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991.
Identification and detection of Bacillus sporothermodurans spores in 1, 10, and 100 milliliters of raw milk by PCR 总被引:1,自引:0,他引:1
A PCR method was developed to detect spores of Bacillus sporothermodurans in 1, 10, and 100 ml of raw milk. Two primers were derived from a unique sequence after subtractive hybridization of B. sporothermodurans DNA with DNA of MB 397, a not yet identified spore-forming bacterium isolated from raw milk, closely related to B. sporothermodurans. Specific identification was proven on a large collection of Bacillus strains and on strains from relevant taxa. The detection of B. sporothermodurans in raw milk is based on activation, germination, and outgrowth of the spores, followed by PCR identification. Spores from 10 and 100 ml were concentrated by centrifugation after chemical extraction of the milk components. The total test takes 28 h. The detection limits are 9, 0.4, and 0.22 CFU/ml for 1, 10, and 100 ml, respectively. 相似文献
992.
In this study, the Health Promotion Model (HPM) was used as the basis for a structural equation model of male and female blue collar workers' self-reported use of hearing protection devices (HPDs). Overall use did not differ by gender; in addition, self-efficacy and barriers to use of HPDs were the two best predictors of this behavior for both men and women. Despite the similarities in HPD use and the most important predictors of that use between men and women, the predictive models differed by gender in several ways. Significant predictors of use among men also included age and value of use of HPDs. For women, ethnic status and plant site were additional significant predictors of use. Because the influences of plant site and gender on self-reported use of HPDs could not be separated in this study, further research should address worksite culture and assess differences by gender. Knowledge of these differences will aid development of more effective interventions and may increase the use of hearing protection. 相似文献
993.
994.
OBJECTIVES: Given the reported relationship between systolic hypertension and orthostatic hypotension in the elderly, to test the hypothesis that systolic hypertension causes impairment of the cardiovascular reflex function additional to the effects of age alone. DESIGN: Responses were compared in normotensive healthy young (n = 12) and elderly (n = 15) participants and elderly participants with disproportionate supine systolic hypertension (n = 11) using a baroreceptor-mediated stress (head-up tilt) and two non-baroreceptor-mediated stimuli (cold pressor test and isometric exercise). METHODS: Blood pressure and heart rate were measured by oscillometry before and during the three stress tests. Forearm blood flow was measured by venous occlusion plethysmography and pulse wave velocity (PWV) by Doppler ultrasound. RESULTS: Percentage changes in systolic/diastolic (SBP/DBP) blood pressure with head-up tilt were 0/+11, -3/0 and -6/+1 mmHg in the young and elderly normotensives and elderly systolic hypertensives, respectively. Both elderly groups had reduced DBP responses to tilt compared with the young (P < 0.01). All three groups had similar percentage changes in blood pressure responses to non-baroreflex-mediated stresses (cold pressor test: +10/+23, +11/+11, +10/+15; sustained isometric exercise: +18/+33, +22/+24, +13/+17 in the young and elderly normotensives and elderly systolic hypertensives, respectively). Aorto-iliac PWV adjusted for blood pressure was significantly higher in both elderly groups compared with the young (P < 0.01) but there was no difference between elderly normotensives and hypertensives. Unadjusted PWV was higher in elderly hypertensives than in elderly normotensives (P < 0.05). CONCLUSIONS: Compared with healthy young participants, both elderly groups had similarly attenuated blood pressure responses to tilt and reduced arterial compliance. Systolic hypertension is not associated with additional impairment of cardiovascular reflex function over and above the effects of age. The reported association between supine systolic hypertension and orthostatic hypotension does not appear to be a causative one. 相似文献
995.
Effects of color on emotions. 总被引:3,自引:0,他引:3
Emotional reactions to color hue, saturation, and brightness (Munsell color system and color chips) were investigated using the Pleasure-Arousal-Dominance emotion model. Saturation (S) and brightness (B) evidenced strong and consistent effects on emotions. Regression equations for standardized variables were: Pleasure?=?.69B?+?.22S, Arousal?=?-.31B?+?.60S, Dominance?=?-.76B?+?.32S. Brightness effects were nearly the same for chromatic and achromatic colors. Blue, blue-green, green, red-purple, purple, and purple-blue were the most pleasant hues, whereas yellow and green-yellow were the least pleasant. Green-yellow, blue-green, and green were the most arousing, whereas purple-blue and yellow-red were the least arousing. Green-yellow induced greater dominance than red-purple. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
TH Grasela CA Walawander M Beltangady CA Knupp RR Martin LM Dunkle RH Barbhaiya KA Pittman R Dolin FT Valentine 《Canadian Metallurgical Quarterly》1994,169(6):1250-1255
Phase I dose-escalating trials of didanosine revealed dose-limiting toxicities, including pancreatitis, and established a total daily dose of 12.5 mg/kg/day as the maximum tolerated dose. Clinical and pharmacokinetic data of 61 patients from two trials were analyzed to further evaluate the risk of pancreatitis: 1 (6.3%) of 16 patients who received < 500 mg/day didanosine, 2 (13.3%) of 15 who received 500-750 mg/day, and 15 (50%) of 30 who received > 750 mg/day developed pancreatitis (P < .001). A relationship between risk of pancreatitis and steady-state plasma concentrations of didanosine and age was also observed, suggesting that knowledge of didanosine pharmacokinetics provided additional information regarding risk of toxicity. Further confirmation of these findings will be necessary to determine if the risk factors for pancreatitis remain the same at lower doses currently used. 相似文献
997.
LM Helms JP Felix RM Bugianesi ML Garcia S Stevens RJ Leonard HG Knaus R Koch SG Wanner GJ Kaczorowski RS Slaughter 《Canadian Metallurgical Quarterly》1997,36(12):3737-3744
Voltage-gated potassium (K(V)) channels play key roles in setting the resting potential and in the activation cascade of human peripheral T lymphocytes. Margatoxin (MgTX), a 39-amino acid peptide from Centruroides margaritatus, is a potent inhibitor of lymphocyte K(V) channels. The binding of monoiodotyrosinyl margatoxin ([125I]MgTX) to plasma membranes prepared from either Jurkat cells, a human leukemic T cell line, or CHO cells stably transfected with the Shaker-type voltage-gated K+ channel, K(V)1.3, has been used to investigate the properties of lymphocyte K(V) channels. These data were compared with [125I]MgTX binding to heterotetrameric K(V) channels in rat brain synaptic plasma membranes [Knaus, H. G., et al. (1995) Biochemistry 34, 13627-13634]. The affinity for [125I]MgTX is 100-200 fM in either Jurkat or CHO/K(V)1.3 membranes, and the receptor density is 20-120 fmol/mg in Jurkat membranes or 1000 fmol/mg in CHO/K(V)1.3 membranes. In contrast to rat brain, [125I]MgTX binding to Jurkat and CHO/K(V)1.3 membranes exhibits an absolute requirement for K+, with no potentiation of binding by Na+. K(V)1.3 was the only K(V)1 series channel present in either CHO/K(V)1.3 or Jurkat plasma membranes as determined by immunoprecipitation of [125I]MgTX binding or by Western blot analyses using sequence-specific antibodies prepared against members of the K(V)1 family. The relative potencies of a series of peptidyl K(V) channel inhibitors was essentially the same for inhibition of [125I]MgTX binding to Jurkat, CHO, or rat brain membranes and for blocking 86Rb+ efflux from the CHO/K(V)1.3 cells, except that alpha-dendrotoxin was more potent at blocking binding to rat brain membranes than in the other assays. The characteristics of [125I]MgTX binding, the antibody profiles, and the effects of the peptidyl K(V) inhibitors all indicate that the [125I]MgTX receptor in Jurkat lymphocytes is comprised of a homomultimer of K(V)1.3, unlike the heteromultimeric arrangement of the receptor in rat brain. 相似文献
998.
LM Levasseur A Delon WR Greco P Faury S Bouquet W Couet 《Canadian Metallurgical Quarterly》1998,15(7):1069-1076
PURPOSE: A new mathematical approach was developed to quantify convulsant interaction between pefloxacin and theophylline in rats. METHODS: Animals received each compound separately or in different combination ratios. Infusion was stopped at the onset of maximal seizures. Cerebrospinal fluid (CSF) and plasma samples were collected for HPLC drug determination. The nature and intensity of the pharmacodynamic (PD) interaction between drugs was assessed with a new modeling approach which includes (a) data transformation to create an essentially error-free X-variable and (b) estimation of an interaction parameter a by fitting a nonlinear hyperbolic model to the combination data with unweighted nonlinear regression. RESULTS: Drug disposition to the biophase was linear within the range of administered doses. The estimates of a suggested a Loewe antagonistic interaction between pefloxacin and theophylline at the induction of maximal seizures in rats. Similar intensity of PD interaction was observed at the dose and biophase level (alpha was -0.415 +/- 0.069 and -0.567 +/- 0.079, respectively). CONCLUSIONS: The suitability of the proposed model was assessed by Monte Carlo simulation. This new mathematical approach enabled the characterization of the Loewe antagonistic nature of the PD (convulsant) interaction between pefloxacin and theophylline, whereas previously used methodologies failed to do so. 相似文献
999.
Sdo C Jorge DD Kormann P Medeiros JC Mateos MM Zamorano LM Silva MN Zambonini AS Arnoni JE Assef HM Magalh?es 《Canadian Metallurgical Quarterly》1994,62(4):243-246
Five patients who had permanent pacemaker and infective endocarditis were analyzed. Diagnose was confirmed by a positive blood cultures in all patients and 2 of them had identifiable vegetation in the echocardiogram too. The etiologic agent was Staphylococcus aureus in 3, Staphylococcus epidermidis in 1 and Staphylococcus viridans in 1. Three patients were treated with antibiotics alone: one had no clinical conditions to be operated, one died before surgery and one had good response to antimicrobial therapy alone. Two patients were submitted to antibiotic therapy and surgical removal of the pacemaker system, without complications. It was concluded that the surgical removal of the pacemaker system, as soon as possible, is the choice's therapy. 相似文献
1000.
Indigenous Indian groups comprise approximately 20% of Ecuador's population, the third largest percentage in all of Central or South America, yet immunogenetic data on these groups are lacking in the literature. In the course of population migration studies, sera collected from 65 Ecuadorians living in the northern province of Esmeraldas were typed for six GM and two KM markers. The study population consisted of 47 Cayapa Indians and 18 blacks of African origin, descendants of slaves imported into the area during the seventeenth century. The Cayapa demonstrated three GM phenotypes, two of which are common to other South American Indian tribes. The frequency of KM1 positive Cayapa Indians (63%) is similar to other South American Indian tribes, but is significantly greater than the Huaorani of eastern Ecuador (2%), the only other Ecuadorian Indian group for whom limited immunoglobulin allotype data are available (chi 2 = 35.8, P < 0.0001). 相似文献