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排序方式: 共有493条查询结果,搜索用时 250 毫秒
1.
1. Dibekacin (70 microM-3 mM) produced a decrease of peak tetanic tension in a concentration-dependent manner and this effect was dependent on extracellular calcium (0.3-2.5 mM Ca2+). Only minimal fade was observed and it was not related with extracellular calcium concentrations. 2. Diltiazem (30-300 microM) decreased peak tetanic tension and produced tetanic fade. Both effects were independent of extracellular calcium, although a significant potentiation was observed at 0.3 mM calcium. 3. It is concluded that tetanic parameters are related differently to extracellular calcium. 相似文献
2.
Kenneth P Wright Jr. Pietro Badia Bryan L Myers Steven C Plenzler Milton Hakel 《Brain research》1997,747(1):654
The effects of caffeine ingestion and exposure to bright light, both separately and in combination, on salivary melatonin and tympanic temperature were assessed in humans. Four treatments during a 45.5 h sleep deprivation period were compared: Dim Light-Placebo, Dim Light-Caffeine, Bright Light-Placebo and Bright-Light Caffeine. The Dim Light-Caffeine condition (200 mg twice each night) relative to the Dim Light-Placebo condition suppressed nighttime melatonin levels and attenuated the normal decrease in temperature. Combining caffeine ingestion with bright light exposure (≥2000 lux) suppressed melatonin and attenuated the normal nighttime drop in temperature to a larger degree than either condition alone; i.e. effects were additive. Circadian effects were also observed in that the amplitude and phase of the temperature rhythm were altered during treatment. These findings establish that the human melatonin system is responsive to caffeine. Other evidence suggests that caffeine may influence melatonin and temperature levels through antagonism of the neuromodulator adenosine. 相似文献
3.
S Ferré T Guix J Sallés A Badia P Parra F Jané M Herrera-Marschitz U Ungerstedt M Casas 《European journal of pharmacology》1990,179(3):295-299
We present evidence showing that paraxanthine (1,7-dimethylxanthine), the main metabolite of caffeine in man, displaces the binding of [3H]SCH 23390, a radioligand which selectively labels dopamine D-1 receptors when used at low concentrations, from striatal membranes of the rat. The displacement was competitive and indicated the existence of two affinity states (Hill coefficient = 0.49; K(high) = 0.15 microM; K(low) = 95.9 microM, %R(high) = 32.4). When the stable GTP analog Gpp(NH)p was included, the displacement curve indicated the presence of only the low-affinity state (Hill coefficient = 1.16; Ki = 72.1 microM). However, paraxanthine did not displace the specific binding of [3H]spiperone. After injection of 30 mg/kg s.c. of caffeine, a maximum of 10 microM of paraxanthine was found in striatal homogenates, which could be sufficient to occupy dopamine D-1 receptors. Our results suggest that a dopaminergic action of paraxanthine could be involved in the behavioural stimulation produced by caffeine. 相似文献
4.
Responsiveness to olfactory stimuli presented in sleep 总被引:1,自引:0,他引:1
Whether humans react to olfactory stimuli presented in sleep was assessed. Responses of ten participants (mean age = 22.8 years) were recorded to repeated three-minute periods of either air alone or to a peppermint odor (0.26 mg/liter) during stage 2 sleep. These responses included behavioral (awakening, microswitch closure), autonomic (heart rate, EMG, respiration), and central (EEG) components. An odor delivery system is described comprised of an aquarium pump, Teflon and TYGON tubing, oxygen mask, filtering, and air flow valves. The data indicate that humans react behaviorally, autonomically and centrally to olfactory stimuli presented while sleeping. Although the percentage of overall responsivity to olfactory stimuli was low, significant differences (ANOVA) in responsivity to odor periods vs. nonodor periods were found for microswitch closures, EEG, EMG, and heart rate. For these measures eight or more of the ten participants showed this pattern of differential responsivity during odor and nonodor periods (Sign test = p less than 0.05). A time-of-night effect was also observed in that responsivity tended to be greatest early in the night. The effect on responsivity of other durations, concentrations, and odors requires additional research. 相似文献
5.
Pietro Badia John Harsh Joel Culpepper Joseph Shaffer 《Journal of behavioral medicine》1988,11(6):585-592
Behavioral control of abnormal breathing in sleep was studied to determine if an intervention procedure could reduce apnea duration and also SaO
2
(blood oxygen) desaturation levels. Sleep apnea patients (n=11) were instructed while awake that tones would be presented in sleep whenever an apnea event occurred. They were told to breathe deeply to the tones and were given practice in doing so. Intervention and nonintervention hours alternated across 2 nights following 2 baseline nights. As expected, during the intervention hours, the duration but not the frequency of apneic events was reduced. The procedure also resulted in higher SaO
2
levels during the intervention hours. Daytime sleepiness was not greater following intervention but sleep staging effects were observed. The results are sufficiently promising to warrant additional research.This research was supported by NIH Grants 2 HL 27149-84 and HL 34125 entitled Behavioral Control of Respiration in Sleep. 相似文献
6.
M. Dolores del Toro López Javier Arias Díaz José M. Balibrea Natividad Benito Andrés Canut Blasco Erika Esteve Juan Pablo Horcajada Juan Diego Ruiz Mesa Alba Manuel Vázquez Cristóbal Muñoz Casares Jose Luis del Pozo Miquel Pujol Melchor Riera Jaime Jimeno Inés Rubio Pérez Jaime Ruiz-Tovar Polo Alejandro Serrablo Alex Soriano Josep M. Badia 《Cirugía espa?ola》2021,99(1):11-26
Antibiotic prophylaxis in surgery is one of the most effective measures for preventing surgical site infection, although its use is frequently inadequate and may even increase the risk of infection, toxicities and antimicrobial resistance. As a result of advances in surgical techniques and the emergence of multidrug-resistant organisms, the current guidelines for prophylaxis need to be revised.The Sociedad Española de Enfermedades Infecciosas (Spanish Society of Infectious Diseases and Clinical Microbiology) (SEIMC) together with the Asociación Española de Cirujanos (Spanish Association of Surgeons) (AEC) have revised and updated the recommendations for antibiotic prophylaxis in surgery to adapt them to any type of surgical intervention and to current epidemiology. This document gathers together the recommendations on antimicrobial prophylaxis in the various procedures, with doses, duration, prophylaxis in special patient groups, and in epidemiological settings of multidrug resistance to facilitate standardized management and the safe, effective and rational use of antibiotics in elective surgery. 相似文献
7.
Rohit R. Badia Solomon Woldu Hiten D. Patel Nirmish Singla Arnav Srivastava Joseph G. Cheaib Phillip M. Pierorazio Aditya Bagrodia 《Urologic oncology》2021,39(2):136.e19-136.e25
BackgroundThe American Joint Committee on Cancer 8th edition staging guidelines for testicular cancer established a 3 cm cutoff to subclassify stage T1 seminomas (<3 cm = pT1a and ≥3 cm = pT1b). The efficacy of this cutoff in predicting metastatic disease and impact on treatment patterns have not been studied.MethodsWe retrospectively reviewed patients with pT1 testicular seminoma in the National Cancer Database from 2004 to 2016. Receiver operating curves were used to determine the efficacy of the 3 cm tumor cutoff in identifying metastatic disease, and multivariable regression was used to compute the effect of tumor size on the rate of adjuvant therapy among Stage I patients.ResultsA total of 10,134 patients with pT1 seminoma were evaluated. The current size cutoff of 3 cm for subclassification did not exhibit high discrimination in identifying metastatic disease (area under receiver operating curve: 0.546). Surveillance has grown as the preferred treatment after orchiectomy ?32.1% in 2004 to 81.2% in 2015. However, the rate of adjuvant therapy for pT1, Stage I seminomas associated positively with tumor size even with adjustment for year of diagnosis. For tumors above 3 cm, the odds ratio stabilized around 1.9. By using the 3 cm cutoff to guide adjuvant therapy, up to 85% of T1b patients may be overtreated.ConclusionThe 3 cm cutoff for subclassification of Stage I seminoma does not predict metastatic recurrence but is associated with increased receipt of adjuvant therapy. A 3 cm cutoff and the pT1a/b classification may therefore contribute to overtreatment in many young patients with a long life expectancy for whom minimizing adverse effects should be prioritized. 相似文献
8.
E. Vila J. Sallés A. Badia 《Journal of neural transmission (Vienna, Austria : 1996)》1990,82(3):205-212
Summary The effects of a single administration (48 hours) and of chronic (14 days) treatment with tricyclic (desipramine, nortryptiline) and nontricyclic (mianserin, nomifensine) antidepressant drugs on responses of the isolated anococcygeus muscle to the 2-adrenoceptor agonist xylazine (inhibition of contraction to field stimulation at 1 Hz) and to the 1-adrenoceptor agonist phenylephrine (contraction of the muscle) have been studied.Of the drugs used only desipramine and nortryptiline administered chronically reduced the responsiveness of the anococcygeus muscle to phenylephrine suggesting a desensitization of postsynaptic 1-adrenoceptors. Long-term but not acute administration of antidepressants resulted in significant decrease in sensitivity of presynaptic 2-adrenoceptors to xylazine. These results show that the adaptative changes of -adrenoceptors in the rat anococcygeus muscle following long-term administration may depend on the efficiency to inhibit the neuronal uptake and the ability to antagonize 1-adrenoceptors. 相似文献
9.
E. Fernandez A. Schiaffino L. Rajmil X. Badia A. Segura 《Journal of epidemiology and community health》1999,53(4):218-222
BACKGROUND AND OBJECTIVES: While socio-economically derived differences in health and health services use have long been a subject of study, differences based on gender, considered as the explicative variable, have scarcely been quantified from population-based data. The aim of this investigation was to analyse inequalities in health and health care services utilisation between men and women in Catalonia (Spain). DESIGN, SETTING, PARTICIPANTS, AND MEASURES: Data from the Catalan Health Interview Survey, a cross sectional survey conducted in 1994, were used. A total of 6604 women and 5641 men aged 15 years or over were included for analysis. Health related variables studied were self perceived health, restriction of activity (past two weeks), and presence of chronic conditions; health services use variables analysed were having visited a health professional (past two weeks), an optometrist (12 months), or a dentist (12 months); and hospitalisation (past 12 months). Age standardised proportions were computed according to gender, and prevalence odds ratios (OR) were derived from logistic regression equations. MAIN RESULTS: Women more frequently rated their health as fair or poor than men (29.8% v 21.4%; OR = 1.22; 95% CI: 1.10, 1.34). More women than men reported having restricted activity days (OR = 1.86; 95% CI: 1.59, 2.18) and chronic conditions (OR = 1.74; 95% CI: 1.60, 1.89). The proportion of women visiting a health professional was slightly greater than that for men (OR = 1.20; 95% CI: 1.09, 1.31), as was the proportion of women visiting an optometrist (OR = 1.21; 95% CI: 1.11, 1.33), and a dentist (OR = 1.43; 95% CI: 1.31, 1.55). The proportion of hospitalisation was lower in women (6.6%) than in men (7.7%; OR = 0.73; 95% CI: 0.63, 0.85). When health services use was analysed according to self perceived health, women declaring good health reported a greater probability of consulting a health professional (OR = 1.35; 95% CI: 1.20, 1.52). There were no differences in respect to hospitalisation, visits to the optometrist and to the dentist. CONCLUSIONS: These results indicate a pattern close to the inverse care law, as women, who express a lower level of health and thus would need more health care, are not, however, using health services more frequently than men. 相似文献
10.
Luchetti R Badia A Alfarano M Orbay J Indriago I Mustapha B 《The Journal of hand surgery, European volume》2000,25(1):38-40
From 1995 to 1998, 30 patients with dorsal wrist ganglia and four with recurrent dorsal ganglia underwent arthroscopic resection. At a mean follow-up of 16 months, no complications were seen, but minimal pain persisted in three patients. Two recurrences were seen after arthroscopic resection of primary ganglia. 相似文献