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481.
Three cases of scalp involvement by M. canis in infants are briefly reported. The first was a 2-month-old female with a few erythematous spots on the scalp, the second an 8-month-old male with lesions resembling seborrhoeic dermatitis and the third an 11-month-old male having areas of folliculitis of a kerion type. The father of the second case was found to have a tinea barbae infection due to the same fungus. Stray kittens were the most probable source of infection in all these cases.  相似文献   
482.
A spectrofluorimetric approach that is sensitive, simple, validated, and cost-effective has been proposed for the estimation of amlodipine (AML) and perindopril (PER) in their bulk powders, pharmaceutical formulations, and spiked human plasma. The recommended approach utilized the quantitative quenching effect of the two cited drugs on the fluorescence intensity of erythrosine B, as a result of complex binary reactions among each drug with erythrosine B at pH 3.5 (Teorell and Stenhagen buffer). The quenching of erythrosine B fluorescence was recorded at 554 nm after excitation at 527 nm. The calibration curve was detected in the range 0.25–3.0 μg ml−1, with a correlation coefficient of 0.9996 for AML, and 0.1–1.5 μg ml−1, with a correlation coefficient of 0.9996 for PER. The established spectrofluorimetric approach was validated for the estimation of the cited drugs with high sensitivity regarding International Council on Harmonization guidelines. Therefore, the established approach could be utilized for quality control of the cited drugs in their pharmaceutical formulations.  相似文献   
483.
A growing body of evidence supports the concept of helminths therapy in a variety of autoimmune diseases. Here, we aimed to investigate the protective effects of autoclaved Schistosoma mansoni antigen (ASMA) and Trichinella spiralis antigen (ATSA) on the clinical and immunopathological features of rheumatoid arthritis (RA). Adjuvant arthritis was induced by subcutaneous and intradermal injections of complete Freund’s adjuvant into the plantar surface of the right hind paw and the root of the tail, respectively. Rats were randomly assigned to serve as normal control, untreated arthritis, ASMA or ATSA-treated arthritis groups. Antigens were given by intradermal injection in two doses, two weeks apart. The development, progression of arthritic features, and the impact on animals’ gait and body weight were followed up for 4 weeks. The associated changes in serum cytokines (IL-17, IFN-γ and IL-10), joints’ histopathology and immunohistochemistry of Foxp3+ T regulatory cells (Tregs) were evaluated at the end of the study. Treatment with either ASMA or ATSA attenuated the progression of clinical features of polyarthritis, improved gait and body weight gain, reduced the elevated serum IL-17 and further increased both IFN-γ and IL-10. Histopathologically, this was associated with a remarkable regression of paws’ inflammation that was limited only to the subcutaneous tissue, and a significant increase in the number of Foxp 3+ cells versus the untreated arthritis group. In conclusion, both Schistosoma mansoni and Trichinella spiralis derived antigens exerted protective effect against adjuvant arthritis with better effect achieved by ASMA treatment. This anti-arthritic activity is attributed to upregulation of the Foxp3+ Tregs, with subsequent favorable modulation of both pro- and anti-inflammatory cytokines. The use of autoclaved parasitic antigens excludes the deleterious effects of imposing helminthic infection by using live parasites, which may pave the way to a new therapeutic modality in treating RA.  相似文献   
484.
The ECM is composed of various cell-adhesive glycoproteins, such as, fibronectin (FN), laminin (LN), and different types of glycosaminoglycans and proteoglycans. These building blocks of the ECM are linked together to form a dense and complex tissue that fills the interstitial spaces and comprises the boundaries between cells and tissues. The ECM is the major milieu in which immune cells function during inflammatory processes (Shimizu and Shaw, 1991; Yamada, 1991). Recognition of ECM-glycoproteins by immune cells is mediated by very late activation (VLA) receptors, also referred to as integrins of the β1-subfamily (Hynes, 1992). A prerequisite of lymphocyte-ECM interactions is activation of the cells by mitogens, or via their CD3-T cell receptor complex, either of these types of activation modulates the affinity of otherwise inactive β1-integrins (Shimizu, et al., 1990).  相似文献   
485.
As part of an ongoing study about the genetic determinants of shoot regeneration we tested the hypothesis that the process of shoot formation and rooting in tissue culture involves groups of genetic determinants that can be discerned from each other. We used Kniphofia lines that were part of a breeding program and were crossed to produce a F1 hybrid. We used the Kniphofia propagation protocol to study the response of the parental lines to the propagation protocol and to see if we can discern some genetic insight from the F1 cross. It was found that the response to glucose was a receive type genetic response while the response to cytokinin to auxin ratio varied and dependent on the type of auxin. But in general, the response to cytokinin to auxin ratio was dominant and additive in most cases. The response to IBA in the rooting medium was semi dominant. This is publication number 05/05 from Horticulture Institute Aro.  相似文献   
486.
487.
In this paper, the preparation, characterization and dye adsorption properties of nanocomposite (calcium alginate/organophilic montmorillonite) (CA/OMMT) were investigated. A new nanocomposite consisting of alginate and OMMT was prepared by polymerization using γ-rays irradiation as initiator. Physical characteristics of CA/OMMT were studied using X-ray diffraction (XRD), infrared spectrophotometery (IR), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED). Two textile dyes, acid green B and direct pink 3B, were used as model anionic dye. Factors affecting dye sorption, such as pH, sorbent concentration and temperature of each dye solution were extensively investigated. It was found from the study that the sorption of dyes by the nanocomposite is pH-dependent and maximum sorption was obtained at pH 2. The thermodynamic data showed that dye adsorption onto alginate was spontaneous, exothermic, and a physisorption reaction. On the basis of the data of the present investigation, one could conclude that the as-prepared adsorbents exhibited excellent affinity for the dye, and can be applied to treat wastewater containing anionic dyes.  相似文献   
488.
489.
The two histidines of the insulin monomer play a vital role in the organization of insulin into insulin hexamers. The B10 histidines bind to zinc to form two-zinc insulin hexamer, and both the B5 and B10 histidines are implicated in the formation of four-zinc insulin hexamer. These two histidines are both accessible to solvent in the dimeric form of insulin, the predominant species present at pH 2–3. In the present work we report the first 500-MHz1H NMR studies of insulin. At this frequency all four proton resonances from the two histidines of each equivalent monomer are resolved. The resonances are assigned to the C(2)- and C(4)-imidazole protons of B5 His and B10 His employing Carr-Purcell pulse sequences to detect singlets and to observe approximateT 2 relaxation times. Zinc-free bovine insulin at pH 2.9 was examined at temperatures up to 60°C in acetate buffer and in urea of varying concentrations. The environments of B5 His in molecule I and molecule II of the dimer must be the same, with the same being true for B10 His, since a total of only four sharp resonances are seen. Our assignments for the two C(2) protons are consistent with those determined from recent studies of human (B5 Ala) insulin.  相似文献   
490.
Plant Cell, Tissue and Organ Culture (PCTOC) - The significant use of copper oxide nanoparticles (CuO NPs) has generated worries over their impacts on the ecosystem and human health due to their...  相似文献   
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