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排序方式: 共有317条查询结果,搜索用时 15 毫秒
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Y.T. KO 《Journal of Food Biochemistry》2006,30(6):732-748
The cellular receptor of an oyster juice borne phage OJ367 was found in the outer membrane (OM) of its host Escherichia coli. The total cell envelope (TCE) was fractionated by differential extraction and it was found that the OM possesses phage neutralization ability. The OM was purified by diethylaminoethyl cellulose column chromatography to screen for the phage recognition moiety. A homogeneous, 39‐kDa OM protein (Omp) with receptor activity was eluted. It was a peptidoglycan (PG)‐associated protein which showed trypsin resistance. Lipopolysaccharide (LPS) had no effect on its receptor activity either when coexisting in the column fractions or when the isolated LPS was mixed with the Omp. Mutants resistant to lysis by phage OJ367 were isolated. The amount of the 39‐kDa and another PG‐associated 37‐kDa protein decreased significantly in the TCE of the mutant. The 39‐kDa Omp may serve as the cellular receptor for adherence of the coliphage, whereas the 37‐kDa protein is also involved in the infection mechanism. 相似文献
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JA Vivian S Kishioka ER Butelman J Broadbear KO Lee JH Woods 《Canadian Metallurgical Quarterly》1998,286(2):697-703
This study characterized the antinociceptive, respiratory and heart rate effects of the cannabinoid receptor agonists Delta-9-tetrahydrocannabinol (Delta-9-THC) and WIN 55212 ((R)-(+)-2, 3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrol-[1,2,3-de]-1, 4-benzoxazin-6-yl)(1-naphtalenyl)methanone monomethanesulfonate), N-arachidonyl ethanolamide (anandamide) and the mu and kappa opioid receptor agonists heroin and U69593, alone and in conjunction with a cannabinoid receptor antagonist, SR 141716A [N-(piperidin-1-1-yl)-5-(4-chlorophenyl)-1(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride] and an opioid receptor antagonist, quadazocine, in rhesus monkeys (Macaca mulatta). Using 12 adult rhesus monkeys, latencies to remove the tail from a 50 degrees C water bath, respiration in 5% CO2 and heart rate were measured. When administered alone, SR 141716A (1.8, 5.6 mg/kg i.m.) did not alter nociception, respiration or heart rate. Delta-9-THC (0.1-10 mg/kg i.m.) and WIN 55212 (0.1-10 mg/kg i.m.) dose-dependently increased antinociception and dose-dependently decreased respiratory minute and tidal volumes and heart rate. These antinociceptive, respiratory and heart rate effects were reversed by SR 141716A but not by the opioid antagonist quadazocine (1 mg/kg i.m.). Anandamide (10 mg/kg i.m.) also produced antinociception. Heroin (0.01-10 mg/kg i.m.) and U69593 (0.01-3.2 mg/kg i.m.) also dose-dependently increased antinociception and decreased respiratory and heart rate measures; these effects were antagonized by quadazocine but not by SR 141716A. These results demonstrate selective and reversible antagonism of cannabinoid behavioral effects by SR 141716A in rhesus monkeys. 相似文献
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P Pietarinen-Runtti KO Raivio M Saksela TM Asikainen VL Kinnula 《Canadian Metallurgical Quarterly》1998,19(2):286-292
OBJECTIVE: The measurement of total serum testosterone has an established clinical role in the management of male hypogonadism and female androgen excess disorders. We studied the between-kit variability and precision of six different commercially available testosterone assays and compared them with an established in-house method. DESIGN: Laboratory observational prospective study. SETTING: Tertiary university medical center clinical laboratory. PATIENT(S): Three groups of samples each of men (n = 36) and women (n = 15) who had high, normal, or low levels of sex hormone-binding globulin (SHBG), respectively, were studied. INTERVENTION(S): Individual and pooled (male and female) serum samples were analyzed for total testosterone concentration using six different commercially available assays and one in-house method. MAIN OUTCOME MEASURE(S): The between-kit variability and the effect of the mean (+/- SD) SHBG level were determined, the results obtained with the use of the kits and the in-house method were compared, and the intraassay variability (i.e., precision) was evaluated. RESULT(S): Male samples demonstrated a 26.3%-40.8% variance in the results obtained with different kits, which was greatest for samples with the lowest SHBG levels. For female samples, between-kit variability ranged from 57%-115% (average, 77%). The percent deviation of the results obtained with the use of commercial methods from those obtained with the use of our in-house assay was greater for men (mean variance, 194%) than for women (mean variance, 67%). The female pool intraassay coefficient of variation was 3.8% with the use of the in-house method and ranged from 8.9%-21.2% with the use of the commercial kits. The male pool intraassay coefficient of variation was 3.1% with the use of the in-house method and ranged from 3.3%-5.5% with the use of the commercial kits. CONCLUSION(S): Most commercially available kits for measuring the total serum testosterone level demonstrated significant between-kit variability, which was greatest for female samples. Further, samples with the lowest SHBG levels had the highest between-kit variances. These data strongly suggest that the measurement of total serum testosterone using commercial kits may have limited utility, particularly for the detection of hyperandrogenemia. 相似文献
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KO Yeates BG Enrile N Loss E Blumenstein DC Delis 《Canadian Metallurgical Quarterly》1995,20(6):801-815
Examined verbal learning and memory in children with myelomeningocele using the California Verbal Learning Test (CVLT). Participants included 41 children with myelomeningocele, 8 to 15 years of age, 33 of whom had a history of shunted hydrocephalus, and 41 matched, unaffected controls. Children with myelomeningocele and shunted hydrocephalus performed worse than controls on the CVLT. They recalled as many words as controls on the first learning trial, but acquired words more slowly across trials, so that their overall recall was lower. Their learning was characterized by a pronounced recency effect. Their delayed recall of the original list was worse than controls, but not their recognition. Performance of children with myelomeningocele but without shunts was generally not significantly different from that of the other two groups, although they did demonstrate better long-delay free recall than children with shunts. Myelomeningocele is associated with significant retrieval problems when accompanied by shunted hydrocephalus. 相似文献
70.
1. To test the hypothesis that protein kinase C (PKC) is involved in the inhibitory actions of lipoxin A4 (LXA4) on second messenger generation, we studied the effects of LXA4 on PKC in human neutrophils and on leukotriene B4 (LTB4)-stimulated inositol-1,4,5-trisphosphate (Ins(1,4,5)P3) generation. 2. LXA4, 1 microM, caused a fall in cytosolic PKC-dependent histone phosphorylating activity to 23.5% of basal levels. 3. LXA4, caused an increase in particulate PKC-dependent histone phosphorylating activity with a bell-shaped dose-response fashion; maximal stimulation was observed at 10 nM LXA4. 4. Western blot analysis with affinity-purified antibodies to alpha- and beta-PKC showed that only the beta-PKC isotype was translocated by LXA4. 5. LXA4 inhibited LTB4-stimulated Ins(1,4,5)P3 generation in a bell-shaped fashion with maximal inhibition at 1 nM LXA4. The observed inhibition was dose-dependently removed by pre-incubation with a PKC inhibitor (Ro-31-8220). 6. These results show that LXA4 activates PKC in whole cells and supports a role for PKC activation in the inhibitory action of LXA4 on LTB4-induced Ins(1,4,5)P3 generation. 7. LXA4 (1-1000 nM) pre-incubation did not affect specific binding of [3H]-LTB4 to neutrophils. Thus, the inhibitory effect of LXA4 on LTB4-stimulated Ins(1,4,5)P3 generation could not be attributed to an effect on LTB4 receptors. 相似文献