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101.
The aim of this study was to determine the relationship between serum and cerebrospinal fluid (CSF) magnesium (Mg+2) levels, Glasgow Coma Scores (GCS), and 7-day mortality in acute stroke patients. Patients with acute ischemic or hemorrhagic stroke arriving within the first 3 h of symptoms were included in the study. The control group consisted of healthy volunteers. GCS was determined, and blood and CSF samples were taken in order to establish serum and CSF glucose, Mg+2, sodium, potassium, calcium, and chlorine levels. Mortality was recorded at 7 days after admission. CSF Mg+2 in the ischemic infarct group was significantly lower than in the control group (p = 0.006). CSF Mg+2 in the ischemic infarct patients with a GCS ≤ 8 were significantly lower (p = 0.002) than controls and in ischemic infarct patients with a GCS ≥9. In the ischemic stroke patients, CSF Mg+2 and GCS were significantly correlated (r = 55, p = 0.031). CSF Mg+2 levels in ischemic stroke patients who died within 7 days were significantly lower than controls, ischemic stroke patients who survived, and hemorrhagic stroke patients who died (p = 0.002, p = 0.042, and p = 0.005, respectively). Low CSF Mg+2 levels in patients with acute ischemic stoke at admission predicted a higher 1-week mortality.  相似文献   
102.
Fucosylated structures participate in a wide range of pathological processes in eukaryotes and prokaryotes. The impact of fucose on microbial pathogenesis, however, has been less appreciated in arthropods of medical relevance. Thus, we used the tick‐borne bacterium Anaplasma phagocytophilum– the agent of human granulocytic anaplasmosis to understand these processes. Here we show that A. phagocytophilum uses α1,3‐fucose to colonize ticks. We demonstrate that A. phagocytophilum modulates the expression of α1,3‐fucosyltransferases and gene silencing significantly reduces colonization of tick cells. Acquisition but not transmission of A. phagocytophilum was affected when α1,3‐fucosyltransferases were silenced during tick feeding. Our results uncover a novel mechanism of pathogen colonization in arthropods. Decoding mechanisms of pathogen invasion in ticks might expedite the development of new strategies to interfere with the life cycle of A. phagocytophilum.  相似文献   
103.
Serum paraoxonase (PON1) is a key enzyme related to high‐density lipoprotein (HDL)‐cholesterol particle. It can prevent the oxidation of low‐density lipoprotein (LDL) and HDL. The present article focuses on the in vitro inhibition role of some antiepileptic drugs (AEDs) such as valproic acid, gabapentin, primidone, phenytoin, and levetiracetam on human paraoxonase (hPON1). Therefore, PON1 was purified from human serum with a specific activity of 3976.36 EU/mg and 13.96% yield by using simple chromatographic methods. The AEDs were tested at various concentrations, which showed reduced in vitro hPON1 activity. IC50 values for gabapentin, valproic acid, primidone, phenytoin, and levetiracetam were found to be 0.35, 0.67, 0.87, 6.3, and 53.3 mM, respectively. Ki constants were 0.261 ± 0.027, 0.338 ± 0.313, 0.410 ± 0.184, 10.3 ± 0.001, and 43.01 ± 0.003 mM, respectively. Gabapentin exhibited effective inhibitory activity as compared with the other drugs. The inhibition mechanisms of all compounds were noncompetitive.  相似文献   
104.
Aldose reductase (AR) inhibitors have vital importance in the treatment and prevention of diabetic complications. In this study, rat kidney AR was purified 19.34-fold with a yield of 3.49% and a specific activity of 0.88?U/mg using DE-52 Cellulose anion exchange chromatography, gel filtration chromatography and 2′5′ ADP Sepharose-4B affinity chromatography, respectively. After purification, the in vitro inhibition effects of some phenolic acids (tannic acid, chlorogenic acid, sinapic acid, protocatechuic acid, 4-hydroxybenzoic acid, p-coumaric acid, ferulic acid, vanillic acid, syringic acid, α-resorcylic acid, 3-hydroxybenzoic acid and gallic acid) were investigated on purified enzyme. We determined IC50, Ki values and inhibition types of these phenolic acids. As a result, tannic and chlorogenic acid had a strong inhibition effect. On the other hand, gallic acid had a weak inhibition effect. In this study, all phenolic acids except for chlorogenic acid and p-coumaric acid showed non-competitive inhibition effects on rat kidney AR.  相似文献   
105.
106.
Gerodontology 2010; doi: 10.1111/j.1741‐2358.2009.00353.x
Reliability and comparison of two facial measurements to detect changes of occlusal vertical dimension in complete denture wearers Background: Facial measurements are frequently used to determine OVD. However, the reliability of neither the method nor the chosen landmarks has been cleared yet. Objective: This study compares the reliability of two facial measurements, subnasal (SN) to chin (C) and tip of the nose (TN) to C, for determining occlusal vertical dimension (OVD). Materials and methods: Thirty edentulous subjects with adequate neuromuscular co‐ordination, without signs and symptoms of temporomandibular disorders and who had been wearing complete dentures for at least 5 years were enrolled. A modified central bearing device was used to alter the OVD and facial measurements were made with a digital caliper. Student’s t‐test was used to compare the two measurements. Interobserver and intraobserver reliability were evaluated with Spearman’s rho correlation test. Results: TN–C distance had an improved correlation with the changes in intraoral alterations than SN–C distance. While the means of the changes in facial measurements were in good agreement with the intraoral alterations, the ranges were wide. Both interobserver and intraobserver reliability of the measurements were high. Conclusion: While facial measurement is not a good predictor of OVD, TN–C distance appears to be more reliable than SN–C distance.  相似文献   
107.
This paper presents superbinding, a concept that represents integrative oscillatory dynamics over the time and space axes. Principle of superposition describes integration over the temporal axis; selectively distributed and selectively coherent oscillatory neural populations describe integration over the spatial axis. Integrative activity is a function of the coherences between spatial locations of the brain; these coherences vary according to the type of sensory and or cognitive event and possibly the consciousness state of the species. Complex percepts and integrative activity in general that is achieved by superbinding supported by the neurons-brain theory may replace the Sherringtonian integrative brain function that is achieved through the single neuron doctrine.

Results of recent experiments related to the percept of the grandmother-face support our concept of super-synergy in the whole brain in order to explain manifestation of Gestalts and Memory-Stages. The strategies of the Grandmother paradigm may open new horizons in search of memories or evolving memories, and possibly provide relevant clinical applications.  相似文献   

108.
During P deficiency, the increased activity of malate dehydrogenase (MDH, EC 1.1.1.37) can lead to malate accumulation. Cytosolic- and nodule-enhanced MDH (cMDH and neMDH, respectively) are known isoforms, which contribute to MDH activity in root nodules. The aim of this study was to investigate the role of the cMDH isoforms in nodule malate supply under P deficiency. Nodulated lupins (Lupinus angustifolius var. Tanjil) were hydroponically grown at adequate P (+P) or low P (−P). Total P concentration in nodules decreased under P deficiency, which coincided with an increase in total MDH activity. A consequence of higher MDH activity was the enhanced accumulation of malate derived from dark CO2 fixation via PEPC and not from pyruvate. Although no measurable neMDH presence could be detected via PCR, gene-specific primers detected two 1 kb amplicons of cMDH, designated LangMDH1 (corresponding to +P, HQ690186) and LangMDH2 (corresponding to −P, HQ690187), respectively. Sequencing analyses of these cMDH amplicons showed them to be 96% identical on an amino acid level. There was a high degree of diversification between proteins detected in this study and other known MDH proteins, particularly those from other leguminous plants. Enhanced malate synthesis in P-deficient nodules was achieved via increased anaplerotic CO2 fixation and subsequent higher MDH activities. Novel isoforms of cytosolic MDH may be involved, as shown by gene expression of specific genes under P deficiency.  相似文献   
109.
110.
The biochar is an important carbon-rich product that is generated from biomass sources through pyrolysis. Biochar (charcoal) can be both used directly as a potential source of solid biofuels and as soil amendments for barren lands. The aim of this study was investigate influence of pyrolysis temperature on the physicochemical properties and structure of biochar. The biochars were produced by pyrolysis of rapeseed (Brassica napus L.) using a fixed-bed reactor at different pyrolysis temperatures (400–700°C). The produced biochars were characterized by proximate and elemental analysis, Brunauer–Emmett–Teller (BET) surface area, particle size distributions, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy. The results showed that both chemical and surface properties of the biochars were significantly affected by the pyrolysis temperature. Aromatic hydrocarbons, hydroxyl and carbonyl compounds were the majority components of the biochar. The biochar obtained at 700°C had a high fixed carbon content (66.16%) as well as a high heating value, and therefore it could be used as solid fuel, precursor in the activated carbons manufacture (specific surface area until 25.38 m2 g?1), or to obtain category-A briquettes.  相似文献   
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