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781.
Al-Kinani Maha A. Haider Adawiya J. Al-Musawi Sharafaldin 《Plasmonics (Norwell, Mass.)》2021,16(4):1107-1117
Plasmonics - The purpose of this study is to prepare nanoencapsulation synthesized with a new formulation of Fe@Au-CS-CU-FA nanoparticle (NPs) by pulsed laser ablation in liquid (PLAL) method as... 相似文献
782.
The effect of testosterone on regulation of epididymal protein synthesis has been investigated in castrated rhesus monkeys (Macaca mulatta). The proteins in the treated monkeys were characterized using polyacrylamide gel electrophoresis (under nondenaturing and denaturing conditions) and electrofocusing. At least four distinct proteins have been shown to be synthesized by the monkey epididymis under testosterone influence. Two of these proteins were detected following two days of testosterone treatment while the other two proteins were detected after a six-day treatment period. None of these proteins was detectable in monkeys treated with estradiol for six days. Electrofocusing of epididymal cytosol proteins from untreated and testosterone-treated and castrated monkeys also confirmed the presence of four androgen-dependent proteins in this species. The isoelectric points of these proteins were shown to range between 5.8 and 6.4. The molecular weights of these proteins were found to vary between 47,500 and 66,000. The in vitro incorporation of 3H-labeled amino acids was markedly greater in the androgen-primed epididymis as compared with the control tissue. 相似文献
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784.
Abstract. The interdivisional times of Friend murine erythroleukaemia cells which are growing continuously, or during terminal erythroid differentiation after exposure to dimethyl sulphoxide (DMSO), were determined by time lapse video photography. the median interdivisional times were found to increase from 11.75 hr before exposure to DMSO, to 24.0 hr at 72 hr after exposure. This increase in median interdivisional time was accompanied by an increase in heterogeneity of interdivisional times (% CV = 8-5 → 40.8), by an increase in the similarity of sister interdivisional times (ryy = 0.622 → 0.925), and by a decrease in the fraction of cells observed to divide ( F = 1. 0 → 0.807). Cells exposed to DMSO for 72 hr can be induced to divide at least once with nearly normal interdivisional times, if they are resuspended at a tenfold higher cell concentration. Computer simulations of cell cycle regulation, based on the opposing reactions model of Murphy, generate interdivisional time distributions which resemble the experimental data better than the single transition probability model of Smith and Martin. 相似文献
785.
Up to 90% of the gamma-Hexachlorocyclohexane (gamma-HCH) applied to an anaerobic mixed bacterial flora enriched from an arable soil were degraded within 4-5 days. Degradation resulted in a rapid release of chloride and in formation of chlorine-free volatile metabolites. CO2 formation from the molecule was not detected. Investigations with 14C/3H- and 36Cl/3H double-labelled gamma-HCH indicated that the release of Cl and H did not occur in the ratio of 1:1. More Cl than H was split off. The volatile compounds contained more 14C than 3H. Gas chromatographic studies also showed the rapid decrease of gamma-HCH and the formation of several metabolities. gamma-Pentachlorocyclohexene was nto detected. Increasing O2-contents in the gas phase of cultures resulted in decreases of the compound's degradation. Release of chloride and of volatile metabolites were observed with O2 contents in the gas phase up to 5%. alpha-HCH was also, but more slowly as with gamma-HCH, degraded by the anaerobic mixed flora. Chloride was released and volatile, chlorine-free metabolites were found. 相似文献
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789.
Ahmad Waseem E. Birgitte Lane Dolores Harrison Naushin Waseem 《Experimental cell research》1996,223(2):203
Keratin filaments in simple epithelial cells are heteropolymers of keratin 8 (K8) and keratin 18 (K18), which can be stained by the monoclonal antibody (MAb) LE61. This antibody has been widely used to study keratin expression in normal and neoplastic tissues. In this study we have found that MAb LE61 does not react with individual keratin polypeptides either derived from natural sources or expressed as recombinant proteins inEscherichia coli.However, when K8 or K18 bound to nitrocellulose were incubated with complementary keratin they became reactive with this antibody. A mixture of K8 and K18 in solution also reacted strongly with the MAb LE61 in ELISA. These observations suggest that the antibody recognizes a discontinuous epitope on the keratin complex. The antibody also reacted with complexes of K8 and K18 with other keratins. To locate the epitope of this antibody we have expressed K8 and K18 fragments, deleted from the amino- and carboxyl-termini, as fusion proteins with glutathioneS-transferase. These fragments were able to form a heterotypic complex with the complementary keratin. Binding of the MAb LE61 to these complexes mapped the two halves of the epitope on K8, between residues 353 and 367, and on K18, between residues 357 and 385. The two halves of the epitope appear to be in close association in the heterotypic complex since deletions from the amino-terminus did not influence the antibody binding. The highly conserved nature of this epitope in both type I and type II keratins could explain the MAb LE61 reactivity with complexes of K8 or K18 with other keratins. 相似文献
790.
The hypothalamo-neurohypophysial complex of Ailia coila is well demonstrated with the help of in situ staining procedure. Both pars magnocellularis and pars parvocellularis components of the nucleus preopticus contribute to the formation of the right and the left main neurosecretory tracts. Anterior one third of these tracts are loosely set and posteriorly they became more compact. From the posterior two thirds of the main tracts several pairs of lateral tracts were given off which join at the midline to form the paired median tracts. The median and the main tracts jointly enter the pituitary as the common tract. The common tract on entering the pituitary often divides into two or more branches and enter the pars intermedia independently. The rostral pars distalis is least innervated by the neurosecretory axons. Since the proximal pars distalis has varying amount of AF-positive cells, and the pars intermedia has the bulk of the neurosecretory axons both these regions are stained dark in the in situ preparations. Bulk preparations provide a clear topographic picture of the entire neurosecretory system, which is very difficult to visualise in tissue sections and in their reconstructions. 相似文献