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991.
Ya. O. Loginov G. G. Khudaigulov S. P. Chetverikov A. I. Melent’ev O. N. Loginov 《Applied Biochemistry and Microbiology》2011,47(3):311-314
Highly viscous polysaccharide (250–350 kDa) of an alginate nature with a predominance of α-L-guluronic acid (M/G = 0.22) was
obtained from Azotobacter vinelandi. The yield of polysaccharide was 20.5 ± 0.5 g/l when cultured in a medium containing molasses at a viscosity of the cultural
liquid of over 30000 cSt. The biopolymer is stable at pH 4.0–9.0 in a wide temperature range and well soluble in highly mineralized
water; it retains a high viscosity level and can be used in the petroleum industry for enhanced oil recovery. 相似文献
992.
I. A. Parfenov T. A. Revina P. P. Pashkovsky N. L. Radyukina T. A. Valueva 《Applied Biochemistry and Microbiology》2011,47(4):361-365
Product of polymerase chain reaction designated as PKPIJ-B was isolated after amplification from genomic DNA of potato (Solarium tuberosum L., Zhukov Jubilee cultivar) using the designed primers. Nucleotide sequence of PKPIJ-B was determined and amino acid sequence of protein was restored. Analysis of this sequence has allowed us to suggest that
isolated gene fragment encodes chymotrypsin and trypsin inhibitor protein (PKCI-23 potato Kunitz-type chymotrypsin inhibitor)
of potato tubers. 相似文献
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997.
BACKGROUND: Concern has been raised about the potential for adverse cognitive effects associated with the use of calcium-channel blockers (CCBs) in older people. This study was undertaken to examine prospectively the association between the use of these and other antihypertensive drugs and cognitive function. METHODS: The authors examined data from the Canadian Study of Health and Aging (CSHA), a population-based, prospective 5-year investigation of the epidemiology of dementia and other health problems in Canadians 65 years of age and older. The risk of cognitive decline, as indicated by a decline in performance on the Modified Mini-Mental State (3MS) examination over the 5-year period, was assessed in relation to the use of antihypertensive and diuretic drugs by 205 subjects with a history of hypertension and no evidence of dementia at baseline. RESULTS: The proportion of subjects whose cognitive performance declined over the study period was significantly higher in the group using CCBs than in the group using other antihypertensive agents (75% v. 59%). The adjusted odds ratio (OR) for a significant decline in cognitive performance (defined as a decrease in 3MS score of 10 points or more) was 2.28 (95% confidence interval [CI] 1.12-4.66) for subjects using CCBs. The adjusted ORs (and 95% CIs) for cognitive decline in subjects using selected antihypertensive agents or diuretics relative to those exposed to beta-blockers were as follows: angiotensin-converting-enzyme inhibitor, OR 1.36 (95% CI 0.41-4.55); diuretic or other antihypertensive drug, OR 1.45 (95% CI 0.51-4.14); dihydropyridine CCB (nifedipine), OR 1.94 (95% CI 0.52-7.27) and non-dihydropyridine CCB (diltiazem or verapamil), OR 3.72 (95% CI 1.22-11.36). INTERPRETATION: Older people taking CCBs were significantly more likely than those using other agents to experience cognitive decline. These findings are consistent with the results of previous cross-sectional research and emphasize the need for further trials to examine the associations between CCB use, blood pressure and cognitive impairment in elderly patients. 相似文献
998.
Kinga Michno David Knight Jorge M. Campussano Diana van de Hoef Gabrielle L. Boulianne 《PloS one》2009,4(9)
Much of our current understanding about neurodegenerative diseases can be attributed to the study of inherited forms of these disorders. For example, mutations in the presenilin 1 and 2 genes have been linked to early onset familial forms of Alzheimer''s disease (FAD). Using the Drosophila central nervous system as a model we have investigated the role of presenilin in one of the earliest cellular defects associated with Alzheimer''s disease, intracellular calcium deregulation. We show that expression of either wild type or FAD-mutant presenilin in Drosophila CNS neurons has no impact on resting calcium levels but does give rise to deficits in intracellular calcium stores. Furthermore, we show that a loss-of-function mutation in calmodulin, a key regulator of intracellular calcium, can suppress presenilin-induced deficits in calcium stores. Our data support a model whereby presenilin plays a role in regulating intracellular calcium stores and demonstrate that Drosophila can be used to study the link between presenilin and calcium deregulation. 相似文献
999.
M R Harris C S Kindle A F Abruzzini C W Pierce S E Cullen 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(3):1202-1208
We examined the antigen-presenting capacity of BCL1 tumor cells, which are capable of differentiating in vitro with respect to immunoglobulin synthesis/secretion under the influence of LPS. In vivo passaged BCL1 cells depleted of host cell contamination either by positive selection employing panning with anti-lambda reagents, or by elimination of latex-ingesting adherent cells, are capable of MHC-restricted antigen presentation to a GAT-immune T cell line. The BCL1 cells act as antigen-presenting cells when freshly explanted, but gradual loss of this function occurs, and cells cultured for 3.5 days cannot present antigen unless LPS is included during the culture period. BCL1 cells are equivalently Ia+ after the culture period with or without LPS stimulation. Other B cell lines capable of antigen presentation appear to express this trait constitutively, and the in vivo passaged BCL1 line is therefore unique among B cell lines in having antigen-presenting cell function that can be modulated. The data suggest that freshly explanted or LPS-cultured BCL1 cells are heterogeneous with respect to antigen-presenting capacity, and the basis for this heterogeneity is being sought. BCL1 offers an opportunity to study requirements for antigen presentation by B cells. 相似文献
1000.
Twelve cases of methanol poisoning are reviewed. The clinical presentation and biochemical features are described and the results of treatment with alkali, ethanol and dialysis reported. The outcome of methanol poisoning appears to be related more to the interval between the time of ingestion and the start of therapy and to the degree of acidosis than to the initial serum methanol level. Therefore, early and aggressive treatment with bicarbonate and ethanol and subsequent institution of hemodialysis are strongly recommended whenever methanol can be detected in the blood, especially when metabolic acidosis of the anion-gap type is present, when mental or visual disturbances are present, or when more than 30 ml of absolute methanol has been consumed. 相似文献