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Several species of the genus Haemophilus are well known etiological agents of pneumonia, meningitis, conjunctivitis, epiglottitis and chancroid. However, identification and speciation of Haemophilus is both time consuming and labor intensive. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF-MS) has been used by several investigators to profile proteins from intact and disrupted bacteria; consequently, MALDI/TOF-MS has emerged as a powerful tool in diagnostic bacteriology. This paper reports the use of MALDI/TOF-MS as a technique for the rapid identification and speciation of Haemophilus. This technique was used to not only identify the pathogen, H. ducreyi, but also to determine strain differences from different isolates. Mass spectral 'fingerprints' were obtained which permitted the rapid speciation of not only pathogenic forms of Haemophilus, but also those bacteria which are normally regarded as non-pathogenic and members of the normal flora. MALDI/TOF mass spectra can be acquired in 10 min, allowing the identification of Haemophilus spp. within 24 h rather than the 48 h or more needed for traditional bacteriological methods. In addition, these are the first mass spectral fingerprints available in the literature for many of these organisms. 相似文献
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OBJECTIVE: We tested the hypothesis that nitric oxide synthesis by the kidney is increased in children with primary nephrotic syndrome. METHODS: We examined the urinary excretion of nitrite, a stable metabolite of nitric oxide, using the Griess reaction, in children with nephrotic syndrome. RESULTS: In comparison with healthy children, patients with minimal change nephrotic syndrome had increased urinary nitrite excretion regardless of whether the disease was in relapse or remission (p < 0.025). In contrast, urinary nitrite excretion was similar in control subjects and patients with focal segmental glomerulosclerosis or IgA nephropathy. CONCLUSION: These findings indicate that measurement of urinary nitrite excretion may be a useful test to help discriminate between minimal change nephrotic syndrome and focal segmental glomerulosclerosis in children with idiopathic nephrotic syndrome. 相似文献
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WH Sheu SM Shieh DD Shen MM Fuh CY Jeng YD Chen GM Reaven 《Canadian Metallurgical Quarterly》1994,127(2):331-336
Treatment of patients with type IIA hyperlipoproteinemia (HLP) with pravastatin for 3 months led to significant decreases (p < 0.001) in total cholesterol (7.18 +/- 0.30 to 5.75 +/- 0.30 mmol/L), LDL cholesterol (5.56 +/- 0.33 to 4.02 +/- 0.32 mmol/L), and ratio of total cholesterol to HDL cholesterol (6.5 +/- 0.4 to 4.6 +/- 0.4). Decreases of a similar magnitude were also seen in patients with type IIB HLP. Plasma glucose and insulin concentrations after an oral glucose load and from 8 AM to 4PM in response to meals were higher in patients with Type IIB HLP, who also had higher steady-state plasma glucose concentrations after an infusion of somatostatin, insulin, and glucose (12.4 +/- 1 vs 5.5 +/- 0.8 mmol/L, p < 0.001). Because steady-state plasma insulin concentrations were similar in both groups, patients with type IIB HLP were relatively insulin resistant. Furthermore, day-long plasma glucose concentrations and insulin resistance were modestly, but significantly (p < 0.01), greater after treatment in both groups. In conclusion, LDL cholesterol metabolism improved in hypercholesterolemic subjects treated with pravastatin, but the hypertriglyceridemia, insulin resistance, relative glucose intolerance, and hyperinsulinemia present in patients with type IIB HLP either did not improve with treatment or was somewhat worse. 相似文献
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The objective of this study was to assess the relationship between amniotic fluid volume (AFV) and fetal movements at < 32 weeks gestation as assessed by routine biophysical profile (BPP). From a database of 465 consecutive nonhypertensive, nondiabetic patients delivering at < 32 weeks gestation, patients with singleton, nonanomalous fetuses with AFV and fetal movements determined as part of a BPP assessment within 24 hours of delivery were studied. Amniotic fluid volume was scored 0 to 2, according to the following criteria: largest pocket in vertical diameter < 1 cm = 0; < 2 but > 1 cm = 1; > or = 2 cm = 2. Fetal movements (FM) were scored over 30 minutes: 0 if absent, 1 if 1 to 2 movements, 2 if > or = 3 gross (limb/trunk) movements. Variables assessed included fetal presentation, gestational age (GA), premature rupture of membranes (PROM) as a principal indication for delivery, clinical chorioamnionitis (diagnosed by previously published criteria), histologic parameters of infection (in amnion and umbilical cord assessed by a single pathologist blinded to clinical data), and neonatal outcome. Statistical analyses included contingency tables and analysis of variance with p < 0.05 considered significant. Three hundred and fifty-two patients met the inclusion criteria. One hundred and sixty-seven patients (47%) had PROM as a primary indication for delivery. Infrequently, decreased fetal well-being manifested by a BPP < 7 of 10 points was an indication for delivery despite prematurity (n = 7). Of the 352 patients, 80 (23%) had AFV = 0, 60 (17%) had AFV = 1, and 212 (60%) had AFV = 2; and 12 (3%) had FM = 0, 30 (9%) FM = 1, and 310 (88%) FM = 2. There was a significant correlation between decreased AFV and decreased fetal movements (p < 0.0001). Fetal presentation and GA were not significantly different between patients based on score of fetal movements. The incidence of clinical chorioamnionitis was significantly greater in patients with FM = 0 (p < 0.005). We conclude that decreased AFV is associated with decreased fetal movements irrespective of fetal presentation or gestational age. Neonatal outcome (umbilical vasculitis, sepsis, intraventricular hemorrhage) is affected only in unusual cases in which otherwise uncompromised (nonhypoxic, nonacidotic) fetuses have low scores on both these antepartum ultrasonographic parameters. 相似文献