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41.
International Journal of Peptide Research and Therapeutics - The development of peptide-based formulations presents numerous challenges to the formulator due to their complexity, delicate structure...  相似文献   
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In the present study, an in vitro regeneration protocol for Glossonema varians (Stocks) Benth. ex Hook.f. of family Asclepiadaceae was optimized. Cotyledonary nodes of in vitro cultured seedlings were used as explants for activation of axillary shoot buds. Axillary shoot buds were initially activated on 0.1 mg L?1 6-benzylaminopurine (BAP) and then multiplied on 0.05 mg L?1 BAP. Shoots were rooted in vitro on 1/4 strength Murashige and Skoog medium containing 0.1 mg L?1 2-naphthoxyacetic acid and 100 mg L?1 activated charcoal. The cultures were maintained in a 12 h photoperiod at 40–50 μmol m?2 s?1 spectral flux photon, 25–30?±?2°C, and 60% relative humidity (RH). Up to 80% of in vitro regenerated plantlets were acclimatized on soilrite in cotton-plugged culture tubes in the greenhouse. This protocol can be a useful method to mass propagate and conserve this rare plant to balance biodiversity in the desert ecosystem.  相似文献   
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Lytic phages infect their bacterial hosts, use the host machinery to replicate, and finally lyse and kill their hosts, releasing progeny phages. Various mathematical models have been developed that describe these phage-host viral dynamics. The aim of this study was to determine which of these models best describes the viral dynamics of lytic RNA phage MS2 and its host Escherichia coli C-3000. Experimental data consisted of uninfected and infected bacterial cell densities, free phage density, and substrate concentration. Parameters of various models were either determined directly through other experimental techniques or estimated using regression analysis of the experimental data. The models were evaluated using a Bayesian-based model discrimination technique. Through model discrimination it was shown that phage-resistant cells inhibited the growth of phage population. It was also shown that the uninfected bacterial population was a quasispecies consisting of phage-sensitive and phage-resistant bacterial cells. When there was a phage attack the phage-sensitive cells died out and the phage-resistant cells were selected for and became the dominant strain of the bacterial population.  相似文献   
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Human gastric lipase (HGL) is a sulfhydryl enzyme which has been shown by Gargouri et al. (Gargouri, Y., Moreau, H., Piéroni, G. and Verger, R. (1988) J. Biol. Chem. 263, 2159-2162) to be inhibited by hydrophobic disulfides. Since HGL is involved in the digestion and absorption of dietary fats we have investigated in vitro the ability of ajoene, a natural disulfide to inactivate HGL. Ajoene is derived from ethanolic garlic extracts. The finding that ajoene inactivates HGL is consistent with the fact that it is reactive towards sulfhydryl compounds and also corroborates previous reports on the ability of garlic to lower triacylglycerol blood levels. These data may explain the age-old Mediterranean and Oriental belief in the 'blood-thinning' effects of garlic on a molecular and physiological basis.  相似文献   
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E G Niles  R K Jain 《Biochemistry》1981,20(4):905-909
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Plasmonics - The present study focuses on the employment of TiO2 (titanium dioxide) film as an anti-reflective coating (ARC) on thin crystalline silicon (Si)-based solar cells along with the...  相似文献   
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OBJECTIVE: To assess the efficacy of the nucleic acid amplification (NAA) technique for Mycobacterium tuberculosis (MTB) complex from archival fine needle aspirate (FNA) smear scrapings of confirmed cases of extrapulmonary tuberculosis (EPTB) for a retrospective diagnosis of EPTB as compared to NAA from fresh FNA material from the same cases. STUDY DESIGN: Smear scrapings from 51 cases; 33 cases of tuberculous lymphadenitis (from patients who had undergone NAA 1 year before for MTB from fresh FNA material); 13 negative controls from nontuberculous, archival FNA smears; and 5 known acid-fast bacilli (AFB)-positive sputum smears, were subjected to NAA using the IS6110 primer sequence of M tuberculosis. Ziehl-Neelsen staining was done in all the smears. RESULTS: Of the 33 cases of tuberculous lymphadenitis, 15 (45.4%) were AFB positive and 18 (64.5%) AFB negative. MTB NAA was positive in 73.3% (11 of 15 AFB-positive cases) in the freshly aspirated material and was observed in 60% (9 of 15 AFB-positive cases) when done on DNA extracted from the archival smear scrapings of the same cases. Similarly, in the 18 AFB-negative cases, MTB NAA positivity was 72.2% (13 of 18) on fresh material and 44.4% (8 of 18) on archival smear scrapings from the same AFB-negative cases. Overall NAA positivity was 51.5% for archival smear scrapings as compared to 71% for fresh FNA of the same cases. CONCLUSION: Low NAA sensitivity of MTB DNA in archival material of known tuberculous cases limits the routine use of NAA based retrospective molecular diagnosis of MTB complex.  相似文献   
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