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1.
El-Hadi Ibrahim Adil Denizli Sema Bekta
mer Gen Erhan Pi
kin 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,720(1-2):217-224
Poly(2-hydroxyethylmethacrylate–ethyleneglycoldimethacrylate) [poly(HEMA–EGDMA)] microspheres carrying Cibacron Blue F3GA and/or thionein were prepared and used for the removal of cadmium ions Cd(II) from human plasma. The poly(HEMA–EGDMA) microspheres, in the size range of 150–200 μm in diameter, were produced by a modified suspension copolymerization of HEMA and EGDMA. The reactive triazinyl dye-ligand Cibacron Blue F3GA was then covalently incorporated into the microspheres. The maximum dye incorporation was 16.5 μmol/g. Then, thionein was bound onto the Cibacron Blue F3GA-incorporated microspheres under different conditions. The maximum amount of thionein bound was 14.3 mg/g. The maximum amounts of Cd(II) ions removed from human plasma by poly(HEMA–EGDMA)–Cibacron Blue F3GA and poly(HEMA–EGDMA)–Cibacron Blue F3GA–thionein were of 17.5 mg/g and 38.0 mg/g, respectively. Cd(II) ions could be repeatedly adsorbed and desorbed with both types of microspheres without significant loss in their adsorption capacity. 相似文献
2.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species. 相似文献
3.
The authors study by means of immunoperoxidase method the pattern of thyroglobulin, triiodothyronine and thyroxine distribution in 58 cases of thyroid disorders: 15 euthyroid goiters, 10 Graves' disease, 7 Hashimoto's thyroiditis, 11 folliculo-papillary carcinomas (6 primary tumors and 5 lymph node metastases), 8 follicular carcinomas, 4 anaplastic carcinomas and 3 medullary carcinomas. Thyroglobulin, triiodothyronine and thyroxine were present in most of the thyroid disorders, excepting anaplastic and medullary carcinomas. Thyroglobulin and thyroxine were localized both in the follicular epithelium and in the colloid, whereas triiodothyronine was present especially in the follicular cells. The thyroid hormones distribution in benign lesions is rather similar. In carcinomas, the pattern of thyroglobulin, triiodothyronine and thyroxine is more heterogeneous, but generally the triiodothyronine distribution is similar to that of thyroglobulin. In some carcinomas, triiodothyronine and thyroxine showed a weak or negative immunostaining. The immunoperoxidase method is a valuable tool in the study of functional disturbances in the thyroid pathology and in the diagnosis of thyroid carcinoma metastases as well. Positive thyroid hormones staining clearly indicates the thyroid origin of metastases. 相似文献
4.
The effect of long-term (77 day) exposure of carp Cyprinus carpio to low concentrations of waterborne iron (1 mg Fe-dextran l−1 ) on accumulation and cellular distribution of iron in the liver was assessed using Perl's staining and histological observations and morphometric measurements. Accumulation of iron in the liver occurred after 14 days of exposure, when the majority of the iron was found in the sinusoidal endothelium with lower amounts in the cytoplasm and nuclei of hepatocytes. Upon further treatment the iron was predominantly distributed in the cytoplasm of the hepatocytes either as granules or diffusive iron and in macrophages. 相似文献
5.
Mehmet Yaar can 《American journal of physical anthropology》1989,78(1):3-8
This study analyzes and compares the dental size variation and sexual dimorphism of the Highland Beach Mound people, a late southeastern prehistoric aboriginal Florida population (ca. 800-1200 AD) with a somewhat earlier midwestern group (ca. 200-800 AD) and an Archaic sample (ca. 4160-2558 BC). The lengths and breadths of maxillary and mandibular permanent teeth of 99 individuals were measured, and crown surface areas were calculated for the molars. Results indicated that there was little sexual dimorphism. Only the mesiodistal dimensions of the upper P2 and lower C were significantly different at the P less than 0.05 level. In terms of dental size, what appears to be a chronologically based reduction in most points of comparison was seen in all three groups, with the exception of the molars, which were larger in the Highland Beach sample than in the earlier Schultz Mound. 相似文献
6.
The nature of neurone response of substance nigra (SN) to nociceptive stimulation of the cat's peroneal nerve has been studied. The recording of neurone SN firing rate revealed that the majority (71.0%) of the SN neurones responded to the nociceptive repetitive stimulation of the peroneal nerve. But the thresholds of nociceptive activation in SN neurones turned to be very high. As a result of it the number of SN neurones responding to repetitive peroneal stimulation was twice as many as the number of cells responding to single stimulation of the nerve. The intravenous injection of naloxone in dose 1.0 mg/kg changed both excitatory and inhibitory responses in majority (71.4%) of SN neurones responding to repetitive peroneal stimulation. Naloxone did not modify the firing rate of neurones nonresponsive to nociception. 相似文献
7.
A new dihydroflavonol, pallasiin, together with kaempferol, quercetin, isorhamnetin, mearnsetin, aromadendrin, eriodictyol and taxifolin, has been isolated from the bark of Rhamnus pallasii and its structure elucidated as 2,3-dihydromyricetin 4′-O-methyl ether. 相似文献
8.
I. Alteraş M. D. 《Mycopathologia》1966,28(4):361-367
Summary
Trichophyton quinckeanum was isolated from a spontaneous infection in rabbit. The hairs were also invaded by the fungus, exibiting a yellowish fluorescence in Wood's light. White mice inoculation of the isolate produced typical scutula with hair penetration fluorescing in green colour. The type of animal hair invasion is also discussed. The morphologic features ofTr. quinckeanum, together with its ability of producing scutula while inoculating the white mice, must be emphasized, when proving its separate identity. 相似文献
9.
The enzyme 3-methylaspartate ammonia-lyase (EC 4.3.1.2) catalyzes the exchange of the C-3 hydrogen of the substrate, (2S,3S)-3-methylaspartic acid, with solvent hydrogen. The mechanism of the exchange reaction was probed using (2S,3S)-3-methylaspartic acid and its C-3-deuteriated isotopomer. Incubations conducted in tritiated water allowed the rate of protium or deuterium wash-out from the substrates to be measured as tritium wash-in. The primary deuterium isotope effects for the exchange under essentially Vmax conditions ( [S] much greater than Km) were 1.6, 1.5, and 1.5 at pH 9.0, 7.6, and 6.5. The deamination reaction, measured spectrophotometrically on the same incubations, showed isotope effects of 1.7, 1.6, and 1.4 at pH 9.0, 7.6, and 6.5, in agreement with the values of DV and D(V/K) reported previously [Botting, N.P., Akhtar, M., Cohen, M.A., & Gani, D. (1988) Biochemistry 27, 2956-2959]. The ratio of the rate of exchange to the rate of deamination, however, varied widely with pH. Together with the identical values of the primary isotope effects for the two reactions, this result indicates that the partition between reaction pathways occurs after the slowest steps in the common part of the reaction coordinate pathway, almost certainly after the cleavage of the C-N bond at the level of the enzyme-ammonia-mesaconic acid complex, and not at the putative carbanion level as was previously suggested. The enzyme requires both K+ and Mg2+ ions for activity, although ammonium ion is also able to bind in the K+ site and act as an activator. Variation of the metal ion concentration alters the magnitude of the primary deuterium isotope effects. The variation of potassium ion concentration causes the most marked changes: at 1.6 mM K+, DV and D(V/K) are 1.7, whereas at 50 mM K+, DV and D(V/K) are reduced to 1.0. The isotope effects are also reduced at low K+ concentration due to the emergence of a slow-acting high K+ affinity monopotassium form of the enzyme. The binding order and role of the metal ion cofactors and their influence in determining the formal mechanism of the reaction is discussed, and the failure of previous workers to observe primary deuterium isotope effects for the deamination process is explained. The product desorption order was tested by product inhibition, alternative product inhibition, and isotope exchange experiments. Ammonia and mesaconic acid debind in a random fashion.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
10.
H. Yasemin Yenilmez Nazli Farajzadeh Nilgün Güler Kuşçulu Dilek Bahar Sadin Özdemir Gülşah Tollu Mithat Güllü Zehra Altuntaş Bayır 《化学与生物多样性》2023,20(4):e202201167
In this study, three new axially disubstituted silicon phthalocyanines ( SiPc1–3 ) and their quaternized phthalocyanine derivatives ( QSiPc1–3 ) were prepared and characterized. The biological properties (antioxidant, antimicrobial, antibiofilm, and microbial cell viability activities) of the water-soluble silicon phthalocyanines were examined, as well. A 1 % DMSO diluted with pure water was used as a solvent in biological activity studies. All the compounds exhibited high antioxidant activity. They displayed efficient antimicrobial and antimicrobial photodynamic therapeutic properties against various microorganisms, especially Gram (+) bacteria. Additionally, they demonstrated high antibiofilm activities against S. aureus and P. aeruginosa. In addition, 100 % bacterial reduction was obtained for all the studied phthalocyanines against E. coli viable cells. Besides, the DNA cleavage and binding features of compounds ( QSiPc1–3 ) were studied using pBR322 DNA and CT-DNA, respectively. Furthermore, the human topoisomerase I enzyme inhibition activities of compounds QSiPc1 – 3 were studied. Anticancer properties of the water-soluble compounds were investigated using cell proliferation MTT assay. They exhibited anticarcinogenic activity against the human colon cancer cell line (DLD-1). Compounds QSiPc1 and QSiPc3 displayed a high anticarcinogenic effect on the DLD-1 cell line. The obtained results indicated that all the studied compounds may be effective biological agents and anticancer drugs after further investigations. 相似文献