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At least 991 records · Page 55Linked to original sources
PubMed2002

[Flash visual evoked potentials (FVEP) examination under midazolam sedation of non-cooperating children].

PURPOSE: To find the optimal conditions for visual evoked potential (VEP) examination of non-cooperative children using midazolam maleate sedation. PATIENTS: 32 children aged from 8 months to 13 years (mean 3.5 years) with mental disorders, emotional problems and/or very low vision due to various reasons. METHODS: VEP--flash and bright flash according to ISCEV standards. Midazolam maleate sedation 0.4-0.5 mg per kilo body weight, given orally. RESULTS: Only 6 children aged from 11 months to 3.5 years (mean 2.5 years) required sedation for VEP examination. Midazolam sedation unabled VEP examination, was safe for children and well-tolerated. CONCLUSION: Second degree sedation in Ramsey score is effective for good VEP examination of non-cooperative children.

Anxiety↗
PubMedDate not supplied

[Contact shot from infantry weapons with a flash-suppressor].

The number of reports on contact shots from firearms with a flash suppressor attached to the muzzle is small. On the basis of a case report (suicidal shot to the forehead with a Kalschnikow AKMS 47 assault rifle) the morphological peculiarities (characteristics soot pattern, relatively small powder cavity and only minor skin tears in the presence of a bony support) are presented and the conclusions to be drawn from the findings regarding the flash-suppressor, the shot distance, the angle of the shot and the way of holding the weapon are discussed.

Adult↗
PubMed1992

[Differentiation between hepatoma and hemangioma by inversion recovery snapshot FLASH MR imaging with variable TIs].

To differentiate hepatoma from hemangioma, MR studies were performed for 18 patients with 21 untreated liver tumors (hepatoma 10, hemangioma 11). We obtained inversion recovery snapshot FLASH images of liver tumors with variable TIs (50, 100, 150, 200, 250, 300, 400, and 500 msec). 8 hemangiomas showed higher intensity than liver parenchyma on the images at 150 msec and less of TI, and lower intensity at 200 msec or more TI. In 7, signal intensity of hepatoma became low at 150 msec or less of TI or remained high with prolonged TI. Inversion recovery snapshot FLASH imaging with variable TIs will be useful for differentiating between hepatoma and hemangioma.

Adult↗
PubMed1992

[Changes in spontaneous slow potentials and visually (flash) evoked potentials in response to stimuli with no performance implication].

The influence of spontaneous slow potential shifts (SPSs) on visual (flash-)evoked potentials (VEPs) was studied. Eighteen subjects received 100 flashes. The sequence of interstimulus-intervals (ISIs) was pseudo-randomized. ISI-durations were 3, 5, 7, 9 or 11 seconds. EEG was recorded from Fz, Cz, Pz and Oz with linked-mastoids as reference. EEG was EOG-corrected and VEPs were calculated for preceding positive SPSs. Averaging was done for local SPSs; VEP pairings as well as VEPs were calculated over occipital SPS-polarities. Results showed an influence of SPSs on VEP-amplitudes. Differences in amplitudes were interpreted with the 'activation-correction'-hypothesis and with the 'ceiling'-hypothesis. Negative SPSs were followed by smaller negative peaks, and positive SPSs were followed by smaller positive peak-amplitudes. Differences in latencies of N145-P300 peak-to-peak amplitudes after SPSs of different polarity were explained with the threshold-regulation hypothesis. Spectral-analysis were done for SPS-data. There were only poor effects, showing increased parietal alpha 2-power after negative SPSs.

Adult↗
PubMed1992

[Evaluation of cerebral blood circulation using fast magnetic resonance imaging (turbo-FLASH)].

In its initial stage of development, poor time resolution was supposed to be inevitable for magnetic resonance imaging (MRI). The development of the gradient echo technique, however, has made an opening for a breakthrough to a fast MRI technique. However, conventional gradient echo technique is not fast enough to disclose the cerebral blood circulation. A new technique (turbo-FLASH), which combines gradient echo and preparation pulse, has opened the door to a true dynamic (high time resolution) MRI. The authors performed a basic study of this new fast imaging technique (Turbo-FLASH) for the evaluation of cerebral blood circulation. Using this dynamic MRI, the conventional Gd-DTPA administration (0.1mmol/kg, intravenous manual administration) has produced sufficient contrast to reveal a difference of the extent of enhancement between normal gray matter and white matter. In patients of cerebral infarction, the infarcted brain does not show any significant increase of signal intensity after the administration of contrast medium, whereas the normal brain shows a sharp increase of signal intensity after the administration of contrast medium. Indeed, many puzzling questions remain to be solved for clinical application of this new dynamic MRI. For example, the optimal quantity of contrast medium and optimal parameters for this sequence (T1 weighted or T2 weighted?) are still unknown. But, in any case, this dynamic MRI is expected to be a clinically powerful tool for the evaluation of cerebral blood flow.

Brain↗
PubMed1992

Differential diagnosis of adrenal masses using out-of-phase FLASH imaging. A preliminary report.

The purpose of this report was to suggest the ability to differentiate adrenal masses by out-of-phase FLASH imaging. The images were obtained with breath-holding at TR/TE 100/12 ms, flip angle 20 degrees. The material included adrenal adenoma (n = 16), nodular hyperplasia (n = 1), pheochromocytoma (n = 5), and adrenal metastatic tumors (n = 7). The signal intensity ratios of the adrenal mass/the diaphragmatic crus, back muscle, and renal cortex were obtained. The mean values of the ratios of adenomas or nodular hyperplasia were significantly different from pheochromocytomas or metastases. Although the number of adrenal masses was fairly small, the ratios of adrenal mass/diaphragmatic crus could distinguish them with no overlapping case. All 17 masses with the ratio of 1.16 or less were adenomas or nodular hyperplasia, whereas all 12 masses with a ratio greater than 1.23 were pheochromocytomas or metastases. This result suggests the ability of out-of-phase FLASH imaging to differentiate adrenal masses.

Adrenal Gland Neoplasms↗
PubMed2006

Bilateral renal artery stenosis presenting as flash pulmonary edema.

Flash pulmonary edema is a condition characterized by sudden and recurrent episodes of dyspnea at rest resulting from acute pulmonary venous congestion in the presence of normal or well-preserved LV systolic function. This is usually associated with bilateral renal artery stenosis or stenosis of a single surviving kidney. We report here a case of a 58-year-old man, a patient of coronary artery disease who later developed bilateral renal artery stenosis and presented with recurrent episodes of flash pulmonary edema. He was successfully treated with stenting of both renal arteries.

Angioplasty, Balloon↗
PubMedDate not supplied

[The application of PS II model for the analysis of fluorescence yield transients induced by actinic single turnover flash in the time range from 100 ns to 10 s].

Changes in flash-induced fluorescence yield in preparations of thermophilic Chlorella pyrenoidosa Chick cells (native and in the presence of DCMU) were investigated in the time range from 100 ns to 10 s using a new measuring system. The results were analyzed by mathematical modeling of processes in photosystem II. It was shown that the detailed description of recombination (including nonradiative) processes in photosystem II is important to simulate the fluorescence yield transients induced by an actinic single turnover flash. The model photosystem II parameters were modified to describe the light-induced effects in the presence of DCMU. By comparing the theoretical fluorescence curves with experimental ones, we obtained the values of relative fluorescence yield and the FM/F0 ratio, which is typical for experimental data. As a result of simulation, the values of the model parameters (rate constants of electron transfers at the donor and acceptor sites of photosystem II, pH in stroma, initial redox state of the plastoquinone pool, the rate of plastoquinol oxidation, and the rate constants of nonradiative recombination processes) were determined.

Chlorella↗
PubMed1991

[An apparatus for automated control of exposure in microphotography using a photo flash].

The authors suggest a device for automated exposure in micro-photographing with the use of the Elektronika B5-22 flash light. This pulsed light source is optimal as regards its spectral composition. The gist of the method is as follows: the flash photographic element, built in a light-proof case, disposed on the microscope ocular, permits governing the light pulse length.

Lighting↗
PubMed1991

The controversy of flash sterilization.

1. Flash sterilization is only recommended for emergency situations because the speed of the process reduces the margin of safety, increases the possibility of trapped air, and requires a high degree of reliability in the sterilizer. 2. When the weight of the instruments is increased, a greater number of organisms may be present and the heat up time of the sterilizer cycle will be longer. 3. If flash sterilization is used, it is important to know the parameters of the unit, how to use it, and how to transport the items so that they are protected from potential air-borne contaminants.

Emergencies↗
PubMed1991

Relationship of oscillatory potential amplitude to A-wave slope over a range of flash luminances in normal subjects.

The effect of flash luminance on the relationship of oscillatory potential (OP) amplitude, as a measurement of inner retinal function, to a-wave slope, as a measurement of photoreceptor function, was evaluated in full-field electroretinograms recorded from normal subjects. The ratio of OP amplitude to a-wave slope was found to be independent of flash luminance over a 3000-fold luminance range. This finding raises the possibility that a reduction in the ratio of OP amplitude to a-wave slope in eyes with media opacities may be used as a sign of inner retinal malfunction. Selected cases are presented to illustrate application of this approach.

Adult↗
PubMed1991

The influence of age on the pattern and flash visual evoked magnetic response (VEMR).

The visual evoked magnetic response (VEMR) was measured over the occipital cortex to pattern and flash stimuli in 86 normal subjects aged 15-86 years. The latency of the major positive component (outgoing magnetic field) to the pattern reversal stimulus (P100M) increased with age, particularly after 55 years, while the amplitude of the P100M decreased more gradually over the lifespan. By contrast, the latency of the major positive component to the flash stimulus (P2M) increased more slowly with age after about 50 years, while its amplitude may have decreased in only a proportion of the elderly subjects. The changes in the P100M with age may reflect senile changes in the eye and optic nerve, e.g. senile miosis, degenerative changes in the retina or geniculostriate deficits. The P2M may be more susceptible to senile changes in the visual cortex. The data suggest that the contrast channels of visual information processing deteriorate more rapidly with age than the luminance channels.

Adolescent↗
PubMed1991

Bio-flash chromatography--rapid, low-cost purification of peptides.

The use of wide pore 40/60 mu Sorbsil silicas bonded with a range of biocompatible phases now allows the biochemist to benefit from the advantages that flash chromatography has given to synthetic organic chemists. The technique of bio-flash chromatography allows rapid peptide and protein purification at low pressure (less than 15 psi) and at a fraction of the cost of high-pressure systems.

Bacitracin↗
PubMedDate not supplied

Macular dazzling test in central serous retinopathy using electronic flash.

Recovery time after dazzling the macula by conventional electronic flash used by the photographer instead of the light of an ophthalmoscope was recorded in 100 normal subjects and 50 cases of active central serous retinopathy. In normal subjects the recovery time after macular dazzling test was 10 to 54 seconds. There was no difference in value between the two sexes. The recovery value increases with the advancement of age. The recovery time was 10 to 15 minutes in cases of active central serous retinopathy and there was no delay in recovery time in healed central serous retinopathy. The values elicited by electronic flash were repeatable in comparison to the technique of dazzling the macula by light of an ophthalmoscope.

Adolescent↗
PubMed1985

[Effect of flash chemoprophylaxis by cefotaxime on the appearance of postoperative bacterial superinfections in surgery of the prostate].

The effect on bacteriologically documented postoperative infection of flash prophylaxis using two intravenous injections of 20 mg/kg cefotaxime each was evaluated in a double blind, randomized trial against placebo. 181 participants free of urinary tract infection prior to surgery had either transurethral prostatic resection (TUR) (n = 90) or open prostatectomy (OP) (n = 91). Urine samples, blood samples, prostate specimens and skin swabs were investigated for pathogens. Rate of urinary tract infection was significantly reduced by cefotaxime (CTX) prophylaxis in both groups. CTX lowered the incidence of early postoperative urinary tract infection from 30% to 4% in TURs and from 46% to 4.5% in OPs. Similarly, a significant difference was demonstrated for incidences of intra and postoperative bacteremia. In open prostatectomy patients, a reduced rate of wound infection and shorter hospital stay were noted in the treated group. Pathogens recovered in this study were Streptococcus (29%), Staphylococcus (20.5%), Enterobacteriaceae (45.75%), Pseudomonas (1.25%), Acinetobacter (3%), and Bacteroides fragilis (0.5%). CTX prophylaxis apparently has no bearing on postoperative emergence of resistant pathogens. Percentage of resistance to CTX in delayed postoperative infections was 33% in the control group and 35% in the treated group. We conclude that flash CTX prophylaxis in transurethral or open prostatectomy is of benefit in reducing morbidity and hospital costs.

Bacterial Infections↗
PubMedDate not supplied

[Analysis of the stability of rabbit visual cortex neuron spike responses to light flashes].

The stability of neuronal responses in the rabbit visual cortex to diffuse photic flashes presented in series with sufficiently long time intervals between them was studied in acute experiments. Three types of neuronal responses with different degree of stability were singled out. The stability was judged by the mean coefficient of correlation between post-stimulus histograms of spike activity. Negative correlations were found between the mean correlation coefficient and mean square deviations of latencies of primary and secondary activation and the pause in impulse activity in neuronal responses to a photic flash. Positive correlations between primary activation latencies and mean square deviations of other response parameters suggest a greater stability of responses with a short latency.

Action Potentials↗
PubMed1984

Pituitary hormones during the menopausal hot flash.

Eighteen postmenopausal women with severe hot flashes had continuous recordings of finger temperature and skin resistance as objective indexes of flushing episodes, and serial measurements of anterior pituitary hormones as indirect indexes of hypothalamic neurotransmitter activity. Significant increases of growth hormone, adrenocorticotropic hormone (ACTH), and luteinizing hormone (LH) occurred with maximal concentrations at 30, five, and 15 minutes, respectively, after the onset of the skin temperature rises. No significant fluctuations of prolactin (PRL), thyroid-stimulating hormone (TSH), or follicle-stimulating hormone (FSH) were observed. The mean serum cortisol concentration increased 15 minutes after the hot flash, presumably consequent to the preceding elevation of ACTH. Pituitary ACTH release may be secondary to hypothalamic cooling, whereas increased growth hormone and LH output and the thermoregulatory adjustments comprising the flushing episodes are all consistent with cyclic episodes of increased hypothalamic norepinephrine activity.

Adrenocorticotropic Hormone↗