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991.
Cefepime/amikacin in the empirical antibacterial therapy for patients with hemoblastosis of different forms] 总被引:1,自引:0,他引:1
The results of the use of cefepime (Maxipime) combination with amikacin vs ceftriaxon combination with amikacin in the treatment of 80 patients with different forms of hemoblastosis are presented. Severe infectious complications in the patients were associated with prolonged and deep neutropenia during inductive or antirelapsing chemotherapy. All the patients in the trial were from the group of high risk of infectious complications with the blood neutrophil count under 100 cells/microliter. The duration of neutropenia averaged 12 days (7 to 15). The average period of the treatment with cefepime and amikacin equaled to 13 days (8 to 16). The treatment with cefepime + amikacin was successful in 38 out of 40 patients (95%). The average period of the treatment with ceftriaxon and amikacin equaled to 14 days (7 to 18). The efficacy of the treatment with ceftriaxon + amikacin was 60% (24 patients out of 40). 相似文献
992.
New gene assignments using a complete, characterized sheep-hamster somatic cell hybrid panel 总被引:4,自引:0,他引:4
The generation and characterization of new sheep-hamster cell hybrids is reported from the fusion of sheep white blood cells with six different hamster auxotrophs. Selection from these and previously generated cell hybrids has led to the production of a panel of 30 hybrids covering the complete sheep genome of 28 chromosomes. Over half of the cell hybrids in this panel contain single sheep chromosomes. By complementation, the following new assignments have been made using the panel: phosphoribosyl N-formylglycinamide amidotransferase (PRFGA) to sheep chromosome (chr) 11; adenylosuccinate synthetase (ADSS) to sheep chr 12; adenylosuccinate lyase (ADSL) to sheep chr 3q; 3-hydroxy-3-methylglutaryl-coenzyme A synthase (HMGCS) to sheep chr 16; dihydrofolate reductase (DHFR) to sheep chr 5; and adenine phosphoribosyltransferase (APRT) to sheep chr 14. The gene phosphoribosylaminoinidazole-carboxamide formyltransferase/Inosinicase (PRACFT) has now been regionally assigned to chr 2q. By isozyme analysis, phosphogluconate dehydrogenase (PGD) was assigned to sheep chr 12, anchoring the sheep syntenic group U1 to this chromosome, and mannose phosphate isomerase (MPI) was assigned to sheep chr 18. Furthermore, the chromosomal assignment of 110 microsatellites was confirmed using this cell panel. 相似文献
993.
994.
E. Cortés A.A. Kirk J.A. Goolsby P.J. Moran A.E. Racelis M.A. Marcos-García 《Biocontrol Science and Technology》2011,21(11):1369-1373
Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those from nine sites without scale. 相似文献
995.
Shreaya Chakroborty Clark Briggs Megan B. Miller Ivan Goussakov Corinne Schneider Joyce Kim Jaime Wicks Jill C. Richardson Vincent Conklin Benjamin G. Cameransi Grace E. Stutzmann 《PloS one》2012,7(12)
Alzheimer’s disease (AD) is a devastating neurodegenerative condition with no known cure. While current therapies target late-stage amyloid formation and cholinergic tone, to date, these strategies have proven ineffective at preventing disease progression. The reasons for this may be varied, and could reflect late intervention, or, that earlier pathogenic mechanisms have been overlooked and permitted to accelerate the disease process. One such example would include synaptic pathology, the disease component strongly associated with cognitive impairment. Dysregulated Ca2+ homeostasis may be one of the critical factors driving synaptic dysfunction. One of the earliest pathophysiological indicators in mutant presenilin (PS) AD mice is increased intracellular Ca2+ signaling, predominantly through the ER-localized inositol triphosphate (IP3) and ryanodine receptors (RyR). In particular, the RyR-mediated Ca2+ upregulation within synaptic compartments is associated with altered synaptic homeostasis and network depression at early (presymptomatic) AD stages. Here, we offer an alternative approach to AD therapeutics by stabilizing early pathogenic mechanisms associated with synaptic abnormalities. We targeted the RyR as a means to prevent disease progression, and sub-chronically treated AD mouse models (4-weeks) with a novel formulation of the RyR inhibitor, dantrolene. Using 2-photon Ca2+ imaging and patch clamp recordings, we demonstrate that dantrolene treatment fully normalizes ER Ca2+ signaling within somatic and dendritic compartments in early and later-stage AD mice in hippocampal slices. Additionally, the elevated RyR2 levels in AD mice are restored to control levels with dantrolene treatment, as are synaptic transmission and synaptic plasticity. Aβ deposition within the cortex and hippocampus is also reduced in dantrolene-treated AD mice. In this study, we highlight the pivotal role of Ca2+ aberrations in AD, and propose a novel strategy to preserve synaptic function, and thereby cognitive function, in early AD patients. 相似文献
996.
E Karnaukhova W M Niessen U R Tjaden J Raap J Lugtenburg J van der Greef 《Analytical biochemistry》1989,181(2):271-275
In order to develop direct methods for determining the extent of metabolic incorporation of isotopically labeled amino acids into a protein, the determination of deuterated tryptophan in [2H5]tryptophan-bacteriorhodopsin was investigated. The isotopically modified protein was subjected to alkaline hydrolysis. After phenyl isothiocyanate derivatization of the hydrolysate, the mixture was separated by reversed-phase liquid chromatography. Field desorption mass spectrometry and thermospray mass spectrometry were investigated for their ability to determine the ratio between [2H5]tryptophan and total tryptophan in the collected fractions. In order to check the procedure a set of known tryptophan/[2H5]tryptophan mixtures were passed through the same derivatization, HPLC separation, and lyophilization procedure as used for the biological samples. 相似文献
997.
Gradually altered synthetic entities were employed as molecular probes, and arachidonic acid, ADP, human alpha-thrombin and the Ca2+ ionophore A23187 as aggregation-inducing agents, in a comprehensive study on the response profile of human blood platelets with an emphasis on the effects of exogenous and increased intracellular Ca2+. Corroborating further previous conclusions, some representative carbamoylpiperidine derivatives, at concentrations effecting substantial inhibition of ADP-induced aggregation, failed to retain that effect when 5.0 mM Ca2+ was introduced into the otherwise identical test medium; reference compounds chlorpromazine and propranolol registered corresponding inhibitory patterns. At increased concentrations the compounds' inhibitory potency was regenerated even in the presence of 5 mM Ca2+. In fact, in sufficiently high concentrations, the compounds were even capable of inhibiting aggregation elicited by 15 microM of the ionophore A23187; so did chlorpromazine and propranolol. Another set of congeners revealed the striking sensitivity of ionophore A23187-induced human blood platelet aggregation to the surface active potencies of inhibitor molecules. The loss in inhibitory potency was directly related to the lesser hydrophobic character of the molecule. 相似文献
998.
Phosphate activated glutaminase in synaptosomal enriched preparation from rat brain is very sensitive to inhibition by low concentration of glutamate, ammonia and 2-oxoglutarate when added to the incubation medium at pH 7.6. By increasing the concentration of either of these compounds up to 0.5 mM a pronounced initial inhibition is followed by little or no further effect when the concentration is increased beyond this level. By lowering the pH of the reaction mixture to 7.0, the inhibition by glutamate is almost abolished and that of ammonia reduced. Glutamate inhibits mainly the N-ethylmaleimide-sensitive fraction of glutaminase which previously is suggested to be localized to the outer phase of the mitochondrial inner membrane, whereas ammonia inhibits both the N-ethylmaleimidesensitive and-insensitive fraction. Evidence has been produced to show that the inhibition by 2-oxoglutarate is caused by glutamate formation by aminotransferase reactions. Since 2-oxoglutarate is produced by the tricarboxylic acid cycle, the operation of this cycle may regulate the glutaminase reaction by controlling glutamate formation via the aminotransferase reactions.Abbreviations used NEM
N-ethylmaleimide
- PAG
phosphate activated glutaminase
- AOA
aminooxyacetic acid 相似文献
999.
E C Chew 《Acta anatomica》1980,108(2):156-159
Tannic acid was found to fix and stain glycocalyx heavily. After removal of the major component of surface glycopeptides by trypsin, the surface coat was stained vaguely, and after the treatment with collagenase, the surface coat was moderately stained. It is concluded that tannic acid stained non-specific surface glycopeptides. 相似文献
1000.