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1.
Microscopic authentication is an effective method for quality control of Chinese Materia Medica (CMM) because of its speed, convenience and low cost. However, the application of modern microscopic technique in quality evaluation of Toxic and Potent Chinese Materia Medica (T/PCMM) of animal origin is seldom reported. This gap in published knowledge is increasingly serious because confusion in T/PCMM has led to serious medical problems in China and other countries in recent years. To ensure the safe and effective use of T/PCMM, an accurate and convenient method, based on macroscopic and microscopic techniques, was developed for the authentication of animal T/PCMM. The color microscopic photos of the crude drug were acquired with the light microscope, and from these their morphological and microscopic characters were described. The present method was successfully applied in the analysis of 31 T/PCMM including 17 samples originating from plants, 3 from animals, 9 from minerals, and the remaining 2 from secreta. The macro- and microscopic characters of three animal T/PCMM, namely Mylabris (Mylabris phalerata or Mylabris cichorii), Huechys (Huechys sanguinea), and Lytta (Lytta caraganae) were conclusively determined and are here presented. The results demonstrated that it was feasible to use the present microscopic characters for the authentication of the above three animal T/PCMM.  相似文献   

2.
Toxic and potent Chinese Materia Medica (T/PCMM) has become a hot and sensitive topic as more and more people around the world are interested in the safety of herbal medicines. T/PCMM is irreplaceable in treating some diseases; but it can easily cause serious problems if confused with other herbal medicines. Accurate identification is essential to ensure their safe use, but up to now, the literature on the authentication of T/PCMM is scant. Thus, we are undertaking a study of 31 T/PCMM originating from plants, animals, minerals, and secreta. Our previous study established microscopic observation as a simple, fast, accurate, and convenient method for identifying and authenticating animal and seed T/PCMM. This study focused on the authentication of flower T/PCMM as a part of the whole study. The flower T/PCMM studies were derived from two species, Datura metel L. (Flos Daturae) and Rhododendron molle G. Don (Flos Rhododendri Mollis). Other species easily confused with these two were also examined and characterized. Using the microscope camera, normal light and polarized light microscopy, we determined the macroscopic and microscopic features of the flowers; in addition, the oil immersion lens was used to study the pollen grain characteristics. The results demonstrated that flower T/PCMM can be identified and authenticated using a light microscope equipped with an oil immersion lens. This same equipment can be easily used to characterize other herbal flower medicines. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc.  相似文献   

3.
Toxic and Potent Chinese Materia Medica (T/PCMM) are being used more and more in the treatment of various diseases. In view of their toxic side effects and to ensure their safe use, accurate and reliable authentication is indispensable. However, identifying characteristics of T/PCMM are seldom reported, even though modern microscopy can provide ample, unique identifying characteristics from cells found in transverse sections and powders. In particular, no systematic authentication studies on seed T/PCMM have been conducted. In the course of our study on 31 T/PCMM originating from plants, animals, minerals, and secreta, an accurate and convenient method, based on microscopic techniques, has been developed and reported for the authentication of animal T/PCMM. The present study deals with detailed investigations on three species of seed T/PCMM, namely Semen Hyoscyami (Hyoscyamus niger L.), Semen Euphorbiae (Euphorbia lathyris L.), and Semen Strychni (Strychnos nux-vomica L.). The macroscopic characters are here described in detail, and the microscopic characters were conclusively determined by common and polarized light microscopy. Results showed that these three T/PCMM can be easily identified by the present method even when powdered and combined. Thus, the microscopic method is applicable for authentication of the earlier three T/PCMM, and the morphological and microscopic characteristics described here are proposed as parameters to establish the authenticity of these three T/PCMM.  相似文献   

4.
PEI LIU  ZHE CHEN  XIAOQIONG MA 《Biocell》2022,46(3):737-743
Sphingosine kinase 1 (SphK1) is an important synthetase during the synthesis of sphingosine-1-phosphate (S1P) from sphingosine (Sph). Previous studies demonstrated that arsenic trioxide (As2O3) could reduce the level of S1P in human gastric cancer cell line MGC-803, indicating that As2O3 may inhibit the activity of SphK1. In this study, the effect of As2O3 on the SphK1 activation pathway was investigated. Western blot and quantitative real-time PCR analysis were used to evaluate the changes in protein and mRNA levels. The multi-dimensional mass spectrometry-based shotgun lipidomics method (MDMS-SL) was used for the quantitative detection of phosphatidylserine (PS) and phosphatidic acid (PA). The results revealed that As2O3 did not affect the protein and mRNA expression of SphK1 in the MGC-803 cells. However, As2O3 increased the levels of p-ERK1/2 and CIB1 in the SphK1 activation pathway and decreased the levels of PS and PA in the MGC-803 cells. The outcomes suggested that As2O3 may enhance the activity of SphK1 by increasing the levels of p-ERK1/2 and CIB1 and decrease the activity of SphK1 by decreasing the levels of PS and PA. It was suggested that the inhibition effect is stronger and resulting in an overall decrease in the activity of SphK1.  相似文献   

5.
Two sulfides, AsSbS4, and AsAsS4 were prepared by aqueous precipitation methods. Property studies covered lubricant characteristics, and comparisons were made with As2S3, As2S3, Sb2S3 and Sb2S3. The various compounds were examined as chemical addition agents for diester lubricating grease and organic resin solid film lubricants. Details are presented for lubricant formulation and preparation, as well as laboratory test methods. The single most significant result is the dual response of AsSbS4 to steel-steel and steel-molybdenum. Previous studies have shown that sulfur compounds as a class are preferential lubricants for molybdenum; however, a lubricating effect for steel by metallic sulfides has been essentially limited to MoS2.  相似文献   

6.
The interaction of the GaSb(001) surface with fluxes of As2, As4, and Sb4 molecules is studied using reflection high-energy electron diffraction. It is shown that As2 molecules interact with a GaSb surface predominantly by an exchange mechanism, and As4 molecules by the vacancy mechanism. It is established that for the reproducible generation of In-Sb heterointerfaces in InAs/GaSb superlattices, one needs to use a flux of As4 molecules rather than As2 molecules.  相似文献   

7.
We report the microemulsion synthesis of vanadium and chromium sulfide nanoparticles (NPs) and their biological application as nanoprobes for colocalization of membrane proteins. Spherical V2S3 and Cr2S3 NPs were prepared in reverse microemulsion droplets, as nanoreactors, obtained by the surfactant sodium bis(2‐ethylhexyl) sulfosuccinate (AOT) in nonpolar organic phase (heptane). Electron microscopic data indicated that the size distribution of the nanoparticles was uniform with an average diameter between 3 ÷ 5 nm. The prepared hydrophobic nanocrystals were transferred in aqueous phase by surface cap exchange of AOT with biotin‐dihydrolipoic ligands. This substitution allows the nanoparticles solubility in aqueous solutions and confer their bioactivity. In addition, we report the conjugation procedure between α‐Lipoic acid (LA) and biotin (abbreviated as biotin‐LA). The biotin‐LA structure was characterized by 1D and 2D NMR spectroscopy. The biotinylated vanadium and chromium sulfide nanoparticles were tested as probes for colocalization of glutamate receptors on sodium‐dodecyl‐sulfate‐digested replica prepared from rat hippocampus. The method suggests their high labeling efficiency for study of membrane biological macromolecules. Microsc. Res. Tech. 79:799–805, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

8.
Growth‐year authentication has extraordinary significance for plant growth, structure and development research, and has a wide range of applications in value assessment of economic crops. Panax ginseng is the most commonly used medicinal plant in Asian countries. The fix number of growth‐year is an important quality evaluation which is difficult to be obtained accurately in current technical conditions. Preliminary authentication theory for growth‐year has been described in previous studies using a short‐lived perennial medicinal plant (Paeonia lactiflora pall.) as the research material. In this research, we focused on the growth‐year estimation in ginseng cultivars, and attempt to explore the age estimation method for vascular plants according to mathematical simulation of the root structure development. Micro data was obtained from 204 individuals of 3 different kinds of ginseng cultivars, which have a series of gradient age and a clear growth record. Outer diameter of the vascular cambium (b) and the radius of cross section (r) were measured with ordinary stereo microscope. We further designed and established two different kinds of authentication model based on the taproot structure development for growth year authentication (P and M = K*X1a1X2a2). Moreover, the models were applied to identify the growth year of ginseng without damage using Micro‐CT or DEI reconstruction. A potential method, have been recently described, the age of ginseng can be analyzed by telomere length and telomerase activity. However, we found that there are different results indicated in other species. We concluded that microscopic methods perceived currently were provided a more effective means for growth‐year authentication. Microsc. Res. Tech. 79:98–105, 2016. © 2016 The Authors Microscopy Research and Technique Published by Wiley Periodicals, Inc.  相似文献   

9.
Thin films incorporating GaN, InGaN and AlGaN are presently arousing considerable excitement because of their suitability for UV and visible light‐emitting diodes and laser diodes. However, because of the lattice mismatch between presently used substrates and epitaxial nitride thin films, the films are of variable quality. In this paper we describe our preliminary studies of nitride thin films using electron backscattered diffraction (EBSD). We show that the EBSD technique may be used to reveal the relative orientation of an epitaxial thin film with respect to its substrate (a 90° rotation between a GaN epitaxial thin film and its sapphire substrate is observed) and to determine its tilt (a GaN thin film was found to be tilted by 13 ± 1° towards [101 0]GaN), where the tilt is due to the inclination of the sapphire substrate (cut off‐axis by 10° from (0001)sapphire towards (101 0)sapphire). We compare EBSD patterns obtained from As‐doped GaN films grown by plasma‐assisted molecular beam epitaxy (PA‐MBE) with low and high As4 flux, respectively. Higher As4 flux results in sharper, better defined patterns, this observation is consistent with the improved surface morphology observed in AFM studies. Finally, we show that more detail can be discerned in EBSD patterns from GaN thin films when samples are cooled.  相似文献   

10.
Authentication is the first priority when evaluating the quality of Chinese herbal medicines, particularly highly toxic medicines. The most commonly used authentication methods are morphological identification and microscopic identification. Unfortunately, these methods could not effectively evaluate some herbs with complex interior structures, such as root of Aconitum species with a circular conical shape and an interior structure with successive changes. Defining the part that should be selected as the standard plays an essential role in accurate microscopic identification. In this study, we first present a visual 3D model of Aconitum carmichaeli Debx. constructed obtained from microscopic analysis of serial sections. Based on this model, we concluded that the point of largest root diameter should be used as the standard for comparison and identification. The interior structure at this point is reproducible and its shape and appearance can easily be used to distinguish among species. We also report details of the interior structures of parts not shown in the 3D model, such as stone cells and cortical thickness. To demonstrate the usefulness of the results from the 3D model, we have distinguished the microscopic structures, at their largest segments, of the other three Aconitum species used for local habitat species of Caowu. This work provides the basis for resolution of some debate regarding the microstructural differences among these species. Thus, we conclude that the 3D model composed of serial sections has enabled the selection of a standard cross‐section that will enable the accurate identification of Aconitum species in Chinese medicine. Microsc. Res. Tech. 78:425–432, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

11.
To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO3) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud‐like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p < .05). The analytic results of FTIR spectroscopy showed that 95.7% (89/93) of the mud‐like gallbladder stones were CaCO3 stones, and mainly aragonite; while all of the coralliform stones were CaCO3 stones, and mainly calcite (p < .05). Meanwhile, microscopic examination indicated that the detection rate of Clonorchis sinensis eggs in mud‐like CaCO3 stones was lower than that in coralliform CaCO3 stones (p < .05), and that in aragonite CaCO3 stones was lower than that in calcite CaCO3 stones(p < .05). Mud‐like CaCO3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO3 stones. Cystic duct obstruction was mainly associated with mud‐like (aragonite) CaCO3 stones.  相似文献   

12.
The friction‐reducing and anti‐wear effect of the 500SN base oil containing diisopropyl phosphite (T451) and over‐based calcium sulphonate (KT5447) on AISI 52100 steel/Al2O3 ceramic were investigated with a ball‐on‐disc tribometer at a light load of 200 N and a high load of 400 N. The results indicate that the 500SN base oil containing T451 and KT5447 appears to have a synergistic effect on the pair. For the light load of 200 N, the effective composition is 3 wt% T451 + 2–3 wt% KT5447. For the high load of 400 N, the combination of T451 and KT5447 appears to have a synergistic friction‐reducing and anti‐wear effect. The scanning electron microscope images show that ploughed grooves, pitting, spalling and corrosion are the dominant wear modes for both 200 and 400 N. However, no evidence for the formation of the expected sulphur‐containing or phosphorus‐containing chemical compound is found according to X‐ray photoelectron spectroscopy analysis of the worn steel ball surface at both loads. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

13.
The tribological properties of two novel heterocyclic derivatives as additives in rape seed oil and in mineral oil were investigated using a four‐ball machine. The morphologies and chemical features of the worn steel surfaces were observed and examined by means of X‐ray photoelectron spectroscopy and scanning electron microscopy. Both heterocyclic compounds improved the load‐carrying and extreme‐pressure capacities and the friction‐reducing and antiwear properties of rape seed oil more than they improved those of the mineral oil. Surface analyses of the rubbed surfaces revealed the formation of a protective film containing FeSO4, organosulphur compound, FeS2, polymerised ester, and organonitrogen compound when the surfaces were lubricated by rape seed oil containing the additives. The protective film formed during sliding processes contributed to the increase in the wear resistance.  相似文献   

14.
The famous lacquer wares excavated from the Jiuliandun Tombs of the middle and late Warring States period (476–221 BC) were analyzed using scanning electron microscopy/energy as well as dispersive X‐ray spectrometry (SEM/EDS), Raman spectroscopy (RS), optical microscopy (OM), and X‐ray diffraction (XRD). The results showed a multilayer structure in the lacquer film, including a Qihui layer (a layer made of lacquer and various plasters), undercoat layer (or finishing coat) and colored paint layer mixed with various inorganic particles, such as quartz (SiO2) and hydroxyapatite [Ca5(PO4)3(OH)], as fillers in the Qihui layers or orpiment (As2S3) and cinnabar (HgS), which were used as a yellow or red pigment, respectively. With the help of elemental mapping images, a double‐layer structure of the lacquer plaster was observed, corresponding to a mixture of lacquer liquid and bone ash [Ca5(PO4)3(OH)], with large‐diameter particles in the ground lacquer layer near the wooden body and small quartz (SiO2) particles in upper lacquer layer. Specifically, quartz particles detected in the undercoat layer as fillers could be beneficial for improving the moshardness value, cost reduction and abrasive resistance of the lacquer film. In fact, the mixed method that used urushi and inorganic particles to form lacquer plaster was an important technological innovation and deeply influenced lacquering technologies worldwide. The results of this study will not only contribute to understanding the importance of lacquer skills in the Chinese Warring States but also provide information for cultural relic conservation as well as modern lacquer manufacturing for their protection and duplication.  相似文献   

15.
For some years, reports have been published on adding solid lubricant powder to oil to improve the tribological properties of the latter, but the results have not been satisfactory. In this paper, we describe the preparation of CaCO3 nanoparticles in a microemulsion consisting of sodium dodecyl‐sulphate (SDS)/isopentanol/cyclohexane/water, and assessment of the tribological behaviour of CaCO3 nanoparticles as additives for lubricating oils. The CaCO3 nanoparticles were characterised by transmission electron microscopy (TEM), and their tribological performance was tested in a four‐ball machine; the rubbing surface was analysed with X‐ray photoelectron microscopy (XPS). The results indicate that the size of CaCO3 nanoparticles increased with the concentration of aqueous reactant, and that CaCO3 nanoparticles exhibited good load‐carrying capacity, antiwear and friction‐reducing properties. The tribological properties of lubricating oils could be improved significantly by dispersing CaCO3 nanoparticles in 500SN base oil containing dispersants such as polyisobutene‐butanediimide (T154), calcium alkylsulphonate (T101) and methyl‐tricaprylamine chloride (aliquat 336). The improvements in friction and wear were concluded to be due to the formation of a film containing CaCO3 and CaO in the rubbing region, and the presence of nanoparticles, which may act in the same way as ball bearings, to facilitate sliding.  相似文献   

16.
In order to improve the tribological properties of Ni-based composites, novel adaptive Ni-based composites containing multiple lubricants were prepared via a mechanical alloying and hot-press sintering technique. The phase constituents and microstructure of the composites were characterized and the tribological properties were evaluated from room temperature to 700 °C. The results showed that the Ag2MoO4 phase decomposed and new phases of Mo2C, Ag, and MoO3 formed in the sintered composites, which can be attributed to the solid state reaction of silver molybdate lubricant during the sintering process. The wear test results indicated that the Ni-based composites containing graphite and silver molybdate lubricants exhibited superior tribological properties at ambient and high temperatures. Subsequently, the Raman results demonstrated that the composition of the tribo-layers on the worn surface of the Ni-based composites was varied with increasing temperature. Combined with the wear test results, it can be proposed that the improvement of tribological properties is due to the synergistic lubricating action of silver molybdate, iron oxide, and nickel oxide. Furthermore, Raman results of the composite containing silver molybdate and silver/molybdenum trioxide lubricants revealed that the silver molybdate lubricant can reproduce easily by the direct reaction between molybdenum trioxide and silver in the agglomerate state.  相似文献   

17.
The quantitative effects of beam current-density and sample mass-thickness on the loss of chlorine which occurs from lyophilized solutes of micro-droplets of mineral salt solutions irradiated in an electron probe analyser were studied. Results are reported for chlorine loss from lyophilized deposits with mass-thickness varying between 5 and 50 mg mm?2 for NaCl salts and 5 and 80 mg mm?2 for KCl salts. Electron accelerating voltage was kept constant at 15 kV. The range of beam current-density (I/S, current/sample surface area) was from 0.1 to 1.5 A mm?2. Samples were irradiated for 1200 s. The results show that under some conditions there is a period of stable chlorine signal before chlorine loss occurs. This is observed between 0.1 and 1 A mm?2, for a period which can last several hundred seconds depending on beam current-density and sample mass-thickness. For each value of I/S, however, no stable chlorine signal can be observed for samples whose mass-thickness exceeds a value negatively correlated with I/S. The curves of decrease of characteristic chlorine X-ray signal (expressed as per cent of count rate in the initial counting interval) versus irradiation time can be fitted by the sum of two exponentials with half lives T1 and T2. In NaCl, T1 and T2 values are highly correlated with I/S but not with mass-thickness. In KCl, T1 is correlated only with mass-thickness and T2 only with I/S. Mixing plasma with mineral solutions prevents chlorine loss.  相似文献   

18.
Surface density (SV) and length density (LV) of myocardial capillaries have hitherto been estimated from their profile boundary length (BA) and their numerical density (QA) on transverse sections by the simplifying assumptions of the Krogh model (perfectly anisotropic, straight, unbranched capillaries with constant cross-sectional area). As the capillaries actually are partially anisotropic, curved, branching cylinders with variable cross-sectional area, a geometrical bias arises from the model-reality discrepancies. We have applied and compared two methods to overcome these inconsistencies: (1) estimation of LV and SV by a more realistic model (the Dimroth-Watson distribution); (2) estimation of LV and SV from isotropic uniform random (IUR) sections. Twelve male Wistar rats were fixed by retrograde vascular perfusion. One pair of longitudinal and transverse sections, and six IUR sections per animal were selected at random from the left ventricular papillary muscles. Ultrathin sections were silver-impregnated and studied by light microscopic morphometry. Nearly identical estimates of LV and SV were found by both methods. The model-based estimation provides biologically meaningful anisotropy constants, but it presupposes knowledge of the anisotropy axis. The IUR method provides no measure of anisotropy, but it can be applied in tissues where the anisotropy axis is not known. Both methods are equally efficient and practically unbiased in SV estimation, but the model-based estimation is far more efficient in LV estimation.  相似文献   

19.
Swertia cordata (G. Don) C.B. Clarke is one of the potential medicinal plants extensively used in eastern traditional medicine such as Unani, Ayurveda, Siddha, and in traditional Tibetan and Chinese medicine. S. paniculata is the common adulterant of S. cordata at herbal shops and markets but S. paniculata is also used in number of herbal formulations. The present study was conducted to use microscopic, pharmacognostic, and phytochemical techniques as a tool for the authentication of herbal drug chiraita (S. cordata). In herbal markets, mixing, adulteration, and use of spurious materials as substitute have become a major concern for herbal practitioners, local user, and industry for reasons of safety and efficacy. Therefore, authentication of medicinal plants is of utmost importance at each level of drug research. In the present study, anatomical features of two species showed a great diversity, as irregular epidermal cells and nonglandular, unicellular trichomes were found in S. cordata while in S. paniculata epidermal cells were hexagonal in shape and trichomes were A‐shaped. Antioxidant activity of two species showed a great variation where IC50 value recorded for S. cordata was 208 μg/mL, while for S. paniculata IC50 was 624 μg/mL. The study can serve as an important source of information to achieve the authenticity and to evaluate the quality and purity of the plant material in accordance to WHO guidelines. As this species is greatly exploited, so conservation is highly recommended.  相似文献   

20.
Ettringite, Ca6Al2(SO4)3(OH)12.26H2O, or C6A3H32 as it is known in cement chemistry notation, is a major phase of interest in cement science as an hydration product and in polluted soil treatment since its structure can accommodate with many hazardous cations. Beyond those anthropogenic features, ettringite is first of all a naturally occurring mineral (although rare). An example of its behaviour under the scanning electron microscope and during energy dispersive spectroscopy (EDS) qualitative analysis is presented, based on the study of natural ettringite crystals from the N'Chwaning mine in South Africa. Monte Carlo modelling of the electron‐matter interaction zone at various voltages is presented and confronted with actual, observed beam damage on crystals, which burst at the analysis spot. Finally, theoretical energy dispersive spectroscopy spectra for all the ettringite group minerals have been computed as well as Monte Carlo modelling of the electron‐matter interaction zone. The knowledge of the estimation of the size of this zone may thus be helpful for the understanding of energy dispersive spectroscopy analysis in cement pastes or ettringite‐remediated soils.  相似文献   

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