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71.
Srivastav A Singh B Chandra A Jamal F Khan MY Chowdhury SR 《Reproduction (Cambridge, England)》2004,127(3):343-357
The present study investigated regional modifications of glycosylation status, sperm association and functional significance of N- and O-linked glycoproteins in epididymal luminal fluid of the rhesus monkey (Macaca mulatta). The predominant glycoproteins of the epididymal luminal fluid that increase in the extent of glycosylation or unmasking of exposed epitopes in a region-specific, maturation-dependent manner, included those of 150, 116, 68, 64, 58 (N- and O-linked) and 170 kDa (O-linked). The higher expression of 40 (N-linked), 38 (N- and O-linked) and 60, 56 and 33 kDa (O-linked) glycoproteins in the proximal caput epididymal fluid was followed by alteration or reorganization of 60, 38 and 33 kDa (O-linked) glycoproteins in the distal segments of the epididymis. The association of epididymal fluid glycoproteins with maturing spermatozoa was identified by generating polyclonal antiserum against monkey caudal sperm membrane in female albino rabbits. The antiserum crossreacted strongly with 58 and 33 kDa epididymal fluid glycoproteins of monkeys and also reacted with 116, 68, 58, 56 and 33 kDa glycoproteins from Triton X-100 extracts of human spermatozoa, indicating the presence of antigenically related components in both species. The functional significance of epididymal fluid glycoproteins in sperm functions was investigated by raising antiserum against a heavily glycosylated 58 kDa glycoprotein (MEF1) of caudal epididymal fluid, which crossreacted with the Triton X-100 extracts of epididymal spermatozoa of monkey and ejaculated human spermatozoa on immunoblots. In an in vitro micro-sperm agglutination assay, anti-MEF1 serum agglutinated both rat caudal epididymal spermatozoa and human spermatozoa. MEF1 seemed to be involved in fertilization as demonstrated by inhibition of fertility (100%) in female albino rabbits and rats immunized with this protein. A sperm-agglutinating 58 kDa glycoprotein of rhesus monkey epididymis with functional significance in fertility was identified, thus indicating that it is a potential candidate for contraceptive vaccine development. 相似文献
72.
LiMn1.5Ni0.5O4 cathode material was prepared by sol–gel method and annealed at 850 °C for 15 h. The prepared powder was coated with ZnO by dissolving zinc acetate in methanol and LiMn1.5Ni0.5O4 powder was mixed in this solution followed by the continuous stirring for 4 h. The LiMn1.5Ni0.5O4 and ZnO-coated LiMn1.5Ni0.5O4 powder was structurally characterized using X-ray diffraction and scanning electron microscopy (SEM). The coin cell was fabricated using ZnO-coated LiMn1.5Ni0.5O4 as cathode materials, LiPF6, dissolved in ethylene carbonate (EC)/dimethyl carbonate (DMC) (1:1 wt ratio) as electrolyte, and Li foil as anode. It was found that ZnO-coated LiMn1.5Ni0.5O4 cathode materials had the initial discharge capacity of about 146 mA h g−1. The discharge capacity retention after 50 cycles was found to be nearly 97%. 相似文献
73.
The solvent extraction of concentrated acid was investigated from sulfate waste pickle liquors using Cyanex 923 (trialkylphosphine
oxide (TRPO); manufactured by Cytec Industries Inc., Woodland Park, NJ; provided by Cyanamid Canada Inc. (Markham, Canada))
as an extractant. The effect of various parameters was studied such as extractant concentration, organic-to-aqueous phase
ratio, temperature. and retention time on acid extraction from the waste pickle liquor to the organic phase, After the saturation
of the organic phase with sulfuric acid, stripping studies were performed to back-extract the pure acid into the aqueous phase.
The raffinate of the solvent extraction process that contains both ferrous and ferric iron as well as trace impurities was
subjected to oxidation and hydrothermal treatment to precipitate iron with a well-defined pseudo-cubic morphology and a high
coercivity value that renders it suitable for high-grade ferrite production. 相似文献
74.
Valence M. K. Ndesendo Yahya E. Choonara Leith C. R. Meyer Pradeep Kumar Lomas K. Tomar Charu Tyagi 《Drug development and industrial pharmacy》2015,41(8):1274-1287
Context and objective: The aim of this study was to develop, characterize and evaluate a mucoadhesive caplet resulting from a polymeric blend (polymeric caplet) for intravaginal anti-HIV-1 delivery.Materials and methods: Poly(lactic-co-glycolic) acid, ethylcellulose, poly(vinylalcohol), polyacrylic acid and modified polyamide 6, 10 polymers were blended and compressed to a caplet-shaped device, with and without two model drugs 3′-azido-3′-deoxythymidine (AZT) and polystyrene sulfonate (PSS). Thermal analysis, infrared spectroscopy and microscopic analysis were carried out on the caplets employing temperature-modulated DSC (TMDSC), Fourier transform infra-red (FTIR) spectrometer and scanning electron microscope, respectively. In vitro and in vivo drug release analyses as well as the histopathological toxicity studies were carried out on the drug-loaded caplets. Furthermore, molecular mechanics (MM) simulations were carried out on the drug-loaded caplets to corroborate the experimental findings.Results and discussion: There was a big deviation between the Tg of the polymeric caplet from the Tg's of the constituent polymers indicating a strong interaction between constituent polymers. FTIR spectroscopy confirmed the presence of specific ionic and non-ionic interactions within the caplet. A controlled near zero-order drug release was obtained for AZT (20 d) and PSS (28 d). In vivo results, i.e. the drug concentration in plasma ranged between 0.012–0.332?mg/mL and 0.009–0.256?mg/mL for AZT and PSS over 1–28 d.Conclusion: The obtained results, which were corroborated by MM simulations, attested that the developed system has the potential for effective delivery of anti-HIV-agents. 相似文献
75.
Mukesh KumarBhabani K. Satapathy Amar Patnaik Dilip K. KolluriBharat S. Tomar 《Tribology International》2011,44(4):359-367
Composite friction materials based on synergistic ternary combination of potassium titanate whiskers, aramid fibre and graphite have been characterized for friction braking performance on Krauss friction tester. The dynamics of friction build-up and friction-decay as a function of number of braking instances and modes of braking cycles have been found to be more consistent in the composites with ≥7.5 wt% of aramid fibres whereas the absolute friction effectiveness remained higher in the composites with ≥25 wt% of potassium titanate whiskers. Wear surface morphology has revealed topographical variations and their underlying role in controlling the friction and wear performance. 相似文献
76.
77.
R. S. Tomar Prakash Bhartia 《Journal of Infrared, Millimeter and Terahertz Waves》1986,7(9):1281-1295
New design data for an open suspended microstripline is reported. Two most commonly used substrate materials, namely RT-Duroid (?r=2.22) and fused quartz (?r=3.78) are considered. Effects of dispersion and strip thickness are included in the results which are based on a fullwave spectral-domain analysis. The data, which is computed over the complete practical ranges of frequency and parameter values, is much more reliable than the currently available quasistatic results. 相似文献
78.
79.
The strength and elongation to fracture of spray deposited Al-Si-Pb alloys were studied as a function of lead content, silicon content, and distance from the centre to periphery of the deposit. It is found that the ultimate tensile strength, proof stress and elongation to fracture decrease, linearly and exponentially, with the increase in lead content and porosity of the deposit, respectively. Both the strengths and elongation to fracture linearly increase with increasing distance from the centre to periphery of the deposit. The ultimate tensile strength and proof stress are higher at a higher silicon content and they have a linear relationship with the hardness of the deposit. 相似文献
80.
Suprio R. Paul Suraj K. Nayak Yamini Yogalakshmi Vinay K. Singh Archana Rath Indranil Banerjee 《Polymer-Plastics Technology and Engineering》2018,57(6):540-547
The present study reports the analysis of properties of tamarind gum-based hydroethanolic physical hydrogels. The extent of hydrogen bonding in hydrogels decreased with an increase in tamarind gum content. The hydrogel with the highest tamarind gum content was found to be highly stable in terms of mechanical properties. There was a decrease in the resistive component of the hydrogels with an increase in tamarind gum content. The drug release from the hydrogels increased with an increase in the tamarind gum content. The antimicrobial activity of the drug-loaded hydrogels against Escherichia coli was excellent. 相似文献