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71.
Anti-neutrophil cytoplasmic antibodies (ANCA) are the immunodiagnostic markers for idiopathic necrotizing crescentic glomerulonephritis affecting mainly medium to small sized blood vessels. The diagnosis of ANCA associated vasculitis (AAV) is mainly based on clinical and histopathological characteristics along with the serological evidence. Immunofluorescence microscopy (IIF) is considered as the "gold standard" for ANCA detection, and ANCA showing two major patterns ie, cytoplasmic (c-ANCA) and perinuclear (p-ANCA) react with different antigenic targets of neutrophils like Proteinase3 (PR3) and Myeloperoxidase (MPO). A third unusual and rare immunofluorescence pattern called as "X- ANCA" or atypical ANCA is also sometimes seen. The difficulty in identification of ANCA immunofluorescence patterns is mainly seen due to the rare dual patterns seen in the same sera and also the additional nuclear immunofluorescence seen due to presence of anti-nuclear antibodies. ANCA testing by immunofluorescence and Confocal Laser scanning microscopy, as well as by specific ELISAs for detection of anti-PR3 and anti-MPO antibodies have helped in improving the diagnosis. Patients having dual specificities to MPO and PR3 in a patient is a rare finding. Among 425 clinically and histopathologically proven cases of AAV, eight patients (1.9%) had dual specificities, of which five patients showed mixed immunofluorescence pattern and 3 patients showed X-ANCA pattern which was confirmed by both immunofluorescence and Confocal Laser scanning microscopy and the dual specificities to MPO and PR3 were detected by individual ELISAs.  相似文献   
72.
Polycrystalline Cd1?xZnxS films are prepared by the spray pyrolysis technique on amorphous substrate, at different substrate temperatures. The dark conductivity and thermoelectric power are measured and applied to calculate the electron density and mobility. The electron density decreases with increase in substrate temperature. However, mobility is higher for the films prepared at 400°C substrate temperature. The variation of electron density and mobility with substrate temperature is explained in terms of crystallanity of the film and chlorine concentration in the films. The optical absorption of the films are studied and revealed that there is not much change in band gap with substrate temperature.  相似文献   
73.
The emission spectra of calcium sulphide phosphors activated with bismuth, thulium, and both together are studied in the spectral range of 4000 Å to 8000 Å. The results indicate resonance transfer of excitation energy from Bi to Tm. Sensitizer to sensitizer transfer also appears to be appreciable. A plausible energy level diagram is proposed to explain the sensitization mechanism.  相似文献   
74.
A series of novel pyranochromene chalcones and corresponding flavanones were synthesized. This is the first report on the confirmation of the absolute configuration of chromene‐based flavanones using X‐ray crystallography. These compounds were characterized by 2D NMR spectroscopy, and their assignments are reported herein. The 3D structure of the chalcone 3b and flavanone 4g was determined by X‐ray crystallography, and the structure of the flavanone was confirmed to be in the S configuration at C‐2. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
75.
76.
JPC – Journal of Planar Chromatography – Modern TLC - In the present investigation, a simple and effective high-performance thin-layer chromatography (HPTLC) method was developed and...  相似文献   
77.
The present article describes the synthesis and characterization of tetracoordinated boron (III) complexes with monobasic bidentate ligands (L 1 H, L 2 H, L 3 H, L 4 H, L 5 H, and L 6 H) having the general formulae PhB(L)(OH) and PhB(L) 2 . The 1:1 and 1:2 reactions of phenyl boronic acid with monobasic bidentate ligands resulted in the formation of colored solids. The complexes have been characterized by elemental analysis, molecular weight determinations, and IR and NMR ( 1 H, 13 C and 11 B) spectroscopy, as well as UV-vis spectral studies. Based on these studies, a tetrahedral geometry has been proposed for the resulting complexes. The ligands, along with their complexes, have been screened in vitro against a number of pathogenic fungal and bacterial strains. The studies indicate that the boron chelates are more potent than the parent ligands.  相似文献   
78.
Dietary supplements containing dried roots or extracts of the roots and/or rhizomes of blue cohosh (Caulophyllum thalictroides) are widely available. This botanical has a long history of use by Native Americans and its use continues to the present day. The primary constituents of blue cohosh are its alkaloids and saponins. The structures of the alkaloids magnoflorine, baptifoline, anagyrine, and N-methylcytisine have been known for many years. The last 10 years have seen a great increase in isolation and identification of the large number of saponins present in blue cohosh. Important developments in nuclear magnetic resonance techniques have contributed substantially to the increase in elucidation of the structures of the complex saponins. Several authors have described quantitative methods for both the alkaloids and saponins in blue cohosh. Such methods have made it possible to quantify these constituents in dietary supplements containing this botanical ingredient. Concentrations of both alkaloids and saponins vary substantially in dietary supplements of blue cohosh. The nicotinic alkaloid, N-methylcytisine, a potent toxicant, has been found in all dietary supplements of blue cohosh analyzed. The teratogenic alkaloid anagyrine has been found in some but not all dietary supplements.  相似文献   
79.
In addition to their widely recognized use as dietary supplement ingredients, plant-derived compounds are increasingly used as natural sweeteners. The search for nonnutritive sweeteners has been stimulated over the last 20–30 years by concern over demonstrated or suspected relationships between consumption of sucrose and high-fructose corn syrups and a variety of health-related conditions. In the USA, there is increased use of plant extracts known to contain highly sweet terpenoids. Purified extracts of Stevia rebaudiana (Bertoni) containing the diterpene glycosides stevioside and rebaudioside A are popular as sweeteners and are also used as dietary supplements, and soft drinks and nutritional and energy shakes incorporating extracts of Siraitia grosvenorii (Swingle) fruits containing sweet triterpene glycosides such as mogroside V are also on the market. Here, we review recent studies on these two important sources of noncaloric natural sweeteners, including analytical methods used to identify and quantify specific constituents and structural features relating to their sweetness. We also review the generally recognized as safe status of specific components and their status with respect to review by the Joint FAO/WHO Expert Committee on Food Additives.  相似文献   
80.
The paper discuses synthesis of Ba0.7Sr0.3TiO3/La0.67Sr0.33MnO3 and Ba0.8Sr0.2TiO3/La0.67Sr0.33MnO3 thin film heterostructures by sol–gel (citrate gel route) method. The XRD spectra are determined for confirmation of crystalline phases of Ba0.7Sr0.3TiO3, Ba0.8Sr0.2TiO3 and La0.67Sr0.33MnO3 thin films. The observed variation of Cp, tan δ, magnetocapacitance (Mc), real part of dielectric constant ε′, imaginary part of dielectric constant ε″as a function of frequency, magnetoresistance R(H) and magnetoimpedance Z(H) are presented in the paper. Further the observed impedance spectra as a function of frequency f is also presented in the paper. The observed variation of Mc is qualitatively correlated with the stress induced effect and magnetoresistasnce effect occurring simultaneously.  相似文献   
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