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111.
D. Passàli L. Bellussi M. Lauriello D. Passali 《European archives of oto-rhino-laryngology》1995,252(6):348-352
In this paper we have analyzed the physical properties of nasal mucus from 120 outpatients with rhinitis. We focused on the most relevant rheological features: viscosity, elasticity, adhesiveness, as well as ability to be spun (spinability) or poured (pourability). A double-capillary type viscometer was used to measure viscosity and elasticity and the platinum ring method to measure adhesiveness. Spinability was measured with an automatic apparatus (Filancemetre Sefam) and pourability was determined by describing flow under gravity. Efficacy of nasal clearance was analyzed by measuring mucociliary transport time with an inert tracer using vegetal charcoal powder. Results showed that impaired nasal mucosal function in patients with rhinitis could be determined by studying rheological features in addition to measuring mucociliary activity. Information provided proved invaluable when considering possible treatment with agents affecting kinesis of nasal mucus. 相似文献
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113.
Proton magnetic resonance spectroscopy pattern of progressive multifocal leukoencephalopathy in AIDS 总被引:3,自引:0,他引:3
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Iranzo A Moreno A Pujol J Martí-Fàbregas J Domingo P Molet J Ris J Cadafalch J 《Journal of neurology, neurosurgery, and psychiatry》1999,66(4):520-523
The objective was to determine whether the use of intermediate echo times (135 ms) in proton magnetic resonance spectroscopy (1H-MRS) detects a homogenous pattern in progressive multifocal leukoencephalopathy (PML) in HIV-1 infected people, and to confirm the results of previous studies. Six patients infected with HIV-1, with PML established by biopsy, and six healthy age and sex matched volunteers were evaluated to define their spectroscopic pattern. 1H-MRS spectra performed at 1.5 T were obtained with the STEAM sequence: TE/TM/TR, 20 ms/13.7 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (STEAM-20) and with the PRESS sequence; TE/TR, 135 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (PRESS-135). A single voxel was placed on the lesions and on the parieto-occipital white matter of controls. The peaks of N-acetylaspartate (NAA), choline (Cho), myoinositol (mI), lactate, and lipids were considered, and the results were expressed using creatine as reference. Spectra of PML lesions were characterised by significantly reduced NAA, lactate presence, and by significantly increased Cho and lipids compared with control group values. These results indicate that 1H-MRS detects a homogenous pattern in PML lesions. Recent studies, together with this, suggest that 1H-MRS may help in the diagnostic approach to patients with suspected PML lesions associated with AIDS. 相似文献
114.
Marosi E Rodríguez H Harmony T Yañez G Rodrìguez M Bernal J Fernàndez T Silva J Reyes A Guerrero V 《The International journal of neuroscience》1999,97(1-2):17-27
The relationship of IQ (measured by WAIS and all its subscales) and EEG broad band spectral parameters were studied in 40 right-handed, male volunteers ranging in age from 20 to 25 years old. EEGs were recorded in 20 derivations during rest with eyes opened. The results obtained reveal positive and negative correlations with abundant frontal participation in all bands. Mean frequency data show a frequency shift in a very narrow range suggesting that more relations in narrow band could be achieved. These results highlight the need of psychological tests that measure more homogeneous abilities and finer measurement technique to reveal clearly explainable correlations and demonstrate that EEG recordings do reflect intellectual abilities. 相似文献
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117.
D Pubill A M Canudas M Pallàs F X Sureda E Escubedo A Camins J Camarasa 《The Journal of pharmacy and pharmacology》1999,51(3):307-312
The peripheral adrenergic effects of orphenadrine, an antiparkinsonian drug, have been evaluated in the rat vas deferens to investigate whether these properties are the same as those of other phencyclidine ligands. In the low micromolar range, orphenadrine enhanced electrically-evoked and exogenous noradrenaline contractile responses in the epididymal portion of rat vas deferens. It also induced spontaneous activity that was inhibited by prazosin (1 microM) but not by atropine (20 nM). It inhibited accumulation of [3H]noradrenaline in rat vas deferens (IC50 = 14.2+/-2.3 microM). Orphenadrine competitively inhibited [3H]nisoxetine binding in rat vas deferens membranes (Ki = 1.05+/-0.20 microM). It can be concluded that orphenadrine, at low micromolar concentrations, interacts with the noradrenaline reuptake system inhibiting its functionality and thus potentiating the effect of noradrenaline. 相似文献
118.
Sànchez-Lamar A Fiore M Cundari E Ricordy R Cozzi R De Salvia R 《Toxicology and applied pharmacology》1999,161(3):231-239
The present work evaluates the cytotoxic, genotoxic, and antimutagenic effects of Phyllanthus orbicularis (plant of genus Phyllantus) aqueous extract in Chinese hamster ovary (CHO) cells. P. orbicularis aqueous extracts are used in Cuban traditional medicine for their antiviral activity against Hepatitis B virus and A and B flu virus. The cytotoxicity of the extract was tested by means of colony-forming ability and growth-inhibition assays as well as by measuring the mitotic index. Apoptosis induction and cell-cycle kinetics were analyzed by cytofluorimetric methods. Chromosome aberration assays were performed to study the genotoxic and antimutagenic activity of the extract. Results show that doses of up to 100 microg/ml of the extract did not induce any cytotoxic effects. Cell survival and mitotic index decreased significantly at doses higher than 100 microg/ml as a function of dose as well as of treatment time. Moreover, continuous treatments of up to 18 h induced the appearance of a significant number of apoptotic cells. Following a 3-h exposure to a dose of 750 microg/ml, cells accumulated significantly in G(2)-M phase and remained blocked in G(1-) and G(2)-M phases after several posttreatments in fresh growth medium. The aqueous extract alone did not induce chromosome aberrations but, in combined treatment with H(2)O(2), significantly reduced H(2)O(2)-induced chromosome aberrations. Flow cytometric analysis of DCFH intracellular oxidation showed that the extract decreased the oxidizing power of H(2)O(2.) This ability could possibly explain the extract's antigenotoxic activity. Absence of cytotoxicity at the lower tested doses and the antimutagenic properties of the extract stimulate the interest in studying possible new pharmaceutical uses of P. orbicularis. 相似文献
119.
A. Focà G. Matera M. C. Berlinghieri 《European journal of clinical microbiology & infectious diseases》1993,12(12):940-944
Antibiotic-induced endotoxin (lipopolysaccharide; LPS) release may precipitate septic shock. In the present study the effect of teicoplanin, which has been reported to neutralize LPS in experimental models, on LPS neutralization was investigated in human whole blood samples. Levels of interleukin 8, a proinflammatory cytokine which was stimulated bySalmonella minnesota R595 LPS (12.6 µg/ml), were monitored over time. Interleukin 8 concentrations increased over time up to 24 h. When LPS was preincubated with teicoplanin (antibiotic: LPS ratio 20:1, w/w), interleukin 8 concentrations were found significantly (p<0.05) reduced at 4, 8 and 24 h after LPS challange. Interleukin 1 (at 4, 8 and 24 h) and tumor necrosis factor (at 8 and 24 h) levels were also significantly decreased by teicoplanin. In this experiment model, a teicoplanin: LPS ratio 100-fold less than the ratio achievable in plasma of septic shock patients was able to reduce interleukin 8, which has been correlated with the severity of septic disease. 相似文献
120.
E Riva R Latini A Cremonesi F Zacà P Pagliarani 《Journal of cardiovascular pharmacology》1980,2(6):707-714
We studied the time course of three electrophysiologic effects of propranolol after intravenous and oral administration and their relationship with plasma levels within the same subjects. Ten patients who had undergone cardiac catheterization for diagnostic purposes received 0.1 mg/kg of propranolol intravenously. Blood was drawn at intervals for 12 hr and heart rate and the effective refractory periods of the atrium (ERPA) and the atrioventricular node (ERPAVN) were determined at the same time. Eight patients continued treatment with propranolol by the oral route for up to 4 days (40 mg every 12 hr). Blood was sampled after each morning dose. Plasma concentrations of propranolol were measured by gas chromatography. Maximal lengthening of ERPA after propranolol (15.1% i.v. and 9.4% oral) was much less marked than that of ERPAVN (23.2% i.v. and 19.4% oral). Heart rate decreased 23.5% (i.v.) and 13.1% (oral). Effects were seen much sooner after intravenous (5-8 min) than after oral administration (86-146 min), but they lasted about twice as long after oral as after intravenous treatment. 相似文献