) system has been employed to measure the bone mineral density (BMD) of children with
inflammatory bowel disease (IBD); Crohn's disease (CD) and ulcerative colitis (UC) at diagnosis. The results of the study
indicate that even at diagnosis, a significantly reduced bone mineral density measured in terms of the Z-score, was observed in the lumbar spine and whole body of the IBD subjects. This was found to be more pronounced in Crohn's
disease than in the ulcerative colitis subjects. Furthermore, the study was extended to investigate the elemental composition
of hair of IBD subjects and age matched controls using instrumental neutron activation analysis (INAA). The concentrations
of 11 elements; Al, Br, Ca, Cl, Cu, I, K, Mg, Mn, Na and V were determined. A significantly reduced concentration of Ca, Cu,
K, Mn, and V were observed in the hair of IBD subjects as compared to the control group.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
Dupres V Langevin D Guenoun P Checco A Luengo G Leroy F 《Journal of colloid and interface science》2007,306(1):34-40
The electrostatic properties and the wetting behaviour of the human hair surface at the nanometric scale have been investigated by using atomic force microscopy (AFM). Surface potential imaging was used to determine the electrostatic properties while non-contact mode AFM was used to investigate the wetting properties of a test liquid, squalane. We have studied natural hair and hair in which different covalently (18-methyleicosanoic acid) and non-covalently bound fatty acids present at the cuticle surface were selectively extracted. This study shows how the removal of these acids causes various profound changes in hair wettability at the cuticle scale. 相似文献