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1.
OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources. 相似文献
2.
3.
Menahem Neuman Boris Friedman Avi Stein A. Ami Sidi Alexander Tsivian 《Gynecological surgery》2007,4(3):175-178
The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral
sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The
study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in
one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second
group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative
diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months.
The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly
younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration,
intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either
group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and
5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients
and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients,
while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of
the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT
procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective
in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than
previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures,
less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however,
had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions
can be drawn on the superiority of either of these two operative techniques. 相似文献
4.
Zahava Sololmon Shimon E. Spiro Arik Shalev Avi Bleich Samuel Cooper 《Journal of traumatic stress》1992,5(2):217-223
Nine months after the residential stage of Koach, participants were asked to evaluate the program's effectiveness. Most of the veterans reported improvement in the areas queried, and especially in social relations, and nearly all of them stated that they would recommend the program to other veterans. The commander-therapists became the major source of help for these veterans following the Koach project, and about half reported that they participated regularly in self-help groups. Most of the participants acquired coping techniques that continued to serve them 9 months after the end of the residential stage of Koach. One of the more important measures of Koach was thought to be the veterans' own evaluations of the project, their assessment of the project's success in achieving its aims, and their satisfaction with it. In this article we will present the subjects' evaluations of treatment effectiveness as expressed in behavioral and emotional changes that they attributed to the treatment. 相似文献
5.
Dual activity maps in primate visual cortex produced by different temporal patterns of zif268 mRNA and protein expression
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Avi Chaudhuri Jonathan Nissanov Sylvie Larocque Lise Rioux 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(6):2671-2675
The inducible nature of the immediate-early genes (IEGs) c-fos and zif268 allows their products to be used as activity markers in the brain. The utility of such markers in general is restricted because they can resolve only neurons activated by a single stimulus. To overcome this limitation, we have developed a double-label technique that exploits the dissimilar time course of zif268 mRNA and protein induction, allowing them to be separately induced by two different stimuli and independently stained to provide a visual display of neurons that are responsive to each stimulus. Two powerful features of this new imaging technique—the possibility of staining separate populations of activated neurons and the ability to visualize them at the cellular level—should extend IEG applications in biological activity mapping. 相似文献
6.
7.
Steuart K. Shapira Kent L. Anderson Avi Orr-Urtregar Willaim J. Craigen James R. Lupski Lisa G. Shaffer 《American journal of medical genetics. Part A》1994,52(1):44-50
We report on 2 unrelated patients who had chromosome analysis performed because of psychomotor delay, Failure to thrive, and minor anomalies. Each patient had a novel proximal 14q deletion (q11.2 to q21.1 in patient 737 and q12 to q22 in patient 777). Polymorphic (C-A)n microsatellite markers distributed along the length of chromosome 14q were examined in both patients and their parents in order to determine which marker loci were deleted. The deletion in patient 737 was found to be paternal in origin, based on the analysis of 2 marker loci (D14S54 and D14S70), thus assigning these loci to the deleted interval q11.2 q21.1. Furthermore, 3 loci were not deleted (TCRD, D14S50, and D14S80), suggesting that they are within or proximal to 14q11.2. In the other family (patient 777), none of the markers were fully informative, but the deleted chromosome was determined to be paternally derived based on cytogenetic heteromorphisms. Despite having overlapping proximal 14q deletions, these 2 patients shared few phenotypic similarities except for failure to thrive, micrognathia, and hypoplasia of the corpus callosum. Therefore, a distinct proximal 14q deletion syndrome is not yet apparent. However, the molecular analyses facilitated the localization of several 14q DNA markers to the deletion regions in these 2 patients, while excluding other markers from each deletion. © 1994 Wiley-Liss, Inc. 相似文献
8.
Einat Rabinovitch Dror Harats Pnina Yaron Tamar Luvish Merav Lidar Ron Kedem Aviv Shaish Issahar Ben-Dov Avi Livneh 《Annals of allergy, asthma & immunology》2007,99(6):517-521
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma. 相似文献
9.
Large-scale protein annotation through gene ontology 总被引:1,自引:0,他引:1
Xie H Wasserman A Levine Z Novik A Grebinskiy V Shoshan A Mintz L 《Genome research》2002,12(5):785-794
10.
Bleich M Hug MJ Heitzmann D Warth R Greger R 《Pflügers Archiv : European journal of physiology》1999,439(1-2):49-51
Previously we have shown that stimulation of in vitro perfused rectal gland tubules (RGT) of the dog-fish Squalus acanthias by adenosine 3',5'-cyclic monophosphate (cAMP), (as a cocktail comprising 0.1 mmol/l dibutyryl-cAMP, 10 micromol/l forskolin and 0.1 mmol/l adenosine, hereafter termed STIM) leads to an increase in cytosolic Ca2+ ([Ca2+]i) and that this assists Cl- secretion by enhancing basolateral K+ conductance. In the present study we examined the mechanism of the cAMP-induced increase in [Ca2+]i. [Ca2+]i was measured using the fura-2 technique in isolated in vitro perfused RGT. As before, STIM enhanced [Ca2+]i. This elevation of [Ca2+]i was prevented completely when STIM was added in the presence of the Na+2Cl-K+ cotransport inhibitor furosemide (0.5 mmol/l). This suggests that the increase in [Ca2+]i induced by STIM is caused by a concomitant increase in cytosolic Na+ ([Na+]i) and not by the activation of second messenger cascades. Furosemide prevents this increase in [Na+]i and hence the elevation of [Ca2+]i. Moreover, the plateau phase of the [Ca2+]i transient produced by carbachol (CCH, 0.1 mmol/l) was augmented strongly when bath Na+ was reduced to 5 mmol/l. These data suggest that the level of [Ca2+]i is determined by Na(+)-dependent Ca2+ export, most likely via a Na+/Ca2+ exchanger. The increase in [Na+]i accompanying stimulation of Cl- secretion reduces the rate of Ca2+ export leading to an elevation of [Ca2+]i, as does a reduction in bath Na+ which augments the [Ca2+]i plateau produced by CCH. 相似文献